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Sample records for one-pot multicomponent coupling

  1. Titanium-catalyzed multicomponent couplings: efficient one-pot syntheses of nitrogen heterocycles.

    PubMed

    Odom, Aaron L; McDaniel, Tanner J

    2015-11-17

    Nitrogen-based heterocycles are important frameworks for pharmaceuticals, natural products, organic dyes for solar cells, and many other applications. Catalysis for the formation of heterocyclic scaffolds, like many C-C and C-N bond-forming reactions, has focused on the use of rare, late transition metals like palladium and gold. Our group is interested in the use of Earth-abundant catalysts based on titanium to generate heterocycles using multicomponent coupling strategies, often in one-pot reactions. To be of maximal utility, the catalysts need to be easily prepared from inexpensive reagents, and that has been one guiding principle in the research. For this purpose, a series of easily prepared pyrrole-based ligands has been developed. Titanium imido complexes are known to catalyze the hydroamination of alkynes, and this reaction has been used to advantage in the production of α,β-unsaturated imines from 1,3-enynes and pyrroles from 1,4-diynes. Likewise, catalyst design can be used to find complexes applicable to hydrohydrazination, coupling of a hydrazine and alkyne, which is a method for the production of hydrazones. Many of the hydrazones synthesized are converted to indoles through Fischer cyclization by addition of a Lewis acid. However, more complex products are available in a single catalytic cycle through coupling of isonitriles, primary amines, and alkynes to give tautomers of 1,3-diimines, iminoamination (IA). The products of IA are useful intermediates for the one-pot synthesis of pyrazoles, pyrimidines, isoxazoles, quinolines, and 2-amino-3-cyanopyridines. The regioselectivity of the reactions is elucidated in some detail for some of these heterocycles. The 2-amino-3-cyanopyridines are synthesized through isolable intermediates, 1,2-dihydro-2-iminopyridines, which undergo Dimroth rearrangement driven by aromatization of the pyridine ring; the proposed mechanism of the reaction is discussed. The IA-based heterocyclic syntheses can be accomplished

  2. One-Pot Multicomponent Coupling Methods for the Synthesis of Diastereo- and Enantioenriched (Z)-Trisubstituted Allylic Alcohols

    PubMed Central

    Kerrigan, Michael H.; Jeon, Sang-Jin; Chen, Young K.; Salvi, Luca; Carroll, Patrick J.; Walsh, Patrick J.

    2009-01-01

    (Z)-Trisubstituted allylic alcohols are widespread structural motifs in natural products and biologically active compounds but are difficult to directly prepare. Introduced herein is a general one-pot multicomponent coupling method for the synthesis of (Z)-α,α,β-trisubstituted allylic alcohols. (Z)-Trisubstituted vinylzinc reagents are formed in situ by initial hydroboration of 1-bromo-1-alkynes. Addition of dialkylzinc reagents induces a 1,2-metallate rearrangement that is followed by a boron-to-zinc transmetallation. The resulting vinylzinc reagents add to a variety of prochiral aldehydes to produce racemic (Z)-trisubstituted allylic alcohols. When enantioenriched aldehyde substrates are employed (Z)-trisubstituted allylic alcohols are isolated with high dr (>20:1 in many cases). For example, vinylation of enantioenriched benzyl protected α- and β-hydroxy propanal derivatives furnished the expected anti-Felkin addition products via chelation control. Surprisingly, silyl protected α-hydroxy aldehydes also afford anti-Felkin addition products. A protocol for the catalytic asymmetric addition of (Z)-trisubstituted vinylzinc reagents to prochiral aldehydes with a (−)-MIB-based catalyst has also been developed. Several additives were investigated as inhibitors of the Lewis acidic alkylzinc halide byproducts, which promote the background reaction to form the racemate. α-Ethyl and α-cyclohexyl (Z)-trisubstituted allylic alcohols can now be synthesized with excellent levels of enantioselectivity in the presence of diamine inhibitors. PMID:19476375

  3. Pd- and Cu-catalyzed one-pot multicomponent synthesis of hetero α,α'-dimers of heterocycles.

    PubMed

    Murata, Takahiko; Murai, Masahito; Ikeda, Yuji; Miki, Koji; Ohe, Kouichi

    2012-05-01

    A novel palladium- and copper-catalyzed one-pot multicomponent synthesis of hetero α,α'-dimers of heterocycles via Sonogashira coupling and double cyclization cascade involving imine formation has been developed. This reaction cascade proceeded under mild conditions, providing a powerful synthetic tool for the assembly of π-conjugated systems with a combination of palladium-catalyzed post-direct C-H bond arylations. PMID:22533860

  4. Imides: forgotten players in the Ugi reaction. One-pot multicomponent synthesis of quinazolinones.

    PubMed

    Mossetti, Riccardo; Pirali, Tracey; Saggiorato, Dèsirèe; Tron, Gian Cesare

    2011-06-28

    Up to now, the synthesis of quinazolinones has required lengthy synthetic procedures. Here, we describe an innovative one-pot multicomponent reaction leading to highly substituted quinazolinones. We believe that this novel transformation may open the door for the generation of new and pharmacologically active quinazolinones, but, most important of all, the resurrection of the imide-Ugi scaffold paves the way for the synthesis of novel molecular architectures. PMID:21589958

  5. Chemoselective Multicomponent One-Pot Assembly of Purine Precursors in Water

    PubMed Central

    2010-01-01

    The recent development of a sequential, high-yielding route to activated pyrimidine nucleotides, under conditions thought to be prebiotic, is an encouraging step toward the greater goal of a plausible prebiotic pathway to RNA and the potential for an RNA world. However, this synthesis has led to a disparity in the methodology available for stepwise construction of the canonical pyrimidine and purine nucleotides. To address this problem, and further explore prebiotically accessible chemical systems, we have developed a high-yielding, aqueous, one-pot, multicomponent reaction that tethers masked-sugar moieties to prebiotically plausible purine precursors. A pH-dependent three-component reaction system has been discovered that utilizes key nucleotide synthons 2-aminooxazole and 5-aminoimidazoles, which allows the first divergent purine/pyrimidine synthesis to be proposed. Due to regiospecific aminoimidazole tethering, the pathway allows N9 purination only, thus suggesting the first prebiotically plausible mechanism for regiospecific N9 purination. PMID:21043502

  6. Multicomponent One-pot Reactions Towards the Synthesis of Stereoisomers of Dipicolylamine Complexes.

    PubMed

    Raje, Sakthi; Gurusamy, Sureshbabu; Koner, Abhishek; Mehrotra, Sonam; Jennifer, Samson Jegan; Vasudev, Prema G; Butcher, Ray J; Angamuthu, Raja

    2016-01-01

    Reported are multi-component one-pot syntheses of chiral complexes [M(L(R) OR')Cl2 ] or [M(L(R) SR')Cl2 ] from the mixture of an N-substituted ethylenediamine, pyridine-2-carboxaldehyde, a primary alcohol or thiol and MCl2 utilizing in-situ formed cyclized Schiff bases where a C-O bond, two stereocenters, and three C-N bonds are formed (M=Zn, Cu, Ni, Cd; R=Et, Ph; R'=Me, Et, nPr, nBu). Tridentate ligands L(R) OR' and L(R) SR' comprise two chiral centers and a hemiaminal ether or hemiaminal thioether moiety on the dipicolylamine skeleton. Syn-[Zn(L(Ph) OMe)Cl2 ] precipitates out readily from the reaction mixture as a major product whereas anti-[Zn(L(Ph) OMe)Cl2 ] stays in solution as minor product. Both syn-[Zn(L(Ph) OMe)Cl2 ] and anti-[Zn(L(Ph) OMe)Cl2 ] were characterized using NMR spectroscopy and mass spectrometry. Solid-state structures revealed that syn-[Zn(L(Ph) OMe)Cl2 ] adopted a square pyramidal geometry while anti-[Zn(L(Ph) OMe)Cl2 ] possesses a trigonal bipyramidal geometry around the Zn centers. The scope of this method was shown to be wide by varying the components of the dynamic coordination assembly, and the structures of the complexes isolated were confirmed by NMR spectroscopy, mass spectrometry, and X-ray crystallography. Syn complexes were isolated as major products with Zn(II) and Cu(II) , and anti complexes were found to be major products with Ni(II) and Cd(II) . Hemiaminals and hemiaminal ethers are known to be unstable and are seldom observed as part of cyclic organic compounds or as coordinated ligands assembled around metals. It is now shown, with the support of experimental results, that linear hemiaminal ethers or thioethers can be assembled without the assistance of Lewis acidic metals in the multi-component assembly, and a possible pathway of the formation of hemiaminal ethers has been proposed. PMID:26415522

  7. One-Pot Synthesis of Arylketones from Aromatic Acids via Palladium-Catalyzed Suzuki Coupling.

    PubMed

    Wu, Hongxiang; Xu, Baiping; Li, Yue; Hong, Fengying; Zhu, Dezhao; Jian, Junsheng; Pu, Xiaoer; Zeng, Zhuo

    2016-04-01

    A palladium-catalyzed one-pot procedure for the synthesis of aryl ketones has been developed. Triazine esters when coupled with aryl boronic acids provided aryl ketones in moderate to excellent yields (up to 95%) in the presence of 1 mol % Pd(PPh3)2Cl2 for 30 min. PMID:26949103

  8. Fabrication of aggregation induced emission active luminescent chitosan nanoparticles via a "one-pot" multicomponent reaction.

    PubMed

    Wan, Qing; Liu, Meiying; Xu, Dazhuang; Mao, Liucheng; Tian, Jianwen; Huang, Hongye; Gao, Peng; Deng, Fengjie; Zhang, Xiaoyong; Wei, Yen

    2016-11-01

    Chitosan based nanomaterials have been extensively examined for biomedical applications for their biodegradability, low toxicity, biological activity and low cost. In this work, a novel strategy for fabrication of luminescent polymeric nanoparticles (LPNs) based on aggregation induced emission (AIE) dye and water soluble chitosan (WS-Chitosan) were firstly developed via a highly efficient mercaptoacetic acid (MA) locking imine reaction. In this multicomponent reaction (MCR), MA serves as "lock" to connect 9,10-Bis(aldehydephenl)anthracene dye (An-CHO) and amino-containing WS-Chitosan under mild reaction conditions. The obtained WS-Chitosan@An-CHO LPNs show strong yellow emission and great water dispersibility. Biological evaluation results demonstrated that synthetic luminescent polymeric nanoparticles possess desirable cytocompatibility and distinct imaging properties. Therefore, we have developed a facile and useful method to fabricate AIE active nanoprobes with desirable properties for various biomedical applications. This strategy should be a general and easy handling tool to fabricate many other AIE dye based materials. PMID:27516264

  9. Synthesis of unnatural amino acids via microwave-assisted regio-selective one-pot multi-component reactions of sulfamidates

    EPA Science Inventory

    Synthesis of triazole-based unnatural amino acids, triazole bisaminoacids and β-amino triazole has been described via stereo and regioselective one-pot multi-component reaction of sulfamidates, sodium azide, and alkynes under MW irradiation conditions. The developed method is app...

  10. Chemodivergent, One-Pot, Multi-Component Synthesis of Pyrroles and Tetrahydropyridines under Solvent- and Catalyst-Free Conditions Using the Grinding Method.

    PubMed

    Dhinakaran, Isaivani; Padmini, Vediappen; Bhuvanesh, Nattamai

    2016-05-01

    A highly efficient, chemoselective synthesis of a library of polysubstituted pyrroles and tetrahydropyridines has been achieved through the one-pot, multicomponent reactions of ethyl (E)-3-(aryl/alkyl amino) acrylates, 2,2-dihydroxy-1-arylethan-1-ones, and malononitrile under solvent- and catalyst-free grinding conditions. The selective formation of pyrrole or tetrahydropyridines relied on substitution of the N-aryl of ethyl (E)-3-(4-arylamino) acrylates. These reactions presumably occurred via a domino Knoevenagel condensation and Michael addition followed by an intramolecular cyclization sequence of reactions in a single transformation. PMID:26972275

  11. Multicomponent versus domino reactions: One-pot free-radical synthesis of β-amino-ethers and β-amino-alcohols.

    PubMed

    Rossi, Bianca; Pastori, Nadia; Prosperini, Simona; Punta, Carlo

    2015-01-01

    Following an optimized multicomponent procedure, an aryl amine, a ketone, and a cyclic ether or an alcohol molecule are assembled in a one-pot synthesis by nucleophilic radical addition of ketyl radicals to ketimines generated in situ. The reaction occurs under mild conditions by mediation of the TiCl4/Zn/t-BuOOH system, leading to the formation of quaternary β-amino-ethers and -alcohols. The new reaction conditions guarantee good selectivity by preventing the formation of secondary products. The secondary products are possibly derived from a competitive domino reaction, which involves further oxidation of the ketyl radicals. PMID:25670994

  12. One-pot synthesis of a rose-like Pd-Fe3O4 nanocatalyst for Sonogashira coupling reactions

    NASA Astrophysics Data System (ADS)

    Woo, Hyunje; Lee, Kyoungho; Park, Ji Chan; Park, Kang Hyun

    2016-03-01

    A one-pot synthesis of rose-like Pd-Fe3O4 nanocomposites via the controlled thermal decomposition of Fe(CO)5 and reduction of Pd(OAc)2 is reported. This rose-like Pd-Fe3O4 composite structure has a high surface area owing to the individual Pd-Fe3O4 nanosheets, which imparted a high catalytic activity for Sonogashira coupling reactions. Moreover, the catalyst also demonstrated magnetic recyclability.

  13. Sequential decarboxylative azide–alkyne cycloaddition and dehydrogenative coupling reactions: one-pot synthesis of polycyclic fused triazoles

    PubMed Central

    Bharathimohan, Kuppusamy; Ponpandian, Thanasekaran; Bhuvanesh, Nattamai

    2014-01-01

    Summary Herein, we describe a one-pot protocol for the synthesis of a novel series of polycyclic triazole derivatives. Transition metal-catalyzed decarboxylative CuAAC and dehydrogenative cross coupling reactions are combined in a single flask and achieved good yields of the respective triazoles (up to 97% yield). This methodology is more convenient to produce the complex polycyclic molecules in a simple way. PMID:25670973

  14. Sequential decarboxylative azide-alkyne cycloaddition and dehydrogenative coupling reactions: one-pot synthesis of polycyclic fused triazoles.

    PubMed

    Bharathimohan, Kuppusamy; Ponpandian, Thanasekaran; Ahamed, A Jafar; Bhuvanesh, Nattamai

    2014-01-01

    Herein, we describe a one-pot protocol for the synthesis of a novel series of polycyclic triazole derivatives. Transition metal-catalyzed decarboxylative CuAAC and dehydrogenative cross coupling reactions are combined in a single flask and achieved good yields of the respective triazoles (up to 97% yield). This methodology is more convenient to produce the complex polycyclic molecules in a simple way. PMID:25670973

  15. Efficient one-pot protocol for diverse pyrazolylphosphonates by multi-component reactions: their antioxidant and antibacterial activities.

    PubMed

    Kang, So Rang; Lee, Yong Rok

    2015-05-01

    Efficient one-pot three-component reactions of pyrazolones with arylaldehydes and triethyl phosphite were carried out in the presence of ethylenediammonium diacetate as catalyst to synthesize biologically interesting pyrazolylphosphonate derivatives. This methodology offers several significant advantages such as environmentally benign character, the use of a mild catalyst, high yields, and ease of handling. The synthesized compounds were screened for their antioxidant and antibacterial activities. The result showed that compound 4d [Formula: see text] exhibited a strong free radical scavenger toward DPPH free radicals compared with standard BHT [Formula: see text]. In addition, compounds 4e and 4p showed potent antibacterial activities against Gram-negative bacteria of E. coli and compound 4o exhibited a potent activity against Gram-positive bacteria of S. aureus compared with standard Ampicillin. PMID:25652237

  16. Nano-ZnO catalyzed multicomponent one-pot synthesis of novel spiro(indoline-pyranodioxine) derivatives.

    PubMed

    Sachdeva, Harshita; Saroj, Rekha; Dwivedi, Diksha

    2014-01-01

    A simple catalytic protocol for the synthesis of novel spiro[indoline-pyranodioxine] derivatives has been developed using ZnO nanoparticle as an efficient, green, and reusable catalyst. The derivatives are obtained in moderate to excellent yield by one-pot three-component reaction of an isatin, malononitrile/ethylcyanoacetate, and 2,2-dimethyl-1,3-dioxane-4,6-dione in absolute ethanol under conventional heating and microwave irradiation. The catalyst was recovered by filtration from the reaction mixture and reused during five consecutive runs without any apparent loss of activity for the same reaction. The mild reaction conditions and recyclability of the catalyst make it environmentally benign synthetic procedure. PMID:24683341

  17. Nano-ZnO Catalyzed Multicomponent One-Pot Synthesis of Novel Spiro(indoline-pyranodioxine) Derivatives

    PubMed Central

    Sachdeva, Harshita; Saroj, Rekha; Dwivedi, Diksha

    2014-01-01

    A simple catalytic protocol for the synthesis of novel spiro[indoline-pyranodioxine] derivatives has been developed using ZnO nanoparticle as an efficient, green, and reusable catalyst. The derivatives are obtained in moderate to excellent yield by one-pot three-component reaction of an isatin, malononitrile/ethylcyanoacetate, and 2,2-dimethyl-1,3-dioxane-4,6-dione in absolute ethanol under conventional heating and microwave irradiation. The catalyst was recovered by filtration from the reaction mixture and reused during five consecutive runs without any apparent loss of activity for the same reaction. The mild reaction conditions and recyclability of the catalyst make it environmentally benign synthetic procedure. PMID:24683341

  18. Anomalous regioselective four-member multicomponent Biginelli reaction II: one-pot parallel synthesis of spiro heterobicyclic aliphatic rings.

    PubMed

    Byk, Gerardo; Kabha, Eihab

    2004-01-01

    In a previous preliminary study, we found that a cyclic five-member ring beta-keto ester (lactone) reacts with one molecule of urea and two of aldehyde to give a new family of spiro heterobicyclic aliphatic rings in good yields with no traces of the expected dihydropyrimidine (Biginelli) products. The reaction is driven by a regiospecific condensation of two molecules of aldehyde with urea and beta-keto-gamma-lactone to afford only products harboring substitutions exclusively in a syn configuration (Byk, G.; Gottlieb, H. E.; Herscovici, J.; Mirkin, F. J. Comb. Chem. 2000, 2, 732-735). In the present work ((a) Presented in part at ISCT Combitech, October 15, 2002, Israel, and Eurocombi-2, Copenhagen 2003 (oral and poster presentation). (b) Also in American Peptide Society Symposium, Boston, 2003 (poster presentation). (c) Abstract in Biopolymers 2003, 71 (3), 354-355), we report a large and exciting extension of this new reaction utilizing parallel organic synthesis arrays, as demonstrated by the use of chiral beta-keto-gamma-lactams, derived from natural amino acids, instead of tetronic acid (beta-keto-gamma-lactone) and the potential of the spirobicyclic products for generating "libraries from libraries". Interestingly, we note an unusual and important anisotropy effect induced by perpendicular interactions between rigid pi systems and different groups placed at the alpha position of the obtained spirobicyclic system. Stereo/regioselectivity of the aldehyde condensation is driven by the nature of the substitutions on the starting beta-keto-gamma-lactam. Aromatic aldehydes can be used as starting reagents with good yields; however, when aliphatic aldehydes are used, the desired products are obtained in poor yields, as observed in the classical Biginelli reaction. The possible reasons for these poor yields are addressed and clarify, to some extent, the complexity of the Biginelli multicomponent reaction mechanism and, in particular, the mechanism of the present

  19. Preparation of peptide-functionalized gold nanoparticles using one pot EDC/sulfo-NHS coupling.

    PubMed

    Bartczak, Dorota; Kanaras, Antonios G

    2011-08-16

    Although carbodiimides and succinimides are broadly employed for the formation of amide bonds (i.e., in amino acid coupling), their use in the coupling of peptides to water-soluble carboxylic-terminated colloidal gold nanoparticles remains challenging. In this article, we present an optimization study for the successful coupling of the KPQPRPLS peptide to spherical and rodlike colloidal gold nanoparticles. We show that the concentration, reaction time, and chemical environment are all critical to achieving the formation of robust, peptide-coated colloidal nanoparticles. Agarose gel electrophoresis was used for the characterization of conjugates. PMID:21728291

  20. A versatile approach to flavones via a one-pot Pd(II)-catalyzed dehydrogenation/oxidative boron-Heck coupling sequence of chromanones.

    PubMed

    Lee, Jun; Yu, Jihyun; Son, Seung Hwan; Heo, Jinyuk; Kim, Taelim; An, Ji-Young; Inn, Kyung-Soo; Kim, Nam-Jung

    2016-01-14

    A variety of flavones were expediently synthesized from readily accessible chromanones via a one-pot sequence involving Pd(II)-catalyzed dehydrogenation and oxidative boron-Heck coupling with arylboronic acid pinacol esters. In particular, the use of arylboronic acid pinacol esters was found to significantly improve the yield of the reaction. PMID:26592753

  1. Copper-catalyzed one-pot denitrogenative-dehydrogenative-decarboxylative coupling of β-ketoacids with trifluorodiazoethane: facile access to trifluoromethylated aldol products.

    PubMed

    Xiong, Heng-Ying; Yang, Zhen-Yan; Chen, Zhen; Zeng, Jun-Liang; Nie, Jing; Ma, Jun-An

    2014-07-01

    A novel copper-catalyzed one-pot cross-coupling of β-ketoacids with in situ generated trifluorodiazoethane has been developed. This reaction provides a direct and efficient method, in which one C-C bond and one C-O bond were formed in a carbenoid center with concomitant denitrogenation-dehydrogenation-decarboxylation, to afford trifluoromethylated aldol products. In several preliminary experiments, good to high enantioselectivities were also obtained. PMID:24889186

  2. Synthesis of 2-aminoquinoline-3-carboamides and pyrimido[4,5-b]quinolin-4-ones through copper-catalyzed one-pot multicomponent reactions.

    PubMed

    Zhang, Xin-Ying; Guo, Xiao-Jie; Fan, Xue-Sen

    2015-01-01

    Pyrimido[4,5-b]quinolinones have attracted considerable interest from both chemical and medicinal scientists as these compounds display remarkable antimicrobial, anti-inflammatory, antitumor, antiallergy, analgesic, and antioxidant activities. The importance of pyrimido[4,5-b]quinolinones has stimulated enormous efforts to develop efficient methodologies for their synthesis. Herein, we disclose a novel synthetic protocol toward pyrimido[4,5-b]quinolin-4-ones through Cu(OAc)2 -catalyzed one-pot four-component reactions of 2-bromobenzaldehydes, aqueous ammonia, cyanoacetamides and aldehydes. The synthetic procedure combines amination/condensation/cyclization/dehydrogenation reactions in one pot, allowing synthesis of complex compounds in a simple and practical manner. Compared with literature procedures, the synthetic strategies developed herein showed advantages such as readily available and economically sustainable starting materials, structural diversity of products, good functional group tolerance, and a remarkably simple operation process. PMID:25318983

  3. One-pot synthesis of 1H-isochromenes and 1,2-dihydroisoquinolines by a sequential isocyanide-based multicomponent/Wittig reaction.

    PubMed

    Wang, Long; Guan, Zhi-Rong; Ding, Ming-Wu

    2016-02-28

    A one-pot synthesis of 1H-isochromenes and 1,2-dihydroisoquinolines by a I-MCR/Wittig sequence was developed. The reaction of phosphonium salt , an acid, an amine (or without), and an isocyanide gave the 1H-isochromenes or 1,2-dihydroisoquinolines in good yields by a sequential Passerini or Ugi condensation and an intramolecular Wittig reaction in the presence of K2CO3. PMID:26810599

  4. One-pot synthesis of 4′-alkyl-4-cyanobiaryls on the basis of the terephthalonitrile dianion and neutral aromatic nitrile cross-coupling

    PubMed Central

    Peshkov, Roman Yu; Chunyan, Wang; Tretyakov, Evgeny V; Shteingarts, Vitalij D

    2016-01-01

    Summary A convenient one-pot approach to alkylcyanobiaryls is described. The method is based on biaryl cross-coupling between the sodium salt of the terephthalonitrile dianion and a neutral aromatic nitrile in liquid ammonia, and successive alkylation of the long-lived anionic intermediate with alkyl bromides. The reaction is compatible with benzonitriles that contain methyl, methoxy and phenyl groups, fluorine atoms, and a 1-cyanonaphthalene residue. The variety of ω-substituted alkyl bromides, including an extra bromine atom, a double bond, cyano and ester groups, as well as a 1,3-dioxane fragment are suitable as alkylation reagents. PMID:27559409

  5. One-pot synthesis of 4'-alkyl-4-cyanobiaryls on the basis of the terephthalonitrile dianion and neutral aromatic nitrile cross-coupling.

    PubMed

    Peshkov, Roman Yu; Panteleeva, Elena V; Chunyan, Wang; Tretyakov, Evgeny V; Shteingarts, Vitalij D

    2016-01-01

    A convenient one-pot approach to alkylcyanobiaryls is described. The method is based on biaryl cross-coupling between the sodium salt of the terephthalonitrile dianion and a neutral aromatic nitrile in liquid ammonia, and successive alkylation of the long-lived anionic intermediate with alkyl bromides. The reaction is compatible with benzonitriles that contain methyl, methoxy and phenyl groups, fluorine atoms, and a 1-cyanonaphthalene residue. The variety of ω-substituted alkyl bromides, including an extra bromine atom, a double bond, cyano and ester groups, as well as a 1,3-dioxane fragment are suitable as alkylation reagents. PMID:27559409

  6. Cu-Catalyzed Multicomponent Reaction of Styrenes, Perfluoroalkyl Halide, Alcohol, and tert-Butyl Hydroperoxide: One-Pot Synthesis of (Z)-β-Alkoxyperfluoroalkenone.

    PubMed

    Luo, Qiang; Liu, Chunmei; Tong, Jingjing; Shao, Ying; Shan, Wenyu; Wang, Hanghang; Zheng, Hao; Cheng, Jiang; Wan, Xiaobing

    2016-04-15

    An efficient synthesis of Z-perfluoroalkyl-substituted enones by a multicomponent reaction strategy has been described. A variety of elusive perfluoroalkylated enones are furnished under mild reaction conditions in good yields with unique chemo- and stereoselectivity. A sequence of radical-mediated Kornblum-DeLaMare reaction, Michael addition, and HF elimination is proposed for the mechanism. PMID:26980724

  7. A Research-Based Undergraduate Organic Laboratory Project: Investigation of a One-Pot, Multicomponent, Environmentally Friendly Prins-Friedel-Crafts-Type Reaction

    ERIC Educational Resources Information Center

    Dintzner, Matthew R.; Maresh, Justin J.; Kinzie, Charles R.; Arena, Anthony F.; Speltz, Thomas

    2012-01-01

    Students in the undergraduate organic laboratory synthesize tetrahydro-2-(4-nitrophenyl)-4-phenyl-2"H"-pyran via the Montmorillonite K10 clay-catalyzed reaction of p-nitrobenzaldehye with methanol, 3-buten-1-ol, and benzene. The synthesis comprises an environmentally friendly tandem Prins-Friedel-Crafts-type multicomponent reaction (MCR) and sets…

  8. One-pot multi-component synthesis of 1,4-dihydropyridines using Zn(2+) @KSF and evaluating their antibacterial and antioxidant activities.

    PubMed

    Mahmoodi, Nosrat O; Ramzanpour, Sahar; Ghanbari Pirbasti, Fateme

    2015-04-01

    New 5-aryl-10-(4-(4-methoxyphenyl)thiazole-2-yl)-9,10-dihydropyrido[2,3-d:5,6-d']dipyrimidinone-2,4,6,8-(1H,3H,5H,7H)-tetraones 6a-d were synthesized through one-pot four-component reaction of aldehydes, barbituric acid, and thiazole using Zn(2+) @KSF under reflux condition. The key features of this reaction are: incorporating four heterocyclic rings, using a heterogeneous and efficient catalyst, high yield, and easy-to-setup reaction. The structure of the products was confirmed by FT-IR, (1)H NMR, and (13)C NMR spectra. The antibacterial activities of compounds 6a-d were screened against Escherichia coli, Micrococcus luteus, Pseudomonas aeruginosa, and Staphylococcus aureus bacterial strains using the zone inhibition method. Also, the 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of compounds 6a-d were evaluated. All compounds showed good antioxidant capacity in comparison to ascorbic acid. The IC50 values of the antioxidant activity were calculated. The proposed mechanism for antioxidant activity is discussed. PMID:25708128

  9. Nickel-Catalyzed Reductive Cross-Coupling of Benzyl Chlorides with Aryl Chlorides/Fluorides: A One-Pot Synthesis of Diarylmethanes.

    PubMed

    Zhang, Jie; Lu, Gusheng; Xu, Jin; Sun, Hongmei; Shen, Qi

    2016-06-17

    The first nickel-catalyzed, magnesium-mediated reductive cross-coupling between benzyl chlorides and aryl chlorides or fluorides is reported. A variety of diarylmethanes can be prepared in good to excellent yields in a one-pot manner using easy-to-access mixed PPh3/NHC Ni(II) complexes of Ni(PPh3)(NHC)Br2 (NHC = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, IPr, 1a; 1,3-di-tert-butylimidazol-2-ylidene, ItBu, 1b) as catalyst precursors. Activation of polychloroarenes or chemoselective cross-coupling based on the difference in catalytic activity between 1a and 1b is used to construct oligo-diarylmethane motifs. PMID:27268781

  10. Two-step one-pot synthesis of benzoannulated spiroacetals by Suzuki-Miyaura coupling/acid-catalyzed spiroacetalization.

    PubMed

    Butkevich, Alexey N; Corbu, Andrei; Meerpoel, Lieven; Stansfield, Ian; Angibaud, Patrick; Bonnet, Pascal; Cossy, Janine

    2012-10-01

    Substituted benzoannulated spiroacetals were prepared from (2-haloaryl)alkyl alcohols and dihydropyranyl or dihydrofuranyl pinacol boronates using a Suzuki-Miyaura coupling followed by an acid-catalyzed spirocyclization. Application of the reaction to a glycal boronate provides an approach to annulated spiroacetals in enantiopure form. PMID:22998767

  11. Reductive coupling of phthalimides with ketones and aldehydes by low-valent titanium: one-pot synthesis of alkylideneisoindolin-1-ones.

    PubMed

    Kise, Naoki; Kawano, Yusuke; Sakurai, Toshihiko

    2013-12-20

    The reductive coupling of phthalimides with ketones and aldehydes by Zn-TiCl4 in THF gave two- and four-electron reduced products, 3-hydroxy-3-(1-hydroxyalkyl)isoindolin-1-ones and alkylideneisoindolin-1-ones, selectively by controlling the reaction conditions. Therefore, the one-pot synthesis of alkylideneisoindolin-1-ones from phthalimides was effected by this reaction. Although the alkylideneisoindolin-1-ones prepared from phthalimides and aldehydes were formed as mixtures of geometric isomers in most cases, the geometric ratios could be increased by reflux in cat. PPTS/toluene. After the isomerization, the E-isomers of N-methyl substituted alkylideneisoindolin-1-ones (X = Me, R(1) = R, R(2) = H) and the Z-isomers of N-unsubstituted alkylideneisoindolin-1-ones (X = H, R(1) = H, R(2) = R) were obtained preferentially. PMID:24266907

  12. Efficient one-pot enzymatic synthesis of alpha-(1-->4)-glucosidic disaccharides through a coupled reaction catalysed by Lactobacillus acidophilus NCFM maltose phosphorylase.

    PubMed

    Nakai, Hiroyuki; Dilokpimol, Adiphol; Abou Hachem, Maher; Svensson, Birte

    2010-05-27

    Lactobacillus acidophilus NCFM maltose phosphorylase (LaMalP) of glycoside hydrolase family 65 catalysed enzymatic synthesis of alpha-(1-->4)-glucosidic disaccharides from maltose and five monosaccharides in a coupled phosphorolysis/reverse phosphorolysis one-pot reaction. Thus phosphorolysis of maltose to beta-glucose 1-phosphate circumvented addition of costly beta-glucose 1-phosphate for reverse phosphorolysis with different monosaccharide acceptors, resulting in 91%, 89%, 88%, 86% and 84% yield of alpha-d-glucopyranosyl-(1-->4)-N-acetyl-D-glucosaminopyranose [N-acetyl-maltosamine], alpha-D-glucopyranosyl-(1-->4)-D-glucosaminopyranose [maltosamine], alpha-D-glucopyranosyl-(1-->4)-D-mannopyranose, alpha-D-glucopyranosyl-(1-->4)-L-fucopyranose and alpha-D-glucopyranosyl-(1-->4)-D-xylopyranose, respectively, from 0.1M maltose, 0.5M N-acetyl glucosamine, 0.1M glucosamine, 0.1M mannose, 1M L-fucose and 0.5M xylose in 0.2M phosphate-citrate pH 6.2. These current yields of 0.27-0.34 g of disaccharide products from 10 mL reaction mixtures are easy to scale up and moreover the strategy can be applied to large-scale production of other oligosaccharides from low-cost disaccharides as catalysed by phosphorylases with different substrate specificities. PMID:20392438

  13. Chelation-assisted Pd-catalysed ortho-selective oxidative C-H/C-H cross-coupling of aromatic carboxylic acids with arenes and intramolecular Friedel-Crafts acylation: one-pot formation of fluorenones.

    PubMed

    Sun, Denan; Li, Bijin; Lan, Jingbo; Huang, Quan; You, Jingsong

    2016-03-01

    Pd-Catalysed ortho-selective oxidative C-H/C-H cross-coupling of aromatic carboxylic acids with arenes and subsequent intramolecular Friedel-Crafts acylation has been accomplished for the first time through a chelation-assisted C-H activation strategy. Starting from the readily available substrates, a variety of fluorenone derivatives are obtained in one pot. The direct use of naturally occurring carboxylic acid functionalities as directing groups avoids unnecessary steps for installation and removal of an extra directing group. PMID:26861768

  14. One-pot synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines using supported gold and base as catalysts.

    PubMed

    Kegnæs, Søren; Mielby, Jerrik; Mentzel, Uffe V; Jensen, Thomas; Fristrup, Peter; Riisager, Anders

    2012-02-28

    Synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines via intermediate formation of methyl esters is highly efficient and selective when using a catalytic system comprised of supported gold nanoparticles and added base in methanol. PMID:22274843

  15. One-Pot Syntheses of Immunostimulatory Glycolipids

    PubMed Central

    Schombs, Matthew; Park, Francine E.; Du, Wenjun; Kulkarni, Suvarn S.; Gervay-Hague, Jacquelyn

    2010-01-01

    Glycolipids containing α-linked galactosyl and glucosyl moieties have been shown to possess unique immunostimulatory activity creating a need for access to diverse and anomerically pure sources of these compounds for immunological studies. To meet this demand, glycosyl iodides were enlisted in the synthesis of these biologically relevant glycoconjugates. In the first generation protocol per-O-benzyl galactosyl iodide was efficiently coupled with activated sphingosine acceptors, but fully functionalized ceramides were found to be unreactive. To overcome this obstacle, per-O-trimethylsilyl glycosyl iodides were investigated and shown to undergo highly efficient coupling with ceramide and glycerol ester acceptors. Contrary to what has been observed with other donors, we detected little difference between the reactivity of glucosyl and galactosyl iodides. The trimethylsilyl protecting groups play a dual role in activating the donor toward nucleophilic attack while at the same time providing transient protection: the silyl groups are readily removed upon methanolysis. All reactions proceeded with complete acceptor regioselectivity, eliminating the need for additional protecting group manipulations, and the desired α -anomers were formed exclusively. This three step one-pot synthetic platform provides rapid access to an important class of immunostimulatory molecules including the first reported synthesis of the glucosyl analog of the bacterial antigen BbGL-II. PMID:20387787

  16. Novel One-pot Fabrication of Lab-on-a-Bubble@Ag Substrate without Coupling-agent for Surface Enhanced Raman Scattering

    PubMed Central

    Jiang, Jizhou; Ou-Yang, Lei; Zhu, Lihua; Zou, Jing; Tang, Heqing

    2014-01-01

    Through in-situ reduction of silver nitrate without using any coupling-agent, a substrate for surface-enhanced Raman scattering (SERS) was prepared by coating silver on hollow buoyant silica microspheres as a lab on a bubble (LoB). The silver coated LoBs (LoBs@Ag) floated on surface of a solution could provide a very convenient platform for the detection of target molecules in the solution. The LoBs@Ag substrate not only immobilized well-distributed Ag nanoparticles on the surface LoBs, but excluded the interference of coupling agents. This yielded high-resolution SERS spectra with excellent reproducibility. The adsorption of crystal violet (CV) on the LoBs@Ag substrate was investigated by means of SERS combined with density functional theory (DFT) calculations. The LoBs@Ag substrate exhibited a remarkable Raman enhancement effect for CV with an enhancement factor of 6.9 × 108 and wide adaptability from dye, pesticide to bio-molecules. On the basis of this substrate, a simple and sensitive SERS method was proposed for the determination of trace organic pollutants or bio-molecules. PMID:24487575

  17. One-Pot Synthesis of Urchin-like FePd-Fe3O4 and Their Conversion into Exchange-Coupled L10-FePd-Fe Nanocomposite Magnets

    SciTech Connect

    Yu, Yongsheng; Sun, Kewei; Tian, Yuan; Li, X.-Z.; Kramer, Matthew J.; Sellymyer, D. J.; Shield, J. E.; Sun, Shouheng

    2013-09-16

    We report a one-pot synthesis of urchin-like FePd-Fe3O4 nanocomposites, spherical clusters of FePd nanoparticles (NPs) with spikes of Fe3O4 nanorods (NRs), via controlled thermal decomposition of Fe(CO)5 and reduction of Pd(acac)2. The FePd NPs with sizes between 6 and 9 nm self-aggregate into 60 nm superparticles (SPs), and Fe3O4 NRs grow on the surface of these SPs. Reductive annealing at 500 °C converts the FePd-Fe3O4 into exchange-coupled nanocomposites L1(0)-FePd-Fe with their Hc tunable from 0.8 to 2.6 kOe and Ms controlled from 90 to 190 emu/g. The work provides a general approach to L1(0)-FePd-Fe nanocomposite magnets for understanding exchange coupling at the nanoscale. The concept may be extended to other magnetic nanocomposite systems and may help to build superstrong magnets for magnetic applications.

  18. One-pot synthesis of (-)-Ambrox.

    PubMed

    Yang, Shaoxiang; Tian, Hongyu; Sun, Baoguo; Liu, Yongguo; Hao, Yanfeng; Lv, Yanyu

    2016-01-01

    (-)-Ambrox is recognised as the prototype of all ambergris odorants. Widely used in perfumery, (-)-Ambrox is an important ingredient due to its unique scent and excellent fixative function. An environmentally friendly and practical preparation of (-)-Ambrox is still unavailable at present although a lot of attention has been paid to this hot research topic for many years. A one-pot synthesis of (-)-Ambrox was studied starting from (-)-sclareol through oxidation with hydrogen peroxide in the presence of a quaternary ammonium phosphomolybdate catalyst {[C5H5NC16H33] [H2PMo12O40]}, which gave the product a 20% overall yield. PMID:27581945

  19. Stereo- and regio-selective one-pot synthesis of triazole-based unnatural amino acids and β- amino triazoles

    EPA Science Inventory

    Synthesis of triazole based unnatural amino acids and β-amino triazole has been described via stereo and regioselective one-pot multi-component reaction of sulfamidates, sodium azide, and alkynes under MW conditions. The developed method is applicable to a broad substrate scope a...

  20. A rare γ-pyranopyrazole skeleton: design, one-pot synthesis and computational study.

    PubMed

    Üçüncü, Muhammed; Cantürk, Ceren; Karakuş, Erman; Zeybek, Hüseyin; Bozkaya, Uğur; Soydaş, Emine; Şahin, Ertan; Emrullahoğlu, Mustafa

    2016-08-21

    Drawing upon a consecutive amide coupling and intramolecular cyclisation pathway, a one-pot, straightforward synthetic route has been developed for a range of pyrazole fused γ-pyrone derivatives. The reaction mechanism proposed for the chemoselective formation of γ-pyranopyrazole is furthermore fully supported by experimental and computational studies. PMID:27405663

  1. Efficient one-pot synthesis of 1-arylcycloprop-2-ene-1-carboxamides.

    PubMed

    Edwards, Andrew; Rubin, Michael

    2016-03-14

    An expeditious and cost-efficient method for synthesis of 1-arylcycloprop-2-ene-1-carboxamides was developed. This one-pot protocol involving coupling of amines with acyl chlorides, generated upon treatment of cyclopenylcarboxylic acids with oxalyl chloride, is applicable for the preparation of sensitive products with a reactive, unsubstituted strained double bond. PMID:26864495

  2. A one-pot approach to pyridyl isothiocyanates from amines.

    PubMed

    Zhang, Hao; Liu, Rui-Quan; Liu, Ke-Chang; Li, Qi-Bo; Li, Qing-Yang; Liu, Shang-Zhong

    2014-01-01

    A one-pot preparation of pyridyl isothiocyanates (ITCs) from their corresponding amines has been developed. This method involves aqueous iron(III) chloride-mediated desulfurization of a dithiocarbamate salt that is generated in situ by treatment of an amine with carbon disulfide in the present of DABCO or sodium hydride. The choice of base is of decisive importance for the formation of the dithiocarbamate salts. This one-pot process works well for a wide range of pyridyl ITCs. Utilizing this protocol, some highly electron-deficient pyridyl and aryl ITCs are obtained in moderate to good yields. PMID:25185069

  3. Visible-light-induced, copper(I)-catalysed C-N coupling between o-phenylenediamine and terminal alkynes: one-pot synthesis of 3-phenyl-2-hydroxy-quinoxalines.

    PubMed

    Sagadevan, Arunachalam; Ragupathi, Ayyakkannu; Hwang, Kuo Chu

    2013-12-01

    Visible-light-initiated aerobic direct C-N coupling between o-phenylenediamines and terminal acetylenes was performed using simple copper(I) chloride as a catalyst for the synthesis of quinoxaline derivatives. The current method works well for a wide range of electron rich as well as electron poor group-substituted o-phenylenediamines and phenylacetylenes. The key component in the reaction is the direct photo-excitation of in situ generated copper arylacetylide (λ(abs) = 420-480 nm). Moreover, as compared to the literature reports (thermal process), the current photochemical method is simple, mild, high yielding, and more viable towards the construction of biologically important quinoxaline derivatives from easily accessible raw materials, without the need of ligands and strong oxidants. PMID:24057350

  4. One-pot, three-component arylalkynyl sulfone synthesis.

    PubMed

    Chen, C Chun; Waser, Jerome

    2015-02-01

    A one-pot three-component protocol for the preparation of arylsulfonyl alkynes through the reaction of ethynyl-benziodoxolone (EBX) reagents, DABSO (DABCO·SO2), and either organomagnesium reagents or aryl iodides with a palladium catalyst is reported. A broad range of aryl and heteroarylalkynyl sulfones were obtained in 46-85% overall yield. PMID:25633719

  5. Catalytic bismetallative multicomponent coupling reactions: scope, applications, and mechanisms

    PubMed Central

    Cho, Hee Yeon

    2014-01-01

    Catalytic reactions have played an indispensable role in organic chemistry for the last several decades. In particular, catalytic multicomponent reactions have attracted a lot of attention due to their efficiency and expediency towards complex molecule synthesis. The presence of bismetallic reagents (e.g. B–B, Si–Si, B–Si, Si–Sn, etc.) in this process renders the products enriched with various functional groups and multiple stereocenters. For this reason, catalytic bismetallative coupling is considered an effective method to generate the functional and stereochemical complexity of simple hydrocarbon substrates. This review highlights key developments of transition-metal catalyzed bismetallative reactions involving multiple π components. Specifically, it will highlight the scope, synthetic applications, and proposed mechanistic pathways of this process. PMID:24736839

  6. Photoorganocatalytic One-Pot Synthesis of Hydroxamic Acids from Aldehydes.

    PubMed

    Papadopoulos, Giorgos N; Kokotos, Christoforos G

    2016-05-10

    An efficient one-pot synthesis of hydroxamic acids from aldehydes and hydroxylamine is described. A fast, visible-light-mediated metal-free hydroacylation of dialkyl azodicarboxylates was used to develop the subsequent addition of hydroxylamine hydrochloride. A range of aliphatic and aromatic aldehydes were employed in this reaction to give hydroxamic acids in high to excellent yields. Application of the current methodology was demonstrated in the synthesis of the anticancer medicine vorinostat. PMID:27038037

  7. Diastereoselective one-pot Knoevenagel condensation/Corey-Chaykovsky cyclopropanation.

    PubMed

    Clemens, Jeremy J; Asgian, Juliana L; Busch, Brett B; Coon, Timothy; Ernst, Justin; Kaljevic, Leonard; Krenitsky, Paul J; Neubert, Timothy D; Schweiger, Edwin J; Termin, Andreas; Stamos, Dean

    2013-01-18

    Efforts to substitute the cyclopropane ring in a series of aryl cyclopropylnitriles led to the discovery of an operationally simple one-pot method for Knoevenagel condensation and subsequent Corey-Chaykovsky cyclopropanation giving diastereomerically pure products as a racemic mixture of enantiomers. Method development and results for variably substituted aryl acetonitriles and aldehydes in the reaction are reported. A concise synthesis of (±)-bicifadine in two steps is provided to demonstrate the utility of the method. PMID:23252964

  8. (2+1)-dimensional non-isospectral multi-component AKNS equations and its integrable couplings

    SciTech Connect

    Sun Yepeng

    2010-03-08

    (2+1)-dimensional non-isospectral multi-component AKNS equations are derived from an arbitrary order matrix spectral problem. As a reduction, (2+1)-dimensional non-isospectral multi-component Schroedinger equations are obtained. Moreover, new (2+1)-dimensional non-isospectral integrable couplings of the resulting AKNS equations are constructed by enlarging the associated matrix spectral problem.

  9. A palladium-catalysed multicomponent coupling approach to conjugated poly(1,3-dipoles) and polyheterocycles

    PubMed Central

    Leitch, David C.; Kayser, Laure V.; Han, Zhi-Yong; Siamaki, Ali R.; Keyzer, Evan N.; Gefen, Ashley; Arndtsen, Bruce A.

    2015-01-01

    Conjugated polymers have emerged over the past several decades as key components for a range of applications, including semiconductors, molecular wires, sensors, light switchable transistors and OLEDs. Nevertheless, the construction of many such polymers, especially highly substituted variants, typically involves a multistep synthesis. This can limit the ability to both access and tune polymer structures for desired properties. Here we show an alternative approach to synthesize conjugated materials: a metal-catalysed multicomponent polymerization. This reaction assembles multiple monomer units into a new polymer containing reactive 1,3-dipoles, which can be modified using cycloaddition reactions. In addition to the synthetic ease of this approach, its modularity allows easy adaptation to incorporate a range of desired substituents, all via one-pot reactions. PMID:26077769

  10. Cyclometalated Pd(II) and Ir(III) 2-(4-bromophenyl)pyridine complexes with N-heterocyclic carbenes (NHCs) and acetylacetonate (acac): synthesis, structures, luminescent properties and application in one-pot oxidation/Suzuki coupling of aryl chlorides containing hydroxymethyl.

    PubMed

    Xu, Chen; Li, Hong-Mei; Xiao, Zhi-Qiang; Wang, Zhi-Qiang; Tang, Si-Fu; Ji, Bao-Ming; Hao, Xin-Qi; Song, Mao-Ping

    2014-07-14

    A series of cyclopalladated 2-(4-bromophenyl)pyridine (bpp) complexes [Pd(bpp)(NHC)Cl] 1-3, [Pd(bpp)(acac)] 4, cyclometalated iridium(iii) complexes [Ir(bpp)2Cl]25 and [Ir(bpp)2(acac)] 6 have been synthesized and characterized. Their detailed structures have been determined by X-ray diffraction and many intermolecular C-HX (Cl, Br, π) and ππ interactions were found in their crystals. Cyclometalated complexes 1-4 and 6 exhibit luminescence with emission peaks of 390-543 nm in dichloromethane solution under UV irradiation. Their application to coupling reactions of aryl chlorides containing hydroxymethyl was also investigated. An efficient 3/Cu cocatalyzed oxidation/Suzuki reaction for the synthesis of biarylaldehydes from chloro-phenylmethanol and arylboronic acids in air has been developed. In addition, a 6/3-cocatalyzed one-pot reaction of acetylferrocene, (2-amino-5-chlorophenyl)methanol, and arylboronic acids provided 6-aryl-2-ferrocenylquinolines in moderate to good yields. PMID:24878778

  11. One-pot synthesis of vinca alkaloids-phomopsin hybrids.

    PubMed

    Gherbovet, Olga; Coderch, Claire; García Alvarez, María Concepción; Bignon, Jérôme; Thoret, Sylviane; Guéritte, Françoise; Gago, Federico; Roussi, Fanny

    2014-06-26

    Hybrids of vinca alkaloids and phomopsin A have been elaborated with the aim of interfering with the "vinca site" and the "peptide site" of the vinca domain in tubulin. They were synthesized by an efficient one-pot procedure that directly links the octahydrophomopsin lateral chain to the velbenamine moiety of 7'-homo-anhydrovinblastine. In their modeled complexes with tubulin, these hybrids were found to superimpose nicely on the tubulin-bound structures of vinblastine and phomopsin A. This good matching can account for the fact that two of them are very potent inhibitors of microtubules assembly and are cytotoxic against four cancer cell lines. PMID:24871162

  12. Synthesis of l- and d-Ubiquitin by One-Pot Ligation and Metal-Free Desulfurization.

    PubMed

    Huang, Yi-Chao; Chen, Chen-Chen; Gao, Shuai; Wang, Ye-Hai; Xiao, Hua; Wang, Feng; Tian, Chang-Lin; Li, Yi-Ming

    2016-05-23

    Native chemical ligation combined with desulfurization has become a powerful strategy for the chemical synthesis of proteins. Here we describe the use of a new thiol additive, methyl thioglycolate, to accomplish one-pot native chemical ligation and metal-free desulfurization for chemical protein synthesis. This one-pot strategy was used to prepare ubiquitin from two or three peptide segments. Circular dichroism spectroscopy and racemic protein X-ray crystallography confirmed the correct folding of ubiquitin. Our results demonstrate that proteins synthesized chemically by streamlined 9-fluorenylmethoxycarbonyl (Fmoc) solid-phase peptide synthesis coupled with a one-pot ligation-desulfurization strategy can supply useful molecules with sufficient purity for crystallographic studies. PMID:27075969

  13. Gold-catalyzed three-component spirocyclization: a one-pot approach to functionalized pyrazolidines.

    PubMed

    Wagner, Bernd; Hiller, Wolf; Ohno, Hiroaki; Krause, Norbert

    2016-02-01

    An efficient, highly atom economic synthesis of hitherto unknown spirocyclic pyrazolidines in a one-pot process was developed. The gold-catalyzed three-component coupling of alkynols, hydrazines and aldehydes or ketones likely proceeds via cycloisomerization of the alkynol to an exocyclic enol ether and subsequent [3 + 2]-cycloaddition of an azomethine ylide. A library of 29 derivatives with a wide range of functional groups was synthesized in up to 97% yield. With this new method, every position in the final product can be substituted which renders the method ideal for applications in combinatorial or medicinal chemistry. PMID:26691580

  14. One-Pot C-H Functionalization of Arenes by Diaryliodonium Salts.

    PubMed

    Reitti, Marcus; Villo, Piret; Olofsson, Berit

    2016-07-25

    A transition-metal-free, mild, and highly regioselective synthesis of nitroarenes from arenes has been developed. The products are obtained in a sequential one-pot reaction by nitration of iodine(III) reagents with two carbon ligands, which are formed in situ from iodine(I). This novel concept has been extended to formation of aryl azides, and constitutes an important step towards catalytic reactions with these hypervalent iodine reagents. An efficient nitration of isolated diaryliodonium salts has also been developed, and the mechanism is proposed to proceed by a [2,2] ligand coupling pathway. PMID:27272891

  15. 1,2-Thiazines: One-Pot Syntheses Utilizing Mono and Diaza Analogs of Sulfones.

    PubMed

    Bohmann, Rebekka Anna; Unoh, Yuto; Miura, Masahiro; Bolm, Carsten

    2016-05-10

    A one-pot Michael addition/cyclization/condensation reaction sequence for the regioselective synthesis of 1,2-thiazines, starting from propargyl ketones and NH-sulfoximines or NH-sulfondiimines, has been developed. Under mild and operationally simple reaction conditions previously unprecedented 1,2-thiazine 1-imide and 1-oxide derivatives are formed in good to excellent yields. The products represent heterocyclic building blocks, readily modifiable by a regioselective C-H bond functionalization, classical cross-coupling reactions, and deprotection. PMID:26991757

  16. One-pot oxidation and rearrangement of propargylamines and in situ pyrazole synthesis.

    PubMed

    Chen, Jinshan; Properzi, Roberta; Uccello, Daniel P; Young, Jennifer A; Dushin, Russell G; Starr, Jeremy T

    2014-08-15

    Reported here are procedures for a one-pot oxidation and rearrangement of propargylamines to synthesize enaminones, with supporting mechanistic studies. Also reported are the extended one-pot syntheses of pyrazoles, including celecoxib and various heterocyclic compounds. PMID:25069029

  17. One-pot synthesis of chemically modified vegetable oils.

    PubMed

    Sharma, Brajendra K; Liu, Zengshe; Adhvaryu, Atanu; Erhan, Sevim Z

    2008-05-14

    Vegetable oils are promising candidates as substitutes for petroleum base oils in lubricant applications, such as total loss lubrication, military applications, and outdoor activities. Although vegetable oils have some advantages, they also have poor oxidation and low temperature stability. One of the ways to address these issues is chemical modification of fatty acid chain of triglyceride. We report a one-pot synthesis of a novel class of chemically modified vegetable oils from epoxidized triacylglycerols and various anhydrides. In an anhydrous solvent, boron trifluoride etherate is used as catalyst to simultaneously open the oxirane ring and activate the anhydride. The reaction was monitored and products confirmed by NMR, FTIR, GPC, and TGA analysis. Experimental conditions were optimized for research quantity and laboratory scale-up (up to 4 lbs). The resultant acyl derivatives of vegetable oil, having diester substitution at the sites of unsaturation, have potential in formulation of industrial fluids such as hydraulic fluids, lubricants, and metal working fluids. PMID:18399638

  18. One-pot synthesis of (−)-Ambrox

    PubMed Central

    Yang, Shaoxiang; Tian, Hongyu; Sun, Baoguo; Liu, Yongguo; Hao, Yanfeng; Lv, Yanyu

    2016-01-01

    (−)-Ambrox is recognised as the prototype of all ambergris odorants. Widely used in perfumery, (−)-Ambrox is an important ingredient due to its unique scent and excellent fixative function. An environmentally friendly and practical preparation of (−)-Ambrox is still unavailable at present although a lot of attention has been paid to this hot research topic for many years. A one-pot synthesis of (−)-Ambrox was studied starting from (−)-sclareol through oxidation with hydrogen peroxide in the presence of a quaternary ammonium phosphomolybdate catalyst {[C5H5NC16H33] [H2PMo12O40]}, which gave the product a 20% overall yield. PMID:27581945

  19. Multi-catalysis reactions: direct organocatalytic sequential one-pot synthesis of highly functionalized cyclopenta[b]chromen-1-ones.

    PubMed

    Ramachary, Dhevalapally B; Reddy, Y Vijayendar; Kishor, Mamillapalli

    2008-11-21

    We have developed a new technology called multi-catalysis for the sequential one-pot synthesis of highly functionalized heterocycles. A practical and novel multi-component aniline-, self- and Brønsted acid-catalyzed selective process for the sequential one-pot synthesis of highly substituted 2-(2-hydroxy-aryl)-cyclopentane-1,3-diones, 3,9-dihydro-2H-cyclopenta[b]chromen-1-ones and 3,3-dimethyl-2,3,4,9-tetrahydro-xanthen-1-ones is reported. Direct combination of aniline- and self-catalyzed cascade olefination-hydrogenation (O-H) and Brønsted acid-catalyzed cascade oxy-Michael-dehydration (OM-DH) of 1,3-diones, salicylic aldehydes and organic-hydrides is developed in one-pot to furnish the highly functionalized 3,9-dihydro-2H-cyclopenta[b]chromen-1-ones and 3,3-dimethyl-2,3,4,9-tetrahydro-xanthen-1-ones with high yields. PMID:18972049

  20. A Novel and Facile One-Pot Solvothermal Synthesis of PEDOT-PSS/Ni-Mn-Co-O Hybrid as an Advanced Supercapacitor Electrode Material.

    PubMed

    Yin, Chengjie; Yang, Chunming; Jiang, Min; Deng, Cuifen; Yang, Lishan; Li, Junhua; Qian, Dong

    2016-02-01

    In this work, a novel and facile one-pot method has been developed for the synthesis of a hybrid consisting of Ni-Mn-Co ternary oxide and poly(3,4-ethylenedioxythiophene)-polystyrenesulfonate (PEDOT-PSS/NMCO) with a hierarchical three-dimensional net structure via a solvothermal-coprecipitation coupled with oxidative polymerization route. Apart from the achievement of polymerization, coprecipitation, and solvothermal in one pot, the hydroxyl (OH(-)) ions generated from the oxidative polymerization of organic monomer by neutral KMnO4 solution were skillfully employed as precipitants for metal ions. As compared with the PEDOT-PSS/Ni-Mn binary oxide, PEDOT-PSS/Co-Mn binary oxide, and PEDOT-PSS/MnO2, PEDOT-PSS1.5/NMCO exhibits overwhelmingly superior supercapacitive performance, more specifically, a high specific capacitance of 1234.5 F g(-1) at a current density of 1 A g(-1), a good capacitance retention of 83.7% at a high current density of 5 A g(-1) after 1000 cycles, an energy density of 51.9 W h kg(-1) at a power density of 275 W kg(-1), and an energy density of 21.4 W h kg(-1) at an extremely elevated power density of 5500 W kg(-1). Noticeably, the energy density and power density of PEDOT-PSS/NMCO are by far higher than those of the existing analogues recently reported. The exceptional performance of PEDOT-PSS/NMCO benefits from its unique mesoporous architecture, which could provide a larger reaction surface area, faster ion and electron transfer ability, and good structural stability. The desirable integrated performance enables the multicomponent composite to be a promising electrode material for energy storage applications. PMID:26794146

  1. Coupling Oxygen Consumption with Hydrocarbon Oxidation in Bacterial Multicomponent Monooxygenases.

    PubMed

    Wang, Weixue; Liang, Alexandria D; Lippard, Stephen J

    2015-09-15

    A fundamental goal in catalysis is the coupling of multiple reactions to yield a desired product. Enzymes have evolved elegant approaches to address this grand challenge. A salient example is the biological conversion of methane to methanol catalyzed by soluble methane monooxygenase (sMMO), a member of the bacterial multicomponent monooxygenase (BMM) superfamily. sMMO is a dynamic protein complex of three components: a hydroxylase, a reductase, and a regulatory protein. The active site, a carboxylate-rich non-heme diiron center, is buried inside the 251 kDa hydroxylase component. The enzyme processes four substrates: O2, protons, electrons, and methane. To couple O2 activation to methane oxidation, timely control of substrate access to the active site is critical. Recent studies of sMMO, as well as its homologues in the BMM superfamily, have begun to unravel the mechanism. The emerging and unifying picture reveals that each substrate gains access to the active site along a specific pathway through the hydroxylase. Electrons and protons are delivered via a three-amino-acid pore located adjacent to the diiron center; O2 migrates via a series of hydrophobic cavities; and hydrocarbon substrates reach the active site through a channel or linked set of cavities. The gating of these pathways mediates entry of each substrate to the diiron active site in a timed sequence and is coordinated by dynamic interactions with the other component proteins. The result is coupling of dioxygen consumption with hydrocarbon oxidation, avoiding unproductive oxidation of the reductant rather than the desired hydrocarbon. To initiate catalysis, the reductase delivers two electrons to the diiron(III) center by binding over the pore of the hydroxylase. The regulatory component then displaces the reductase, docking onto the same surface of the hydroxylase. Formation of the hydroxylase-regulatory component complex (i) induces conformational changes of pore residues that may bring protons to the

  2. Graphite-supported perchloric acid (HClO4-C): an efficient and recyclable heterogeneous catalyst for the one-pot synthesis of amidoalkyl naphthols.

    PubMed

    Lei, Zhen-Kai; Xiao, Li; Lu, Xiao-Quan; Huang, He; Liu, Chen-Jiang

    2013-01-01

    An efficient and direct protocol for the preparation of amidoalkylnaphthols employing a multi-component, one-pot condensation reaction of 2-naphthol, aromatic aldehydes and acetamide or benzamide in the presence of graphite supported perchloric acid under solvent-free conditions is described. The thermal solvent-free procedure offers advantages such as simple work-up, shorter reaction times and higher product yields, and the catalyst exhibited remarkable reactivity and can be recycled. PMID:23358323

  3. One-pot conversions of lignocellulosic and algal biomass into liquid fuels.

    PubMed

    De, Sudipta; Dutta, Saikat; Saha, Basudeb

    2012-09-01

    The one-pot conversion of lignocellulosic and algal biomass into a liquid fuel, 2,5-dimethylfuran (DMF), has been achieved by using a multicomponent catalytic system comprising [DMA]⁺ [CH₃SO₃]⁻ (DMA=N,N-dimethylacetamide), Ru/C, and formic acid. The synthesis of DMF from all substrates was carried out under mild reaction conditions. The reaction progressed via 5-hydroxyemthylfurfural (HMF) in the first step followed by hydrogenation and hydrogenolysis of HMF with the Ru/C catalyst and formic acid as a hydrogen source. This report discloses the effectiveness of the Ru/C catalyst for the first time for DMF synthesis from inexpensive and readily abundant biomass sources, which gives a maximum yield of 32 % DMF in 1 h. A reaction route involving 5-(formyloxymethyl)furfural (FMF) as an intermediate has been elucidated based on the ¹H and ¹³C NMR spectroscopic data. Another promising biofuel, 5-ethoxymethylfurfural (EMF), was also synthesized with high selectivity from polymeric carbohydrate-rich biomass substrates by using a Brønsted acidic ionic liquid catalyst, that is [DMA]⁺ [CH₃SO₃]⁻, by etherification of HMF in ethanol. PMID:22639414

  4. One-Pot Three-Component Condensation Synthesis and Structural Features of Organophosphorus-Sulfur Macrocycles.

    PubMed

    Hua, Guoxiong; Du, Junyi; Cordes, David B; Slawin, Alexandra M Z; Woollins, J Derek

    2016-05-20

    A new preparative route was developed to synthesize new phosphorus-sulfur [SP(═S)S moiety]-containing macrocycles via a one-pot and three-component domino reaction of four-membered ring thionation reagents such as 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (LR, Lawesson's reagent) and 2,4-diferrocenyl-1,3,2,4-diathiadiphosphetane 2,4-disulfide (FcLR, a ferrocene analogue of Lawesson's reagent) and alkyldithiols(aryldithols) and dihaloalkanes in the presence of sodium hydride. Therefore, a series of 12- to 18-membered macrocycles incorporating two phosphorus and six sulfur atoms were synthesized. The synthesis features a novel application of the multicomponent reaction, providing an efficient route to the preparation of the new phosphorus-sulfur-containing macrocycles. Seven representative X-ray structures confirm the formation of these macrocycles and show the presence of a number of the intramolecular C-H···S hydrogen bonding, intermolecular C-H···S, C-H···Cl, and Cl···Cl short contacts and π-stacking interactions in their 3D network structures. PMID:27135838

  5. Development of the Multicomponent Coupled-Cluster Theory for Investigation of Multiexcitonic Interactions.

    PubMed

    Ellis, Benjamin H; Aggarwal, Somil; Chakraborty, Arindam

    2016-01-12

    Multicomponent systems are defined as chemical systems that require a quantum mechanical description of two or more different types of particles. Non-Born-Oppenheimer electron-nuclear interactions in molecules, electron-hole interactions in electronically excited nanoparticles, and electron-positron interactions are examples of physical systems that require a multicomponent quantum mechanical formalism. The central challenge in the theoretical treatment of multicomponent systems is capturing the many-body correlation effects that exist not only between particles of identical types (electron-electron) but also between particles of different types (electron-nuclear and electron-hole). In this work, the development and implementation of multicomponent coupled-cluster (mcCC) theory for treating particle-particle correlation in multicomponent systems are presented. This method provides a balanced treatment of many-particle correlation effects in a general multicomponent system while maintaining a size-consistent and size-extensive formalism. The coupled-cluster ansatz presented here is an extension of the electronic structure CCSD formulation for multicomponent systems and is defined as |ΨmcCC⟩ = eT1I+T2I+T1II+T2II+T11I,II+T12I,II+T21I,II+T22I,II|0I0II⟩. The cluster amplitudes in the mcCC wave function were obtained by projecting the mcCC Schrödinger equation onto a direct product space of singly and doubly excited states of type I and II particles and then solving the resulting mcCC equations iteratively. These equations were derived using an automated application of the generalized Wick’s theorem and were implemented using a computer-assisted source code generation approach. The applicability of the mcCC method was demonstrated by calculating ground state energies of multicomponent Hooke's atom and positronium hydride systems as well as by calculating exciton and biexciton binding energies in multiexcitonic systems. For each case, the mcCC results were

  6. Preparation of magnetic resonance probes using one-pot method for detection of hepatocellular carcinoma

    PubMed Central

    Li, You-Wei; Chen, Zheng-Guang; Zhao, Zhou-She; Li, Hong-Li; Wang, Ji-Chen; Zhang, Zong-Ming

    2015-01-01

    AIM: To prepare the specific magnetic resonance (MR) probes for detection of hepatocellular carcinoma (HCC) using one-pot method. METHODS: The carboxylated dextran-coated nanoparticles were conjugated with anti-α-fetoprotein (anti-AFP) or anti-glypican 3 (anti-GPC3) antibodies through 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS)-mediated reaction to synthesize the probes. The physical and chemical properties of the probes were determined by transmission electron microscopy (TEM) and dynamic light scattering, and the relaxivity was compared to uncombined ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs) using a 1.5T clinical MR scanner. The binding efficiency of the antibodies to nanoparticles was measured with an ultraviolet-visible spectrophotometer. In addition, the probes were incubated with targetable cells in vitro. RESULTS: The superparamagnetic MR probes (anti-GPC3-USPION probe and anti-AFP-USPION probe) were synthesized using one-pot method. Their mean hydrodynamic diameter was 47 nm with a broader slight size distribution. The coupling efficiency of carboxylated dextran-coated ultrasmall superparamagnetic iron oxide (USPIO) with anti-GPC3 or anti-AFP antibody was 15.9% and 88.8%, respectively. Each of the USPIO nanoparticles may bind 3 GPC3 antibodies or 12 AFP antibodies. The statistical analysis showed no significance (P > 0.05) in shortening the T1 and T2 values when comparing the USPIO-AFP or USPIO-GPC3 to USPIO. Analysis of TEM images revealed that anti-GPC3-USPION probes and anti-AFP-USPION probes could specifically enter into the HepG2 cell by combining with the GPC3 receptors or AFP receptors, whereas the HepG2 cell sample incubated with USPIONs showed no or few nanoparticles in the cytoplasm. CONCLUSION: The synthesized probes using one-pot method can be used for in vitro experimental study and have potential clinical application in MR imaging for detection of hepatocellular carcinomas

  7. Palladium-Catalyzed One-Pot Reaction of Hydrazones, Dihaloarenes, and Organoboron Reagents: Synthesis and Cytotoxic Activity of 1,1-Diarylethylene Derivatives.

    PubMed

    Roche, Maxime; Salim, Salim Mmadi; Bignon, Jérôme; Levaique, Hélène; Brion, Jean-Daniel; Alami, Mouad; Hamze, Abdallah

    2015-07-01

    A new three-component assembly reaction between N-tosylhydrazones, dihalogenated arenes, and boronic acids or boronate esters was developed, producing highly substituted 1,1-diarylethylenes in good yields. The two C-C bonds formed through this coupling have been catalyzed by a single Pd-catalyst in a one-pot fashion. It is noted that the one-pot pinacol boronate cross-coupling reaction generally provides products in high yields, offers an expansive substrate scope, and can address a broad range of aryl, styrene, vinyl, and heterocyclic olefinic targets. The scope of this one-pot coupling has been also extended to the synthesis of the 1,1-diarylethylene skeleton of the natural product ratanhine. The new compounds were evaluated for their cytotoxic activity, and this allowed the identification of compound 4ab that exhibits excellent antiproliferative activity in the nanomolar concentration range against HCT116 cancer cell lines. PMID:26036279

  8. A One-Pot, Asymmetric Robinson Annulation in the Organic Chemistry Majors Laboratory

    ERIC Educational Resources Information Center

    Lazarski, Kiel E.; Rich, Alan A.; Mascarenhas, Cheryl M.

    2008-01-01

    The Robinson annulation is a topic of importance in the second-year organic curriculum. A one-pot, enantioselective Robinson annulation is described. The experiment is completed in two lab periods and is geared towards the second-year organic chemistry major. To our knowledge, this is the first example of a one-pot enantioselective Robinson…

  9. Tandem buildup of complexity of aromatic molecules through multiple successive electrophile generation in one pot, controlled by varying the reaction temperature.

