Sample records for reaction development scope

  1. Enantioselective Decarboxylative Alkylation Reactions: Catalyst Development, Substrate Scope, and Mechanistic Studies

    PubMed Central

    Behenna, Douglas C.; Mohr, Justin T.; Sherden, Nathaniel H.; Marinescu, Smaranda C.; Harned, Andrew M.; Tani, Kousuke; Seto, Masaki; Ma, Sandy; Novák, Zoltán; Krout, Michael R.; McFadden, Ryan M.; Roizen, Jennifer L.; Enquist, John A.; White, David E.; Levine, Samantha R.; Petrova, Krastina V.; Iwashita, Akihiko; Virgil, Scott C.; Stoltz, Brian M.

    2012-01-01

    α-Quaternary ketones are accessed through novel enantioselective alkylations of allyl and propargyl electrophiles by unstabilized prochiral enolate nucleophiles in the presence of palladium complexes with various phosphinooxazoline (PHOX) ligands. Excellent yields and high enantiomeric excesses are obtained from three classes of enolate precursors: enol carbonates, enol silanes, and racemic β-ketoesters. Each of these substrate classes functions with nearly identical efficiency in terms of yield and enantioselectivity. Catalyst discovery and development, the optimization of reaction conditions, the exploration of reaction scope, and applications in target-directed synthesis are reported. Experimental observations suggest that these alkylation reactions occur through an unusual inner-sphere mechanism involving binding of the prochiral enolate nucleophile directly to the palladium center. PMID:22083969

  2. Suzuki-miyaura cross-coupling in acylation reactions, scope and recent developments.

    PubMed

    Blangetti, Marco; Rosso, Heléna; Prandi, Cristina; Deagostino, Annamaria; Venturello, Paolo

    2013-01-17

    Since the first report and due to its handiness and wide scope, the Suzuki-Miyaura (SM) cross coupling reaction has become a routine methodology in many laboratories worldwide. With respect to other common transition metal catalyzed cross couplings, the SM reaction has been so far less exploited as a tool to introduce an acyl function into a specific substrate. In this review, the various approaches found in the literature will be considered, starting from the direct SM acylative coupling to the recent developments of cross coupling between boronates and acyl chlorides or anhydrides. Special attention will be dedicated to the use of masked acyl boronates, alkoxy styryl and alkoxy dienyl boronates as coupling partners. A final section will be then focused on the acyl SM reaction as key synthetic step in the framework of natural products synthesis.

  3. Mapping the dark space of chemical reactions with extended nanomole synthesis and MALDI-TOF MS.

    PubMed

    Lin, Shishi; Dikler, Sergei; Blincoe, William D; Ferguson, Ronald D; Sheridan, Robert P; Peng, Zhengwei; Conway, Donald V; Zawatzky, Kerstin; Wang, Heather; Cernak, Tim; Davies, Ian W; DiRocco, Daniel A; Sheng, Huaming; Welch, Christopher J; Dreher, Spencer D

    2018-05-24

    Understanding the practical limitations of chemical reactions is critically important for efficiently planning the synthesis of compounds in pharmaceutical, agrochemical and specialty chemical research and development. However, literature reports of the scope of new reactions are often cursory and biased toward successful results, severely limiting the ability to predict reaction outcomes for untested substrates. We herein illustrate strategies for carrying out large scale surveys of chemical reactivity using a material-sparing nanomole-scale automated synthesis platform with greatly expanded synthetic scope combined with ultra-high throughput (uHT) matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Copyright © 2018, American Association for the Advancement of Science.

  4. 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

  5. A One-Pot/Single-Analysis Approach to Substrate Scope Investigations Using Comprehensive Two-Dimensional Gas Chromatography (GC×GC).

    PubMed

    O'Neil, Gregory W; Nelson, Robert K; Wright, Alicia M; Reddy, Christopher M

    2016-05-06

    A representative substrate scope investigation for an enantioselective catalytic ketone-reduction has been performed as a single reaction on a mixture containing equimolar amounts of nine (9) prototypical compounds. The resulting analyte pool containing 18 potential products from nine different reactions could all be completely resolved in a single chromatographic injection using comprehensive two-dimensional gas chromatography (GC×GC) with time-of-flight mass spectrometry, allowing for simultaneous determination of percent conversion and enantiomeric excess for each substrate. The results obtained for an enantioselective iron-catalyzed asymmetric transfer hydrogenation using this one-pot/single-analysis approach were similar to those reported for the individualized reactions, demonstrating the utility of this strategy for streamlining substrate scope investigations. Moreover, for this particular catalyst, activity and selectivity were not greatly affected by the presence of other ketones or enantioenriched reduced products. This approach allows for faster and greener analyses that are central to new reaction development, as well as an opportunity to gain further insights into other established transformations.

  6. Palladium-Catalyzed α-Arylation of Zinc Enolates of Esters: Reaction Conditions and Substrate Scope

    PubMed Central

    Hama, Takuo; Ge, Shaozhong; Hartwig, John F.

    2013-01-01

    The intermolecular α-arylation of esters by palladium-catalyzed coupling of aryl bromides with zinc enolates of esters is reported. Reactions of three different types of zinc enolates have been developed. α-Arylation of esters occurs in high yields with isolated Reformatsky reagents, with Reformatsky reagents generated from α-bromo esters and activated zinc, and with zinc enolates generated by quenching lithium enolates of esters with zinc chloride. The use of zinc enolates, instead of alkali metal enolates, greatly expands the scope of the arylation of esters. The reactions occur at room temperature or at 70 °C with bromoarenes containing cyano, nitro, ester, keto, fluoro, enolizable hydrogen, hydroxyl or amino functionality and with bromopyridines. The scope of esters encompasses acyclic acetates, propionates, and isobutyrates, α-alkoxyesters, and lactones. The arylation of zinc enolates of esters was conducted with catalysts bearing the hindered pentaphenylferrocenyl di-tert-butylphosphine (Q-phos) or the highly reactive dimeric Pd(I) complex {[P(t-Bu)3]PdBr}2. PMID:23931445

  7. The Suzuki-Miyaura Cross-Coupling Reaction of Halogenated Aminopyrazoles: Method Development, Scope, and Mechanism of Dehalogenation Side Reaction.

    PubMed

    Jedinák, Lukáš; Zátopková, Renáta; Zemánková, Hana; Šustková, Alena; Cankař, Petr

    2017-01-06

    The efficient Suzuki-Miyaura cross-coupling reaction of halogenated aminopyrazoles and their amides or ureas with a range of aryl, heteroaryl, and styryl boronic acids or esters has been developed. The method allowed incorporation of problematic substrates: aminopyrazoles bearing protected or unprotected pyrazole NH, as well as the free amino or N-amide group. Direct comparison of the chloro, bromo, and iodopyrazoles in the Suzuki-Miyaura reaction revealed that Br and Cl derivatives were superior to iodopyrazoles, as a result of reduced propensity to dehalogenation. Moreover, the mechanism and factors affecting the undesired dehalogenation side reaction were revealed.

  8. Towards a More Complete and Accurate Experimental Nuclear Reaction Data Library (EXFOR): International Collaboration Between Nuclear Reaction Data Centres (NRDC)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Otuka, N., E-mail: n.otsuka@iaea.org; Dupont, E.; Semkova, V.

    The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear Data Section (NDS) successfully collaborates in the maintenance and development of the EXFOR library. As the scope of published data expands (e.g. to higher energy, to heavier projectile) to meet the needs of research and applications, it has become a challenging task to maintain both the completeness and accuracy of the EXFOR library. Evolution of the library highlighting recent developments is described.

  9. Copper-Catalyzed C(sp2)-S Coupling Reactions for the Synthesis of Aryl Dithiocarbamates with Thiuram Disulfide Reagents.

    PubMed

    Dong, Zhi-Bing; Liu, Xing; Bolm, Carsten

    2017-11-03

    An efficient protocol for the copper-catalyzed preparation of aryl dithiocarbamates from aryl iodides and inexpensive, environmentally benign tetraalkylthiuram disulfides was developed. The features of mild reaction conditions, high yields, and broad substrate scope render this new approach synthetically attractive for the preparation of potentially biologically active compounds.

  10. Alkyl Aryl Ether Bond Formation with PhenoFluor**

    PubMed Central

    Shen, Xiao; Neumann, Constanze N.; Kleinlein, Claudia; Claudia, Nathaniel W.; Ritter, Tobias

    2015-01-01

    An alkyl aryl ether bond formation reaction between phenols and primary and secondary alcohols with PhenoFluor has been developed. The reaction features a broad substrate scope and tolerates many functional groups, and substrates that are challenging for more conventional ether bond forming processes may be coupled. A preliminary mechanistic study indicates reactivity distinct from conventional ether bond formation. PMID:25800679

  11. Highly effective copper-mediated gem-difluoromethylenation of arylboronic acids.

    PubMed

    Ma, Guobin; Wan, Wen; Hu, Qingyang; Jiang, Haizhen; Wang, Jing; Zhu, Shizheng; Hao, Jian

    2014-07-18

    A copper-mediated gem-difluoromethylenation of aryl, heteroaryl and vinyl boronic acids with bromodifluoromethylated oxazole or thiazole derivatives has been developed. This novel reaction showed an excellent functional group tolerance and wide substrate scope, providing facile access to practical application in drug discovery and development.

  12. A dehydrogenative cross-coupling reaction between aromatic aldehydes or ketones and dialkyl H-phosphonates for formyl or acylphenylphosphonates.

    PubMed

    Huang, Xing-Fen; Wu, Qing-Lai; He, Jian-Shi; Huang, Zhi-Zhen

    2015-04-21

    A novel DCC reaction between aromatic aldehydes or ketones and H-phosphonates has been developed for the synthesis of p-formyl or p-acylphenylphosphonates. The synthetic method has excellent para regioselectivities, good yields, and broad substrate scopes and is more benign to the environment. The DCC reaction also tolerates many functional groups, and results in a series of new p-formyl and p-acylphenylphosphonates, which should be important building blocks for the synthesis of versatile arylphosphonate derivatives.

  13. Kinugasa reactions in water: from green chemistry to bioorthogonal labelling.

    PubMed

    Chigrinova, Mariya; MacKenzie, Douglas A; Sherratt, Allison R; Cheung, Lawrence L W; Pezacki, John Paul; Pezacki, Paul

    2015-04-16

    The Kinugasa reaction has become an efficient method for the direct synthesis of β-lactams from substituted nitrones and copper(I) acetylides. In recent years, the reaction scope has been expanded to include the use of water as the solvent, and with micelle-promoted [3+2] cycloadditions followed by rearrangement furnishing high yields of β-lactams. The high yields of stable products under aqueous conditions render the modified Kinugasa reaction amenable to metabolic labelling and bioorthogonal applications. Herein, the development of methods for use of the Kinugasa reaction in aqueous media is reviewed, with emphasis on its potential use as a bioorthogonal coupling strategy.

  14. Cu/Nitroxyl Catalyzed Aerobic Oxidation of Primary Amines into Nitriles at Room Temperature

    PubMed Central

    Kim, Jinho; Stahl, Shannon S.

    2013-01-01

    An efficient catalytic method has been developed for aerobic oxidation of primary amines to the corresponding nitriles. The reactions proceed at room temperature and employ a catalyst consisting of (4,4′-tBu2bpy)CuI/ABNO (ABNO = 9-azabicyclo[3.3.1]nonan-3-one N-oxyl). The reactions exhibit excellent functional group compatibility and substrate scope, and are effective with benzylic, allylic and aliphatic amines. Preliminary mechanistic studies suggest that aerobic oxidation of the Cu catalyst is the turnover-limiting step of the reaction. PMID:24015373

  15. Gold nanoparticles supported on titanium dioxide: an efficient catalyst for highly selective synthesis of benzoxazoles and benzimidazoles.

    PubMed

    Tang, Lin; Guo, Xuefeng; Yang, Yu; Zha, Zhenggen; Wang, Zhiyong

    2014-06-11

    A highly efficient and selective reaction for the synthesis of 2-substituted benzoxazoles and benzimidazoles catalyzed by Au/TiO2 has been developed via two hydrogen-transfer processes. This reaction has a good tolerance to air and water, a wide substrate scope, and represents a new avenue for practical C-N and C-O bond formation. More importantly, no additional additives, oxidants and reductants are required for the reaction and the catalyst can be recovered and reused readily.

  16. Cu/Nitroxyl Catalyzed Aerobic Oxidation of Primary Amines into Nitriles at Room Temperature.

    PubMed

    Kim, Jinho; Stahl, Shannon S

    2013-07-05

    An efficient catalytic method has been developed for aerobic oxidation of primary amines to the corresponding nitriles. The reactions proceed at room temperature and employ a catalyst consisting of (4,4'- t Bu 2 bpy)CuI/ABNO (ABNO = 9-azabicyclo[3.3.1]nonan-3-one N -oxyl). The reactions exhibit excellent functional group compatibility and substrate scope, and are effective with benzylic, allylic and aliphatic amines. Preliminary mechanistic studies suggest that aerobic oxidation of the Cu catalyst is the turnover-limiting step of the reaction.

  17. Rhodium(III)-catalyzed three-component reaction of imines, alkynes, and aldehydes through C-H activation.

    PubMed

    Huang, Ji-Rong; Song, Qiang; Zhu, Yu-Qin; Qin, Liu; Qian, Zhi-Yong; Dong, Lin

    2014-12-15

    An efficient rhodium(III)-catalyzed tandem three-component reaction of imines, alkynes and aldehydes through CH activation has been developed. High stereo- and regioselectivity, as well as good yields were obtained in most cases. The simple and atom-economical approach offers a broad scope of substrates, providing polycyclic skeletons with potential biological properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Mechanistically Driven Development of Iridium Catalysts for Asymmetric Allylic Substitution

    PubMed Central

    Hartwig, John F.; Stanley, Levi M.

    2010-01-01

    Conspectus Enantioselective allylic substitution reactions comprise some of the most versatile methods for preparing enantiomerically enriched materials. These reactions form products that contain multiple functionalities by creating carbon–nitrogen, carbon–oxygen, carbon–carbon, and carbon–sulfur bonds. For many years, the development of catalysts for allylic substitution focused on palladium complexes. However, studies of complexes of other metals have revealed selectivities that often complement those of palladium systems. Most striking is the observation that reactions with unsymmetrical allylic electrophiles that typically occur with palladium catalysts at the less hindered site of an allylic electrophile occur at the more hindered site with catalysts based on other metals. In this Account, we describe an iridium precursor and a phosphoramidite ligand that catalyze reactions with a particularly broad scope of nucleophiles. The active form of this iridium catalyst is not generated by the simple binding of the phosphoramidite ligand to the metal precursor. Instead, the initial phosphoramidite and iridium precursor react in the presence of base to form a metallacyclic species that is the active catalyst. This species is generated either in situ or separately in isolated form by reactions with added base. The identification of the structure of the active catalyst led to the development of simplified catalysts as well as the most active form of the catalyst now available, which is stabilized by a loosely bound ethylene. Most recently, this structure was used to prepare intermediates containing allyl ligands, the structures of which provide a model for the enantioselectivities discussed here. Initial studies from our laboratory on the scope of iridium-catalyzed allylic substitution showed that reactions of primary and secondary amines, including alkylamines, benzylamines, and allylamines, and reactions of phenoxides and alkoxides occurred in high yields, with high branched-to-linear ratios and high enantioselectivities. Parallel mechanistic studies had revealed the metallacyclic structure of the active catalyst, and subsequent experiments with the purposefully formed metallacycle increased the reaction scope dramatically. Aromatic amines, azoles, ammonia, and amides and carbamates as ammonia equivalents all reacted with high selectivities and yields. Moreover, weakly basic enolates (such as silyl enol ethers) and enolate equivalents (such as enamines) also reacted, and other research groups have used this catalyst to conduct reactions of stabilized carbon nucleophiles in the absence of additional base. One hallmark of the reactions catalyzed by this iridium system is the invariably high enantioselectivity, which reflects a high stereoselectivity for formation of the allyl intermediate. Enantioselectivity typically exceeds 95%, regioselectivity for formation of branched over linear products is usually near 20:1, and yields generally exceed 75% and are often greater than 90%. Thus, the development of iridium catalysts for enantioselective allylic substitution shows how studies of reaction mechanism can lead to a particularly active and a remarkably general system for an enantioselective process. In this case, a readily accessible catalyst effects allylic substitution, with high enantioselectivity and regioselectivity complementary to that of the venerable palladium systems. PMID:20873839

  19. Biocatalytic site- and enantioselective oxidative dearomatization of phenols

    NASA Astrophysics Data System (ADS)

    Baker Dockrey, Summer A.; Lukowski, April L.; Becker, Marc R.; Narayan, Alison R. H.