    PubMed

    Sumita, Akinari; Otani, Yuko; Ohwada, Tomohiko

    2016-02-01

    While some sequential electrophilic aromatic substitution reactions, known as tandem/domino/cascade reactions, have been reported for the construction of aromatic single skeletons, one of the most interesting and challenging possibilities remains the one-pot build-up of a complex aromatic molecule from multiple starting components, i.e., ultimately multi-component electrophilic aromatic substitution reactions. In this work, we show how tuning of the leaving group ability of phenolate derivatives from carbamates and esters provides a way to successively generate multiple unmasked electrophiles in a controlled manner in one pot, simply by varying the temperature. Here, we demonstrate the autonomous formation of up to three bonds in one pot and formation of two bonds arising from a three-component electrophilic aromatic substitution reaction. This result provides a proof-of-concept of our strategy applicable for the self-directed construction of complex aromatic structures from multiple simple molecules, which can be a potential avenue to realize multi-component electrophilic aromatic substitution reactions. PMID:26699842

  10. Vanillic aldehydes for the one-pot synthesis of novel 2-oxo-1,2,3,4-tetrahydropyrimidines.

    PubMed

    Muškinja, Jovana; Janković, Nenad; Ratković, Zoran; Bogdanović, Goran; Bugarčić, Zorica

    2016-08-01

    A small library of novel 2-oxo-1,2,3,4-tetrahydropyrimidines was synthesized via a one-pot multicomponent Biginelli reaction. Copper complex [Formula: see text] which was used for the first time as a homogeneous and heterogeneous catalyst, makes this a facile and efficient reaction at room temperature. All the obtained products fall out of the solution in pure form and are easily isolated via filtration in good-to-excellent yields. The molecular structure of one of the products, ethyl 6-methyl-2-oxo-4-(4[Formula: see text]-isopropoxy-3[Formula: see text]-methoxyphenyl) - 1,2,3,4 - tetrahydropyrimidine-5- carboxylate, has been determined by X-ray crystallography. All non-hydrogen atoms in the heterocyclic, six-membered ring are determined to be approximately coplanar. PMID:26829937

  11. A novel protocol for the one-pot borylation/Suzuki reaction provides easy access to hinge-binding groups for kinase inhibitors.

    PubMed

    Hooper, A; Zambon, A; Springer, C J

    2016-01-21

    The one-pot borylation/Suzuki reaction is a very efficient means of accessing cross-coupling products of two aryl-halide partners that generally requires the use of specific catalysts or ligands and/or relatively long reaction times. This new microwave-assisted method provides a quick one-pot borylation/Suzuki reaction protocol that we applied to the synthesis of various bi- or poly-aryl scaffolds, including a variety of aryl and heteroaryl ring systems and the core frameworks of kinase inhibitors vemurafenib and GDC-0879. PMID:26620576

  12. Transition metal-catalyzed one-pot synthesis of water-soluble dendritic molecular nanocarriers.

    PubMed

    Chen, Guanghui; Guan, Zhibin

    2004-03-10

    Here, we report the first example of transition metal-catalyzed one-pot synthesis of water-soluble dendritic molecular nanocarriers behaving like unimolecular micelles. Using the palladium-alpha-diimine chain walking catalyst, copolymerization of ethylene and comonomer 3 afforded, in one step, amphiphilic copolymer 1 having a hydrophobic core and a hydrophilic shell. A much larger amphiphilic core-shell copolymer 2 was synthesized by a two-step approach: a copolymer having many free hydroxyl groups was first prepared, which was subsequently coupled to poly(ethylene glycol) (PEG) to afford the copolymer 2. Light-scattering, fluorescence, and UV/vis spectroscopic studies with Nile Red in aqueous solution showed unimolecular micellar properties for both copolymers 1 and 2. The dye encapsulation capacity for the core-shell copolymers is nearly proportional to the molecular weight of the hydrophobic core. The unimolecular micellar properties coupled with the good water solubility and biocompatibility of the PEG moieties make these molecular nanocarriers promising candidates for many applications including drug delivery and controlled drug release. PMID:14995158

  13. One-pot synthesis of quinazolinones via iridium-catalyzed hydrogen transfers.

    PubMed

    Zhou, Jianguang; Fang, Jie

    2011-10-01

    A one-pot oxidative cyclization of primary alcohols with o-aminobenzamides to quinazolinones was successfully achieved using [Cp*IrCl(2)](2) (Cp* = pentamethylcyclopentadienyl) as a catalyst under hydrogen transfer conditions. PMID:21851120

  14. Combined Pd/C and Montmorillonite Catalysis for One-Pot Synthesis of Benzimidazoles.

    PubMed

    Weires, Nicholas A; Boster, Jared; Magolan, Jakob

    2012-11-01

    A series of nineteen benzimidazoles are prepared from ortho-nitroanilines via one-pot transfer hydrogenation, condensation, and dehydrogenation enabled by the concurrent use of two heterogeneous catalysts: montmorillonite-K10 and Pd/C. This strategy is further employed to accomplish a five-step, three-component synthesis of an antifungal benzimidazoquinazoline using a simple one-pot procedure. PMID:23525858

  15. Combined Pd/C and Montmorillonite Catalysis for One-Pot Synthesis of Benzimidazoles

    PubMed Central

    Weires, Nicholas A.; Boster, Jared; Magolan, Jakob

    2013-01-01

    A series of nineteen benzimidazoles are prepared from ortho-nitroanilines via one-pot transfer hydrogenation, condensation, and dehydrogenation enabled by the concurrent use of two heterogeneous catalysts: montmorillonite-K10 and Pd/C. This strategy is further employed to accomplish a five-step, three-component synthesis of an antifungal benzimidazoquinazoline using a simple one-pot procedure. PMID:23525858

  16. Multi-component ground motion response spectra for coupled horizontal, vertical, angular accelerations, and tilt

    USGS Publications Warehouse

    Kalkan, E.; Graizer, V.

    2007-01-01

    Rotational and vertical components of ground motion are almost always ignored in design or in the assessment of structures despite the fact that vertical motion can be twice as much as the horizontal motion and may exceed 2g level, and rotational excitation may reach few degrees in the proximity of fault rupture. Coupling of different components of ground excitation may significantly amplify the seismic demand by introducing additional lateral forces and enhanced P-?? effects. In this paper, a governing equation of motion is postulated to compute the response of a SDOF oscillator under a multi-component excitation. The expanded equation includes secondary P-?? components associated with the combined impacts of tilt and vertical excitations in addition to the inertial forcing terms due to the angular and translational accelerations. The elastic and inelastic spectral ordinates traditionally generated considering the uniaxial input motion are compared at the end with the multi-component response spectra of coupled horizontal, vertical and tilting motions. The proposed multi-component response spectrum reflects kinematic characteristics of the ground motion that are not identifiable by the conventional spectrum itself, at least for the near-fault region where high intensity vertical shaking and rotational excitation are likely to occur.

  17. One-pot synthesis of tetracyclic fused imidazo[1,2-a]pyridines via a three-component reaction

    PubMed Central

    Yang, Bo; Tao, Chuanye; Shao, Taofeng

    2016-01-01

    Summary A novel three-component reaction has been developed to assemble biologically and pharmaceutically important tetracyclic fused imidazo[1,2-a]pyridines in a one-pot fashion utilizing readily available 2-aminopyridines, isatins and isocyanides. The three-component coupling proceeds through the Groebke–Blackburn–Bienaymé reaction followed by a retro-aza-ene reaction and subsequent nucleophilic reaction of the in-situ generated imidazo[1,2-a]pyridines bearing an isocyanate functional group. PMID:27559401

  18. Efficient one-pot synthesis of amino-benzotriazolodiazocinone scaffolds via catalyst-free tandem Ugi-Huisgen reactions.

    PubMed

    Barlow, T M A; Jida, M; Guillemyn, K; Tourwé, D; Caveliers, V; Ballet, S

    2016-05-18

    Herein we describe a catalyst-free, one-pot procedure employing an Ugi-4CR between propargyl glycine, functionalised 2-azidoanilines, different isocyanides and aldehydes, followed by a thermal azide-alkyne Huisgen cycloaddition to generate a 14-member set of amino-benzotriazolodiazocine-bearing dipeptides with multiple points of diversification and high atom economy. These structures were derivatized by means of Suzuki-Miyaura cross-coupling reactions at two positions with good to excellent yields, leading to conformationally constrained tricyclic structures. In silico and NMR conformational analysis studies demonstrated that turn conformations are adopted by these structures. PMID:27117259

  19. One-pot synthesis of tetracyclic fused imidazo[1,2-a]pyridines via a three-component reaction.

    PubMed

    Yang, Bo; Tao, Chuanye; Shao, Taofeng; Gong, Jianxian; Che, Chao

    2016-01-01

    A novel three-component reaction has been developed to assemble biologically and pharmaceutically important tetracyclic fused imidazo[1,2-a]pyridines in a one-pot fashion utilizing readily available 2-aminopyridines, isatins and isocyanides. The three-component coupling proceeds through the Groebke-Blackburn-Bienaymé reaction followed by a retro-aza-ene reaction and subsequent nucleophilic reaction of the in-situ generated imidazo[1,2-a]pyridines bearing an isocyanate functional group. PMID:27559401

  20. One-pot, three-component approach to the synthesis of 3,4,5-trisubstituted pyrazoles.

    PubMed

    Kamal, Ahmed; Sastry, K N Visweswara; Chandrasekhar, D; Mani, Geeta Sai; Adiyala, Praveen Reddy; Nanubolu, Jagadeesh Babu; Singarapu, Kiran Kumar; Maurya, Ram Awatar

    2015-05-01

    An operationally simple and high yielding protocol for the synthesis of polyfunctional pyrazoles has been developed through one-pot, three-component coupling of aldehydes, 1,3-dicarbonyls, and diazo compounds as well as tosyl hydrazones. The reaction proceeds through a tandem Knoevenagel condensation, 1,3-dipolar cycloaddition, and transition metal-free oxidative aromatization reaction sequence utilizing molecular oxygen as a green oxidant. The scope of the reaction was studied by varying the aldehyde, 1,3-dicarbonyl, and diazo component individually. PMID:25849582

  1. Measurement of the acoustic-to-optical phonon coupling in multicomponent systems

    NASA Astrophysics Data System (ADS)

    Caretta, Antonio; Donker, Michiel C.; Perdok, Diederik W.; Abbaszadeh, Davood; Polyakov, Alexey O.; Havenith, Remco W. A.; Palstra, Thomas T. M.; van Loosdrecht, Paul H. M.

    2015-02-01

    In this paper we investigate the acoustic-to-optical up-conversion phonon processes in a multicomponent system. These processes take place during heat transport and limit the efficiency of heat flow. By combining time-resolved optical and heat capacity experiments we quantify the thermal coupling constant to be g ˜0.4 1017 W/Km3 . The method is based on selective excitation of a part of a multicomponent system, and the measurement of the thermalization dynamics by probing the linear birefringence of the sample with femtosecond resolution. In particular, we study a layered multiferroic organic-inorganic hybrid, in the vicinity of the ferroelectric phase transition. A diverging term of the heat capacity is associated to soft-mode dynamics, in agreement with previous spectroscopy measurements.

  2. A semi-discrete integrable multi-component coherently coupled nonlinear Schrödinger system

    NASA Astrophysics Data System (ADS)

    Zhao, Hai-qiong; Yuan, Jinyun

    2016-07-01

    A new integrable semi-discrete version is proposed for the multi-component coherently coupled nonlinear Schrödinger equation. The integrability of the semi-discrete system is confirmed by existence of Lax pair and infinite number of conservation laws. With the aid of gauge transformations, explicit formulas for N-fold Darboux transformations are derived whereby some physically important solutions of the system are presented. Furthermore, the theory of the semi-discrete system including Lax pair, Darboux transformations, exact solutions and infinite number of conservation laws are shown for their continuous counterparts in the continuous limit.

  3. Coupled discretization of multicomponent diffusion problems in equilibrium and non-equilibrium plasmas

    NASA Astrophysics Data System (ADS)

    Peerenboom, Kim; Ten Thije Boonkkamp, Jan; van Dijk, Jan; Kroesen, Gerrit

    2013-09-01

    Solving balance equations is the essence of any fluid simulation of reactive, multicomponent plasmas. For plasmas in chemical non-equilibrium, balance equations are solved for all species of interest. When reactions are very fast with respect to transport time scales - and the plasma approaches chemical equilibrium - species abundances can be obtained from equilibrium relations. However, in many cases, balance equations still need to be solved for the elements, since the elemental composition can vary significantly in reactive multicomponent plasmas. Both in equilibrium and in non-equilibrium the species diffusive fluxes in these balance equations are governed by the Stefan-Maxwell equations. The use of Stefan-Maxwell diffusion leads to a coupled set of balance equations. Furthermore, this coupled set of equations is subject to charge and mass conservation constraints. Due to these complications the set of balance equations is often artificially decoupled to fit in the traditional finite volume discretization schemes and the constraints are explicitly applied. This approach can lead to very poor convergence behavior. We will present a new approach using a finite volume discretization scheme that takes into account the coupling and treats the constraints implicitly.

  4. One-Pot Aminoethylation of Indoles/Pyrroles with Alkynes and Sulfonyl Azides.

    PubMed

    Rajasekar, Shanmugam; Yadagiri, Dongari; Anbarasan, Pazhamalai

    2015-11-16

    A general and efficient one-pot aminoethylation of substituted indoles/pyrroles was accomplished for the synthesis of various tryptamine derivatives employing a combination of alkynes and sulfonyl azides as readily accessible aminoethylating agents. The reaction features a successful integration of copper-catalyzed alkyne and azide cycloaddition to N-sulfonyl-1,2,3-triazole, rhodium-catalyzed selective insertion of α-iminocarbenes onto the C3-H bond of indoles, and reduction of the resultant enamides to tryptamine derivatives employing either NaCNBH3 or palladium catalyst, in one-pot. The reaction also showed excellent functional-group tolerance and allowed the synthesis of various substituted tryptamines in good to excellent yield. This transformation constitutes a one-pot formal regioselective functionalization of terminal alkynes. Utility of the synthesized tryptamine was further demonstrated in the synthesis of dihydro-β-carboline and tryptoline. PMID:26443500

  5. Multi-Component Reactions in Heterocyclic Chemistry

    NASA Astrophysics Data System (ADS)

    Müller, Thomas J. J.; Orru, Romano V. A.; Chebanov, Valentin A.; Sakhno, Yana I.; Saraev, Vyacheslav E.; Muravyova, Elena A.; Andrushchenko, Anastasia Yu.; Desenko, Sergey M.; Akhmetova, V. R.; Khabibullina, G. R.; Rakhimova, E. B.; Vagapov, R. A.; Khairullina, R. R.; Niatshina, Z. T.; Murzakova, N. N.; Maslivets, Andrey N.; Voskressensky, Leonid G.; Danagulyan, Gevorg G.; Murtchyan, Armen D.; Tumanyan, Araksya K.; Banfi, Luca; Basso, Andrea; de Moliner, Fabio; Guanti, Giuseppe; Petricci, Elena; Riva, Renata; Taddei, Maurizio; Naimi-Jamal, M. Reza; Mashkouri, Sara; Sharifi, Ali; Przhevalski, Nikolai M.; Rozhkova, Elena N.; Tokmakov, Gennadii P.; Magedov, Igor V.; Armisheva, M. N.; Rassudihina, N. A.; Vahrin, M. I.; Gein, V. L.; Shaabani, Ahmad; Rezayan, Ali Hossein; Sarvary, Afshin; Heidary, Marjan; Ng, Seik Weng; Beliaev, Nikolai A.; Mokrushin, Vladimir S.; Paramonov, Igor V.; Ilyin, Alexey; Garkushenko, Anna K.; Dushek, Maria A.; Sagitullina, Galina P.; Sagitullin, Reva S.; Kysil, Volodymyr; Khvat, Alexander; Tsirulnikov, Sergey; Tkachenko, Sergey; Ivachtchenko, Alexandre; Gein, Vladimir L.; Panova, Olga S.; Ilyn, Alexey P.; Kravchenko, Dmitri V.; Potapov, Victor V.; Ivachtchenko, Alexandre V.; Vichegjanina, V. N.; Levandovskaya, E. B.; Gein, V. L.; Vahrin, M. I.; Vladimirov, I. N.; Zorina, A. A.; Nosova, N. V.; Gein, V. L.; Fedorova, O. V.; Vahrin, M. I.

    Multi-component and domino reactions are efficient and effective methods in the sustainable and diversity-oriented synthesis of heterocycles. In particular, transition metal-catalyzed multi-component sequences have recently gained considerable interest. Based upon the Sonogashira entry to alkynones, alkenones, and intermediate allenes, we have opened new avenues to the one-pot synthesis of numerous classes of heterocyclic frameworks in an MCR fashion. This methodological approach has now found various applications in one-pot syntheses of functional chromophores, pharmaceutically active compounds, and marine alkaloids and derivatives.

  6. Thiazolidine-Protected β-Thiol Asparagine: Applications in One-Pot Ligation-Desulfurization Chemistry.

    PubMed

    Sayers, Jessica; Thompson, Robert E; Perry, Kristen J; Malins, Lara R; Payne, Richard J

    2015-10-01

    The synthesis of a β-thiol asparagine derivative bearing a novel (2,4,6-trimethoxyphenyl)thiazolidine protecting group is described. The efficient incorporation of the amino acid into the N-termini of peptides is demonstrated as well as the utility of the β-thiol asparagine moiety for rapid ligation reactions with peptide thioesters. The streamlined synthesis of native peptide products could be accomplished using a one-pot radical desulfurization of the β-thiol auxiliary following the ligation event. The utility of the amino acid is highlighted in the efficient one-pot assembly of the HIV entry inhibitor enfuvirtide. PMID:26398220

  7. Anomeric Reactivity-Based One-Pot Synthesis of Heparin-Like Oligosaccharides

    PubMed Central

    Polat, Tülay

    2008-01-01

    A highly efficient one-pot methodology is described for the synthesis of heparin and heparan sulfate oligosaccharides utilizing thioglycosides with well defined reactivity as building blocks. l-idopyranosyl and d-glucopyranosyl thioglycosides 5 and 10 were used as donors due to low reactivity of uronic acids as the glycosyl donors in the one-pot synthesis. The formation of uronic acids by a selective oxidation at C-6 was performed after assembly of the oligosaccharides. The efficiency of this strategy with the flexibility for sulfate incorporation was demonstrated in the representative synthesis of disaccharides 17, 18, tetrasaccharide 23 and pentasaccharide 26. PMID:17914818

  8. Silyl Glyoxylates. Conception and Realization of Flexible Conjunctive Reagents for Multicomponent Coupling

    PubMed Central

    Boyce, Gregory R.; Greszler, Stephen N.; Linghu, Xin; Malinowski, Justin T.; Nicewicz, David A.; Satterfield, Andrew D.; Schmitt, Daniel C.; Steward, Kimberly M.

    2012-01-01

    This Perspective describes the discovery and development of silyl glyoxylates, a new family of conjunctive reagents for use in multicomponent coupling reactions. The selection of the nucleophilic and electrophilic components determines whether the silyl glyoxylate reagent will function as a synthetic equivalent to the dipolar glycolic acid synthon, the glyoxylate anion synthon, or the α-keto ester homoenolate synthon. The ability to select for any of these reaction modes has translated to excellent structural diversity in the derived three- and four-component coupling adducts. Preliminary findings on the development of catalytic reactions using these reagents are detailed, as are the design and discovery of new reactions directed toward particular functional group arrays embedded within bioactive natural products. PMID:22414181

  9. PdCo/Pd-Hexacyanocobaltate Hybrid Nanoflowers: Cyanogel-Bridged One-Pot Synthesis and Their Enhanced Catalytic Performance

    PubMed Central

    Liu, Zhen-Yuan; Fu, Geng-Tao; Zhang, Lu; Yang, Xiao-Yu; Liu, Zhen-Qi; Sun, Dong-Mei; Xu, Lin; Tang, Ya-Wen

    2016-01-01

    Elaborate architectural manipulation of nanohybrids with multi-components into controllable 3D hierarchical structures is of great significance for both fundamental scientific interest and realization of various functionalities, yet remains a great challenge because different materials with distinct physical/chemical properties could hardly be incorporated simultaneously into the synthesis process. Here, we develop a novel one-pot cyanogel-bridged synthetic approach for the generation of 3D flower-like metal/Prussian blue analogue nanohybrids, namely PdCo/Pd-hexacyanocobaltate for the first time. The judicious introduction of polyethylene glycol (PEG) and the formation of cyanogel are prerequisite for the successful fabrication of such fascinating hierarchical nanostructures. Due to the unique 3D hierarchical structure and the synergistic effect between hybrid components, the as-prepared hybrid nanoflowers exhibit a remarkable catalytic activity and durability toward the reduction of Rhodamine B (RhB) by NaBH4. We expect that the obtained hybrid nanoflowers may hold great promises in water remediation field and beyond. Furthermore, the facile synthetic strategy presented here for synthesizing functional hybrid materials can be extendable for the synthesis of various functional hybrid nanomaterials owing to its versatility and feasibility. PMID:27573057

  10. PdCo/Pd-Hexacyanocobaltate Hybrid Nanoflowers: Cyanogel-Bridged One-Pot Synthesis and Their Enhanced Catalytic Performance.

    PubMed

    Liu, Zhen-Yuan; Fu, Geng-Tao; Zhang, Lu; Yang, Xiao-Yu; Liu, Zhen-Qi; Sun, Dong-Mei; Xu, Lin; Tang, Ya-Wen

    2016-01-01

    Elaborate architectural manipulation of nanohybrids with multi-components into controllable 3D hierarchical structures is of great significance for both fundamental scientific interest and realization of various functionalities, yet remains a great challenge because different materials with distinct physical/chemical properties could hardly be incorporated simultaneously into the synthesis process. Here, we develop a novel one-pot cyanogel-bridged synthetic approach for the generation of 3D flower-like metal/Prussian blue analogue nanohybrids, namely PdCo/Pd-hexacyanocobaltate for the first time. The judicious introduction of polyethylene glycol (PEG) and the formation of cyanogel are prerequisite for the successful fabrication of such fascinating hierarchical nanostructures. Due to the unique 3D hierarchical structure and the synergistic effect between hybrid components, the as-prepared hybrid nanoflowers exhibit a remarkable catalytic activity and durability toward the reduction of Rhodamine B (RhB) by NaBH4. We expect that the obtained hybrid nanoflowers may hold great promises in water remediation field and beyond. Furthermore, the facile synthetic strategy presented here for synthesizing functional hybrid materials can be extendable for the synthesis of various functional hybrid nanomaterials owing to its versatility and feasibility. PMID:27573057

  11. Platinum-Copper Nanoframes: One-Pot Synthesis and Enhanced Electrocatalytic Activity.

    PubMed

    Yu, Xiaofei; Li, Lanlan; Su, Yanqiu; Jia, Wei; Dong, Lili; Wang, Dingsheng; Zhao, Jianling; Li, Yadong

    2016-03-24

    Platinum-copper nanoframes were produced from copper nanoparticles by a one-pot synthesis method. The growth mechanism was thoroughly studied by experiment and theoretical calculations. Owing to the unique structure, Pt-Cu nanoframes exhibited significantly enhanced catalytic activity toward the electro-oxidation of methanol compared to commercial Pt black. PMID:26880582

  12. One-pot reductive mono-N-alkylation of aniline and nitroarene derivatives using aldehydes.

    PubMed

    Byun, Eunyoung; Hong, Bomi; De Castro, Kathlia A; Lim, Minkyung; Rhee, Hakjune

    2007-12-01

    One-pot reductive mono-N-alkylation of aniline and nitroarene derivatives using various aldehydes by Pd/C catalyst in aqueous 2-propanol solvent with ammonium formate as in situ hydrogen donor is illustrated. The reaction proceeded smoothly and selectively with excellent yield at room temperature. Our protocol presents a facile, economical, and environmentally benign alternative for reductive amination. PMID:17997570

  13. One-pot synthesis, optical property and self-assembly of monodisperse silver nanospheres

    SciTech Connect

    Tang Aiwei; Qu Shengchun; Hou Yanbing; Teng Feng; Wang Yongsheng; Wang Zhanguo

    2011-08-15

    High-quality spherical silver (Ag) nanocrystals have been synthesized by using a one-pot approach, in which pre-synthesis of organometallic precursors is not required. This reaction involves the thermolysis of a mixed solution of silver acetate and n-dodecanethiol in a non-coordinating organic solvent. The size of the as-obtained Ag nanospheres can be controlled by adjusting the reaction time, reaction temperature and the amount of silver acetate added. The growth and nucleation process of the resultant Ag nanospheres have been studied by employing UV-vis absorption spectra and transmission electron microscopy (TEM) images. Furthermore, these Ag nanospheres have good self-assembly behaviors, and they are easily self-assembled into two- or three-dimensional superlattice structures due to the bundling and interdigitation of thiolate molecules adsorbed on Ag nanospheres. This one-pot synthetic procedure is simple and highly reproducible, which may be extended to prepare other noble-metal nanocrystals. - Graphical abstract: Different sized and monodisperse silver nanospheres were prepared using a one-pot approach with no pre-synthesis of organometallic precursors, and the silver nanospheres can self-assemble into highly ordered superlattices. Highlights: > Monodisperse silver nanospheres have been synthesized by a one-pot approach. > The synthetic method does not need pre-synthesis of organometallic precursors. > The silver nanospheres can self-assemble into highly ordered superlattices. > This synthetic method can be extended to prepare other metal nanocrystals.

  14. One-pot construction of multipodal hybrid periodic mesoporous organosilica nanoparticles with crystal-like architectures.

    PubMed

    Croissant, Jonas; Cattoën, Xavier; Wong Chi Man, Michel; Dieudonné, Philippe; Charnay, Clarence; Raehm, Laurence; Durand, Jean-Olivier

    2015-01-01

    The design of hybrid multipodal PMO (mp-PMO) nanoparticles with crystal-like architectures elaborated in a one-pot, two-step process, involving the preparation of a benzene-based spherical PMO core followed by the formation of ethylene-based rod-shaped PMO pods on these cores is described. PMID:25378091

  15. A firefly inspired one-pot chemiluminescence system using n-propylphosphonic anhydride (T3P).

    PubMed

    Kato, Dai-ichiro; Shirakawa, Daiki; Polz, Robin; Maenaka, Mika; Takeo, Masahiro; Negoro, Seiji; Niwa, Kazuki

    2014-12-01

    A simple reaction procedure for chemiluminescence of firefly luciferin (D-luc) using n-propylphosphonic anhydride (T3P) is reported. A luminescent photon is produced as a result of one-pot reaction, only requiring mixing with the substrate carboxylic acid and T3P in the presence of a mild organic base. PMID:25350893

  16. One-Pot Conversion of Carbohydrates into Furan Derivatives via Furfural and 5-Hydroxylmethylfurfural as Intermediates.

    PubMed

    Liu, Bing; Zhang, Zehui

    2016-08-23

    Recently, there has been growing interest in the transformation of renewable biomass into value-added fuels and chemicals. The catalytic conversion of naturally abundant carbohydrates can generate two-important furan chemicals: 5-hydroxymethylfurfural (HMF) from C6 carbohydrates and furfural from C5 carbohydrates. Both HMF and furfural have received great interest as precursors in the synthesis of commodity chemicals and liquid fuels. In recent years, a trend has emerged to integrate sequential catalytic processes involving multistep reactions for the direct one-pot transformation of carbohydrates into the aimed fuels and chemicals. One-pot reactions have remarkably unique and environmentally friendly benefits, including the fact that isolation and purification of intermediate compounds can be avoided. Herein, the present article aims to review recent advances in the one-pot conversion of carbohydrates into furan derivatives via furfural and HMF as intermediates. Special attention will be paid to the catalytic systems, mechanistic insight, reaction pathways, and catalyst stability. It is expected that this review will guide researchers to develop effective catalytic systems for the one-pot transformation of carbohydrates into furan derivatives. PMID:27396713

  17. Organocatalytic One-Pot Asymmetric Synthesis of Thiolated Spiro-γ-lactam Oxindoles Bearing Three Stereocenters.

    PubMed

    Huang, Xin; Liu, Miao; Pham, Kenny; Zhang, Xiaofeng; Yi, Wen-Bin; Jasinski, Jerry P; Zhang, Wei

    2016-07-01

    The first asymmetric synthesis of spiro-γ-lactam oxindoles bearing three stereocenters is reported. One-pot thiol-Michael/Mannich/lactamization reactions promoted by a recyclable fluorous bifunctional cinchona alkaloid/thiourea organocatalyst afford products in moderate to good yields with up to 95% ee and 6:1 dr. PMID:27258150

  18. "One-pot" access to dihydrofurans via tandem oxidative difunctionalization and ring contraction of aminopyrans.

    PubMed

    Mandha, Santhosh Reddy; Alla, Manjula; Nanubolu, Jagadeesh Babu

    2014-07-01

    An operationally simple and efficient protocol for the construction of dihydrofuran derivatives has been accomplished via a sequential addition of N-chlorosuccinimide and a base to 2-amino-4H-pyran derivatives in alcohol medium. The one-pot protocol proceeding via tandem oxidative difunctionalization and ring contraction provides an entirely new strategy for the construction of the dihydrofuran skeleton. PMID:24846686

  19. One-pot sequential asymmetric hydrogenation of β-aryl-β-aryloxy acroleins.

    PubMed

    Liu, Yufeng; Chen, Jianzhong; Zhang, Zhenfeng; Qin, Jian; Zhao, Min; Zhang, Wanbin

    2016-08-01

    A one-pot sequential asymmetric hydrogenation of β-aryl-β-aryloxy acroleins has been realized for the preparation of chiral 3-aryl-3-aryloxy alcohols with excellent yields and good enantioselectivities. This methodology can be employed in new synthetic routes for the synthesis of fluoxetine, atomoxetine, and related analogues. PMID:27439010

  20. Facile one-pot synthesis of unsymmetrical ureas, carbamates, and thiocarbamates from Cbz-protected amines.

    PubMed

    Kim, Hee-Kwon; Lee, Anna

    2016-07-26

    A novel one-pot synthesis of unsymmetrical ureas, carbamates and thiocarbamates from Cbz-protected amines has been developed. In the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, isocyanates are generated in situ, which facilitate rapid reaction with amines, alcohols, and thiols to afford the corresponding ureas, carbamates and thiocarbamates in high yields. PMID:27406041

  1. One-Pot Anti-Markovnikov Hydroamination of Unactivated Alkenes by Hydrozirconation and Amination

    PubMed Central

    Strom, Alexandra E.

    2013-01-01

    A one-pot hydroamination of alkenes is reported. The synthesis of primary and secondary amines from unactivated olefins was accomplished in the presence of a variety of functional groups. Hydrozirconation, followed by amination with nitrogen electrophiles, provides exclusive anti-Markovnikov selectivity, and most products are isolated in high yields without the use of column chromatography. PMID:23899320

  2. An Electron-Poor C64 Nanographene by Palladium-Catalyzed Cascade C-C Bond Formation: One-Pot Synthesis and Single-Crystal Structure Analysis.

    PubMed

    Seifert, Sabine; Shoyama, Kazutaka; Schmidt, David; Würthner, Frank

    2016-05-23

    Herein, we report the one-pot synthesis of an electron-poor nanographene containing dicarboximide groups at the corners. We efficiently combined palladium-catalyzed Suzuki-Miyaura cross-coupling and dehydrohalogenation to synthesize an extended two-dimensional π-scaffold of defined size in a single chemical operation starting from N-(2,6-diisopropylphenyl)-4,5-dibromo-1,8-naphthalimide and a tetrasubstituted pyrene boronic acid ester as readily accessible starting materials. The reaction of these precursors under the conditions commonly used for Suzuki-Miyaura cross-coupling afforded a C64 nanographene through the formation of ten C-C bonds in a one-pot process. Single-crystal X-ray analysis unequivocally confirmed the structure of this unique extended aromatic molecule with a planar geometry. The optical and electrochemical properties of this largest ever synthesized planar electron-poor nanographene skeleton were also analyzed. PMID:27058998

  3. One-pot synthesis of Ag nanoparticle-coated Pb-based glass frit used in crystalline silicon solar cell

    NASA Astrophysics Data System (ADS)

    Zhou, Jian; Gan, Weiping; Tang, Hongbo; Li, Yingfen; Yang, Chao

    2015-03-01

    Deposition of Ag nanoparticles onto the surface of commercial Pb-based glass frit was conducted via a novel and facile one-pot procedure—a modified polyol process. The procedure included two steps: a 5-min pretreatment of the glass frit at 25 °C in a sonication bath and a 1-h electroless plating at 75 °C in a water bath, which only involved AgNO3 and ethylene glycol but without stabilizing agent. The silver-coated glass frit particles were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma emission spectrometer and energy dispersive spectroscopy. It was found that the glass frit particles were homogeneously coated with dense crystalline Ag nanoparticles with an average diameter of 15 nm on the surfaces. Electrical performance of the solar cells was improved after the deposition.

  4. Multicomponent Coupling Cyclization Access to Cinnolines via in Situ Generated Diazene with Arynes, and α-Bromo Ketones.

    PubMed

    Shu, Wen-Ming; Ma, Jun-Rui; Zheng, Kai-Lu; Wu, An-Xin

    2016-01-15

    A transition-metal-free multicomponent coupling cyclization reaction was explored involving arynes, tosylhydrazine, and α-bromo ketones. The reaction proceeds via a formal [2 + 2 + 2] cycloaddition, giving access to cinnoline derivatives in moderate yields under mild conditions. Three chemical bonds were formed-two C-N bonds and one C-C bond-in a single step. PMID:26700265

  5. Closed-System One-Pot Block Copolymerization by Temperature-Modulated Monomer Segregation.

    PubMed

    Carmean, R Nicholas; Figg, C Adrian; Becker, Troy E; Sumerlin, Brent S

    2016-07-18

    A biphasic one-pot polymerization method enables the preparation of block copolymers from monomers with similar and competitive reactivities without the addition of external materials. AB diblock copolymers were prepared by encapsulating a frozen solution of monomer B on the bottom of a reaction vessel, while the solution polymerization of monomer A was conducted in a liquid layer above. Physical separation between the solid and liquid phases permitted only homopolymerization of monomer A until heating above the melting point of the lower phase, which released monomer B, allowing the addition of the second block to occur. The triggered release of monomer B allowed for chain extension without additional deoxygenation steps or exogenous monomer addition. A method for the closed (i.e., without addition of external reagents) one-pot synthesis of block copolymers with conventional glassware using straightforward experimental techniques has thus been developed. PMID:27258702

  6. Nanotexaphyrin: One-Pot Synthesis of a Manganese Texaphyrin-Phospholipid Nanoparticle for Magnetic Resonance Imaging.

    PubMed

    Keca, Joseph M; Chen, Juan; Overchuk, Marta; Muhanna, Nidal; MacLaughlin, Christina M; Jin, Cheng S; Foltz, Warren D; Irish, Jonathan C; Zheng, Gang

    2016-05-17

    The discovery and synthesis of novel multifunctional organic building blocks for nanoparticles is challenging. Texaphyrin macrocycles are capable and multifunctional chelators. However, they remain elusive as building blocks for nanoparticles because of the difficulty associated with synthesis of texaphyrin constructs capable of self-assembly. A novel manganese (Mn)-texaphyrin-phospholipid building block is described, along with its one-pot synthesis and self-assembly into a Mn-nanotexaphyrin. This nanoparticle possesses strong resilience to manganese dissociation, structural stability, in vivo bio-safety, and structure-dependent T1 and T2 relaxivities. Magnetic resonance imaging (MRI) contrast enhanced visualization of lymphatic drainage is demonstrated with respect to proximal lymph nodes on the head and neck VX-2 tumors of a rabbit. Synthesis of 17 additional metallo-texaphyrin building blocks suggests that this novel one-pot synthetic procedure for nanotexaphyrins may lead to a wide range of applications in the field of nanomedicines. PMID:27071806

  7. One-pot synthesis of one-dimensional CdTe-cystine nanocomposite for humidity sensing

    NASA Astrophysics Data System (ADS)

    Lu, Zhisong; Wang, Jing; Xie, Jiale; Li, Chang Ming

    2014-03-01

    Quantum dot (QD)-incorporated one-dimensional (1D) nanocomposites offer great application potential. However, a facile one-step synthesis of the nanocomposites and fabrication of their free-standing film for sensing has not been accomplished. Herein a rod-shaped nanocomposite is one-pot synthesized via an L-cysteine-assisted hydrothermal approach, in which synthesis parameters including L-cysteine amount, temperature and reaction duration are tailored to control the composite nanostructures. CdTe nanocrystals are incorporated into the L-cystine matrices to form the nanorods, which tangle each other to network an intact film structure via a simple drying process. The free-standing CdTe-cystine nanorod film is directly utilized as a humidity sensor. This work provides a one-pot synthesis approach to grow 1D CdTe incorporated nanocomposites, demonstrating their great potential in film sensing applications.

  8. One-pot synthesis of functionalized germanium nanocrystals from a single source precursor

    NASA Astrophysics Data System (ADS)

    Purkait, Tapas K.; Swarnakar, Anindya K.; de Los Reyes, Glenda B.; Hegmann, Frank A.; Rivard, Eric; Veinot, Jonathan G. C.

    2015-01-01

    One-pot syntheses of surface functionalized germanium nanocrystals (GeNCs) based upon traditional hot injection and microwave-assisted heating of a Ge(ii) dihydride single source precursor have been developed. The reported procedures offer in situ hydrogermylation-based covalent attachment of alkene/alkyne derived surface moieties that give access to hydrophobic or hydrophilic GeNCs.One-pot syntheses of surface functionalized germanium nanocrystals (GeNCs) based upon traditional hot injection and microwave-assisted heating of a Ge(ii) dihydride single source precursor have been developed. The reported procedures offer in situ hydrogermylation-based covalent attachment of alkene/alkyne derived surface moieties that give access to hydrophobic or hydrophilic GeNCs. Electronic supplementary information (ESI) available: Experimental details, FTIR, TEM images and XPS of thermally functionalized GeNCs. See DOI: 10.1039/c4nr05125d

  9. One-pot synthesis of thermoplastic mixed paramylon esters using trifluoroacetic anhydride.

    PubMed

    Shibakami, Motonari; Tsubouchi, Gen; Sohma, Mitsugu; Hayashi, Masahiro

    2015-03-30

    Mixed paramylon esters prepared from paramylon (a storage polysaccharide of Euglena), acetic acid, and a long-chain fatty acid by one-pot synthesis using trifluoroacetic anhydride as a promoter and solvent were shown to have thermoplasticity. Size exclusion chromatography indicated that the mixed paramylon esters had a weight average molecular weight of approximately 4.9-6.7×10(5). Thermal analysis showed that these esters were stable in terms of the glass transition temperature (>90°C) and 5% weight loss temperature (>320°C). The degree of substitution of the long alkyl chain group, a dominant factor determining thermoplasticity, was controlled by tuning the feed molar ratio of acetic acid and long-chain fatty acid to paramylon. These results implied that the one-pot synthesis is useful for preparing structurally-well defined thermoplastic mixed paramylon esters with high molecular weight. PMID:25563938

  10. Unexpected one-pot synthesis of highly conjugated pentacyclic diquinoid compounds.

    PubMed

    Coletti, Alessia; Lentini, Sara; Conte, Valeria; Floris, Barbara; Bortolini, Olga; Sforza, Fabio; Grepioni, Fabrizia; Galloni, Pierluca

    2012-08-17

    A new class of pentacyclic diquinoid compounds has been synthesized with a facile one-pot reaction of two molecules of 2-hydroxynaphthoquinone and 1-bromoalkanes in the presence of ferrocene. These molecules were isolated as enol tautomers that exhibit intramolecular hydrogen bond and extended electronic conjugation as proved by the intense absorption spectrum with a broad band between 400 and 600 nm. The spectroscopic and electrochemical characterization of this new class of compounds has been performed. One of the synthesized diquinoid derivatives showed a significant cytotoxicity with IC(50) values of 25-50 μM against Cisplatin-Resistant SKOV3 and colon carcinoma SW480 cell lines. The results of our study provide a valuable tool to a one-pot synthesis of highly conjugated polyquinones, analogous to important biological systems, with significant antitumoral activity. PMID:22834705

  11. Copper-catalyzed one-pot trifluoromethylation/aryl migration/carbonyl formation with homopropargylic alcohols.

    PubMed

    Gao, Pin; Shen, Yong-Wen; Fang, Ran; Hao, Xin-Hua; Qiu, Zi-Hang; Yang, Fan; Yan, Xiao-Biao; Wang, Qiang; Gong, Xiang-Jun; Liu, Xue-Yuan; Liang, Yong-Min

    2014-07-14

    A novel copper-catalyzed one-pot functionalization of homopropargylic alcohols that involves trifluoromethylation, aryl migration, and formation of a carbonyl moiety has been developed. This reaction constitutes the first direct conversion of homopropargylic alcohols into CF3-containing 3-butenal or 3-buten-1-one derivatives in a regioselective manner. Mechanistic studies indicate that the 1,4-aryl migration proceeds through a radical pathway. PMID:24938432

  12. One-Pot Regiospecific Synthesis of Quinoxalines via a CH2-Extrusion Reaction.

    PubMed

    Shen, Jinhai; Wang, Xiangdong; Lin, Xing; Yang, Zhenhui; Cheng, Guolin; Cui, Xiuling

    2016-03-18

    A convenient "one-pot" regiospecific synthesis of substituted quinoxalines from o-phenylenediamines and ynones under metal-free conditions has been developed. An intermolecular Michael addition reaction, a dehydration condensation, and a base-promoted C-α-CH2-extrusion were involved in this procedure, which features high regioselectivity, efficiency, and environmental friendliness. Various quinoxalines were provided in up to 95% yield for 33 examples. PMID:26925522

  13. A one-pot synthesis of α-l-threofuranosyl nucleoside triphosphates (tNTPs).

    PubMed

    Sau, Sujay P; Chaput, John C

    2016-07-15

    TNA (α-l-threofuranosyl nucleoside) triphosphates of adenosine (tATP), guanosine (tGTP), cytidine (tCTP), and thymidine (tTTP) were synthesized from their corresponding 3'-O-phosphoramidite derivatives using a novel one-pot reaction that is less moisture sensitive than traditional methods. The chemically synthesized tNTPs, despite containing an unnatural 3'-triphosphate moiety, are similar in thermal stability to natural nucleotide triphosphates. PMID:27246616

  14. One-Pot Copper(I)-Catalyzed Ligand/Base-Free Tandem Cyclooxidative Synthesis of Quinazolinones.

    PubMed

    Upadhyaya, Kapil; Thakur, Ravi Kumar; Shukla, Sanjeev K; Tripathi, Rama Pati

    2016-06-17

    A novel and efficient Cu(I)-catalyzed ligand- and base-free multipathway domino strategy has been developed for the synthesis of 2-substituted quinazolinones. The reaction utilizes 2-bromobenzamide and multiform substrates such as aldehydes, alcohols, and methyl arenes for a one-pot protocol, whereas TMSN3 is used as a nitrogen source. A wide range of substrate scope, functional group tolerance, and operational simplicity are synthetically useful features. PMID:27223462

  15. Ir-Cu nanoframes: one-pot synthesis and efficient electrocatalysts for oxygen evolution reaction.

    PubMed

    Pei, Jiajing; Mao, Junjie; Liang, Xin; Chen, Chen; Peng, Qing; Wang, Dingsheng; Li, Yadong

    2016-03-01

    Herein, we achieved successful synthesis of uniform Ir-Cu nanoframes with highly open structures by a facile one-pot strategy. The key to obtain alloy nanoframes was the careful control over the reduction and galvanic replacement reactions between different metals. The as-prepared Ir-Cu was proved to be an effective template for constructing trimetallic nanoframes. Furthermore, these highly open nanostructures exhibited excellent electrocatalytic performance toward oxygen evolution reaction in alkaline media. PMID:26864283

  16. Silica: An efficient catalyst for one-pot regioselective synthesis of dithioethers

    PubMed Central

    Kundu, Samir; Roy, Babli

    2014-01-01

    Summary The development of a silica-promoted highly selective synthesis of 1,2 or 1,3-dithioethers via solvent-free one-pot tandem reactions of an allyl bromide with excess thiol at room temperature is described. The choice of silica gel, either pre-calcined or moistened with water, exhibited notable regioselectivity in the formation of dithioethers. Plausible mechanistic routes were explored and postulated. PMID:24454561

  17. Facile one-pot synthesis of porphyrin based porous polymer networks (PPNs) as biomimetic catalysts

    SciTech Connect

    Zou, LF; Feng, DW; Liu, TF; Chen, YP; Fordham, S; Yuan, S; Tian, J; Zhou, HC

    2015-01-01

    Stable porphyrin based porous polymer networks, PPN-23 and PPN-24, have been synthesized through a facile one-pot approach by the aromatic substitution reactions of pyrrole and aldehydes. PPN-24(Fe) shows high catalytic efficiency as a biomimetic catalyst in the oxidation reaction of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) in the presence of H2O2.

  18. One-Pot Synthesis of Substituted Trifluoromethylated 2,3-Dihydro-1H-imidazoles.

    PubMed

    Deutsch, Amrei; Jessen, Christoph; Deutsch, Carl; Karaghiosoff, Konstantin; Hoffmann-Röder, Anja

    2016-07-15

    An operationally simple one-pot reaction for the preparation of a novel class of racemic trifluoromethylated 2,3-dihydro-1H-imidazoles derived from electron-poor N,O-acetals and aryl Grignard reagents is described. In addition, access to highly functionalized 2-trifluoromethyl-2,3-dihydro-1H-imidazoles was accomplished by reaction of N-aryl hemiaminal ethers and N-aryl trifluoroethylamines in the presence of an excess of n-butyllithium. PMID:27359260

  19. Highly efficient one-pot multienzyme (OPME) synthesis of glycans with fluorous-tag assisted purification.

    PubMed

    Hwang, Joel; Yu, Hai; Malekan, Hamed; Sugiarto, Go; Li, Yanhong; Qu, Jingyao; Nguyen, Van; Wu, Dongyuan; Chen, Xi

    2014-03-25

    Oligo(ethylene glycol)-linked light fluorous tags have been found to be optimal for conjugating to glycans for both high-yield enzymatic glycosylation reactions using one-pot multienzyme (OPME) systems and quick product purification using fluorous solid-phase extraction (FSPE) cartridges. The combination of OPME glycosylation systems and the FSPE cartridge purification scheme provides a highly effective strategy for facile synthesis and purification of glycans. PMID:24473465

  20. One-pot gold-catalyzed synthesis of 3-silylethynyl indoles from unprotected o-alkynylanilines

    PubMed Central

    Brand, Jonathan P; Chevalley, Clara

    2011-01-01

    Summary The Au(III)-catalyzed cyclization of 2-alkynylanilines was combined in a one-pot procedure with the Au(I)-catalyzed C3-selective direct alkynylation of indoles using the benziodoxolone reagent TIPS-EBX to give a mild, easy and straightforward entry to 2-substituted-3-alkynylindoles. The reaction can be applied to unprotected anilines, was tolerant to functional groups and easy to carry out (RT, and requires neither an inert atmosphere nor special solvents). PMID:21647264

  1. Palladium-Catalyzed One-Pot Approach to 3-(Diarylmethylene)oxindoles from Propiolamidoaryl Triflate.

    PubMed

    Lee, Dahye; Park, Sunhwa; Yu, Yoseb; Shin, Kye Jung; Seo, Jae Hong

    2015-01-01

    3-(Diarylmethylene)oxindoles have been synthesized from propiolamidoaryl triflate utilizing a palladium-catalyzed one-pot reaction consisting of three successive reactions: Sonogashira, Heck, and Suzuki-Miyaura. This method allows for the production of a complex skeleton of 3-(diarylmethylene)oxindole from propiolamidoaryl triflate using a commercially available aryl iodide and arylboronic acid in a simple and efficient way with moderate yield and stereoselectivity. PMID:26247925

  2. One-Pot Synthesis of β,β-Disubstituted α,β-Unsaturated Carbonyl Compounds.

    PubMed

    Sugiura, Masaharu; Ashikari, Yasuhiko; Nakajima, Makoto

    2015-09-01

    TiCl4-promoted aldol reaction of ketones as aldol acceptors followed by elimination of the titanoxy group from the Ti-aldolates affords β,β-disubstituted α,β-unsaturated carbonyl compounds in a one-pot procedure. The use of additives, such as DMF, N,N,N',N'-tetramethylethylenediamine, and pyridine, in the elimination step was found to be important. PMID:26284292

  3. One-pot, two-step desymmetrization of symmetrical benzils catalyzed by the methylsulfinyl (dimsyl) anion.

    PubMed

    Ragno, Daniele; Bortolini, Olga; Giovannini, Pier Paolo; Massi, Alessandro; Pacifico, Salvatore; Zaghi, Anna

    2014-08-14

    An operationally simple one-pot, two-step procedure for the desymmetrization of benzils is herein described. This consists in the chemoselective cross-benzoin reaction of symmetrical benzils with aromatic aldehydes catalyzed by the methyl sulfinyl (dimsyl) anion, followed by microwave-assisted oxidation of the resulting benzoylated benzoins with nitrate, avoiding the costly isolation procedure. Both electron-withdrawing and electron-donating substituents may be accommodated on the aromatic rings of the final unsymmetrical benzil. PMID:24967946

  4. One-pot enzymatic conversion of carbon dioxide and utilization for improved microbial growth.

    PubMed

    Hong, Sung-Gil; Jeon, Hancheol; Kim, Han Sol; Jun, Seung-Hyun; Jin, EonSeon; Kim, Jungbae

    2015-04-01

    We developed a process for one-pot CO2 conversion and utilization based on simple conversion of CO2 to bicarbonate at ambient temperature with no energy input, by using the cross-linking-based composites of carboxylated polyaniline nanofibers (cPANFs) and carbonic anhydrase. Carbonic anhydrase was immobilized on cPANFs via the approach of magnetically separable enzyme precipitate coatings (Mag-EPC), which consists of covalent enzyme attachment, enzyme precipitation, and cross-linking with amine-functionalized magnetic nanoparticles. Mag-EPC showed a half-life of 236 days under shaking, even resistance to 70% ethanol sterilization, and recyclability via facile magnetic separation. For one-pot CO2 conversion and utilization, Mag-EPC was used to accelerate the growth of microalga by supplying bicarbonate from CO2, representing 1.8-fold increase of cell concentration when compared to the control sample. After two repeated uses via simple magnetic separation, the cell concentration with Mag-EPC was maintained as high as the first cycle. This one-pot CO2 conversion and utilization is an alternative as well as complementary process to adsorption-based CO2 capture and storage as an environmentally friendly approach, demanding no energy input based on the effective action of the stabilized enzyme system. PMID:25815899

  5. One-Pot Synthesis of (NiFe2O4)x-(SrFe12O19)1-x Nanocomposites and Their Microwave Absorption Properties.

    PubMed

    Hazra, Subhenjit; Ghosh, Barun Kumar; Patra, Manoj Kumar; Jani, Raj Kumar; Vadera, Sampat Raj; Ghosh, Narendra Nath

    2015-09-01

    In this paper, we report a simple but novel aqueous solution based 'one-pot' method for preparation of (NiFe2O4)x-(SrFe12O19)1-x nanocomposites consist of hard ferrite-soft ferrite phases. A physical mixing method has also been employed to prepare nanocomposites having same compositions. The effects of synthetic methodologies on the microstructures of the nanocomposites as well as their magnetic and microwave absorption properties have been evaluated. Crystal structures and microstructures of these composites have been investigated by using X-ray diffraction, transmission electron microscope and scanning electron microscope. In the nanocomposites, prepared by both methods, presence of nanocrystalline NiFe2O4 and SrFe12O19 phases was detected. However, nanocomposites, prepared by one-pot method, possessed better homogeneous distribution of hard and soft ferrite phases than the nanocomposites, prepared by physical mixing method. Nanocomposites, prepared by one-pot method, demonstrated significant spring exchange coupling interaction between hard and soft ferrite phases and exhibited magnetically single phase behaviour. The spring exchange coupling interaction enhanced the magnetic properties (high saturation magnetization and coercivity) and microwave absorption properties of the nanocomposites, prepared by one-pot method, in comparison with the nanocomposites prepared by physical mixing method as well as pure NiFe2O4 and SrFe12O19 nanoparticles. Minimum reflection loss of the composite was ~ -17 dB (i.e., 98% absorption) at 8.2 GHz for an absorber thickness of 3.2 mm. PMID:26716212

  6. Covalent Modification of Organo-Functionalized Graphene Oxide and its Scope as Catalyst for One-Pot Pyrazolo-Pyranopyrimidine Derivatives.

    PubMed

    Rana, Surjyakanta; Maddila, Suresh; Yalagala, Kotaiah; Maddila, Suryanarayana; Jonnalagadda, Sreekantha B

    2015-12-01

    The surface of graphene oxide (GO) was modified using [3-(2-aminoethylamino)propyl]trimethoxysilane (diamine), which exhibited excellent catalytic activity for one-pot multicomponent reactions. The newly synthesized material was fully characterized by various instrumental techniques including Fourier-transfer infrared (FTIR) and Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The instrumental analysis confirmed the successful grafting of organic amine functional groups onto the graphene oxide surface. The diamine-functionalized GO proved to be an excellent catalyst for the synthesis of pyrazolo-pyranopyrimidine derivatives with 93 % yield and high selectivity. The catalytic activity almost remained unaltered up to three cycles. The newly synthesized pyrazolo-pyranopyrimidine derivatives have potential use as scaffolds in designing new pharmaceutical products. PMID:27308195

  7. Synthesis of Diverse Nitrogen-Enriched Heterocyclic Scaffolds Using a Suite of Tunable One-Pot Multicomponent Reactions

    PubMed Central

    2015-01-01

    Five elegant and switchable three-component reactions which enable access to a new series of nitrogen-containing heterocycles are reported. A novel one-step addition of an isocyanide to a hydrazine derived Schiff base affords unique six-membered pyridotriazine scaffolds (A and E). With slight modification of reaction conditions and replacement of the nucleophilic isocyanide moiety with different electrophiles (i.e., isocyanates, isothiocyanates, cyclic anhydrides, and acyl chlorides) five-membered triazolopyridine scaffolds (B, D, F, G) are generated in a single step. Furthermore, the use of phenyl hydrazine enables access to dihydroindazole-carboxamides, devoid of a bridge-head nitrogen (C). All protocols are robust and tolerate a diverse collection of reactants, and as such, it is expected that the new scaffolds and associated chemistry will garner high interest from medicinal chemists involved in either file enhancement or specific target-related drug discovery campaigns. PMID:24788091

  8. Enzymatic Menthol Production: One-Pot Approach Using Engineered Escherichia coli.

    PubMed

    Toogood, Helen S; Ní Cheallaigh, Aisling; Tait, Shirley; Mansell, David J; Jervis, Adrian; Lygidakis, Antonios; Humphreys, Luke; Takano, Eriko; Gardiner, John M; Scrutton, Nigel S

    2015-10-16

    Menthol isomers are high-value monoterpenoid commodity chemicals, produced naturally by mint plants, Mentha spp. Alternative clean biosynthetic routes to these compounds are commercially attractive. Optimization strategies for biocatalytic terpenoid production are mainly focused on metabolic engineering of the biosynthesis pathway within an expression host. We circumvent this bottleneck by combining pathway assembly techniques with classical biocatalysis methods to engineer and optimize cell-free one-pot biotransformation systems and apply this strategy to the mint biosynthesis pathway. Our approach allows optimization of each pathway enzyme and avoidance of monoterpenoid toxicity issues to the host cell. We have developed a one-pot (bio)synthesis of (1R,2S,5R)-(-)-menthol and (1S,2S,5R)-(+)-neomenthol from pulegone, using recombinant Escherichia coli extracts containing the biosynthetic genes for an "ene"-reductase (NtDBR from Nicotiana tabacum) and two menthone dehydrogenases (MMR and MNMR from Mentha piperita). Our modular engineering strategy allowed each step to be optimized to improve the final production level. Moderate to highly pure menthol (79.1%) and neomenthol (89.9%) were obtained when E. coli strains coexpressed NtDBR with only MMR or MNMR, respectively. This one-pot biocatalytic method allows easier optimization of each enzymatic step and easier modular combination of reactions to ultimately generate libraries of pure compounds for use in high-throughput screening. It will be, therefore, a valuable addition to the arsenal of biocatalysis strategies, especially when applied for (semi)-toxic chemical compounds. PMID:26017480

  9. One-pot reaction to synthesize PEG-coated hollow magnetite nanostructures with excellent magnetic properties.

    PubMed

    Gao, Qian; Zhang, Jilin; Hong, Guangyan; Ni, Jiazuan

    2010-10-01

    We first demonstrate a simple "one-pot" method to synthesis uniform Fe3O4 hollow microspheres in the presence of PEG in ethylene glycol by using urea to control their morphologies. The interior cavity of the hollow spheres can be tunable by reaction time. The Lamer model was used to explain the formation of magnetite hollow spherical structures based on the experimental observations. The obtained hollow Fe3O4 microspheres showing superparamagnetism with a high saturation magnetization of ca. 86.4 emu/g, and also had an enrichment surface of -OH groups, which will be favorable to the further modification with other biomedical molecules. PMID:21137737

  10. One-pot and two-step synthesis of novel carbonylthioureas and dicarbonyldithioureas derivatives

    NASA Astrophysics Data System (ADS)

    Banaei, Alireza; Shiran, Jafar Abbasi; Saadat, Afshin; Ardabili, Farnaz Fazlalizadeh; McArdle, Patrick

    2015-11-01

    One-pot, two-step synthesis of several 1-cyclopropanecarbonyl-3-(substituted phenyl)-thioureas and 1-(phenylene-1,4-dione)-3,3‧-(substituted phenyl)-dithioureas have been successfully prepared. The structures of the synthesized compounds were confirmed by elemental analysis, FT-IR spectroscopy and NMR. Also the crystal structure one of these compounds was determined by X-ray crystallography. All synthesized compounds were evaluated for antibacterial activity using Salmonella enterica (SE), Micrococcus luteus (ML), Bacillus subtilis (BS) and Pseudomonas aeruginosa (PS).

  11. One-pot synthesis of hematite@graphene core@shell nanostructures for superior lithium storage

    NASA Astrophysics Data System (ADS)

    Chen, Dezhi; Quan, Hongying; Liang, Junfei; Guo, Lin

    2013-09-01

    Novel hematite@graphene composites have been successfully synthesized by a one-pot surfactant governed approach under mild wet-chemical conditions. A series of characterizations including X-ray diffraction (XRD), Raman spectrum, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that the hematite nanoparticles with relatively uniform size were encapsulated by graphene layers and were able to form core-shell nanostructures. The electrochemical properties of hematite@graphene core-shell nanostructures as anodes for lithium-ion batteries were evaluated by galvanostatic charge-discharge and AC impedance spectroscopy techniques. The as-prepared hematite@graphene core-shell nanostructures exhibited a high reversible specific capacity of 1040 mA h g-1 at a current density of 200 mA g-1 (0.2 C) after 180 cycles and excellent rate capability and long cycle life. Furthermore, a reversible capacity as high as 500 mA h g-1 was still achieved after 200 cycles even at a high rate of 6 C. The electrochemical test results show that the hematite@graphene composites prepared by the one-pot wet chemical method are promising anode materials for lithium-ion batteries.Novel hematite@graphene composites have been successfully synthesized by a one-pot surfactant governed approach under mild wet-chemical conditions. A series of characterizations including X-ray diffraction (XRD), Raman spectrum, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that the hematite nanoparticles with relatively uniform size were encapsulated by graphene layers and were able to form core-shell nanostructures. The electrochemical properties of hematite@graphene core-shell nanostructures as anodes for lithium-ion batteries were evaluated by galvanostatic charge-discharge and AC impedance spectroscopy techniques. The as-prepared hematite@graphene core-shell nanostructures exhibited a high reversible specific capacity of 1040 mA h g-1 at a

  12. One-Pot Exfoliation of Graphite and Synthesis of Nanographene/Dimesitylporphyrin Hybrids

    PubMed Central

    Bernal, M. Mar; Pérez, Emilio M.

    2015-01-01

    A simple one-pot process to exfoliate graphite and synthesize nanographene-dimesitylporphyrin hybrids has been developed. Despite the bulky mesityl groups, which are expected to hinder the efficient π–π stacking between the porphyrin core and graphene, the liquid-phase exfoliation of graphite is significantly favored by the presence of the porphyrins. Metallation of the porphyrin further enhances this effect. The resulting graphene/porphyrin hybrids were characterized by spectroscopy (UV-visible, fluorescence, and Raman) and microscopy (STEM, scanning transmission electron microscopy). PMID:25984598

  13. One-pot palladium-catalyzed borrowing hydrogen synthesis of thioethers.

    PubMed

    Corma, Avelino; Navas, Javier; Ródenas, Tania; Sabater, María J

    2013-12-16

    Palladium on magnesium oxide is able to allow a one-pot reaction to synthesize thioethers from thiols and aldehydes formed in situ from the respective alcohol by means of a borrowing hydrogen method. The reaction is initiated by dehydrogenation of the alcohol to give a palladium hydride intermediate and an aldehyde. The latter reacts with a thiol involving most probably the intermediacy of a thionium ion RCH=S(+)R, which can be reduced in situ by the metal hydride to afford thioethers. PMID:24259460

  14. One-Pot Synthesis of β-Acetamido Ketones Using Boric Acid at Room Temperature

    PubMed Central

    Karimi-Jaberi, Zahed; Mohammadi, Korosh

    2012-01-01

    β-acetamido ketones were synthesized in excellent yields through one-pot condensation reaction of aldehydes, acetophenones, acetyl chloride, and acetonitrile in the presence of boric acid as a solid heterogeneous catalyst at room temperature. It is the first successful report of boric acid that has been used as solid acid catalyst for the preparation of β-acetamido ketones. The remarkable advantages offered by this method are green catalyst, mild reaction conditions, simple procedure, short reaction times, and good-to-excellent yields of products. PMID:22666168

  15. 'Super Silyl' Group for Diastereoselective Sequential Reactions: Access to Complex Chiral Architecture in One Pot

    SciTech Connect

    Boxer, Matthew B.; Yamamoto, Hisashi

    2008-04-02

    We have shown that the tris(trimethylsilyl)silyl (TTMSS) silyl enol ether of acetaldehyde undergoes aldehyde cross-aldol reactions with high selectivity and the extremely low catalyst loading (0.05 mol % of HNTf{sub 2}) allows for one-pot sequential reactions where acidic or basic nucleophiles can be subsequently added. Various ketone-derived silyl enol ethers, Grignard reagents, and dienes succeeded, generating relatively complex molecular architectures in a single step. This represents the first case where, in a single pot, highly acidic conditions followed by very basic conditions were tolerated to give products with high diastereoselectivities and good yields.

  16. An Efficient Protection-Free One-Pot Chemical Synthesis of Modified Nucleoside-5'-Triphosphates.

    PubMed

    Shanmugasundaram, Muthian; Senthilvelan, Annamalai; Xiao, Zejun; Kore, Anilkumar R

    2016-07-01

    A simple, reliable, and an efficient "one-pot, three step" chemical method for the synthesis of modified nucleoside triphosphates such as 5-methylcytidine-5'-triphosphate (5-MeCTP), pseudouridine-5'-triphosphate (pseudoUTP) and N(1)-methylpseudouridine-5'-triphosphate (N(1)-methylpseudoUTP) starting from the corresponding nucleoside is described. The overall reaction involves the monophosphorylation of nucleoside, followed by the reaction with pyrophosphate and subsequent hydrolysis of the cyclic intermediate to furnish the corresponding NTP in moderate yields with high purity (>99.5%). PMID:27159048

  17. One-Pot, Four-Step Organocatalytic Asymmetric Synthesis of Functionalized Nitrocyclopropanes.

    PubMed

    Zaghi, Anna; Bernardi, Tatiana; Bertolasi, Valerio; Bortolini, Olga; Massi, Alessandro; De Risi, Carmela

    2015-09-18

    The asymmetric synthesis of functionalized nitrocyclopropanes has been achieved by a one-pot, four-step method catalyzed by (S)-diphenylprolinol TMS ether, which joins two sequential domino reactions, namely a domino sulfa-Michael/aldol condensation of α,β-unsaturated aldehydes with 1,4-dithiane-2,5-diol, and a domino Michael/α-alkylation reaction of the derived chiral dihydrothiophenes with bromonitromethane. The title compounds were obtained in 27-45% yields, with high levels of diastereoselectivity (93:7 to 100:0 dr) and generally good enantioselectivities (up to 95:5 er). PMID:26317611

  18. Multicomponent diffusion in ternary and quaternary diffusion couples and in multilayered assemblies

    NASA Astrophysics Data System (ADS)

    Kulkarni, Kaustubh Narhar

    to be one order of magnitude larger than that of Ni. Analytical expressions were developed for spatial and temporal evolution of concentration profiles in single-phase multicomponent multilayered diffusion assemblies (MDAs) assembled with a number of finite alloy-layers of various compositions sandwiched between two bulk terminal alloys. The expressions were successfully used for the prediction of concentration profiles in an experimental Cu-Ni-Zn MDA assembled with a single sandwiched layer and annealed at 775°C. The analytical expressions were also used to simulate evolution of concentration profiles and diffusion paths for a ternary MDA containing a single finite middle layer as a function of layer thickness (h) and time (t). The diffusion path of such an MDA varies with time and each path configuration is associated with a unique h/ t ratio. Diffusional interactions among components may lead to either depletion or accumulation of individual components in the middle layer of an MDA. The MultiDiflux program was also employed for the determination of ternary interdiffusion coefficients for the (beta) Ni-Ru-Al alloys from diffusion couple assembled with NiAl and RuAl disks and annealed at 1100°C.

  19. Precise Tuning of Facile One-Pot Gelatin Methacryloyl (GelMA) Synthesis

    NASA Astrophysics Data System (ADS)

    Shirahama, Hitomi; Lee, Bae Hoon; Tan, Lay Poh; Cho, Nam-Joon

    2016-08-01

    Gelatin-methacryloyl (GelMA) is one of the most commonly used photopolymerizable biomaterials in bio-applications. However, GelMA synthesis remains suboptimal, as its reaction parameters have not been fully investigated. The goal of this study is to establish an optimal route for effective and controllable GelMA synthesis by systematically examining reaction parameters including carbonate-bicarbonate (CB) buffer molarity, initial pH adjustment, MAA concentration, gelatin concentration, reaction temperature, and reaction time. We employed several analytical techniques in order to determine the degree of substitution (DS) and conducted detailed structural analysis of the synthesized polymer. The results enabled us to optimize GelMA synthesis, showing the optimal conditions to balance the deprotonation of amino groups with minimizing MAA hydrolysis, which led to nearly complete substitution. The optimized conditions (low feed ratio of MAA to gelatin (0.1 mL/g), 0.25 M CB buffer at pH 9, and a gelatin concentration of 10–20%) enable a simplified reaction scheme that produces GelMA with high substitution with just one-step addition of MAA in one pot. Looking forward, these optimal conditions not only enable facile one-pot GelMA synthesis but can also guide researchers to explore the efficient, high methacrylation of other biomacromolecules.