    2018-02-01

    The biocatalytic transformations used by chemists are often restricted to simple functional-group interconversions. In contrast, nature has developed complexity-generating biocatalytic reactions within natural product pathways. These sophisticated catalysts are rarely employed by chemists, because the substrate scope, selectivity and robustness of these catalysts are unknown. Our strategy to bridge the gap between the biosynthesis and synthetic chemistry communities leverages the diversity of catalysts available within natural product pathways. Here we show that, starting from a suite of biosynthetic enzymes, catalysts with complementary substrate scope as well as selectivity can be identified. This strategy has been applied to the oxidative dearomatization of phenols, a chemical transformation that rapidly builds molecular complexity from simple starting materials and cannot be accomplished with high selectivity using existing catalytic methods. Using enzymes from biosynthetic pathways, we have successfully developed a method to produce ortho-quinol products with controlled site- and stereoselectivity. Furthermore, we have capitalized on the scalability and robustness of this method in gram-scale reactions as well as multi-enzyme and chemoenzymatic cascades.

  20. Development of multiplex polymerase chain reaction for detection of Ehrlichia canis, Babesia spp and Hepatozoon canis in canine blood.

    PubMed

    Kledmanee, Kan; Suwanpakdee, Sarin; Krajangwong, Sakranmanee; Chatsiriwech, Jarin; Suksai, Parut; Suwannachat, Pongpun; Sariya, Ladawan; Buddhirongawatr, Ruangrat; Charoonrut, Phingphol; Chaichoun, Kridsada

    2009-01-01

    A multiplex polymerase chain reaction (PCR) has been developed for simultaneous detection of canine blood parasites, Ehrlichia canis, Babesia spp and Hepatozoon canis, from blood samples in a single reaction. The multiplex PCR primers were specific to E. canis VirB9, Babesia spp 16S rRNA and H. canis 16S rRNA genes. Specificity of the amplicons was confirmed by DNA sequencing. The assay was evaluated using normal canine and infected blood samples, which were detected by microscopic examination. This multiplex PCR offers scope for simultaneous detection of three important canine blood parasites and should be valuable in monitoring parasite infections in dogs and ticks.

  1. Development of a test for recording both visual and auditory reaction times, potentially useful for future studies in patients on opioids therapy

    PubMed Central

    Miceli, Luca; Bednarova, Rym; Rizzardo, Alessandro; Samogin, Valentina; Della Rocca, Giorgio

    2015-01-01

    Objective Italian Road Law limits driving while undergoing treatment with certain kinds of medication. Here, we report the results of a test, run as a smartphone application (app), assessing auditory and visual reflexes in a sample of 300 drivers. The scope of the test is to provide both the police force and medication-taking drivers with a tool that can evaluate the individual’s capacity to drive safely. Methods The test is run as an app for Apple iOS and Android mobile operating systems and facilitates four different reaction times to be assessed: simple visual and auditory reaction times and complex visual and auditory reaction times. Reference deciles were created for the test results obtained from a sample of 300 Italian subjects. Results lying within the first three deciles were considered as incompatible with safe driving capabilities. Results Performance is both age-related (r>0.5) and sex-related (female reaction times were significantly slower than those recorded for male subjects, P<0.05). Only 21% of the subjects were able to perform all four tests correctly. Conclusion We developed and fine-tuned a test called Safedrive that measures visual and auditory reaction times through a smartphone mobile device; the scope of the test is two-fold: to provide a clinical tool for the assessment of the driving capacity of individuals taking pain relief medication; to promote the sense of social responsibility in drivers who are on medication and provide these individuals with a means of testing their own capacity to drive safely. PMID:25709406

  2. Development of a test for recording both visual and auditory reaction times, potentially useful for future studies in patients on opioids therapy.

    PubMed

    Miceli, Luca; Bednarova, Rym; Rizzardo, Alessandro; Samogin, Valentina; Della Rocca, Giorgio

    2015-01-01

    Italian Road Law limits driving while undergoing treatment with certain kinds of medication. Here, we report the results of a test, run as a smartphone application (app), assessing auditory and visual reflexes in a sample of 300 drivers. The scope of the test is to provide both the police force and medication-taking drivers with a tool that can evaluate the individual's capacity to drive safely. The test is run as an app for Apple iOS and Android mobile operating systems and facilitates four different reaction times to be assessed: simple visual and auditory reaction times and complex visual and auditory reaction times. Reference deciles were created for the test results obtained from a sample of 300 Italian subjects. Results lying within the first three deciles were considered as incompatible with safe driving capabilities. Performance is both age-related (r>0.5) and sex-related (female reaction times were significantly slower than those recorded for male subjects, P<0.05). Only 21% of the subjects were able to perform all four tests correctly. We developed and fine-tuned a test called Safedrive that measures visual and auditory reaction times through a smartphone mobile device; the scope of the test is two-fold: to provide a clinical tool for the assessment of the driving capacity of individuals taking pain relief medication; to promote the sense of social responsibility in drivers who are on medication and provide these individuals with a means of testing their own capacity to drive safely.

  3. STRATEGIES FOR GREEN REACTION CHEMISTRIES: APPLICATION OF GREEN CATALYSIS AND PROCESS INTENSIFICATION

    EPA Science Inventory

    An intramural research effort within the Sustainable Technology Division (STD) is focused on the development of novel technologies for the synthesis of chemicals in a green and sustainable manner. To extend on the scope of green chemistry, this research also incorporates enginee...

  4. Gold Redox Catalysis through Base-Initiated Diazonium Decomposition toward Alkene, Alkyne, and Allene Activation.

    PubMed

    Dong, Boliang; Peng, Haihui; Motika, Stephen E; Shi, Xiaodong

    2017-08-16

    The discovery of photoassisted diazonium activation toward gold(I) oxidation greatly extended the scope of gold redox catalysis by avoiding the use of a strong oxidant. Some practical issues that limit the application of this new type of chemistry are the relative low efficiency (long reaction time and low conversion) and the strict reaction condition control that is necessary (degassing and inert reaction environment). Herein, an alternative photofree condition has been developed through Lewis base induced diazonium activation. With this method, an unreactive Au I catalyst was used in combination with Na 2 CO 3 and diazonium salts to produce a Au III intermediate. The efficient activation of various substrates, including alkyne, alkene and allene was achieved, followed by rapid Au III reductive elimination, which yielded the C-C coupling products with good to excellent yields. Relative to the previously reported photoactivation method, our approach offered greater efficiency and versatility through faster reaction rates and broader reaction scope. Challenging substrates such as electron rich/neutral allenes, which could not be activated under the photoinitiation conditions (<5 % yield), could be activated to subsequently yield the desired coupling products in good to excellent yield. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Tandem SN2' nucleophilic substitution/oxidative radical cyclization of aryl substituted allylic alcohols with 1,3-dicarbonyl compounds.

    PubMed

    Zhang, Zhen; Li, Cheng; Wang, Shao-Hua; Zhang, Fu-Min; Han, Xue; Tu, Yong-Qiang; Zhang, Xiao-Ming

    2017-04-11

    A novel and efficient tandem S N 2' nucleophilic substitution/oxidative radical cyclization reaction of aryl substituted allylic alcohols with 1,3-dicarbonyl compounds has been developed by using Mn(OAc) 3 as an oxidant, which enables the expeditious synthesis of polysubstituted dihydrofuran (DHF) derivatives in moderate to high yields. The use of weakly acidic hexafluoroisopropanol (HFIP) as the solvent rather than AcOH has successfully improved the yields and expanded the substrate scope of this type of radical cyclization reactions. Mechanistic studies confirmed the cascade reaction process involving a final radical cyclization.