  20. Compartmentalization of incompatible reagents within Pickering emulsion droplets for one-pot cascade reactions.

    PubMed

    Yang, Hengquan; Fu, Luman; Wei, Lijuan; Liang, Jifen; Binks, Bernard P

    2015-01-28

    It is a dream that future synthetic chemistry can mimic living systems to process multistep cascade reactions in a one-pot fashion. One of the key challenges is the mutual destruction of incompatible or opposing reagents, for example, acid and base, oxidants and reductants. A conceptually novel strategy is developed here to address this challenge. This strategy is based on a layered Pickering emulsion system, which is obtained through lamination of Pickering emulsions. In this working Pickering emulsion, the dispersed phase can separately compartmentalize the incompatible reagents to avoid their mutual destruction, while the continuous phase allows other reagent molecules to diffuse freely to access the compartmentalized reagents for chemical reactions. The compartmentalization effects and molecular transport ability of the Pickering emulsion were investigated. The deacetalization-reduction, deacetalization-Knoevenagel, deacetalization-Henry and diazotization-iodization cascade reactions demonstrate well the versatility and flexibility of our strategy in processing the one-pot cascade reactions involving mutually destructive reagents. PMID:25603470

  1. One-pot multienzyme (OPME) systems for chemoenzymatic synthesis of carbohydrates.

    PubMed

    Yu, Hai; Chen, Xi

    2016-03-01

    Glycosyltransferase-catalyzed enzymatic and chemoenzymatic syntheses are powerful approaches for the production of oligosaccharides, polysaccharides, glycoconjugates, and their derivatives. Enzymes involved in the biosynthesis of sugar nucleotide donors can be combined with glycosyltransferases in one pot for efficient production of the target glycans from simple monosaccharides and acceptors. The identification of enzymes involved in the salvage pathway of sugar nucleotide generation has greatly facilitated the development of simplified and efficient one-pot multienzyme (OPME) systems for synthesizing major glycan epitopes in mammalian glycomes. The applications of OPME methods are steadily gaining popularity mainly due to the increasing availability of wild-type and engineered enzymes. Substrate promiscuity of these enzymes and their mutants allows OPME synthesis of carbohydrates with naturally occurring post-glycosylational modifications (PGMs) and their non-natural derivatives using modified monosaccharides as precursors. The OPME systems can be applied in sequence for synthesizing complex carbohydrates. The sequence of the sequential OPME processes, the glycosyltransferase used, and the substrate specificities of the glycosyltransferases define the structures of the products. The OPME and sequential OPME strategies can be extended to diverse glycans in other glycomes when suitable enzymes with substrate promiscuity become available. This Perspective summarizes the work of the authors and collaborators on the development of glycosyltransferase-based OPME systems for carbohydrate synthesis. Future directions are also discussed. PMID:26881499

  2. One-pot multienzyme synthesis of Lewis x and sialyl Lewis x antigens

    PubMed Central

    Yu, Hai; Lau, Kam; Li, Yanhong; Sugiarto, Go; Chen, Xi

    2012-01-01

    L-Fucose has been found abundantly in human milk oligosaccharides, bacterial lipopolysaccharides, glycolipids, and many N- and O-linked glycans produced by mammalian cells. Fucose-containing carbohydrates have important biological functions. Alterations in the expression of fucosylated oligosaccharides have been observed in several pathological processes such as cancer and atherosclerosis. Chemical formation of fucosidic bonds is challenging due to its acid lability. Enzymatic construction of fucosidic bonds by fucosyltransferases is highly efficient and selective but requires the expensive sugar nucleotide donor guanosine 5′- diphosphate-L-fucose (GDP-Fuc). Here, we describe a protocol for applying a one-pot three-enzyme system in synthesizing structurally defined fucose-containing oligosaccharides from free L-fucose. In this system, GDP-Fuc is generated from L-fucose, adenosine 5′-triphosphate (ATP), and guanosine 5′-triphosphate (GTP) by a bifunctional L-fucokinase/GDP-fucose pyrophosphorylase (FKP). An inorganic pyrophosphatase (PpA) is used to degrade the by-product pyrophosphate (PPi) to drive the reaction towards the formation of GDP-Fuc. In situ generated GDP-Fuc is then used by a suitable fucosyltransferase for the formation of fucosides. The three-enzyme reactions are carried out in one pot without the need for high cost sugar nucleotide or isolation of intermediates. The time for the synthesis is 4–24 hours. Purification and characterization of products can be completed in 2–3 days. PMID:25000293

  3. Precise Tuning of Facile One-Pot Gelatin Methacryloyl (GelMA) Synthesis

    PubMed Central

    Shirahama, Hitomi; Lee, Bae Hoon; Tan, Lay Poh; Cho, Nam-Joon

    2016-01-01

    Gelatin-methacryloyl (GelMA) is one of the most commonly used photopolymerizable biomaterials in bio-applications. However, GelMA synthesis remains suboptimal, as its reaction parameters have not been fully investigated. The goal of this study is to establish an optimal route for effective and controllable GelMA synthesis by systematically examining reaction parameters including carbonate-bicarbonate (CB) buffer molarity, initial pH adjustment, MAA concentration, gelatin concentration, reaction temperature, and reaction time. We employed several analytical techniques in order to determine the degree of substitution (DS) and conducted detailed structural analysis of the synthesized polymer. The results enabled us to optimize GelMA synthesis, showing the optimal conditions to balance the deprotonation of amino groups with minimizing MAA hydrolysis, which led to nearly complete substitution. The optimized conditions (low feed ratio of MAA to gelatin (0.1 mL/g), 0.25 M CB buffer at pH 9, and a gelatin concentration of 10–20%) enable a simplified reaction scheme that produces GelMA with high substitution with just one-step addition of MAA in one pot. Looking forward, these optimal conditions not only enable facile one-pot GelMA synthesis but can also guide researchers to explore the efficient, high methacrylation of other biomacromolecules. PMID:27503340

  4. D-Fructose-6-phosphate aldolase-catalyzed one-pot synthesis of iminocyclitols.

    PubMed

    Sugiyama, Masakazu; Hong, Zhangyong; Liang, Pi-Hui; Dean, Stephen M; Whalen, Lisa J; Greenberg, William A; Wong, Chi-Huey

    2007-11-28

    A one-pot chemoenzymatic method for the synthesis of a variety of new iminocyclitols from readily available, non-phosphorylated donor substrates has been developed. The method utilizes the recently discovered fructose-6-phosphate aldolase (FSA), which is functionally distinct from known aldolases in its tolerance of different donor substrates as well as acceptor substrates. Kinetic studies were performed with dihydroxyacetone (DHA), the presumed endogenous substrate for FSA, as well as hydroxy acetone (HA) and 1-hydroxy-2-butanone (HB) as donor substrates, in each case using glyceraldehyde-3-phosphate as acceptor substrate. Remarkably, FSA used the three donor substrates with equal efficiency, with kcat/KMvalues of 33, 75, and 20 M-1 s-1, respectively. This level of donor substrate tolerance is unprecedented for an aldolase. Furthermore, DHA, HA, and HB were accepted as donors in FSA-catalyzed aldol reactions with a variety of azido- and Cbz-amino aldehyde acceptors. The broad substrate tolerance of FSA and the ability to circumvent the need for phosphorylated substrates allowed for one-pot synthesis of a number of known and novel iminocyclitols in good yields, and in a very concise fashion. New iminocyclitols were assayed as inhibitors against a panel of glycosidases. Compounds 15 and 16 were specific alpha-mannosidase inhibitors, and 24 and 26 were potent and selective inhibitors of beta-N-acetylglucosaminidases in the submicromolar range. Facile access to these compounds makes them attractive core structures for further inhibitor optimization. PMID:17985886

  5. One-pot, template syntheses of a new class of metallomacrocycles with a tetraoxime cyclic skeleton.

    PubMed

    Tashiro, Shohei; Minoda, Ai; Yamada, Mihoko; Shionoya, Mitsuhiko

    2009-11-01

    Most common macrocycles such as crown ethers, porphyrins, and macrocyclic polyamines show versatile, excellent functions in a variety of research fields such as coordination chemistry, supramolecular chemistry, analytical chemistry, and material sciences. Thus, the rational design of a new class of readily synthesized macrocyclic metal ligands is a key to the development of a new category of functionalized macrocyclic metal complexes. Herein, we report one-pot, template syntheses of a new class of metallomacrocycles with a 16-membered tetraoxime cyclic skeleton from a dioxime in the presence of a template transition-metal ion such as Fe(2+), Ni(2+), Cu(2+), Co(2+), or Ag(+). These metal ions can be easily removed from the mononuclear metallomacrocycles, and, for example, the metal-free tetraoxime ligand was obtained in 90% yield when Fe(2+) was used as the template. It would appear that this one-pot, metal-template cyclization efficiently proceeds through continual metal-mediated oxime exchange reactions. Interestingly, Pd(2+), which does not afford any cyclized products, formed a 1:1 complex with the macrocyclic ligand. The molecular structures of the metal-free ligand, its 1:1 metal complexes with Fe(2+), Ni(2+), Cu(2+), Pd(2+), and Ag(+), and a dinuclear complex with Ag(+) were fully determined by single-crystal X-ray analyses. UV-visible absorption spectra and cyclic voltammetry measurements of these complexes are also reported. PMID:19852519

  6. A one-pot synthetic strategy for construction of the dibenzodiazepine skeleton via a transition metal-free process.

    PubMed

    Fang, Shuai; Niu, Xiaoyi; Zhang, Zeyuan; Sun, Yan; Si, Xiaomeng; Shan, Cuicui; Wei, Lei; Xu, Aiqing; Feng, Lei; Ma, Chen

    2014-09-21

    A one-pot transition metal-free methodology for constructing pharmacologically active dibenzodiazepine derivatives was developed. Fluoro-, bromo- and nitro-substituted aryl aldehydes were applied to this reaction efficiently. PMID:25058616

  7. Modular Synthesis of Novel Macrocycles Bearing α,β-Unsaturated Chemotypes through a Series of One-Pot, Sequential Protocols.

    PubMed

    Javed, Salim; Bodugam, Mahipal; Torres, Jessica; Ganguly, Arghya; Hanson, Paul R

    2016-05-10

    A series of one-pot, sequential protocols was developed for the synthesis of novel macrocycles bearing α,β-unsaturated chemotypes. The method highlights a phosphate tether-mediated approach to establish asymmetry, and consecutive one-pot, sequential processes to access the macrocycles with minimal purification procedures. This library amenable strategy provided diverse macrocycles containing α,β-unsaturated carbon-, sulfur-, or phosphorus-based warheads. PMID:27059428

  8. One-pot versus sequential reactions in the self-assembly of gigantic nanoscale polyoxotungstates.

    PubMed

    Gao, Jing; Yan, Jun; Beeg, Sebastian; Long, De-Liang; Cronin, Leroy

    2013-02-01

    By using a new type of lacunary tungstoselenite {Se(2)W(29)O(103)} (1), which contains a "defect" pentagonal {W(W)(4)} unit, we explored the assembly of clusters using this building block and demonstrate how this unit can give rise to gigantic nanomolecular species, using both a "one-pot" and "stepwise" synthetic assembly approach. Specifically, exploration of the one-pot synthetic parameter space lead to the discovery of {Co(2.5)(W(3.5)O(14))(SeW(9)O(33))(Se(2)W(30)O(107))} (2), {CoWO(H(2)O)(3)(Se(2)W(26)O(85))(Se(3)W(30)O(107))(2)} (3), and {Ni(2)W(2)O(2)Cl(H(2)O)(3)(Se(2)W(29)O(103)) (Se(3)W(30)O(107))(2)} (4), effectively demonstrating the potential of the {Se(2)W(29)} based building blocks, which was further extended by the isolation of a range of 3d transition metal doped tetramer family derivatives: {M(2)W(n)O(m)(H(2)O)(m)(Se(2)W(29)O(102))(4)} (M = Mn, Co, Ni or Zn, n = 2, m = 4; M = Cu, n = 3, m = 5) (5-9). To contrast the 'one-pot' approach, an optimized stepwise self-assembly investigation utilizing 1 as a precursor was performed showing that the high nuclearity clusters can condense in a more controllable way allowing the tetrameric clusters (5-8) to be synthesized with higher yield, but it was also shown that 1 can be used to construct a gigantic {W(174)} hexameric-cluster {Cu(9)Cl(3)(H(2)O)(18)(Se(2)W(29)O(102))(6)} (10). Further, 1 can also dimerize to {(Se(2)W(30)O(105))(2)} (11) by addition of extra tungstate under similar conditions. All the clusters were characterized by single-crystal X-ray crystallography, chemical analysis, infrared spectroscopy, thermogravimetric analysis, and electrospray ionization mass spectrometry, which remarkably showed that all the clusters, even the largest cluster, 10 (∼50 kD), could be observed as the intact cluster demonstrating the extraordinary potential of this approach to construct robust gigantic nanoscale polyoxotungstates. PMID:23244039

  9. p-Sulfonic Acid Calix[4]arene as an Efficient Catalyst for One-Pot Synthesis of Pharmaceutically Significant Coumarin Derivatives under Solvent-Free Condition

    PubMed Central

    Tashakkorian, Hamed; Lakouraj, Moslem Mansour; Rouhi, Mona

    2015-01-01

    One-pot and efficient protocol for preparation of some potent pharmaceutically valuable coumarin derivatives under solvent-free condition via direct coupling using biologically nontoxic organocatalyst, calix[4]arene tetrasulfonic acid (CSA), was introduced. Calix[4]arene sulfonic acid has been incorporated lately as a magnificent and recyclable organocatalyst for the synthesis of some organic compounds. Nontoxicity, solvent-free conditions, good-to-excellent yields for pharmaceutically significant structures, and especially ease of catalyst recovery make this procedure valuable and environmentally benign. PMID:26798517

  10. Pseudo five-component synthesis of 2,5-di(hetero)arylthiophenes via a one-pot Sonogashira-Glaser cyclization sequence.

    PubMed

    Urselmann, Dominik; Antovic, Dragutin; Müller, Thomas J J

    2011-01-01

    Based upon a consecutive one-pot Sonogashira-Glaser coupling-cyclization sequence a variety of 2,5-di(hetero)arylthiophenes were synthesized in moderate to good yields. A single Pd/Cu-catalyst system, without further catalyst addition, and easily available, stable starting materials were used, resulting in a concise and highly efficient route for the synthesis of the title compounds. This novel pseudo five-component synthesis starting from iodo(hetero)arenes is particularly suitable as a direct access to well-defined thiophene oligomers, which are of peculiar interest in materials science. PMID:22238523

  11. One-Pot Ketone Synthesis with Alkylzinc Halides Prepared from Alkyl Halides via a Single Electron Transfer (SET) Process: New Extension of Fukuyama Ketone Synthesis.

    PubMed

    Lee, Jung Hwa; Kishi, Yoshito

    2016-06-01

    One-pot ketone synthesis has been developed with in situ activation of alkyl halides to alkylzinc halides in the presence of thioesters and Pd-catalyst. The new method provides us with a reliable option for a coupling at a late stage in a convergent synthesis of complex molecules, with use of a near 1:1 molar ratio of coupling partners. First, two facile, orthogonal methods have been developed for preparation of alkylzinc halides: (1) direct insertion of zinc dust to 1°- and 2°-alkyl halides in the presence of LiI in DMI and (2) early transition-metal assisted activation of alkyl halides via a single electron transfer (SET) process. CrCl2 has been found as an unprecedented, inevitable mediator for preparation of alkylzinc halides from alkyl halides, where CrCl2 likely functions to trap R·, generated via a SET process, and transfer it to Zn(II) to form RZnX. In addition to a commonly used CoPc, a new radical initiator NbCpCl4 has been discovered through the study. Second, with use of the two orthogonal methods, three sets of coupling conditions have been developed to complete one-pot ketone synthesis, with Condition A (Pd2dba3, PR3, Zn, LiI, TESCl, DMI), Condition B (A + CrCl2), and Condition C (B + NbCpCl4 or CoPc) being useful for simple linear and α-substituted substrates, simple linear and β-substituted substrates, and complex substrates, respectively. Condition C is applicable to the broadest range of substrates. Overall, one-pot ketone synthesis gives excellent yields, with good functional group tolerance. Controlled formation of alkylzinc halides by a combination of CrCl2 and NbCpCl4 or CoPc is crucial for its application to complex substrates. Interestingly, one-pot ketone synthesis does not suffer from the chemical instability due to the inevitable radical pathway(s), for example a 1,5-H shift. Notably, even with the increase in molecular size, no significant decrease in coupling efficiency has been noticed. To illustrate the synthetic value at a late

  12. Interface-coupled dissolution-precipitation processes during acidic weathering of multicomponent minerals

    NASA Astrophysics Data System (ADS)

    Ruiz-Agudo, Encarnacion; King, Helen E.; Patiño-López, Luis D.; Putnis, Christine V.; Geisler, Thorsten; Rodriguez-Navarro, Carlos M.; Putnis, Andrew

    2015-04-01

    The chemical weathering of carbonate and silicate minerals on the Earth's surface controls important geochemical processes such as erosion rates and soil formation, ore genesis or climate evolution. The dissolution of most of these minerals is typically incongruent, and results in the formation of surface coatings (altered layers, also known as leached layers). These coatings may significantly affect mineral dissolution rates over geological timescales, and therefore a great deal of research has been conducted on them. However, the mechanism of leached layer formation is a matter of vigorous debate. Here we report on an in situ atomic force microscopy (AFM) and real-time Mach-Zehnder phase-shift interferometry (PSI) study of the dissolution of wollastonite, CaSiO3, and dolomite, CaMg(CO3)2, as an example of surface coating formation during acidic weathering of multicomponent minerals. Our in situ results provide clear direct experimental evidence that leached layers are formed in a tight interface-coupled two-step process: stoichiometric dissolution of the pristine mineral surfaces and subsequent precipitation of a secondary phase (silica in the case of wollastonite, or hydrated magnesium carbonate in the case of dolomite) from a supersaturated boundary layer of fluid in contact with the mineral surface. This occurs despite the bulk solution remaining undersaturated with respect to the secondary phase. The validation of such a mechanism given by the results reported here completely changes the conceptual framework concerning the mechanism of chemical weathering, and differs significantly from the concept of preferential leaching of cations postulated by most currently accepted incongruent dissolution models.

  13. One-pot laser-assisted synthesis of porous carbon with embedded magnetic cobalt nanoparticles

    NASA Astrophysics Data System (ADS)

    Ghimbeu, Camélia Matei; Sopronyi, Mihai; Sima, Felix; Delmotte, Luc; Vaulot, Cyril; Zlotea, Claudia; Paul-Boncour, Valérie; Le Meins, Jean-Marc

    2015-05-01

    A novel one-pot laser-assisted approach is reported herein for the synthesis of ordered carbons with embedded cobalt nanoparticles. The process is based on a UV pulsed laser exposure of an ethanolic solution consisting of green carbon precursors, a structure directing agent and a cobalt salt. Very short irradiation times (5 to 30 min) are only required to polymerize and cross-link carbon precursors (i.e. phloroglucinol and glyoxylic acid) independent of a catalyst presence. The influence of three metallic salts (acetate, nitrate and chloride) on the phenolic resin and carbon characteristics (structure, texture and particle size/distribution) was systematically studied. When exposed to UV laser, the metallic salt exhibited a strong influence on the particle size and distribution in the carbon matrix rather than on the textural carbon properties. Using cobalt acetate, very small (3.5 nm) and uniformly dispersed particles were obtained by this simple, fast and green one-pot synthesis approach. An original combined 13C CP-MAS and DP-DEC solid state NMR spectroscopy analysis allowed to determine the structure of phenolic resins as well as the location of the cobalt salt in the resin. Complementarily, the 1H solid-state and relaxation NMR provided unique insights into the rigidity (cross-linking) of the phenolic resin and dispersion of the cobalt salt. The magnetic properties of cobalt nanoparticles were found to be size-dependent: large Co nanoparticles (~50 nm) behave as bulk Co whereas small Co nanoparticles are superparamagnetic.A novel one-pot laser-assisted approach is reported herein for the synthesis of ordered carbons with embedded cobalt nanoparticles. The process is based on a UV pulsed laser exposure of an ethanolic solution consisting of green carbon precursors, a structure directing agent and a cobalt salt. Very short irradiation times (5 to 30 min) are only required to polymerize and cross-link carbon precursors (i.e. phloroglucinol and glyoxylic acid

  14. Facile One-Pot Polyol Method for the Synthesis of Uniform Size Silver Nanowires.

    PubMed

    Kaili, Zhang; Yongguo, Du; Shimin, Chen

    2016-01-01

    This study reports the development of a facile and efficient one-pot polyol method for the synthesis of silver nanowires. The seed and growth of silver nanowires under different reaction conditions were characterized and measured. The pertinent variables such as temperature, time, concentration and capping agent were investigated. Moreover, the effect of seeding at two different stages-initial stage and secondary stage-was studied and discussed on the size control of silver nanowires. In particular, silver nanowires with diameter less than 40 nm and length over 25 µm in a narrow distribution, was obtained through a novel method in which reaction flask was placed in a low-temperature bath after seeding for some time in the high-temperature bath. This approach may be useful for the fabrication of uniform, large aspect ratio silver nanowires for optoelectronic applications. PMID:27398477

  15. A facile one-pot method to synthesize ultrasmall core-shell superparamagnetic and upconversion nanoparticles.

    PubMed

    Cheng, Qian; Guo, Hongxuan; Li, Yu; Liu, Shouxin; Sui, Jiehe; Cai, Wei

    2016-08-01

    Ultrasmall core-shell Fe3O4@NaYF4:Yb(3+)/Er(3+) nanoparticles with bifunctional properties have been successfully synthesized via one pot thermolysis method using oleylamine as both solvent and stabilizer. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), upconversion (UC) luminescence spectra and the physical properties measurement system (PPMS) were used to characterize the resulting samples. The synthesized samples have uniform morphology with a mean size of 14.5nm and excellent dispersibility. Moreover, these nanoparticles exhibit superparamagnetic behaviour with saturation magnetization of 8.45emμ/g and efficient up-conversion emission with a two-photon induced process when excited by a 980nm laser. These results suggest that the synthesized ultrasmall bifunctional nanoparticles may find many biomedical applications, such as clinical diagnosis and treatment of cancers. PMID:27135942

  16. Improved one-pot multienzyme (OPME) systems for synthesizing UDP-uronic acids and glucuronides†

    PubMed Central

    Muthana, Musleh M.; Qu, Jingyao; Xue, Mengyang; Klyuchnik, Timofey; Siu, Alex; Li, Yanhong; Zhang, Lei; Yu, Hai; Li, Lei; Wang, Peng G.

    2015-01-01

    Arabidopsis thaliana glucuronokinase (AtGlcAK) was cloned and shown to be able to use various uronic acids as substrates to produce the corresponding uronic acid-1-phosphates. AtGlcAK or Bifidobacterium infantis galactokinase (BiGalK) was used with a UDP-sugar pyrophosphorylase, an inorganic pyrophosphatase, with or without a glycosyltransferase for highly efficient synthesis of UDP-uronic acids and glucuronides. These improved cost-effective one-pot multienzyme (OPME) systems avoid the use of nicotinamide adenine dinucleotide (NAD+)-cofactor in dehydrogenase-dependent UDP-glucuronic acid production processes and can be broadly applied for synthesizing various glucuronic acid-containing molecules. PMID:25686901

  17. A Short, One-Pot Synthesis of Bupropion (Zyban®, Wellbutrin®)

    NASA Astrophysics Data System (ADS)

    Perrine, Daniel M.; Ross, Jason T.; Nervi, Stephen J.; Zimmerman, Richard H.

    2000-11-01

    A one-pot synthesis of (±)-2-(t-butylamino)-3'-chloropropiophenone (bupropion) as its hydrochloride salt (Zyban, Wellbutrin), an important antidepressant drug used in the treatment of nicotine addiction, is described. The procedure, suitable for students in their first year of organic chemistry, can be carried out in less than two hours and provides material of high purity in overall yield of 75-85%. A solution of m-chloropropiophenone in CH2Cl2 is treated with Br2. After removal of the solvent, t-butylamine and N-methylpyrrolidinone are added and the mixture is warmed briefly, quenched with water, and extracted with ether. Concentrated HCl is added to the ether solution to precipitate the product.

  18. Environmentally friendly efficient one-pot esterification of cyclohexane with CuO-promoted sulfated zirconia.

    PubMed

    Wang, Jingjing; Ma, Hongzhu; Wang, Bo

    2008-09-15

    The production of dibutyl phthalate directly from oxidation and esterification of cyclohexane, catalyzed by CuO-modified sulfated zirconia (SZCu) by one-pot under mild condition, was studied. The esterification reaction process was monitored by UV-vis spectra and the distribution of the products was analyzed by gas chromatograph-mass spectrometry (GC-MS). The result revealed that the SZCu catalyst was efficient in the direct oxidation and esterification of cyclohexane to ester. The selectivity for ester (dibutyl phthalate) can reach up to 72.2 wt.%, and the yield of ester was 29.5 wt.%. The esterification reaction, that offers several advantages such as usage of environmental friendly oxidant, simple work-up procedure, no-solvent conditions, short reaction times, easy recovery and reusability of the catalyst, is necessary for chemosynthesis industry from the environment standpoint. The regeneration property of SZCu was also tested in this work. PMID:18258360

  19. One-Pot Amide Bond Formation from Aldehydes and Amines via a Photoorganocatalytic Activation of Aldehydes.

    PubMed

    Papadopoulos, Giorgos N; Kokotos, Christoforos G

    2016-08-19

    A mild, one-pot, and environmentally friendly synthesis of amides from aldehydes and amines is described. Initially, a photoorganocatalytic reaction of aldehydes with di-isopropyl azodicarboxylate leads to an intermediate carbonyl imide, which can react with a variety of amines to afford the desired amides. The initial visible light-mediated activation of a variety of monosubstituted or disubstituted aldehydes is usually fast, occurring in a few hours. Following the photocatalytic reaction, addition of the primary amine at room temperature or the secondary amine at elevated temperatures leads to the corresponding amide from moderate to excellent yields without epimerization. This methodology was applied in the synthesis of Moclobemide, a drug against depression and social anxiety. PMID:27227271

  20. Facile one-pot synthesis of polytypic CuGaS2 nanoplates

    NASA Astrophysics Data System (ADS)

    Liu, Zhongping; Hao, Qiaoyan; Tang, Rui; Wang, Linlin; Tang, Kaibin

    2013-12-01

    CuGaS2 (CGS) nanoplates were successfully synthesized by one-pot thermolysis of a mixture solution of CuCl, GaCl3, and 1-dodecanethiol in noncoordinating solvent 1-octadecene. Their morphology, crystalline phase, and composition were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), powder X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. Crystalline structure analysis showed that the as-prepared CGS nanoplates were polytypic, in which the wurtzite phase was interfaced with zincblende domains. The growth process of CGS nanoplates was investigated. It was found that copper sulfide nanoplates were firstly formed and then the as-formed copper sulfide nanoplates gradually transformed to CGS nanoplates with proceeding of the reaction. The optical absorption of the as-synthesized CGS nanoplates was also measured and the direct optical bandgap was determined to be 2.24 eV.

  1. A facile one-pot method to Au–SnO{sub 2}-graphene ternary hybrid

    SciTech Connect

    Xu, Diou; Li, Xiaotian; Zhang, Dawei

    2014-11-15

    In this article, we propose a facile one-pot route for synthesizing Au–SnO{sub 2}-graphene ternary hybrid. In the system, SnCl{sub 2} not only as the precursor of SnO{sub 2}, but also is employed as reducing agent for the effective reduction of both GO and HAuCl{sub 4} to graphene and Au nanoparticles, respectively. The obtained Au–SnO{sub 2}-graphene hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, X-ray diffraction, Raman spectrum, X-ray photo-electron spectroscopy, and thermal gravimetric analysis. It is found that the content of Au nanoparticles decorated on the surface of graphene can be simply adjusted by changing the amount of HAuCl{sub 4} used in the synthesis process.

  2. Chemoselective reduction of the carbonyl functionality through hydrosilylation: integrating click catalysis with hydrosilylation in one pot.

    PubMed

    Roy, Sudipta Raha; Sau, Samaresh Chandra; Mandal, Swadhin K

    2014-10-01

    Herein we report the chemoselective reduction of the carbonyl functionality via hydrosilylation using a copper(I) catalyst bearing the abnormal N-heterocyclic carbene 1 with low (0.25 mol %) catalyst loading at ambient temperature in excellent yield within a very short reaction time. The hydrosilylation reaction of α,β-unsaturated carbonyl compounds takes place selectively toward 1,2-addition (C═O) to yield the corresponding allyl alcohols in good yields. Moreover, when two reducible functional groups such as imine and ketone groups are present in the same molecule, this catalyst selectively reduces the ketone functionality. Further, 1 was used in a consecutive fashion by combining the Huisgen cycloaddition and hydrosilylation reactions in one pot, yielding a range of functionalized triazole substituted alcohols in excellent yields. PMID:25188382

  3. Graphene/NiO nanowires: controllable one-pot synthesis and enhanced pseudocapacitive behavior.

    PubMed

    Dam, Duc Tai; Wang, Xin; Lee, Jong-Min

    2014-06-11

    In this study, we report a facile and simple approach to synthesize a composite of mesoporous NiO nanowires and graphene nanosheets for supercapacitor applications. A Ni precursor was prepared by a one-pot sol-gel method in a water/ethylene glycol mixture containing a graphene oxide. Heat treatment in air was carried out to thermally reduce the graphene oxide to graphene and to convert the Ni precursor to NiO. NiO nanowires possess a rough surface, have a diameter of around 60 nm and are homogeneously deposited on the graphene sheets. The NiO/graphene nanocomposite demonstrates superior pseudocapacitive properties (high specific capacitance, good cyclic performance, and excellent discharge rate capability) as compared to its counterparts. We postulated that this phenomenon arose from the synergistic effect of the addition of graphene as elastic conductive channels, which resulted in better charge transport and more favorable ionic diffusion. PMID:24846201

  4. One-pot synthesis of PVA-capped silver nanoparticles their characterization and biomedical application

    NASA Astrophysics Data System (ADS)

    Patil, Rupali S.; Kokate, Mangesh R.; Jambhale, Chitra L.; Pawar, Sambhaji M.; Han, Sung H.; Kolekar, Sanjay S.

    2012-03-01

    The rapid one-pot synthesis of silver nanoparticles (SNPs) at room temperature by using hydrazine hydrate as reducing agent and polyvinyl alcohol as stabilizing agent is reported. The SNPs were characterized with UV-visible (UV-Vis) spectroscopy, x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM). The synthesized silver nanoparticle shows surface plasmon resonance at 410 nm. The XRD reveals face-centered cubic (FCC) structure of SNPs. FE-SEM, AFM and TEM show that nanoparticles have spherical morphology with diameters in the range of 10–60 nm. The antimicrobial activity of synthesized hybrid material against strains of four different bacteria (Bacillus cereus, Escherichia coli, Staphylococus aureus, Proteus vulgaris), that are commonly found in hospitals has been studied. The results indicate that such particles have potential applications in biotechnology and biomedical science.

  5. Efficient One-Pot Synthesis of Colloidal Zirconium Oxide Nanoparticles for High-Refractive-Index Nanocomposites.

    PubMed

    Liu, Chao; Hajagos, Tibor Jacob; Chen, Dustin; Chen, Yi; Kishpaugh, David; Pei, Qibing

    2016-02-01

    Zirconium oxide nanoparticles are promising candidates for optical engineering, photocatalysis, and high-κ dielectrics. However, reported synthetic methods for the colloidal zirconium oxide nanoparticles use unstable alkoxide precursors and have various other drawbacks, limiting their wide application. Here, we report a facile one-pot method for the synthesis of colloidally stable zirconium oxide nanoparticles. Using a simple solution of zirconium trifluoroacetate in oleylamine, highly stable zirconium oxide nanoparticles have been synthesized with high yield, following a proposed amidization-assisted sol-gel mechanism. The nanoparticles can be readily dispersed in nonpolar solvents, forming a long-term stable transparent solution, which can be further used to fabricate high-refractive-index nanocomposites in both monolith and thin-film forms. In addition, the same method has also been extended to the synthesis of titanium oxide nanoparticles, demonstrating its general applicability to all group IVB metal oxide nanoparticles. PMID:26824518

  6. Microwave-assisted, one-pot syntheses and fungicidal activity of polyfluorinated 2-benzylthiobenzothiazoles.

    PubMed

    Huang, Wei; Yang, Guang-Fu

    2006-12-15

    Polyfluorinated 2-benzylthiobenzothiazoles 3a-l are prepared via a microwave-assisted, one-pot procedure. The advantages, such as good to excellent yields, shorter reaction time (14-21min), readily available starting material, and simple purification procedure, distinguish the present protocol from other existing methods used for the synthesis of 2-benzylthiobenzothiazoles. Bioassay indicated that most of the compounds showed significant fungicidal activity against Rhizoctonia solani, Botrytis cinereapers, and Dothiorella gregaria at a dosage of 50microg/mL. Interestingly, compared to the control of commercial fungicide, triadimefon, compound 3c exhibited much higher activities against R. solani, B. cinereapers, and D. gregaria, which showed that the polyfluorinated 2-benzylthiobenzothiazoles can be used as lead compound for developing novel fungicides. PMID:17008103

  7. Polymer immobilized Cu(I) formation and azide-alkyne cycloaddition: A one pot reaction

    PubMed Central

    Islam, Rafique Ul; Taher, Abu; Choudhary, Meenakshi; Siwal, Samarjeet; Mallick, Kaushik

    2015-01-01

    During the polymerization of aniline using copper sulphate, act as an oxidizing agent, the in-situ synthesized Cu(I) ion catalyzed the cyclo-addition between azides and alkynes. This work represents the merging of two steps, synthesis of the catalyst and application of the catalyst, in a one pot reaction. The elimination of the separate catalyst synthesis step is economic in terms of cost and time. As aniline was used as one of the reactant components so there is no requirement to use additional base for this reaction that further eliminates the cost of the process. Again, the catalyst can be readily recovered by filtration and efficiently used for the several sets of reactions without any significant loss of catalytic activity. PMID:25966018

  8. An In Situ One-Pot Synthetic Approach towards Multivariate Zirconium MOFs.

    PubMed

    Sun, Yujia; Sun, Lixian; Feng, Dawei; Zhou, Hong-Cai

    2016-05-23

    Chemically highly stable MOFs incorporating multiple functionalities are of great interest for applications under harsh environments. Herein, we presented a facile one-pot synthetic strategy to incorporate multiple functionalities into stable Zr-MOFs from mixed ligands of different geometry and connectivity. Via our strategy, tetratopic tetrakis(4-carboxyphenyl)porphyrin (TCPP) ligands were successfully integrated into UiO-66 while maintaining the crystal structure, morphology, and ultrahigh chemical stability of UiO-66. The amount of incorporated TCPP is controllable. Through various combinations of BDC derivatives and TCPP, 49 MOFs with multiple functionalities were obtained. Among them, MOFs modified with FeTCPPCl were demonstrated to be catalytically active for the oxidation of ABTS. We anticipate our strategy to provide a facile route to introduce multiple functionalities into stable Zr-MOFs for a wide variety of potential applications. PMID:27100570

  9. Tuneable light-emitting carbon-dot/polymer flexible films prepared through one-pot synthesis.

    PubMed

    Bhunia, Susanta Kumar; Nandi, Sukhendu; Shikler, Rafi; Jelinek, Raz

    2016-02-14

    Development of efficient, inexpensive, and environmentally-friendly light emitters, particularly devices that produce white light, have drawn intense interest due to diverse applications in the lighting industry, photonics, solar energy, and others. We present a simple strategy for the fabrication of flexible transparent films exhibiting tuneable light emission through one-pot synthesis of polymer matrixes with embedded carbon dots assembled in situ. Importantly, different luminescence colours were produced simply by preparing C-dot/polymer films using carbon precursors that yielded C-dots exhibiting distinct fluorescence emission profiles. Furthermore, mixtures of C-dot precursors could be also employed for fabricating films exhibiting different colours. In particular, we successfully produced films emitting white light with attractive properties (i.e."warm" white light with a high colour rendering index) - a highly sought after goal in optical technologies. PMID:26791813

  10. One-pot laser-assisted synthesis of porous carbon with embedded magnetic cobalt nanoparticles.

    PubMed

    Ghimbeu, Camélia Matei; Sopronyi, Mihai; Sima, Felix; Delmotte, Luc; Vaulot, Cyril; Zlotea, Claudia; Paul-Boncour, Valérie; Le Meins, Jean-Marc

    2015-06-14

    A novel one-pot laser-assisted approach is reported herein for the synthesis of ordered carbons with embedded cobalt nanoparticles. The process is based on a UV pulsed laser exposure of an ethanolic solution consisting of green carbon precursors, a structure directing agent and a cobalt salt. Very short irradiation times (5 to 30 min) are only required to polymerize and cross-link carbon precursors (i.e. phloroglucinol and glyoxylic acid) independent of a catalyst presence. The influence of three metallic salts (acetate, nitrate and chloride) on the phenolic resin and carbon characteristics (structure, texture and particle size/distribution) was systematically studied. When exposed to UV laser, the metallic salt exhibited a strong influence on the particle size and distribution in the carbon matrix rather than on the textural carbon properties. Using cobalt acetate, very small (3.5 nm) and uniformly dispersed particles were obtained by this simple, fast and green one-pot synthesis approach. An original combined (13)C CP-MAS and DP-DEC solid state NMR spectroscopy analysis allowed to determine the structure of phenolic resins as well as the location of the cobalt salt in the resin. Complementarily, the (1)H solid-state and relaxation NMR provided unique insights into the rigidity (cross-linking) of the phenolic resin and dispersion of the cobalt salt. The magnetic properties of cobalt nanoparticles were found to be size-dependent: large Co nanoparticles (∼50 nm) behave as bulk Co whereas small Co nanoparticles are superparamagnetic. PMID:25981107

  11. Tuneable light-emitting carbon-dot/polymer flexible films prepared through one-pot synthesis

    NASA Astrophysics Data System (ADS)

    Bhunia, Susanta Kumar; Nandi, Sukhendu; Shikler, Rafi; Jelinek, Raz

    2016-02-01

    Development of efficient, inexpensive, and environmentally-friendly light emitters, particularly devices that produce white light, have drawn intense interest due to diverse applications in the lighting industry, photonics, solar energy, and others. We present a simple strategy for the fabrication of flexible transparent films exhibiting tuneable light emission through one-pot synthesis of polymer matrixes with embedded carbon dots assembled in situ. Importantly, different luminescence colours were produced simply by preparing C-dot/polymer films using carbon precursors that yielded C-dots exhibiting distinct fluorescence emission profiles. Furthermore, mixtures of C-dot precursors could be also employed for fabricating films exhibiting different colours. In particular, we successfully produced films emitting white light with attractive properties (i.e. ``warm'' white light with a high colour rendering index) - a highly sought after goal in optical technologies.Development of efficient, inexpensive, and environmentally-friendly light emitters, particularly devices that produce white light, have drawn intense interest due to diverse applications in the lighting industry, photonics, solar energy, and others. We present a simple strategy for the fabrication of flexible transparent films exhibiting tuneable light emission through one-pot synthesis of polymer matrixes with embedded carbon dots assembled in situ. Importantly, different luminescence colours were produced simply by preparing C-dot/polymer films using carbon precursors that yielded C-dots exhibiting distinct fluorescence emission profiles. Furthermore, mixtures of C-dot precursors could be also employed for fabricating films exhibiting different colours. In particular, we successfully produced films emitting white light with attractive properties (i.e. ``warm'' white light with a high colour rendering index) - a highly sought after goal in optical technologies. Electronic supplementary information (ESI

  12. Direct one-pot synthesis of chemically anisotropic particles with tunable morphology, dimensions, and surface roughness.

    PubMed

    Liu, Yanan; Liu, Wang; Ma, Yuhong; Liu, Lianying; Yang, Wantai

    2015-01-27

    Previously, synthesis of anisotropic particles by seeded polymerizations has involved multiple process steps. In conventional one-pot dispersion polymerization (Dis.P) with a cross-linker added, only spherical particles are produced due to rapid and high cross-linking. In this Article, a straightforward one-pot preparation of monodisperse anisotropic particles with tunable morphology, dimensions, surface roughness, and asymmetrically distributed functional groups is described. With a cross-linker of divinylbenzene (DVB, 8%), ethylene glycol dimethacrylate (EGDMA, 6%), or dimethacryloyloxybenzophenone (DMABP, 5%) added at 40 min, shortly after the end of nucleation stage in Dis.P of styrene (St) in methanol and water (6/4, vol), the swollen growing particles are inhomogeneously cross-linked at first. Then, at low gel contents of 59%, 49%, and 69%, corresponding to the cases using DVB, EGDMA, and DMABP, respectively, the growing particle phase separates and snowman- or dumbbell-like particles are generated. Thermodynamic and kinetic analyses reveal that moderate cross-linking and sufficient swelling of growing particles determine the formation and growth of anisotropic particles during polymerization. Morphology, surface roughness, sizes, and cross-linking degrees of each domain of final particles are tuned continuously by varying start addition time and contents of cross-linkers. The snowman-like particles fabricated with DVB have a gradient cross-linking and asymmetrical distribution of pendant vinyl groups from their body to head. The dumbbell-like particles prepared using DMABP have only one domain cross-linked; i.e., only one domain contains photosensitive benzophenone (BP) groups. With addition of glycidyl methacrylate (GMA) or propargyl methacrylate (PMA) together with DVB or EGDMA, epoxy or alkynyl groups are asymmetrically incorporated. With the aid of these functional groups, carboxyl, amino, or thiol groups and PEG (200) are attached by thiol-ene (yne

  13. One-pot three-enzyme chemoenzymatic approach to the synthesis of sialosides containing natural and non-natural functionalities

    PubMed Central

    Yu, Hai; Chokhawala, Harshal; Huang, Shengshu; Chen, Xi

    2008-01-01

    Chemoenzymatic synthesis, which combines the flexibility of chemical synthesis and the highly selectivity of enzymatic synthesis, is a powerful approach to obtain complex carbohydrates. It is a preferred method for synthesizing sialic acid-containing structures, including those with diverse naturally occurring and non-natural sialic acid forms, different sialyl linkages, and different glycans that link to the sialic acid. Starting from N-acetylmannosamine, mannose, or their chemically or enzymatically modified derivatives, sialic acid aldolase-catalyzed condensation reaction leads to the formation of sialic acids and their derivatives. These compounds are subsequently activated by a CMP-sialic acid synthetase and transferred to a wide range of suitable acceptors by a suitable sialyltransferase for the formation of sialosides containing natural and non-natural functionalities. The three-enzyme coupled synthesis of sialosides can be carried out in one pot without the isolation of intermediates. The time for synthesis is 4–18 h. Purification and characterization of the product can be completed in 2–3 d. PMID:17406495

  14. Synthesis of Lithium Boracarbonate Ion Pairs by Copper-Catalyzed Multi-Component Coupling of Carbon Dioxide, Diboron, and Aldehydes.

    PubMed

    Carry, Béatrice; Zhang, Liang; Nishiura, Masayoshi; Hou, Zhaomin

    2016-05-17

    The catalytic selective multi-component coupling of CO2 , bis(pinacolato)diboron, LiOtBu, and a wide range of aldehydes has been achieved for the first time by using an NHC-copper catalyst. This transformation has efficiently afforded a series of novel lithium cyclic boracarbonate ion pair compounds in high yields from readily available starting materials. This protocol has not only provided a new catalytic process for the utilization of CO2 , but it has also constituted a novel route for the efficient synthesis of a new class of lithium borate compounds that might be of interest as potential electrolyte candidates for lithium ion batteries. PMID:27061244

  15. A liquid state least-squares procedure for obtaining solid state multicomponent diffusion coefficients from diffusion couples

    SciTech Connect

    Miller, D.G.

    1998-11-02

    A procedure is developed for analyzing combined concentration profiles from multicomponent solid-state diffusion data obtained with free-diffusion boundary conditions. This procedure is exactly analogous to the analysis of liquid-state diffusion data obtained from free-diffusion refractive-index profiles (e.g. from Rayleigh interferometry). All data from all couples are least-squared together to characterize the diffusion coefficient matrix. Different profile weightings provide interesting alternatives, as well as diagnostics. Symmetric averagings are shown to eliminate or reduce effects of concentration dependence.

  16. One-pot synthesis of active copper-containing carbon dots with laccase-like activities

    NASA Astrophysics Data System (ADS)

    Ren, Xiangling; Liu, Jing; Ren, Jun; Tang, Fangqiong; Meng, Xianwei

    2015-11-01

    Herein, an effective strategy for designing a new type of nanozyme, blue fluorescent laccase mimics, is reported. Active copper-containing carbon dots (Cu-CDs) were synthesized through a simple, nontoxic and one-pot hydrothermal method, which showed favorable photoluminescence properties and good photostability under high-salt conditions or in a broad pH range (3.0-13.5). The Cu-CDs possessed intrinsic laccase-like activities and could catalyze the oxidation of the laccase substrate p-phenylenediamine (PPD) to produce a typical color change from colorless to brown. Poly(methacrylic acid sodium salt) (PMAA) not only was used as the carbon source and reducing agent, but also provided carboxyl groups to assist flocculation between Cu-CDs and polyacrylamide, which facilitated the removal of PPD. Importantly, the intrinsic fluorescence of the as-prepared Cu-CDs could indicate the presence of hydroquinone, one of the substrates of laccases, based on laccase mimics and fluorescence quenching.Herein, an effective strategy for designing a new type of nanozyme, blue fluorescent laccase mimics, is reported. Active copper-containing carbon dots (Cu-CDs) were synthesized through a simple, nontoxic and one-pot hydrothermal method, which showed favorable photoluminescence properties and good photostability under high-salt conditions or in a broad pH range (3.0-13.5). The Cu-CDs possessed intrinsic laccase-like activities and could catalyze the oxidation of the laccase substrate p-phenylenediamine (PPD) to produce a typical color change from colorless to brown. Poly(methacrylic acid sodium salt) (PMAA) not only was used as the carbon source and reducing agent, but also provided carboxyl groups to assist flocculation between Cu-CDs and polyacrylamide, which facilitated the removal of PPD. Importantly, the intrinsic fluorescence of the as-prepared Cu-CDs could indicate the presence of hydroquinone, one of the substrates of laccases, based on laccase mimics and fluorescence quenching

  17. Isothermal DNA origami folding: avoiding denaturing conditions for one-pot, hybrid-component annealing

    NASA Astrophysics Data System (ADS)

    Kopielski, Andreas; Schneider, Anne; Csáki, Andrea; Fritzsche, Wolfgang

    2015-01-01

    The DNA origami technique offers great potential for nanotechnology. Using biomolecular self-assembly, defined 2D and 3D nanoscale DNA structures can be realized. DNA origami allows the positioning of proteins, fluorophores or nanoparticles with an accuracy of a few nanometers and enables thereby novel nanoscale devices. Origami assembly usually includes a thermal denaturation step at 90 °C. Additional components used for nanoscale assembly (such as proteins) are often thermosensitive, and possibly damaged by such harsh conditions. They have therefore to be attached in an extra second step to avoid defects. To enable a streamlined one-step nanoscale synthesis - a so called one-pot folding - an adaptation of the folding procedures is required. Here we present a thermal optimization of this process for a 2D DNA rectangle-shaped origami resulting in an isothermal assembly protocol below 60 °C without thermal denaturation. Moreover, a room temperature protocol is presented using the chemical additive betaine, which is biocompatible in contrast to chemical denaturing approaches reported previously.The DNA origami technique offers great potential for nanotechnology. Using biomolecular self-assembly, defined 2D and 3D nanoscale DNA structures can be realized. DNA origami allows the positioning of proteins, fluorophores or nanoparticles with an accuracy of a few nanometers and enables thereby novel nanoscale devices. Origami assembly usually includes a thermal denaturation step at 90 °C. Additional components used for nanoscale assembly (such as proteins) are often thermosensitive, and possibly damaged by such harsh conditions. They have therefore to be attached in an extra second step to avoid defects. To enable a streamlined one-step nanoscale synthesis - a so called one-pot folding - an adaptation of the folding procedures is required. Here we present a thermal optimization of this process for a 2D DNA rectangle-shaped origami resulting in an isothermal assembly

  18. Combining the 'two worlds' of chemocatalysis and biocatalysis towards multi-step one-pot processes in aqueous media.

    PubMed

    Gröger, Harald; Hummel, Werner

    2014-04-01

    The combination of biocatalytic and chemocatalytic reactions leading to one-pot processes in aqueous medium represents an economically and ecologically attractive concept in organic synthesis due to the potential to avoid time and capacity consuming and waste producing work-up steps of intermediates. The use of water as a solvent has many advantages. A key feature is the opportunity it provides as the solvent in nature to make use of the full range of enzymes. In recent years development of chemoenzymatic one-pot processes in water has emerged tremendously, and proof of concepts for the combination of biotransformations with metal catalysts and organocatalysts were demonstrated. This review will focus on major contributions in this field, which also underline the compatibility of these two 'worlds' of catalysis with each other as well as the industrial potential of this one-pot approach. PMID:24709123

  19. Photothermal cancer therapy using graphitic carbon–coated magnetic particles prepared by one-pot synthesis

    PubMed Central

    Lee, Hyo-Jeong; Sanetuntikul, Jakkid; Choi, Eun-Sook; Lee, Bo Ram; Kim, Jung-Hee; Kim, Eunjoo; Shanmugam, Sangaraju

    2015-01-01

    We describe here a simple synthetic strategy for the fabrication of carbon-coated Fe3O4 (Fe3O4@C) particles using a single-component precursor, iron (III) diethylenetriaminepentaacetic acid complex. Physicochemical analyses revealed that the core of the synthesized particles consists of ferromagnetic Fe3O4 material ranging several hundred nanometers, embedded in nitrogen-doped graphitic carbon with a thickness of ~120 nm. Because of their photothermal activity (absorption of near-infrared [NIR] light), the Fe3O4@C particles have been investigated for photothermal therapeutic applications. An example of one such application would be the use of Fe3O4@C particles in human adenocarcinoma A549 cells by means of NIR-triggered cell death. In this system, the Fe3O4@C can rapidly generate heat, causing >98% cell death within 10 minutes under 808 nm NIR laser irradiation (2.3 W cm−2). These Fe3O4@C particles provided a superior photothermal therapeutic effect by intratumoral delivery and NIR irradiation of tumor xenografts. These results demonstrate that one-pot synthesis of carbon-coated magnetic particles could provide promising materials for future clinical applications and encourage further investigation of this simple method. PMID:25565819

  20. One pot phytosynthesis of gold nanoparticles using Genipa americana fruit extract and its biological applications.

    PubMed

    Kumar, Brajesh; Smita, Kumari; Cumbal, Luis; Camacho, Javier; Hernández-Gallegos, Elisabeth; de Guadalupe Chávez-López, María; Grijalva, Marcelo; Andrade, Kleber

    2016-05-01

    In this article, rapid one pot synthesis of gold nanoparticles (GNPs) using an eco-friendly extract of Genipa americana L. fruit is described. Electrospray ionization mass spectrometry (ESI-MS) and Fourier transform infrared (FTIR) spectroscopic studies demonstrated that small molecules such as genipin, genipaol, geniposide and ranolazine can act as reducer as well as stabilizers. The monodispersed, spherical GNPs were further characterized by UV-vis spectroscopy at λmax=535 nm, transmission electron microscopy (TEM), dynamic light scattering (DLS) and X-ray diffraction (XRD) analysis. This synthetic approach offers a greener and alternate route to the preparation of GNPs free from toxic chemical components and stable for 6-7 months under room temperature. The green synthesized GNPs showed weak antioxidant efficacy against 1,1-diphenyl-2-picrylhydrazyl and no cytotoxicity against A-549 and HeLa human cancer cell lines, from lung and cervix. This study opens a new industrial scope of G. americana fruit in nanoscience and as surface modified GNPs can be developed into a successful drug carrier for future pharmaceutical products. PMID:26952478

  1. One-pot synthesis and antimicrobial evaluation of novel 3-cyanopyridine derivatives of (-)-β-pinene.

    PubMed

    Liao, Shengliang; Shang, Shibin; Shen, Minggui; Rao, Xiaoping; Si, Hongyan; Song, Jie; Song, Zhanqian

    2016-03-15

    A series of novel 3-cyanopyridine derivatives of (-)-β-pinene were designed and synthesized by one-pot four-component domino reactions. The targeted compounds were evaluated for their antimicrobial activity against four bacteria (Klebsiella pneumoniae, Enterobacter aerogenes, Staphylococcus aureus, Staphylococcus epidermidis) and a fungus (Candida albicans). The results showed that most of the minimal inhibitory concentrations (MICs) of these 3-cyanopyridine derivatives against the tested strains was in the range of 15.6-125 mg/L. Among these 3-cyanopyridine derivatives, the MICs of compound 5h against S. epidermidis and C. albicans were 15.6 mg/L, which revealed that compound 5h featured double fluoro substituents at meta- and para-position was the most active compound. In addition, the preliminary structure-activity relationship analysis indicated that the change of substituents on the pyridine ring and benzene ring of 3-cyanopyridine derivatives was an important factor for inducing antimicrobial activity. This research would promote the development of heterocyclic derivatives of β-pinene with antimicrobial activity. PMID:26898336

  2. Direct application of gold nanoparticles to one-pot electrochemical biosensors.

    PubMed

    Chen, Guifang; Tong, Hui; Gao, Tao; Chen, Yangyang; Li, Genxi

    2014-11-01

    Gold nanoparticles (AuNPs) have been widely employed for the fabrication of electrochemical biosensors. In most cases, AuNPs are immobilized on the surface of an electrode, so they are difficult to be regenerated, making the use of the biosensor unfriendly. In this work, by adopting AuNPs directly as the electrolytes, we have developed a novel AuNPs-based electrochemical detection system. In brief, AuNPs-catalyzed oxidation of glucose is combined with a HRP-catalyzed reaction as well as an electrocatalytic reaction to compose cascade reactions in the electrolyte. Thus, the intensity of the electrocatalytic signals has quantitative relation with the concentration of glucose, and favors the sensitive detection of glucose. Furthermore, because the catalysis of AuNPs may be blocked under the interaction with single-stranded DNA and unblocked in the presence of a complementary sequence, detection of DNA and even single-nucleotide polymorphism can thereby been achieved. This one-pot detection system can be operated and regenerated very easily, since all the components are integrated in the electrolytes of AuNPs, and the unmodified electrode can be reused after being rinsed. This concept by integrating the advantages of sensitive electrochemical detection with the easy-to-operate nanocolloidal system may also promote the development of other kinds of electrochemical biosensors. PMID:25300210

  3. One-pot conversions of raffinose into furfural derivatives and sugar alcohols by using heterogeneous catalysts.

    PubMed

    Dabral, Saumya; Nishimura, Shun; Ebitani, Kohki

    2014-01-01

    Inedible and/or waste biomass reserves are being strongly focused upon as a suitable new energy and chemical source. Raffinose, which is an indigestible trisaccharide composed of glucose, galactose, and fructose, is found abundantly in beet molasses, sugar cane, and seeds of many leguminous plants. Herein, we demonstrate the one-pot synthesis of furan derivatives and sugar alcohols from raffinose by using heterogeneous acid, base, and/or metal-supported catalysts. The combination of Amberlyst-15 and hydrotalcite (HT) showed a high activity (37% yield) for 5-hydroxymethyl-2-furaldehyde (HMF) through continuous hydrolysis, isomerization, and dehydration reactions. In addition, the use of a hydrotalcite-supported ruthenium catalyst (Ru/HT) successfully afforded 2,5-diformylfuran (DFF, 27% yield) from HMF produced by raffinose, directly. Moreover, the hydrogenation of hexoses obtained by raffinose hydrolysis into sugar alcohols (galactitol, mannitol, sorbitol) was also achieved in a high yield (91%) with Amberlyst-15 and Ru/HT catalysts. Thus, we suggest that raffinose has great potential for the synthesis of important industrial intermediates under mild reaction conditions. PMID:24193816

  4. One-Pot synthesis of phosphorylated mesoporous carbon heterogeneous catalysts with tailored surface acidity

    SciTech Connect

    Fulvio, Pasquale F; Mahurin, Shannon Mark; Mayes, Richard T; Bauer, Christopher; Wang, Xiqing; Veith, Gabriel M; Dai, Sheng

    2012-01-01

    Soft-templated phosphorylated mesoporous carbons with homogeneous distributions of phosphate groups were prepared by a 'one-pot' synthesis method using mixtures of phosphoric acid with hydrochloric, or nitric acids in the presence of Pluronic F127 triblock copolymer. Adjusting the various ratios of phosphoric acid used in these mixtures resulted in carbons with distinct adsorption, structural and surface acidity properties. The pore size distributions (PSDs) from nitrogen adsorption at -196 C showed that mesoporous carbons exhibit specific surface areas as high as 551 m{sup 2}/g and mesopores as large as 13 nm. Both structural ordering of the mesopores and the final phosphate contents were strongly dependent on the ratios of H{sub 3}PO{sub 4} in the synthesis gels, as shown by transmission electron microscopy (TEM), X-ray photoelectron (XPS) and energy dispersive X-ray spectroscopy (EDS). The number of surface acid sites determined from temperature programmed desorption of ammonia (NH{sub 3}-TPD) were in the range of 0.3-1.5 mmol/g while the active surface areas are estimated to comprise 5-54% of the total surface areas. Finally, the conversion temperatures for the isopropanol dehydration were lowered by as much as 100 C by transitioning from the least acidic to the most acidic catalysts surface.

  5. One-pot synthesis and transfer of PMMA/Ag photonic nanocomposites by pulsed laser deposition

    NASA Astrophysics Data System (ADS)

    Karoutsos, V.; Koutselas, I.; Orfanou, P.; Mpatzaka, Th.; Vasileiadis, M.; Vassilakopoulou, A.; Vainos, N. A.; Perrone, A.

    2015-08-01

    Nanocomposite films comprising metallic nanoparticles in polymer matrices find increasing use in emerging photonic, electronic and microsystem applications owing to their tailored advanced functionalities. The versatile development of such films based on poly-methyl-methacrylate (PMMA) matrix having embedded Ag nanoparticles is addressed here. Two low-cost one-pot chemical methods for the synthesis of bulk target nanocomposite materials are demonstrated. These nanocomposites are subsequently transferred via pulsed laser deposition using 193 nm ArF excimer laser radiation, producing films maintaining the structural and functional properties. Both target- and laser-deposited materials have been thoroughly characterized using microscopic, spectroscopic and thermal analysis methods. Infrared spectra demonstrated the close molecular PMMA chain similarity for both target and film materials, though structural alterations identified by thermal analysis proved the enhanced characteristics of films grown. High-resolution electron microscopy proved the transfer of Ag nanoparticles sized 10-50 nm. Visible absorption peaked in the spectral range of 430-440 nm and attributed to the Ag nanocomposite plasmonic response verifying the transfer of the functional performance from target to film.

  6. Rapid, one-pot synthesis of highly-soluble carbon nanotubes functionalized by L-arginine

    NASA Astrophysics Data System (ADS)

    Ghiadi, Behnam; Baniadam, Majid; Maghrebi, Morteza; Amiri, Ahmad

    2013-04-01

    Functionalization of carbon nanotubes (CNTs) is a necessary step to exploit their valuable properties. Due to having several steps and especially acid treatment, most of current methods of functionalization result in irrecoverable defects on CNTs structure. Here, multiwalled carbon nanotubes (MWCNTs) were functionalized with L-arginine in a simple, one-pot and rapid microwave-assisted technique without any acid treatment step. The CNT functionalities were analyzed with infrared spectroscopy, thermogravimetric analysis, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results confirmed the covalent functionalization of L-arginine with very low defects on CNTs. Also it is found that increase of input powers of microwave in the range 500-900 W, monotonically increase the degree of functionalization. The maximum dispersibility of MWCNT was found ˜1.03 mg/mL corresponding to 900 W irradiation. Accounting considerable low treatment time, the method may be applied for large-scale solubilization of MWCNTs in an industrial scale.

  7. TiO2 Hollow Spheres: One-Pot Synthesis and Enhanced Photocatalysis

    NASA Astrophysics Data System (ADS)

    Jia, Changchao; Cao, Yongqiang; Yang, Ping

    2013-06-01

    Hollow TiO2 microspheres were successfully fabricated by metal salts with low solubility in ethanol acting as intelligent templates using a simple one-pot solvothermal method. Hollow spheres with large diameter were obtained using CuSO4ṡ5H2O as templates while small ones were obtained using Sr(NO3)2 as templates. It is found that titanium precursor plays an important role for the morphology of samples. Solid TiO2 microspheres were prepared by using titanium tetrabutoxide (TBT). In contrast, bowl-like hollow microspheres were obtained by using titanium tetrachloride (TiCl4). Furthermore, the amount of H2O can stimulate the hydrolysis rate of TiCl4 to form solid spheres. Compared with solid microspheres, hollow TiO2 microspheres depending on their interior cavity structure exhibited enhanced photocatalysis efficiency for the UV-light photodegradation of methyl orange. Quantificationally, the apparent photocatalytic degradation pseudo-first-rate constant of the hollow microspheres is 1.25 times of that of the solid ones.

  8. Symmetry breaking polymerization: one-pot synthesis of plasmonic hybrid Janus nanoparticles.

    PubMed

    Wang, Yanming; Ding, Tao; Baumberg, Jeremy J; Smoukov, Stoyan K

    2015-06-21

    Asymmetric hybrid nanoparticles have many important applications in catalysis, nanomotion, sensing, and diagnosis, however ways to generate the asymmetric hybrid nanoparticles are quite limited and inefficient. Most current methods rely on interfacial adhesion and modification of already formed particles. In this article we report a one-pot, facile and scalable synthesis of anisotropic Au-polymer hybrid nanoparticles via interfacial oxidative dispersion polymerization. The interfacial nucleation and polymerization lead to spontaneous symmetry breaking and formation of the Janus particles. The reaction is initiated by monomer radicals generated by the strong oxidant HAuCl4, which is itself later reduced by the electron-rich monomers to self-nucleate and form Au nanoparticles (NPs). The competition between divinylbenzene adsorption and the PVP capping agent results in effective partial surface wetting, forming asymmetric Au-PDVB hybrid nanoparticles, by confining growth of each material to its own phase. Such spontaneous symmetry breaking, important in morphogenesis, with control over the subsequent growth processes should lead to significant advances in the synthesis of asymmetric nanostructures. PMID:26000977

  9. One-pot synthesis of platinum3cobalt nanoflowers with enhanced oxygen reduction and methanol oxidation

    NASA Astrophysics Data System (ADS)

    Zheng, Jie-Ning; He, Li-Li; Chen, Chen; Wang, Ai-Jun; Ma, Ke-Fu; Feng, Jiu-Ju

    2014-12-01

    Herein, a simple one-pot approach is developed for preparation of Pt3Co nanoflowers by co-reduction of Pt (II) acetylacetonate (Pt(acac)2) and Co (III) acetylacetonate (Co(acac)3) in oleylamine, without any seed or template. It is found that hexadecylpyridinium chloride monohydrate (HDPC) is served as both the stabilizing and structuring-directing agent that plays an important role in the formation of well-dispersed flower-like Pt3Co nanoparticles. The as-prepared Pt3Co nanoflowers show the enhanced catalytic performance for oxygen reduction reaction (ORR) in comparison with solid Pt3Co nanoparticles and commercial Pt black catalysts, dominated by a four-electron pathway based on the Koutecky-Levich equation. Meanwhile, Pt3Co nanoflowers exhibit the improved catalytic activity and long-term stability towards methanol oxidation reaction (MOR), using solid Pt3Co nanoparticles and commercial Pt black catalysts as references. The improved catalytic features of Pt3Co nanoflowers are mainly attributed to the porous three-dimensionally interconnected structures, enlarged specific surface area, ligand effect and bifunctional mechanism between Pt and Co. The as-developed method provides a promising pathway for preparation of highly efficient electrocatalysts for ORR and MOR.

  10. Facile and efficient one-pot synthesis of benzimidazoles using lanthanum chloride

    PubMed Central

    2013-01-01

    Background We report the synthesis of benzimidazoles using lanthanum chloride as an efficient catalyst. One-pot synthesis of 2-substituted benzimidazole derivatives from o-phenylenediamine and a variety of aldehydes were developed under mild reaction conditions. Results We have examined the effect of different solvents using the same reaction conditions. The yield of the product varied with the nature of the solvents, and better conversion and easy isolation of products were found with acetonitrile. In a similar manner, the reaction with o-phenylenediamine and 3,4,5-trimethoxybenzaldehyde was carried out without any solvents. The observation shows that the reaction was not brought into completion, even after starting for a period of 9 h, and the reaction mixture showed a number of spots in thin-layer chromatography. Conclusions In conclusion, lanthanum chloride has been employed as a novel and efficient catalyst for the synthesis of benzimidazoles in good yields from o-phenylenediamine and a wide variety of aldehydes. All of the reactions were carried out in the presence of lanthanum chloride (10 mol%) in acetonitrile at room temperature. PMID:23919542

  11. Preparing hydrophobic nanocellulose-silica film by a facile one-pot method.

    PubMed

    Le, Duy; Kongparakul, Suwadee; Samart, Chanatip; Phanthong, Patchiya; Karnjanakom, Surachai; Abudula, Abuliti; Guan, Guoqing

    2016-11-20

    Hydrophobic nanocellulose-silica film was successfully prepared by a facile one-pot method using tetraethoxysilane (TEOS) and dodecyl triethoxylsilane (DTES). Morphological characterization of the hydrophobic nanocellulose-silica (NC-SiO2-DTES) film showed well self-assembled DTES modified silica spherical nanoparticles with the particle sizes in the range of 88-126nm over the nanocellulose film. The hydrophobicity of the NC-SiO2-DTES film was achieved owing to the improvement of roughness of the nanocellulose film by coating dodecyl- terminated silica nanoparticles. An increase in DTES loading amount and reaction time increased the hydrophobicity of the film, and the optimum condition for NC-SiO2-DTES film preparation was achieved at DTES/TEOS molar ratio of 2.0 for 8h reaction time. Besides, the NC-SiO2-DTES film performed superoleophilic property with octane and hexadecane contact angles of 0°. It also showed an excellent hydrophobic property over all pH values ranged from 1 to 14. PMID:27561496

  12. One pot synthesis of intriguing fluorescent carbon dots for sensing and live cell imaging.

    PubMed

    Jana, Jayasmita; Ganguly, Mainak; Das, Bodhisatwa; Dhara, Santanu; Negishi, Yuichi; Pal, Tarasankar

    2016-04-01

    We report a simple one-pot synthesis of highly fluorescent carbon dots (CDs) via modified hydrothermal (MHT) treatment of alkaline solution of dopamine and cysteine. These CDs (λex=320 nm, λem=390 nm, and quantum yield ∼ 5.1%) are of ∼ 2-3 nm in diameter. Further attempt of synthesizing CDs in some common water-miscible solvents ends up the fact that the MHT product from acetone medium is nonfluorescent. However, CDs, produced in aqueous medium, are so stable that they can be dried as a deliverable solid (WCD) without any alteration of fluorescing property if reversibly dispersed in water. Fluorescence of WCD is quenched selectively in acetone. Quenching occurs presumably due to the disruption of radiative recombination along with the hindrance in quantum confinement of the emissive energy traps to the particle surface. Successive quenching of fluorescence of WCD in different acetone concentration admixed in water paves the way to selective acetone sensing (LOD=8.75 × 10(-7) M). The synthesized CDs (in aqueous medium) are cytocompatible and are efficient fluorescent probe for cell imaging. Only living cells are recognized exclusively from fluorescence imaging leaving aside dead cells, while cells are treated with CDs. PMID:26838406

  13. One pot synthesis of opposing 'rose petal' and 'lotus leaf' superhydrophobic materials with zinc oxide nanorods.

    PubMed

    Myint, Myo Tay Zar; Hornyak, Gabor L; Dutta, Joydeep

    2014-02-01

    The synthesis in one pot(1) of opposing 'rose petal' and 'lotus leaf' superhydrophobic materials from commercially available superhydrophilic cloth substrates of varying texture is described for the first time. Surfaces of 'rough' textured cloth and 'smooth' textured cloth were simultaneously rendered superhydrophobic by growing zinc oxide (ZnO) nanorods by a hydrothermal process in the same chemical bath. Contact angle hysteresis and water pendant drop tests revealed strong water adhesion to ZnO microrod-treated rough cloth. The combination of water contact angle >150° and strong adhesion is indicative of the 'rose petal effect' with potential for water pinning. Smooth cloth with ZnO nanorods exhibited no adhesion to water droplets with facilitative roll-off. The combination of water contact angle >150° and weak to no adhesion with water is indicative of the 'lotus leaf effect' with potential for self-cleaning. Pendant water drop tests indicated cohesive failure of water on rough cloth coated with ZnO nanorods. Natural rose petals demonstrated adhesive failure between the petal surface and water droplet. A parsimonious explanation is presented. We also describe the development of superhydrophobic clothes without the need for special conditions or further chemical modification. PMID:24267327

  14. Efficient production of biodiesel from waste grease: one-pot esterification and transesterification with tandem lipases.

    PubMed

    Yan, Jinyong; Li, Aitao; Xu, Yi; Ngo, Thao P N; Phua, Szechao; Li, Zhi

    2012-11-01

    A novel concept and efficient method for producing biodiesel (FAME) from grease (15-40wt% free fatty acid, FFA) were developed by using tandem lipases for one-pot esterification of FFA and transesterification of triglyceride with methanol in a solvent-free system. Combining immobilized Candida antarctica lipase B (CALB) (Novozyme 435) favoring the esterification and immobilized Thermomyces lanuginosus lipase (TLL) (Lipozyme TLIM) preferring the transesterification at 2:8 (wt/wt) gave FAME in 80% yield, being better than that with Novozyme 435 or Lipozyme TLIM. Recombinant Escherichia coli (Calb/Tll) co-expressing CALB and TLL was engineered as a more efficient tandem-lipases system. Using wet or dry cells (4wt%) gave FAME in 87% or 95% yield, which is much better than that with E. coli cells expressing either CALB or TLL alone. Cells of E. coli (Calb/Tll) were recycled for five times and retained 75% productivity, thus being practical for producing biodiesel from grease. PMID:22940338

  15. One-pot synthesis of hierarchical MnO2-modified diatomites for electrochemical capacitor electrodes

    NASA Astrophysics Data System (ADS)

    Zhang, Yu Xin; Huang, Ming; Li, Fei; Wang, Xue Li; Wen, Zhong Quan

    2014-01-01

    The hierarchical and porous MnO2-modified diatomite structures are prepared for the first time by a one-pot hydrothermal method. The morphology and structure of MnO2-modified diatomite hierarchical structures are examined by focus ion beam scanning electron microscopy (FIB/SEM) and X-ray diffraction spectroscopy (XRD). The results show that Birnessite-type MnO2 nanosheets are observed to grow vertically on the purified diatomite, thus building hierarchical architecture. Furthermore, the electrochemical properties of the MnO2-modified diatomite electrodes are elucidated by cyclic voltammograms, galvanostatic charge/discharge tests and electrochemical impedance spectroscopy in 1 M Na2SO4 electrolyte. The electrochemical results demonstrate that the MnO2-modified diatomite electrode exhibits highly reversible features and good rate abilities, respectively. Significantly, it exhibits the specific capacitance of 202.6 F g-1 for the MnO2-modified diatomite and 297.8 F g-1 for the MnO2 nanostructures after etching the diatomite. The capacitance retention of 95.92% over 5000 cycles further indicates the suitability of the low-cost MnO2-modified diatomite structure as a potential electrode material for supercapacitors.

  16. One-pot synthesis of magnetic, macro/mesoporous bioactive glasses for bone tissue engineering

    NASA Astrophysics Data System (ADS)

    Wang, Dan; Lin, Huiming; Jiang, Jingjie; Han, Xiao; Guo, Wei; Wu, Xiaodan; Jin, Yingxue; Qu, Fengyu

    2013-04-01

    Magnetic and macro/mesoporous bioactive glasses were synthesized by a one-pot method via a handy salt leaching technique. It was identified to be an effective and simple synthetic strategy. The non-ionic triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123), was used as the structure directing agent for mesoporous structure but also as the reductant to reduce the iron source into magnetic iron oxide. The prepared materials exhibited excellent super-paramagnetic property with interconnected macroporous (200-300 μm) and mesoporous (3.4 nm) structure. Furthermore, their outstanding drug storage/release properties and rapid (5) induction of hydroxyapatite growth ability were investigated after immersing in simulated body fluid solution at 37 °C. Notably, the biocompatibility assessment confirmed that the materials obtained presented good biocompatibility and enhanced adherence of HeLa cells. Herein, the novel materials are expected to have potential application for bone tissue engineering.

  17. One-pot synthesis of aptamer-functionalized silver nanoclusters for cell-type-specific imaging.

    PubMed

    Li, Jingjing; Zhong, Xiaoqin; Cheng, Fangfang; Zhang, Jian-Rong; Jiang, Li-Ping; Zhu, Jun-Jie

    2012-05-01

    As an emerging category of fluorescent metal nanoclusters, oligonucleotide-templated silver nanoclusters (Ag NCs) have attracted a lot of interest and have shown wide application in biorelated disciplines. However, the weak fluorescence emission and poor permeability to cell membranes tethered further intracellular applications of Ag NCs. AS1411 is an antiproliferative G-rich phosphodiester oligonucleotide and currently an anticancer agent under phase II clinical trials. Herein, we present a strategy to synthesize AS1411-functionalized Ag NCs with excellent fluorescence through a facile one-pot process. Confocal laser scanning microscopy and Z-axis scanning confirmed that the AS1411-functionalized Ag NCs could be internalized into MCF-7 human breast cancer cells and were able to specifically stain nuclei with red color. To our surprise, 3-[4,5-dimethylthiazol-z-yl]-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated the Ag NCs were cytocompatible and showed better inhibition effects than pure AS1411 on MCF-7 human breast cancer cells. In addition, a universal design of the oligonucleotide scaffold for synthesis of Ag NCs was extended to other aptamers, such as Sgc8c and mucin 1 aptamer. Due to the facile synthesis procedure and capability of specific target recognition, this fluorescent platform will potentially broaden the applications of Ag NCs in biosensing and biological imaging. PMID:22482827

  18. One-pot, bioinspired coatings to reduce the flammability of flexible polyurethane foams.

    PubMed

    Davis, Rick; Li, Yu-Chin; Gervasio, Michelle; Luu, Jason; Kim, Yeon Seok

    2015-03-25

    In this manuscript, natural materials were combined into a single "pot" to produce flexible, highly fire resistant, and bioinspired coatings on flexible polyurethane foam (PUF). In one step, PUF was coated with a fire protective layer constructed of a polysaccharide binder (starch or agar), a boron fire retardant (boric acid or derivative), and a dirt char former (montmorillonite clay). Nearly all coatings produced a 63% reduction in a critical flammability value, the peak heat release rate (PHRR). One formulation produced a 75% reduction in PHRR. This technology was validated in full-scale furniture fire tests, where a 75% reduction in PHRR was measured. At these PHRR values, this technology could reduce the fire threat of furniture from significant fire damage in and beyond the room of fire origin to being contained to the burning furniture. This flammability reduction was caused by three mechanisms-the gas-phase and condensed-phase processes of the boron fire retardant and the condensed-phase process of the clay. We describe the one-pot coating process and the impact of the coating composition on flammability. PMID:25723711

  19. One-pot hydrothermal synthesis of orange fluorescent silver nanoclusters as a general probe for sulfides.

    PubMed

    Lan, Jing; Zhang, Pu; Wang, Ting Ting; Chang, Yong; Lie, Shao Qing; Wu, Zhu Lian; Liu, Zhong De; Li, Yuan Fang; Huang, Cheng Zhi

    2014-07-01

    Water-soluble fluorescent silver nanoclusters (AgNCs) with almost seven and nine silver atoms and a quantum yield (QY) of 5.38 ± 0.25% were successfully prepared via one-pot hydrothermal synthesis using polymethacrylic acid sodium salt (PMAA-Na) as a template. The as-prepared PMAA-AgNCs displayed a mono-distribution, they were uniform in size and the color of the fluorescence, emitting at 579 nm, was orange when excited at 502 nm. What is more, we found that the as-prepared PMAA-AgNCs could be quenched by sulfides based on the formation of a metal-ligand bond Ag-S, and thus sulfides could be sensitively detected by spectrofluorometry. As proof of concept, thiourea (TU) and other sulfides including cysteine (Cys), glutathione (GSH) and dl-methionine could be detected. For example, the color of the orange fluorescent AgNCs solutions darkened upon the addition of TU and the fluorescence of PMAA-AgNCs was quenched. The detection limit for TU was 6.10 μM in the linear range from 8.57 μM to 2.29 mM. PMID:24834451

  20. One-pot pseudomorphic crystallization of mesoporous porous silica to hierarchical porous zeolites

    SciTech Connect

    Xing, Jun-Ling; Jiang, Shu-Hua; Pang, Jun-Ling; Yuan, En-Hui; Ma, Xiao-Jing; Lam, Koon-Fung; Xue, Qing-Song; Zhang, Kun

    2015-09-15

    Hierarchically porous silica with mesopore and zeolitic micropore was synthesized via pseudomorphic crystallization under high-temperature hydrothermal treatment in the presence of cetyltrimethylammonium tosylate and tetrapropylammonium ions. A combined characterization using small-angle X-ray diffraction (XRD), nitrogen adsorption, high-resolution transmission electron microscopy (TEM), thermogravimetric analysis (TG), and elemental analysis showed that dual templates, CTA{sup +} and TPA{sup +} molecules, can work in a cooperative manner to synthesize mesoporous zeolite in a one-pot system by precisely tuning the reaction conditions, such as reaction time and temperature, and type and amount of heterometal atoms. It is found that the presence of Ti precursor is critical to the successful synthesis of such nanostructure. It not only retards the nucleation and growth of crystalline MFI domains, but also acts as nano-binder or nano-glue to favor the assembly of zeolite nanoblocks. - Graphical abstract: Display Omitted - Highlights: • A facile method to synthesize mesoporous zeolites with hierarchical porosity was presented. • It gives a new insight into keeping the balance between mesoscopic and molecular ordering in hierarchical porous materials. • A new understanding on the solid–solid transformation mechanism for the synthesis of titanosilicate zeolites was proposed.

  1. Rapid approach to biobased telechelics through two one-pot thiol-ene click reactions.

    PubMed

    Lluch, Cristina; Ronda, Joan C; Galià, Marina; Lligadas, Gerard; Cádiz, Virginia

    2010-06-14

    The application of environmentally friendly thiol-ene chemistry to the preparation of biobased telechelics is presented in this work. This methodology is based on two one-pot photoinitiated thiol-ene click processes: step-growth polymerization using a 3,6-dioxa-1,8-octanedithiol and end-group postpolymerization modification with three functional thiols: 2-mercaptoethanol, 3-mercaptopropionic acid, and 3-mercaptopropyltrimethoxysilane. We applied this approach to a potentially 100% biomass-derived monomer, allyl ester of 10-undecenoic acid (UDA). To show the generality and scope of this methodology, a series of well-defined telechelics with molecular weight ranging from 1000-3000 g/mol and hydroxyl, carboxyl, or trimethoxysilyl groups at the polymer terminus were prepared. An exhaustive (1)H NMR and MALDI-TOF MS analyses demonstrates the highly end-group fidelity of this methodology being an interesting procedure for the accelerated preparation of telechelics derived from divinyl monomers. UDA-based thelechelic diol prepared using this methodology was reacted with 4,4'-methylenebis(phenylisocyanate) and 1,4-butanediol as the chain extender to obtain multiblock poly(ester urethane). PMID:20462176

  2. One-pot synthesis and physicochemical properties of an organo-modified saponite clay.

    PubMed

    Bisio, Chiara; Carniato, Fabio; Paul, Geo; Gatti, Giorgio; Boccaleri, Enrico; Marchese, Leonardo

    2011-06-01

    An organo-saponite clay containing intercalated cetyltrimethylammonium (CTA(+)) cations was synthesized by an efficient one-step hydrothermal method and was compared with a CTA-exchanged saponite prepared by a classical postsynthesis intercalation route. In both hybrid samples, surfactant loading up to 10% was achieved. A comparative investigation of the physicochemical properties of both solids was carried out by a multidisciplinary approach, by using a combination of spectroscopic, structural, and thermal characterization tools. Powder X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) data indicated that the one-pot-prepared solid showed that the presence of CTA(+) molecules in the synthesis gel did not affect the clay structure. In addition, thermal analysis suggested that the inorganic layers play an active role in stabilizing and protecting the surfactant molecules by increasing their thermal stability. A different arrangement of intercalated CTA(+) ions in the two hybrid clays was observed by solid state NMR in combination with Fourier transform infrared (FTIR) spectroscopy and assigned to a different all-trans/gauche conformation ratio of the surfactant depending on the synthetic method used to prepare the two final materials. The surfactant organization is also influenced by the lamellae charge density, which is different in the two organo-modified materials as found by (27)Al and (29)Si MAS NMR experiments. PMID:21553926

  3. A one-pot strategy for biomimetic synthesis and self-assembly of gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Wang, Yi; Chen, Li Qiang; Li, Yuan Fang; Zhao, Xi Juan; Peng, Li; Zhi Huang, Cheng

    2010-07-01

    A simple, one-pot and controllable strategy is reported in this contribution for biomimetic synthesis and self-assembly of gold nanoparticles (Au-NPs). It involves our synthesized polyaldehyde dextran (PAD), which has been proved to be a biomacromolecule with excellent biocompatibility and biodegradability, acting as both a reducing agent and a stabilizer. The morphology of the as-prepared Au-NP assemblies can be controlled by adjusting the reaction conditions, such as the concentration of aldehyde in PAD, the reaction time and the temperature. Investigations of the mechanism suggest that stabilizers may distribute on different crystal facets of NPs non-uniformly owing to the different binding forces, and dipole-dipole interaction of NPs could be the main driving force for the assembly of Au-NPs. In addition, intermolecular hydrogen bonding interaction of stabilizers could also act as a possible driving force. The excellent biocompatibility of the Au-NP assemblies makes them promising candidates for fabricating future optical nanodevices and application in biological systems.

  4. One pot electrochemical synthesis of polymer/CNT/metal nanoparticles for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Ventrapragada, Lakshman; Zhu, Jingyi; Karakaya, Mehmet; Podila, Ramakrishna; Rao, Apparao; Clemson Nanomaterials center Team

    Carbon nanotubes (CNTs) have become a key player in the design of materials for energy applications. They gained their popularity in industrial and scientific research due to their unique properties like excellent conductivity, high surface area, etc. Here we used chemical vapor deposition (CVD) to synthesize two types of CNTs namely, helically coiled CNTs and vertically aligned CNTs. These CNTs were subsequently used to make composites with conducting polymers and metal nanoparticles. One pot electrochemical synthesis was designed to electropolymerize aniline, pyrrole etc. on the surface of the electrode with simultaneous deposition of platinum and gold metal nanoparticles, and CNTs in the polymer matrix. The as synthesized composite materials were characterized with scanning electron microscope for surface morphology and spectroscopic techniques like Raman, UV-Vis for functionality. These were used to study electrocatalytic oxidation of methanol and ethanol for alkaline fuel cell applications. Electrodes fabricated from these composites not only showed good kinetics but also exhibited excellent stability. Uniqueness of this composite lies in its simple two step synthesis and it doesn't involve any surfactants unlike conventional chemical synthesis routes.

  5. A novel one-pot route for large-scale preparation of highly photoluminescent carbon quantum dots powders

    NASA Astrophysics Data System (ADS)

    Hou, Juan; Yan, Jin; Zhao, Qi; Li, Yi; Ding, Hong; Ding, Lan

    2013-09-01

    A simple one-pot microwave-assisted approach has been established for the large-scale preparation of carbon quantum dots (CDs) with excellent water solubility and photoluminescence. The properties and mechanism were demonstrated. Moreover, the CDs have been applied to the detection of tetracycline hydrochloride.A simple one-pot microwave-assisted approach has been established for the large-scale preparation of carbon quantum dots (CDs) with excellent water solubility and photoluminescence. The properties and mechanism were demonstrated. Moreover, the CDs have been applied to the detection of tetracycline hydrochloride. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03444e

  6. Asymmetric One-Pot Synthesis of 1,3-Oxazolidines and 1,3-Oxazinanes via Hemiaminal Intermediates

    PubMed Central

    2015-01-01

    A highly efficient method for the enantioselective one-pot synthesis of 1,3-oxazolidines and 1,3-oxazinanes has been reported. The reaction proceeds via the formation of hemiaminal intermediates obtained by the enantioselective addition of respective alcohols to imines catalyzed by a chiral magnesium phosphate catalyst, followed by intramolecular cyclization under mildly basic conditions. A wide range of substrates have been converted to the respective chiral heterocyclic products in high yields and with excellent enantioselectivities using this one-pot procedure. PMID:25075467

  7. One-pot synthesis of S-alkyl dithiocarbamates via the reaction of N-tosylhydrazones, carbon disulfide and amines.

    PubMed

    Sha, Qiang; Wei, Yun-Yang

    2013-09-14

    A new, convenient and efficient transition metal-free synthesis of S-alkyl dithiocarbamates through one-pot reaction of N-tosylhydrazones, carbon disulfide and amines is reported. Tosylhydrazones derived from various aromatic and aliphatic ketones or aldehydes were tested and gave dithiocarbamates in good to excellent yields. The tosylhydrazones can be generated in situ without isolation, which provides a simpler one-pot method to synthesize dithiocarbamates via the reaction of carbonyl compounds, carbon disulfide and amines in the presence of 4-methylbenzenesulfonohydrazide. PMID:23863979

  8. One-pot synthesis of reduced graphene oxide-cadmium sulfide nanocomposite and its photocatalytic hydrogen production.

    PubMed

    Zeng, Peng; Zhang, Qinggang; Peng, Tianyou; Zhang, Xiaohu

    2011-12-28

    Reduced graphene oxide (RGO)-cadmium sulfide (CdS) nanocomposites were successfully prepared by a one-pot solvothermal process without pretreatment of graphene oxide (GO) and a precipitation process, in which GO needs to be pre-reduced by hydrazine. The as-obtained RGO-CdS nanocomposites were used as photocatalysts for hydrogen production under visible light irradiation, and it was found that the product derived from the one-pot solvothermal process showed much better photoactivity than that from the precipitation method. PMID:22068902

  9. One-pot formation of multifunctional Pt-conducting polymer intercalated nanostructures

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Lu, Ning; Poyraz, Selcuk; Wang, Xiaolong; Yu, Yajiao; Scott, Julie; Smith, James; Kim, Moon J.; Zhang, Xinyu

    2013-04-01

    A novel multifunctional Pt nanoparticle@PPy nanofiber intercalated structure (Pt NP@PPy NF) has been synthesized facilely in one-pot. Pt NPs, with size and facet control, were nicely assembled and embedded into the polymer nanofiber network. Polyvinylpyrrolidone (PVP) was used during the synthesis process which would assist the self-assembly of the metal nanoparticles and polymer backbones into the intercalated structure. Space-confined distribution of the Pt NPs was achieved within the large dimension PPy nanofiber network, which could enhance the interfacial electron transfer process as well as diminish the catalyst deformation. The as-formed Pt NPs have a cluster-like structure and are mainly composed of 3.5 nm primary Pt particles with (100) surface atoms. Enhanced electrocatalytic properties were shown by the Pt NP@PPy NF intercalated structure, with sufficiently high enzyme-less glucose biosensitivity and a long linear range from 1-30 mM (R = 0.9995). High electrochemical cycling stability, chloride (Cl-) tolerance and good selectivity are also obtained for the Pt NP@PPy NF structure, as the electrode showed no obvious response to the common interfering agents, such as ascorbic acid (AA), uric acid (UA), and 4-acetamidophenol (AP). Furthermore, the Pt NP@PPy NF showed excellent catalytic activity for the methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR), which displayed sufficient CO tolerance, and higher activity compared to the commercial Pt/C catalyst. This intrinsically multifunctional Pt NP@PPy NF with well-controlled Pt facets thus could serve as an advanced electrocatalyst for biosensing and fuel cell applications, surpassing the performance of many existing materials.A novel multifunctional Pt nanoparticle@PPy nanofiber intercalated structure (Pt NP@PPy NF) has been synthesized facilely in one-pot. Pt NPs, with size and facet control, were nicely assembled and embedded into the polymer nanofiber network. Polyvinylpyrrolidone (PVP

  10. One-pot conversion of cellulose to ethylene glycol with multifunctional tungsten-based catalysts.

    PubMed

    Wang, Aiqin; Zhang, Tao

    2013-07-16

    With diminishing fossil resources and increasing concerns about environmental issues, searching for alternative fuels has gained interest in recent years. Cellulose, as the most abundant nonfood biomass on earth, is a promising renewable feedstock for production of fuels and chemicals. In principle, the ample hydroxyl groups in the structure of cellulose make it an ideal feedstock for the production of industrially important polyols such as ethylene glycol (EG), according to the atom economy rule. However, effectively depolymerizing cellulose under mild conditions presents a challenge, due to the intra- and intermolecular hydrogen bonding network. In addition, control of product selectivity is complicated by the thermal instabilities of cellulose-derived sugars. A one-pot catalytic process that combines hydrolysis of cellulose and hydrogenation/hydrogenolysis of cellulose-derived sugars proves to be an efficient way toward the selective production of polyols from cellulose. In this Account, we describe our efforts toward the one-pot catalytic conversion of cellulose to EG, a typical petroleum-dependent bulk chemical widely applied in the polyester industry whose annual consumption reaches about 20 million metric tons. This reaction opens a novel route for the sustainable production of bulk chemicals from biomass and will greatly decrease the dependence on petroleum resources and the associated CO₂ emission. It has attracted much attention from both industrial and academic societies since we first described the reaction in 2008. The mechanism involves a cascade reaction. First, acid catalyzes the hydrolysis of cellulose to water-soluble oligosaccharides and glucose (R1). Then, oligosaccharides and glucose undergo C-C bond cleavage to form glycolaldehyde with catalysis of tungsten species (R2). Finally, hydrogenation of glycolaldehyde by a transition metal catalyst produces the end product EG (R3). Due to the instabilities of glycolaldehyde and cellulose

  11. One-pot formation of multifunctional Pt-conducting polymer intercalated nanostructures.

    PubMed

    Liu, Yang; Lu, Ning; Poyraz, Selcuk; Wang, Xiaolong; Yu, Yajiao; Scott, Julie; Smith, James; Kim, Moon J; Zhang, Xinyu

    2013-05-01

    A novel multifunctional Pt nanoparticle@PPy nanofiber intercalated structure (Pt NP@PPy NF) has been synthesized facilely in one-pot. Pt NPs, with size and facet control, were nicely assembled and embedded into the polymer nanofiber network. Polyvinylpyrrolidone (PVP) was used during the synthesis process which would assist the self-assembly of the metal nanoparticles and polymer backbones into the intercalated structure. Space-confined distribution of the Pt NPs was achieved within the large dimension PPy nanofiber network, which could enhance the interfacial electron transfer process as well as diminish the catalyst deformation. The as-formed Pt NPs have a cluster-like structure and are mainly composed of 3.5 nm primary Pt particles with (100) surface atoms. Enhanced electrocatalytic properties were shown by the Pt NP@PPy NF intercalated structure, with sufficiently high enzyme-less glucose biosensitivity and a long linear range from 1-30 mM (R = 0.9995). High electrochemical cycling stability, chloride (Cl(-)) tolerance and good selectivity are also obtained for the Pt NP@PPy NF structure, as the electrode showed no obvious response to the common interfering agents, such as ascorbic acid (AA), uric acid (UA), and 4-acetamidophenol (AP). Furthermore, the Pt NP@PPy NF showed excellent catalytic activity for the methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR), which displayed sufficient CO tolerance, and higher activity compared to the commercial Pt/C catalyst. This intrinsically multifunctional Pt NP@PPy NF with well-controlled Pt facets thus could serve as an advanced electrocatalyst for biosensing and fuel cell applications, surpassing the performance of many existing materials. PMID:23525158

  12. One-pot synthesis of two-sized clusters for ratiometric sensing of Hg2+.

    PubMed

    Chen, Tzu-Heng; Lu, Chi-Yu; Tseng, Wei-Lung

    2013-12-15

    This paper presents a discussion of a one-pot approach for preparing lyszoyme type VI (Lys VI) stabilized clusters, including small (Au7Ag and Au8) and large (Au24Ag) clusters, for ratiometric fluorescence sensing of Hg(2+). Our previous study (Chen and Tseng, Small 8 (2012) 1912) showed the formation of intermediate Au8 clusters in the conversion of Au(+)-Lys VI protein complexes to Au25 clusters. The presence of Ag(+) in the precursor solution slowed this conversion, thereby forming two-sized clusters. With an increase in Ag(+) content, a systematic blue shift in the first exciton absorption and fluorescence peaks indicated the formation of Au-Ag bimetallic clusters. The prepared Ag(+)/Au(3+) molar ratio of 2:8 resulted in the formation of two-sized clusters, with dual emission bands centered at 471 and 613 nm. After these clusters are separated by a membrane filter, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to determine the composition of Au24Ag clusters. By monitoring the intensity ratio of the two emission wavelengths, the solution consisting of Hg(2+)-insensitive small clusters (Au7Ag and Au8) and Hg(2+)-sensitive Au24Ag clusters exhibited a ratiometric fluorescence response toward Hg(2+), and provided a built-in correction for photobleaching; the limit of detection at a signal-to-noise ratio of three for Hg(2+) was estimated to be 1 nM. This probe was successfully applied to ratiometric fluorescence sensing of Hg(2+) in tap water. PMID:24209338

  13. A facile one-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica: Aqueous hydration of nitriles to amides

    EPA Science Inventory

    One-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica is described which involve the in situ generation of magnetic silica (Fe3O4@ SiO2) and ruthenium hydroxide immobilization; the hydration of nitriles occurs in high yield and excellent selectivity using this...

  14. One-Pot Asymmetric Nitro-Mannich/Hydroamination Cascades for the Synthesis of Pyrrolidine Derivatives: Combining Organocatalysis and Gold Catalysis

    PubMed Central

    2014-01-01

    The highly enantioselective preparation of trisubstituted pyrrolidine derivatives employing a one-pot nitro-Mannich/hydroamination cascade is reported. This cascade approach utilizes an asymmetric bifunctional organocatalytic nitro-Mannich reaction followed by a gold-catalyzed allene hydroamination reaction. The products are afforded in good yields and excellent diastereo- and enantioselectivities. PMID:24563809

  15. Metal-free one-pot synthesis of 2-substituted and 2,3-disubstituted morpholines from aziridines

    PubMed Central

    Sun, Hongnan; Huang, Binbin; Lin, Run; Yang, Chao

    2015-01-01

    Summary The metal-free synthesis of 2-substituted and 2,3-disubstituted morpholines through a one-pot strategy is described. A simple and inexpensive ammonium persulfate salt enables the reaction of aziridines with halogenated alcohols to proceed via an SN2-type ring opening followed by cyclization of the resulting haloalkoxy amine. PMID:25977727

  16. Metal-free one-pot synthesis of 2-substituted and 2,3-disubstituted morpholines from aziridines.

    PubMed

    Sun, Hongnan; Huang, Binbin; Lin, Run; Yang, Chao; Xia, Wujiong

    2015-01-01

    The metal-free synthesis of 2-substituted and 2,3-disubstituted morpholines through a one-pot strategy is described. A simple and inexpensive ammonium persulfate salt enables the reaction of aziridines with halogenated alcohols to proceed via an SN2-type ring opening followed by cyclization of the resulting haloalkoxy amine. PMID:25977727

  17. Synthesis of Quaternary Ammonium Salts of Tricyclic Cationic Drugs: A One-Pot Synthesis for the Bioorganic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Brunauer, Linda S.; Mogannam, Abid C.; Hwee, Won B.; Chen, James Y.

    2007-01-01

    A one-pot conversion of tricyclic cationic drugs to their quaternary ammonium forms is described for a widely used bioactive drug: chlorpromazine, a phenothiazine-based antipsychotic. After conversion to its free base, the parent drug was methylated using substoichiometric amounts of methyl iodide dissolved in ether; the charged quaternary…

  18. A facile one pot strategy for the synthesis of well-defined polyacrylates from acrylic acid via RAFT polymerization.

    PubMed

    Li, Qianbiao; Wang, Taisheng; Dai, Jingwen; Ma, Chao; Jin, Bangkun; Bai, Ruke

    2014-03-28

    A facile one pot strategy for the preparation of linear and hyperbranched polyacrylates has been successfully developed by the combination of in situ esterification of acrylic acid with halogenated compounds promoted by 1,1,3,3-tetramethylguanidine (TMG) and RAFT polymerization. PMID:24534953

  19. One-pot simultaneous saccharification and fermentation: a preliminary study of a novel configuration for cellulosic ethanol production.

    PubMed

    Li, Jingbo; Lin, Jianghai; Zhou, Pengfei; Wu, Kejing; Liu, Hongmei; Xiong, Chunjiang; Gong, Yingxue; Xiao, Wenjuan; Liu, Zehuan

    2014-06-01

    Combination of size reduction and mild alkali pretreatment may be a feasible way to produce bioethanol without rinsing and detoxifying the solid substrate. Based on that, a fermentation configuration named one-pot SSF in which pretreatment and fermentation steps were integrated was developed. Additionally, the effect of laccase on fermentation performance was investigated. Delignification was the major effect of the alkali pretreatment at 121°C for 60min. The highest glucose and xylose yield, which obtained from the smallest particle at a substrate loading of 2%, was 6.75 and 2.71g/L, respectively. Laccase improved the fermentation efficiency by 6.8% for one-pot SSF and 5.7% for SSF. Bioethanol from one-pot SSF with laccase supplementation reached 67.56% of the theoretical maximum, whereas that from SSF with laccase supplementation reached 57.27%. One-pot SSF might be a promising configuration to produce bioethanol because of 100% solid recovery, and rinsing water and detoxification elimination. PMID:24704838

  20. One-pot preparation of unsaturated polyester nanocomposites containing functionalized graphene sheets via a novel solvent-exchange method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reports a convenient one-pot method integrating a novel solvent-exchange method into in situ melt polycondensation to fabricate unsaturated polyester nanocomposites containing functionalized graphene sheets (FGS). A novel solvent-exchange method was first developed to prepare graphene oxi...

  1. One-Pot Catalyst-Free Synthesis of β- and γ-Hydroxy Sulfides using Diaryliodonium Salts and Microwave Irradiation

    EPA Science Inventory

    A facile one-pot high-yield protocol is described for the preparation of β- and γ-hydroxy sulfides directly from diaryliodonium salts, potassium thiocyanate, and ethane-1,2-diol (ethylene glycol)/propane-1,3-diol (β-propylene glycol) without the need for any additional catalyst o...

  2. One-pot Catalyst-free Synthesis of β- and γ-Hydroxy Sulfides Using Diaryliodonium Salts and Microwaves

    EPA Science Inventory

    A facile one-pot high-yield protocol is described for the preparation of β- and γ-hydroxy sulfides directly from diaryliodonium salts, potassium thiocyanate, and ethane-1,2-diol (ethylene glycol)/propane-1,3-diol (β-propylene glycol) without the need for any addit...

  3. One-pot atom-efficient synthesis of bio-renewable polyesters and cyclic carbonates through tandem catalysis.

    PubMed

    Jia, Fan; Chen, Xiaoyu; Zheng, Yan; Qin, Yusheng; Tao, Youhua; Wang, Xianhong

    2015-05-18

    One-pot synthesis of well-defined bio-renewable polyesters and cyclic carbonates in high yields was successfully realized for the first time by way of a tandem reaction using metal salen complexes as catalysts. This tandem process offered unprecedented opportunities for the atom-efficient production of two relevant compounds. PMID:25892206

  4. Highly efficient one-pot three-component synthesis of naphthopyran derivatives in water catalyzed by hydroxyapatite

    EPA Science Inventory

    An expeditious and efficient protocol for the synthesis of naphthopyrans has been developed that proceeds via one-pot three-component sequential reaction in water catalyzed by hydroxyapatite or sodium-modified-hydroxyapatite. The title compounds have been obtained in high yield a...

  5. One-pot four-component reaction for convenient synthesis of functionalized 1-benzamidospiro[indoline-3,4'-pyridines

    PubMed Central

    Wang, Chao; Jiang, Yan-Hong

    2014-01-01

    Summary The one-pot four-component reaction of benzohydrazide (2-picolinohydrazide), acetylenedicarboxylate, isatins and malononitrile (ethyl cyanoacetate) with triethylamine as base catalyst afforded functionalized 1-benzamidospiro[indoline-3,4'-pyridines] in good yields. 1H NMR spectra indicated that an equilibrium of cis/trans-conformations exist in the obtained products. PMID:25550730

  6. One-pot synthesis of monodispersed silica nanoparticles for diarylethene-based reversible fluorescence photoswitching in living cells.

    PubMed

    Jung, Hye-youn; You, Suyeon; Lee, Chaewoon; You, Seungkwon; Kim, Yoonkyung

    2013-09-01

    A small 29 nm monodispersed silica nanoparticle 1a was synthesized as a diarylethene-based reversible fluorescence photoswitch by copolymerizing silane precursors in one-pot including 3a and 4. Reversible photoswitching of nanoparticle 1a was successfully achieved in living cells to show its potential as a highly distinguishable and safe fluorescence probe for cell tracking. PMID:23863959

  7. One-pot bioethanol production from cellulose by co-culture of Acremonium cellulolyticus and Saccharomyces cerevisiae

    PubMed Central

    2012-01-01

    Background While the ethanol production from biomass by consolidated bioprocess (CBP) is considered to be the most ideal process, simultaneous saccharification and fermentation (SSF) is the most appropriate strategy in practice. In this study, one-pot bioethanol production, including cellulase production, saccharification of cellulose, and ethanol production, was investigated for the conversion of biomass to biofuel by co-culture of two different microorganisms such as a hyper cellulase producer, Acremonium cellulolyticus C-1 and an ethanol producer Saccharomyces cerevisiae. Furthermore, the operational conditions of the one-pot process were evaluated for maximizing ethanol concentration from cellulose in a single reactor. Results Ethanol production from cellulose was carried out in one-pot bioethanol production process. A. cellulolyticus C-1 and S. cerevisiae were co-cultured in a single reactor. Cellulase producing-medium supplemented with 2.5 g/l of yeast extract was used for productions of both cellulase and ethanol. Cellulase production was achieved by A. cellulolyticus C-1 using Solka-Floc (SF) as a cellulase-inducing substrate. Subsequently, ethanol was produced with addition of both 10%(v/v) of S. cerevisiae inoculum and SF at the culture time of 60 h. Dissolved oxygen levels were adjusted at higher than 20% during cellulase producing phase and at lower than 10% during ethanol producing phase. Cellulase activity remained 8–12 FPU/ml throughout the one-pot process. When 50–300 g SF/l was used in 500 ml Erlenmeyer flask scale, the ethanol concentration and yield based on initial SF were as 8.7–46.3 g/l and 0.15–0.18 (g ethanol/g SF), respectively. In 3-l fermentor with 50–300 g SF/l, the ethanol concentration and yield were 9.5–35.1 g/l with their yields of 0.12–0.19 (g/g) respectively, demonstrating that the one-pot bioethanol production is a reproducible process in a scale-up bioconversion of cellulose to ethanol. Conclusion A. cellulolyticus

  8. One-Pot Cascade Reactions Leading to Pyrido[2',1':2,3]imidazo[4,5-c][1,2,3]triazolo[1,5-a]quinolines under Bimetallic Relay Catalysis with Air as the Oxidant.

    PubMed

    Wang, Ze; Li, Bin; Zhang, Xinying; Fan, Xuesen

    2016-08-01

    In this paper, we report an efficient one-pot synthesis of 1,2,3-triazole/quinoline-fused imidazo[1,2-a]pyridines starting from 2-(2-bromophenyl)imidazo[1,2-a]pyridines, alkynes, and sodium azide. This novel method involves a one-pot bimetallic relay-catalyzed cascade process combining azide-alkyne cycloaddition, C-N coupling between 1,2,3-triazole and aryl bromide, and intramolecular cross dehydrogenative C-C coupling between 1,2,3-triazole and imidazo[1,2-a]pyridine. Notable features of this protocol include simple starting materials, sustainable oxidants, reduced synthetic steps, and high efficiency. PMID:27351209

  9. One-pot phase transfer and surface modification of CdSe-ZnS quantum dots using a synthetic functional copolymer.

    PubMed

    Finetti, Chiara; Colombo, Miriam; Prosperi, Davide; Alessio, Giulia; Morasso, Carlo; Sola, Laura; Chiari, Marcella

    2014-01-01

    We present a facile, one-pot procedure for the organic-to-water phase transfer and biofunctionalization of semiconductor nanocrystals (quantum dots, or QDs) which employs a synthetic functional copolymer, namely poly(DMA-NAS-MAPS), consisting of three components: a surface interacting monomer, N,N-dimethylacrylamide (DMA), a chemically reactive monomer, N-acryloyloxysuccinimide (NAS), and a silane monomer, [3-(methacryloyloxy)-propyl]-trimethoxysilane (MAPS). The nanocrystals were transferred to water by exploiting the amphiphilic character of the copolymer backbone. Hydrolyzed MAPS units contributed to improve the solubility of QDs in water, whereas NAS exhibited reactivity toward biomolecules. A solution of streptavidin in phosphate buffer exhibited good dispersion ability leading to a clear and transparent colloidal suspension, indicative of good QD dispersion during phase transfer and purification. Unlike most of the published methods, the proposed functionalization approach does not require coupling agents and multistep reactions. PMID:24225905

  10. Coupling Multi-Component Models with MPH on Distributed MemoryComputer Architectures

    SciTech Connect

    He, Yun; Ding, Chris

    2005-03-24

    A growing trend in developing large and complex applications on today's Teraflop scale computers is to integrate stand-alone and/or semi-independent program components into a comprehensive simulation package. One example is the Community Climate System Model which consists of atmosphere, ocean, land-surface and sea-ice components. Each component is semi-independent and has been developed at a different institution. We study how this multi-component, multi-executable application can run effectively on distributed memory architectures. For the first time, we clearly identify five effective execution modes and develop the MPH library to support application development utilizing these modes. MPH performs component-name registration, resource allocation and initial component handshaking in a flexible way.

  11. One-pot synthesis of enantiomerically pure N-protected allylic amines from N-protected α-amino esters

    PubMed Central

    Silveira-Dorta, Gastón; Álvarez-Méndez, Sergio J; Martín, Víctor S

    2016-01-01

    Summary An improved protocol for the synthesis of enantiomerically pure allylic amines is reported. N-Protected α-amino esters derived from natural amino acids were submitted to a one-pot tandem reduction–olefination process. The sequential reduction with DIBAL-H at −78 °C and subsequent in situ addition of organophosphorus reagents yielded the corresponding allylic amines without the need to isolate the intermediate aldehyde. This circumvents the problem of instability of the aldehydes. The method tolerates well both Wittig and Horner–Wadsworth–Emmons organophosphorus reagents. A better Z-(dia)stereoselectivity was observed when compared to the previous one-pot method. The (dia)stereoselectivity of the process was affected neither by the reaction solvent nor by the amount of DIBAL-H employed. The method is compatible with the presence of free hydroxy groups as shown with serine and threonine derivatives. PMID:27340486

  12. One-pot synthesis of enantiomerically pure N-protected allylic amines from N-protected α-amino esters.

    PubMed

    Silveira-Dorta, Gastón; Álvarez-Méndez, Sergio J; Martín, Víctor S; Padrón, José M

    2016-01-01

    An improved protocol for the synthesis of enantiomerically pure allylic amines is reported. N-Protected α-amino esters derived from natural amino acids were submitted to a one-pot tandem reduction-olefination process. The sequential reduction with DIBAL-H at -78 °C and subsequent in situ addition of organophosphorus reagents yielded the corresponding allylic amines without the need to isolate the intermediate aldehyde. This circumvents the problem of instability of the aldehydes. The method tolerates well both Wittig and Horner-Wadsworth-Emmons organophosphorus reagents. A better Z-(dia)stereoselectivity was observed when compared to the previous one-pot method. The (dia)stereoselectivity of the process was affected neither by the reaction solvent nor by the amount of DIBAL-H employed. The method is compatible with the presence of free hydroxy groups as shown with serine and threonine derivatives. PMID:27340486

  13. Divergent synthesis of chiral heterocycles via sequencing of enantioselective three-component reactions and one-pot subsequent cyclization reactions.

    PubMed

    Tang, Min; Xing, Dong; Huang, Haoxi; Hu, Wenhao

    2015-07-01

    A highly efficient sequencing of catalytic asymmetric three-component reactions of alcohols, diazo compounds and aldimines/aldehydes with one-pot subsequent cyclization reactions was reported. The development of a robust and versatile Rh(ii)/Zr(iv)-BINOL co-catalytic system not only gives high diastereo- and enantioselective controls of the three-component reaction, but also shows excellent functionality tolerances that allow a wide range of functionalities to be pre-installed in each component and readily undergo one-pot subsequent cyclization reactions, thus providing rapid and diversity-oriented synthesis (DOS) of different types of chiral nitrogen- and/or oxygen-containing polyfunctional heterocycles. PMID:25864421

  14. Gold Nanoparticles Supported on a Layered Double Hydroxide as Efficient Catalysts for the One-Pot Synthesis of Flavones.

    PubMed

    Yatabe, Takafumi; Jin, Xiongjie; Yamaguchi, Kazuya; Mizuno, Noritaka

    2015-11-01

    Flavones are a class of natural products with diverse biological activities and have frequently been synthesized by step-by-step procedures using stoichiometric amounts of reagents. Herein, a catalytic one-pot procedure for the synthesis of flavone and its derivatives is developed. In the presence of gold nanoparticles supported on a Mg-Al layered double hydroxide (Au/LDH), various kinds of flavones can be synthesized starting from 2'-hydroxyacetophenones and benzaldehydes (or benzyl alcohols). The present one-pot procedure consists of a sequence of several reactions, and Au/LDH can catalyze all these different types of reactions. The catalysis is shown to be truly heterogeneous, and Au/LDH can be readily recovered and reused. PMID:26367015

  15. Novel and efficient one-pot tandem synthesis of 2-styryl-substituted 4(3H)-quinazolinones.

    PubMed

    Dabiri, Minoo; Baghbanzadeh, Mostafa; Delbari, Akram Sadat

    2008-01-01

    A novel one-pot tandem synthesis of 2-styryl-4(3 H)-quinazolinones in an acidic ionic liquid is reported. In this procedure isatoic anhydride, a primary aniline or ammonium acetate, and triethylorthoacetate are reacted in the presence of imidazolium trifluoroacetate [Hmim]TFA. Subsequently an aromatic aldehyde is added to the mixture to afford the title compounds in high to excellent yields. PMID:18671434

  16. One-pot microwave-assisted protocol for the synthesis of substituted 2-amino-1H-imidazoles.

    PubMed

    Ermolat'ev, D S; Savaliya, B; Shah, A; Van der Eycken, E

    2011-05-01

    An efficient microwave-assisted one-pot two-step protocol was developed for the construction of disubstituted 2-amino-1H-imidazoles. This process involves the sequential formation of 2,3-dihydro-2-hydroxyimidazo[1,2-a]pyrimidinium salts from readily available 2-aminopyrimidines and α-bromoketones, followed by cleavage of the pyrimidine ring with hydrazine. PMID:20740313

  17. A quadruple cascade protocol for the one-pot synthesis of fully-substituted hexahydroisoindolinones from simple substrates.

    PubMed

    Zhang, Hong-Bo; Luo, Yong-Chun; Hu, Xiu-Qin; Liang, Yong-Min; Xu, Peng-Fei

    2016-01-01

    A new and efficient synthetic method to obtain fully-substituted hexahydroisoindolinones was developed by using bifunctional tertiary amine-thioureas as powerful catalysts. As far as we know, there is no efficient synthetic method developed toward fully-substituted hexahydroisoindolinones. The products were obtained in good yield and diastereoselectivity. The one-pot cascade quadruple protocol features readily available starting materials, simple manipulation, mild conditions and good atom economy. PMID:26977184

  18. Flowerlike WSe2 and WS2 microspheres: one-pot synthesis, formation mechanism and application in heavy metal ion sequestration.

    PubMed

    Li, Wei; Chen, Dehong; Xia, Fang; Tan, Jeannie Z Y; Song, Jingchao; Song, Wei-Guo; Caruso, Rachel A

    2016-03-15

    Flowerlike WSe2 and WS2 microspheres were synthesized by a facile and scalable one-pot solvothermal method. Their formation mechanism followed the reaction between dissolved W(CO)6 and dissolved S or melted Se without complete decomposition of W(CO)6 into tungsten. As novel efficient sorbents, WSe2 and WS2 demonstrated outstanding uptake capacities for Pb(2+) and Hg(2+). PMID:26932785

  19. "One-Pot" Approach to 8-Acylated 2-Quinolinones via Palladium-Catalyzed Regioselective Acylation of Quinoline N-Oxides.

    PubMed

    Chen, Xiaopei; Cui, Xiuling; Wu, Yangjie

    2016-05-20

    A "one-pot" facile and efficient protocol for 8-acylated 2-quinolinones has been developed through palladium-catalyzed acylation of quinoline N-oxides, which proceeds with high selectivity at the C8-position. The desired products were isolated in up to 95% yield and good functional group tolerance. A palladacycle was isolated from the catalytic process and proposed as a key intermediate. PMID:27153298

  20. Odorless, One-Pot Regio- and Stereoselective Iodothiolation of Alkynes with Sodium Arenesulfinates under Metal-Free Conditions in Water.

    PubMed

    Lin, Ya-mei; Lu, Guo-ping; Cai, Chun; Yi, Wen-bin

    2015-07-01

    A newly developed regio- and stereoselective radical addition of alkyne under metal-free conidtions has been disclosed. This chemistry, in which odorless sodium arenesulfinates in place of thiols are used as the sulfur reagent, provides an efficient, one-pot approach for the generation of β-iodoalkenyl sulfides, which can be easily further functionalized to derive various alkenes and alkynyl sulfides rendering this methodology attractive to both synthetic and medicinal chemistry. PMID:26084011

  1. A quadruple cascade protocol for the one-pot synthesis of fully-substituted hexahydroisoindolinones from simple substrates

    PubMed Central

    Zhang, Hong-Bo; Luo, Yong-Chun; Hu, Xiu-Qin; Liang, Yong-Min

    2016-01-01

    Summary A new and efficient synthetic method to obtain fully-substituted hexahydroisoindolinones was developed by using bifunctional tertiary amine-thioureas as powerful catalysts. As far as we know, there is no efficient synthetic method developed toward fully-substituted hexahydroisoindolinones. The products were obtained in good yield and diastereoselectivity. The one-pot cascade quadruple protocol features readily available starting materials, simple manipulation, mild conditions and good atom economy. PMID:26977184

  2. One-pot synthesis of indenonaphthopyrans catalyzed by copper(II) triflate: a comparative study of reflux and ultrasound methods.

    PubMed

    Turhan, Kadir; Ozturkcan, S Arda; Uluer, Mehmet; Turgut, Zuhal

    2014-01-01

    An effective and environment-friendly protocol for the synthesis of indenonaphthopyrans has been developed by one-pot reaction of 2-naphthol, various aromatic aldehydes and 1,3-indandione, in the presence of copper(II) triflate as the catalyst while using reflux (Method A) and ultrasound (Method B). The Method B approach offers the advantages of a simple reaction method, short reaction time, excellent yield, and showcases the economic importance of the catalysts for such processes. PMID:25286219

  3. Amino- and Sulfo-Bifunctionalized Metal-Organic Frameworks: One-Pot Tandem Catalysis and the Catalytic Sites.

    PubMed

    Liu, Hui; Xi, Fu-Gui; Sun, Wei; Yang, Ning-Ning; Gao, En-Qing

    2016-06-20

    New MIL-101 metal-organic frameworks (MOFs) dually functionalized with amino and sulfo groups were fabricated by postsynthetic modification and used to catalyze one-pot deacetalization-Knoevenagel condensation. We proved that the MOFs take the zwitterionic form, with the catalytic acid site being the ammonium group rather than the sulfo one. The acid and base concentrations in the materials are correlated, and the ratio can be readily tuned to achieve optimal catalytic performance. PMID:27254287

  4. Efficient microwave-assisted one-pot preparation of angular 2,2-dimethyl-2H-chromone containing compounds

    PubMed Central

    Zhou, Ting; Shi, Qian; Lee, Kuo Hsing

    2010-01-01

    A novel and efficient microwave-assisted one-pot reaction was developed to synthesize angular 2,2-dimethyl-2H-chromone containing compounds, which is the first and key step in the synthesis of potent DCK and DCP anti-HIV agents. The newly developed microwave synthesis conditions dramatically shortened the reaction time from 2 days to 4 hours with improved yields. PMID:20936082

  5. Palladium-Catalyzed Benzylic Arylation of Pyridylmethyl Silyl Ethers: One-Pot Synthesis of Aryl(pyridyl)methanols.

    PubMed

    Rivero, Alexandra R; Kim, Byeong-Seon; Walsh, Patrick J

    2016-04-01

    An efficient palladium-catalyzed direct arylation of pyridylmethyl silyl ethers with aryl bromides is described. A Pd(OAc)2/NIXANTPHOS-based catalyst provides aryl(pyridyl)methyl alcohol derivatives in good to excellent yields (33 examples, 57-100% yield). This protocol is compatible with different silyl ether protecting groups, affording either the protected or the free alcohols in an effective one-pot process. The scalability of the reaction is demonstrated. PMID:27004592

  6. One-pot hydrazide-based native chemical ligation for efficient chemical synthesis and structure determination of toxin Mambalgin-1.

    PubMed

    Pan, Man; He, Yao; Wen, Ming; Wu, Fangming; Sun, Demeng; Li, Sijian; Zhang, Longhua; Li, Yiming; Tian, Changlin

    2014-06-01

    An efficient one-pot chemical synthesis of snake venom toxin Mambalgin-1 was achieved using an azide-switch strategy combined with hydrazide-based native chemical ligation. Synthetic Mambalgin-1 exhibited a well-defined structure after sequential folding in vitro. NMR spectroscopy revealed a three-finger toxin family structure, and the synthetic toxin inhibited human acid-sensing ion channel 1a. PMID:24619065

  7. Combining silver catalysis and organocatalysis: a sequential Michael addition/hydroalkoxylation one-pot approach to annulated coumarins.

    PubMed

    Hack, Daniel; Chauhan, Pankaj; Deckers, Kristina; Hermann, Gary N; Mertens, Lucas; Raabe, Gerhard; Enders, Dieter

    2014-10-01

    A highly stereoselective one-pot procedure for the synthesis of five-membered annulated hydroxycoumarins has been developed. By merging primary amine catalysis with silver catalysis, a series of functionalized coumarin derivatives were obtained in good yields (up to 91%) and good to excellent enantioselectivities (up to 99% ee) via a Michael addition/hydroalkoxylation reaction. Depending on the substituents on the enynone, the synthesis of annulated six-membered rings is also feasible. PMID:25250728

  8. One-Pot Synthesis of Benzothiazole-Tethered Chromanones/Coumarins via Claisen Rearrangement Using the Solid State Melt Reaction.

    PubMed

    Bakthadoss, Manickam; Selvakumar, Raman

    2016-04-15

    A novel protocol has been successfully established for the efficient synthesis of benzothiazole-tethered chromanone/coumarin scaffolds via Claisen rearrangement using a solid state melt reaction in a one-pot manner. Benzothiazole formation and Claisen rearrangement involve the cleavage of S-S and C-O bonds and formation of C-S, C═N, and C-C bonds in a single operation without using a catalyst or solvent. PMID:26991666

  9. One-pot hydrothermal synthesis of zeolite/sodium tantalate composite and its photodegradation of methyl orange

    SciTech Connect

    Gu, Xiaoli; Lu, Haiqiang; Kan, Chun; Yao, Jianfeng

    2015-08-15

    Highlights: • Sodalite/NaTaO{sub 3} composite is prepared by a one-pot hydrothermal synthesis. • Enhanced photodegradation is achieved due to the heterogeneous doping effect. • Structure distortion is found for NaTaO{sub 3} after removing sodalite by acid washing. - Abstract: Sodalite/NaTaO{sub 3} composite was prepared by a one-pot hydrothermal synthesis method. Sodalite and NaTaO{sub 3} grow interpenetrated, and the resulting composites have similar morphology as the pure sodalite. The sodalite/NaTaO{sub 3} composite has a lower band gap of 3.35 eV due to the heterogeneous doping effect, and exhibits an enhanced photodegradation of methyl orange under UV irradiation as compared to the pure NaTaO{sub 3}. A slight structure distortion is found for NaTaO{sub 3} after removing sodalite by acid washing the sodalite/NaTaO{sub 3} composite, and such result further confirms the co-growth of the two crystals. This one-pot hydrothermal method opens up new avenues for the preparation of photocatalytic composites.

  10. One-pot synthesis of oxamidato-bridged hexarhenium trigonal prisms adorned with ester functionality.

    PubMed

    Nagarajaprakash, R; Govindarajan, R; Manimaran, Bala

    2015-07-14

    Oxamidato-bridged Re(I)-based hexanuclear trigonal prisms with ester functionality have been synthesised via a multicomponent self-assembly process under solvothermal conditions. The self-assembly of Re2(CO)10, oxamide ligands (H2L1 = N,N′-dibutyloxamide, H2L2 = N,N′-dioctyloxamide, H2L3 = N,N′-didodecyloxamide and H2L4 = N,N′-dibenzyloxamide) and phenyl-1,3,5-tris(isonicotinate) (ptin) resulted in the formation of metallaprisms with the general formula [{(CO)3Re(μ–η(4)-L)Re(CO)3}3(μ3-ptin)2] (1–4). The metallaprisms 1–4 have been characterised using spectroscopic techniques, and the molecular structure of 4 has been elucidated by single-crystal X-ray diffraction methods. Investigations on the guest binding ability of 2 with a few aromatic alcohols and L-tryptophan using UV–vis and fluorescence spectroscopic titration experiments revealed strong host–guest interactions. The luminescence enhancement studies of 2 and 3 have been carried out using organic-aqueous solvent mixtures. PMID:26050748

  11. Mesoporous Silica with Site-Isolated Amine and Phosphotungstic Acid Groups: A Solid Catalyst with Tunable Antagonistic Functions for One-Pot Tandem Reactions

    SciTech Connect

    Shiju N. R.; Syed K.; Alberts A.; Brown D. and Rothenberg G.

    2011-09-15

    A bifunctional solid catalyst is prepared by combining acid and base functions on mesoporous silica supports. The co-existence of these functions is shown by a two-step reaction sequence in one pot. Excellent product yields, which cannot be obtained by separated acid and base functions in one pot, show the validity of our concept.

  12. One-Pot Synthesis of (S)-Baclofen via Aldol Condensation of Acetaldehyde with Diphenylprolinol Silyl Ether Mediated Asymmetric Michael Reaction as a Key Step.

    PubMed

    Hayashi, Yujiro; Sakamoto, Daisuke; Okamura, Daichi

    2016-01-01

    An efficient asymmetric total synthesis of (S)-baclofen was accomplished via a one-pot operation from commercially available materials using sequential reactions, such as aldol condensation of acetaldehyde, diphenylprolinol silyl ether mediated asymmetric Michael reaction of nitromethane, Kraus-Pinnick oxidation, and Raney Ni reduction. Highly enantioenriched baclofen was obtained in one pot with a good yield over four reactions. PMID:26636719

  13. Coupling between geochemical reactions and multicomponent gas and solute transport in unsaturated media: A reactive transport modeling study

    NASA Astrophysics Data System (ADS)

    Molins, S.; Mayer, K. U.

    2007-05-01

    The two-way coupling that exists between biogeochemical reactions and vadose zone transport processes, in particular gas phase transport, determines the composition of soil gas. To explore these feedback processes quantitatively, multicomponent gas diffusion and advection are implemented into an existing reactive transport model that includes a full suite of geochemical reactions. Multicomponent gas diffusion is described on the basis of the dusty gas model, which accounts for all relevant gas diffusion mechanisms. The simulation of gas attenuation in partially saturated landfill soil covers, methane production, and oxidation in aquifers contaminated by organic compounds (e.g., an oil spill site) and pyrite oxidation in mine tailings demonstrate that both diffusive and advective gas transport can be affected by geochemical reactions. Methane oxidation in landfill covers reduces the existing upward pressure gradient, thereby decreasing the contribution of advective methane emissions to the atmosphere and enhancing the net flux of atmospheric oxygen into the soil column. At an oil spill site, methane oxidation causes a reversal in the direction of gas advection, which results in advective transport toward the zone of oxidation both from the ground surface and the deeper zone of methane production. Both diffusion and advection contribute to supply atmospheric oxygen into the subsurface, and methane emissions to the atmosphere are averted. During pyrite oxidation in mine tailings, pressure reduction in the reaction zone drives advective gas flow into the sediment column, enhancing the oxidation process. In carbonate-rich mine tailings, calcite dissolution releases carbon dioxide, which partly offsets the pressure reduction caused by O2 consumption.

  14. Ceria-Vanadia/Silica-Catalyzed Cascade for C-C and C-O Bond Activation: Green One-Pot Synthesis of 2-Amino-3-cyano-4H-pyrans.

    PubMed

    Maddila, Surya Narayana; Maddila, Suresh; van Zyl, Werner E; Jonnalagadda, Sreekantha B

    2016-02-01

    We designed a ceria-vanadia/silica (Ce-V/SiO2) heterogeneous catalyst and used it for the green and efficient synthesis of 2-amino-3-cyano-4H-pyran derivatives. The green reaction was a multicomponent one-pot condensation of 5,5-dimethylcyclohexane-1,3-dione, aromatic aldehyde, and malononitrile in an eco-compatible solvent (ethanol). The catalyst was synthesized and fully characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. The reported procedure offers a number of advantages including decreased reaction times, mild conditions, high yields, operational simplicity, and environmentally benign and simple work-up procedures. Furthermore, the catalyst is economical, fully recyclable, and reusable for over five runs while preserving its high activity. The synthesized 2-amino-3-cyano-4H-pyran products can later be used for pharmaceutical purposes. PMID:27308209

  15. HYDROGEOCHEM: A coupled model of HYDROlogic transport and GEOCHEMical equilibria in reactive multicomponent systems

    SciTech Connect

    Yeh, G.T.; Tripathi, V.S.

    1990-11-01

    This report presents the development of a hydrogeochemical transport model for multicomponent systems. The model is designed for applications to proper hydrological setting, accommodation of complete suite of geochemical equilibrium processes, easy extension to deal with chemical kinetics, and least constraints of computer resources. The hydrological environment to which the model can be applied is the heterogeneous, anisotropic, saturated-unsaturated subsurface media under either transient or steady state flow conditions. The geochemical equilibrium processes included in the model are aqueous complexation, adsorption-desorption, ion exchange, precipitation-dissolution, redox, and acid-base reactions. To achieve the inclusion of the full complement of these geochemical processes, total analytical concentrations of all chemical components are chosen as the primary dependent variables in the hydrological transport equations. Attendant benefits of this choice are to make the extension of the model to deal with kinetics of adsorption-desorption, ion exchange, precipitation-dissolution, and redox relatively easy. To make the negative concentrations during the iteration between the hydrological transport and geochemical equilibrium least likely, an implicit form of transport equations are proposed. To alleviate severe constraints of computer resources in terms of central processing unit (CPU) time and CPU memory, various optional numerical schemes are incorporated in the model. The model consists of a hydrological transport module and geochemical equilibrium module. Both modules were thoroughly tested in code consistency and were found to yield plausible results. The model is verified with ten examples. 79 refs., 21 figs., 17 tabs.

  16. Tidal Calibration of Multicomponent Borehole Strainmeters: The Roles of Vertical and Shear Coupling

    NASA Astrophysics Data System (ADS)

    Roeloffs, E.

    2008-12-01

    To measure tectonic strain, a borehole strainmeter is designed to deform more than the surrounding formation, but the precise coupling parameters relating strainmeter output to formation strain depend on local rock moduli and therefore must be estimated after installation. Usually this "calibration" procedure entails estimating the amplitudes and phases of the M2 and O1 earth tide variations in the strainmeter output, and choosing coupling parameters to reconcile them with model-calculated tides. For many of the Plate Boundary Observatory Gladwin Tensor Strainmeters (PBO GTSMs), two modifications to previously published coupling models can greatly improve agreement with model tides. The PBO GTSMs each consist of four horizontal extensometers. The first important modification is that each extensometer is coupled to vertical strain, a feature motivated by the PBO GTSMs' large responses to atmospheric pressure changes. Some PBO GTSMs respond strongly enough to vertical coupling that the free-surface extension induced by areal contraction results in a negative apparent areal-strain coupling parameter. Rotating the tidal strains to x,y coordinates with the x-axis parallel to each extensometer illuminates the second modification. The extensometer is expected to be positively coupled to ɛxx, negatively and less strongly coupled to ɛyy, and uncoupled to ɛxy. However, allowing some extensometers of some PBO GTSMs to have a small coupling to ɛxy can bring the model and observed tides into good agreement, and is not unreasonable given that the strainmeter host rock is not perfectly uniform or isotropic. Graphical inspection of the extensometer and model tide phasors reveals which extensometers appear coupled to ɛxy, although for at least two GTSMs, this shows that only negative coupling to ɛxx-ɛyy could reconcile the observed and model tides. Unfortunately, if all 4 extensometers require ɛxy coupling, there is a trade-off between the coupling parameters and an

  17. One-pot three-component Mannich-type reactions using sulfamic acid catalyst under ultrasound irradiation.

    PubMed

    Zeng, Hongyao; Li, Hua; Shao, Huawu

    2009-08-01

    Sulfamic acid (NH(2)SO(3)H, SA) was used as an efficient, inexpensive, non-toxic and recyclable green catalyst for the ultrasound-assisted one-pot Mannich reaction of aldehydes with ketones and amines. This ultrasound protocol has advantages of high yield, mild condition, no environmental pollution, and simple work-up procedures. Most importantly, beta-aminocarbonyl compounds with ortho-substituted aromatic amines are obtained in acceptable to good yields by this methodology for the first time. PMID:19394889

  18. One-pot self-assembly of Cu2O/RGO composite aerogel for aqueous photocatalysis

    NASA Astrophysics Data System (ADS)

    Cai, Jingyu; Liu, Wenjun; Li, Zhaohui

    2015-12-01

    Cu2O/reduced graphene oxide (RGO) composite aerogel was fabricated by a one-pot hydrothermal method using glucose as a reducing agent and cross-linker. The as-obtained Cu2O/RGO composite aerogel showed superior photocatalytic activity for MO degradation owing to its improved light absorption capability, enhanced adsorption toward pollutant and the RGO promoted charge carrier separation. The Cu2O/RGO composite aerogel can also be facilely separated from the reaction system for recycling, which makes it especially appealing for using as a visible light responsive photocatalyst in aqueous photocatalysis.

  19. One-pot odourless synthesis of thioesters via in situ generation of thiobenzoic acids using benzoic anhydrides and thiourea.

    PubMed

    Abbasi, Mohammad; Khalifeh, Reza

    2015-01-01

    An efficient and odourless procedure for a one-pot synthesis of thioesters by the reaction of benzoic anhydrides, thiourea and various organic halides (primary, allylic, and benzylic) or structurally diverse, electron-deficient alkenes (ketones, esters, and nitriles) in the presence of Et3N has been developed. In this method, thiobenzoic acids were in situ generated from the reaction of thiourea with benzoic anhydrides, which were subjected to conjugate addition with electron-deficient alkenes or a nucleophilic displacement reaction with alkyl halides. PMID:26425185

  20. One-Pot Sulfoxide Synthesis Exploiting a Sulfinyl-Dication Equivalent Generated from a DABSO/Trimethylsilyl Chloride Sequence.

    PubMed

    Lenstra, Danny C; Vedovato, Vincent; Ferrer Flegeau, Emmanuel; Maydom, Jonathan; Willis, Michael C

    2016-05-01

    A one-pot process for the synthesis of unsymmetrical sulfoxides using organometallic nucleophiles is described. Sulfur dioxide, delivered from the surrogate DABSO (DABCO-bis(sulfur dioxide)), acts as the initial electrophile and combines with the first organometallic reagent to generate a sulfinate intermediate. In situ conversion of the sulfinate to a sulfinate silyl ester, using TMS-Cl (trimethylsilyl chloride), generates a second electrophile, allowing addition of a second organometallic reagent. Organolithium or Grignard reagents can be employed, delivering sulfoxides in good to excellent yields. PMID:27082825

  1. One-pot synthesis and cytotoxicity studies of new Mannich base derivatives of polyether antibiotic--lasalocid acid.

    PubMed

    Huczyński, Adam; Rutkowski, Jacek; Borowicz, Izabela; Wietrzyk, Joanna; Maj, Ewa; Brzezinski, Bogumil

    2013-09-15

    Seven Mannich base derivatives of polyether antibiotic Lasalocid acid (2a-2g) were synthesized and screened for their antiproliferative activity against various human cancer cell lines. A novel chemoselective one-pot synthesis of these Mannich bases was developed. Compounds 2a-2c and 2g with sterically smaller dialkylamine substituent, displayed potent antiproliferative activity (IC50: 3.2-7.3 μM), and demonstrated higher than twofold selectivity for specific type of cancer. The nature of Mannich base substituent on C-2 atom at the aromatic ring may be critical in the search for selectivity towards a particular cancer cell. PMID:23932361

  2. Investigation of α-Thioglycoside Donors: Reactivity Studies toward Configuration-Controlled Orthogonal Activation in One-Pot Systems.

    PubMed

    Smith, Raymond; Müller-Bunz, Helge; Zhu, Xiangming

    2016-08-01

    The influence of anomeric configuration upon thioglycoside donors remains relatively unexplored. Utilizing methodology developed for the stereoselective and high-yielding synthesis of α-glycosyl thiols, a series of α-thioglycosides were synthesized, and their reactivity was compared to that of their β-counterparts. The highly selective activation observed for anomeric pairs containing a 2-O-acyl moiety and additional findings are reported. Application of a pair of "superarmed" thioglycosides to a one-pot oligosaccharide system is also described, in which selectivity is a result of configuration-based orthogonal activation. PMID:27399930

  3. Facile rhenium-peptide conjugate synthesis using a one-pot derived Re(CO)3 reagent.

    PubMed

    Chanawanno, Kullapa; Kondeti, Vinay; Caporoso, Joel; Paruchuri, Sailaja; Leeper, Thomas C; Herrick, Richard S; Ziegler, Christopher J

    2016-03-21

    We have synthesized two Re(CO)3-modified lysine complexes (1 and 2), where the metal is attached to the amino acid at the Nε position, via a one-pot Schiff base formation reaction. These compounds can be used in the solid phase synthesis of peptides, and to date we have produced four conjugate systems incorporating neurotensin, bombesin, leutenizing hormone releasing hormone, and a nuclear localization sequence. We observed uptake into human umbilical vascular endothelial cells as well as differential uptake depending on peptide sequence identity, as characterized by fluorescence and rhenium elemental analysis. PMID:26863280

  4. One-pot synthesis and antifungal activity against plant pathogens of quinazolinone derivatives containing an amide moiety.

    PubMed

    Zhang, Jin; Liu, Jia; Ma, Yangmin; Ren, Decheng; Cheng, Pei; Zhao, Jiawen; Zhang, Fan; Yao, Yuan

    2016-05-01

    An efficient one-pot, three-component synthesis of quinazolinone derivatives containing 3-acrylamino motif was carried out using CeO2 nanoparticles as catalyst. Thirty-nine synthesized compounds were obtained with satisfied yield and elucidated by spectroscopic analysis. Four phytopathogenic fungi were chosen to test the antifungal activities by minimum inhibitory concentration (MIC) method. Compounds 4ag, 4bb, 4bc showed broad antifungal activities against at least three fungi, and dramatic effects of substituents on the activities were observed. Docking studies were established to explore the potential antifungal mechanism of quinazolinone derivatives as the chitinase inhibitors, and also verified the importance of the amide moiety. PMID:27040656

  5. A convenient four-component one-pot strategy toward the synthesis of pyrazolo[3,4-d]pyrimidines

    PubMed Central

    Liu, Mingxing; Li, Jiarong; Chai, Hongxin; Zhang, Kai; Yang, Deli; Zhang, Qi

    2015-01-01

    Summary An efficient one-pot synthesis of pyrazolo[3,4-d]pyrimidine derivatives by the four-component condensation of hydrazines, methylenemalononitriles, aldehydes and alcohols has been developed via two different reaction pathways. The structures of target products were characterized by IR spectroscopy, NMR (1H and 13C) spectroscopy and HRMS (ESI) spectrometry. The crystal structure of 4-ethoxy-6-(2-nitrophenyl)-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine was determined by single crystal X-ray diffraction. PMID:26664633

  6. One-pot regio- and stereoselective synthesis of α'-methoxy-γ-pyrones: biological evaluation as mitochondrial respiratory complex inhibitors.

    PubMed

    Rosso, Helena; De Paolis, Michaël; Collin, Valérie C; Dey, Sriloy; Hecht, Sidney M; Prandi, Cristina; Richard, Vincent; Maddaluno, Jacques

    2011-11-18

    The one-pot construction of functionalized α'-methoxy-γ-pyrones is detailed. Starting from α,α'-dimethoxy-γ-pyrone, molecular diversity is attained by a regio- and stereoselective desymmetrization using allyllithium followed by vinylogous aldol reaction. Mechanistic considerations including density functional theory calculations and insightful experiments have been gathered to shed light on this complex multistep process. To illustrate the versatility of this methodology, some of the molecules prepared were evaluated for their ability to inhibit NADH-oxidase and NADH-ubiquinone oxidoreductase. In the process, a potent new inihibitor of NADH-oxidase activity (IC(50) 44 nM) was identified. PMID:22011074

  7. Brönsted Acid-Catalyzed One-Pot Synthesis of Indoles from o-Aminobenzyl Alcohols and Furans

    PubMed Central

    Kuznetsov, Alexey; Makarov, Anton; Rubtsov, Alexandr E.; Butin, Alexander V.; Gevorgyan, Vladimir

    2013-01-01

    Brönsted acid-catalyzed one-pot synthesis of indoles from o-aminobenzyl alcohols and furans has been developed. This method operates via the in situ formation of aminobenzylfuran, followed by its recyclization into the indole core. The method proved to be efficient for substrates possessing different functional groups, including -OMe, -CO2Cy, and -Br. The resulting indoles can easily be transformed into diverse scaffolds, including 2,3- and 1,2-fused indoles, and indole possessing an α,β-unsaturated ketone moiety at the C-2 position. PMID:24255969

  8. One-pot transformation of cellobiose to formic acid and levulinic acid over ionic-liquid-based polyoxometalate hybrids.

    PubMed

    Li, Kaixin; Bai, Linlu; Amaniampong, Prince Nana; Jia, Xinli; Lee, Jong-Min; Yang, Yanhui

    2014-09-01

    Currently, levulinic acid (LA) and formic acid (FA) are considered as important carbohydrates for the production of value-added chemicals. Their direct production from biomass will open up a new opportunity for the transformation of biomass resource to valuable chemicals. In this study, one-pot transformation of cellobiose into LA and FA was demonstrated, using a series of multiple-functional ionic liquid-based polyoxometalate (IL-POM) hybrids as catalytic materials. These IL-POMs not only markedly promoted the production of valuable chemicals including LA, FA and monosaccharides with high selectivities, but also provided great convenience of the recovery and the reuse of the catalytic materials in an environmentally friendly manner. Cellobiose conversion of 100%, LA selectivity of 46.3%, and FA selectivity of 26.1% were obtained at 423 K and 3 MPa for 3 h in presence of oxygen. A detailed catalytic mechanism for the one-pot transformation of cellobiose was also presented. PMID:25110998

  9. One pot synthesis of Ag nanoparticle modified ZnO microspheres in ethylene glycol medium and their enhanced photocatalytic performance

    SciTech Connect

    Tian Chungui; Li Wei; Pan Kai; Zhang Qi; Tian Guohui; Zhou Wei; Fu Honggang

    2010-11-15

    Ag nanoparticles (NPs) modified ZnO microspheres (Ag/ZnO microspheres) were prepared by a facile one pot strategy in ethylene glycol (EG) medium. The EG played two important roles in the synthesis: it could act as a reaction media for the formation of ZnO and reduce Ag{sup +} to Ag{sup 0}. A series of the characterizations indicated the successful combination of Ag NPs with ZnO microspheres. It was shown that Ag modification could greatly enhance the photocatalytic efficiency of ZnO microspheres by taking the photodegradation of Rhodamine B as a model reaction. With appropriate ratio of Ag and ZnO, Ag/ZnO microspheres showed the better photocatalytic performance than commercial Degussa P-25 TiO{sub 2}. Photoluminescence and surface photovoltage spectra demonstrated that Ag modification could effectively inhibit the recombination of the photoinduced electron and holes of ZnO. This is responsible for the higher photocatalytic activity of Ag/ZnO composites. -- Graphical abstract: A 'one-pot' strategy was developed for preparing the Ag/ZnO microspheres in ethylene glycol. The composites exhibited superior photocatalytic performance for photodegradation of Rhodamine B dye in water. Display Omitted

  10. Whole-cell based solvent-free system for one-pot production of biodiesel from waste grease.

    PubMed

    Li, Aitao; Ngo, Thao P N; Yan, Jinyong; Tian, Kaiyuan; Li, Zhi

    2012-06-01

    A whole-cell based solvent-free system was developed for efficient conversion of waste grease to biodiesel via one-pot esterification and transesterification. By isolation and screening of lipase-producing strains from soil, Serratia marcescens YXJ-1002 was discovered for the biotransformation of grease to biodiesel. The lipase (SML) from this strain was cloned and expressed in Escherichia coli as an intracellular enzyme, showing 6 times higher whole-cell based hydrolysis activity than that of wild type strain. The recombinant cells were used for biodiesel production from waste grease in one-pot reactions containing no solvent with the addition of methanol in several small portions, and 97% yield of biodiesel (FAME) was achieved under optimized conditions. In addition, the whole-cell biocatalysts showed excellent reusability, retaining 74% productivity after 4 cycles. The developed system, biocatalyst, and process enable the efficient, low-cost, and green production of biodiesel from waste grease, providing with a potential industrial application. PMID:22483351

  11. One-pot β-cyclodextrin-assisted extraction of active ingredients from Xue-Zhi-Ning basing its encapsulated ability.

    PubMed

    Zhang, Hui-Jie; Liu, Ya-Nan; Wang, Meng; Wang, Yue-Fei; Deng, Yan-Ru; Cui, Ming-Lei; Ren, Xiao-Liang; Qi, Ai-Di

    2015-11-01

    Xue-Zhi-Ning (XZN) is a traditional Chinese medicine formula, containing active ingredients with poor solubility in water, which has been demonstrated to be helpful for patients with hyperlipidemia. One-pot β-cyclodextrin (β-CD)-assisted extraction of active ingredients from XZN has been carried out to develop an efficient and eco-friendly extraction process. Five active compounds--rubrofusarin gentiobioside, 2,3,5,4'-tetrahydroxy-stilbene-2-O-β-D-glucoside, emodin, nuciferine and quercetin--were identified by UPLC/DAD/MS and used as indexes to evaluate the process optimized by an orthogonal test. The results showed that addition of β-CD significantly enhanced the extraction ratios of all five components. The enhancement of extraction ratios was positively correlated with the apparent formation constants between β-CD and the compounds. The study also showed that the stabilities and dissolution rates of the active ingredients were improved in the presence of β-CD. This one-pot β-cyclodextrin-assisted extraction has the potential to be applied in pharmaceutical preparations directly. PMID:26256368

  12. Highly Photoluminescent Molybdenum Oxide Quantum Dots: One-Pot Synthesis and Application in 2,4,6-Trinitrotoluene Determination.