  6. A Cycloaromatization Protocol for Synthesis of Polysubstituted Phenol Derivatives: Method Development and Mechanistic Studies

    PubMed Central

    Spencer, William T.

    2012-01-01

    The scope of the cycloaromatization of propargylic ethers was explored using operationally simple air- and moisture-insensitive conditions. Highly substituted phenol derivatives were obtained in high yields. Mechanistic experiments indicate that the reaction occurs by an electrocyclization followed by 1,3-proton transfer. PMID:22891882

  7. Toys and games in play therapy.

    PubMed

    Meschiany, A; Krontal, S

    1998-01-01

    The present article discusses the difference between play therapy with toys and play therapy with games from a psychodynamic point of view. Toys are regarded as offering the child an opportunity to develop a variety of transference reactions, while games, because of their inherent competitive characteristic, restrain the scope of possible transference reactions. The authors claim that therapists should consider these eventualities when choosing which games or toys are to be available in the therapy room. This choice might determine, in advance, the initial characteristics of the patient's transference.

  8. Virtually Instantaneous, Room-temperature [11C]-Cyanation Using Biaryl Phosphine Pd(0) Complexes

    PubMed Central

    Lee, Hong Geun; Milner, Phillip J.; Placzek, Michael S.; Buchwald, Stephen L.; Hooker, Jacob M.

    2015-01-01

    A new radiosynthetic protocol for the preparation of [11C]aryl nitriles has been developed. This process is based on the direct reaction of in situ prepared L•Pd(Ar)X complexes (L=biaryl phosphine) with [11C]HCN. The strategy is operationally simple, exhibits a remarkably wide substrate scope with short reaction times, and demonstrates superior reactivity compared to previously reported systems. With this procedure, a variety of [11C]nitrile-containing pharmaceuticals were prepared with high radiochemical efficiency. PMID:25565277

  9. Recent advances in sortase-catalyzed ligation methodology.

    PubMed

    Antos, John M; Truttmann, Matthias C; Ploegh, Hidde L

    2016-06-01

    The transpeptidation reaction catalyzed by bacterial sortases continues to see increasing use in the construction of novel protein derivatives. In addition to growth in the number of applications that rely on sortase, this field has also seen methodology improvements that enhance reaction performance and scope. In this opinion, we present an overview of key developments in the practice and implementation of sortase-based strategies, including applications relevant to structural biology. Topics include the use of engineered sortases to increase reaction rates, the use of redesigned acyl donors and acceptors to mitigate reaction reversibility, and strategies for expanding the range of substrates that are compatible with a sortase-based approach. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. The synthesis of highly functionalised pyridines using Ghosez-type reactions of dihydropyrazoles.

    PubMed

    Catti, Federica; Kiuru, Paula S; Slawin, Alexandra M Z; Westwood, Nicholas J

    2008-09-29

    The aza-Diels-Alder reaction of αβ-unsaturated hydrazones is a general methodology that has been applied both to the synthesis of natural products and in the development of multicomponent reactions. Trends have emerged as to the effect of substituents on the efficiency of this reaction with substituents at the C2 and C4-positions of the aza-diene in general suppressing the reaction. Here we report that 4,5-dihydropyrazoles can function as substrates in this process despite the presence of substituents at both of these positions. A one pot, four chemical step sequence carried out under standard thermal or microwave conditions results in the formation of the corresponding pyridine-containing compounds. The scope of the reaction is explored and additional insights into the proposed mechanism of this reaction are provided.

  11. Marrow-Derived Antibody Library for Treatment of Neuroblastoma

    DTIC Science & Technology

    2013-09-01

    to capture the auto-immune response reaction in neuroblastoma patients using phage display and B cell hybridoma technologies. The scope of this...project is to use NB patient-derived materials to create NB cell lines, xenograft models, NB specific phage display libraries and to identify and...the auto-immune response reaction in neuroblastoma patients using phage display and B cell hybridoma technologies. The scope of this project is to

  12. 40 CFR 717.1 - Scope and compliance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... HEALTH OR THE ENVIRONMENT General Provisions § 717.1 Scope and compliance. Section 8 (c) of the Toxic... mixtures: (a) To keep “records of significant adverse reactions to health or the environment, as determined... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Scope and compliance. 717.1 Section...

  13. Atherton–Todd reaction: mechanism, scope and applications

    PubMed Central

    Le Corre, Stéphanie S; Berchel, Mathieu; Couthon-Gourvès, Hélène; Haelters, Jean-Pierre

    2014-01-01

    Summary Initially, the Atherton–Todd (AT) reaction was applied for the synthesis of phosphoramidates by reacting dialkyl phosphite with a primary amine in the presence of carbon tetrachloride. These reaction conditions were subsequently modified with the aim to optimize them and the reaction was extended to different nucleophiles. The mechanism of this reaction led to controversial reports over the past years and is adequately discussed. We also present the scope of the AT reaction. Finally, we investigate the AT reaction by means of exemplary applications, which mainly concern three topics. First, we discuss the activation of a phenol group as a phosphate which allows for subsequent transformations such as cross coupling and reduction. Next, we examine the AT reaction applied to produce fire retardant compounds. In the last section, we investigate the use of the AT reaction for the production of compounds employed for biological applications. The selected examples to illustrate the applications of the Atherton–Todd reaction mainly cover the past 15 years. PMID:24991268

  14. Copper-Catalyzed Electrophilic Amination of Organoaluminum Nucleophiles with O-Benzoyl Hydroxylamines.

    PubMed

    Zhou, Shuangliu; Yang, Zhiyong; Chen, Xu; Li, Yimei; Zhang, Lijun; Fang, Hong; Wang, Wei; Zhu, Xiancui; Wang, Shaowu

    2015-06-19

    A copper-catalyzed electrophilic amination of aryl and heteroaryl aluminums with N,N-dialkyl-O-benzoyl hydroxylamines that affords the corresponding anilines in good yields has been developed. The catalytic reaction proceeds very smoothly under mild conditions and exhibits good substrate scope. Moreover, the developed catalytic system is also well suited for heteroaryl aluminum nucleophiles, providing facile access to heteroaryl amines.

  15. Development of the Off-line Analysis Code for GODDESS

    NASA Astrophysics Data System (ADS)

    Garland, Heather; Cizewski, Jolie; Lepailleur, Alex; Walters, David; Pain, Steve; Smith, Karl

    2016-09-01

    Determining (n, γ) cross sections on unstable nuclei is important for understanding the r-process that is theorized to occur in supernovae and neutron-star mergers. However, (n, γ) reactions are difficult to measure directly because of the short lifetime of the involved neutron rich nuclei. A possible surrogate for the (n, γ) reaction is the (d,p γ) reaction; the measurement of these reactions in inverse kinematics is part of the scope of GODDESS - Gammasphere ORRUBA (Oak Ridge Rutgers University Barrel Array): Dual Detectors for Experimental Structure Studies. The development of an accurate and efficient off-line analysis code for GODDESS experiments is not only essential, but also provides a unique opportunity to create an analysis code designed specifically for transfer reaction experiments. The off-line analysis code has been developed to produce histograms from the binary data file to determine how to best sort events. Recent developments in the off-line analysis code will be presented as well as details on the energy and position calibrations for the ORRUBA detectors. This work is supported in part by the U.S. Department of Energy and National Science Foundation.

  16. 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...

  17. 29 CFR 1918.100 - Emergency action plans.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... emergency action or for reaction time for safe escape of employees from the workplace or the immediate work... 29 Labor 7 2010-07-01 2010-07-01 false Emergency action plans. 1918.100 Section 1918.100 Labor... action plans. (a) Scope and application. This section requires all employers to develop and implement an...

  18. A General, Efficient and Functional-Group-Tolerant Catalyst System for the Palladium-Catalyzed Thioetherification of Aryl Bromides and Iodides

    PubMed Central

    Fernández-Rodríguez, Manuel A.; Hartwig, John F.