    PubMed

    Xiao, Sai Jin; Zhao, Xiao Jing; Hu, Ping Ping; Chu, Zhao Jun; Huang, Cheng Zhi; Zhang, Li

    2016-03-30

    As a well-studied transition-metal semiconductor material, MoOx has a wider band gap than molybdenum disulfide (MoS2), and its property varies dramatically for the existence of several different allotropes and suboxide phases of molybdenum oxides (MoOx, x < 3). In this manuscript, a one-pot method possessing the advantages of one pot, easily prepared, rapid, and environmentally friendly, has been developed for facile synthesis of highly photoluminescent MoOx quantum dots (MoOx QDs), in which commercial molybdenum disulfide (MoS2) powder and hydrogen peroxide (H2O2) are employed as the precursor and oxidant, respectively. The obtained MoOx QDs can be further utilized as an efficient photoluminescent probe, and a new turn-off sensor is developed for 2,4,6-trinitrotoluene (TNT) determination based on the fact that the photoluminescence of MoOx QDs can be quenched by the Meisenheimer complexes formed in the strong alkali solution through the inner filter effect (IFE). Under the optimal conditions, the decreased photoluminescence of MoOx QDs shows a good linear relationship to the concentration of TNT ranging from 0.5 to 240.0 μM, and the limit of detection was 0.12 μM (3σ/k). With the present turn-off sensor, TNT in river water samples can be rapidly and selectively detected without tedious sample pretreatment processes. PMID:26954663

  13. One-pot construction of boronate ester based pH-responsive micelle for combined cancer therapy.

    PubMed

    Chen, Jing-Xiao; Shi, Yu; Zhang, Yi-Rang; Teng, Li-Ping; Chen, Jing-Hua

    2016-07-01

    In this study, one-pot strategy for the construction of micelles loaded with two types of anticancer drugs (i.e., doxorubicin and methotrexate) together is reported. On the basis of the reaction between boronic acid and 1,2-diol to form boronate ester, the formation of amphiphiles, their self-assembly into micelles and drug encapsulation occurs simultaneously under simple dialysis at the appropriate pH condition. In the one-pot strategy, the micelle yield is high (78.2%) and the drug encapsulation efficiency of the two drugs is improved compared with that of the traditional method. The micelles can selectively increase the drug release ratio at acidic pH, showing the pH-responsive behavior inherited from the property of boronate ester. By combining doxorubicin and methotrexate, the half-maximum inhibition concentrations of the two drugs are obviously reduced, showing synergistic efficacy against cancer cells. This strategy is promising and may be expanded to various applications. PMID:27022868

  14. One-pot synthesis of co-substituted manganese oxide nanosheets and physical properties of lamellar aggregates

    SciTech Connect

    Kai, Kazuya; Cuisinier, Marine; Yoshida, Yukihiro; Saito, Gunzi; Kobayashi, Yoji; Kageyama, Hiroshi

    2012-11-15

    Graphical abstract: Display Omitted Highlights: ► Solid solution nanosheets, (Mn{sub 1−x}Co{sub x})O{sub 2}, synthesized via facile one-pot process. ► The structural characterization of nanosheets revealing a single (Mn,Co)O{sub 2} layer and the solubility limit as x ∼ 0.20. ► The invariant charge density of the layer upon Co substitution. ► Systematic dependence of magnetic and optical properties of the lamellar aggregates. -- Abstract: Co-substituted manganese oxide nanosheets, (Mn{sub 1−x}Co{sub x})O{sub 2} have been synthesized in the form of a colloidal suspension via a simple one-pot method. Substitution effects on the structural, optical absorption, and magnetic properties are investigated for the nanosheets and their lamellar aggregates. The composition of the (Mn{sub 1−x}Co{sub x})O{sub 2} nanosheets can be controlled continuously by adjusting the molar ratio of the starting materials. The solubility limit is x ∼ 0.20 based on the cell volume. In the 0.00 ≤ x ≤ 0.20 range, the band gap energy, magnetic moment, and Weiss temperature change systematically with x. The charge density of the (Mn,Co)O{sub 2} layer is independent of x (i.e., [(Mn,Co)O{sub 2}]{sup 0.2−}) and the cobalt ions are trivalent in low-spin state.

  15. A mild one-pot process for synthesising hydroxyapatite/biomolecule bone scaffolds for sustained and controlled antibiotic release.

    PubMed

    Hess, Ulrike; Hill, Sebastian; Treccani, Laura; Streckbein, Philipp; Heiss, Christian; Rezwan, Kurosch

    2015-02-01

    The release of active molecules or the control of nosocomial infections for improved osteoinduction is ideally addressed by a bone substitute material. For this purpose, the feasibility of a mild one-pot process is probed for incorporating directly active proteins and antibiotics in a hydroxyapatite (HAp) based scaffold. The effect of two serum model proteins, bovine serum albumin (BSA) and fibrinogen (FIB), on the microstructure, on selected mechanical properties as well as on degradation behaviour and on protein release are investigated. By protein incorporation, the porosity can be adjusted between 54 and 70% especially due to the foaming ability of BSA. The addition of 5 wt% FIB doubles the biaxial flexural strength up to 6 MPa in comparison to samples without proteins (3 MPa). Protein release experiments show that a rapid release takes place within the first days (between around 3% for FIB and 38% for BSA). As a possible application for osteomyelitis treatment, vancomycin and gentamicin were subsequently added instead of proteins to study their release behaviour and their antibacterial activity, respectively. A controlled antibiotic release was observed for a period of 18 d. By varying the protein type, mixture and quantity, the mechanical strength porosity as well as the protein release and calcium solubility can be controlled. Our studies underpin the suitability of this mild one-pot process as a promising simple-to-use platform for controlled local drug release and bone treatment. PMID:25594361

  16. A novel protocol for the one-pot borylation/Suzuki reaction provides easy access to hinge-binding groups for kinase inhibitors† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5ob01915j Click here for additional data file.

    PubMed Central

    Hooper, A.; Zambon, A.

    2016-01-01

    The one-pot borylation/Suzuki reaction is a very efficient means of accessing cross-coupling products of two aryl-halide partners that generally requires the use of specific catalysts or ligands and/or relatively long reaction times. This new microwave-assisted method provides a quick one-pot borylation/Suzuki reaction protocol that we applied to the synthesis of various bi- or poly-aryl scaffolds, including a variety of aryl and heteroaryl ring systems and the core frameworks of kinase inhibitors vemurafenib and GDC-0879. PMID:26620576

  17. Coupling field theory with mesoscopic dynamical simulations of multicomponent lipid bilayers.

    PubMed

    McWhirter, J Liam; Ayton, Gary; Voth, Gregory A

    2004-11-01

    A method for simulating a two-component lipid bilayer membrane in the mesoscopic regime is presented. The membrane is modeled as an elastic network of bonded points; the spring constants of these bonds are parameterized by the microscopic bulk modulus estimated from earlier atomistic nonequilibrium molecular dynamics simulations for several bilayer mixtures of DMPC and cholesterol. The modulus depends on the composition of a point in the elastic membrane model. The dynamics of the composition field is governed by the Cahn-Hilliard equation where a free energy functional models the coupling between the composition and curvature fields. The strength of the bonds in the elastic network are then modulated noting local changes in the composition and using a fit to the nonequilibrium molecular dynamics simulation data. Estimates for the magnitude and sign of the coupling parameter in the free energy model are made treating the bending modulus as a function of composition. A procedure for assigning the remaining parameters in the free energy model is also outlined. It is found that the square of the mean curvature averaged over the entire simulation box is enhanced if the strength of the bonds in the elastic network are modulated in response to local changes in the composition field. We suggest that this simulation method could also be used to determine if phase coexistence affects the stress response of the membrane to uniform dilations in area. This response, measured in the mesoscopic regime, is already known to be conditioned or renormalized by thermal undulations. PMID:15347594

  18. Compressible and monolithic microporous polymer sponges prepared via one-pot synthesis

    PubMed Central

    Lim, Yoonbin; Cha, Min Chul; Chang, Ji Young

    2015-01-01

    Compressible and monolithic microporous polymers (MPs) are reported. MPs were prepared as monoliths via a Sonogashira–Hagihara coupling reaction of 1,3,5-triethynylbenzene (TEB) with the bis(bromothiophene) monomer (PBT-Br). The polymers were reversibly compressible, and were easily cut into any form using a knife. Microscopy studies on the MPs revealed that the polymers had tubular microstructures, resembling those often found in marine sponges. Under compression, elastic buckling of the tube bundles was observed using an optical microscope. MP-0.8, which was synthesized using a 0.8:1 molar ratio of PBT-Br to TEB, showed microporosity with a BET surface area as high as 463 m2g–1. The polymer was very hydrophobic, with a water contact angle of 145° and absorbed 7–17 times its own weight of organic liquids. The absorbates were released by simple compression, allowing recyclable use of the polymer. MPs are potential precursors of structured carbon materials; for example, a partially graphitic material was obtained by pyrolysis of MP-0.8, which showed a similar tubular structure to that of MP-0.8. PMID:26534834

  19. One-Pot dry chemo-mechanical deconstruction for bioethanol production from sugarcane bagasse.

    PubMed

    Sambusiti, C; Licari, A; Solhy, A; Aboulkas, A; Cacciaguerra, T; Barakat, A

    2015-04-01

    The aim of this study was the application of an innovative dry chemo-mechanical pretreatment using different mechanical stresses to produce bioethanol from sugarcane bagasse (SB). The effect of different milling methods on physicochemical composition, enzymatic hydrolysis, bioethanol production and energy efficiency was also evaluated. SB was pretreated with NaOH and H3PO4 at high materials concentration (5 kg/L). Results indicate that vibratory milling (VBM) was more effective in the reduction of particles size and cellulose crystallinity compared to centrifugal (CM) and ball (BM) milling. NaOH pretreatment coupling to BM and VBM was preferred to enhance glucose yields and bioethanol production, while CM consumed less energy compared to BM and VBM. Moreover, the highest energy efficiency (η=0.116 kg glucose/kWh) was obtained with NaOH-CM. Therefore, the combination of dry NaOH and CM appears the most suitable and interesting pretreatment for the production of bioethanol from SB. PMID:25656863

  20. One-pot synthesis of L-Fructose using coupled multienzyme systems based on rhamnulose-1-phosphate aldolase.

    PubMed

    Franke, Dirk; Machajewski, Timothy; Hsu, Che-Chang; Wong, Chi-Huey

    2003-08-22

    Two methods have been developed for the highly efficient enzymatic synthesis of L-fructose: one is based on rhamnulose-1-phosphate aldolase and acid phosphatase using racemic glyceraldehyde and dihydroxyacetone phosphate as substrates; the other is to generate enantiomerically pure L-glyceraldehyde in situ from glycerol for the aldol reaction, using galactose oxidase catalyzed oxidation of glycerol in the presence of catalase. Using this four-enzyme system, enantiomerically pure L-fructose was obtained. Using the more expensive dihydroxyacetone phosphate, the yield was 55% after purification. PMID:12919060

  1. Carboxylic acid-grafted mesoporous material and its high catalytic activity in one-pot three-component coupling reaction

    SciTech Connect

    Gomes, Ruth; Bhaumik, Asim; Dutta, Saikat

    2014-11-01

    A new carboxylic acid functionalized mesoporous organic polymer has been synthesized via in situ radical polymerization of divinylbenzene and acrylic acid using a mesoporous silica as a seed during the polymerization process under solvothermal conditions. The mesoporous material MPDVAA-1 has been thoroughly characterized employing powder XRD, solid state {sup 13}C cross polarization magic angle spinning-nuclear magnetic resonance, FT-IR spectroscopy, N{sub 2} sorption, HR-TEM, and NH{sub 3} temperature programmed desorption-thermal conductivity detector (TPD-TCD) analysis to understand its porosity, chemical environment, bonding, and surface properties. The mesoporous polymer was used as a catalyst for a three comp onent Biginelli condensation between various aldehydes, β-keto esters, and urea/thioureas to give 3,4-dihydropyrimidine-2(1H)-ones. The reactions were carried out under conventional heating as well as solvent-free microwave irradiation of solid components, and in both the cases, the mesoporous polymer MPDVAA-1 proved to be a powerful, robust, and reusable catalyst with high catalytic efficiency.

  2. Carboxylic acid-grafted mesoporous material and its high catalytic activity in one-pot three-component coupling reaction

    NASA Astrophysics Data System (ADS)

    Gomes, Ruth; Dutta, Saikat; Bhaumik, Asim

    2014-11-01

    A new carboxylic acid functionalized mesoporous organic polymer has been synthesized via in situ radical polymerization of divinylbenzene and acrylic acid using a mesoporous silica as a seed during the polymerization process under solvothermal conditions. The mesoporous material MPDVAA-1 has been thoroughly characterized employing powder XRD, solid state 13C cross polarization magic angle spinning-nuclear magnetic resonance, FT-IR spectroscopy, N2 sorption, HR-TEM, and NH3 temperature programmed desorption-thermal conductivity detector (TPD-TCD) analysis to understand its porosity, chemical environment, bonding, and surface properties. The mesoporous polymer was used as a catalyst for a three comp onent Biginelli condensation between various aldehydes, β-keto esters, and urea/thioureas to give 3,4-dihydropyrimidine-2(1H)-ones. The reactions were carried out under conventional heating as well as solvent-free microwave irradiation of solid components, and in both the cases, the mesoporous polymer MPDVAA-1 proved to be a powerful, robust, and reusable catalyst with high catalytic efficiency.

  3. Evaluation of the metal uptake of several algae strains in a multicomponent matrix utilizing inductively coupled plasma emission spectrometry

    SciTech Connect

    Mahan, C.A.; Majidi, V.; Holcombe, J.A.

    1989-03-15

    Three freshwater heat-killed, lyophilized blue-green algae strains have been characterized as to their ability to accumulate heavy metals with a focus on the utilization of these algae as an analytical preconcentration technique. This study examines the metal uptake in several multicomponent mixtures by using inductively coupled plasma optical emission spectrometry (ICP-OES). Six milligrams of a pure strain of algae was added to 20-mL aliquots of buffered (pH 5.5-6.5) multielement solutions containing 0.1, 0.5, 1.0, 2.0, and 4.0 mg/L of K, Mg, Ca, Fe, Sr, Co, Cu, Mn, Ni, V, Zn, As, Cd, Mo, Pb, and Se. All three algae strains exhibit relatively high adsorption affinities for Fe, Pb, and Cu, with uptake between 70 and 98% at the 4 ppm concentration level. Biosorption occurs for essentially every element with the relative affinities decreasing in the order Pb greater than Fe greater than Cu greater than Cd greater than Zn greater than Mn greater than Mo greater than Sr greater than Ni greater than V greater than Se greater than As greater than Co for Chlorella pyrenoidosa at the 4 mg/L concentration level. Although some minor differences were seen, the other algae strains (Stichococcus bacillaris and Chlamydomonas reinharti) displayed similar adsorption behavior over the concentration range studied, indicating similar cell wall binding sites. Langmuirian isotherms exhibited a minimum of two slopes over the concentration range of 0.1-4.0 mg/L, indicating the probable existence of at least two adsorption mechanisms.

  4. One-pot non-enzymatic formation of firefly luciferin in a neutral buffer from p-benzoquinone and cysteine

    PubMed Central

    Kanie, Shusei; Nishikawa, Toshio; Ojika, Makoto; Oba, Yuichi

    2016-01-01

    Firefly luciferin, the substrate for the bioluminescence reaction of luminous beetles, possesses a benzothiazole ring, which is rare in nature. Here, we demonstrate a novel one-pot reaction to give firefly luciferin in a neutral buffer from p-benzoquinone and cysteine without any synthetic reagents or enzymes. The formation of firefly luciferin was low in yield in various neutral buffers, whereas it was inhibited or completely prevented in acidic or basic buffers, in organic solvents, or under a nitrogen atmosphere. Labelling analysis of the firefly luciferin using stable isotopic cysteines showed that the benzothiazole ring was formed via the decarboxylation and carbon-sulfur bond rearrangement of cysteine. These findings imply that the biosynthesis of firefly luciferin can be developed/evolved from the non-enzymatic production of firefly luciferin using common primary biosynthetic units, p-benzoquinone and cysteine. PMID:27098929

  5. Synthesis and magnetic properties of flower-like FeCo particles through a one pot polyol process.

    PubMed

    Karipoth, Prakash; Thirumurugan, Arun; Justin Joseyphus, R

    2013-08-15

    FeCo alloys of various compositions with flower-like morphology were synthesized using a unique one pot polyol process. The morphology of Fe particles was cubic, whereas the FeCo particles showed flower-like morphology, with more petals for the Co rich FeCo. The average particle size varied from 120 to 155 nm depending on the composition of the alloy. The Curie temperature as determined by thermomagnetic analysis was 985°C for Fe67Co33 and 939°C for the Fe36Co64 samples. Their corresponding bcc to fcc phase transformation temperatures were 985 and 825°C, respectively. Coercivity up to 511Oe was observed due to the shape anisotropy arising out of the flower-like morphology compared to the usual cubic or spherical morphologies. Post-annealing studies showed that Fe67Co33 is more stable compared to other compositions. PMID:23706584

  6. One-Pot Synthesis of Benzene-Fused Medium-Ring Ketones: Gold Catalysis-Enabled Enolate Umpolung Reactivity.

    PubMed

    Xu, Zhou; Chen, Hongyi; Wang, Zhixun; Ying, Anguo; Zhang, Liming

    2016-05-01

    Enolate umpolung reactivities offer valuable and potentially unique alternatives over the enolate counterparts for the construction of ubiquitous carbonyl compounds. We disclose here that N-alkenoxypyridinium salts, generated readily upon gold-catalyzed additions of protonated pyridine N-oxide to C-C triple bonds of unactivated terminal alkynes, display versatile enolate umpolung chemistry upon heating and react with tethered arene nucleophiles in an SN2' manner. In a synthetically efficient one-pot, two-step process, this chemistry enables expedient preparation of valuable benzo-fused seven-/eight-membered cyclic ketones, including those of O-/N-heterocycles, from easily accessible aryl-substituted linear alkyne substrates. The reaction yields can be up to 87%. PMID:27082456

  7. One-pot synthesis of fluorescent DHLA-stabilized Cu nanoclusters for the determination of H2O2.

    PubMed

    Zhou, Tingyao; Yao, Qiuhong; Zhao, Tingting; Chen, Xi

    2015-08-15

    A facile one-pot approach has been developed to prepare orange-emitting Cu nanoclusters (NCs) using tetrakis(hydroxymethyl)phosphonium chloride as a reducing agent and lipoic acid as a capping agent under an alkaline medium at room temperature. The as-prepared Cu NCs exhibited excellent water solubility, large Stokes shift, long lifetime and good dispersion. After the addition of polyvinyl pyrrolidone, the fluorescence intensity of dihydrolipoic acid-stabilized Cu NCs (DHLA-Cu NCs) was greatly enhanced, and their fluorescence signal remained stable for 5 weeks storage in the dark at room temperature. Based on H2O2-induced fluorescence quenching, DHLA-Cu NCs showed high sensitivity and selectivity for the detection of H2O2 in aqueous solution with a detection limit of 0.3μM, and were applied successfully to the detection of H2O2 in human urine samples. PMID:25966384

  8. One pot preparation of silver nanoparticles decorated TiO2 mesoporous microspheres with enhanced antibacterial activity.

    PubMed

    Chen, Yuemei; Deng, Yuanming; Pu, Yitao; Tang, Bijun; Su, Yikun; Tang, Jiaoning

    2016-08-01

    We report a simple "one-pot" solvothermal preparation of silver nanoparticles (Ag NPs) decorated mesoporous titania (TiO2) microspheres as an effective antibacterial agent. TBOT as Ti source was hydrolyzed and crystallized in media composed of acetic acid and ethanol, in which esterification catalyzed by TBOT occurred for in-situ "controlled water release". AgNO3 as Ag source was reduced by ethanol to form Ag NPs embedded in the TiO2 microspheres. The effect of AgNO3 and HAc on the morphology of Ag/TiO2 was investigated. The Ag/TiO2 with various Ag content showed excellent antibacterial activities with extremely low minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Escherichia coli and Staphylococcus aureus when compared with colloidal Ag NPs. PMID:27157724

  9. One-Pot Solvothermal Synthesis of Bi4V2O11 as A New Solar Water Oxidation Photocatalyst

    NASA Astrophysics Data System (ADS)

    Jiang, Zaiyong; Liu, Yuanyuan; Li, Mengmeng; Jing, Tao; Huang, Baibiao; Zhang, Xiaoyang; Qin, Xiaoyan; Dai, Ying

    2016-03-01

    Bi4V2O11 was prepared via a one-pot solvothermal method and characterized via XRD, Raman, XPS, Electrochemical impedance spectroscopy. The as-prepared Bi4V2O11 sample displays excellent photocatalytic activity towards oxygen evolution under light irradiation. The hierarchical structure is in favour of the spatial separation of photogenerated electrons and holes. Furthermore, the internal polar field also plays a role in improving the charge separation. Both of the two results are responsible for excellent activity of O2 evolution. The resulting hierarchical Bi4V2O11 sample should be very promising photocatalyst for the application of photocatalytic O2 evolution in the future.

  10. One-pot multiple reactions: asymmetric synthesis of 2,6-cis-disubstituted piperidine alkaloids from chiral aziridine.

    PubMed

    Yadav, Nagendra Nath; Choi, Jihye; Ha, Hyun-Joon

    2016-07-01

    A divergent, new, and highly stereoselective synthesis of cis-2,6-disubstituted piperidine natural products including isosolenopsins, deoxocassine, and spectaline was achieved from chiral aziridine decorated with appropriate alkyl chains for isosolenopsins or alkynyl groups for deoxocassine and spectaline at C2. The characteristic feature of this synthesis is one-pot sequential reactions under atmospheric hydrogen including the reduction of alkyne (for deoxocassine and spectaline), reductive ring-opening of aziridine, debenzylation, and intramolecular reductive amination in high yields. The prerequisite aziridines were elaborated from commercially available (2S)-hydroxymethylaziridine through oxidation, Wittig olefination, and the Grignard reaction for isosolenopsins or substrate-controlled lithium alkynylate addition for deoxocassine and spectaline. PMID:27189444

  11. Facile and efficient one-pot synthesis of 2-arylbenzoxazoles using hydrogen tetrachloroaurate as catalyst under oxygen atmosphere*

    PubMed Central

    Liu, Yun-kui; Mao, Da-jie; Lou, Shao-jie; Qian, Jian-qiang; Xu, Zhen-yuan

    2009-01-01

    In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which were directly synthesized from 2-aminophenol and aldehydes catalyzed by hydrogen tetrachloroaurate (HAuCl4·4H2O) under an oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant. PMID:19489113

  12. One-Pot Green Synthesis and Bioapplication of l-Arginine-Capped Superparamagnetic Fe3O4 Nanoparticles

    NASA Astrophysics Data System (ADS)

    Lai, Yongchao; Yin, Weiwei; Liu, Jinting; Xi, Rimo; Zhan, Jinhua

    2010-02-01

    Water-soluble l-arginine-capped Fe3O4 nanoparticles were synthesized using a one-pot and green method. Nontoxic, renewable and inexpensive reagents including FeCl3, l-arginine, glycerol and water were chosen as raw materials. Fe3O4 nanoparticles show different dispersive states in acidic and alkaline solutions for the two distinct forms of surface binding l-arginine. Powder X-ray diffraction and X-ray photoelectron spectroscopy were used to identify the structure of Fe3O4 nanocrystals. The products behave like superparamagnetism at room temperature with saturation magnetization of 49.9 emu g-1 and negligible remanence or coercivity. In the presence of 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride, the anti-chloramphenicol monoclonal antibodies were connected to the l-arginine-capped magnetite nanoparticles. The as-prepared conjugates could be used in immunomagnetic assay.

  13. One-pot non-enzymatic formation of firefly luciferin in a neutral buffer from p-benzoquinone and cysteine.

    PubMed

    Kanie, Shusei; Nishikawa, Toshio; Ojika, Makoto; Oba, Yuichi

    2016-01-01

    Firefly luciferin, the substrate for the bioluminescence reaction of luminous beetles, possesses a benzothiazole ring, which is rare in nature. Here, we demonstrate a novel one-pot reaction to give firefly luciferin in a neutral buffer from p-benzoquinone and cysteine without any synthetic reagents or enzymes. The formation of firefly luciferin was low in yield in various neutral buffers, whereas it was inhibited or completely prevented in acidic or basic buffers, in organic solvents, or under a nitrogen atmosphere. Labelling analysis of the firefly luciferin using stable isotopic cysteines showed that the benzothiazole ring was formed via the decarboxylation and carbon-sulfur bond rearrangement of cysteine. These findings imply that the biosynthesis of firefly luciferin can be developed/evolved from the non-enzymatic production of firefly luciferin using common primary biosynthetic units, p-benzoquinone and cysteine. PMID:27098929

  14. Simple one-pot preparation of water-soluble, cysteine-reactive cyanine and merocyanine dyes for biological imaging.

    PubMed

    Toutchkine, Alexei; Nguyen, Dan-Vinh; Hahn, Klaus M

    2007-01-01

    A simple one-pot-procedure for preparation of protein-reactive, water-soluble merocyanine and cyanine dyes has been developed. The 1-(3-ammoniopropyl)-2,3,3-trimethyl-3H-indolium-5-sulfonate bromide (1) was used as a common starting intermediate. The method allows easy preparation of dyes with chloro- and iodoacetamide side chains for covalent attachment to cysteine. By placing a sulfonato group directly on the dye fluorophore system, dyes with high fluorescence quantum yields in water were generated. Both iodo- and chloroacetamido derivatives were shown to be useful in protein labeling. Less reactive chloroacetamides will be preferential for selective labeling of the most reactive cysteines. PMID:17542551

  15. One-Pot Solvothermal Synthesis of Bi4V2O11 as A New Solar Water Oxidation Photocatalyst

    PubMed Central

    Jiang, Zaiyong; Liu, Yuanyuan; Li, Mengmeng; Jing, Tao; Huang, Baibiao; Zhang, Xiaoyang; Qin, Xiaoyan; Dai, Ying

    2016-01-01

    Bi4V2O11 was prepared via a one-pot solvothermal method and characterized via XRD, Raman, XPS, Electrochemical impedance spectroscopy. The as-prepared Bi4V2O11 sample displays excellent photocatalytic activity towards oxygen evolution under light irradiation. The hierarchical structure is in favour of the spatial separation of photogenerated electrons and holes. Furthermore, the internal polar field also plays a role in improving the charge separation. Both of the two results are responsible for excellent activity of O2 evolution. The resulting hierarchical Bi4V2O11 sample should be very promising photocatalyst for the application of photocatalytic O2 evolution in the future. PMID:26947126

  16. One-pot process combining transesterification and selective hydrogenation for biodiesel production from starting material of high degree of unsaturation.

    PubMed

    Yang, Ru; Su, Mengxing; Li, Min; Zhang, Jianchun; Hao, Xinmin; Zhang, Hua

    2010-08-01

    A one-pot process combining transesterification and selective hydrogenation was established to produce biodiesel from hemp (Cannabis sativa L.) seed oil which is eliminated as a potential feedstock by a specification of iodine value (IV; 120 g I(2)/100g maximum) contained in EN 14214. A series of alkaline earth metal oxides and alkaline earth metal supported copper oxide were prepared and tested as catalysts. SrO supported 10 wt.% CuO showed the superior catalytic activity for transesterification with a biodiesel yield of 96% and hydrogenation with a reduced iodine value of 113 and also exhibited a promising selectivity for eliminating methyl linolenate and increasing methyl oleate without rising methyl stearate in the selective hydrogenation. The fuel properties of the selective hydrogenated methyl esters are within biodiesel specifications. Furthermore, cetane numbers and iodine values were well correlated with the compositions of the hydrogenated methyl esters according to degrees of unsaturation. PMID:20231090

  17. One pot in situ growth of gold nanoparticles on amine-modified graphene oxide and their high catalytic properties

    NASA Astrophysics Data System (ADS)

    Ju, Yuyun; Li, Xi; Feng, Jie; Ma, Yanhua; Hu, Jing; Chen, Xingguo

    2014-10-01

    In this work, one pot strategy was proposed for in situ growth of Au nanoparticles (Au NPs) on the surface of amine-modified graphene oxide (GO@NH2) nanosheets. Au NPs were generated via an in situ reduction of Au3+ by Cu+ which was linked to the surface of GO@NH2 nanosheets through inorganic grafting. The initial Au NPs then served as seed for subsequent particle growth. The as-obtained GO@NH2-Au nanocomposites (GO@NH2-Au NCs) exhibited high catalytic activity for the degradation of 4-nitrophenol, which was a refractory pollutant that occur in industrial waste water. The catalytic efficiency was examined by turnover frequency (TOF). It was calculated to be 595 h-1, which was higher than that of other Au catalysts. Furthermore, the as-prepared catalyst showed high cycle stabilization during the catalytic reduction.

  18. One-pot synthesis of highly luminescent CdTe/CdS core/shell nanocrystals in aqueous phase

    NASA Astrophysics Data System (ADS)

    Gu, Zhenyu; Zou, Lei; Fang, Zheng; Zhu, Weihong; Zhong, Xinhua

    2008-04-01

    Surface passivation of nanocrystals with suitable organic or inorganic materials is key to improving the photoluminescence (PL) efficiency and stability of nanocrystals. Although the hot-injection organometallic approach is a powerful tool to achieve different kinds of core/shell structures, direct synthesis of such structures in aqueous phase, which bears many advantages such as biocompatibility, water-solubility, environment-friendliness, and cheapness, is less often reported. Herein we present a facile approach for the one-pot preparation of a water-soluble core/shell structure with CdTe cores packed in a CdS shell in aqueous phase. In comparison with plain CdTe nanocrystals, the PL efficiency of the obtained CdTe/CdS core/shell structure can approach about 75%. The stability of the core/shell structure to UV irradiation and oxidation is also improved.

  19. One-pot synthesis of MWW zeolite nanosheets using a rationally designed organic structure-directing agent

    PubMed Central

    Luo, Helen Y.; Michaelis, Vladimir K.; Hodges, Sydney; Griffin, Robert G.

    2015-01-01

    A new material MIT-1 comprised of delaminated MWW zeolite nanosheets is synthesized in one-pot using a rationally designed organic structure-directing agent (OSDA). The OSDA is comprised of a hydrophilic head segment that resembles the OSDA used to synthesize the zeolite precursor MCM22(P), a hydrophobic tail segment that resembles the swelling agent used to swell MCM22(P), and a di-quaternary ammonium linker that connects both segments. MIT-1 features high crystallinity and surface areas exceeding 500 m2g−1, and can be synthesized over a wide synthesis window that includes Si/Al ratios ranging from 13 to 67. Characterization data reveal high mesoporosity and acid strength with no detectable amorphous silica phases. Compared to MCM-22 and MCM-56, MIT-1 shows a three-fold increase in catalytic activity for the Friedel-Crafts alkylation of benzene with benzyl alcohol. PMID:26478803

  20. MOFs as multifunctional catalysts: one-pot synthesis of menthol from citronellal over a bifunctional MIL-101 catalyst.

    PubMed

    Cirujano, F G; Llabrés i Xamena, F X; Corma, A

    2012-04-14

    A bifunctional MOF catalyst containing coordinatively unsaturated Cr(3+) sites and palladium nanoparticles (Pd@MIL-101) has been used for the cyclization of citronellal to isopulegol and for the one-pot tandem isomerization/hydrogenation of citronellal to menthol. The MOF was found to be stable under the reaction conditions used, and the results obtained indicate that the performance of this bifunctional solid catalyst is comparable with other state-of-the-art materials for the tandem reaction: Full citronellal conversion was attained over Pd@MIL-101 in 18 h, with 86% selectivity to menthols and a diastereoselectivity of 81% to the desired (-)-menthol, while up to 30 h were necessary for attaining similar values over Ir/H-beta under analogous reaction conditions. PMID:22382815

  1. A simple one-pot strategy to platinum-palladium@palladium core-shell nanostructures with high electrocatalytic activity

    NASA Astrophysics Data System (ADS)

    Lv, Jing-Jing; Zheng, Jie-Ning; Wang, Ying-Ying; Wang, Ai-Jun; Chen, Li-Li; Feng, Jiu-Ju

    2014-11-01

    Well-defined platinum-palladium@palladium core-shell nanospheres (PtPd@Pd NSs) are synthesized by a facile one-pot solution approach using N-methylimidazole and poly(vinyl pyrrolidone) (PVP) as directing and capping agents, respectively, without using any seed, template, or organic solvent. The coexistence of the precursors, N-methylimidazole, PVP, and reaction temperature has great effects on the final morphology. Thus-prepared nanocomposites display an improved electrocatalytic activity for oxygen reduction reaction (ORR) in acidic media, methanol and ethylene glycol oxidation reaction in alkaline media, compared with Pt nanoparticles, Pd nanoparticles, commercial Pt black and Pd black catalysts. This method may direct a general orientation for shape control synthesis of functional bimetallic nanocrystals as promising electrocatalysts in direct alcohol fuel cells (DAFCs).

  2. One-pot aqueous synthesis of gadolinium doped CdTe quantum dots with dual imaging modalities.

    PubMed

    Jiang, Chunli; Shen, Zhitao; Luo, Chunhua; Lin, Hechun; Huang, Rong; Wang, Yiting; Peng, Hui

    2016-08-01

    A facile one-pot strategy has been developed for the aqueous synthesis of Gd doped CdTe (Gd:CdTe) QDs as fluorescence and magnetic resonance imaging dual-modal agent. The prepared Gd:CdTe QDs showed narrow size distribution and the average size was less than 5nm. The amount of Gd(3+) dopant in Gd:CdTe QDs significantly affected the optical properties of obtained QDs. The highest PL QY for the prepared Gd:CdTe QDs was up to 42.5%. The QDs showed the weak toxicity and significant enhancement in MRI signal. The specific relaxivity value (r1) was determined to be 4.22mM(-1)s(-1). These properties make the prepared Gd:CdTe QDs be an effective dual-modal imaging agent and have great potential applications in biomedical field. PMID:27216651

  3. One-pot preparation of superparamagnetic attapulgite/Fe3O4/polydopamine nanocomposites for adsorption of methylene blue

    NASA Astrophysics Data System (ADS)

    Mu, Bin; Kang, Yuru; Zheng, Maosong; Wang, Aiqin

    2016-05-01

    Superparamagnetic attapulgite/Fe3O4/polydopamine nanocomposites have been facilely prepared by a one-pot process without the nitrogen protection, in which Fe(III) was served as both of the oxidant for dopamine and the precursor of Fe3O4 in the presence of attapulgite. The introduction of attapulgite can effectively induce the uniform encapsulation of polydopamine and Fe3O4 nanoparticles on the surface of attapulgite, preventing from the formation of the free aggregates of Fe3O4 nanoparticles. The as-prepared APT/Fe3O4/PANI nanocomposites can be used as an adsorbent for the removal of methylene blue, and the adsorption ratio toward 100 ppm of methylene blue could reach 95.8%.

  4. From racemic precursors to fully stereocontrolled products: one-pot synthesis of chiral α-amino lactones and lactams.

    PubMed

    You, Zhi-Hao; Chen, Ying-Han; Liu, Yan-Kai

    2016-07-14

    Substituted racemic lactols or cyclic hemiaminals were directly used as nucleophiles in enamine-based asymmetric amination reactions to access enantioenriched α-amino lactones or lactams via a one-pot sequence. The desired products, which are very important building blocks in organic synthesis but difficult to be prepared in the optically enriched form, could be afforded with two stereogenic centers in high yields with excellent enantioselectivities. Moreover, starting from the racemic precursors and catalyzed by the enantiomeric pair of the catalyst, all possible stereoisomeric products were discretely provided only after simple column chromatography. Additionally, this protocol provides facile access to several novel bicyclic carbamates, and such drug-like heterocyclic compounds should be potentially useful in medicinal chemistry. PMID:27270561

  5. Rapid Synthesis of CoSb3/GRAPHENE Nanocomposites by One-Pot Solvothermal Route and Their Electrochemical Properties

    NASA Astrophysics Data System (ADS)

    Zheng, Yun-Xiao; Xie, Jian; Liu, Shuang-Yu; Song, Wen-Tao; Zhu, Tie-Jun; Cao, Gao-Shao; Zhao, Xin-Bing

    2012-03-01

    A facile synthetic approach for CoSb3/graphene nanocomposite has been developed in this work. By adjusting Co/Sb molar ratio, reaction temperature, and reaction time, we found that nanocrystalline CoSb3 (5-10 nm) can form at a low temperature of 180°C and a short time of only 1 h via a one-pot solvothermal route. At the same time, graphite oxide can be reduced to graphene with uniformly loaded CoSb3 nanoparticles. The composites have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The nanocomposite shows improved cycling stability compared to bare CoSb3.

  6. One-Pot Synthesis of Aza-Diketopiperazines Enabled by Controlled Reactivity of N-Isocyanate Precursors.

    PubMed

    Ivanovich, Ryan A; Vincent-Rocan, Jean-François; Elkaeed, Eslam B; Beauchemin, André M

    2015-10-01

    A one-pot sequence for the synthesis of aza-diketopiperazines is reported, involving carbazate acylation with chloroacetyl chloride, SN2 with a primary amine, N-isocyanate formation, and cyclization. Nitrogen-substituted isocyanates (N-isocyanates) are a rare class of amphoteric isocyanate with high, but severely underdeveloped synthetic potential. This approach highlights that βN-acyl carbazates can act as blocked (masked) N-isocyanates, thus allowing a challenging intermolecular SN2 reaction of a primary amine to proceed while the N-isocyanate is "protected", and then cyclization once it is unmasked. Control experiments show that the alternate pathway--N-isocyanate substitution and then cyclization by an intramolecular SN2 reaction--is not operating. PMID:26394075

  7. A simple one pot purification of bacterial amylase from fermented broth based on affinity toward starch-functionalized magnetic nanoparticle.

    PubMed

    Paul, Tanima; Chatterjee, Saptarshi; Bandyopadhyay, Arghya; Chattopadhyay, Dwiptirtha; Basu, Semanti; Sarkar, Keka

    2015-08-18

    Surface-functionalized adsorbant particles in combination with magnetic separation techniques have received considerable attention in recent years. Selective manipulation on such magnetic nanoparticles permits separation with high affinity in the presence of other suspended solids. Amylase is used extensively in food and allied industries. Purification of amylase from bacterial sources is a matter of concern because most of the industrial need for amylase is met by microbial sources. Here we report a simple, cost-effective, one-pot purification technique for bacterial amylase directly from fermented broth of Bacillus megaterium utilizing starch-coated superparamagnetic iron oxide nanoparticles (SPION). SPION was prepared by co-precipitation method and then functionalized by starch coating. The synthesized nanoparticles were characterized by transmission electron microscopy (TEM), a superconducting quantum interference device (SQUID, zeta potential, and ultraviolet-visible (UV-vis) and Fourier-transform infrared (FTIR) spectroscopy. The starch-coated nanoparticles efficiently purified amylase from bacterial fermented broth with 93.22% recovery and 12.57-fold purification. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the molecular mass of the purified amylase was 67 kD, and native gel showed the retention of amylase activity even after purification. Optimum pH and temperature of the purified amylase were 7 and 50°C, respectively, and it was stable over a range of 20°C to 50°C. Hence, an improved one-pot bacterial amylase purification method was developed using starch-coated SPION. PMID:24840788

  8. One-pot preparation of a mixed-mode organic-silica hybrid monolithic capillary column and its application in determination of endogenous gibberellins in plant tissues.

    PubMed

    Zhang, Zheng; Hao, Yan-Hong; Ding, Jun; Xu, Sheng-Nan; Yuan, Bi-Feng; Feng, Yu-Qi

    2015-10-16

    A newly improved one-pot method, based on "thiol-ene" click chemistry and sol-gel approach in microemulsion system, was developed for the preparation of C8/PO(OH)2-silica hybrid monolithic capillary column. The prepared monolith possesses large specific surface area, narrow mesopore size distribution and high column efficiency. The monolithic column was demonstrated to have cation exchange/reversed-phase (CX/RP) mixed-mode retention for analytes on nano-liquid chromatography (nano-LC). On the basis of the developed nano-LC system with MS detector coupled to pipette tip solid phase extraction (PT-SPE) and derivatization process, we then realized simultaneous determination of 10 gibberellins (GAs) with low limits of detection (LODs, 0.003-0.025 ng/mL). Furthermore, 6 endogenous GAs in only 5mg rice leaves (fresh weight) were successfully detected and quantified. The developed PT-SPE-nano-LC-MS strategy may offer promising applications in the determination of low abundant bioactive molecules from complex matrix. PMID:26365908

  9. L-cysteine functionalized magnetic nanoparticles (LCMNP): a novel magnetically separable organocatalyst for one-pot synthesis of 2-amino-4H-chromene-3-carbonitriles in water.

    PubMed

    Khalafi-Nezhad, Ali; Nourisefat, Maryam; Panahi, Farhad

    2015-07-28

    In this study, L-cysteine was chemically grafted to magnetic nanoparticles in order to prepare a reusable magnetic material incorporating an amino acid moiety. For this purpose, silica-coated magnetic nanoparticles (Fe3O4@SiO2) were reacted with trimethoxy(vinyl)silane to produce vinyl-functionalized magnetic nanoparticles (VMNP). Reaction of a VMNP substrate with L-cysteine in the presence of azobisisobutyronitrile (AIBN) resulted in the production of L-cysteine-functionalized magnetic nanoparticles (LCMNP). The LCMNP material was characterized using different microscopy and spectroscopy techniques such as FT-IR, XRD, TEM, SEM, EDX, VSM, and elemental analysis. Also, LCMNP was analyzed by thermogravimetric analysis (TGA) in order to determine its thermal behavior. The applicability of the LCMNP material was evaluated in a three-component coupling reaction between a nucleophile, salicylaldehyde and malononitrile as the catalyst for one-pot synthesis of 2-amino-4H-chromene-3-carbonitrile derivatives. The catalyst system showed high catalytic activity in this process and target products were obtained in high isolated yields in water as a green solvent. The LCMNP catalyst was reusable in this reaction at least 7 times with no significant decrease in its catalytic activity. PMID:26098281

  10. An improved analysis of coupled multicomponent diffusion of divalent cations in aluminosilicate garnet: An experimental and numerical study

    NASA Astrophysics Data System (ADS)

    Borinski, S. A.; Chakraborty, S.; Hoppe, U.

    2010-12-01

    Garnets in natural rocks show a variety of compositional zoning. These zonings preserve memory of the thermal and growth histories of the minerals which could be retrieved if appropriate cation diffusion data were available. Coupled multicomponent diffusion of major divalent cations in aluminosilicate garnet has been studied experimentally e.g. in [1,2,3]. Diffusion coefficients were retrieved from experimentally induced concentration profiles assuming that (i) garnets behaved thermodynamically ideally at the high temperatures of the experiments and (ii) the convolution effect on microprobe analysis could be approximated by an equation for convolution effect of a profile with a single, constant diffusivity. Further, calculated and measured profiles were matched visually without any statistical criteria. We have now carried out diffusion experiments in a piston cylinder apparatus using diffusion couples made from homogeneous gem quality natural pyrope and almandine garnets. These were annealed within graphite capsules under nominally anhydrous conditions at 25-35 kbar, 1260-1400 °C. The resulting profiles were described by diffusion coefficient matrices that accounted for the effects of thermodynamic non-ideality using the garnet solution model of [4]. Convolution was calculated using a numerical scheme that did not require any assumption of constant D. And finally, results obtained from visual fitting were compared to those obtained by error minimization according to the Nelder-Mead downhill simplex method. We find that the visual and error minimization routines yield diffusion coefficients that are within a factor of two of each other. Further, it is shown that for some compositional ranges it is impossible to constrain tracer diffusion coefficients of certain elements. This needs to be consid-ered in future studies designed to determine diffusion coefficients. The effects of thermodynamic non-ideality and a more exact convolution correction are small, but when

  11. One-Pot Two-Step Multicomponent Process of Indole and Other Nitrogenous Heterocycles or Amines toward α-Oxo-acetamidines.

    PubMed

    Martinez-Ariza, Guillermo; McConnell, Nicholas; Hulme, Christopher

    2016-04-15

    A cesium carbonate promoted three-component reaction of N-H containing heterocycles, primary or secondary amines, arylglyoxaldehydes, and anilines is reported. The key step involves a tandem sequence of N-1 addition of a heterocycle or an amine to preformed α-iminoketones, followed by an air- or oxygen-mediated oxidation to form α-oxo-acetamidines. The scope of the reaction is enticingly broad, and this novel methodology is applied toward the synthesis of various polycyclic heterocycles. PMID:27020621

  12. One-pot synthesis and control of aqueous soluble and organic soluble carbon dots from a designable waterborne polyurethane emulsion

    NASA Astrophysics Data System (ADS)

    Gu, Jiangjiang; Hu, Donghua; Huang, Jin; Huang, Xin; Zhang, Qiuhong; Jia, Xudong; Xi, Kai

    2016-02-01

    Carbon dots (CDs) have a wide range of applications and have drawn great interest in the recent decade. The fabrication and control of CDs with different solubilities are still urgent problems for their practical use. In this paper, aqueous soluble and organic soluble CDs (ACDs, OCDs) were produced by one-pot hydrothermal treatment of a designable waterborne polyurethane (WPU) emulsion. The difference in the solubility and fluorescence of these two kinds of CDs was attributed to the various functional groups on the surface, which were derived from the different segment fragments formed by hydrothermal treatment of a block polymer. It was found that the yields of the ACDs and OCDs could be regulated by means of selecting different soft segments in WPU. The more hydrophobic soft segments could result in an increase of the OCDs and a decrease of the ACDs. While the soft segments were hydrophilic or hydrolysable under hydrothermal conditions, only ACDs were obtained. The ACDs had good fluorescence and showed low cytotoxicity for use in multicolour bio-imaging. The OCDs processed good solubility in a wide range of organic solvents and were suitable for preparing fluorescent composite films with polymers.Carbon dots (CDs) have a wide range of applications and have drawn great interest in the recent decade. The fabrication and control of CDs with different solubilities are still urgent problems for their practical use. In this paper, aqueous soluble and organic soluble CDs (ACDs, OCDs) were produced by one-pot hydrothermal treatment of a designable waterborne polyurethane (WPU) emulsion. The difference in the solubility and fluorescence of these two kinds of CDs was attributed to the various functional groups on the surface, which were derived from the different segment fragments formed by hydrothermal treatment of a block polymer. It was found that the yields of the ACDs and OCDs could be regulated by means of selecting different soft segments in WPU. The more

  13. Organic crystal-binding peptides: morphology control and one-pot formation of protein-displaying organic crystals

    NASA Astrophysics Data System (ADS)

    Niide, Teppei; Ozawa, Kyohei; Nakazawa, Hikaru; Oliveira, Daniel; Kasai, Hitoshi; Onodera, Mari; Asano, Ryutaro; Kumagai, Izumi; Umetsu, Mitsuo

    2015-11-01

    Crystalline assemblies of fluorescent molecules have different functional properties than the constituent monomers, as well as unique optical characteristics that depend on the structure, size, and morphological homogeneity of the crystal particles. In this study, we selected peptides with affinity for the surface of perylene crystal particles by exposing a peptide-displaying phage library in aqueous solution to perylene crystals, eluting the surface-bound phages by means of acidic desorption or liquid-liquid extraction, and amplifying the obtained phages in Escherichia coli. One of the perylene-binding peptides, PeryBPb1: VQHNTKYSVVIR, selected by this biopanning procedure induced perylene molecules to form homogenous planar crystal nanoparticles by means of a poor solvent method, and fusion of the peptide to a fluorescent protein enabled one-pot formation of protein-immobilized crystalline nanoparticles. The nanoparticles were well-dispersed in aqueous solution, and Förster resonance energy transfer from the perylene crystals to the fluorescent protein was observed. Our results show that the crystal-binding peptide could be used for simultaneous control of perylene crystal morphology and dispersion and protein immobilization on the crystals.Crystalline assemblies of fluorescent molecules have different functional properties than the constituent monomers, as well as unique optical characteristics that depend on the structure, size, and morphological homogeneity of the crystal particles. In this study, we selected peptides with affinity for the surface of perylene crystal particles by exposing a peptide-displaying phage library in aqueous solution to perylene crystals, eluting the surface-bound phages by means of acidic desorption or liquid-liquid extraction, and amplifying the obtained phages in Escherichia coli. One of the perylene-binding peptides, PeryBPb1: VQHNTKYSVVIR, selected by this biopanning procedure induced perylene molecules to form homogenous planar

  14. Zinc-oxide-silica-silver nanocomposite: Unique one-pot synthesis and enhanced catalytic and anti-bacterial performance.

    PubMed

    Kokate, Mangesh; Garadkar, Kalyanrao; Gole, Anand

    2016-12-01

    We describe herein a unique approach to synthesize zinc oxide-silica-silver (ZnO-SiO2-Ag) nanocomposite, in a simple, one-pot process. The typical process for ZnO synthesis by alkaline precipitation of zinc salts has been tweaked to replace alkali by alkaline sodium silicate. The free acid from zinc salts helps in the synthesis of silica nanoparticles, whereas the alkalinity of sodium silicate precipitates the zinc salts. Addition of silver ions into the reaction pot prior to addition of sodium silicate, and subsequent reduction by borohydride, gives additional functionality of metallic centres for catalytic applications. The synthesis strategy is based on our recent work typically involving acid-base type of cross-reactions and demonstrates a novel strategy to synthesize nanocomposites in a one-pot approach. Each component in the composite offers a unique feature. ZnO besides displaying mild catalytic and anti-bacterial behaviour is an excellent and a cheap 3-D support for heterogeneous catalysis. Silver nanoparticles enhance the catalytic & anti-bacterial properties of ZnO. Silica is an important part of the composite; which not only "glues" the two nanoparticles thereby stabilizing the nanocomposite, but also significantly enhances the surface area of the composite; which is an attractive feature of any catalyst composite. The nanocomposite is found to show excellent catalytic performance with very high turnover frequencies (TOFs) when studied for catalytic reduction of Rhodamine B (RhB) and 4-Nitrophenol (4-NP). Additionally, the composite has been tested for its anti-bacterial properties on three different bacterial strains i.e. E. coli, B. Cereus and Bacillus firmus. The mechanism for enhancement of catalytic performance has been probed by understanding the role of silica in offering accessibility to the catalyst via its porous high surface area network. The nanocomposite has been characterized by a host of different analytical techniques. The uniqueness of

  15. Exfoliated Pd/HNb3O8 nanosheet as highly efficient bifunctional catalyst for one-pot cascade reaction

    NASA Astrophysics Data System (ADS)

    Lee, Nahaeng; Chung, Young-Min

    2016-05-01

    Ultrathin two-dimensional metal oxide nanosheets have drawn attention as potential solid acid catalysts owing to their strong acidity, attributed to the bridged OH groups formed on the nanosheets. In this study, a new class of bifunctional acid-metal catalyst was realized by the deposition of Pd on layered niobium oxide (KNb3O8 and HNb3O8) or its exfoliated nanosheet (Pd/HNb3O8-NS) and applied to one-pot cascade deacetalization and hydrogenation. It was found that the acid strength of the support exerted a large influence not only on the promotion of the first deacetalization step, but also on the acceleration of the subsequent hydrogenation step. Comparative experiments using a series of Pd/HZSM-5 catalysts with different acidities reconfirmed the crucial role of acid strength on hydrogenation. However, the superior catalytic activity of Pd/HNb3O8-NS for hydrogenation compared to that of Pd/HZSM-5 of similar acidity suggests a more efficient ensemble effect of the strong acid sites with the nearby metal sites on the nanosheet surface. Among the catalysts used, Pd/HNb3O8-NS showed the best catalytic performance for one-pot cascade reaction affording the desired product (benzyl alcohol) in approximately 92% yield, which was 7.1 and 1.2 times higher than that of layered Pd/KNb3O8 or Pd/HNb3O8, respectively. The excellent catalytic performance of Pd/HNb3O8-NS may result from the characteristic features of nanosheets: (i) the synergistic cooperation between the bifunctional active sites and (ii) the two-dimensional open surface offering easier access of the reactants to the active sites. Although the use of NaBH4 as hydrogen source was effective in improving the initial reaction performance, the basic nature of NaBH4 adversely resulted in weakening the acid strength of the catalyst, and consequently led to a reduction in catalytic activity.

  16. Polyaniline-intercalated layered vanadium oxide nanocomposites-One-pot hydrothermal synthesis and application in lithium battery

    NASA Astrophysics Data System (ADS)

    Chen, Yuping; Yang, Gang; Zhang, Zihui; Yang, Xiaoyan; Hou, Wenhua; Zhu, Jun-Jie

    2010-10-01

    Polyaniline-intercalated layered vanadium oxide nanocomposites were successfully synthesized by an one-pot hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. The effects of reaction conditions, such as pH value of the precursor solution, reaction temperature and time, and the amount of aniline on the structure and morphology of the obtained samples, were systematically investigated. Based on the experimental results, an in situ intercalation-polymerization-exfoliation mechanism was put forward for the formation of layered nanocomposites. The application of the resulting layered nanocomposite as the cathode material in lithium battery was tested and the results showed that the polyaniline-intercalated layered vanadium oxide nanocomposite prepared at 140 °C had a good cycling performance and might act as a promising cathode material for high-energy-density rechargeable lithium batteries.Polyaniline-intercalated layered vanadium oxide nanocomposites were successfully synthesized by an one-pot hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. The effects of reaction conditions, such as pH value of the precursor solution, reaction temperature and time, and the amount of aniline on the structure and morphology of the obtained samples, were systematically investigated. Based on the experimental results, an in situ intercalation-polymerization-exfoliation mechanism was put forward for the formation of layered nanocomposites. The application of the

  17. Cooperative catalysis of noncompatible catalysts through compartmentalization: wacker oxidation and enzymatic reduction in a one-pot process in aqueous media.

    PubMed

    Sato, Hirofumi; Hummel, Werner; Gröger, Harald

    2015-04-01

    A Wacker oxidation using CuCl/PdCl2 as a catalyst system was successfully combined with an enzymatic ketone reduction to convert styrene enantioselectively into 1-phenylethanol in a one-pot process, although the two reactions conducted in aqueous media are not compatible due to enzyme deactivation by Cu ions. The one-pot feasibility was achieved via compartmentalization of the reactions. Conducting the Wacker oxidation in the interior of a polydimethylsiloxane thimble enables diffusion of only the organic substrate and product into the exterior where the biotransformation takes place. Thus, the Cu ions detrimental to the enzyme are withheld from the reaction media of the biotransformation. In this one-pot process, which formally corresponds to an asymmetric hydration of alkenes, a range of 1-arylethanols were formed with high conversions and 98-99 % ee. In addition, the catalyst system of the Wacker oxidation was recycled 15 times without significant decrease in conversion. PMID:25704961

  18. One-pot solventless preparation of PEGylated black phosphorus nanoparticles for photoacoustic imaging and photothermal therapy of cancer.

    PubMed

    Sun, Caixia; Wen, Ling; Zeng, Jianfeng; Wang, Yong; Sun, Qiao; Deng, Lijuan; Zhao, Chongjun; Li, Zhen

    2016-06-01

    Black phosphorus (BP) nanostructures such as nanosheets and nanoparticles have attracted considerable attention in recent years due to their unique properties and great potential in various physical, chemical, and biological fields. In this article, water-soluble and biocompatible PEGylated BP nanoparticles with a high yield were prepared by one-pot solventless high energy mechanical milling technique. The resultant BP nanoparticles can efficiently convert near infrared (NIR) light into heat, and exhibit excellent photostability, which makes them suitable as a novel nanotheranostic agent for photoacoustic (PA) imaging and photothermal therapy of cancer. The in-vitro results demonstrate the excellent biocompatibility of PEGylated BP nanoparticles, which can be used for photothermal ablation of cancer cells under irradiation with NIR light. The in-vivo PA images demonstrate that these BP nanoparticles can be efficiently accumulated in tumors through the enhanced permeability retention effect. The resultant BP nanoparticles can be further utilized for photothermal ablation of tumors by irradiation with NIR light. The tumor-bearing mice were completely recovered after photothermal treatment with BP nanoparticles, in comparison with mice from control groups. Our research highlights the great potential of PEGylated BP nanoparticles in detection and treatment of cancer. PMID:27017578

  19. Sliding over the Blocks in Enzyme-Free RNA Copying – One-Pot Primer Extension in Ice

    PubMed Central

    Löffler, Philipp M. G.; Groen, Joost; Dörr, Mark; Monnard, Pierre-Alain

    2013-01-01

    Template-directed polymerization of RNA in the absence of enzymes is the basis for an information transfer in the ‘RNA-world’ hypothesis and in novel nucleic acid based technology. Previous investigations established that only cytidine rich strands are efficient templates in bulk aqueous solutions while a few specific sequences completely block the extension of hybridized primers. We show that a eutectic water/ice system can support Pb2+/Mg2+-ion catalyzed extension of a primer across such sequences, i.e. AA, AU and AG, in a one-pot synthesis. Using mixtures of imidazole activated nucleotide 5′-monophosphates, the two first “blocking” residues could be passed during template-directed polymerization, i.e., formation of triply extended products containing a high fraction of faithful copies was demonstrated. Across the AG sequence, a mismatch sequence was formed in similar amounts to the correct product due to U·G wobble pairing. Thus, the template-directed extension occurs both across pyrimidine and purine rich sequences and insertions of pyrimidines did not inhibit the subsequent insertions. Products were mainly formed with 2′-5′-phosphodiester linkages, however, the abundance of 3′–5′-linkages was higher than previously reported for pyrimidine insertions. When enzyme-free, template-directed RNA polymerization is performed in a eutectic water ice environment, various intrinsic reaction limitations observed in bulk solution can then be overcome. PMID:24058695

  20. One-Pot Hydrothermal Synthesis of Magnetite Prussian Blue Nano-Composites and Their Application to Fabricate Glucose Biosensor.

    PubMed

    Jomma, Ezzaldeen Younes; Ding, Shou-Nian

    2016-01-01

    In this work, we presented a simple method to synthesize magnetite Prussian blue nano-composites (Fe₃O₄-PB) through one-pot hydrothermal process. Subsequently, the obtained nano-composites were used to fabricate a facile and effective glucose biosensor. The obtained nanoparticles were characterized using transmission electron microscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, UV-vis absorbance spectroscopy, cyclic voltammetry and chronoamperometry. The resultant Fe₃O₄-PB nanocomposites have magnetic properties which could easily controlled by an external magnetic field and the electro-catalysis of hydrogen peroxide. Thus, a glucose biosensor based on Fe₃O₄-PB was successfully fabricated. The biosensor showed super-electrochemical properties toward glucose detection exhibiting fast response time within 3 to 4 s, low detection limit of 0.5 µM and wide linear range from 5 µM to 1.2 mM with sensitivity of 32 µA∙mM(-1)∙cm(-2) and good long-term stability. PMID:26901204

  1. One-pot, water-based and high-yield synthesis of tetrahedral palladium nanocrystal decorated graphene

    NASA Astrophysics Data System (ADS)

    Fu, Gengtao; Tao, Lin; Zhang, Min; Chen, Yu; Tang, Yawen; Lin, Jun; Lu, Tianhong

    2013-08-01

    This paper reports a facile, water-based and one-pot synthesis of tetrahedral Pd nanocrystals (Pd-TNPs) with high yield and good size monodispersity supported on reduced graphene oxide (RGO) nanosheets via a co-chemical reduction method. The key synthetic strategy employed a positively charged polyallylamine-PdII complex (PAH-PdII) with un-coordinated amine groups as a linker molecule to immobilize PdII species on the negatively charged graphene oxide (GO) surface through electrostatic interaction. As characterized by transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) techniques, well-defined Pd-TNPs with an average size of 9 nm were uniformly distributed on the RGO surface. The as-prepared Pd-TNPs/RGO nanohybrid with excellent colloidal stability in aqueous solution exhibits superior catalytic activity towards the degradation of methylene blue (MB) compared to both unsupported Pd-TNPs and Pd black. Thus, the resultant Pd-TNPs/RGO nanohybrid, as a promising heterogeneous catalyst, might have wide potential applications in water-based catalysis systems for the future.

  2. One-Pot Synthesis of SnO2/C Nanocapsules Composites as Anode Materials for Lithium-Ion Batteries.

    PubMed

    Yang, Lina; Chen, Kexun; Dong, Tao; Wang, Zhao; Li, Guomin; Zhang, Yanling; Zhang, Lipeng

    2016-02-01

    In this work, we demonstrate a facile route for the synthesis of nanostructured SnO2/C composites for lithium-ion batteries. The anode materials were prepared via a one-pot solvothermal approach and then calcination in a highly pure nitrogen atmosphere. The composited was composed of amor- phous carbon and nanocrystalline SnO2 by the X-ray diffraction (XRD) analysis, and the content of carbon was calculated according to the thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) images revealed that the diameter of these as-prepared spheres varied from 50 to 60 nm. A systematic study has been carried out to examine the effect of carbon content upon lithium-ion battery performance. The electrochemical results showed that SnO2/C nanocomposite could achieve 1197.5 mAh/g reversible capacity and 55.11% initial coulombic efficiency, and 190% capacity retention after 50 cycles compared to the SnO2 nanoparticles of 940.6 mAh/g at a current density 0.2 C in the voltage range of 0.01-3.0 V. These improvements can be ascribed to the carbon, which can enhance the conductivity of SnO2, suppress the aggregation of active particles, and increase their structural stability during cycling. PMID:27433668

  3. Preparation of stable magnetic nanofluids containing Fe3O4@PPy nanoparticles by a novel one-pot route

    PubMed Central

    2011-01-01

    Stable magnetic nanofluids containing Fe3O4@Polypyrrole (PPy) nanoparticles (NPs) were prepared by using a facile and novel method, in which one-pot route was used. FeCl3·6H2O was applied as the iron source, and the oxidizing agent to produce PPy. Trisodium citrate (Na3cit) was used as the reducing reagent to form Fe3O4 NPs. The as-prepared nanofluid can keep long-term stability. The Fe3O4@PPy NPs can still keep dispersing well after the nanofluid has been standing for 1 month and no sedimentation is found. The polymerization reaction of the pyrrole monomers took place with Fe3+ ions as the initiator, in which these Fe3+ ions remained in the solution adsorbed on the surface of the Fe3O4 NPs. Thus, the core-shell NPs of Fe3O4@PPy were obtained. The particle size of the as-prepared Fe3O4@PPy can be easily controlled from 7 to 30 nm by the polymerization reaction of the pyrrole monomers. The steric stabilization and weight of the NPs affect the stability of the nanofluids. The as-prepared Fe3O4@PPy NPs exhibit superparamagnetic behavior. PMID:21711771

  4. Designing novel hybrid materials by one-pot co-condensation: from hydrophobic mesoporous silica nanoparticles to superamphiphobic cotton textiles.

    PubMed

    Pereira, C; Alves, C; Monteiro, A; Magén, C; Pereira, A M; Ibarra, A; Ibarra, M R; Tavares, P B; Araújo, J P; Blanco, G; Pintado, J M; Carvalho, A P; Pires, J; Pereira, M F R; Freire, C

    2011-07-01

    This work reports the synthesis and characterization of mesoporous silica nanoparticles (MSNs) functionalized with tridecafluorooctyltriethoxysilane (F13) and their in situ incorporation onto cotton textiles. The hybrid MSNs and the functional textiles were prepared by a one-pot co-condensation methodology between tetraethylorthosilicate (TEOS) and F13, with hexadecyltrimethylammonium chloride (CTAC) as the template and triethanolamine as the base. The influence of the F13 to TEOS molar ratio (1:10, 1:5 and 1:3) on the nanoparticle morphology, porosity, degree of functionalization, and hydro/oleophobic properties is discussed. The hybrid nanosilicas presented high colloidal stability and were spherical and monodispersed with average particle size of ∼45 nm. They also showed high surface areas, large pore volumes, and a wormhole-type mesoporous structure. The increase in the organosilane proportion during the co-condensation process led to a more radially branched wormhole-like mesoporosity, a decrease in the surface area, pore volume, and amount of surface silanol groups, and an enrichment of the surface with fluorocarbon moieties. These changes imparted hydrophobic and oleophobic properties to the materials, especially to that containing the highest F13 loading. Cotton textiles were coated with the F13-MSNs through an efficient and less time-consuming route. The combination between surface roughness and mesoporosity imparted by the MSNs, and the low surface energy provided by the organosilane resulted in superhydrophobic functional textiles. Moreover, the textile with the highest loading of fluorocarbon groups was superamphiphobic. PMID:21615151

  5. Fabrication of γ-MnS/rGO composite by facile one-pot solvothermal approach for supercapacitor applications

    NASA Astrophysics Data System (ADS)

    Li, Xianfu; Shen, Jianfeng; Li, Na; Ye, Mingxin

    2015-05-01

    γ-MnS/reduced graphene oxide (γ-MnS/rGO) composite was successfully fabricated via a facile one-pot solvothermal route using graphene oxide (GO), thioacetamide (TAA, CH3CSNH2) and MnCl2·4H2O as reactants. It reveals that TAA plays an important role in reducing GO and sulfurizing γ-MnS. The synthesized composite was characterized via X-ray diffraction and scanning electron microscopy for structural and morphological studies. Electrochemical performance was also investigated through cyclic voltammetry and galvanostatic charge-discharge. As for the application of supercapacitors, the γ-MnS/rGO composite shows a great value of 802.5 F g-1 at a current density of 5 A g-1. Furthermore, the capacitance of γ-MnS/rGO has no decrease of its initial values after 2000 cycles. The galvanostatic charge-discharge curve demonstrates the ideal capacitive behavior of γ-MnS/rGO composite electrodes.

  6. A One Pot Synthesis of Novel Bioactive Tri-Substitute-Condensed-Imidazopyridines that Targets Snake Venom Phospholipase A2.

    PubMed

    Anilkumar, Nirvanappa C; Sundaram, Mahalingam S; Mohan, Chakrabhavi Dhananjaya; Rangappa, Shobith; Bulusu, Krishna C; Fuchs, Julian E; Girish, Kesturu S; Bender, Andreas; Basappa; Rangappa, Kanchugarakoppal S

    2015-01-01

    Drugs such as necopidem, saripidem, alpidem, zolpidem, and olprinone contain nitrogen-containing bicyclic, condensed-imidazo[1,2-α]pyridines as bioactive scaffolds. In this work, we report a high-yield one pot synthesis of 1-(2-methyl-8-aryl-substitued-imidazo[1,2-α]pyridin-3-yl)ethan-1-onefor the first-time. Subsequently, we performed in silico mode-of-action analysis and predicted that the synthesized imidazopyridines targets Phospholipase A2 (PLA2). In vitro analysis confirmed the predicted target PLA2 for the novel imidazopyridine derivative1-(2-Methyl-8-naphthalen-1-yl-imidazo [1,2-α]pyridine-3-yl)-ethanone (compound 3f) showing significant inhibitory activity towards snake venom PLA2 with an IC50 value of 14.3 μM. Evidently, the molecular docking analysis suggested that imidazopyridine compound was able to bind to the active site of the PLA2 with strong affinity, whose affinity values are comparable to nimesulide. Furthermore, we estimated the potential for oral bioavailability by Lipinski's Rule of Five. Hence, it is concluded that the compound 3f could be a lead molecule against snake venom PLA2. PMID:26196520

  7. Facile one-pot synthesis of Pt/graphene-TiO2 hybrid catalyst with enhanced methanol electrooxidation performance

    NASA Astrophysics Data System (ADS)

    Zhao, Lei; Wang, Zhen-Bo; Liu, Jing; Zhang, Jing-Jia; Sui, Xu-Lei; Zhang, Li-Mei; Gu, Da-Ming

    2015-04-01

    Pt/graphene-TiO2 hybrid catalysts have been synthesized by a facile one-pot solvothermal method. The Structural properties of obtained Pt/graphene-TiO2 catalysts are characterized by X-ray diffraction (XRD), Energy dispersive analysis of X-ray (EDAX) and transmission electron microscopy (TEM).Interesting, TEM presents Pt nanoparticles seem preferentially to locate between TiO2 and graphene, forming the unique triple junctions structure. The electrochemical experimental results indicate that Pt/graphene-TiO2 catalyst exhibits 1.46 times higher activity for methanol electrooxidation than that of Pt/graphene and its stability is improved by 15% as compared with Pt/graphene. Moreover, performance of Pt/graphene-TiO2 hybrid catalyst is evaluated by the Single Fuel Cell Tests for the first time. Single fuel cell tests show the maximum power density of the direct methanol fuel cell using Pt/graphene-TiO2 as the anode catalyst is increased by 55% compared with that using Pt/graphene catalyst at the same operating conditions. The significantly enhanced electrochemical performance can be ascribed to (1) the synergetic effect between Pt, graphene and TiO2; (2) strong metal-support interaction (SMSI) between Pt nanoparticles and TiO2. These findings suggest their great potential applications in fuel cells.

  8. A Facile Route for Patterned Growth of Metal-Insulator Carbon Lateral Junction through One-Pot Synthesis.

    PubMed

    Park, Beomjin; Park, Jaesung; Son, Jin Gyeong; Kim, Yong-Jin; Yu, Seong Uk; Park, Hyo Ju; Chae, Dong-Hun; Byun, Jinseok; Jeon, Gumhye; Huh, Sung; Lee, Seoung-Ki; Mishchenko, Artem; Hyun, Seung; Lee, Tae Geol; Han, Sang Woo; Ahn, Jong-Hyun; Lee, Zonghoon; Hwang, Chanyong; Novoselov, Konstantin S; Kim, Kwang S; Hong, Byung Hee; Kim, Jin Kon

    2015-08-25

    Precise graphene patterning is of critical importance for tailor-made and sophisticated two-dimensional nanoelectronic and optical devices. However, graphene-based heterostructures have been grown by delicate multistep chemical vapor deposition methods, limiting preparation of versatile heterostructures. Here, we report one-pot synthesis of graphene/amorphous carbon (a-C) heterostructures from a solid source of polystyrene via selective photo-cross-linking process. Graphene is successfully grown from neat polystyrene regions, while patterned cross-linked polystyrene regions turn into a-C because of a large difference in their thermal stability. Since the electrical resistance of a-C is at least 2 orders of magnitude higher than that for graphene, the charge transport in graphene/a-C heterostructure occurs through the graphene region. Measurement of the quantum Hall effect in graphene/a-C lateral heterostructures clearly confirms the reliable quality of graphene and well-defined graphene/a-C interface. The direct synthesis of patterned graphene from polymer pattern could be further exploited to prepare versatile heterostructures. PMID:26144549

  9. One-pot synthesis of carbon dots-embedded molecularly imprinted polymer for specific recognition of sterigmatocystin in grains.

    PubMed

    Xu, Longhua; Fang, Guozhen; Pan, Mingfei; Wang, Xuefeng; Wang, Shuo

    2016-03-15

    A novel sensitive fluorescent sensor for determination of sterigmatocystin (ST), which was based on carbon dots-embedded molecularly imprinted polymer (CDs@MIP), was prepared by an efficient one-pot reaction. First, highly blue luminescent CDs were synthesized via a one-step reaction. Then, through a non-hydrolytic sol-gel process, MIP was formed on the CDs surface in the presence of 1,8-dihydroxyanthraquinone as an alternative template molecule to obtain CDs@MIP. The CDs acted as antennas for signal amplification and optical readout, and the MIP coated on the CDs surface provided specific binding sites for ST. The performance of CDs@MIP was compared with that of CDs embedded in non-imprinted polymer (CDs@NIP). CDs@MIP exhibited high selectivity and sensitivity toward ST. Under optimized conditions, the relative fluorescence intensity of CDs@MIP decreased linearly with the concentration of ST from 0.05 to 2.0 mgL(-1) with a detection limit of 0.019 mgL(-1) (S/N=3) and the precision for five replicate detections of 0.10 mgL(-1) ST was 2.31%. The sensor was also used to determine the content of ST in grains with satisfactory results. PMID:26544869

  10. One-pot synthesis of magnetite nanorods/graphene composites and its catalytic activity toward electrochemical detection of dopamine.

    PubMed

    Salamon, J; Sathishkumar, Y; Ramachandran, K; Lee, Yang Soo; Yoo, Dong Jin; Kim, Ae Rhan; Gnana Kumar, G

    2015-02-15

    Magnetite (Fe3O4) nanorods anchored over reduced graphene oxide (rGO) were synthesized through a one-pot synthesis method, where the reduction of GO and in-situ generation of Fe3O4 nanorods occurred concurrently. The average head and tail diameter of Fe3O4 nanorods anchored over the rGO matrix are found to be 32 and 11 nm, respectively, and morphology, structure and diameter of bare Fe3O4 nanorods were not altered even after the composite formation with rGO. The increased structural disorders and decrement in the sp(2) domains stimulated the high electrical conductivity and extended catalytic active sites for the prepared rGO/Fe3O4 nanocomposite. The constructed rGO/Fe3O4/GCE sensor exhibited excellent electrocatalytic activity toward the electrooxidation of dopamine (DA) with a quick response time of 6s, a wide linear range between 0.01 and 100.55 µM, high sensitivity of 3.15 µA µM(-1) cm(-2) and a lower detection limit of 7 nM. Furthermore, the fabricated sensor exhibited a practical applicability in the quantification of DA in urine samples with an excellent recovery rate. The excellent electroanalytical performances and straight-forward, surfactant and template free preparation method construct the rGO/Fe3O4 composite as an extremely promising material for the diagnosis of DA related diseases in biomedical applications. PMID:25240127

  11. One-pot synthesis of hierarchical Cu2O/Cu hollow microspheres with enhanced visible-light photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Hong, Tianjie; Tao, Feifei; Lin, Jiudong; Ding, Wei; Lan, Mingxuan

    2015-08-01

    The hierarchical Cu2O/Cu hollow microspheres have been fabricated by the one-pot solvothermal redox method, which is one-step approach without any surfactant and template. By using the HRTEM, XRD, XPS and UV-vis spectroscopy, the as-prepared product is composed of Cu2O and Cu with energy band gap of 1.72 eV. Based on the time-dependent experiments, the content of Cu2O and Cu compositions can be effectively controlled by adjusting the reaction time and a possible mechanism is proposed. In addition, using various dye molecules to stimulate pollutants, the hierarchical Cu2O/Cu hollow microspheres reacted for 8 h exhibit excellent visible-light photocatalytic activities, which is much higher than those of the Cu2O/Cu catalysts formed at the shorter reaction time, commercial Cu2O powder and the mixture of alone Cu2O and Cu. This enhanced photocatalytic performance makes these hierarchical Cu2O/Cu hollow microspheres a kind of efficient visible-light photocatalyst in removing some organic compounds in wastewater.

  12. A Facile One-Pot Synthesis of Au/Cu2O Nanocomposites for Nonenzymatic Detection of Hydrogen Peroxide

    NASA Astrophysics Data System (ADS)

    Chen, Ting; Tian, Liangliang; Chen, Yuan; Liu, Bitao; Zhang, Jin

    2015-06-01

    Au/Cu2O nanocomposites were successfully synthesized by a facile one-pot redox reaction without additional reducing agent under room temperature. The morphologies and structures of the as-prepared products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The electrocatalytic performance of Au/Cu2O nanocomposites towards hydrogen peroxide was evaluated by cyclic voltammetry (CV) and chronoamperometry (CA). The prepared Au/Cu2O nanocomposite electrode showed a wide linear range from 25 to 11.2 mM ( R = 0.9989) with a low detection limit of 1.05 μM ( S/ N = 3) and high sensitivity of 292.89 mA mM-1 cm-2. The enhanced performance for H2O2 detection can be attributed to the introduction of Au and the synergistic effect between Au and Cu2O. It is demonstrated that the Au/Cu2O nanocomposites material could be a promising candidate for H2O2 detection.

  13. One-pot template-free preparation of mesoporous TiO{sub 2} hollow spheres and their photocatalytic activity

    SciTech Connect

    Kang, Shizhao; Yin, Dieer; Li, Xiangqing; Li, Liang; Mu, Jin

    2012-11-15

    Highlights: ► Mesoporous TiO{sub 2} hollow spheres were prepared in a one-pot process. ► The process does not involve any templates and surfactants. ► The TiO{sub 2} hollow spheres display high photocatalytic activity. -- Abstract: Mesoporous TiO{sub 2} hollow spheres were prepared in a solvothermal process, which did not involve any templates and surfactants. Meanwhile, the photocatalytic activity of TiO{sub 2} hollow spheres was studied using methyl orange as a probe. The results indicate that the anatase TiO{sub 2} hollow spheres with mesoporous walls and high specific surface area (141 m{sup 2} g{sup −1}) can be obtained using this simple method. The mean diameter and wall thickness of spheres are about 700 nm and 90 nm, respectively. Moreover, the as-prepared TiO{sub 2} hollow spheres display high photocatalytic activity with 98% of degradation ratio of methyl orange after 30 min irradiation.

  14. One-Pot Hydrothermal Synthesis of Magnetite Prussian Blue Nano-Composites and Their Application to Fabricate Glucose Biosensor

    PubMed Central

    Jomma, Ezzaldeen Younes; Ding, Shou-Nian

    2016-01-01

    In this work, we presented a simple method to synthesize magnetite Prussian blue nano-composites (Fe3O4-PB) through one-pot hydrothermal process. Subsequently, the obtained nano-composites were used to fabricate a facile and effective glucose biosensor. The obtained nanoparticles were characterized using transmission electron microscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, UV-vis absorbance spectroscopy, cyclic voltammetry and chronoamperometry. The resultant Fe3O4-PB nanocomposites have magnetic properties which could easily controlled by an external magnetic field and the electro-catalysis of hydrogen peroxide. Thus, a glucose biosensor based on Fe3O4-PB was successfully fabricated. The biosensor showed super-electrochemical properties toward glucose detection exhibiting fast response time within 3 to 4 s, low detection limit of 0.5 µM and wide linear range from 5 µM to 1.2 mM with sensitivity of 32 µA∙mM−1∙cm−2 and good long-term stability. PMID:26901204

  15. In situ one-pot synthesis of graphene-polyaniline nanofiber composite for high-performance electrochemical capacitors

    NASA Astrophysics Data System (ADS)

    Jin, Yuhong; Fang, Mou; Jia, Mengqiu

    2014-07-01

    In this work, graphene-polyaniline nanofiber (G/PANI-F) composite is prepared through a new and one-pot method that includes the reduction of graphene oxide (GO) by aniline and then followed by in-situ polymerization. Aniline plays the two roles in this method: as a chemical reducing agent to reduce GO to graphene and as a monomer to prepare polyaniline nanofiber (PANI-F). Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectra, X-ray photoelectron spectroscopy and transmission electron microscopy are employed to confirm that GO can be reduced by aniline and PANI-F can be deposited on the surface of graphene. The electrochemical properties of G/PANI-F composite electrode are measured by using cyclic voltammetry, galvanostatic charge-discharge test and electrochemical impedance spectroscopy. The G/PANI-F composite electrode exhibits enhanced specific capacitance of 965 F g-1 at 0.5 A g-1 and the capacity retention is 90% after 2000 cycles.

  16. Rapid "one-pot" preparation of polymeric monolith via photo-initiated thiol-acrylate polymerization for capillary liquid chromatography.

    PubMed

    Bai, Jingyao; Wang, Hongwei; Ou, Junjie; Liu, Zhongshan; Shen, Yehua; Zou, Hanfa

    2016-06-21

    A facile approach was exploited for fast preparation of polymer-based monoliths in UV-transparent fused-silica capillaries via "one-pot" photo-initiated thiol-acrylate polymerization reaction of dipentaerythritolpenta-/hexaacrylate (DPEPA) and 1-octadecanethiol (ODT) in the presence of porogenic solvents (1-butanol and ethylene glycol). Due to relative insensitivity of oxygen inhibition in thiol-ene free-radical polymerization, the polymerization could be performed within 5 min. The effects of composition of prepolymerization solution on the morphology and permeability of poly(ODT-co-DPEPA) monoliths were investigated in detail by adjusting the content of monomer and binary porogen ratio. The physical properties of poly(ODT-co-DPEPA) monoliths were characterized by Fourier transform infrared spectroscopy (FT-IR), mercury intrusion porosimetry (MIP) and nitrogen adsorption/desorption measurement. The evaluation of chromatographic performance was carried out by capillary liquid chromatography (cLC). The results indicated that the poly(ODT-co-DPEPA) monolith was homogeneous and permeable, and also possessed a typical reversed-phase retention mechanism in cLC with high efficiency (∼75,000 N m(-1)) for separation of alkylbenzenes. Eventually, the further separation of tryptic digest of proteins by cLC tandem mass spectrometry (cLC-MS/MS) demonstrated its potential in the analysis of biological samples. PMID:27188321

  17. Safer one-pot synthesis of the ‘SHAPE’ reagent 1-methyl-7-nitroisatoic anhydride (1m7)

    PubMed Central

    Turner, Rushia; Shefer, Kinneret; Ares, Manuel

    2013-01-01

    Estimating the reactivity of 2′-hydroxyl groups along an RNA chain of interest aids in the modeling of the folded RNA structure; flexible loops tend to be reactive, whereas duplex regions are generally not. Among the most useful reagents for probing 2′-hydroxyl reactivity is 1-methyl-7-nitroisatoic anhydride (1m7), but the absence of a reliable, inexpensive source has prevented widespread adoption. An existing protocol for the conversion of an inexpensive precursor 4-nitroisatoic anhydride (4NIA) recommends the use of NaH in dimethylformamide (DMF), a reagent combination that most molecular biology labs are not equipped to handle, and that does not scale safely in any case. Here we describe a safer, one-pot method for bulk conversion of 4NIA to 1m7 that reduces costs and bypasses the use of NaH. We show that 1m7 produced by this method is free of side products and can be used to probe RNA structure in vitro. PMID:24141619

  18. Microwave Enabled One-Pot, One-Step Fabrication and Nitrogen Doping of Holey Graphene Oxide for Catalytic Applications.

    PubMed

    Patel, Mehulkumar; Feng, Wenchun; Savaram, Keerthi; Khoshi, M Reza; Huang, Ruiming; Sun, Jing; Rabie, Emann; Flach, Carol; Mendelsohn, Richard; Garfunkel, Eric; He, Huixin

    2015-07-15

    The unique properties of a holey graphene sheet, referred to as a graphene sheet with nanoholes in its basal plane, lead to wide range of applications that cannot be achieved by its nonporous counterpart. However, the large-scale solution-based production requires graphene oxide (GO) or reduced GO (rGO) as the starting materials, which take hours to days for fabrication. Here, an unexpected discovery that GO with or without holes can be controllably, directly, and rapidly (tens of seconds) fabricated from graphite powder via a one-step-one-pot microwave assisted reaction with a production yield of 120 wt% of graphite is reported. Furthermore, a fast and low temperature approach is developed for simultaneous nitrogen (N) doping and reduction of GO sheets. The N-doped holey rGO sheets demonstrate remarkable electrocatalytic capabilities for the electrochemical oxygen reduction reaction. The existence of the nanoholes provides a "short cut" for efficient mass transport and dramatically increases edges and surface area, therefore, creates more catalytic centers. The capability of rapid fabrication and N-doping as well as reduction of holey GO can lead to development of an efficient catalyst that can replace previous coin metals for energy generation and storage, such as fuel cells and metal-air batteries. PMID:25683019

  19. One-pot, water-based and high-yield synthesis of tetrahedral palladium nanocrystal decorated graphene.

    PubMed

    Fu, Gengtao; Tao, Lin; Zhang, Min; Chen, Yu; Tang, Yawen; Lin, Jun; Lu, Tianhong

    2013-09-01

    This paper reports a facile, water-based and one-pot synthesis of tetrahedral Pd nanocrystals (Pd-TNPs) with high yield and good size monodispersity supported on reduced graphene oxide (RGO) nanosheets via a co-chemical reduction method. The key synthetic strategy employed a positively charged polyallylamine-Pd(II) complex (PAH-Pd(II)) with un-coordinated amine groups as a linker molecule to immobilize Pd(II) species on the negatively charged graphene oxide (GO) surface through electrostatic interaction. As characterized by transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) techniques, well-defined Pd-TNPs with an average size of 9 nm were uniformly distributed on the RGO surface. The as-prepared Pd-TNPs/RGO nanohybrid with excellent colloidal stability in aqueous solution exhibits superior catalytic activity towards the degradation of methylene blue (MB) compared to both unsupported Pd-TNPs and Pd black. Thus, the resultant Pd-TNPs/RGO nanohybrid, as a promising heterogeneous catalyst, might have wide potential applications in water-based catalysis systems for the future. PMID:23864026

  20. Low cost, surfactant-less, one pot synthesis of Cu{sub 2}O nano-octahedra at room temperature

    SciTech Connect

    Ahmed, Asar; Gajbhiye, Namdeo S.; Joshi, Amish G.

    2011-08-15

    Cu{sub 2}O octahedra were successfully synthesized via a novel wet-chemical method using D-glucose and hydrazine as reducing agent at room temperature without the presence of any other surfactant. Presence of D-glucose was important for the stabilization of the evolved copper octahedra and also for facilitating the reduction of the Cu(II) ions. The existence of glucose moieties on the surface as capping agent was confirmed by the FT-IR spectra while there was presence of excess oxygen atoms on the surface leading to the formation of a thin CuO layer at the octahedra surface, as confirmed by the XPS study, probably promoted by the capping glucose. Effect of NaOH concentration on the reaction and the formation of octahedra was also studied. The formation mechanism of obtained Cu{sub 2}O octahedra has been discussed. These octahedra were then studied for their photocatalytic properties in degradation of organic dyes, rhodamine B and methyl orange. - Graphical abstract: Cu{sub 2}O octahedra were found to have thin layer of CuO, due to oxidation of surface Cu{sup +} atoms by the surfactant O atoms. Highlights: > Simple and inexpensive one pot synthesis of various Cu{sub 2}O nanostructures. > Surface properties studied by XPS. > Used as photocatalysis for degradation of rhodamine B.

  1. One-pot synthesis and sigma receptor binding studies of novel spirocyclic-2,6-diketopiperazine derivatives.

    PubMed

    Ghandi, Mehdi; Sherafat, Fatemeh; Sadeghzadeh, Masoud; Alirezapour, Behrouz

    2016-06-01

    New spirocyclic-2,6-diketopiperazine derivatives containing benzylpiperidine and cycloalkane moieties were synthesized by a one-pot two-step sequential Ugi/intramolecular N-amidation process in moderate to good yields. The in vitro ligand-binding profile studies performed on the sigma-1 and sigma-2 receptors revealed that the σ1 affinities and subtype selectivities of three spirocyclic piperidine derivatives are generally comparable to those of spirocycloalkane analogues. Compared to the low σ1 affinities obtained for cycloalkyl-substituted spirocyclic-2,6-diketopiperazines with n=2, those with n=1 proved to have optimal fitting with σ2 subtype by exhibiting higher affinities. Moreover, the best binding affinity and subtype selectivity was identified for compound 3c with Kiσ1=5.9±0.5nM and Kiσ2=563±21nM as well as 95-fold σ1/σ2 selectivity ratio, respectively. PMID:27090556

  2. A One Pot Synthesis of Novel Bioactive Tri-Substitute-Condensed-Imidazopyridines that Targets Snake Venom Phospholipase A2

    PubMed Central

    Anilkumar, Nirvanappa C.; Sundaram, Mahalingam S.; Mohan, Chakrabhavi Dhananjaya; Rangappa, Shobith; Bulusu, Krishna C.; Fuchs, Julian E.; Girish, Kesturu S.; Bender, Andreas; Basappa; Rangappa, Kanchugarakoppal S.

    2015-01-01

    Drugs such as necopidem, saripidem, alpidem, zolpidem, and olprinone contain nitrogen-containing bicyclic, condensed-imidazo[1,2-α]pyridines as bioactive scaffolds. In this work, we report a high-yield one pot synthesis of 1-(2-methyl-8-aryl-substitued-imidazo[1,2-α]pyridin-3-yl)ethan-1-onefor the first-time. Subsequently, we performed in silico mode-of-action analysis and predicted that the synthesized imidazopyridines targets Phospholipase A2 (PLA2). In vitro analysis confirmed the predicted target PLA2 for the novel imidazopyridine derivative1-(2-Methyl-8-naphthalen-1-yl-imidazo [1,2-α]pyridine-3-yl)-ethanone (compound 3f) showing significant inhibitory activity towards snake venom PLA2 with an IC50 value of 14.3 μM. Evidently, the molecular docking analysis suggested that imidazopyridine compound was able to bind to the active site of the PLA2 with strong affinity, whose affinity values are comparable to nimesulide. Furthermore, we estimated the potential for oral bioavailability by Lipinski's Rule of Five. Hence, it is concluded that the compound 3f could be a lead molecule against snake venom PLA2. PMID:26196520

  3. One-pot facile synthesis of branched Ag-ZnO heterojunction nanostructure as highly efficient photocatalytic catalyst

    NASA Astrophysics Data System (ADS)

    Huang, Qingli; Zhang, Qitao; Yuan, Saisai; Zhang, Yongcai; Zhang, Ming

    2015-10-01

    In this paper, the branched Ag-ZnO heterojunction nanostructure and the branched ZnO were synthesized successfully by a facile, green and one-pot hydrothermal method. Such branched heterojunction and the comparing branched pure ZnO were characterized by X-ray diffraction, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and UV-vis diffuse reflectance spectra (DRS). The photocatalytic degradation of RhB aqueous solution and acetaldehyde (CH3CHO) gas results both showed that the branched Ag-ZnO heterojunction possessed the enhanced photocatalytic properties in comparison to the branched ZnO and Ag-ZnO counterparts due to its special interface structures and fast separation of its photogenerated charge carriers. This method is simple, feasible and can provide an important clue for synthesis and application of other branched metal/semiconductor heterojunction nanostructures.

  4. One pot synthesis of biologically active pregnane derivatives, their single crystal structures, spectroscopic characterization and theoretical calculations

    NASA Astrophysics Data System (ADS)

    Sethi, Arun; Bhatia, Akriti; Bhatia, Gitika; Shrivastava, Atul; Prakash, Rohit

    2013-11-01

    One pot allylic oxidation of 3β-acetoxypregna-5,16-diene-20-one (2) and nucleophilic addition at C-16 position of 3β-hydroxypregna-5,16-diene-20-one (3) yielded 3β-acetoxypregna-5,16-diene-7,20-dione (4) and 3β-hydroxy-16α-(5'-hydroxypentyloxy)-pregn-5-ene-20-one (5) respectively in high yield. A detailed theoretical study supported by X-ray analysis of compounds 4 and 5 has been carried out. Conformational analysis of compounds 4 and 5 was done with the help of crystal structure, which crystallize out in orthorhombic form having P212121 space group. Structural characterization of compounds 4 and 5 was done with the aid of 1H, 13C NMR, IR, UV, ESI-MS and ESI-HRMS. The molecular geometries and vibrational frequencies for compounds 4 and 5 in the ground state were calculated using the Density functional theory (DFT) with 6-31G(d,p) basis set and compared with experimental data. 1H and 13C nuclear magnetic resonance magnetic shifts of 4 and 5 were calculated using GIAO method and compared with the experimental data. UV-Vis spectra of both the compounds were recorded and electronic properties such as HOMO-LUMO energies were calculated by time dependent TD-DFT approach. The compounds were screened for their anti-hyperlipidemic and anti-oxidant activity.

  5. One-pot DNA construction for synthetic biology: the Modular Overlap-Directed Assembly with Linkers (MODAL) strategy.

    PubMed

    Casini, Arturo; MacDonald, James T; De Jonghe, Joachim; Christodoulou, Georgia; Freemont, Paul S; Baldwin, Geoff S; Ellis, Tom

    2014-01-01

    Overlap-directed DNA assembly methods allow multiple DNA parts to be assembled together in one reaction. These methods, which rely on sequence homology between the ends of DNA parts, have become widely adopted in synthetic biology, despite being incompatible with a key principle of engineering: modularity. To answer this, we present MODAL: a Modular Overlap-Directed Assembly with Linkers strategy that brings modularity to overlap-directed methods, allowing assembly of an initial set of DNA parts into a variety of arrangements in one-pot reactions. MODAL is accompanied by a custom software tool that designs overlap linkers to guide assembly, allowing parts to be assembled in any specified order and orientation. The in silico design of synthetic orthogonal overlapping junctions allows for much greater efficiency in DNA assembly for a variety of different methods compared with using non-designed sequence. In tests with three different assembly technologies, the MODAL strategy gives assembly of both yeast and bacterial plasmids, composed of up to five DNA parts in the kilobase range with efficiencies of between 75 and 100%. It also seamlessly allows mutagenesis to be performed on any specified DNA parts during the process, allowing the one-step creation of construct libraries valuable for synthetic biology applications. PMID:24153110

  6. One-Pot Trimetallic Relay Catalysis: A Unified Approach for the Synthesis of β-Carbolines and Other [c]-Fused Pyridines.

    PubMed

    Dhiman, Seema; Mishra, Uttam K; Ramasastry, S S V

    2016-06-27

    A divergent strategy is presented for the synthesis of 1,3-di- and 1,3,4-trisubstituted β-carbolines through an unprecedented one-pot triple-orthogonal-metal relay catalysis, and 1,3-disubstituted 4-hydroxy-β-carbolines through a one-pot bimetallic relay catalysis from readily accessible 3-(2-aminophenyl)-5-hexenyn-3-ols. These strategies were elaborated to enable the synthesis of benzofuro[2,3-c]pyridines, benzothieno[2,3-c]pyridines, and isoquinolines, which otherwise require multistep synthesis. PMID:26953717

  7. Facile synthesis of brush poly(phosphoamidate)s via one-pot tandem ring-opening metathesis polymerization and atom transfer radical polymerization.

    PubMed

    Ding, Liang; Qiu, Jun; Wei, Jun; Zhu, Zhenshu

    2014-09-01

    Poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA)-based brush poly(phosphoamidate)s are successfully synthesized by a combination of ring-opening metathesis polymerization (ROMP) and atom transfer radical polymerization (ATRP) following either a commutative two-step procedure or a straightforward one-pot process using Grubbs ruthenium-based catalysts for tandem catalysis. Compared with the traditional polymerization method, combining ROMP and ATRP in a one-pot process allows the preparation of brush copolymers characterized by a relatively moderate molecular weight distribution and quantitative conversion of monomer. Moreover, the surface morphologies and aggregation behaviors of these polymers are studied by AFM and TEM measurements. PMID:24729161

  8. One-pot synthesis of tetrazole-1,2,5,6-tetrahydronicotinonitriles and cholinesterase inhibition: Probing the plausible reaction mechanism via computational studies.

    PubMed

    Hameed, Abdul; Zehra, Syeda Tazeen; Abbas, Saba; Nisa, Riffat Un; Mahmood, Tariq; Ayub, Khurshid; Al-Rashida, Mariya; Bajorath, Jürgen; Khan, Khalid Mohammed; Iqbal, Jamshed

    2016-04-01

    In the present study, one-pot synthesis of 1H-tetrazole linked 1,2,5,6-tetrahydronicotinonitriles under solvent-free conditions have been carried out in the presence of tetra-n-butyl ammonium fluoride trihydrated (TBAF) as catalyst and solvent. Computational studies have been conducted to elaborate two plausible mechanistic pathways of this one-pot reaction. Moreover, the synthesized compounds were screened for cholinesterases (acetylcholinesterase and butyrylcholinesterase) inhibition which are consider to be major malefactors of Alzheimer's disease (AD) to find lead compounds for further research in AD therapy. PMID:26851737

  9. PhI(OAc)2-mediated one-pot oxidative decarboxylation and aromatization of tetrahydro-β-carbolines: synthesis of norharmane, harmane, eudistomin U and eudistomin I.

    PubMed

    Kamal, Ahmed; Tangella, Yellaiah; Manasa, Kesari Lakshmi; Sathish, Manda; Srinivasulu, Vunnam; Chetna, Jadala; Alarifi, Abdullah

    2015-08-28

    Iodobenzene diacetate was employed as a mild and efficient reagent for one-pot oxidative decarboxylation of tetrahydro-β-carboline acids and dehydrogenation of tetrahydro-β-carbolines to access the corresponding aromatic β-carbolines. To the best of our knowledge this is the first synthesis of β-carbolines via a one-pot oxidative decarboxylation at ambient temperature. The utility of this protocol has been demonstrated in the synthesis of β-carboline alkaloids norharmane (2o), harmane (2p), eudistomin U (9) and eudistomin I (12). PMID:26099113

  10. A one-pot method for the selective conversion of hemicellulose from crop waste into C5 sugars and furfural by using solid acid catalysts.

    PubMed

    Sahu, Ramakanta; Dhepe, Paresh Laxmikant

    2012-04-01

    We present a solid-acid catalyzed one-pot method for the selective conversion of solid hemicellulose without its separation from other lignocellulosic components, such as cellulose and lignin. The reactions were carried out in aqueous and biphasic media to yield xylose, arabinose, and furfural. To overcome the drawbacks posed by mineral acid methods in converting hemicelllulose, we used heterogeneous catalysts that work at neutral pH. In a batch reactor, these heterogeneous catalysts, such as solid acids (zeolites, clays, metal oxides etc.), resulted in >90 % conversion of hemicellulose. It has been shown that the selectivity for the products can be tuned by changing the reaction conditions, for example, a reaction carried out in water at 170 °C for 1 h with HBeta (Si/Al=19) and HUSY (Si/Al=15) catalysts gave yields of 62 and 56 % for xylose and arabinose, respectively. With increased reaction time (6 h) and in presence of only water, HUSY resulted in yields of 30 % xylose + arabinose and 18 % furfural. However, in a biphasic reaction system (water + p-xylene, 170 °C, 6 h) yields of 56 % furfural with 17 % xylose+arabinose could be achieved. It was shown that with the addition of organic solvent the furfural yield could be increased from 18 to 56 %. Under optimized reaction conditions, >90 % carbon balance was observed. The study revealed that catalysts were recyclable with a 20 % drop in activity for each subsequent run. It was observed that temperature, pressure, reaction time, substrate to catalyst ratio, solvent, and so forth had an effect on product formation. The catalysts were characterized by means of X-ray diffraction, temperature-programmed desorption of NH(3), inductively coupled plasma spectroscopy, elemental analysis, and solid-state NMR ((29)Si, (27)Al) spectroscopy techniques. PMID:22411884

  11. Preparation of hybrid monolithic columns via "one-pot" photoinitiated thiol-acrylate polymerization for retention-independent performance in capillary liquid chromatography.

    PubMed

    Zhang, Haiyang; Ou, Junjie; Liu, Zhongshan; Wang, Hongwei; Wei, Yinmao; Zou, Hanfa

    2015-09-01

    A novel "one-pot" approach was developed for ultrarapid preparation of various hybrid monolithic columns in UV-transparent fused-silica capillaries via photoinitiated thiol-acrylate polymerization of an acrylopropyl polyhedral oligomertic silsesquioxane (acryl-POSS) and a monothiol monomer (1-octadecanethiol or sodium 3-mercapto-1-propanesulfonate) within 5 min, in which the acrylate not only homopolymerizes, but also couples with the thiol. This unique combination of two types of free-radical reaction mechanisms offers a simple way to fabricate various acrylate-based hybrid monoliths. The physical characterization, including scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and thermal gravimetric analysis was performed. The results indicated that the monothiol monomers were successfully incorporated into acryl-POSS-based hybrid monoliths. The column efficiencies for alkylbenzenes on the C18-functionalized hybrid monolithic column reached to 60 000-73 500 plates/m at the velocity of 0.33 mm/s in capillary liquid chromatography, which was far higher than that of previously reported POSS-based columns prepared via thermal-initiated free-radical polymerization without adding any thiol monomers. By plotting the plate height (H) of the alkylbenzenes versus the linear velocity (u) of the mobile phase, the results revealed a retention-independent efficient performance of small molecules in the isocratic elution. These results indicated that more homogeneous hybrid monoliths formed via photoinitiated thiol-acrylate polymerization; particularly, the use of the multifunctional cross-linker possibly prevented the generation of gel-like micropores, reducing mass transfer resistance (C-term). Another sulfonate-containing hybrid monolithic column also exhibited hydrophobicity and ion-exchange mechanism, and the dynamic binding capacity was calculated as 71.1 ng/cm (75 μm i.d.). PMID:26223285

  12. One-pot system for synthesis, assembly, and display of functional single-span membrane proteins on oil–water interfaces

    PubMed Central

    Yunker, Peter J.; Asahara, Haruichi; Hung, Kuo-Chan; Landry, Corey; Arriaga, Laura R.; Akartuna, Ilke; Heyman, John; Chong, Shaorong; Weitz, David A.

    2016-01-01

    Single-span membrane proteins (ssMPs) represent approximately one-half of all membrane proteins and play important roles in cellular communications. However, like all membrane proteins, ssMPs are prone to misfolding and aggregation because of the hydrophobicity of transmembrane helices, making them difficult to study using common aqueous solution-based approaches. Detergents and membrane mimetics can solubilize membrane proteins but do not always result in proper folding and functionality. Here, we use cell-free protein synthesis in the presence of oil drops to create a one-pot system for the synthesis, assembly, and display of functional ssMPs. Our studies suggest that oil drops prevent aggregation of some in vitro-synthesized ssMPs by allowing these ssMPs to localize on oil surfaces. We speculate that oil drops may provide a hydrophobic interior for cotranslational insertion of the transmembrane helices and a fluidic surface for proper assembly and display of the ectodomains. These functionalized oil drop surfaces could mimic cell surfaces and allow ssMPs to interact with cell surface receptors under an environment closest to cell–cell communication. Using this approach, we showed that apoptosis-inducing human transmembrane proteins, FasL and TRAIL, synthesized and displayed on oil drops induce apoptosis of cultured tumor cells. In addition, we take advantage of hydrophobic interactions of transmembrane helices to manipulate the assembly of ssMPs and create artificial clusters on oil drop surfaces. Thus, by coupling protein synthesis with self-assembly at the water–oil interface, we create a platform that can use recombinant ssMPs to communicate with cells. PMID:26721399

  13. One-pot system for synthesis, assembly, and display of functional single-span membrane proteins on oil-water interfaces.

    PubMed

    Yunker, Peter J; Asahara, Haruichi; Hung, Kuo-Chan; Landry, Corey; Arriaga, Laura R; Akartuna, Ilke; Heyman, John; Chong, Shaorong; Weitz, David A

    2016-01-19

    Single-span membrane proteins (ssMPs) represent approximately one-half of all membrane proteins and play important roles in cellular communications. However, like all membrane proteins, ssMPs are prone to misfolding and aggregation because of the hydrophobicity of transmembrane helices, making them difficult to study using common aqueous solution-based approaches. Detergents and membrane mimetics can solubilize membrane proteins but do not always result in proper folding and functionality. Here, we use cell-free protein synthesis in the presence of oil drops to create a one-pot system for the synthesis, assembly, and display of functional ssMPs. Our studies suggest that oil drops prevent aggregation of some in vitro-synthesized ssMPs by allowing these ssMPs to localize on oil surfaces. We speculate that oil drops may provide a hydrophobic interior for cotranslational insertion of the transmembrane helices and a fluidic surface for proper assembly and display of the ectodomains. These functionalized oil drop surfaces could mimic cell surfaces and allow ssMPs to interact with cell surface receptors under an environment closest to cell-cell communication. Using this approach, we showed that apoptosis-inducing human transmembrane proteins, FasL and TRAIL, synthesized and displayed on oil drops induce apoptosis of cultured tumor cells. In addition, we take advantage of hydrophobic interactions of transmembrane helices to manipulate the assembly of ssMPs and create artificial clusters on oil drop surfaces. Thus, by coupling protein synthesis with self-assembly at the water-oil interface, we create a platform that can use recombinant ssMPs to communicate with cells. PMID:26721399

  14. One-pot one-cluster synthesis of fluorescent and bio-compatible Ag14 nanoclusters for cancer cell imaging

    NASA Astrophysics Data System (ADS)

    Yang, Jie; Xia, Nan; Wang, Xinan; Liu, Xianhu; Xu, An; Wu, Zhikun; Luo, Zhixun

    2015-11-01

    Small-molecule-protected silver nanoclusters have smaller hydrodynamic diameter, and thus may hold greater potential in biomedicine application compared with the same core-sized, macromolecule (i.e. DNA)-protected silver nanoclusters. However, the live cell imaging labeled by small-molecule-protected silver nanoclusters has not been reported until now, and the synthesis and atom-precise characterization of silver nanoclusters have been challenging for a long time. We develop a one-pot one-cluster synthesis method to prepare silver nanoclusters capped with GSH which is bio-compatible. The as-prepared silver nanoclusters are identified to be Ag14(SG)11 (abbreviated as Ag14, SG: glutathione) by isotope-resolvable ESI-MS. The structure is probed by 1D NMR spectroscopy together with 2D COSY and HSQC. This cluster species is fluorescent and the fluorescence quantum yield is solvent-dependent. Very importantly, Ag14 was successfully applied to label lung cancer cells (A549) for imaging, and this work represents the first attempt to image live cells with small-molecule-protected silver nanoclusters. Furthermore, it is revealed that the Ag14 nanoclusters exhibit lower cytotoxicity compared with some other silver species (including silver salt, silver complex and large silver nanoparticles), and the explanation is also provided. The comparison of silver nanoclusters to state-of-the-art labeling materials in terms of cytotoxicity and photobleaching lifetime is also conducted.Small-molecule-protected silver nanoclusters have smaller hydrodynamic diameter, and thus may hold greater potential in biomedicine application compared with the same core-sized, macromolecule (i.e. DNA)-protected silver nanoclusters. However, the live cell imaging labeled by small-molecule-protected silver nanoclusters has not been reported until now, and the synthesis and atom-precise characterization of silver nanoclusters have been challenging for a long time. We develop a one-pot one

  15. Facile one-pot preparation and functionalization of luminescent chitosan-poly(methacrylic acid) microspheres based on polymer monomer pairs

    NASA Astrophysics Data System (ADS)

    Guo, Jia; Wang, Changchun; Mao, Weiyong; Yang, Wuli; Liu, Changjia; Chen, Jiyao

    2008-08-01

    In this paper, we present a facile and robust approach to synthesize multifunctional organic/inorganic composite microspheres with chitosan-poly(methacrylic acid) (CS-PMAA) shells and cadmium tellurium/iron oxide nanoparticle cores. Due to the strong electrostatic interaction between the negatively charged nanoparticles and the protonated CS polymers, the CS/nanoparticle complexes were utilized as templates for the subsequent polymerization of methacrylic acid. The resulting composite microspheres with luminescence and magnetic properties have regular morphologies and narrow size distributions. In contrast to previous reports, this route was based on a one-pot strategy without the aid of surfactants, organic solvent, or polymerizable ligands in aqueous solution. The encapsulated CdTe semiconductor nanocrystals inside the microspheres exhibited strong and stable photoluminescence properties in the pH range 5.0-11.0. When the pH was adjusted below 4, the photoluminescence decreased sharply and even quenched completely. However, the weakened fluorescence emission could be recovered to some degree upon an increase of pH above 5. Additionally, when both Fe3O4 and CdTe nanoparticles were encapsulated within CS-PMAA microspheres, the magnetic content of the microspheres could be efficiently controlled by tuning the feeding molar ratio of MAA monomers and glucosamine units of CS. From the preliminary attempts, it was found that the multifunctional microspheres as imaging agents could improve the rate and extent of cellular uptake under short-term exposure to an applied magnetic field, and so exhibit a great potential as bioactive molecule carriers.

  16. One-pot room temperature synthesizing Cu- and Mn-doped ZnSe nanocrystals by a rapid photochemical method

    NASA Astrophysics Data System (ADS)

    Bahador, A. R.; Molaei, M.; Karimipour, M.

    2016-04-01

    In this work, a one-pot, rapid, green and room temperature photochemical synthesis of transition metal (TM; Cu, Mn)-doped ZnSe nanocrystals (NCs) was reported. NCs were successfully characterized using Fourier transform-infrared (FT-IR), photoluminescence (PL) and UV-Visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), X-ray diffractometry (XRD) and energy dispersive X-ray spectra (EDX). FT-IR spectra confirmed the capping of ZnSe by thioglycolic acid (TGA) molecules. XRD and TEM analysis demonstrated zinc blend phase NCs with an average size of around 3 nm. Band gap of ZnSe NCs was about 3.6 eV which it was decreased by increasing the illumination time. PL spectra of ZnSe NCs showed a broad emission with two peaks located at 380 nm and 490 nm related to excitonic and trap states emission, respectively. For ZnSe:Cu NCs, excitonic emission disappeared completely and PL intensity of trap states emission increased with the increase in the Cu2+ ion concentration so that for precursor ratio of Cu:Zn 1%, optimal value of PL intensity was obtained. For ZnSe:Mn NCs, the excitonic emission decreased gradually with the increase in the impurity concentration whereas trap state emission increased. Moreover, a peak about 590 nm was appeared from 4T1-6A1 transition of the Mn2+ impurity, demonstrating the Mn incorporation inside the ZnSe NCs structure.

  17. A Practical One-Pot Synthesis of Positron Emission Tomography (PET) Tracers via Nickel-Mediated Radiofluorination

    PubMed Central

    Zlatopolskiy, Boris D; Zischler, Johannes; Urusova, Elizaveta A; Endepols, Heike; Kordys, Elena; Frauendorf, Holm; Mottaghy, Felix M; Neumaier, Bernd

    2015-01-01

    Recently a novel method for the preparation of 18F-labeled arenes via oxidative [18F]fluorination of easily accessible and sufficiently stable nickel complexes with [18F]fluoride under exceptionally mild reaction conditions was published. The suitability of this procedure for the routine preparation of clinically relevant positron emission tomography (PET) tracers, 6-[18F]fluorodopamine (6-[18F]FDA), 6-[18F]fluoro-l-DOPA (6-[18F]FDOPA) and 6-[18F]fluoro-m-tyrosine (6-[18F]FMT), was evaluated. The originally published base-free method was inoperative. However, a “low base” protocol afforded protected radiolabeled intermediates in radiochemical conversions (RCCs) of 5–18 %. The subsequent deprotection step proceeded almost quantitatively (>95 %). The simple one-pot two-step procedure allowed the preparation of clinical doses of 6-[18F]FDA and 6-[18F]FDOPA within 50 min (12 and 7 % radiochemical yield, respectively). In an unilateral rat model of Parkinsons disease, 6-[18F]FDOPA with high specific activity (175 GBq μmol−1) prepared using the described nickel-mediated radiofluorination was compared to 6-[18F]FDOPA with low specific activity (30 MBq μmol−1) produced via conventional electrophilic radiofluorination. Unexpectedly both tracer variants displayed very similar in vivo properties with respect to signal-to-noise ratio and brain distribution, and consequently, the quality of the obtained PET images was almost identical. PMID:26478840

  18. One-pot solvothermal synthesis of dual-phase titanate/titania Nanoparticles and their adsorption and photocatalytic Performances

    SciTech Connect

    Cheng, Yu Hua; Gong, Dangguo; Tang, Yuxin; Ho, Jeffery Weng Chye; Tay, Yee Yan; Lau, Wei Siew; Wijaya, Olivia; Lim, Jiexiang; Chen, Zhong

    2014-06-01

    Dual phase titanate/titania nanoparticles undergo phase transformation gradually with the increase of solvothermal synthesis temperature from 100 °C to 200 °C, and eventually are fully transformed into anatase TiO{sub 2}. The crystal structure change results in the changes of optical absorption, sensitizer/dopant formation and surface area of the materials which finally affect the overall dye removal ability. Reactions under dark and light have been conducted to distinguish the contributions of surface adsorption from photocatalytic degradation. The sample synthesized at 160 °C (S160) shows the best performances for both adsorption under dark and photocatalytic degradation of methylene blue (MB) under visible light irradiation. The adsorption mechanism for S160 is determined as monolayer adsorption based on the adsorption isotherm test under dark condition, and an impressive adsorption capacity of 162.19 mg/g is achieved. For the photocatalytic application, this sample at 0.1 g/L loading is also able to degrade 20 ppm MB within 6 hours under the visible light (>420 nm) condition. - Graphical abstract: The effect of solvothermal synthesis temperature on the formation and dye removal performance of dual phase titanate/titania nanoparticles was unveiled and optimized. - Highlights: • Low temperature one-pot solvothermal synthesis of dual-phase photocatalysts. • Correlation of the synthesis temperature is made with the phase composition. • Adsorption isotherm, kinetics, photocatalytic degradation were studied. • Synthesis at 160 °C yields the best material for adsorption of MB in dark. • The same sample also shows the best visible light degradation of MB.

  19. One-pot synthesis of pH-responsive hybrid nanogel particles for the intracellular delivery of small interfering RNA.

    PubMed

    Khaled, Sm Z; Cevenini, Armando; Yazdi, Iman K; Parodi, Alessandro; Evangelopoulos, Michael; Corbo, Claudia; Scaria, Shilpa; Hu, Ye; Haddix, Seth G; Corradetti, Bruna; Salvatore, Francesco; Tasciotti, Ennio

    2016-05-01

    This report describes a novel, one-pot synthesis of hybrid nanoparticles formed by a nanostructured inorganic silica core and an organic pH-responsive hydrogel shell. This easy-to-perform, oil-in-water emulsion process synthesizes fluorescently-doped silica nanoparticles wrapped within a tunable coating of cationic poly(2-diethylaminoethyl methacrylate) hydrogel in one step. Transmission electron microscopy and dynamic light scattering analysis demonstrated that the hydrogel-coated nanoparticles are uniformly dispersed in the aqueous phase. The formation of covalent chemical bonds between the silica and the polymer increases the stability of the organic phase around the inorganic core as demonstrated by thermogravimetric analysis. The cationic nature of the hydrogel is responsible for the pH buffering properties of the nanostructured system and was evaluated by titration experiments. Zeta-potential analysis demonstrated that the charge of the system was reversed when transitioned from acidic to basic pH and vice versa. Consequently, small interfering RNA (siRNA) can be loaded and released in an acidic pH environment thereby enabling the hybrid particles and their payload to avoid endosomal sequestration and enzymatic degradation. These nanoparticles, loaded with specific siRNA molecules directed towards the transcript of the membrane receptor CXCR4, significantly decreased the expression of this protein in a human breast cancer cell line (i.e., MDA-MB-231). Moreover, intravenous administration of siRNA-loaded nanoparticles demonstrated a preferential accumulation at the tumor site that resulted in a reduction of CXCR4 expression. PMID:26901429

  20. Synthesis of β-arylated alkylamides via Pd-catalyzed one-pot installation of a directing group and C(sp3)–H arylation

    PubMed Central

    Zhang, Yi; Cao, Xiaoji; Wan, Jie-Ping

    2016-01-01

    Summary The synthesis of β-arylated alkylamides via alkyl C–H bond arylation has been realized by means of direct one-pot reactions of acyl chlorides, aryl iodides and 8-aminoquinoline. Depending on the structure of the starting materials, both single and double β-arylated alkylamides could be accessed. PMID:27340500

  1. One-pot synthesis of simple alkaloids: 2,3-polymethylene-4(3H)-quinazolinones, luotonin A, tryptanthrin, and rutaecarpine.

    PubMed

    Jahng, Katherine Chae; Kim, Seung Ill; Kim, Dong Hyeon; Seo, Chang Seob; Son, Jong-Keun; Lee, Seung Ho; Lee, Eung Seok; Jahng, Yurngdong

    2008-04-01

    One-pot synthesis of various 2,3-polymethylene-4(3H)-quinazolinones from anthranilic acid, corresponding lactam and SOCl(2) is described, which can be applicable to the synthesis of simple 4(3H)-quinazolinone-derived alkaloids, such as luotonin A, tryptanthrin, and rutaecarpine. PMID:18379119

  2. Formal [4+2] annulation of enaminones and cyanomethyl sulfur ylide: one-pot access to polysubstituted pyridin-2(1H)-ones.

    PubMed

    Zhang, Qian; Liu, Xu; Xin, Xiaoqing; Zhang, Rui; Liang, Yongjiu; Dong, Dewen

    2014-12-18

    A facile and efficient one-pot synthesis of polysubstituted pyridin-2(1H)-ones from readily available enaminones and the cyanomethyl sulfonium bromide salt in the presence of cesium carbonate is developed, and a mechanism involving sequential nucleophilic vinylic substitution (S(N)V), intramolecular nucleophilic cyclization and dealkylation reactions is proposed. PMID:25349951

  3. Triflic acid controlled successive annelation of aromatic sulfonamides: An efficient one-pot synthesis of N-sulfonyl pyrroles, indoles and carbazoles

    PubMed Central

    Abid, Mohammed; Teixeira, Liliana; Török, Béla

    2009-01-01

    A novel one-pot synthesis of N-substituted heterocycles via successive cyclization/annelation starting from primary sulfonamides is described. This process leads directly to N-sulfonyl pyrroles, indoles and carbazoles. The selection of appropriate reactant/triflic acid ratio successfully controls the formation of the desired product. PMID:19629194

  4. One-pot nitro-Mannich/hydroamination cascades for the direct synthesis of 2,5-disubstituted pyrroles using base and gold catalysis.

    PubMed

    Barber, David M; Sanganee, Hitesh; Dixon, Darren J

    2011-04-21

    An efficient, easy to perform, one-pot reaction cascade for the synthesis of 2,5-disubstituted pyrroles from p-toluenesulfonyl protected imines and 4-nitrobut-1-yne under a combination of base and gold(III) catalysis is reported. PMID:21399786

  5. A Robust, "One-Pot" Method for Acquiring Kinetic Data for Hammett Plots Used to Demonstrate Transmission of Substituent Effects in Reactions of Aromatic Ethyl Esters

    ERIC Educational Resources Information Center

    Yau, Hon Man; Haines, Ronald S.; Harper, Jason B.

    2015-01-01

    A "one-pot" method for acquiring kinetic data for the reactions of a series of substituted aromatic esters with potassium hydroxide using [supserscript 13]C NMR spectroscopy is described, which provides an efficient way to obtain sufficient data to demonstrate the Hammett equation in undergraduate laboratories. The method is…

  6. PPh3O as an Activating Reagent for One-Pot Stereoselective Syntheses of Di- and Polybrominated Esters from Simple Aldehydes.

    PubMed

    Yu, Tian-Yang; Wei, Hao; Luo, Yong-Chun; Wang, Yao; Wang, Zhu-Yin; Xu, Peng-Fei

    2016-04-01

    An efficient one-pot method for the syntheses of di- and polybrominated esters from readily available aldehydes is reported. The direct use of the in situ generated byproduct PPh3O in the following reactions greatly improves the efficiency of the cascade. Also, the substrate scope of the reaction is proved to be broad. PMID:26975436

  7. A one-pot synthesis of 1,6,9,13-tetraoxadispiro(4.2.4.2)tetradecane by hydrodeoxygenation of xylose using a palladium catalyst

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an effort to expand the number of biobased chemicals available from sugars, xylose has been converted to 1,6,9,13-tetraoxadispiro(4.2.4.2)tetradecane in a one-pot reaction using palladium supported on silica-alumina as the catalyst. The title compound is produced in 35-40% yield under 7 MPa H2 pr...

  8. One-Pot Synthesis of Benzo[4,5]imidazo[2,1-a]isoquinolines and Isoquinolino[3,4-b]quinoxalines via Tandem Cyclization Strategies.

    PubMed

    Bagdasarian, Alex L; Nguyen, Huy H; Palazzo, Teresa A; Fettinger, James C; Haddadin, Makhluf J; Kurth, Mark J

    2016-05-01

    Two operationally simple one-pot protocols have been developed for the synthesis of amino-functionalized benzo[4,5]imidazo[2,1-a]isoquinolines and isoquinolino[3,4-b]quinoxalines. Optimization data and substrate scope for these atom-economical transformations, which engage commercially available o-phenylenediamines and o-cyanobenzaldehydes, are discussed. PMID:27030441

  9. Greener and rapid access to bio-active heterocycles: one-pot solvent-free synthesis of 1,3,4-oxadiazoles and 1,3,4-thiadiazoles

    EPA Science Inventory

    A novel one-pot solvent free synthesis of 1,3,4-oxadiazoles and 1,3,4-thiadiazoles by condensation of acid hydrazide and triethyl orthoalkanates under microwave irradiations is reported. This green protocol was catalyzed efficiently by solid supported Nafion®NR50 and phosphorus p...

  10. Novel and efficient one-pot five- and six-component reactions for the stereoselective synthesis of highly functionalized enaminones and dithiocarbamates.

    PubMed

    Bararjanian, Morteza; Balalaie, Saeed; Rominger, Frank; Movassagh, Barahman; Bijanzadeh, Hamid Reza

    2011-05-01

    Efficient methods for stereoselective synthesis of polyfunctional (E)-enaminones and (Z)-dithiocarbamates via one-pot five- and six-component sequential Ugi/Nucleophilic addition reactions are described. High yields and high bond forming efficiency, and simple operations are the advantages of this method. PMID:21072590

  11. Synthesis of dibenzoxepine lactams via a Cu-catalyzed one-pot etherification/aldol condensation cascade reaction: application toward the total synthesis of aristoyagonine.

    PubMed

    Lim, Hye Sun; Choi, Young Lok; Heo, Jung-Nyoung

    2013-09-20

    A general synthesis of dibenzoxepine lactams has been developed using a one-pot Cu-catalyzed etherification/aldol condensation cascade reaction. The reaction of 4-hydroxyisoindolin-1-one with a wide range of 2-bromobenzaldehydes in the presence of a copper catalyst provided various aristoyagonine derivatives in good yields. PMID:24000941

  12. Consecutive condensation, C-N and N-N bond formations: a copper- catalyzed one-pot three-component synthesis of 2H-indazole.

    PubMed

    Kumar, Manian Rajesh; Park, Ahbyeol; Park, Namjin; Lee, Sunwoo

    2011-07-01

    2H-Indazoles are synthesized using copper-catalyzed, one-pot, three-component reactions of 2-bromobenzaldehydes, primary amines, and sodium azide. A copper catalyst plays the key role in the formation of C-N and N-N bonds. This method has a broad substrate scope with a high tolerance for a variety of functional groups. PMID:21644532

  13. TANDEM BIS-ALDOL REACTION OF KETONES: A FACILE ONE-POT SYNTHESIS OF 1,3-DIOXANES IN AQUEOUS MEDIUM

    EPA Science Inventory

    A novel tandem bis-aldol reaction of ketone with paraformaldehyde catalyzed by polystyrenesulfonic acid in aqueous medium delivers 1,3-dioxanes in high yield. This one pot, operationally simple microwave-assisted synthetic protocol proceeds efficiently in water in the absence of ...

  14. Microwave-assisted synthesis of dinucleoside analogues containing a thiazolidin-4-one linkage via one-pot tandem Staudinger/aza-Wittig/cyclization.

    PubMed

    Shen, Fengjuan; Li, Xiaoliu; Zhang, Xiaoyuan; Yin, Qingmei; Qin, Zhanbin; Chen, Hua; Zhang, Jinchao; Ma, Zhaipu

    2011-08-21

    Dinucleosides containing a thiazolidin-4-one linkage were prepared by one-pot tandem Staudinger/aza-Wittig/intermolecular cyclization under microwave irradiation and their structures were confirmed. Preliminary examination of HIV-RT inhibition showed that the dinucleosides containing (R)-thiazolidin-4-one linkage are significantly more active than those containing (S)-thiazolidin-4-one linkage. PMID:21717016

  15. Rapid access to novel 1,2,3-triazolo-heterocyclic scaffolds via tandem Knoevenagel condensation/azide-alkyne 1,3-dipolar cycloaddition reaction in one pot.

    PubMed

    Maurya, Ram Awatar; Adiyala, Praveen Reddy; Chandrasekhar, D; Reddy, Chada Narsimha; Kapure, Jeevak Sopanrao; Kamal, Ahmed

    2014-09-01

    An operationally simple, one-pot, two-step cascade method has been developed to afford biologically important fused 1,2,3-triazolo-heterocyclic scaffolds from 2-alkynyl aryl(heteroaryl) aldehydes and phenacyl azides. This unique atom economical transformation engages four reactive centers (aldehyde, alkyne, active methylene, and azide) under metal-free catalysis. PMID:24945583

  16. Initiator and Photocatalyst-Free Visible Light Induced One-Pot Reaction: Concurrent RAFT Polymerization and CuAAC Click Reaction.

    PubMed

    Wang, Jie; Wang, Xinbo; Xue, Wentao; Chen, Gaojian; Zhang, Weidong; Zhu, Xiulin

    2016-05-01

    A new, visible light-catalyzed, one-pot and one-step reaction is successfully employed to design well-controlled side-chain functionalized polymers, by the combination of ambient temperature revisible addtion-fragmentation chain transfer (RAFT) polymerization and click chemistry. Polymerizations are well controlled in a living way under the irradiation of visible light-emitting diode (LED) light without photocatalyst and initiator, using the trithiocarbonate agent as iniferter (initiator-transfer agent-terminator) agent at ambient temperature. Fourier transfer infrared spectroscopy (FT-IR), NMR, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) data confirm the successful one-pot reaction. Compared to the reported zero-valent metal-catalyzed one-pot reaction, the polymerization rate is much faster than that of the click reaction, and the visible light-catalyzed one-pot reaction can be freely and easily regulated by turning on and off the light. PMID:27029002

  17. In situ one-pot preparation of superparamagnetic hydrophilic porous microspheres for covalently immobilizing penicillin G acylase to synthesize amoxicillin

    NASA Astrophysics Data System (ADS)

    Xue, Ping; Gu, Yaohua; Su, Weiguang; Shuai, Huihui; Wang, Julan

    2016-01-01

    Magnetic hydrophilic porous microspheres were successfully one-pot synthesized for the first time via in situ inverse suspension polymerization of glycidyl methacrylate, N,N‧-methylene bisacrylamide and 2-hydroxyethyl methacrylate in the presence of Fe3+ and Fe2+ dispersed in formamide, which were denoted as magnetic Fe3O4-GMH microspheres. The morphology and properties of magnetic Fe3O4-GMH microspheres were characterized by SEM, VSM, XRD, FTIR, and so on. The formamide content had an important influence on the morphology of Fe3O4-GMH, and nearly perfectly spherical Fe3O4-GMH particles were formed when the amount of formamide was 15 ml. The diameters of the microspheres were in the range of 100-200 μm and Fe3O4-GMH exhibited superparamagnetic behavior with the saturation magnetization of 5.44 emu/g. The specific surface area of microspheres was 138.7 m2/g, the average pore diameter and pore volume were 15.1 nm and 0.60 cm3/g, respectively. The content of oxirane groups on Fe3O4-GMH was 0.40 mmol/g. After penicillin G acylase (PGA) was covalently immobilized on Fe3O4-GMH microspheres, the catalytic performance for amoxicillin synthesis by 6-aminopenicillanic acid and D-hydroxyphenylglycine methyl ester was largely improved. As a result, 90.1% amoxicillin yield and 1.18 of the synthesis/hydrolysis (S/H) ratio were achieved on PGA/Fe3O4-GMH with ethylene glycol as solvent, but only 62.6% amoxicillin yield and 0.37 of the S/H ratio were obtained on free PGA under the same reaction conditions. Furthermore, the amoxicillin yield and S/H ratio were still kept at 88.2% and 1.06, respectively after the immobilized PGA was magnetically separated and recycled for 10 times, indicating that PGA/Fe3O4-GMH had a very good reusability.

  18. One-Pot Synthesis and Evaluation of Antileishmanial Activities of Functionalized S-Alkyl/Aryl Benzothiazole-2-carbothioate Scaffold.

    PubMed

    Dar, Ajaz A; Shadab, M; Khan, Suman; Ali, Nahid; Khan, Abu T

    2016-04-15

    The synthesis of hitherto unreported S-alkyl/aryl benzothiazole-2-carbothioate is reported from thiols, oxalyl chloride, and 2-aminothiophenols using 10 mol % n-tetrabutylammonium iodide (TBAI) as catalyst in acetonitrile through multicomponent reaction (MCR) strategy. The present protocol favored formation of benzothiazoles and thioesters via simultaneous formation of C-N and C-S bonds in good yields with a wide range of substrates. A few of the synthesized derivatives were evaluated for their antimicrobial activity against the protozoan parasite Leishmania donovani, a causative agent of visceral leishmaniasis (VL). Further, these compounds displayed no toxicity toward macrophage RAW 264.7 cells and are therefore nontoxic and effective antileishmanial leads. In silico docking studies were performed to understand the possible binding site interaction with trypanothione reductase (TryR). PMID:26999637

  19. Multicomponent membranes

    DOEpatents

    Kulprathipanja, Santi; Kulkarni, Sudhir S.; Funk, Edward W.

    1988-01-01

    A multicomponent membrane which may be used for separating various components which are present in a fluid feed mixture comprises a mixture of a plasticizer such as a glycol and an organic polymer cast upon a porous organic polymer support. The membrane may be prepared by casting an emulsion or a solution of the plasticizer and polymer on the porous support, evaporating the solvent and recovering the membrane after curing.

  20. Manganese dioxide mediated one-pot synthesis of methyl 9H-pyrido[3,4-b]indole-1-carboxylate: Concise synthesis of alangiobussinine.

    PubMed

    Baiget, Jessica; Llona-Minguez, Sabin; Lang, Stuart; Mackay, Simon P; Suckling, Colin J; Sutcliffe, Oliver B

    2011-01-01

    The carboline ring system is an important pharmacophore found in a number of biologically important targets. Development of synthetic routes for the preparation of these compounds is important in order to prepare a range of analogues containing the carboline heterocyclic moiety. A manganese dioxide mediated one-pot method starting with an activated alcohol and consisting of alcohol oxidation, Pictet-Spengler cyclisation, and oxidative aromatisation, offers a convenient process that allows access to β-carbolines. This one-pot process for the preparation of methyl 9H-pyrido[3,4-b]indole-1-carboxylate has subsequently been used as the key step in the synthesis of alangiobussinine and a closely related analogue. PMID:22043251

  1. Excellent performance of one-pot synthesized Cu-SSZ-13 catalyst for the selective catalytic reduction of NOx with NH3.

    PubMed

    Xie, Lijuan; Liu, Fudong; Ren, Limin; Shi, Xiaoyan; Xiao, Feng-Shou; He, Hong

    2014-01-01

    Cu-SSZ-13 samples prepared by a novel one-pot synthesis method achieved excellent NH3-SCR performance and high N2 selectivity from 150 to 550 °C after ion exchange treatments. The selected Cu3.8-SSZ-13 catalyst was highly resistant to large space velocity (800 000 h(-1)) and also maintained high NOx conversion in the presence of CO2, H2O, and C3H6 in the simulated diesel exhaust. Isolated Cu(2+) ions located in three different sites were responsible for its excellent NH3-SCR activity. Primary results suggest that the one-pot synthesized Cu-SSZ-13 catalyst is a promising candidate as an NH3-SCR catalyst for the NOx abatement from diesel vehicles. PMID:24295053

  2. Manganese dioxide mediated one-pot synthesis of methyl 9H-pyrido[3,4-b]indole-1-carboxylate: Concise synthesis of alangiobussinine

    PubMed Central

    Baiget, Jessica; Llona-Minguez, Sabin; MacKay, Simon P; Suckling, Colin J; Sutcliffe, Oliver B

    2011-01-01

    Summary The carboline ring system is an important pharmacophore found in a number of biologically important targets. Development of synthetic routes for the preparation of these compounds is important in order to prepare a range of analogues containing the carboline heterocyclic moiety. A manganese dioxide mediated one-pot method starting with an activated alcohol and consisting of alcohol oxidation, Pictet–Spengler cyclisation, and oxidative aromatisation, offers a convenient process that allows access to β-carbolines. This one-pot process for the preparation of methyl 9H-pyrido[3,4-b]indole-1-carboxylate has subsequently been used as the key step in the synthesis of alangiobussinine and a closely related analogue. PMID:22043251

  3. Diverse Tp*-Capped W-Cu-S Clusters from One-Pot Assembly Involving in Situ Thiolation of Phosphines.

    PubMed

    Zhao, Xin; Zhou, Feng; Liu, Quan; Chen, Qiu-Fang; Yang, Jun-Yi; Zhang, Wen-Hua; Song, Ying-Lin; Lang, Jian-Ping

    2016-02-15

    In the absence/presence of S8, the one-pot assembly of [Et4N][Tp*WS3] [1; Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate] with [Cu(MeCN)4]PF6 and bis- or tetraphosphine ligands 1,2-bis(diphenylphosphino)ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp), 1,4-bis(diphenylphosphino)butane (dppb), and N,N,N',N'-tetrakis(diphenylphosphinomethyl)ethylenediamine (dppeda) produces six W-Cu-S clusters, namely, [(Tp*WS3Cu2Cl)2(dppe)] (2), [Tp*WS3Cu4(dppp)2(μ4-Cl)(μ-Cl)]PF6·MeCN (3·MeCN), [(Tp*WS3Cu3)2(μ4-Cl)(μ-Cl)2(dpppS2)] (4), [(Tp*WS3Cu2Cl)2(dppbS2)]·2MeCN·2H2O (5·2MeCN·2H2O), [(Tp*WS3Cu3Cl2)2(dppbS2)] (6), and [(Tp*WS3Cu3)2(Ph2PS2)3(μ6-Cl)0.5](PF6)0.5·0.75CH2Cl2 (7·0.75CH2Cl2). Compounds 2-7 are characterized by elemental analysis, IR, UV-vis, (1)H and (31)P{(1)H} NMR, electrospray ionization mass spectrometry, and X-ray crystallography. For 2, the dppe ligand bridges a pair of butterfly-shaped [Tp*WS3Cu2] cores to form a double-butterfly-shaped structure. For 4, the dppp ligand is susceptible toward S association and forms an in situ generated dpppS2 ligand, supporting an octanuclear double-half-open-cubane structure and contrasting an analogous system wherein a pentanuclear motorcycle-shaped cationic cluster 3 is formed with the absence of S8. A longer dppb ligand readily converts to S-based ligands in 5 and 6, subsequently serving as bridges between a pair of a butterfly-shaped (5) and nest-shaped (6) clusters. Further use of a tetraphosphine ligand, dppeda, in the cluster formation, with the presence of S8, leads to an unexpected ligand degradation to give the [Ph2PS2](-) anions. Three [Ph2PS2](-) anions juxtapose a pair of nest-shaped cluster cores to yield an octanuclear cluster, 7, featuring a cage to encapsulate μ6-Cl(-). The third-order nonlinear-optical (NLO) properties of 2-7 in N,N-dimethylformamide, investigated using a Z-scan technique at 532 nm, show that 2-6 have a reverse saturable absorption, while 7 has a notable saturable

  4. One-pot synthesis of 2-amino-4(3H)-quinazolinones via ring-opening of isatoic anhydride and palladium-catalyzed oxidative isocyanide-insertion.

    PubMed

    Ji, Fei; Lv, Mei-Fang; Yi, Wen-Bin; Cai, Chun

    2014-08-14

    An efficient and practical two-step process has been developed for the synthesis of 2-amino-4(3H)-quinazolinones via ring-opening of isatoic anhydride and palladium-catalyzed oxidative isocyanide-insertion in one pot. This regioselective procedure could construct a wide range of 2-amino-4(3H)-quinazolinones in moderate to excellent yields. Furthermore, the methodology also had distinct advantages of easily accessible starting materials and operational simplicity. PMID:24968809

  5. Synthesis of 5-Amino-2,5-dihydro-1H-benzo[b]azepines Using a One-Pot Multibond Forming Process.

    PubMed

    Sharif, Salaheddin A I; Calder, Ewen D D; Delolo, Fábio G; Sutherland, Andrew

    2016-08-01

    Rapid access to allylic trichloroacetimidates bearing a 2-allylaminoaryl group from readily available 2-iodoanilines combined with a one-pot multibond forming process has allowed the efficient synthesis of a series of 5-amino-2,5-dihydro-1H-benzo[b]azepines. The potential of these compounds as synthetic building blocks was demonstrated by the preparation of a late-stage intermediate of the hyponatremia agent, mozavaptan. PMID:27414232

  6. Direct, one-pot reductive alkylation of anilines with functionalized acetals mediated by triethylsilane and TFA. Straightforward route for unsymmetrically substituted ethylenediamine.

    PubMed

    Righi, Marika; Bedini, Annalida; Piersanti, Giovanni; Romagnoli, Federica; Spadoni, Gilberto

    2011-01-21

    A new, robust, and reliable method has been developed for the selective reductive N-alkylation of primary and secondary aromatic amines with some functionalized acetals using TFA/Et(3)SiH as a reagent combination. A variety of unsymmetrically substituted ethylenediamines can be synthesized in a one-pot procedure in excellent yields at room temperature. This new procedure offers significant advantages over previous synthetic approaches, including brevity, mild reaction conditions, excellent yields, and high functional group tolerance. PMID:21175194

  7. Gold or no gold: one-pot synthesis of tetrahydrobenz[b]azepin-4-ones from tertiary N-(but-3-ynyl)anilines.

    PubMed

    Cui, Li; Zhang, Guozhu; Peng, Yu; Zhang, Liming

    2009-03-19

    Depending on the tertiary aniline substrates, an efficient, one-pot synthesis of tetrahydrobenz[b]azepin-4-ones needs either gold catalysts or no catalyst at all. In the reaction, the aniline nitrogen plays a unique role in relaying "O" from m-CPBA to a tethered C-C triple bond, which is inert to the oxidant under the mild reaction conditions. PMID:19220014

  8. A one-pot copper catalyzed biomimetic route to N-heterocyclic amides from methyl ketones via oxidative C-C bond cleavage.

    PubMed

    Subramanian, Parthasarathi; Indu, Satrajit; Kaliappan, Krishna P

    2014-12-01

    A direct one-pot Cu-catalyzed biomimetic oxidation of methyl ketones to pharmaceutically important N-heterocyclic amides is reported. The scope of the method is broad, scalable, and mild, and the reaction is tolerant with various acid, base sensitive functionalities with multiple heteroatoms and aryl halides. The extensive mechanistic studies suggest that this reaction follows the Luciferin-Luciferase-like pathway. PMID:25409417

  9. One pot production of 5-hydroxymethylfurfural with high yield from cellulose by a Brønsted-Lewis-surfactant-combined heteropolyacid catalyst.