    2010-01-01

    The cross-coupling reaction of aryl bromides and iodides with aliphatic and aromatic thiols catalyzed by palladium complexes of the bisphosphine ligand CyPF-tBu (1) is reported. Reactions occur in excellent yields, broad scope, high tolerance of functional groups and with turnover numbers that exceed those of previous catalysts by two or three orders of magnitude. These couplings of bromo- and iodoarenes are more efficient than the corresponding reactions of chloroarenes and could be conducted with less catalyst loading and/or milder reaction conditions. Consequently, limitations regarding scope and functional group tolerance previously reported in the coupling of aryl chlorides are now overcome. PMID:19154131

  19. The intermolecular Pauson-Khand reaction.

    PubMed

    Gibson, Susan E; Mainolfi, Nello

    2005-05-13

    Five membered carbocycles are important building blocks for many biologically active molecules. Moreover, substituted cyclopentenones (e.g. cyclopentenone prostaglandins) exhibit characteristic biological activity. The efficiency and atom economy of the Pauson-Khand reaction render this process potentially one of the most attractive methods for the synthesis of such compounds. Although it was discovered in its intermolecular form, the scope of the intermolecular Pauson-Khand reaction has always been limited by the poor reactivity and selectivity of the alkene component. The past decade, especially the last three years, has seen concerted efforts to broaden the scope of this reaction. In this overview, we provide a comprehensive and critical coverage of the intermolecular Pauson-Khand reaction based on the reactivity characteristics of different classes of alkenes and a rationalization of successes and misfortunes in this area.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Otuka, N.; Pritychenko, B.; Otuka, N.

    The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear Data Section (NDS) successfully collaborates in the maintenance and development of the EXFOR library. Likewise, as the scope of published data expands (e.g. to higher energy, to heavier projectile) to meet the needs of research and applications, it has become a challenging task to maintain both the completeness and accuracy of the EXFOR library. Evolution of the library highlighting recent developments is described.

  1. Alkene metathesis: the search for better catalysts.

    PubMed

    Deshmukh, Prashant H; Blechert, Siegfried

    2007-06-28

    Alkene metathesis catalyst development has made significant progress over recent years. Research in metathesis catalyst design has endeavoured to tackle three key issues: those of (i) catalyst efficiency and activity, (ii) substrate scope and selectivity--particularly stereoselective metathesis reactions--and (iii) the minimization of metal impurities and catalyst recycling. This article describes a brief history of metathesis catalyst development, followed by a survey of more recent research, with a particular emphasis on ruthenium catalysts.

  2. Asymmetric Synthesis of Secondary and Tertiary Propargylic Alcohols by Umpolung of Acetylenic Sulfones and ortho-Sulfinyl Carbanions.

    PubMed

    Rodríguez, Ricardo I; Ramírez, Elsie; Yuste, Francisco; Sánchez-Obregón, Rubén; Alemán, José

    2018-02-16

    The generation of diastereomerically enriched secondary benzyl propargyl alcohols by the asymmetric addition of ortho-sulfinylbenzyl carbanions to sulfonylacetylene derivatives via formation of a Csp-Csp 3 bond is described. This reaction proceeds through an unusual α-attack (anti-Michael addition) of the ortho-sulfinylbenzyl carbanions, followed by elimination of the arylsulfonyl moiety. The scope of this alkynylation reaction is also discussed. Moreover, the development of a new approach for the synthesis of optically active tertiary benzylpropargyl alcohols is described, discussing the possible stereocourse of the reaction so as the influence of the ether 18-crown-6 and steric importance of acetylenic substituent.

  3. Murai Reaction on Furfural Derivatives Enabled by Removable N,N'-Bidentate Directing Groups.

    PubMed

    Pezzetta, Cristofer; Veiros, Luis F; Oble, Julie; Poli, Giovanni

    2017-06-22

    Furfural and related compounds are industrially relevant building blocks obtained from lignocellulosic biomass. To enhance the added value of these renewable resources, a Ru-catalyzed hydrofurylation of alkenes, involving a directed C-H activation at C3 of the furan ring, was developed. A thorough experimental study revealed that a bidentate amino-imine directing group enabled the desired coupling. Removal of the directing group occurred during the purification step, directly releasing the C3-functionalized furfurals. Development of the reaction as well as optimization and scope of the method were described. A mechanism was proposed on the basis of DFT calculations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Iron-catalyzed electrochemical C-H perfluoroalkylation of arenes.

    PubMed

    Khrizanforov, Mikhail; Strekalova, Sofia; Khrizanforova, Vera; Grinenko, Valeriya; Kholin, Kirill; Kadirov, Marsil; Burganov, Timur; Gubaidullin, Aidar; Gryaznova, Tatyana; Sinyashin, Oleg; Xu, Long; Vicic, David A; Budnikova, Yulia

    2015-12-07

    A new iron-catalyzed reaction for the coupling of perfluoroalkyl iodides (RFI) with aromatic substrates is described. The perfluoroalkylated arene products are obtained in good to excellent yields in the presence of a [(bpy)Fe(ii)] catalyst (10%) electrochemically regenerated or generated from [(bpy)Fe(iii)] at room temperature. The development, scope, and preliminary mechanistic studies of these transformations are reported.

  5. Technical Work Plan for: Thermodynamic Database for Chemical Modeling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    C.F. Jovecolon

    The objective of the work scope covered by this Technical Work Plan (TWP) is to correct and improve the Yucca Mountain Project (YMP) thermodynamic databases, to update their documentation, and to ensure reasonable consistency among them. In addition, the work scope will continue to generate database revisions, which are organized and named so as to be transparent to internal and external users and reviewers. Regarding consistency among databases, it is noted that aqueous speciation and mineral solubility data for a given system may differ according to how solubility was determined, and the method used for subsequent retrieval of thermodynamic parametermore » values from measured data. Of particular concern are the details of the determination of ''infinite dilution'' constants, which involve the use of specific methods for activity coefficient corrections. That is, equilibrium constants developed for a given system for one set of conditions may not be consistent with constants developed for other conditions, depending on the species considered in the chemical reactions and the methods used in the reported studies. Hence, there will be some differences (for example in log K values) between the Pitzer and ''B-dot'' database parameters for the same reactions or species.« less

  6. 40 CFR 717.1 - Scope and compliance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ACT RECORDS AND REPORTS OF ALLEGATIONS THAT CHEMICAL SUBSTANCES CAUSE SIGNIFICANT ADVERSE REACTIONS TO... mixtures: (a) To keep “records of significant adverse reactions to health or the environment, as determined...

  7. 40 CFR 717.1 - Scope and compliance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ACT RECORDS AND REPORTS OF ALLEGATIONS THAT CHEMICAL SUBSTANCES CAUSE SIGNIFICANT ADVERSE REACTIONS TO... mixtures: (a) To keep “records of significant adverse reactions to health or the environment, as determined...

  8. Pharmacogenetics of drugs withdrawn from the market.

    PubMed

    Zhang, Wei; Roederer, Mary W; Chen, Wang-Qing; Fan, Lan; Zhou, Hong-Hao

    2012-01-01

    The safety and efficacy of candidate compounds are critical factors during the development of drugs, and most drugs have been withdrawn from the market owing to severe adverse reactions. Individuals/populations with different genetic backgrounds may show significant differences in drug metabolism and efficacy, which can sometimes manifest as severe adverse drug reactions. With an emphasis on the mechanisms underlying abnormal drug effects caused by genetic mutations, pharmacogenetic studies may enhance the safety and effectiveness of drug use, provide more comprehensive delineations of the scope of usage, and change the fates of drugs withdrawn from the market.

  9. Tandem catalytic allylic amination and [2,3]-Stevens rearrangement of tertiary amines.

    PubMed

    Soheili, Arash; Tambar, Uttam K

    2011-08-24

    We have developed a catalytic allylic amination involving tertiary aminoesters and allylcarbonates, which is the first example of the use of tertiary amines as intermolecular nucleophiles in metal-catalyzed allylic substitution chemistry. This process is employed in a tandem ammonium ylide generation/[2,3]-rearrangement reaction, which formally represents a palladium-catalyzed Stevens rearrangement. Low catalyst loadings and mild reaction conditions are compatible with an unprecedented substrate scope for the ammonium ylide functionality, and products are generated in high yields and diastereoselectivities. Mechanistic studies suggested the reversible formation of an ammonium intermediate.

  10. 40 CFR 710.4 - Scope of the inventory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... not included. (3) Any chemical substance which results from a chemical reaction that occurs incidental... reaction that occurs incidental to storage of another chemical substance, mixture, or article. (5) Any chemical substance which results from a chemical reaction that occurs upon end use of other chemical...

  11. 40 CFR 710.4 - Scope of the inventory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... not included. (3) Any chemical substance which results from a chemical reaction that occurs incidental... reaction that occurs incidental to storage of another chemical substance, mixture, or article. (5) Any chemical substance which results from a chemical reaction that occurs upon end use of other chemical...

  12. 40 CFR 710.4 - Scope of the inventory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... not included. (3) Any chemical substance which results from a chemical reaction that occurs incidental... reaction that occurs incidental to storage of another chemical substance, mixture, or article. (5) Any chemical substance which results from a chemical reaction that occurs upon end use of other chemical...

  13. The Palladium-Catalyzed Aerobic Kinetic Resolution of Secondary Alcohols: Reaction Development, Scope, and Applications

    PubMed Central

    Ebner, David C.; Bagdanoff, Jeffrey T.; Ferreira, Eric M.; McFadden, Ryan M.; Caspi, Daniel D.; Trend, Raissa M.

    2010-01-01

    The first palladium-catalyzed enantioselective oxidation of secondary alcohols has been developed, utilizing the readily available diamine (−)-sparteine as chiral ligand and molecular oxygen as the stoichiometric oxidant. Mechanistic insights regarding the role of base and hydrogen bond donors have resulted in several improvements to the original system. Namely, addition of cesium carbonate and tert-butyl alcohol greatly enhances reaction rates, promoting rapid resolutions. The use of chloroform as solvent allows the use of ambient air as the terminal oxidant at 23 °C, resulting in enhanced catalyst selectivity. These improved reaction conditions have permitted the successful kinetic resolution of benzylic, allylic, and cyclopropyl secondary alcohols to high enantiomeric excess with good to excellent selectivity factors. This catalyst system has also been applied to the desymmetrization of meso-diols, providing high yields of enantioenriched hydroxyketones. PMID:19904777

  14. Rhenium-catalyzed deoxydehydration of diols and polyols.

    PubMed

    Dethlefsen, Johannes R; Fristrup, Peter

    2015-03-01

    The substitution of platform chemicals of fossil origin by biomass-derived analogues requires the development of chemical transformations capable of reducing the very high oxygen content of biomass. One such reaction, which has received increasing attention within the past five years, is the rhenium-catalyzed deoxydehydration (DODH) of a vicinal diol into an alkene; this is a model system for abundant polyols like glycerol and sugar alcohols. The present contribution includes a review of early investigations of stoichiometric reactions involving rhenium, diols, and alkenes followed by a discussion of the various catalytic systems that have been developed with emphasis on the nature of the reductant, the substrate scope, and mechanistic investigations. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Copper- and copper–N-heterocyclic carbene-catalyzed C─H activating carboxylation of terminal alkynes with CO2 at ambient conditions

    PubMed Central

    Yu, Dingyi; Zhang, Yugen

    2010-01-01

    The use of carbon dioxide as a renewable and environmentally friendly source of carbon in organic synthesis is a highly attractive approach, but its real world applications remain a great challenge. The major obstacles for commercialization of most current protocols are their low catalytic performances, harsh reaction conditions, and limited substrate scope. It is important to develop new reactions and new protocols for CO2 transformations at mild conditions and in cost-efficient ways. Herein, a copper-catalyzed and copper–N-heterocyclic carbene-cocatalyzed transformation of CO2 to carboxylic acids via C─H bond activation of terminal alkynes with or without base additives is reported. Various propiolic acids were synthesized in good to excellent yields under ambient conditions without consumption of any organometallic or organic reagent additives. This system has a wide scope of substrates and functional group tolerances and provides a powerful tool for the synthesis of highly functionalized propiolic acids. This catalytic system is a simple and economically viable protocol with great potential in practical applications. PMID:21059950

  16. Conversion of zirconacyclopentadienes into metalloles: Fagan-Nugent reaction and beyond.

    PubMed

    Yan, Xiaoyu; Xi, Chanjuan

    2015-04-21

    Metalloles are derivatives of cyclopentadiene in which the methylene unit is replaced by a heteroatom, such as S, Se, Te, N, P, As, Sb, Bi, Si, Ge, Sn, B, Al, Ga, and so on. Many metallole derivatives have been widely used as photovoltaic cells, organic light emitting diodes (OLEDs), chemical sensors, electrochromic devices, microelectronic actuators, and organic field effect transistors (OFETs). In the meantime, many of them showed promising biological actives. Due to the similarity to cyclopentadiene, the anionic forms of metalloles were also widely explored in coordination chemistry. As a result, development of a general method for the formation of metalloles from available starting materials is highly desired. In this Account, we outline formation of various p-block element metalloles from zirconacyclopentadienes. The zirconacyclopentadienes can be easily prepared from two molecules of alkynes and a low-valent zirconocene species "Cp2Zr(II)" (Cp = cyclopentadienyl). Fagan and Nugent first reported the formation of main group metalloles from zirconacyclopentadiene, which provided a versatile approach for the construction of metalloles, especially for the formation of metalloles in heavier p-block elements. To further expand the substrate scope, a number of stepwise conversions were developed, which involve 1,4-dimetallo- or dihalo-1,3-butadiene as intermediates from zirconacyclopentadienes. Here, four processes are classified based on direct and indirect conversion of zirconacyclopentadienes into metalloles. Direct reaction of zirconacyclopentadienes with element halides afforded heterocycles of main group elements, which provided a versatile method for the synthesis of metalloles. Nonetheless, the reaction scope was restricted to heavier p-block elements such as S, Se, P, As, Sb, Bi, Ge, Sn, Ga, and In. And these reactions usually suffered low yields and long reaction time. Transmetalation of zirconacyclopentadiene with copper chloride greatly enriched the zirconacyclopentadiene chemistry. The synthesis of stannoles and pyrroles from zirconacyclopentadienes has been developed in the presence of CuCl. The direct reaction of the zirconacyclopentadienes with SiCl4 or R2SiCl2 does not give the desired silacyclopendadiene derivatives, even in the presence of CuCl. It can be circumvented by using dilithiated dienes from diiododienes, which are easily prepared by the iodination of zirconacyclopentadienes using CuCl as an additive. Finally, an umpolung strategy, reaction of electrophilic 1,4-diiodo-1,3-butadiene with nucleophilic amine or sulfide reagents, was successfully used in the formation of pyrroles and thiophenes.

  17. Psychodynamics and treatment of sexual assualt victims.

    PubMed

    Schuker, E

    1979-10-01

    This paper discusses (1) how my own interest in the treatment of sexual assualt victims developed and how I view the scope of this problem; (2) myths and facts about sexual assault; (3) common reactions of those who work with rape victims; (4) the rape trauma syndrome; (5) an approach to immediate and short-term treatment; and (6) the long-term effects of sexual assault and related treatment issues.

  18. An investigation into pilot and system response to critical in-flight events. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Rockwell, T. H.; Griffin, W. C.

    1981-01-01

    Critical in-flight events (CIFE) that threaten the aircraft were studied. The scope of the CIFE was described and defined with emphasis on characterizing event development, detection and assessment; pilot information requirements, sources, acquisition, and interpretation, pilot response options, decision processed, and decision implementation and event outcome. Detailed scenarios were developed for use in simulators and paper and pencil testing for developing relationships between pilot performance and background information as well as for an analysis of pilot reaction decision and feedback processes. Statistical relationships among pilot characteristics and observed responses to CIFE's were developed.