    PubMed

    Zhao, Shun; Cheng, Mingxing; Li, Junzi; Tian, Juan; Wang, Xiaohong

    2011-02-21

    A Brønsted-Lewis-surfactant-combined heteropolyacid (HPA) Cr[(DS)H(2)PW(12)O(40)](3) has been synthesized, and is used as a heterogeneous catalyst for the conversion of cellulose to 5-hydroxymethylfurfural in one pot within 2 h at 150 °C with 77.1% conversion and 52.7% yield. This micellar HPA catalyst shows stability and can be recycled by simple separation process. PMID:21203610

  10. One-pot sonochemical synthesis of 1,3-thiazolidin-4-ones using nano-CdZr4(PO4)6 as a robust heterogeneous catalyst.

    PubMed

    Safaei-Ghomi, Javad; Navvab, Maryam; Shahbazi-Alavi, Hossein

    2016-07-01

    An efficient three-component synthesis of 1,3-thiazolidin-4-ones is described by one-pot condensation of aldehydes, aniline and thioglycolic acid with nano-CdZr4(PO4)6 as a robust heterogeneous catalyst under ultrasonic irradiation. Use of simple and readily available starting materials, experimental simplicity, applying the sonochemical methodology as an efficient method and innocuous means of activation in synthetic chemistry are some advantages of this protocol. PMID:26964928

  11. One-pot assembly of metal/organic-acid sites on amine-functionalized ligands of MOFs for photocatalytic hydrogen peroxide splitting.

    PubMed

    Qin, Lei; Li, Zhaowen; Hu, Qiong; Xu, Zehai; Guo, Xinwen; Zhang, Guoliang

    2016-06-01

    A one-pot organic-acid-directed post-synthetic modification allows molecular iron/citric acid complexes to be anchored into amine-functionalized MOFs by a simple and rapid liquid spraying method. Amidation between organic acid and -NH2 groups of ligands can lead to more small nanoparticles (NPs) that are well-dispersed into MOFs and exhibit high activity for photocatalytic H2O2 splitting. PMID:27166081

  12. Protecting-group-free synthesis of taiwaniaquinone H using a one-pot thermal ring expansion/4π-electrocyclization strategy.

    PubMed

    Yan, Xiuxiang; Hu, Xiangdong

    2014-06-01

    A strategy to the 6-5-6 tricyclic scaffold of taiwaniaquinoids was established on the basis of a one-pot thermal ring expansion/4π-electrocyclization process. The efficiency of this methodology has been demonstrated through its application in the total synthesis of taiwaniaquinone H, which has been accomplished in three steps and 14% overall yield in a protecting-group-free manner starting from commercially available materials. PMID:24837463

  13. Synthesis and biological activity of novel 5'-arylamino-nucleosides by microwave-assisted one-pot tandem Staudinger/aza-Wittig/reduction.

    PubMed

    Chen, Hua; Zhao, Jianpeng; Li, Yanan; Shen, Fengjuan; Li, Xiaoliu; Yin, Qingmei; Qin, Zhanbin; Yan, Xinhao; Wang, Yanfei; Zhang, Pingzhu; Zhang, Jinchao

    2011-01-01

    Novel pseudonucleosides with benzylamino group on 5'-position (4) were synthesized by using the microwave-assisted one-pot tandem Staudinger/aza-Wittig/reduction reaction in good yields of 55.2-71.7%. The deacetylation of 4 afforded compounds 5. HIV-1 reverse transcriptase (RT) inhibitory and antitumor activities were preliminarily evaluated with 5. The results showed that the new pseudonucleosides (5) could effectively inhibit HIV-1 RT activity, but no antitumor activity. PMID:21095125

  14. New pyridinium-based ionic liquid as an excellent solvent-catalyst system for the one-pot three-component synthesis of 2,3-disubstituted quinolines.

    PubMed

    Anvar, Salma; Mohammadpoor-Baltork, Iraj; Tangestaninejad, Shahram; Moghadam, Majid; Mirkhani, Valiollah; Khosropour, Ahmad Reza; Landarani Isfahani, Amir; Kia, Reza

    2014-03-10

    The synthesis of a variety of 2,3-disubstituted quinolines has been achieved successfully via a one-pot three-component reaction of arylamines, arylaldehydes and aliphatic aldehydes in the presence of butylpyridinium tetrachloroindate(III), [bpy][InCl4], ionic liquid as a green catalyst and solvent. Mild conditions with excellent conversions, and simple product isolation procedure are noteworthy advantages of this method. The recyclability of the ionic liquid makes this protocol environmentally benign. PMID:24521525

  15. Chemo- and Enantioselective Addition and β-Hydrogen Transfer Reduction of Carbonyl Compounds with Diethylzinc Reagent in One Pot Catalyzed by a Single Chiral Organometallic Catalyst.

    PubMed

    Huang, Huayin; Zong, Hua; Bian, Guangling; Song, Ling

    2015-12-18

    Using a single chiral phosphoramide-Zn(II) complex as the catalyst, the asymmetric β-H transfer reduction of aromatic α-trifluoromethyl ketones and enantioselective addition of aromatic aldehydes with Et2Zn in one pot were successfully realized, affording the corresponding additive products of secondary alcohols in high yields (up to 99%) with excellent enantioselectivities (up to 98% ee) and the reduction products of α-trifluoromethyl alcohols in good to excellent yields with up to 77% ee. PMID:26579727

  16. One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular SN2 reaction.

    PubMed

    Xiong, Yiwen; Qian, Ping; Cao, Chenhui; Mei, Haibo; Han, Jianlin; Li, Guigen; Pan, Yi

    2014-01-01

    We report here an efficient one-pot method for the synthesis of α,β-differentiated diamino esters directly from cinnamate esters using N,N-dichloro-p-toluenesulfonamide and benzylamine as nitrogen sources. The key transformations include a Cu-catalyzed aminohalogenation and aziridination, followed by an intermolecular SN2 nucleophilic ring opening by benzylamine. The reactions feature a wide scope of substrates and proceed with excellent stereo- and regioselectivity (anti:syn >99:1) . PMID:25161740

  17. One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular SN2 reaction

    PubMed Central

    Xiong, Yiwen; Qian, Ping; Cao, Chenhui; Mei, Haibo; Li, Guigen

    2014-01-01

    Summary We report here an efficient one-pot method for the synthesis of α,β-differentiated diamino esters directly from cinnamate esters using N,N-dichloro-p-toluenesulfonamide and benzylamine as nitrogen sources. The key transformations include a Cu-catalyzed aminohalogenation and aziridination, followed by an intermolecular SN2 nucleophilic ring opening by benzylamine. The reactions feature a wide scope of substrates and proceed with excellent stereo- and regioselectivity (anti:syn >99:1) . PMID:25161740

  18. Synthesis of a Library of 1,5,2-Dithiazepine 1,1-Dioxides. Part 1: A One-Pot Sulfonylation/Thia-Michael Protocol

    PubMed Central

    Zang, Qin; Zhou, Aihua; Javed, Salim; Maity, Pradip K.; Knudtson, Chris A.; Bi, Danse; Hastings, Jared J.; Basha, Fatima Z.; Hanson, Paul R.

    2013-01-01

    A novel one-pot sulfonylation/intramolecular thia-Michael protocol is reported for the synthesis of 1,5,2-dithiazepine 1,1-dioxides. Sulfonylation between cysteine ethyl ester/cysteamine and 2-chloroethanesulfonyl chloride, followed by in situ intramolecular thia-Michael addition, was achieved and afforded the titled 1,5,2-dithiazepine-1,1-dioxide scaffolds. Diversification was demonstrated for future library synthesis. PMID:24385679

  19. One-pot synthesis of stable colloidal solutions of MFe{sub 2}O{sub 4} nanoparticles using oleylamine as solvent and stabilizer

    SciTech Connect

    Pérez-Mirabet, Leonardo; Solano, Eduardo; Martínez-Julián, Fernando; Guzmán, Roger; Arbiol, Jordi; Puig, Teresa; Obradors, Xavier; Pomar, Alberto; Yáñez, Ramón; Ros, Josep; Ricart, Susagna

    2013-03-15

    Highlights: ► One-pot synthesis of ferrite magnetic nanoparticles (<10 nm) in non-polar media. ► Nanoparticles present high monocrystal quality and monodispersion. ► Superparamagnetic behavior at room temperature. ► Nanoparticles transfer to polar media via ligand exchange. - Abstract: An easy, efficient, reproducible and scalable one-pot synthetic methodology to obtain magnetic spinel ferrite nanoparticles has been developed. This approach is based on one-pot thermal decomposition of Fe(acac){sub 3} and M(acac){sub 2} (M = Co, Mn, Cu and Zn) in oleylamine, which also acts as a capping ligand, by producing stable colloidal dispersions of nanoparticles in non-polar solvents. The properties of the nanoparticles have been studied via different techniques, such as transmission electron microscopy, which shows that nanoparticles are monocrystallines and a narrow dispersion in size; magnetic analyses have demonstrated that the resulting ferrite nanoparticles show high saturation values and superparamagnetic behavior at room temperature; X-ray diffraction has also been performed, and it confirms that the synthesized nanoparticles have a spinel structure. Complementarily, ligand exchange has been also carried out in order to produce dispersions of the synthesized nanoparticles in polar media.

  20. Recent advances in the chemistry of Rh carbenoids: multicomponent reactions of diazocarbonyl compounds

    NASA Astrophysics Data System (ADS)

    Medvedev, J. J.; Nikolaev, V. A.

    2015-07-01

    Multicomponent reactions of diazo compounds catalyzed by RhII complexes become a powerful tool for organic synthesis. They enable three- or four-step processes to be carried out as one-pot procedures (actually as one step) with high stereoselectivity to give complex organic molecules, including biologically active compounds. This review addresses recent results in the chemistry of Rh-catalyzed multicomponent reactions of diazocarbonyl compounds with the intermediate formation of N-, O- and C=O-ylides. The diastereo- and enantioselectivity of these reactions and the possibility of using various co-catalysts to increase the efficiency of the processes under consideration are discussed. The bibliography includes 120 references.

  1. A novel water-soluble fluorescent polymer based on perylene bisimides dyes: one-pot preparation and its bio-imaging.

    PubMed

    Tan, Haijian; Liu, Hongmei; Liu, Yaojun; Duan, Wenfeng; Yi, Xuegang; Wu, Yonggang; Zhao, Hongchi; Bai, Libin

    2016-04-01

    Perylene bisimides dye-based water-soluble fluorescent polymer P3, N,N'-bis(3-amyl)-1-bromo-7-{4'-[3''-(S-poly(N-acryloyl ethylene diamine hydrochloride)-2'''-methyl propionic acid)propionyloxy hexyloxy]phenyl} perylene-3,4:9,10-tetracarboxylic bisimides, was synthesized with polyelectrolyte modification via one-pot reaction (the reduction reaction of trithioester and click reaction between the thiol group and carbon-carbon double bond were simultaneously conducted in one pot with high conversion). One-pot method can overcome the limitation that usual click reaction between thiol and other groups has low conversion because thiol group is subject to rapid oxidation during purification and storage. Chemical, structural, and optical properties of P3 and intermediate products were fully characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared, gel permeation chromatograph, UV-vis spectra, and fluorescence spectra, respectively. The results revealed that P3 displayed excellent water solubility and not only exhibited red strong fluorescence emission band in water but also had the similar photoluminescent spectra to those of intermediate products (M4 and P2) in chloroform. Allowing for the potential application in biological detection field, cell viability and live cell imaging with the presence of P3 were further investigated with Hela cells. The results showed that P3 had low cytotoxicity with strong intracellular fluorescence entry. Meanwhile, with the augment of concentration of P3 (0-0.500 mg mL(-1)), the cell uptake and accumulation of P3 increased and thereby result in enhancement of the intracellular fluorescence. These experiment results suggested that P3 had enormous potential as a fluorescence probe to be an important component in biological detection field. PMID:26719068

  2. A facile one-pot hydrothermal synthesis of β-MnO{sub 2} nanopincers and their catalytic degradation of methylene blue

    SciTech Connect

    Cheng, Gao; Yu, Lin Lin, Ting; Yang, Runnong; Sun, Ming; Lan, Bang; Yang, Lili; Deng, Fangze

    2014-09-15

    Branched β-MnO{sub 2} bipods with novel nanopincer morphology were prepared by a facile one-pot hydrothermal method via a redox reaction between NaClO{sub 3} and MnSO{sub 4} in sulfuric acid solution without using any surfactants or templates. The products were characterized in detail by various techniques including X-ray powder diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, surface area analyzer, field emission scanning electron microscopy and transmission electron microscopy. Results show that the obtained β-MnO{sub 2} nanopincers consist of two sharp nanorods with a diameter of 100–200 nm and a length of 1–2 μm. The concentration of H{sub 2}SO{sub 4} solution plays an important role in controlling the crystal phase and morphology of the final product. A possible formation mechanism for the β-MnO{sub 2} nanopincers was proposed. Moreover, these β-MnO{sub 2} nanostructures exhibited better catalytic performance than the commercial MnO{sub 2} particles to decompose methyl blue (MB) in the presence of H{sub 2}O{sub 2}. - Graphical abstract: Branched β-MnO{sub 2} bipods with novel nanopincer morphology were prepared by a facile one-pot hydrothermal method through oxidizing MnSO{sub 4} with NaClO{sub 3} in H2SO{sub 4} condition without using any surfactants or templates. - Highlights: {sup •} Branched β-MnO{sub 2} nanopincers were prepared by a facile one-pot hydrothermal method. {sup •} Morphology and crystal phase of MnO{sub 2} were controlled by the H{sub 2}SO{sub 4} concentration. {sup •} A possible formation mechanism for the obtained β-MnO{sub 2} nanopincers was proposed. {sup •} The products showed great catalytic performance in degradation of methylene blue.

  3. Asymmetric, Three-Component, One-Pot Synthesis of Spiropyrazolones and 2,5-Chromenediones from Aldol Condensation/NHC-Catalyzed Annulation Reactions.

    PubMed

    Wang, Lei; Li, Sun; Chauhan, Pankaj; Hack, Daniel; Philipps, Arne R; Puttreddy, Rakesh; Rissanen, Kari; Raabe, Gerhard; Enders, Dieter

    2016-04-01

    A novel one-pot, three-component diastereo- and enantioselective synthesis of spiropyrazolones has been developed involving the aldol condensation of an enal to generate α,β-unsaturated pyrazolones, which react with a second equivalent of enal through an N-heterocyclic carbene (NHC)-catalyzed [3+2] annulation. The desired spirocyclopentane pyrazolones are obtained in moderate to good yields and good to excellent stereoselectivities. Alternatively, starting from cyclic 1,3-diketones, 2,5-chromenediones are available through [2+4] annulation. PMID:26864437

  4. One-pot green synthesis of 1,3,5-triarylpentane-1,5-dione and triarylmethane derivatives as a new class of tyrosinase inhibitors.

    PubMed

    Zheng, Zong-Ping; Zhang, Yi-Nan; Zhang, Shuang; Chen, Jie

    2016-02-01

    A new method was developed for one-pot green synthesis 1,3,5-triarylpentane-1,5-dione, triarylmethane, and flavonoid derivatives from the reaction between 2,4-dihydroxybenzaldehyde and hydroxyacetophenones via Aldol, Michael, and Friedel-Crafts additions using boric acid as catalyst in polyethylene glycol 400. The synthetic compounds demonstrated significant tyrosinase inhibitory activities much stronger than that of kojic acid. More important, 1,3,5-triarylpentane-1,5-dione and triarylmethane derivatives were found to be a new class of tyrosinase inhibitors. PMID:26754613

  5. Tetraethylene glycol promoted two-step, one-pot rapid synthesis of indole-3-[1-11C]acetic acid

    SciTech Connect

    Lee, Sojeong; Qu, Wenchao; Alexoff, David L.; Shea, Colleen; Kim, Dohyun; Schueller, Michael; Fowler, Joanna S.

    2014-12-12

    An operationally friendly, two-step, one-pot process has been developed for the rapid synthesis of carbon-11 labeled indole-3-acetic acid ([11]IAA or [11]auxin). By replacing an aprotic polar solvent with tetraethylene glycol, nucleophilic [11]cyanation and alkaline hydrolysis reactions were performed consecutively in a single pot without a time-consuming intermediate purification step. The entire production time for this updated procedure is 55 min, which dramatically simplifies the entire synthesis and reduces the starting radioactivity required for a whole plant imaging study.

  6. Alkenes as azido precursors for the one-pot synthesis of 1,2,3-triazoles catalyzed by copper nanoparticles on activated carbon.

    PubMed

    Alonso, Francisco; Moglie, Yanina; Radivoy, Gabriel; Yus, Miguel

    2013-05-17

    A one-pot protocol for the synthesis of 1,2,3-triazoles has been developed starting from inactivated alkenes and based on two click reactions: the azidosulfenylation of the carbon-carbon double bond and the copper-catalyzed azide-alkyne cycloaddition (CuAAC). High yields of the β-methylsulfanyl triazoles have been attained using CuNPs/C as catalyst, with other commercial copper catalysts being completely inactive. The versatility of the methylsulfanyl group has been demonstrated through a series of synthetic transformations, including direct access to 1-vinyl and 4-monosubstituted triazoles. PMID:23617398

  7. One-pot wet-chemical co-reduction synthesis of bimetallic gold-platinum nanochains supported on reduced graphene oxide with enhanced electrocatalytic activity

    NASA Astrophysics Data System (ADS)

    Chen, De-Jun; Zhang, Qian-Li; Feng, Jin-Xia; Ju, Ke-Jian; Wang, Ai-Jun; Wei, Jie; Feng, Jiu-Ju

    2015-08-01

    In this work, a simple, rapid and facile one-pot wet-chemical co-reduction method is developed for synthesis of bimetallic Au-Pt alloyed nanochains supported on reduced graphene oxide (Au-Pt NCs/RGO), in which caffeine is acted as a capping agent and a structure-directing agent, while no any seed, template, surfactant or polymer involved. The as-prepared nanocomposites display enlarged electrochemical active surface area, significantly enhanced catalytic activity and better stability for methanol and ethylene glycol oxidation, compared with commercial Pt-C (Pt 50 wt%), PtRu-C (Pt 30 wt% and Ru 15 wt%) and Pt black.

  8. DABCO-catalyzed one-pot three component synthesis of dihydropyrano[3,2-c]chromene substituted quinazolines and their evaluation towards anticancer activity.

    PubMed

    Vodnala, Sumathi; Bhavani, A K D; Kamutam, Ramakrishna; Naidu, V G M; Promila; Prabhakar, Ch

    2016-08-15

    A facile DABCO promoted one-pot three component synthesis of a new series of C-C linked bis-heterocycle containing dihydropyrano[c]chromene as highly fused oxa-heteryl group at C-2 position of quinazoline was developed. Quinazoline-2-carbaldehyde, substituted 4-hydroxycoumarin and ethyl cyanoacetate were used as key components in the Knoevenagel-Michael addition reaction to get the titled compounds. These compounds were screened for anti-cancer activity against the breast cancer cell lines of MDA-MB 231, and MDA-MB 453. PMID:27432765

  9. Synthesis and Evaluation of Cu/SAPO-34 Catalysts for NH3-SCR 2: Solid-state Ion Exchange and One-pot Synthesis

    SciTech Connect

    Gao, Feng; Walter, Eric D.; Washton, Nancy M.; Szanyi, Janos; Peden, Charles HF

    2015-01-01

    Cu-SAPO-34 catalysts are synthesized using two methods: solid-state ion exchange (SSIE) and one-pot synthesis. SSIE is conducted by calcining SAPO-34/CuO mixtures at elevated temperatures. For the one-pot synthesis method, Cu-containing chemicals (CuO and CuSO4) are added during gel preparation. A high-temperature calcination step is also needed for this method. Catalysts are characterized with surface area/pore volume measurements, temperature programmed reduction (TPR), electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopies, and scanning electron microscopy (SEM). Catalytic properties are examined using standard ammonia selective catalytic reduction (NH3-SCR) and ammonia oxidation reactions. In Cu-SAPO-34 samples formed using SSIE, Cu presents both as isolated Cu2+ ions and unreacted CuO. The former is highly active and selective in NH3-SCR, while the latter catalyzes a side reaction; notably, the non-selective oxidation of NH3 above 350 ºC. Using the one-pot method followed by a high-temperature aging treatment, it is possible to form Cu SAPO-34 samples with predominately isolated Cu2+ ions at low Cu loadings. However at much higher Cu loadings, isolated Cu2+ ions that bind weakly with the CHA framework and CuO clusters also form. These Cu moieties are very active in catalyzing non-selective NH3 oxidation above 350 ºC. Low-temperature reaction kinetics indicate that Cu-SAPO-34 samples formed using SSIE have core-shell structures where Cu is enriched in the shell layers; while Cu is more evenly distributed within the one-pot samples. Reaction kinetics also suggest that at low temperatures, the local environment next to Cu2+ ion centers plays little role on the overall catalytic properties. The authors gratefully acknowledge the US Department of Energy (DOE), Energy Efficiency and Renewable Energy, Vehicle Technologies Office for the support of this work. The research described in this paper was performed at the Environmental

  10. One-pot synthesis of single-crystal Pt nanoplates uniformly deposited on reduced graphene oxide, and their high activity and stability on the electrocalalytic oxidation of methanol.

    PubMed

    Hao, Yanfei; Wang, Xudan; Shen, Jianfeng; Yuan, Junhua; Wang, Ai-Jun; Niu, Li; Huang, Shengtang

    2016-04-01

    We demonstrate a one-pot thermoreduction approach towards the preparation of single-crystal Pt nanoplates, which were uniformly deposited on the reduced graphene oxide (RGO) using polyvinylpyrrolidone (PVP) as a stabilizer. The size of Pt nanoplates can be tuned from 6.8 to 10.1 nm by controlling Pt loading. The as-prepared Pt/PVP/RGO catalysts show high stability and activity towards the methanol oxidation reaction (MOR). Their MOR current can reach up to 401 mA mg(-1) Pt and MOR current can maintain 89.4% of its initial value after 10 000 potential cycles. PMID:26906081

  11. Synthesis of 1,2,3-Substituted Pyrroles from Propargylamines via a One-Pot Tandem Enyne Cross Metathesis-Cyclization Reaction.

    PubMed

    Chachignon, Helene; Scalacci, Nicolò; Petricci, Elena; Castagnolo, Daniele

    2015-05-15

    Enyne cross metathesis of propargylamines with ethyl vinyl ether enables the one-pot synthesis of substituted pyrroles. A series of substituted pyrroles, bearing alkyl, aryl, and heteroaryl substituents, has been synthesized in good yields under microwave irradiation. The reactions are rapid and procedurally simple and also represent a facile entry to the synthetically challenging 1,2,3-substituted pyrroles. The value of the methodology is further corroborated by the conversion of pyrroles into 3-methyl-pyrrolines and the derivatization of the 3-methyl-substituent arising from the metathesis reaction. PMID:25897951

  12. Mechanochemical solid-state synthesis of 2-aminothiazoles, quinoxalines and benzoylbenzofurans from ketones by one-pot sequential acid- and base-mediated reactions.

    PubMed

    Nagarajaiah, Honnappa; Mishra, Abhaya Kumar; Moorthy, Jarugu Narasimha

    2016-04-26

    α-Chloroketones - obtained by the atom-economical chlorination of ketones with trichloroisocyanuric acid (TCCA) in the presence of p-TSA under ball-milling conditions - were set up for a sequential base-mediated condensation reaction with thiourea/thiosemicarbazides, o-phenylenediamine and salicylaldehyde to afford 2-aminothiazoles, 2-hydrazinylthiazoles, quinoxalines and benzoylbenzofurans, respectively, in respectable yields. The viability of one-pot sequential acid- and base-mediated reactions in the solid state under ball-milling conditions is thus demonstrated. PMID:27072599

  13. Novel functional conjugative hyperbranched polymers with aggregation-induced emission: synthesis through one-pot "A2+B4" polymerization and application as explosive chemsensors and PLEDs.

    PubMed

    Wu, Wenbo; Ye, Shanghui; Yu, Gui; Liu, Yunqi; Qin, Jingui; Li, Zhen

    2012-01-01

    With the aim to develop new tetraphenylethylene (TPE)-based conjugated hyperbranched polymer, TPE units, one famous aggregation-induced emission (AIE) active group, are utilized to construct hyperbranched polymers with three other aromatic blocks, through an "A2+B4" approach by using one-pot Suzuki polycondensation reaction. These three hyperbranched polymers exhibit interesting AIEE behavior and act as explosive chemsensors with high sensitivity both in the nanoparticles and solid states. This is the first report of the AIE activity of the TPE-based conjugated hyperbranched polymers. Their corresponding PLED devices also demonstrate good performance. PMID:22134953

  14. Synthesis and mechanism study of CdS quantum dots in two-phase liquid/liquid interfaces via one-pot route

    NASA Astrophysics Data System (ADS)

    Wang, Jidong; Guo, Kehong; Ke, Dandan; Han, Shumin

    2015-01-01

    The present letter reports a facile synthetic strategy in octadecene(ODE)/glycerol interfaces to prepare CdS quantum dots (QDs) with bright bandgap emission. In this synthesis, the precursors were not synthesized as a preceding step, but all chemicals were reacted simultaneously in a one-pot reaction. The monodispersed CdS QDs were synthesized in ODE/glycerol interfaces at 140, 160 and 180 °C, respectively. The thermodynamic equilibrium was proposed to explain the growth mechanism of CdS QDs in the ODE/glycerol interfaces.

  15. One-pot synthesis of monodisperse palladium-copper nanocrystals supported on reduced graphene oxide nanosheets with improved catalytic activity and methanol tolerance for oxygen reduction reaction

    NASA Astrophysics Data System (ADS)

    Lv, Jing-Jing; Li, Shan-Shan; Wang, Ai-Jun; Mei, Li-Ping; Feng, Jiu-Ju; Chen, Jian-Rong; Chen, Zhaojiang

    2014-12-01

    Monodisperse bimetallic alloyed palladium-copper nanocrystals are uniformly supported on reduced graphene oxide nanosheets by a one-pot solvothermal strategy, with an average size of 6.81 nm. As a result, the as-prepared nanocomposites have the enlarged electrochemically active surface area (49.2 m2 g-1), and display the improved electrocatalytic performance and high methanol-tolerance ability for oxygen reduction reaction in alkaline media, compared with commercial Pd black and RGOs. Those RGOs-supporting Pd-Cu alloys would have potential applications in fuel cells.

  16. One-pot synthesis of 2,5-dihydropyrroles from terminal alkynes, azides, and propargylic alcohols by relay actions of copper, rhodium, and gold.

    PubMed

    Miura, Tomoya; Tanaka, Takamasa; Matsumoto, Kohei; Murakami, Masahiro

    2014-12-01

    Relay actions of copper, rhodium, and gold formulate a one-pot multistep pathway, which directly gives 2,5-dihydropyrroles starting from terminal alkynes, sulfonyl azides, and propargylic alcohols. Initially, copper-catalyzed 1,3-dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1-sulfonyl-1,2,3-triazoles, which then react with propargylic alcohols under the catalysis of rhodium. The resulting alkenyl propargyl ethers subsequently undergo the thermal Claisen rearrangement to give α-allenyl-α-amino ketones. Finally, a gold catalyst prompts 5-endo cyclization to produce 2,5-dihydropyrroles. PMID:25345587

  17. Copper ferrite nanoparticles: an efficient and reusable nanocatalyst for a green one-pot, three-component synthesis of spirooxindoles in water.

    PubMed

    Bazgir, Ayoob; Hosseini, Ghaffar; Ghahremanzadeh, Ramin

    2013-10-14

    A green reaction of isatins, active cyanomethanes, and cyclic 1,3-dicarbonyl derivatives for the efficient and simple one-pot three-component synthesis of spirooxindole fused heterocycles in refluxing water by use of magnetically recoverable and reusable catalyst is reported. The features of this procedure are, the use of magnetically recoverable and reusable catalyst, mild reaction conditions, high to excellent product yields, operational simplicity, and easy workup procedures. Most importantly of all, easy magnetic separation of the catalyst eliminates the requirement of catalyst filtration after completion of the reaction. Furthermore, the catalyst remained highly active even after 5 repeated uses. PMID:24050156

  18. Pseudo five-component synthesis of 2,5-di(hetero)arylthiophenes via a one-pot Sonogashira–Glaser cyclization sequence

    PubMed Central

    Urselmann, Dominik; Antovic, Dragutin

    2011-01-01

    Summary Based upon a consecutive one-pot Sonogashira–Glaser coupling–cyclization sequence a variety of 2,5-di(hetero)arylthiophenes were synthesized in moderate to good yields. A single Pd/Cu-catalyst system, without further catalyst addition, and easily available, stable starting materials were used, resulting in a concise and highly efficient route for the synthesis of the title compounds. This novel pseudo five-component synthesis starting from iodo(hetero)arenes is particularly suitable as a direct access to well-defined thiophene oligomers, which are of peculiar interest in materials science. PMID:22238523

  19. One-pot synthesis of 3,4,5-trisubstituted 1,2,4-triazoles via the addition of hydrazides to activated secondary amides.

    PubMed

    Bechara, William S; Khazhieva, Inna S; Rodriguez, Elsa; Charette, André B

    2015-03-01

    A general approach has been developed for the one-pot synthesis of 3,4,5-trisubstituted 1,2,4-triazoles from secondary amides and hydrazides via triflic anhydride activation followed by microwave-induced cyclodehydration. In addition, the 1,2,4-triazole moiety is shown to be a useful directing group for Ru-catalyzed C-H arylation. Access to 1,2,4-triazolophenanthridine can be achieved from the reaction products using a Pd-catalyzed intramolecular C-H functionalization reaction. PMID:25700199

  20. One-Pot Synthesis of N-(α-Peroxy)Indole/Carbazole via Chemoselective Three-Component Condensation Reaction in Open Atmosphere.

    PubMed

    Wang, Xinbo; Pan, Yupeng; Huang, Kuo-Wei; Lai, Zhiping

    2015-11-20

    A facile one-pot synthesis of N-(α-peroxy)indole and N-(α-peroxy)carbazole has been developed using metal-free, organo-acid-catalyzed three-component condensation reactions of indole/carbazole, aldehyde, and peroxide. Based on the reaction discovered, a new synthetic proposal for Fumitremorgin A and Verruculogen is introduced. Such a protocol could be easily handled and scaled up in an open atmosphere with a wide substrate scope, enabling the construction of a new molecule library. PMID:26541059

  1. Tetraethylene glycol promoted two-step, one-pot rapid synthesis of indole-3-[1-11C]acetic acid

    DOE PAGESBeta

    Lee, Sojeong; Qu, Wenchao; Alexoff, David L.; Shea, Colleen; Kim, Dohyun; Schueller, Michael; Fowler, Joanna S.

    2014-12-12

    An operationally friendly, two-step, one-pot process has been developed for the rapid synthesis of carbon-11 labeled indole-3-acetic acid ([11]IAA or [11]auxin). By replacing an aprotic polar solvent with tetraethylene glycol, nucleophilic [11]cyanation and alkaline hydrolysis reactions were performed consecutively in a single pot without a time-consuming intermediate purification step. The entire production time for this updated procedure is 55 min, which dramatically simplifies the entire synthesis and reduces the starting radioactivity required for a whole plant imaging study.

  2. Chiroptical Probing of Lanthanide-Directed Self-Assembly Formation Using btp Ligands Formed in One-Pot Diazo-Transfer/Deprotection Click Reaction from Chiral Amines.

    PubMed

    Byrne, Joseph P; Martínez-Calvo, Miguel; Peacock, Robert D; Gunnlaugsson, Thorfinnur

    2016-01-11

    A series of enantiomeric 2,6-bis(1,2,3-triazol-4-yl)pyridines (btp)-containing ligands was synthesized by a one-pot two-step copper-catalyzed amine/alkyne click reaction. The Eu(III) - and Tb(III) -directed self-assembly formation of these ligands was studied in CH3 CN by monitoring their various photophysical properties, including their emerging circular dichroism and circularly polarized luminescence. The global analysis of the former enabled the determination of both the stoichiometry and the stability constants of the various chiral supramolecular species in solution. PMID:26555573

  3. A mild, one-pot Stadler-Ziegler synthesis of arylsulfides facilitated by photoredox catalysis in batch and continuous-flow.

    PubMed

    Wang, Xiao; Cuny, Gregory D; Noël, Timothy

    2013-07-22

    Visible advance: A mild, one-pot Stadler-Ziegler process for C-S bond formation has been developed. The method employs the photoredox catalyst [Ru(bpy)3Cl2]⋅6 H2O irradiated with visible light. A variety of aryl-alkyl and diaryl sulfides were prepared from readily available arylamines and aryl/alkylthiols in good yields. The use of a photo microreactor led to a significant improvement with respect to safety and efficiency. PMID:23784666

  4. Conservation Laws and Mixed-Type Vector Solitons for the 3-Coupled Variable-Coefficient Nonlinear Schrödinger Equations in Inhomogeneous Multicomponent Optical Fibre

    NASA Astrophysics Data System (ADS)

    Chai, Jun; Tian, Bo; Wang, Yu-Feng; Sun, Wen-Rong; Wang, Yun-Po

    2016-06-01

    In this article, the propagation and collision of vector solitons are investigated from the 3-coupled variable-coefficient nonlinear Schrödinger equations, which describe the amplification or attenuation of the picosecond pulses in the inhomogeneous multicomponent optical fibre with different frequencies or polarizations. On the basis of the Lax pair, infinitely-many conservation laws are obtained. Under an integrability constraint among the variable coefficients for the group velocity dispersion (GVD), nonlinearity and fibre gain/loss, and two mixed-type (2-bright-1-dark and 1-bright-2-dark) vector one- and two-soliton solutions are derived via the Hirota method and symbolic computation. Influence of the variable coefficients for the GVD and nonlinearity on the vector soliton amplitudes and velocities is analysed. Through the asymptotic and graphic analysis, bound states and elastic and inelastic collisions between the vector two solitons are investigated: Not only the elastic but also inelastic collision between the 2-bright-1-dark vector two solitons can occur, whereas the collision between the 1-bright-2-dark vector two solitons is always elastic; for the bound states, the GVD and nonlinearity affect their types; with the GVD and nonlinearity being the constants, collision period decreases as the GVD increases but is independent of the nonlinearity.

  5. One-pot SSA-catalyzed β-elimination: An efficient and inexpensive protocol for easy access to the glycal of sialic acid

    PubMed Central

    Paragas, Erickson M.; Monreal, I. Abrrey; Vasil, Chris M.; Saludes, Jonel P.

    2014-01-01

    Neu5Ac2en1Me per-OAc, the fully protected glycal of sialic acid, is a key intermediate in the discovery of therapeutics and diagnostics, including anti-influenza drugs and proteolysis resistant peptidomimetic foldamers. The synthesis of this sialic acid derivative, however, still relies on standard sugar chemistry that utilizes multi-step methodologies. Herein we report a facile and highly efficient microwave-assisted preparation of Neu5Ac1Me using silica sulfuric acid (SSA) as solid-supported acid catalyst that is one- to two-orders of magnitude faster than standard procedures. We also describe the microwave-assisted and SSA-catalyzed one-pot, rapid, solvent free reaction that combines both peracetylation and β-elimination reactions in one step to generate the glycal from Neu5Ac1Me. We coined the term One-pot SSA-catalyzed Technology for β-Elimination Protocol (OneSTEP) to describe this least laborious, most efficient, and practical preparation to date of Neu5Ac2en1Me per-OAc in terms of yield, time, reagent cost, and waste generation. PMID:25497336

  6. A general one-pot strategy for the synthesis of high-performance transparent-conducting-oxide nanocrystal inks for all-solution-processed devices.

    PubMed

    Song, Jizhong; Kulinich, Sergei A; Li, Jianhai; Liu, Yanli; Zeng, Haibo

    2015-01-01

    For all-solution-processed (ASP) devices, transparent conducting oxide (TCO) nanocrystal (NC) inks are anticipated as the next-generation electrodes to replace both those synthesized by sputtering techniques and those consisting of rare metals, but a universal and one-pot method to prepare these inks is still lacking. A universal one-pot strategy is now described; through simply heating a mixture of metal-organic precursors a wide range of TCO NC inks, which can be assembled into high-performance electrodes for use in ASP optoelectronics, were synthesized. This method can be used for various oxide NC inks with yields as high as 10 g. The formed NCs are of high crystallinity, uniform morphology, monodispersity, and high ink stability and feature effective doping. Therefore, the inks can be readily assembled into films with a surface roughness of 1.6 nm. Typically, a sheet resistance of 110 Ω sq(-1) can be achieved with a transmittance of 88%, which is the best performance for TCO NC ink-based electrodes described to date. These electrodes can thus drive a polymer light-emitting diode (PLED) with a luminance of 2200 cd m(-2) at 100 mA cm(-2). PMID:25403980

  7. Ag(I)-triggered one-pot synthesis of Ag nanoparticles onto natural nanorods as a multifunctional nanocomposite for efficient catalysis and adsorption.

    PubMed

    Tian, Guangyan; Wang, Wenbo; Mu, Bin; Kang, Yuru; Wang, Aiqin

    2016-07-01

    A multifunctional palygorskite/polyaniline/Ag nanoparticles (PAL/PANI/AgNPs) nanocomposite was prepared at room temperature using a simple one-pot in-situ polymerization reaction of aniline monomers triggered by Ag(I) on the surface of natural PAL nanorods. Ag(I) served as both the oxidant and the precursor of the AgNPs, which initiated the polymerization of aniline monomers on PAL nanorods while simultaneously being reduced to form Ag(0) nanoparticles (AgNPs). The in-situ formed AgNPs were evenly distributed on the surface of the PAL nanorods because the interfacial effect of PAL prevents their aggregation. The density and size of the AgNPs and the catalytic activity of the nanocomposites could be controlled by altering the molar ratio of aniline to Ag(I). The performance evaluation revealed that the nanocomposites could be used as highly active catalysts, which rapidly catalyzed the reduction of 4-nitrophenol (4-NP) within 2min and Congo red (CR) within 10min. The nanocomposites are also an effective adsorbent for H2PO4(-) able to remove 99.40% of H2PO4(-) (only 61.77% for raw PAL) from a solution with an initial concentration of 50mg/L. This multifunctional nanocomposite synthesized by a simple one-pot approach is a promising material for environmental applications. PMID:27054770

  8. Ultrasonic-assisted one-pot preparation of ZnO/Ag3VO4 nanocomposites for efficiently degradation of organic pollutants under visible-light irradiation

    NASA Astrophysics Data System (ADS)

    Kiantazh, Fariba; Habibi-Yangjeh, Aziz

    2015-11-01

    We report a facile ultrasonic-assisted one-pot method for preparation of ZnO/Ag3VO4 nanocomposites with different mole fractions of silver vanadate. The preparation method has considerable merits such as short preparation time, large-scale, and one-pot strategy. The resultant samples were fairly characterized by means of XRD, EDX, SEM, TEM, UV-vis DRS, FT-IR, and PL techniques. Visible-light activity of the resultant samples was investigated by degradation of rhodamine B (RhB), methylene blue (MB), and methyl orange (MO). Among the prepared nanocomposites, the ZnO/Ag3VO4 nanocomposite with 0.073 mole fraction of Ag3VO4 exhibited the best activity and excessive amount of Ag3VO4 resulted in decrease of the activity. Photocatalytic activity of this nanocomposite under visible-light irradiation is about 21, 56, and 2.8-fold higher than that of the ZnO sample in degradation of RhB, MB, and MO, respectively. The highly enhanced activity of the nanocomposite was attributed to greater generation of electron-hole pairs, due to photosensitizing role of Ag3VO4 under visible-light irradiation, and efficiently separation of the photogenerated electron-hole pairs, due to formation of n-n heterojunction between the counterparts. Furthermore, it was revealed that the photocatalytic activity largely depends on ultrasonic irradiation time, calcination temperature, and scavengers of the reactive species.

  9. A new one-pot strategy to LaF3:Ce,Tb@SiO2 core-shell nanostructures

    NASA Astrophysics Data System (ADS)

    Liu, Lina; Sun, Ruirui; Zhang, Yongsheng; Qin, Ruifei; Zhang, Dongmei; Tang, Chunjuan; Chen, Linfeng; Liu, Lishuang

    2015-10-01

    LaF3:Ce,Tb@SiO2 core-shell nanostructures were synthesized using a new one-pot reverse microemulsion strategy. One-pot method facilitates the synthetic process of this kind of core-shell nanostructures. The crystalline phase, size, morphology, pore structure and luminescence properties were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen physisorption isotherm, photoluminescence (PL) excitation and emission spectra. The results revealed that the core-shell nanostructures have an average diameter of about 27 nm and cores of about 3 nm, and that these nanostructures contain micropores with an average pore diameter of 0.43 nm. The characteristic emissions of Tb3+ were observed under the excitation of Ce3+ 4f-5d transition due to the energy transfer from Ce3+ to Tb3+. LaF3:Ce,Tb@SiO2 nanostructures can disperse well in water and the colloid can emit bright green light under ultraviolet (UV) irradiation.

  10. Facile synthesis of core-shell/hollow anisotropic particles via control of cross-linking during one-pot dispersion polymerization.

    PubMed

    Liu, Yanan; Ma, Yuhong; Liu, Lianying; Yang, Wantai

    2015-05-01

    Preparation of anisotropic particles based on seed phase separation involves multiple processes, and asymmetrical structures and surfaces cannot be produced when anisotropic shapes emerge. In conventional one-pot dispersion polymerization (Dis.P) using cross-linker, only spherical particles are prepared due to rapid and high cross-linking. Herein, monodisperse snowman-like particles with core-shell/hollow structures and partially rough surface were synthesized straightforward by a modified one-pot Dis.P, in which ethylene glycol and water (6/4, vol.) were used as medium, and ammonium persulfate (APS) aqueous solution, vinyl acetate (VA) and/or acrylic acid (AA), divinylbenzene (DVB) and styrene (St) were added at 6h. The cross-linking of growing particles was confined to exterior (forming cross-linked shell), and gel contents were low, leading to phase separation. Asymmetrical morphologies, structures, sizes and surface roughness were flexibly tuned by varying amounts of APS, VA and/or AA, water and DVB, and DVB adding speed. At low APS contents or high DVB amounts, the inhomogeneous cross-linking of head enabled its phase to separate, producing elongated head. With addition of VA and AA, phase separations inside head and body were induced, generating hollow structure. Adding DVB very slowly, nonlinear growth of third compartment occurred, forming bowed head. PMID:25626132

  11. One-pot synthesis and visible light photocatalytic activity of monodispersed AgIn{sub 5}S{sub 8} microspheres

    SciTech Connect

    Li, Xiangqing; Wang, Lei; Wei, Dailong; Kang, Shizhao; Mu, Jin

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ► Monodispersed AgIn{sub 5}S{sub 8} microspheres were prepared in a one-pot process. ► The process is environmental friendly. ► The AgIn{sub 5}S{sub 8} microspheres display high photocatalytic activity. -- Abstract: Monodispersed AgIn{sub 5}S{sub 8} microspheres were synthesized using a one-pot solution method and characterized with X-ray diffraction, UV–vis diffuse reflectance spectroscopy, scanning electron microscope, energy dispersive X-ray spectroscopy and N{sub 2} adsorption–desorption isotherm. The results indicated that the AgIn{sub 5}S{sub 8} microspheres were of cubic spinel structure and the mean diameter of about 0.5 μm. In addition, the visible light photocatalytic activity of AgIn{sub 5}S{sub 8} microspheres was also investigated at room temperature. The AgIn{sub 5}S{sub 8} microspheres showed very high photocatalytic activity for the degradation of methyl orange with a degradation efficiency of about 98% under visible light irradiation for 20 min.

  12. One-Pot Approach to Organo-Phosphorus-Chalcogen Macrocycles Incorporating Double OP(S)SCn or OP(Se)SeCn Scaffolds: A Synthetic and Structural Study.

    PubMed

    Hua, Guoxiong; Du, Junyi; Slawin, Alexandra M Z; Woollins, J Derek

    2016-06-01

    The development of new methodology for the preparation of functional macrocycles with practical applications is an important research area in macromolecular science. In this study, we report a new one-pot route for the synthesis of a series of macro-heterocycles by incorporating two phosphorus atoms and two chalcogen atoms and two oxygen atoms (double OP(S)SCn or OP(Se)SeCn scaffolds). The three-component condensation reactions of 2,4-diferrocenyl-1,3,2,4-diathiadiphosphetane 2,4-disulfide (FcLR, a ferrocene analogue of Lawesson's reagent) or 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (LR, Lawesson's reagent), or 2,4-diphenyl-1,3,2,4-diselenadiphosphetane 2,4-diselenide (WR, Woollins' reagent), disodium alkenyl-diols, and dihalogenated alkanes are performed, giving rise to soluble and air or moisture-stable macrocycles in good-to-excellent yields (up to 92 %). This is the first systemically preparative and readily scalable example of one-pot ring opening/ring extending reaction of three-components to prepare phosphorus-chalcogen containing macrocycles. We also provide a systematic crystallographic study. PMID:27112964

  13. Facile one-pot surfactant-free synthesis of uniform Pd6Co nanocrystals on 3D graphene as an efficient electrocatalyst toward formic acid oxidation

    NASA Astrophysics Data System (ADS)

    Zhang, Lian Ying; Zhao, Zhi Liang; Yuan, Weiyong; Li, Chang Ming

    2016-01-01

    Ultrasmall and uniform Pd6Co nanocrystals were deposited on 3D graphene by a facile one-pot surfactant-free route for a catalyst toward formic acid oxidation, showing a much higher electrocatalytic activity, larger peak current density and better stability than Pd/3DG, Pd/C as well as commercial Pd-C, and thus offering great potential for an efficient anode catalyst toward high performance direct formic acid fuel cells.Ultrasmall and uniform Pd6Co nanocrystals were deposited on 3D graphene by a facile one-pot surfactant-free route for a catalyst toward formic acid oxidation, showing a much higher electrocatalytic activity, larger peak current density and better stability than Pd/3DG, Pd/C as well as commercial Pd-C, and thus offering great potential for an efficient anode catalyst toward high performance direct formic acid fuel cells. Electronic supplementary information (ESI) available: Experimental section and supplementary figures. See DOI: 10.1039/c5nr08512h

  14. Ferroic Properties in Individual and Multi-Component Nanostructures: The Influence of Size, Shape, and Interfacial Coupling

    NASA Astrophysics Data System (ADS)

    Johnson, Stephanie Howell

    Extrinsic magnetoelectric heterostructure materials receive increased interest because of the potential to tune the magnetoelectric properties through material selection and actively, through applied electric and magnetic field. Understanding the strength of the coupling of ferroic properties in composite solids and the roles of size, shape, and arrangement of the constituent phases is central to realizing high-performance magnetoelectrics and their applications. Nanoscale magnetoelectric materials are excellent candidate systems to study the aforementioned effects of shape and finite size, to meet the growing demand for faster, more efficient, low cost, and above all smaller device components for use in advanced magnetic memories, actuators, transducers, and sensors. Nanoscale materials offer increased interfacial surface area compared with bulk, making them appealing in the design of an enhanced magnetoelectric composite because the magnetoelectric effect in a composite system is driven by interfacial coupling mechanisms. However, nanoscale (approximately 100 nm or less) ferroic materials often exhibit a dimensionality-dependent suppression of ferroic and piezoelectric properties below a critical size. By controlling e.g. the surface chemical environment, introducing strain engineering of films through epitaxy or through the shape of a nanostructure, the ferroelectric phase stability can be tuned for a given material and temperature. In this dissertation nanoscale ferroic and multiferroic properties were investigated, highlighting five characteristic systems: ferromagnetic nanoparticles, ferroelectric nanocubes, extrinsic magnetoelectric nanowires, and resonant beams and resonant membranes. An experimental study of ferromagnetic nanoparticles is presented to underscore the importance of understanding the growth and interfacial coupling mechanisms in ferromagnetic nanoparticle systems. To investigate the finite-size driven ferroelectric phase transition at the

  15. One-pot synthesis of crosslinked amphiphilic polycarbonates as stable but reduction-sensitive carriers for doxorubicin delivery

    NASA Astrophysics Data System (ADS)

    Yi, Xiaoqing; Zhang, Quan; Dong, Hui; Zhao, Dan; Xu, Jia-qi; Zhuo, Renxi; Li, Feng

    2015-10-01

    In this paper, we first synthesized a novel disulfide-coupled bis-(cyclic carbonate) (TDCSS) monomer. After ring-opening co-polymerization (ROP) of TDCSS and trimethylene carbonate (TMC) initiated by mono-methoxyl poly(ethylene glycol), the crosslinked reduction-sensitive copolymer PEG-P(TMC-co-TDCSS) was obtained via a facile one-step procedure for efficient delivery of doxorubicin (DOX) into cancer cells. To serve as controls, PEG-P(TMC-co-TDCCC), which has an analogous structure without disulfide bond, and a linear polymer PEG-PTMC were also prepared. The copolymers could self-assemble to form nano-sized micelles in an aqueous solution. As compared to PEG-PTMC, crosslinked PEG-P(TMC-co-TDCSS) and PEG-P(TMC-co-TDCCC) showed lower CMC values and thus induced a much better micelle-forming ability. In vitro release studies revealed that the drug release behavior of DOX-loaded PEG-P(TMC-co-TDCSS) micelles, which could be accelerated in the presence of 10 mM dithiothreitol (DTT), showed a similar trend in the absence of DTT compared to DOX-loaded PEG-P(TMC-co-TDCCC) micelles. Furthermore, confocal laser scanning microscopy (CLSM) indicated that DOX-loaded PEG-P(TMC-co-TDCSS) micelles were efficiently internalized into HeLa cells, releasing DOX into the cytoplasm after which the drug finally entered the nuclei, while MTT assays also demonstrated potent cytotoxic activity against HeLa cells. DOX was mainly located in the cytoplasm for reduction-insensitive PEG-P(TMC-co-TDCCC) and PEG-PTMC controls.

  16. One-pot synthesis of crosslinked amphiphilic polycarbonates as stable but reduction-sensitive carriers for doxorubicin delivery.

    PubMed

    Yi, Xiaoqing; Zhang, Quan; Dong, Hui; Zhao, Dan; Xu, Jia-qi; Zhuo, Renxi; Li, Feng

    2015-10-01

    In this paper, we first synthesized a novel disulfide-coupled bis-(cyclic carbonate) (TDCSS) monomer. After ring-opening co-polymerization (ROP) of TDCSS and trimethylene carbonate (TMC) initiated by mono-methoxyl poly(ethylene glycol), the crosslinked reduction-sensitive copolymer PEG-P(TMC-co-TDCSS) was obtained via a facile one-step procedure for efficient delivery of doxorubicin (DOX) into cancer cells. To serve as controls, PEG-P(TMC-co-TDCCC), which has an analogous structure without disulfide bond, and a linear polymer PEG-PTMC were also prepared. The copolymers could self-assemble to form nano-sized micelles in an aqueous solution. As compared to PEG-PTMC, crosslinked PEG-P(TMC-co-TDCSS) and PEG-P(TMC-co-TDCCC) showed lower CMC values and thus induced a much better micelle-forming ability. In vitro release studies revealed that the drug release behavior of DOX-loaded PEG-P(TMC-co-TDCSS) micelles, which could be accelerated in the presence of 10 mM dithiothreitol (DTT), showed a similar trend in the absence of DTT compared to DOX-loaded PEG-P(TMC-co-TDCCC) micelles. Furthermore, confocal laser scanning microscopy (CLSM) indicated that DOX-loaded PEG-P(TMC-co-TDCSS) micelles were efficiently internalized into HeLa cells, releasing DOX into the cytoplasm after which the drug finally entered the nuclei, while MTT assays also demonstrated potent cytotoxic activity against HeLa cells. DOX was mainly located in the cytoplasm for reduction-insensitive PEG-P(TMC-co-TDCCC) and PEG-PTMC controls. PMID:26357961

  17. One-pot synthesis of porous Fe3O4 shell/silver core nanocomposites used as recyclable magnetic antibacterial agents

    NASA Astrophysics Data System (ADS)

    Fang, Weijun; Zheng, Jun; Chen, Cheng; Zhang, Huabing; Lu, Yunxia; Ma, Ling; Chen, Guangjun

    2014-05-01

    Porous Fe3O4 shell/silver core nanocomposites featuring sustainable and recyclable antibacterial activity have been successfully prepared via a facile one-pot hydrothermal method. The unique structural feature of the Ag@Fe3O4 nanocomposites with Ag embedded in porous Fe3O4 shell endows them with the ability of sustained-release of silver ions. Their antimicrobial activity studies were investigated on both Gram negative Escherichia coli and Gram positive Bacillus subtilis, which demonstrate that the nanocomposites are highly toxic to microorganisms and exhibit sustainable antibacterial activity. Besides, the Ag@Fe3O4 nanocomposites can be separated easily from the medium by a small magnet, which provided an effective way to eliminate the residual nanosilver from the surroundings. We finally demonstrate that the recovered nanocomposites exhibit recyclable antibacterial activity, acting as an ideal long-acting antibacterial agent.

  18. A facile one-pot reduction method for the preparation of a SnO/SnO2/GNS composite for high performance lithium ion batteries.

    PubMed

    Chen, Xiao-Ting; Wang, Kai-Xue; Zhai, Yu-Bo; Zhang, Hao-Jie; Wu, Xue-Yan; Wei, Xiao; Chen, Jie-Sheng

    2014-02-28

    A SnO/SnO2/GNS composite with controlled oxidation states and composition has been prepared through simple one-pot reduction of an EG suspension of SnCl2 and graphene oxide. The as-prepared composite was characterized by XRD, FT-IR, XPS, SEM, TEM and BET. SnO and SnO2 nanoparticles are uniformly distributed on the surface of the graphene. Taking advantage of the high electron conductivity of graphene and the large theoretical capacity of SnO, this SnO/SnO2/GNS composite exhibits high charge/discharge capacity, good cycling stability and good rate capability. A specific discharge capacity of approximately 464.2 mA h g(-1) is retained after being charged/discharged at a current density of 1000 mA g(-1) for 30 cycles. PMID:24316886

  19. One-pot synthesis of silicon nanoparticles trapped in ordered mesoporous carbon for use as an anode material in lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Park, Junsu; Kim, Gil-Pyo; Nam, Inho; Park, Soomin; Yi, Jongheop

    2013-01-01

    Silicon nanoparticles trapped in an ordered mesoporous carbon composite were prepared by a one-step self-assembly with solvent evaporation using the triblock copolymer Pluronic F127 and a resorcinol-formaldehyde polymer as the templating agent and carbon precursor respectively. Such a one-pot synthesis of Si/ordered mesoporous carbon nanocomposite is suitable for large-scale synthesis. Characterization confirmed that the Si nanoparticles were trapped in the ordered mesoporous carbon, as evidenced by transmission electron microscopy, x-ray diffraction analysis and nitrogen sorption isotherms. The composite showed a high reversible capacity above 700 mA h g-1 during 50 cycles at 2 A g-1. The improved electrochemical performance of the composite can be ascribed to the buffering effect of spaces formed in the ordered pore channels during the volume expansion of silicon and the rapid movement of lithium ions through the uniform cylindrical pore structure of the mesopores.

  20. A novel one-pot and one-step microwave-assisted cyclization-methylation reaction of amino alcohols and acetylated derivatives with dimethyl carbonate and TBAC.

    PubMed

    Ochoa-Terán, Adrián; Guerrero, Leticia; Rivero, Ignacio A

    2014-01-01

    A simple and efficient microwave-assisted methodology for the synthesis of 4-substituted-3-methyl-1,3-oxazolidin-2-ones from amino alcohols catalyzed by a ionic liquid was developed. This novel one-pot and one-step cyclization-methylation reaction represents an easier and faster method than any other reported protocols that can be used to obtain the desired products in good yields and high purity. Applying microwave irradiation at 130°C in the presence of TBAC, dimethyl carbonate acts simultaneously as carbonylating and methylating agent and surprisingly promotes an in situ basic trans esterification when a N-acetylated amino alcohol is used as starting material. Furthermore, dimethyl carbonate worked better than diethyl carbonate in performing this reaction. PMID:25692177

  1. A one-pot sequence for the efficient synthesis of highly functionalized macrocarbocycles or bridged 2,8-dioxabicyclo[3.2.1]octanes from 1-nitrobicyclic compounds.

    PubMed

    Giorgi, Giorgio; López-Alvarado, Pilar; Menéndez, J Carlos

    2012-07-14

    The reaction of 1-nitrobicyclo[n.3.1]alkane-(6 + n)ones with sodium borohydride followed by acidic workup led to ring opening via a one-pot sequence comprising the retro-Dieckmann-type opening of the α-nitroketone structural fragment, followed by aldehyde reduction and a final Nef reaction, leading to highly functionalized 12 to 14-membered carbocyclic ketones bearing three stereocenters, which are adjacent in some of the compounds. The reactions starting from 1-nitrobicyclo[9.3.1]pentadecan-15-ones could be adjusted to give macrocyclic 2,8-dioxabicyclo[3.2.1]octanes containing an additional bridge by diastereoselective formation of a third ring and a fourth stereocenter through acid-promoted intramolecular ketal formation. This is a very interesting ring system related to the core of the zaragozic acid family of natural products. PMID:22641240

  2. Efficient one-pot synthesis of CXCL14 and its derivative using an N-sulfanylethylanilide peptide as a peptide thioester equivalent and their biological evaluation.

    PubMed

    Tsuji, Kohei; Tanegashima, Kosuke; Sato, Kohei; Sakamoto, Ken; Shigenaga, Akira; Inokuma, Tsubasa; Hara, Takahiko; Otaka, Akira

    2015-09-01

    CXCL14 is a CXC-type chemokine that exhibits chemotactic activity for immature dendritic cells, activated macrophages, and activated natural killer cells. However, its specific receptor and signaling pathway remain obscure. Recently, it was reported that CXCL14 binds to CXCR4 with high affinity and inhibits CXCL12-mediated chemotaxis. Furthermore, the CXCL14 C-terminal α-helical region is important for binding to its receptor. In this context, we chemically synthesized CXCL14 and its derivative with a one-pot method using N-sulfanylethylanilide peptide as a thioester equivalent. The synthetic CXCL14 proteins possessed inhibitory activities to CXCL12-mediated chemotaxis comparable with that of recombinant CXCL14. Moreover, we proved that chemically biotinylated CXCL14 binds to CXCR4 on cells by flow cytometry analysis. PMID:26187016

  3. An efficient one pot syntheses of aryl-3,3'-bis(indolyl)methanes and studies on their spectral characteristics, DPPH radical scavenging-, antimicrobial-, cytotoxicity-, and antituberculosis activity

    NASA Astrophysics Data System (ADS)

    Suresh Kumar, G. S.; Kumaresan, S.; Antony Muthu Prabhu, A.; Bhuvanesh, N.; Seethalakshmi, P. G.

    2013-01-01

    An efficient one-pot syntheses of aryl-3,3'-bis(indolyl)methanes (BIMs) from indole/2-methylindole and formylphenoxyaliphatic acid(s) is described. Esterification of carboxylic acid and aromatic electrophilic substitution reactions are achieved simultaneous in the presence of potash alum as a catalyst. This catalyst could be recovered and reused without substantial loss in its catalytic activity and the methodology could be applied on a range of closely related substrates. The solvation characteristics in ground and excited states of the compounds by monitoring the absorbance and fluorescence band maxima have been studied. The fluorescence studies in protic and aprotic solvents were rationalized on the basis of solute-solvent interaction and substituents effect on these photophysical processes analyzed. The compounds prepared showed efficient antimicrobial effect against human pathogens, cytotoxicity against A431 cell line, and DPPH radical scavenging effect. Single crystal XRD studies have been carried out for a few compounds synthesized in this work.

  4. A Novel One-Pot and One-Step Microwave-Assisted Cyclization-Methylation Reaction of Amino Alcohols and Acetylated Derivatives with Dimethyl Carbonate and TBAC

    PubMed Central

    Ochoa-Terán, Adrián; Guerrero, Leticia; Rivero, Ignacio A.

    2014-01-01

    A simple and efficient microwave-assisted methodology for the synthesis of 4-substituted-3-methyl-1,3-oxazolidin-2-ones from amino alcohols catalyzed by a ionic liquid was developed. This novel one-pot and one-step cyclization-methylation reaction represents an easier and faster method than any other reported protocols that can be used to obtain the desired products in good yields and high purity. Applying microwave irradiation at 130°C in the presence of TBAC, dimethyl carbonate acts simultaneously as carbonylating and methylating agent and surprisingly promotes an in situ basic trans esterification when a N-acetylated amino alcohol is used as starting material. Furthermore, dimethyl carbonate worked better than diethyl carbonate in performing this reaction. PMID:25692177

  5. Enhanced oxidation-resistant Cu-Ni core-shell nanowires: controllable one-pot synthesis and solution processing to transparent flexible heaters

    NASA Astrophysics Data System (ADS)

    Chen, Jianyu; Chen, Jun; Li, Yi; Zhou, Weixin; Feng, Xiaomiao; Huang, Qingli; Zheng, Jian-Guo; Liu, Ruiqing; Ma, Yanwen; Huang, Wei

    2015-10-01

    Coating nickel onto copper nanowires (Cu NWs) by one-pot synthesis is an efficient approach to improving the oxidation resistance of the nanowires. Because Ni is much less conductive than Cu, it is of great importance to understand the relationship between the thickness of the Ni coating layer and the properties of NWs. Here we demonstrate one-pot synthesis of Cu-Ni core-shell NWs with a tunable Ni thickness by simply varying the Cu and Ni mole ratio in the precursor. We have observed that an increase in Ni thickness decreases the aspect ratio, surface smoothness and network conductivity of the resulting NWs. However, Cu-Ni NWs with a thicker Ni layer display higher oxidation temperature. The optimal Cu-Ni NWs, which were prepared using a Cu2+/Ni2+ molar ratio of 1/1, have a Ni-layer thickness of about 10 nm and the onset oxidation temperature of 270 °C. The derived transparent conductive films present a transmittance of 76% and a sheet resistance of 300 Ω sq-1. The flexible heater constructed from such high quality Cu-Ni NW films demonstrates effective performance in heating and defrosting.Coating nickel onto copper nanowires (Cu NWs) by one-pot synthesis is an efficient approach to improving the oxidation resistance of the nanowires. Because Ni is much less conductive than Cu, it is of great importance to understand the relationship between the thickness of the Ni coating layer and the properties of NWs. Here we demonstrate one-pot synthesis of Cu-Ni core-shell NWs with a tunable Ni thickness by simply varying the Cu and Ni mole ratio in the precursor. We have observed that an increase in Ni thickness decreases the aspect ratio, surface smoothness and network conductivity of the resulting NWs. However, Cu-Ni NWs with a thicker Ni layer display higher oxidation temperature. The optimal Cu-Ni NWs, which were prepared using a Cu2+/Ni2+ molar ratio of 1/1, have a Ni-layer thickness of about 10 nm and the onset oxidation temperature of 270 °C. The derived

  6. Scaffold Diversity through a Branching Double-Annulation Cascade Strategy: Iminium-Induced One-Pot Synthesis of Diverse Fused Tetrahydroisoquinoline Scaffolds.

    PubMed

    Sharada, Duddu S; Shinde, Anand H; Patel, Srilaxmi M; Vidyacharan, Shinde

    2016-08-01

    A branching double-annulation cascade (BDAC) strategy for diverse and complex fused THIQ scaffolds via a highly reactive iminium-induced one-pot double-cyclization sequence involving Pictect-Spengler-type cyclization has been developed for the first time. The salient features of this protocol are that it allows direct and rapid access to unprecedented diverse fused THIQ skeletons, is metal/catalyst free, has a cleaner reaction profile, provides good to excellent yields, and is a convenient approach. This catalyst-free domino process facilitates the double annulation with a variety of scaffold building agents via two C-N and one C-X (X = C, N, O) bond formation in a single step under uniform reaction conditions. Furthermore, we reveal an unusual dual BDAC sequence leading to N-N-linked isoquinoline dimer. PMID:27399888

  7. β-Cyclodextrin-Propyl Sulfonic Acid Catalysed One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles as Local Anesthetic Agents.

    PubMed

    Ran, Yan; Li, Ming; Zhang, Zong-Ze

    2015-01-01

    Some functionalized 1,2,4,5-tetrasubstituted imidazole derivatives were synthesized using a one-pot, four component reaction involving 1,2-diketones, aryl aldehydes, ammonium acetate and substituted aromatic amines. The synthesis has been efficiently carried out in a solvent free medium using β-cyclodextrin-propyl sulfonic acid as a catalyst to afford the target compounds in excellent yields. The local anesthetic effect of these derivatives was assessed in comparison to lidocaine as a standard using a rabbit corneal and mouse tail anesthesia model. The three most potent promising compounds were subjected to a rat sciatic nerve block assay where they showed considerable local anesthetic activity, along with minimal toxicity. Among the tested analogues, 4-(1-benzyl-4,5-diphenyl-1H-imidazol-2-yl)-N,N-dimethylaniline (5g) was identified as most potent analogue with minimal toxicity. It was further characterized by a more favourable therapeutic index than the standard. PMID:26569210

  8. Unsaturated C3,5,7,9-Monocarboxylic Acids by Aqueous, One-Pot Carbon Fixation: Possible Relevance for the Origin of Life

    PubMed Central

    Scheidler, Christopher; Sobotta, Jessica; Eisenreich, Wolfgang; Wächtershäuser, Günter; Huber, Claudia

    2016-01-01

    All scientific approaches to the origin of life share a common problem: a chemical path to lipids as main constituents of extant cellular enclosures. Here we show by isotope-controlled experiments that unsaturated C3,5,7,9-monocarboxylic acids form by one-pot reaction of acetylene (C2H2) and carbon monoxide (CO) in contact with nickel sulfide (NiS) in hot aqueous medium. The primary products are toto-olefinic monocarboxylic acids with CO-derived COOH groups undergoing subsequent stepwise hydrogenation with CO as reductant. In the resulting unsaturated monocarboxylic acids the double bonds are mainly centrally located with mainly trans-configuration. The reaction conditions are compatible with an origin of life in volcanic-hydrothermal sub-seafloor flow ducts. PMID:27283227

  9. 3,4,5-Trisubstituted Furan-2(5H)-one Derivatives: Efficient one-pot Synthesis and Evaluation of Cytotoxic Activity.

    PubMed

    Basyouni, W M; El-Bayouki, Kh A M; El-Sayed, A S; Tohamy, W M; Farag, M M S; Abd-El-Baseer, M A

    2015-09-01

    A series of 3,4,5-trisubstituted 2(5H)-furanone derivatives was synthesized through one-pot reaction of amines, aldehydes and diethyl acetylenedicarboxylate. Silica sulfuric acid efficiently catalyzes the 3-component reaction to afford the corresponding 2(5H)-furanones in high yields. The synthesized compounds were tested against HEPG2, MCF7 and CACO tumor cell lines. The cytotoxic activity for the tested compounds showed that: ethyl 2-(4-fluorophenyl)-5-oxo-4-(phenylamino)-2,5-dihydrofuran-3-carboxylate exhibited significant antitumor activity against HEPG2 and MCF7 cell lines (IC50 values 0.002 and 0.002 µM, respectively) more than reference drug (IC50 0.007, 0.005 µM). PMID:25207706

  10. A one-pot and in situ synthesis of CuS-graphene nanosheet composites with enhanced peroxidase-like catalytic activity.

    PubMed

    Nie, Guangdi; Zhang, Liang; Lu, Xiaofeng; Bian, Xiujie; Sun, Weining; Wang, Ce

    2013-10-14

    CuS-graphene nanosheet (GNS) composites with well-defined morphology have been successfully fabricated via a simple one-pot hydrothermal route by using thioacetamide (TAA) as both the sulfur source and reducing agent. The as-prepared CuS-GNS composites with an appropriate content of graphene exhibited an even higher peroxidase-like catalytic activity than pristine CuS nanoparticles in acetate buffer solution (pH = 4.0), which provided a facile method for the colorimetric detection of hydrogen peroxide (H2O2). It was calculated that H2O2 could be detected as low as 1.2 μM (S/N = 3) with a wide linear range from 2.0 to 20.0 μM (R(2) = 0.992), indicating that the as-prepared catalyst as an artificial peroxidase is promising for application in biosensors and environmental monitoring. PMID:23933916

  11. One-Pot Template-Free Synthesis of Cu-MOR Zeolite toward Efficient Catalyst Support for Aerobic Oxidation of 5-Hydroxymethylfurfural under Ambient Pressure.

    PubMed

    Zhang, Wei; Xie, Jingyan; Hou, Wei; Liu, Yangqing; Zhou, Yu; Wang, Jun

    2016-09-01

    Supported catalysts are widely studied, and exploring new promising supports is significant to access more applications. In this work, novel copper-containing MOR-type zeolites Cu-MOR were synthesized in a one-pot template-free route and served as efficient supports for vanadium oxide. In the heterogeneous oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) with molecular oxygen (O2) under ambient pressure, the obtained catalyst demonstrated high yield (91.5%) and good reusability. Even under the ambient air pressure, it gave a DFF yield of 72.1%. Structure-activity relationship analysis indicated that the strong interaction between the framework Cu species and the guest V sites accounted for the remarkable performance. This work reveals that the Cu-MOR zeolite uniquely acts as the robust support toward well-performed non-noble metal heterogeneous catalyst for biomass conversion. PMID:27523255

  12. An efficient one-pot two catalyst system in the construction of 2-substituted benzimidazoles: synthesis of benzimidazo[1,2-c]quinazolines.