  19. Fe-Catalyzed C–C Bond Construction from Olefins via Radicals

    PubMed Central

    2017-01-01

    This Article details the development of the iron-catalyzed conversion of olefins to radicals and their subsequent use in the construction of C–C bonds. Optimization of a reductive diene cyclization led to the development of an intermolecular cross-coupling of electronically-differentiated donor and acceptor olefins. Although the substitution on the donor olefins was initially limited to alkyl and aryl groups, additional efforts culminated in the expansion of the scope of the substitution to various heteroatom-based functionalities, providing a unified olefin reactivity. A vinyl sulfone acceptor olefin was developed, which allowed for the efficient synthesis of sulfone adducts that could be used as branch points for further diversification. Moreover, this reactivity was extended into an olefin-based Minisci reaction to functionalize heterocyclic scaffolds. Finally, mechanistic studies resulted in a more thorough understanding of the reaction, giving rise to the development of a more efficient second-generation set of olefin cross-coupling conditions. PMID:28094980

  20. The photocatalyzed Meerwein arylation: classic reaction of aryl diazonium salts in a new light.

    PubMed

    Hari, Durga Prasad; König, Burkhard

    2013-04-26

    The use of diazonium salts for aryl radical generation and C-H arylation processes has been known since 1896 when Pschorr first used the reaction for intramolecular cyclizations. Meerwein developed it further in the early 1900s into a general arylation method. However, this reaction could not compete with the transition-metal-mediated formation of C(sp(2))-C(sp(2)) bonds. The replacement of the copper catalyst with iron and titanium compounds improved the situation, but the use of photocatalysis to induce the one-electron reduction and activation of the diazonium salts is even more advantageous. The first photocatalyzed Pschorr cyclization was published in 1984, and just last year a series of papers described applications of photocatalytic Meerwein arylations leading to aryl-alkene coupling products. In this Minireview we summarize the origins of this reaction and its scope and applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Development of interactive graphic user interfaces for modeling reaction-based biogeochemical processes in batch systems with BIOGEOCHEM

    NASA Astrophysics Data System (ADS)

    Chang, C.; Li, M.; Yeh, G.

    2010-12-01

    The BIOGEOCHEM numerical model (Yeh and Fang, 2002; Fang et al., 2003) was developed with FORTRAN for simulating reaction-based geochemical and biochemical processes with mixed equilibrium and kinetic reactions in batch systems. A complete suite of reactions including aqueous complexation, adsorption/desorption, ion-exchange, redox, precipitation/dissolution, acid-base reactions, and microbial mediated reactions were embodied in this unique modeling tool. Any reaction can be treated as fast/equilibrium or slow/kinetic reaction. An equilibrium reaction is modeled with an implicit finite rate governed by a mass action equilibrium equation or by a user-specified algebraic equation. A kinetic reaction is modeled with an explicit finite rate with an elementary rate, microbial mediated enzymatic kinetics, or a user-specified rate equation. None of the existing models has encompassed this wide array of scopes. To ease the input/output learning curve using the unique feature of BIOGEOCHEM, an interactive graphic user interface was developed with the Microsoft Visual Studio and .Net tools. Several user-friendly features, such as pop-up help windows, typo warning messages, and on-screen input hints, were implemented, which are robust. All input data can be real-time viewed and automated to conform with the input file format of BIOGEOCHEM. A post-processor for graphic visualizations of simulated results was also embedded for immediate demonstrations. By following data input windows step by step, errorless BIOGEOCHEM input files can be created even if users have little prior experiences in FORTRAN. With this user-friendly interface, the time effort to conduct simulations with BIOGEOCHEM can be greatly reduced.

  2. Solid-phase organic synthesis of difluoroalkyl entities using a novel fluorinating cleavage strategy: part 1. Linker development: scope and limitations.

    PubMed

    Wiehn, Matthias S; Lindell, Stephen D; Bräse, Stefan

    2009-01-01

    An efficient method to synthesize gem-difluorinated compounds on solid supports is described. The strategy is based on the design of a novel sulfur linker system that enables, to the best of our knowledge for the first time, the release of target structures from the resin under simultaneous fluorination. Starting from an immobilized dithiol, coupling with an excess of aldehyde or ketone furnished dithianes. These can be further functionalized prior to release from the resin using our newly developed fluorinating cleavage conditions. Amide forming reactions, palladium-catalyzed reactions (Heck, Suzuki, and Sonogashira couplings), reductions, alkylations, and olefinations were successfully explored on the linker. The difluorinated target substances were obtained in modest to excellent yields and in high purities.

  3. Protected Chloroethyl and Chloropropyl Amines as Conformationally Unrestricted Annulating Reagents.

    PubMed

    Shi, Qing; Meehan, Mariah C; Galella, Michael; Park, Hyunsoo; Khandelwal, Purnima; Hynes, John; Dhar, T G Murali; Marcoux, David

    2018-01-19

    The purpose of this letter is to document the use of protected chloroethyl and chloropropyl amines as conformationally unrestricted ambiphilic reagents that undergo annulation reactions with Michael acceptors. This reaction is wide in scope and utilizes reagents that are commercially available, inexpensive, and stable. Furthermore, this reaction is easy to execute and proceeds rapidly.

  4. MICROWAVE EFFECTS IN ORGANIC SYNTHESIS: MECHANISTIC AND REACTION MEDIUM CONSIDERATIONS

    EPA Science Inventory

    The scope of applications of microwave irradiation relates to a wide spectrum of organic syntheses with numerous benefits (reduction in reaction times, improved purity of products and better yields) encompassing advantages of both thermal and (or) specific non-purely thermal effe...

  5. The Pd-Catalyzed Conversion of Aryl Chlorides, Triflates, and Nonaflates to Nitroaromatics

    PubMed Central

    Fors, Brett P.; Buchwald, Stephen L.

    2009-01-01

    An efficient Pd-catalyst for the transformation of aryl chlorides, triflates and nonaflates to nitroaromatics has been developed. This reaction proceeds under weekly basic conditions and displays a broad scope and excellent functional group compatibility. Moreover, this method allows for the synthesis of aromatic nitro compounds that cannot be accessed efficiently via other nitration protocols. Mechanistic insight into the trasmetallation step of the catalytic process is also reported. PMID:19737014

  6. Monolith catalysts for closed-cycle carbon dioxide lasers

    NASA Technical Reports Server (NTRS)

    Herz, Richard K.

    1994-01-01

    The general subject area of the project involved the development of solid catalysts that have high activity at low temperature for the oxidation of gases such as CO. The original application considered was CO oxidation in closed-cycle CO2 lasers. The scope of the project was subsequently extended to include oxidation of gases in addition to CO and applications such as air purification and exhaust gas emission control. The primary objective of the final phase grant was to develop design criteria for the formulation of new low-temperature oxidation catalysts utilizing Monte Carlo simulations of reaction over NASA-developed catalysts.

  7. Light-Induced C-H Arylation of (Hetero)arenes by In Situ Generated Diazo Anhydrides.

    PubMed

    Cantillo, David; Mateos, Carlos; Rincon, Juan A; de Frutos, Oscar; Kappe, C Oliver

    2015-09-07

    Diazo anhydrides (Ar-N=N-O-N=N-Ar) have been known since 1896 but have rarely been used in synthesis. This communication describes the development of a photochemical catalyst-free C-H arylation methodology for the preparation of bi(hetero)aryls by the one-pot reaction of anilines with tert-butyl nitrite and (hetero)arenes under neutral conditions. The key step in this procedure is the in situ formation and subsequent photochemical (>300 nm) homolytic cleavage of a transient diazo anhydride intermediate. The generated aryl radical then efficiently reacts with a (hetero)arene to form the desired bi(hetero)aryls producing only nitrogen, water, and tert-butanol as byproducts. The scope of the reaction for several substituted anilines and (hetero)arenes was investigated. A continuous-flow protocol increasing selectivity and safety has been developed enabling the experimentally straightforward preparation of a variety of substituted bi(hetero)aryls within 45 min of reaction time. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Scope and mechanism of the highly stereoselective metal-mediated domino aldol reactions of enolates with aldehydes

    PubMed Central

    Engelen, Bernward; Panthöfer, Martin; Deiseroth, Hans-Jörg; Schlirf, Jens

    2016-01-01

    Summary A one-pot transformation, which involves the reaction of ketones with aldehydes in the presence of metal halides to furnish tetrahydro-2H-pyran-2,4-diols in a highly diastereoselective manner, is investigated thoroughly by experiments and computations. The reaction was also successfully implemented on a flow micro reactor system. PMID:27340472