    PubMed

    Cimarelli, Cristina; Di Nicola, Matteo; Diomedi, Simone; Giovannini, Riccardo; Hamprecht, Dieter; Properzi, Roberta; Sorana, Federico; Marcantoni, Enrico

    2015-12-28

    The benzimidazole core is a common moiety in a large number of natural products and pharmacologically active small molecules. The synthesis of novel benzimidazole derivatives remains a main focus in medicinal research. In continuation of the efforts towards Ce(III) catalysts for organic transformations, we observed for the first time the activity of the iodide ion and copper cation in activating CeCl3·7H2O in the selective formation of prototypical 2-substituted benzimidazoles. The one-pot CeCl3·7H2O-CuI catalytic system procedure includes the cyclo-dehydrogenation of aniline Schiff's bases, generated in situ from the condensation of 1,2-phenylenediamine and aldehydes, followed by the oxidation with iodine, which works as a hydrogen sponge. Mild reaction conditions, good to excellent yields, and clean reactions make the procedure a useful contribution to the synthesis of biologically active fused heterocycles containing benzimidazoquinazolines. PMID:26477673

  13. Direct hydrogenation and one-pot reductive amidation of nitro compounds over Pd/ZnO nanoparticles as a recyclable and heterogeneous catalyst

    NASA Astrophysics Data System (ADS)

    Hosseini-Sarvari, Mona; Razmi, Zahra

    2015-01-01

    A novel Pd supported on ZnO nanoparticles was readily synthesized and characterized. The amount of palladium on ZnO is 9.84 wt% which was determined by ICP analysis and atomic absorption spectroscopy (AAS). Percentage of accessible Pd as active catalyst is also estimated to 2.72% based on the thermogravimetric (TG) analysis. This nano-sized Pd/ZnO with an average particle size of 20-25 nm and specific surface area 40.61 m2 g-1 was used as a new reusable heterogeneous catalyst for direct hydrogenation and one-pot reductive amidation of nitro compounds without the use of any ligands under atmospheric pressure. The catalyst can be recovered and recycled several times without marked loss of activity.

  14. Ionic liquids as unique solvents in one-pot synthesis of 4-(n,2,2,2-tetranitroethylamino)-3-R-furazans.

    PubMed

    Sheremetev, Aleksei B; Aleksandrova, Nataly S; Palysaeva, Nadezhda V; Struchkova, Marina I; Tartakovsky, Vladimir A; Suponitsky, Kyrill Yu

    2013-09-01

    An efficient two-step one-pot protocol for the synthesis of N-nitrated trinitroethylamino furazans in an ionic liquid has been developed involving the condensation of aminofurazans with trinitroethanol and the N-nitration of an intermediate Mannich base. Trinitroethylnitramino derivatives have been synthesized and characterized by multinuclear NMR spectroscopy and X-ray crystallography. A role of the N,2,2,2-tetranitroethylamino group for stabilization of the high-density crystal-packing motif is described. The performance calculations gave detonation pressures and velocities for the furazan derivatives in a range of about 31-36 GPa and 8330-8745 ms(-1), respectively, which makes them competitive energetic materials. Furthermore, due to the positive oxygen balance, the compounds could be potential oxidizers for energetic formulations. PMID:23897761

  15. One-pot synthesis of NiFe layered double hydroxide/reduced graphene oxide composite as an efficient electrocatalyst for electrochemical and photoelectrochemical water oxidation

    NASA Astrophysics Data System (ADS)

    Youn, Duck Hyun; Park, Yoon Bin; Kim, Jae Young; Magesh, Ganesan; Jang, Youn Jeong; Lee, Jae Sung

    2015-10-01

    As an efficient non-precious metal catalyst for oxygen evolution reaction (OER) in electrochemical and photoelectrochemical water splitting, NiFe layered double hydroxide (LDH)/reduced graphene oxide (NiFe/RGO) composite is synthesized by a simple solvothermal method in one-pot. NiFe LDHs are uniformly deposited on RGO layers of high electrical conductivity and large surface area. In electrochemical water splitting, NiFe/RGO shows superior OER performance compared to bare NiFe and reference IrO2 with a lower benchmark η10 value (required overpotential to drive 10 mA cm-2) of 0.245 V. Furthermore, NiFe/RGO substantially increases the performance of a hematite photoanode in photoelectrochemical water oxidation, demonstrating its potential as an OER co-catalyst for photoelectrodes.

  16. One-pot synthesis, structural characterization, UV-Vis and electrochemical analyses of new Schiff base complexes of Fe(III), Ni(II) and Cu(II)

    NASA Astrophysics Data System (ADS)

    Back, Davi Fernando; de Oliveira, Gelson Manzoni; Fontana, Liniquer Andre; Ramão, Brenda Fiorin; Roman, Daiane; Iglesias, Bernardo Almeida

    2015-11-01

    The complexes [Ni(Pyr2tetam-2H)]·2H2O (1) (Pyr2tetam = (pyridoxyl)2-N1,N4-triethylenetetramine), [Fe(Pyr2tetam-2H)](ClO4)·H2O (2) and [Cu(Pyrtetam-H)](ClO4) (3) (Pyrtetam = pyridoxyl-N1-triethylenetetramine) were obtained through one pot reactions of triethylenetetramine, pyridoxal chloridrate, triethylamine and the metal salts Ni(ClO4)2·6H2O, Fe(ClO4)2·6H2O and Cu(ClO4)2·6H2O. In complexes 1 and 2 the metal centers present a distorted octahedral coordination, while complex 3 shows a square pyramidal configuration. The structures were characterized through X-ray diffractometry, IR and UV-Vis spectra. Cyclic voltammograms of the title compounds are also presented and discussed.

  17. Unsaturated C3,5,7,9-Monocarboxylic Acids by Aqueous, One-Pot Carbon Fixation: Possible Relevance for the Origin of Life.

    PubMed

    Scheidler, Christopher; Sobotta, Jessica; Eisenreich, Wolfgang; Wächtershäuser, Günter; Huber, Claudia

    2016-01-01

    All scientific approaches to the origin of life share a common problem: a chemical path to lipids as main constituents of extant cellular enclosures. Here we show by isotope-controlled experiments that unsaturated C3,5,7,9-monocarboxylic acids form by one-pot reaction of acetylene (C2H2) and carbon monoxide (CO) in contact with nickel sulfide (NiS) in hot aqueous medium. The primary products are toto-olefinic monocarboxylic acids with CO-derived COOH groups undergoing subsequent stepwise hydrogenation with CO as reductant. In the resulting unsaturated monocarboxylic acids the double bonds are mainly centrally located with mainly trans-configuration. The reaction conditions are compatible with an origin of life in volcanic-hydrothermal sub-seafloor flow ducts. PMID:27283227

  18. Accessing a Biologically Relevant Benzofuran Skeleton by a One-Pot Tandem Heck Alkynylation/Cyclization Reaction Using Well-Defined Palladium N-Heterocyclic Carbene Complexes.

    PubMed

    Kumar, Anuj; Gangwar, Manoj Kumar; Prakasham, A P; Mhatre, Darshan; Kalita, Alok Ch; Ghosh, Prasenjit

    2016-03-21

    Well-defined palladium N-heterocyclic carbene (NHC) complexes were employed in the one-pot tandem Heck alkynylation/cyclization sequence for preparing biologically relevant benzofuran compounds under copper-free conditions in a time-efficient step-reduced fashion. In particular, a series of binuclear palladium complexes, 1b-1e and 2b-2e, of the alkyl-bridged NHC ligands, namely, {1,1'-di-R1-4,4'-R2-di-1,2,4-triazoline-5,5'-diylid-2-ene] (R1 = i-Pr; R2 = -(CH2)2-, -(CH2)3-), and their mononuclear analogues, trans-(NHC)PdBr2(pyridine) (3b) and cis-(NHC)PdBr2(PPh3) (3c), successfully catalyzed the one-pot tandem Heck alkynylation/cyclization reaction of 2-iodophenol with a variety of terminal alkyne substrates, yielding 2-substituted benzofuran derivatives. The mononuclear complexes 3b and 3c were nearly half as active as the representative dinuclear analogue 1c under analogous reaction conditions, thereby implying that, at the same mole percent of the palladium loading, the monometallic 3b and 3c and the bimetallic 1c complexes were equally effective as catalysts. The two sites of the bimetallic complex 1c performed as two separate independent catalytic sites, displaying no cooperativity effect in the catalysis. Finally, the practical utility of the aforementioned catalysts was demonstrated for a representative catalyst 1c through the convenient synthesis of a key intermediate, 3-[2-(benzo[d][1,3]dioxol-5-yl)-7-methoxybenzofuran-5-yl]propan-1-ol, in a total-synthesis protocol of the natural product Egonol. PMID:26928799

  19. Amplification and modulation of fluorescent signals by using hybridization chain reactions for multiplexed sensing of biomolecules in a one-pot

    NASA Astrophysics Data System (ADS)

    Nishimura, Takahiro; Ogura, Yusuke; Yamada, Kenji; Ohno, Yuko; Tanida, Jun

    2014-02-01

    Fluorescence readout of molecular information is a promising approach for biomolecular sensing. For detection of enormous biomolecules via uorescence, biomolecular information should be converted to codes that can be readout easily and simultaneously. For the purpose, we study a biomolecule uorescence color (B/F) encoders that modulate uorescence signals by control of uorescence resonance energy transfer (FRET). The B/F encoder converts biomolecular signals into uorescent color codes represented with uorescent wavelengths and intensity levels. The combination offers a great number of codes for representing the biomolecular information. In this study, we discuss multiplexed detection of target biomolecules using B/F encoders. Use of the B/F encoders would offer a multiplexed biomolecular sensing in a one-pot without micro-fabrication like DNA microarray. In the experiments, we prepared B/F encoders based on two kinds of hybridization chain reactions (HCR) that make long double-stranded DNA polymers to control positions of uorescence and quencher molecules. In the B/F encoders, target molecules trigger to start assembling the polymer structures. The uorescent molecules in the absence of the targets are near the quenchers and the output uorescence is suppressed by FRET. The polymerization process separates the uorescent and quencher dyes and the uorescent signal increase. The experimental results show that the B/F encoders based on HCRs have linear and independent response to each target, and temporal signals during the encoding reactions are usable for multiplexed readout. This result leads to the multiplexed sensing in a one-pot by uorescent ampli cation and multiple uorescent color-coding.

  20. Rapid 'one-pot' synthesis of a novel benzimidazole-5-carboxylate and its hydrazone derivatives as potential anti-inflammatory and antimicrobial agents.

    PubMed

    Vasantha, Kumar; Basavarajaswamy, Guru; Vaishali Rai, M; Boja, Poojary; Pai, Vinitha R; Shruthi, N; Bhat, Mahima

    2015-04-01

    A novel series of N-arylidene-2-(2,4-dichloro phenyl)-1-propyl-1H-benzo[d] imidazole-5-carbohydrazides having different substitution on the arylidene part were synthesized in good yield. The core nucleus benzimidazole-5-carboxylate (5) was efficiently synthesized by 'one-pot' nitro reductive cyclization reaction between ethyl-3-nitro-4-(propylamino)benzoate and 2,4-dichlorobenzaldehyde using sodium dithionite in dimethylsulfoxide. This 'one-pot' reaction was proceeded very smoothly, in short reaction time with an excellent yield. All the compounds (7a-r) were screened for their in vivo anti-inflammatory and in vitro antimicrobial activity. Most of the compounds exhibited remarkable paw-edema inhibition in the initial one hour of administration indicating the higher potentiality of these molecules. In particular, compounds 7a, 7d, 7f and 7g displayed a high level of carrageenan-induced paw edema inhibition compared to that of indomethacin. Compound 7p exhibited very good antibacterial activity and antifungal activity with a MIC of 3.12 μg/mL against most of the tested organisms. Furthermore, compounds 7d, 7f, 7h and 7p found to be good inhibitors of Aspergillus niger with MIC of 3.12 μg/mL. Cytotoxicity of the potent compounds 7d, 7f and 7p was checked using MDA MB-231 breast cancer cell line and are found to be non toxic at the highest concentration used (i.e., 10 μg/mL). PMID:25765910

  1. One-pot solvothermal synthesis of ZnFe{sub 2}O{sub 4} nanospheres/graphene composites with improved lithium-storage performance

    SciTech Connect

    Shi, Jingjing; Zhou, Xiaoyan; Liu, Ya; Su, Qingmei; Zhang, Jun; Du, Gaohui

    2015-05-15

    Highlights: • A one-pot solvothermal route is developed for synthesizing ZnFe{sub 2}O{sub 4}/graphene nanocomposites. • ZnFe{sub 2}O{sub 4} nanospheres with a size of about 100–200 nm are uniformly dispersed on graphene nanosheets. • The nanocomposite delivers a reversible capacity of 704 mAh/g after 50 cycles. • The improved lithium-storage performance is ascribed to the confining and conducting effects of graphene nanosheets. - Abstract: We report a facile one-pot solvothermal route for synthesizing ZnFe{sub 2}O{sub 4}/graphene nanocomposites. XRD, SEM and TEM results demonstrate that ZnFe{sub 2}O{sub 4} nanospheres with a size of about 100–200 nm are uniformly dispersed on graphene nanosheets. Each ZnFe{sub 2}O{sub 4} nanosphere is assembled by many nanoparticles around 10 nm. When evaluated as anode for Li-ion batteries, ZnFe{sub 2}O{sub 4}/graphene nanocomposites deliver a first discharge capacity of 1400 mAh g{sup −1} and remain a reversible capacity up to 704.2 mAh g{sup −1} after 50 cycles. ZnFe{sub 2}O{sub 4}/graphene nanocomposites also exhibit ameliorative rate capacity of 271.8 mAh g{sup −1} at the current of 800 mA g{sup −1}, which can recover to 814 mAh g{sup −1} when the current density is reduced back to 100 mA g{sup −1}. The enhanced electrochemical performances of the nanocomposites are ascribed to the confining and conducting effects of graphene and the synergistic effects between the conductive graphene and ZnFe{sub 2}O{sub 4} nanospheres.

  2. One-Pot Synthesis of Fe(III)-Polydopamine Complex Nanospheres: Morphological Evolution, Mechanism, and Application of the Carbonized Hybrid Nanospheres in Catalysis and Zn-Air Battery.

    PubMed

    Ang, Jia Ming; Du, Yonghua; Tay, Boon Ying; Zhao, Chenyang; Kong, Junhua; Stubbs, Ludger Paul; Lu, Xuehong

    2016-09-13

    We report one-pot synthesis of Fe(III)-polydopamine (PDA) complex nanospheres, their structures, morphology evolution, and underlying mechanism. The complex nanospheres were synthesized by introducing ferric ions into the reaction mixture used for polymerization of dopamine. It is verified that both the oxidative polymerization of dopamine and Fe(III)-PDA complexation contribute to the "polymerization" process, in which the ferric ions form coordination bonds with both oxygen and nitrogen, as indicated by X-ray absorption fine-structure spectroscopy. In the "polymerization" process, the morphology of the complex nanostructures is gradually transformed from sheetlike to spherical at the feed Fe(III)/dopamine molar ratio of 1/3. The final size of the complex spheres is much smaller than its neat PDA counterpart. At higher feed Fe(III)/dopamine molar ratios, the final morphology of the "polymerization" products is sheetlike. The results suggest that the formation of spherical morphology is likely to be driven by covalent polymerization-induced decrease of hydrophilic functional groups, which causes reself-assembly of the PDA oligomers to reduce surface area. We also demonstrate that this one-pot synthesis route for hybrid nanospheres enables the facile construction of carbonized PDA (C-PDA) nanospheres uniformly embedded with Fe3O4 nanoparticles of only 3-5 nm in size. The C-PDA/Fe3O4 nanospheres exhibit catalytic activity toward oxygen reduction reaction and deliver a stable discharge voltage for over 200 h when utilized as the cathode in a primary Zn-air battery and are also good recyclable catalyst supports. PMID:27550631

  3. A Fully-automated One-pot Synthesis of [18F]Fluoromethylcholine with Reduced Dimethylaminoethanol Contamination via [18F]Fluoromethyl Tosylate

    PubMed Central

    Rodnick, Melissa E.; Brooks, Allen F.; Hockley, Brian G.; Henderson, Bradford D.; Scott, Peter J. H.

    2013-01-01

    Introduction A novel one-pot method for preparing [18F]fluoromethylcholine ([18F]FCH) via in situ generation of [18F]fluoromethyl tosylate ([18F]FCH2OTs), and subsequent [18F]fluoromethylation of dimethylaminoethanol (DMAE), has been developed. Methods [18F]FCH was prepared using a GE TRACERlab FXFN, although the method should be readily adaptable to any other fluorine-18 synthesis module. Initially ditosylmethane was fluorinated to generate [18F]FCH2OTs. DMAE was then added and the reaction was heated at 120°C for 10 min to generate [18F]FCH. After this time, reaction solvent was evaporated, and the crude reaction mixture was purified by solid-phase extraction using C18-Plus and CM-Light Sep-Pak cartridges to provide [18F]FCH formulated in USP saline. The formulated product was passed through a 0.22 μm filter into a sterile dose vial, and submitted for quality control testing. Total synthesis time was 1.25 hours from end-of-bombardment. Results Typical non-decay-corrected yields of [18F]FCH prepared using this method were 91 mCi (7% non-decay corrected based upon ~1.3 Ci [18F]fluoride), and doses passed all other quality control (QC) tests. Conclusion A one-pot liquid-phase synthesis of [18F]FCH has been developed. Doses contain extremely low levels of residual DMAE (31.6 μg / 10 mL dose or ~3 ppm) and passed all other requisite QC testing, confirming their suitability for use in clinical imaging studies. PMID:23665261

  4. A one-pot catalyst-free synthesis of functionalized pyrrolo[1,2-a]quinoxaline derivatives from benzene-1,2-diamine, acetylenedicarboxylates and ethyl bromopyruvate.

    PubMed

    Piltan, Mohammad; Moradi, Loghman; Abasi, Golaleh; Zarei, Seyed Amir

    2013-01-01

    The catalyst-free multicomponent reaction of 1,2-diaminobenzene, dialkyl acetylenedicarboxylates, and ethyl bromopyruvate forms pyrrolo[1,2-a]quinoxaline derivatives in good yields. Ethylenediamine also reacts under similar conditions to produce new pyrrolo[1,2-a]pyrazine derivatives. PMID:23616791

  5. Enhanced optical properties of heterostructured ZnO/CeO2 nanocomposite fabricated by one-pot hydrothermal method: Fluorescence and ultraviolet absorption and visible light transparency

    NASA Astrophysics Data System (ADS)

    He, Geping; Fan, Huiqing; Wang, Zhiwei

    2014-12-01

    Many researchers investigated the properties of either discrete metal oxide CeO2 or ZnO materials. However, less attention has been paid to the various nanostructure and performances of CeO2 and ZnO nanocomposite up to now. In this paper, a facile and low cost one-pot hydrothermal synthesis method has been adopted to obtained directly precursors of CeCO3OH and Zn5(CO3)2(OH)6 with different Ce atom molar ratios to Zn, which are transformed into their corresponding metal oxide to form the ZnO/CeO2 heterostructure nanocomposites (HSNCs) by pyrolysis. The heterostructure is composed of ZnO and CeO2 monocrystals, simultaneously, CeO2 monocrystals are well dispersed on the surface of ZnO monocrystal for cosmetics. Bing dependent on the analysis results of XRD and TEM for the obtained precursors before and after pyrolysis, the formation mechanism of HSNCs was proposed. To the best of our knowledge, the paper first reported heterostructured ZnO/CeO2 nanocomposite grown in one-pot mixed aqueous solution of cerium nitrate, zinc acetate and urea without other extra surfactant. Additionally, the influence of various Ce/Zn molar ratios on the heterostructure, fluorescence emission and UV-visible absorption properties of HSNCs was investigated in detail. ZnO/CeO2 HSNCs display higher fluorescence emission with the increasing Ce/Zn molar ratio. Meanwhile, the larger Ce/Zn molar ratio of ZnO/CeO2 HSNCs, the stronger transparency in the visible light region and the weaker UV absorption. The results are due to the fact that the band gap of ZnO/CeO2 HSNCs will decrease from 3.25 to 3.08 eV when Ce/Zn atom molar ratio is increased from 0 to 0.08. By the comprehensive analysis on the optical performances of HSNCs with the different Ce/Zn atom molar ratios, ZnO/CeO2-0.04 HSNCs could become UV absorber materials and transparent material in the visible region. ZnO/CeO2-0.04 HSNCs with the UV-filtering and Vis-transparent properties is appropriate for personal-care cosmetics.

  6. One-pot synthesis of Au@Pd core-shell nanocrystals with multiple high- and low-index facets and their high electrocatalytic performance

    NASA Astrophysics Data System (ADS)

    Park, Yangsun; Lee, Young Wook; Kang, Shin Wook; Han, Sang Woo

    2014-07-01

    Bimetallic nanocrystals (NCs) enclosed by high-surface energy facets have been of enormous interest due to their pronounced catalytic performance in numerous chemical and electrochemical reactions. However, it remains a significant challenge to develop a facile method to synthesize bimetallic NCs with high-surface energy facets in the form of finely tuned structures due to the difficulties in manipulating the nucleation and growth kinetics of NCs in the presence of multiple metal precursors. In the present work, a facile one-pot aqueous synthesis method is developed for the production of bimetallic Au@Pd core-shell NCs with an unusual truncated hexoctahedral (THOH) shape without pre-synthesized seeds. The THOH Au@Pd NCs are bound by multiple high- and low-index facets. The formation of this unique structure is realized through co-reduction of Au and Pd precursors under precisely controlled kinetic conditions. The prepared THOH NCs exhibit a prominent electrocatalytic performance for ethanol oxidation, which is attributed to their characteristic structural features. This study significantly expands the understanding of NC growth and will lead to fabricating novel nanomaterials with desired morphologies and functions.Bimetallic nanocrystals (NCs) enclosed by high-surface energy facets have been of enormous interest due to their pronounced catalytic performance in numerous chemical and electrochemical reactions. However, it remains a significant challenge to develop a facile method to synthesize bimetallic NCs with high-surface energy facets in the form of finely tuned structures due to the difficulties in manipulating the nucleation and growth kinetics of NCs in the presence of multiple metal precursors. In the present work, a facile one-pot aqueous synthesis method is developed for the production of bimetallic Au@Pd core-shell NCs with an unusual truncated hexoctahedral (THOH) shape without pre-synthesized seeds. The THOH Au@Pd NCs are bound by multiple high- and

  7. A one-pot, three-step process for the diastereoselective synthesis of aminobicyclo[4.3.0]nonanes using consecutive palladium(II)- and ruthenium(II)-catalysis.

    PubMed

    Mostafa, Mohamed A B; Grafton, Mark W; Wilson, Claire; Sutherland, Andrew

    2016-03-28

    A diastereoselective synthesis of highly substituted aminobicyclo[4.3.0]nonanes has been attained using a one-pot multi-bond forming process. A four-step synthetic route was developed for the efficient synthesis of a series of C-7 substituted hept-2-en-6-yn-1-ols. These compounds were then investigated as substrates for a one-pot, three-step tandem process involving a palladium(ii)-catalysed Overman rearrangement, a ruthenium(ii)-catalysed ring closing enyne metathesis reaction followed by a hydrogen bond directed Diels-Alder reaction. The optimisation of the one-pot process has allowed the rapid preparation of a library of aminobicyclo[4.3.0]nonanes with significant molecular complexity and up to four stereogenic centres. PMID:26932788

  8. Functionalization of cubic mesoporous silica SBA-16 with carboxylic acid via one-pot synthesis route for effective removal of cationic dyes.

    PubMed

    Tsai, Cheng-Hsun; Chang, Wei-Chieh; Saikia, Diganta; Wu, Cheng-En; Kao, Hsien-Ming

    2016-05-15

    In this work, we demonstrate that a high density of −COOH groups loading, up to 60 mol% based on silica, is successfully incorporated into SBA-16 via a one-pot synthesis route, which involves co-condensation of carboxyethylsilanetriol sodium salt (CES) and tetraethylorthosilicate (TEOS) templated by Pluronic F127 and P123 in an acidic medium. A variety of characterization techniques are performed to confirm quantitative incorporation of carboxylic groups into ordered cubic mesostructures. These functionalized materials are used to effectively remove two cationic dyes methylene blue (MB) and phenosafranine (PF) with the maximum adsorption capacities of 561 and 519 mg g(-1), respectively, at pH 9. The zeta potential results reveal that the electrostatic interactions between cationic dye molecule and negatively charged surface of the adsorbent play a crucial role in their high adsorption capacities. For a binary component system consisting of MB and PF, competitive adsorption of these two dyes is observed with adsorption capacity values slightly lower than those of the corresponding single dye systems. The dye adsorbed material can be easily regenerated by simple acid washing and be reused for five times with MB removal efficiency still up to 98.6%, showing its great potentials in environmental remediation. PMID:26906434

  9. Improving the drug delivery characteristics of graphene oxide based polymer nanocomposites through the "one-pot" synthetic approach of single-electron-transfer living radical polymerization

    NASA Astrophysics Data System (ADS)

    Gao, Peng; Liu, Meiying; Tian, Jianwen; Deng, Fengjie; Wang, Ke; Xu, Dazhuang; Liu, Liangji; Zhang, Xiaoyong; Wei, Yen

    2016-08-01

    Graphene oxide (GO) based polymer nanocomposites have attracted extensive research interest recently for their outstanding physicochemical properties and potential applications. However, surface modification of GO with synthetic polymers has demonstrated to be trouble for most polymerization procedures are occurred under non-aqueous solution, which will in turn lead to the restacking of GO. In this work, a facile and efficient "one-pot" strategy has been developed for surface modification of GO with synthetic polymers through single-electron-transfer living radical polymerization (SET-LRP). The GO based polymer nanocomposites were obtained via SET-LRP in aqueous solution using poly(ethylene glycol) methyl ether methacrylate (PEGMA) as the monomer and 11-bromoundecanoic acid as the initiator, which could be effectively adsorbed on GO through hydrophobic interaction. The successful preparation of GO based polymer nanocomposites was confirmed by a series of characterization techniques such as 1H nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy and X-ray photoelectron spectroscopy. The resultant products exhibit high water disperisibility, excellent biocompatibility and high efficient drug loading capability, making these PEGylated GO nanocomposites promising candidates for biomedical applications.

  10. One-pot synthesis of silica-hybridized Ag{sub 2}S–CuS nanocomposites with tunable nonlinear optical properties

    SciTech Connect

    Ann Mary, K.A.; Unnikrishnan, N.V.; Philip, Reji

    2015-10-15

    Highlights: • Silica modified QDs of CuS and Ag{sub 2}S is developed at room temperature. • Formation of Ag{sub 2}S/CuS nanocomposites is confirmed from XRD and FFT of HRTEM images. • The concentration dependent growth of silica modified QDs is discussed. • Nonlinear absorption observed in ns excitations is dominated by SA and ESA. • Tuning of optical limiting efficiency is achieved with relative Ag{sub 2}S content. - Abstract: In the present work we report a simple, facile route developed for preparing silica hybridized copper sulfide and silver sulfide quantum dots at room temperature. By adjusting the concentration of the precursors, Ag{sub 2}S can form Ag{sub 2}S–CuS nanocomposites which are self regulated in one pot. Their crystalline, structural and optical properties have been investigated in detail, and the optical limiting nature is studied from fluence-dependent transmittance measurements employing short (5 ns) laser pulses at 532 nm. Ag{sub 2}S nanoparticles are found to have large third order nonlinear optical coefficients with a relatively lower optical limiting threshold of 1.7 J cm{sup −2}, while the nonlinearity of the nanocomposites is found to lie in between that of Ag{sub 2}S and CuS nanoparticles. These results suggest pathways for designing good quality optical limiters with tunable optical limiting efficiencies by varying the constituent nanocrystal compositions.

  11. One-pot glovebox-free synthesis, characterization, and self-assembly of novel amphiphilic poly(sarcosine-b-caprolactone) diblock copolymers.

    PubMed

    Cui, Saide; Wang, Xin; Li, Zhenjiang; Zhang, Qiguo; Wu, Wenzhuo; Liu, Jingjing; Wu, Hao; Chen, Cheng; Guo, Kai

    2014-11-01

    Novel amphiphilic polypeptoid-polyester diblock copolymers based on poly(sarcosine) (PSar) and poly(ε-caprolactone) (PCL) are synthesized by a one-pot glovebox-free approach. In this method, sarcosine N-carboxy anhydride (Sar-NCA) is firstly polymerized in the presence of benzylamine under N(2) flow, then the resulting poly(sarcosine) is used in situ as the macro-initiator for the ring-opening polymerization (ROP) of ε-caprolactone using tin(II) octanoate as a catalyst. The degree of poly-merization of each block is controlled by various feed ratios of monomer/initiator. The diblock copolymers with controlled molecular weight and narrow molecular weight distributions (Đ(M) < 1.2) are characterized by (1)H NMR, (13)C NMR, and size-exclusion chromatography. The self-assembly behavior of PSar-b-PCL in water is investigated by dynamic light scattering (DLS) and transmission electron microscopy. DLS results reveal that the diblock copolymers associate into nanoparticles with average hydrodynamic diameters (D(H)) around 100 nm in water, which may be used as drug delivery carriers. PMID:25283643

  12. AlOOH-reduced graphene oxide nanocomposites: one-pot hydrothermal synthesis and their enhanced electrochemical activity for heavy metal ions.

    PubMed

    Gao, Chao; Yu, Xin-Yao; Xu, Ren-Xia; Liu, Jin-Huai; Huang, Xing-Jiu

    2012-09-26

    This work described the preparation, characterization, and electrochemical behavior toward heavy metal ions of the AlOOH-reduced graphene oxide nanocomposites. This new material was synthesized through a green one-pot hydrothermal method. The morphologic and structure of the nanocomposites were characterized using atomic force microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoemission spectroscopy, Fourier transform-infrared spectroscopy, and transmission electron microscopy. Electrochemical properties were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The chemical and electrochemical parameters that have influence on deposition and stripping of metal ions, such as pH value, deposition potential, and deposition time, were also studied. Due to the strong affinity of AlOOH to heavy metal ions and the fast electron-transfer kinetics of graphene, the combination of solid-phase extraction and stripping voltammetric analysis allowed fast and sensitive determination of Cd(II) and Pb(II) in drinking water, making these new nanocomposites promising candidates for practical applications in the fields of detecting heavy metal ions. Most importantly, these new nanocomposites may possess many unknown properties waiting to be explored. PMID:22924704

  13. In situ deposition of graphene nanosheets on wood surface by one-pot hydrothermal method for enhanced UV-resistant ability

    NASA Astrophysics Data System (ADS)

    Wan, Caichao; Jiao, Yue; Li, Jian

    2015-08-01

    Graphene nanosheets were successfully in situ deposited on the surface of the wood matrix via a mild fast one-pot hydrothermal method, and the resulting hybrid graphene/wood (GW) were characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Raman spectroscopy, and thermogravimetric analysis (TGA). According to the results, the wood matrix was evenly coated by dense uninterrupted multilayer graphene membrane structure, which was formed by layer-by-layer self-assembly of graphene nanosheets. Meanwhile, the graphene coating also induced significant improvement in the thermal stability of GW in comparison with that of the original wood (OW). Accelerated weathering tests were employed to measure and determine the UV-resistant ability of OW and GW. After about six hundred hours of experiments, the surface color change of GW was much less than that of OW; besides, the Fourier transform infrared spectroscopy (FTIR) analysis also proved the less significant changes in surface chemical compositions of GW. The results both indicated that the graphene coating effectively protected wood surface from UV damage. Therefore, this class of GW composite might be expected to be served as high-performance wooden building material for outdoor or some particular harsh environments like strong UV radiation regions use.

  14. One-pot synthesis of ternary Ag₂CO₃/Ag/AgCl photocatalyst in natural geothermal water with enhanced photocatalytic activity under visible light irradiation.

    PubMed

    Yao, Xiaxi; Liu, Xiaoheng

    2014-09-15

    Geothermal water is a clean, cheap and renewable resource and it is widely distributed all over the world. In this work, ternary Ag2CO3/Ag/AgCl photocatalyst has been successfully synthesized via a one-pot precipitation method in natural geothermal water at room temperature, wherein the geothermal water serves as the source of chlorine and carbonate. The results suggest that the Ag/AgCl nanoparticles are anchored on the surface of Ag2CO3 and Ag2CO3/Ag/AgCl composite shows strong absorption ability in the visible light region. The evaluation of the photocatalytic activity indicates that the as-synthesized Ag2CO3/Ag/AgCl photocatalyst exhibits higher photocatalytic performance for the degradation of methylene blue (MB) aqueous solution under visible light irradiation than one-component (Ag2CO3), two-component (Ag/AgCl, Ag2CO3/AgCl) and the mechanical mixture of Ag2CO3 and Ag/AgCl. The trapping experiments confirmed that holes (h(+)) and (•)O2(-) were the two main active species in the photocatalytic process. Finally, a possible Z-scheme photocatalytic mechanism of the charge transfer was proposed for the enhanced photocatalytic performance. This work may open up new insights into the application of cheap geothermal water resources in the word and provide new opportunities for facile fabrication of Ag/AgCl-based photocatalysts. PMID:25164388

  15. One-pot synthesis of water-dispersible Ag2S quantum dots with bright fluorescent emission in the second near-infrared window

    NASA Astrophysics Data System (ADS)

    Yang, Hua-Yan; Zhao, Yu-Wei; Zhang, Zheng-Yong; Xiong, Huan-Ming; Yu, Shao-Ning

    2013-02-01

    The second near-infrared window (NIR-II, wavelength of 1.0-1.4 μm) is optimal for the bioimaging of live animals due to their low albedo and endogenous autofluorescence. Herein, we report a facile and one-pot biomimetic synthesis approach to prepare water-dispersible NIR-II-emitting ultrasmall Ag2S quantum dots (QDs). Photoluminescence spectra showed that the emission peaks could be tuned from 1294 to 1050 nm as the size of the Ag2S QDs varied from 6.8 to 1.6 nm. The x-ray diffraction patterns and x-ray photoelectron spectra confirmed that the products were monoclinic α-Ag2S. Fourier transform infrared spectrograph analysis indicated that the products were protein-conjugated Ag2S QDs. Examination of cytotoxicity and the hemolysis test showed that the obtained Ag2S QDs had good biocompatibility, indicating that such a nanomaterial could be a new kind of fluorescent label for in vivo imaging.

  16. One-pot synthesis of Mn-doped TiO2 grown on graphene and the mechanism for removal of Cr(VI) and Cr(III).

    PubMed

    Chen, Zengping; Li, Yaru; Guo, Meng; Xu, Fengyun; Wang, Peng; Du, Yu; Na, Ping

    2016-06-01

    Mn-doped TiO2 grown on reduced graphene oxide(rGO) was synthesized by one-pot hydrothermal method and the photocatalytic removal of Cr by the material was investigated under sunlight. The materials were characterized by a combination of scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, Brunauer-Emmett-Teller method, UV-vis diffuse reflectance spectra, photoluminescence spectra, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. Cr(total) removal efficiency of the material is 97.32% in 30min and 99.02% in 60min under sunlight irradiation, as the initial concentration of Cr(VI) is 20mg/L. The high photocatalytic activity under visible light is considered mainly due to the Mn-doping, and rGO plays an important role in the synergetic effect of adsorption and photocatalysis to sustain the high efficient removal of Cr(VI) and Cr(III). Cr(VI) adsorbed on the surface of rGO is reduced to Cr(III) by photo electrons which are transported through rGO, and the reaction product Cr(III) continues to be adsorbed. The process contributes to the release of abundant photocatalytic sites of Mn-TiO2 and improves photocatalytic efficiency. The excellent adsorption and photocatalytic effect with the explanation of the synergetic mechanism are very useful not only for fundamental research but also for the potential practical applications. PMID:26921512

  17. One-Pot N2C/C2C/N2N Ligation To Trap Weak Protein-Protein Interactions.

    PubMed

    Zhao, Lei; Ehrt, Christiane; Koch, Oliver; Wu, Yao-Wen

    2016-07-01

    Weak transient protein-protein interactions (PPIs) play an essential role in cellular dynamics. However, it is challenging to obtain weak protein complexes owing to their short lifetime. Herein we present a general and facile method for trapping weak PPIs in an unbiased manner using proximity-induced ligations. To expand the chemical ligation spectrum, we developed novel N2N (N-terminus to N-terminus) and C2C (C-terminus to C-terminus) ligation approaches. By using N2C (N-terminus to C-terminus), N2N, and C2C ligations in one pot, the interacting proteins were linked. The weak Ypt1:GDI interaction drove C2C ligation with t1/2 of 4.8 min and near quantitative conversion. The Ypt1-GDI conjugate revealed that binding of Ypt1 G-domain causes opening of the lipid-binding site of GDI, which can accommodate one prenyl group, giving insights into Rab membrane recycling. Moreover, we used this strategy to trap the KRas homodimer, which plays an important role in Ras signaling. PMID:27213482

  18. A facile one-pot method to synthesize a polypyrrole/hemin nanocomposite and its application in biosensor, dye removal, and photothermal therapy.

    PubMed

    Hu, Peng; Han, Lei; Dong, Shaojun

    2014-01-01

    In this work, we introduced a facile method for the construction of a polypyrrole/hemin (PPy/hemin) nanocomposite via one-pot chemical oxidative polymerization. In this process, a hemin molecule serving as a dopant was entrapped in the PPy nanocomposite during chemical oxidative polymerization. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-visible spectroscopy results demonstrated that the PPy/hemin nanocomposite was successfully synthesized. The as-prepared nanocomposite exhibited intrinsic peroxidase-like catalytic activities, strong adsorption properties, and an excellent near-infrared (NIR) light-induced thermal effect. We utilized the nanomaterials to catalyze the oxidation of a peroxidase substrate 3,3,5,5-tetramethylbenzidine by H2O2 to the oxidized colored product which provided a colorimetric detection of glucose. As low as 50 μM glucose could be detected with a linear range from 0.05 to 8 mM. Moreover, the obtained nanocomposite also showed excellent removal efficiency for methyl orange and rhodamine B and a photothermal effect, which implied a promising application as the pollutant adsorbent and photothermal agent. The unique nature of the PPy/hemin nanocomposite makes it very promising for the fabrication of inexpensive, high-performance bioelectronic devices in the future. PMID:24308420

  19. Iridium ultrasmall nanoparticles, worm-like chain nanowires, and porous nanodendrites: One-pot solvothermal synthesis and catalytic CO oxidation activity

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Li, Shuai-Chen; Zhu, Wei; Ke, Jun; Yu, Jing-Wen; Zhang, Zhi-Ping; Dai, Lin-Xiu; Gu, Jun; Zhang, Ya-Wen

    2016-06-01

    We report a facile one-pot solvothermal synthesis of monodisperse iridium (Ir) ultrasmall (1.5-2.5 nm in diameter) nanoparticles (NPs), worm-like chain nanowires (NWs), and porous nanodendrites (NDs), for which CO oxidation reaction has been employed as a probe reaction to investigate the effects of nanoparticle size and surface-capping organics on the catalytic activities. Time-dependent experiments revealed that an oriented attachment mechanism induced by the strong adsorption of halide anions (Br- and I-) on specific facet of Ir nanoclusters or by decreasing the reduction rate of Ir precursors with changing their concentrations during the synthesis was responsible for the formation of Ir NWs and NDs. Annealing tests indicated that an O2-H2 atmosphere treatment turned out to be an effective measure to clean up the surface-capping organics of Ir NPs supported on commercial SiO2. Catalytic CO oxidation reaction illustrated that a significant improvement in the catalytic activity of CO oxidation reaction was achieved together with the changing of activation energies after such atmosphere treatment for the supported catalysts of the ultrasmall Ir NPs. It is noteworthy that this enhancement in catalytic activity could be ascribed to the changes in the surface status (including populations of Ir species in metallic and oxidized states, removal of surface capping organics, the variety of active sites, and total effective active site number) for the supported nanocatalysts during the atmosphere treatment.

  20. Flow immunoassay of trinitrophenol based on a surface plasmon resonance sensor using a one-pot immunoreaction with a high molecular weight conjugate.

    PubMed

    Kobayashi, Masatoshi; Sato, Masahiro; Li, Yan; Soh, Nobuaki; Nakano, Koji; Toko, Kiyoshi; Miura, Norio; Matsumoto, Kiyoshi; Hemmi, Akihide; Asano, Yasukazu; Imato, Toshihiko

    2005-12-15

    A surface plasmon resonance (SPR) immunosensor based on a competitive immunoreaction for the determination of trinitrophenol (TNP) is described. A goat anti-mouse IgG (1st antibody), which recognizes an Fc moiety of an antibody, was immobilized on a gold film of an SPR sensor chip by physical adsorption. A TNP solution containing a fixed concentration of a mouse anti-TNP monoclonal antibody (2nd antibody) and a TNP-keyhole limpet hemocyanin (KLH) conjugate was incubated in one-pot and introduced into the sensor chip. The TNP-KLH conjugate competes with TNP for binding with the 2nd antibody. The resulting complex of the 2nd antibody with the TNP-KLH conjugate was bound to the 1st antibody, which is immobilized on the sensor chip. The SPR sensor signal based on resonance angle shift is dependent on the concentration of TNP in the incubation solution in the range from 25ppt to 25ppb, and the coefficient of variation of the SPR signals for the 25ppb TNP solution was determined to be 13% (n=4). The experimental results for the adsorption constant of the 1st antibody on the sensor chip and the binding constant of the 1st antibody complex with the 2nd antibody are discussed, together with theoretical considerations. PMID:18970305

  1. One-pot synthesis, biological evaluation, and docking study of new chromeno-annulated thiopyrano[2,3-c]pyrazoles.

    PubMed

    Parmar, Bhagyashri D; Sutariya, Tushar R; Brahmbhatt, Gaurangkumar C; Parmar, Narsidas J; Kant, Rajni; Gupta, Vivek K; Murumkar, Prashant R; Sharma, Mayank Kumar; Yadav, Mange Ram

    2016-08-01

    A one-pot synthesis of new chromeno-annulated thiopyrano[2,3-c]pyrazoles has been achieved through a domino-Knoevenagel-hetero-Diels-Alder reaction after combining various pyrazol-5-thiones with O-alkenyloxy/alkynyloxy-salicylaldehydes/naphthaldehydes in a Brønsted acidic ionic liquid, [Hmim]HSO[Formula: see text], methylimidazolium hydrogen sulphate, under microwave irradiation. The method is simple and in many cases the isolated products did not require further purification. The central pyranothiopyranyl cis-fusion was confirmed by 2D NMR NOESY and single-crystal X-ray analysis suggesting that the endo-E-Syn transition state would be the most favored pathway of the reaction. Many heterocycles of this new series were found active against six bacterial and two fungal strains. In addition, all the compounds possess good anti-oxidant activity with the ferric reducing anti-oxidant power value [Formula: see text]. All new structures were docked into active site of angiotensin I converting enzyme (ACE), assuming that the compounds possessed the anti-hypertensive activity potential on the basis of prediction of activity spectra of substances prediction results. Pyranyl ring oxygen in compound 9a forms two hydrogen bonds with HIS353 and HIS513 residues in the active site of the ACE having good G score ([Formula: see text]) of this compound, comparable to that of the reference drug captopril ([Formula: see text]). PMID:27017351

  2. Ultrasound mediation for one-pot sonosynthesis and deposition of magnetite nanoparticles on cotton/polyester fabric as a novel magnetic, photocatalytic, sonocatalytic, antibacterial and antifungal textile.

    PubMed

    Rastgoo, Madine; Montazer, Majid; Malek, Reza M A; Harifi, Tina; Mahmoudi Rad, Mahnaz

    2016-07-01

    A magnetic cotton/polyester fabric with photocatalytic, sonocatalytic, antibacterial and antifungal activities was successfully prepared through in-situ sonosynthesis method under ultrasound irradiation. The process involved the oxidation of Fe(2+) to Fe(3+) via hydroxyl radicals generated through bubbles collapse in ultrasonic bath. The treated samples were analyzed by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and vibrating sample magnetometry. Photocatalytic and sonocatalytic activities of magnetite treated fabrics were also evaluated toward Reactive Blue 2 decoloration under sunlight and ultrasound irradiation. Central composite design based on response surface methodology was applied to study the influence of iron precursor, pH and surfactant concentration to obtain appropriate amount for the best magnetism. Findings suggested the potential of one-pot sonochemical method to synthesize and fabricate Fe3O4 nanoparticles on cotton/polyester fabric possessing appropriate saturation magnetization, 95% antibacterial efficiency against Staphylococcus aureus and 99% antifungal effect against Candida albicans, 87% and 70% dye photocatalytic and sonocatalytic decoloration along with enhanced mechanical properties using only one iron rich precursor at low temperature. PMID:26964948

  3. Metal Nanoparticles Covered with a Metal-Organic Framework: From One-Pot Synthetic Methods to Synergistic Energy Storage and Conversion Functions.

    PubMed

    Kobayashi, Hirokazu; Mitsuka, Yuko; Kitagawa, Hiroshi

    2016-08-01

    Hybrid materials composed of metal nanoparticles and metal-organic frameworks (MOFs) have attracted much attention in many applications, such as enhanced gas storage and catalytic, magnetic, and optical properties, because of the synergetic effects between the metal nanoparticles and MOFs. In this Forum Article, we describe our recent progress on novel synthetic methods to produce metal nanoparticles covered with a MOF (metal@MOF). We first present Pd@copper(II) 1,3,5-benzenetricarboxylate (HKUST-1) as a novel hydrogen-storage material. The HKUST-1 coating on Pd nanocrystals results in a remarkably enhanced hydrogen-storage capacity and speed in the Pd nanocrystals, originating from charge transfer from Pd nanocrystals to HKUST-1. Another material, Pd-Au@Zn(MeIM)2 (ZIF-8, where HMeIM = 2-methylimidazole), exhibits much different catalytic activity for alcohol oxidation compared with Pd-Au nanoparticles, indicating a design guideline for the development of composite catalysts with high selectivity. A composite material composed of Cu nanoparticles and Cr3F(H2O)2O{C6H3(CO2)3}2 (MIL-100-Cr) demonstrates higher catalytic activity for CO2 reduction into methanol than Cu/γ-Al2O3. We also present novel one-pot synthetic methods to produce composite materials including Pd/ZIF-8 and Ni@Ni2(dhtp) (MOF-74, where H4dhtp = 2,5-dihydroxyterephthalic acid). PMID:27322366

  4. One-pot synthesis of carbon-coated nanosized LiTi2(PO4)3 as anode materials for aqueous lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Liu, Zhantao; Qin, Xusong; Xu, Hui; Chen, Guohua

    2015-10-01

    In this study, a one-pot sintering process incorporating sol-gel preparation route and in-situ carbon coating was proposed for the synthesis of carbon-coated nanosized LiTi2(PO4)3. Experimental results show that the prepared LiTi2(PO4)3 particles are of high crystallinity and well-coated by turbostratic carbon. Attributed to nanosized particles and enhanced conductivity provided by turbostratic carbon coating, the carbon-coated LiTi2(PO4)3 showed high rate performance and good cycling life in aqueous electrolyte. Particularly, the carbon-coated LiTi2(PO4)3 exhibited initial specific capacities of 103 and 89 mAh g-1, and retained 80.6% and 97% of the initial capacities after 120 cycles at 1C and 10C in aqueous electrolyte, respectively. The high rate performance and good cycling life of carbon-coated LiTi2(PO4)3 in aqueous electrolyte reveal its potential as negative electrode in aqueous lithium-ion batteries for electric vehicles and industrial-scale energy storage systems.

  5. One-pot synthesis of high-index faceted AgCl nanocrystals with trapezohedral, concave hexoctahedral structures and their photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Zhang, Haibin; Lu, Yonggang; Liu, Hong; Fang, Jingzhong

    2015-07-01

    AgCl semiconductor nanocrystals (NCs) with trapezohedral (TPH) and concave hexoctahedral (HOH) structures have been successfully synthesized for the first time in high yield by a direct one-pot solvothermal method. The as-prepared TPH, concave HOH AgCl NCs with unconventional polyhedral shapes and smooth surfaces were enclosed by 24 high-index {311} facets and 48 high-index {15 5 2} facets, respectively. A specific ionic liquid poly(diallyldimethylammonium) chloride (PDDA) acted as both a Cl- ion precursor and a morphology-controlled stabilizer, which was indispensable for the formation of these high-index faceted AgCl polyhedra and the derived uniform octahedral AgCl in an appropriate concentration of hot AgNO3 and ethylene glycol (EG) solution. With high-index facets exposed, both TPH and concave HOH AgCl NCs exhibit much higher photocatalytic activity than octahedral AgCl NCs that have mainly {111} faces exposed, with lower surface areas and surface energies, for the degradation of organics under sunlight. It is expected that the use of polyhedral AgCl NCs with high-index facets is an effective approach for the design of alternative semiconductor photocatalysts with a high performance, which may find potential applications such as in photochromics and environmental management.

  6. One-pot hydrothermal synthesis of CuBi co-doped mesoporous zeolite Beta for the removal of NOx by selective catalytic reduction with ammonia

    PubMed Central

    Xie, Zhiguo; Zhou, Xiaoxia; Wu, Huixia; Chen, Lisong; Zhao, Han; Liu, Yan; Pan, Linyu; Chen, Hangrong

    2016-01-01

    A series of CuBi co-doped mesoporous zeolite Beta (CuxBiy-mBeta) were prepared by a facile one-pot hydrothermal treatment approach and were characterized by XRD, N2 adsorption-desorption, TEM/SEM, XPS, H2-TPR, NH3-TPD and in situ DRIFTS. The catalysts CuxBiy-mBeta were applied to the removal of NOx by selective catalytic reduction with ammonia (NH3-SCR), especially the optimized Cu1Bi1-mBeta achieved the high efficiency for the removal of NOx and N2 selectivity, superior water and sulfur resistance as well as good durability. The excellent catalytic performance could be attributed to the acid sites of the support and the synergistic effect between copper and bismuth species. Moreover, in situ DRIFTS results showed that amides NH2 and NH4+ generated from NH3 adsorption could be responsible for the high selective catalytic reduction of NOx to N2. In addition, a possible catalytic reaction mechanism on Cu1Bi1-mBeta for the removal of NOx by NH3-SCR was proposed for explaining this catalytic process. PMID:27445009

  7. Facile One-pot Transformation of Iron Oxides from Fe2O3 Nanoparticles to Nanostructured Fe3O4@C Core-Shell Composites via Combustion Waves.

    PubMed

    Shin, Jungho; Lee, Kang Yeol; Yeo, Taehan; Choi, Wonjoon

    2016-01-01

    The development of a low-cost, fast, and large-scale process for the synthesis and manipulation of nanostructured metal oxides is essential for incorporating materials with diverse practical applications. Herein, we present a facile one-pot synthesis method using combustion waves that simultaneously achieves fast reduction and direct formation of carbon coating layers on metal oxide nanostructures. Hybrid composites of Fe2O3 nanoparticles and nitrocellulose on the cm scale were fabricated by a wet impregnation process. We demonstrated that self-propagating combustion waves along interfacial boundaries between the surface of the metal oxide and the chemical fuels enabled the release of oxygen from Fe2O3. This accelerated reaction directly transformed Fe2O3 into Fe3O4 nanostructures. The distinctive color change from reddish-brown Fe2O3 to dark-gray Fe3O4 confirmed the transition of oxidation states and the change in the fundamental properties of the material. Furthermore, it simultaneously formed carbon layers of 5-20 nm thickness coating the surfaces of the resulting Fe3O4 nanoparticles, which may aid in maintaining the nanostructures and improving the conductivity of the composites. This newly developed use of combustion waves in hybridized nanostructures may permit the precise manipulation of the chemical compositions of other metal oxide nanostructures, as well as the formation of organic/inorganic hybrid nanostructures. PMID:26902260

  8. One-pot synthesis of CdS nanocrystals hybridized with single-layer transition-metal dichalcogenide nanosheets for efficient photocatalytic hydrogen evolution.

    PubMed

    Chen, Junze; Wu, Xue-Jun; Yin, Lisha; Li, Bing; Hong, Xun; Fan, Zhanxi; Chen, Bo; Xue, Can; Zhang, Hua

    2015-01-19

    Exploration of low-cost and earth-abundant photocatalysts for highly efficient solar photocatalytic water splitting is of great importance. Although transition-metal dichalcogenides (TMDs) showed outstanding performance as co-catalysts for the hydrogen evolution reaction (HER), designing TMD-hybridized photocatalysts with abundant active sites for the HER still remains challenge. Here, a facile one-pot wet-chemical method is developed to prepare MS2-CdS (M=W or Mo) nanohybrids. Surprisedly, in the obtained nanohybrids, single-layer MS2 nanosheets with lateral size of 4-10 nm selectively grow on the Cd-rich (0001) surface of wurtzite CdS nanocrystals. These MS2-CdS nanohybrids possess a large number of edge sites in the MS2 layers, which are active sites for the HER. The photocatalytic performances of WS2-CdS and MoS2-CdS nanohybrids towards the HER under visible light irradiation (>420 nm) are about 16 and 12 times that of pure CdS, respectively. Importantly, the MS2-CdS nanohybrids showed enhanced stability after a long-time test (16 h), and 70% of catalytic activity still remained. PMID:25470356

  9. Formation of core-shell-structured Zn2SnO4-carbon microspheres with superior electrochemical properties by one-pot spray pyrolysis.

    PubMed

    Hong, Young Jun; Kang, Yun Chan

    2015-01-14

    Core-shell structured Zn2SnO4-carbon microspheres with different carbon contents are prepared by one-pot spray pyrolysis without any further heating process. A Zn2SnO4-carbon composite microsphere is prepared from one droplet containing Zn and Sn salts and polyvinylpyrrolidone (PVP). Melted PVP moves to the outside of the composite microsphere during the drying stage of the droplet. In addition, melting of the phase separated metal salts forms the dense core. Carbonization of the phase separated PVP forms the textured and porous thick carbon shell. The discharge capacities of the core-shell structured Zn2SnO4-carbon microspheres for the 2(nd) and 120(th) cycles at a current density of 1 A g(-1) are 864 and 770 mA h g(-1), respectively. However, the discharge capacities of the bare Zn2SnO4 microspheres prepared by the same process without PVP for the 2(nd) and 120(th) cycles are 1106 and 81 mA h g(-1), respectively. The stable and reversible discharge capacities of the Zn2SnO4-carbon composite microspheres prepared from the spray solution with 15 g PVP decrease from 894 to 528 mA h g(-1) as current density increases from 0.5 to 5 A g(-1). PMID:25429709

  10. One-Pot Synthesis of CoSex -rGO Composite Powders by Spray Pyrolysis and Their Application as Anode Material for Sodium-Ion Batteries.

    PubMed

    Park, Gi Dae; Kang, Yun Chan

    2016-03-14

    A simple one-pot synthesis of metal selenide/reduced graphene oxide (rGO) composite powders for application as anode materials in sodium-ion batteries was developed. The detailed mechanism of formation of the CoSe(x)-rGO composite powders that were selected as the first target material in the spray pyrolysis process was studied. The crumple-structured CoSe(x)-rGO composite powders prepared by spray pyrolysis at 800 °C had a crystal structure consisting mainly of Co0.85 Se with a minor phase of CoSe2. The bare CoSe(x) powders prepared for comparison had a spherical shape and hollow structure. The discharge capacities of the CoSe(x)-rGO composite and bare CoSe(x) powders in the 50th cycle at a constant current density of 0.3 A g(-1) were 420 and 215 mA h g(-1), respectively, and their capacity retentions measured from the second cycle were 80 and 46%, respectively. The high structural stability of the CoSe(x)-rGO composite powders for repeated sodium-ion charge and discharge processes resulted in superior sodium-ion storage properties compared to those of the bare CoSe(x) powders. PMID:26864320

  11. One-pot synthesized functionalized mesoporous silica as a reversed-phase sorbent for solid-phase extraction of endocrine disrupting compounds in milks.

    PubMed

    Gañán, Judith; Morante-Zarcero, Sonia; Pérez-Quintanilla, Damián; Marina, María Luisa; Sierra, Isabel

    2016-01-01

    A new procedure for the determination of 12 naturally occurring hormones and some related synthetic chemicals in milk, commonly used as growth promoters in cattle, is reported. The method is based on liquid-liquid extraction followed by solid-phase extraction (SPE) using a new one-pot synthesized ordered mesoporous silica (of the SBA-15 type) functionalized with octadecyl groups (denoted as SBA-15-C18-CO) as reversed-phase sorbent. The analytes were eluted with methanol and then submitted to HPLC with diode array detection. Under optimal conditions, the method quantification limit for the analytes ranged from 0.023 to 1.36μg/mL. The sorbent affored the extraction of estrone, 17β-estradiol, estriol, progesterone, hexestrol, diethylstilbestrol, 4-androstene-3,17-dione, ethinylestradiol, 17α-methyltestosterone, nandrolone, prednisolone and testosterone with mean recoveries ranging from 72% to 105% (except for diethylstilbestrol) with RSD<11%. These results were comparable and, in some cases, even better than those obtained with other extraction methods, therefore SBA-15-C18-CO mesoporous silica possess a high potential as a reversed-phase sorbent for SPE of the 12 mentioned endocrine disrupting compounds in milk samples. PMID:26362809

  12. One-pot synthesis of mesoporous structured ratiometric fluorescence molecularly imprinted sensor for highly sensitive detection of melamine from milk samples.

    PubMed

    Xu, Shoufang; Lu, Hongzhi

    2015-11-15

    A facile strategy was developed to prepare mesoporous structured ratiometric fluorescence molecularly imprinted sensor for highly sensitive and selective determination of melamine using CdTe QDs as target sensitive dye and hematoporphyrin as reference dyes. One-pot synthesis method was employed because it could simplify the imprinting process and shorten the experimental period. The as-prepared fluorescence MIPs sensor, which combined ratiometric fluorescence technique with mesoporous silica materials into one system, exhibited excellent selectivity and sensitivity. Under optimum conditions, these mesoporous structured ratiometric fluorescence MIP@QDs sensors showed detection limit as low as 38 nM, which was much lower than those non-mesoporous one. The recycling process was sustainable at least 10 times without obvious efficiency decrease. The feasibility of the developed method in real samples was successfully evaluated through the analysis of melamine in raw milk and milk powder samples with satisfactory recoveries of 92-101%. The developed method proposed in this work proved to be a convenient, rapid, reliable and practical way to prepared high sensitive and selective fluorescence sensors with potentially applicable for trace pollutants analysis in complicated samples. PMID:26057736

  13. An efficient one-pot synthesis, structure, antimicrobial and antioxidant investigations of some novel quinolyldibenzo[b,e][1,4]diazepinones.

    PubMed

    Parmar, Narsidas J; Barad, Hitesh A; Pansuriya, Bhavesh R; Teraiya, Shashikant B; Gupta, Vivek K; Kant, Rajni

    2012-06-01

    A highly improved one-pot procedure for the synthesis of diazepinones, which incorporate a bioactive quinoline nucleus, under catalyst-, and solvent-free environment has been developed. The method allowed us to achieve the products in high yields without requiring a chromatographic separation. All new quinolyldibenzo[b,e][1,4]diazepinones 6a-h thus obtained were further treated to achieve N10-allylated products 7a-h by a simple allylation. The structure of all new synthesized compounds was established based on elemental analysis, mass, (1)H NMR, (13)C NMR, IR spectral data, 2D NMR experiments, and single crystal X-ray study. From in vitro antimicrobial activity studies it revealed all are active against Gram positive (Streptococcus pneumoniae, Clostridium tetani, and Bacillus subtilis), Gram negative (Salmonella typhi, Vibrio chlolerae and Escherichia coli), M. Tuberculosis H37RV bacteria, and fungus like Candia albicans and Aspergillus fumigatus. All were also found to display good antioxidant activity of a ferric reducing power. PMID:22560587

  14. A simple method to prepare modified polyethersulfone membrane with improved hydrophilic surface by one-pot: The effect of hydrophobic segment length and molecular weight of copolymers.

    PubMed

    Ran, Fen; Li, Jie; Lu, Yi; Wang, Lingren; Nie, Shengqiang; Song, Haiming; Zhao, Lei; Sun, Shudong; Zhao, Changsheng

    2014-04-01

    A simple method to prepare modified polyethersulfone (PES) membrane by one-pot is provided, and the method includes three steps: polymerization of vinyl pyrrolidone (VP), copolymerization of methyl methacrylate (MMA) and blending with PES. The effect of the PMMA segment length and molecular weight of the copolymer (PVP-b-PMMA-b-PVP, as an additive) on the structures and properties of the modified membranes was investigated. Activated partial thromboplastin time (APTT) tests indicated that with the increase of the poly(methyl methacrylate) (PMMA) segment length in the chains of the copolymers and with the increase of the molecular weight of the copolymers, the APTTs of the modified membranes increased to some extent, since less of the additives were lost during liquid-liquid phase separation process. Therefore, the copolymer was designed and prepared with appropriate ratio of poly(vinyl pyrrolidone) (PVP) to MMA and with appropriate molecular weight for better membrane performance. When the copolymer was blended in the membrane, the water permeance, protein anti-fouling property and sieving coefficients for PEG-12000 increased obviously. The simple, credible and feasible method had the potential to be used for the modification of membranes with improved blood compatibility, ultrafiltration and antifouling properties of biomaterials and for practical production. PMID:24582224

  15. One-pot synthesis of a metal–organic framework as an anode for Li-ion batteries with improved capacity and cycling stability

    SciTech Connect

    Gou, Lei Hao, Li-Min; Shi, Yong-Xin; Ma, Shou-Long; Fan, Xiao-Yong; Xu, Lei; Li, Dong-Lin Wang, Kang

    2014-02-15

    Metal–organic framework is a kind of novel electrode materials for lithium ion batteries. Here, a 3D metal–organic framework Co{sub 2}(OH){sub 2}BDC (BDC=1,4-benzenedicarboxylate) was synthesized for the first time by the reaction of Co{sup 2+} with a bio-inspired renewable organic ligand 1,4-benzenedicarboxylic acid through a solvothermal method. As an anode material for lithium ion batteries, this material exhibited an excellent cyclic stability as well as a large reversible capacity of ca. 650 mA h g{sup −1} at a current density of 50 mA g{sup −1} after 100 cycles within the voltage range of 0.02–3.0 V, higher than that of other BDC based anode. - Graphical abstract: The PXRD pattern and the cycleability curves (inset) of Co{sub 2}(OH){sub 2}BDC. Display Omitted - Highlights: • Co{sub 2}(OH){sub 2}BDC was synthesized through a one pot solvothermal process. • The solvent had a great effect on the purity of this material. • This material was used as anode material for lithium ion batteries for the first time. • Co{sub 2}(OH){sub 2}BDC showed improved capacity and cycling stability.

  16. One-pot self-assembly of graphene/carbon nanotube/sulfur hybrid with three dimensionally interconnected structure for lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Niu, Shuzhang; Lv, Wei; Zhang, Chen; Shi, Yanting; Zhao, Jianfeng; Li, Baohua; Yang, Quan-Hong; Kang, Feiyu

    2015-11-01

    A graphene/carbon nanotube (CNT)/sulfur (denoted GCS) hybrid with interconnected structure is prepared through a one-pot self-assembly approach initiated by L-ascorbic acid reduction under a mild condition. In such a solution-based assembly process, the formation of an interconnected graphene/CNT conductive network is accompanied by the uniform loading of sulfur, whose fraction is as high as of 70 wt%. The as-prepared GCS hybrid delivers an initial capacity of 1008 mAh g-1 at 0.3C and maintains 704 mAh g-1 after 100 cycles. Remarkably, at a high rate of 1.0C, the cathode shows an excellent cyclic performance with a capacity of 657 mAh g-1 after 450 ycles and the capacity decay is only 0.04% per cycle. Moreover, the superior rate performance of GCS hybrid is attributed to the conductive network formed by interconnected graphene sheets and CNT, which supply an unimpeded and continuous path for electron and Li ion transfer and accommodate the volume variation of sulfur during charge/discharge cycling. In addition, the residual functional groups on GCS can retain intimate contact of the conducting matrix with sulfur and effectively confine the diffusion of polysulfides. This study gives an eco-friendly and highly effective solution-based approach for carbon-sulfur electrode for lithium-sulfur battery.

  17. One-pot three-component domino protocol for the synthesis of novel pyrano[2,3-d]pyrimidines as antimicrobial and anti-biofilm agents.

    PubMed

    Suresh, Lingala; Poornachandra, Y; Kanakaraju, S; Ganesh Kumar, C; Chandramouli, G V P

    2015-07-14

    A simple and facile synthesis of a series of novel pyrano[2,3-d]pyrimidines has been achieved successfully via the one-pot three-component reaction of 2-amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[4,3-b]pyran-3-carbonitriles, DMF-DMA and arylamines in the presence of 1-butyl-3-methylhydrogensulphate [Bmim]HSO4 ionic liquid. This method has several advantages such as high yields, clean reaction, simple methodology and short reaction times. The synthesized compounds were evaluated for their antimicrobial activity against Gram-positive, Gram-negative and different Candida strains. Among the derivatives screened, compounds 4c, 4d, 4h and 4l were found to be active against both bacterial and Candida strains with MIC values ranging from 3.9 to 31.2 μg mL(-1). In addition, compound 4l showed a good minimum bactericidal concentration, minimum fungicidal concentration and anti-biofilm activities. Furthermore, the mode of the antifungal action for the promising compound 4l was evaluated in C. albicans MTCC 1637 through an ergosterol biosynthesis inhibition process. PMID:26054925

  18. Facile One-pot Transformation of Iron Oxides from Fe2O3 Nanoparticles to Nanostructured Fe3O4@C Core-Shell Composites via Combustion Waves

    PubMed Central

    Shin, Jungho; Lee, Kang Yeol; Yeo, Taehan; Choi, Wonjoon

    2016-01-01

    The development of a low-cost, fast, and large-scale process for the synthesis and manipulation of nanostructured metal oxides is essential for incorporating materials with diverse practical applications. Herein, we present a facile one-pot synthesis method using combustion waves that simultaneously achieves fast reduction and direct formation of carbon coating layers on metal oxide nanostructures. Hybrid composites of Fe2O3 nanoparticles and nitrocellulose on the cm scale were fabricated by a wet impregnation process. We demonstrated that self-propagating combustion waves along interfacial boundaries between the surface of the metal oxide and the chemical fuels enabled the release of oxygen from Fe2O3. This accelerated reaction directly transformed Fe2O3 into Fe3O4 nanostructures. The distinctive color change from reddish-brown Fe2O3 to dark-gray Fe3O4 confirmed the transition of oxidation states and the change in the fundamental properties of the material. Furthermore, it simultaneously formed carbon layers of 5–20 nm thickness coating the surfaces of the resulting Fe3O4 nanoparticles, which may aid in maintaining the nanostructures and improving the conductivity of the composites. This newly developed use of combustion waves in hybridized nanostructures may permit the precise manipulation of the chemical compositions of other metal oxide nanostructures, as well as the formation of organic/inorganic hybrid nanostructures. PMID:26902260

  19. One-pot hydrothermal growth of raspberry-like CeO2 on CuO microsphere as copper-based catalyst for Rochow reaction

    NASA Astrophysics Data System (ADS)

    Jin, Zheying; Li, Jing; Shi, Laishun; Ji, Yongjun; Zhong, Ziyi; Su, Fabing

    2015-12-01

    In this work, we prepared a novel structure comprising of raspberry-like CeO2 deposited on CuO microspheres (Ce-CuO) for Rochow reaction. The synthesis was carried out via a facile one-pot hydrothermal reaction without using any template, in which, the basic copper carbonate microspheres were first formed via self-assembly of basic copper carbonate nanorods, followed with deposition of cerium hydroxide. After calcination, they were transformed into Ce-CuO but still maintained the hierarchical structure, and meanwhile, mesoporous structure was formed (for simplicity, we will only state them as metal oxide in the following context). The samples were characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM) techniques. When used as a Cu-based catalyst, Ce-CuO exhibited superior catalytic property to the single CuO, CeO2 and their physically mixture in the Rochow reaction with dimethyldichlorosilane (M2) selectivity increased from ca. 65 to 83.7%. The higher M2 selectivity of Ce-CuO is mainly due to its larger surface area and the synergistic effect between CuO and CeO2. This work demonstrates that catalytic performance of the Cu-based can be improved by adding Ce rare-earth element and by carefully controlling their structures.

  20. One-pot synthesis of core-shell Cu@SiO2 nanospheres and their catalysis for hydrolytic dehydrogenation of ammonia borane and hydrazine borane

    NASA Astrophysics Data System (ADS)

    Yao, Qilu; Lu, Zhang-Hui; Zhang, Zhujun; Chen, Xiangshu; Lan, Yaqian

    2014-12-01

    Ultrafine copper nanoparticles (Cu NPs) within porous silica nanospheres (Cu@SiO2) were prepared via a simple one-pot synthetic route in a reverse micelle system and characterized by SEM, TEM, EDX, XRD, N2 adsorption-desorption, CO-TPD, XPS, and ICP methods. The characterized results show that ultrafine Cu NPs with diameter of around 2 nm are effectively embedded in the center of well-proportioned spherical SiO2 NPs of about 25 nm in diameter. Compared to commercial SiO2 supported Cu NPs, SiO2 nanospheres supported Cu NPs, and free Cu NPs, the synthesized core-shell nanospheres Cu@SiO2 exhibit a superior catalytic activity for the hydrolytic dehydrogenation of ammonia borane (AB, NH3BH3) and hydrazine borane (HB, N2H4BH3) under ambient atmosphere at room temperature. The turnover frequencies (TOF) for the hydrolysis of AB and HB in the presence of Cu@SiO2 nanospheres were measured to be 3.24 and 7.58 mol H2 (mol Cu min)-1, respectively, relatively high values for Cu nanocatalysts in the same reaction. In addition, the recycle tests show that the Cu@SiO2 nanospheres are still highly active in the hydrolysis of AB and HB, preserving 90 and 85% of their initial catalytic activity even after ten recycles, respectively.