  9. Diastereoselective intermolecular Pauson-Khand reactions of chiral cyclopropenes.

    PubMed

    Pallerla, Mahesh K; Fox, Joseph M

    2005-08-04

    In this Letter, it is demonstrated that the unusual reactivity of cyclopropenes can increase the scope and utility of intermolecular Pauson-Khand reactions. The well-defined chiral environment of cyclopropenes has a powerful influence on the diastereoselectivity of the reactions and leads to the production of a single cyclopentenone in each of the described cases. The cyclopropane ring strongly influences the stereochemistry of reactions at the enone, and the three-membered ring can subsequently be cleaved under mild conditions. [reaction: see text

  10. Acute stress responses: A review and synthesis of ASD, ASR, and CSR.

    PubMed

    Isserlin, Leanna; Zerach, Gadi; Solomon, Zahava

    2008-10-01

    Toward the development of a unifying diagnosis for acute stress responses this article attempts to find a place for combat stress reaction (CSR) within the spectrum of other defined acute stress responses. This article critically compares the diagnostic criteria of acute stress disorder (ASD), acute stress reaction (ASR), and CSR. Prospective studies concerning the predictive value of ASD, ASR, and CSR are reviewed. Questions, recommendations, and implications for clinical practice are raised concerning the completeness of the current acute stress response diagnoses, the heterogeneity of different stressors, the scope of expected outcomes, and the importance of decline in function as an indicator of future psychological, psychiatric, and somatic distress. PsycINFO Database Record 2009 APA.

  11. Practical synthesis of phthalimides and benzamides by a multicomponent reaction involving arynes, isocyanides, and CO2/H2O.

    PubMed

    Kaicharla, Trinadh; Thangaraj, Manikandan; Biju, Akkattu T

    2014-03-21

    Transition-metal-free multicomponent reactions involving arynes and isocyanides with either CO2 or H2O have been reported. With CO2 as the third component, the reactions resulted in the formation of N-substituted phthalimides. The utility of water as the third component furnished benzamide derivatives in moderate to good yields. These reactions took place under mild conditions with broad scope.

  12. Chemoselective N-heterocyclic carbene-catalyzed cross-benzoin reactions: importance of the fused ring in triazolium salts.

    PubMed

    Langdon, Steven M; Wilde, Myron M D; Thai, Karen; Gravel, Michel

    2014-05-28

    Morpholinone- and piperidinone-derived triazolium salts are shown to catalyze highly chemoselective cross-benzoin reactions between aliphatic and aromatic aldehydes. The reaction scope includes ortho-, meta-, and para-substituted benzaldehyde derivatives with a range of electron-donating and -withdrawing groups as well as branched and unbranched aliphatic aldehydes. Catalytic loadings as low as 5 mol % give excellent yields in these reactions (up to 99%).

  13. The Domino Way to Heterocycles

    PubMed Central

    Padwa, Albert; Bur, Scott K.

    2007-01-01

    Sequential transformations enable the facile synthesis of complex target molecules from simple building blocks in a single preparative step. Their value is amplified if they also create multiple stereogenic centers. In the ongoing search for new domino processes, emphasis is usually placed on sequential reactions which occur cleanly and without forming by-products. As a prerequisite for an ideally proceeding one-pot sequential transformation, the reactivity pattern of all participating components has to be such that each building block gets involved in a reaction only when it is supposed to do so. The development of sequences that combine transformations of fundamentally different mechanisms broadens the scope of such procedures in synthetic chemistry. This mini review contains a representative sampling from the last 15 years on the kinds of reactions that have been sequenced into cascades to produce heterocyclic molecules. PMID:17940591

  14. Automating gene library synthesis by structure-based combinatorial protein engineering: examples from plant sesquiterpene synthases.

    PubMed

    Dokarry, Melissa; Laurendon, Caroline; O'Maille, Paul E

    2012-01-01

    Structure-based combinatorial protein engineering (SCOPE) is a homology-independent recombination method to create multiple crossover gene libraries by assembling defined combinations of structural elements ranging from single mutations to domains of protein structure. SCOPE was originally inspired by DNA shuffling, which mimics recombination during meiosis, where mutations from parental genes are "shuffled" to create novel combinations in the resulting progeny. DNA shuffling utilizes sequence identity between parental genes to mediate template-switching events (the annealing and extension of one parental gene fragment on another) in PCR reassembly reactions to generate crossovers and hence recombination between parental genes. In light of the conservation of protein structure and degeneracy of sequence, SCOPE was developed to enable the "shuffling" of distantly related genes with no requirement for sequence identity. The central principle involves the use of oligonucleotides to encode for crossover regions to choreograph template-switching events during PCR assembly of gene fragments to create chimeric genes. This approach was initially developed to create libraries of hybrid DNA polymerases from distantly related parents, and later developed to create a combinatorial mutant library of sesquiterpene synthases to explore the catalytic landscapes underlying the functional divergence of related enzymes. This chapter presents a simplified protocol of SCOPE that can be integrated with different mutagenesis techniques and is suitable for automation by liquid-handling robots. Two examples are presented to illustrate the application of SCOPE to create gene libraries using plant sesquiterpene synthases as the model system. In the first example, we outline how to create an active-site library as a series of complex mixtures of diverse mutants. In the second example, we outline how to create a focused library as an array of individual clones to distil minimal combinations of functionally important mutations. Through these examples, the principles of the technique are illustrated and the suitability of automating various aspects of the procedure for given applications are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Palladium-catalysed electrophilic aromatic C-H fluorination

    NASA Astrophysics Data System (ADS)

    Yamamoto, Kumiko; Li, Jiakun; Garber, Jeffrey A. O.; Rolfes, Julian D.; Boursalian, Gregory B.; Borghs, Jannik C.; Genicot, Christophe; Jacq, Jérôme; van Gastel, Maurice; Neese, Frank; Ritter, Tobias

    2018-02-01

    Aryl fluorides are widely used in the pharmaceutical and agrochemical industries, and recent advances have enabled their synthesis through the conversion of various functional groups. However, there is a lack of general methods for direct aromatic carbon-hydrogen (C-H) fluorination. Conventional methods require the use of either strong fluorinating reagents, which are often unselective and difficult to handle, such as elemental fluorine, or less reactive reagents that attack only the most activated arenes, which reduces the substrate scope. A method for the direct fluorination of aromatic C-H bonds could facilitate access to fluorinated derivatives of functional molecules that would otherwise be difficult to produce. For example, drug candidates with improved properties, such as increased metabolic stability or better blood-brain-barrier penetration, may become available. Here we describe an approach to catalysis and the resulting development of an undirected, palladium-catalysed method for aromatic C-H fluorination using mild electrophilic fluorinating reagents. The reaction involves a mode of catalysis that is unusual in aromatic C-H functionalization because no organometallic intermediate is formed; instead, a reactive transition-metal-fluoride electrophile is generated catalytically for the fluorination of arenes that do not otherwise react with mild fluorinating reagents. The scope and functional-group tolerance of this reaction could provide access to functional fluorinated molecules in pharmaceutical and agrochemical development that would otherwise not be readily accessible.

  16. Development of Selective Colorimetric Probes for Hydrogen Sulfide Based on Nucleophilic Aromatic Substitution

    PubMed Central

    Montoya, Leticia A.; Pearce, Taylor F.; Hansen, Ryan J.; Zakharov, Lev N.; Pluth, Michael D.

    2013-01-01

    Hydrogen sulfide is an important biological signalling molecule and an important environmental target for detection. A major challenge in developing H2S detection methods is separating the often similar reactivity of thiols and other nucleophiles from H2S. To address this need, the nucleophilic aromatic substitution (SNAr) reaction of H2S with electron-poor aromatic electrophiles was developed as a strategy to separate H2S and thiol reactivity. Treatment of aqueous solutions of nitrobenzofurazan (7-nitro-1,2,3-benzoxadiazole, NBD) thioethers with H2S resulted in thiol extrusion and formation of nitrobenzofurazan thiol (λmax = 534 nm). This reactivity allows for unwanted thioether products to be converted to the desired nitrobenzofurazan thiol upon reaction with H2S. The scope of the reaction was investigated using a Hammett linear free energy relationship study, and the determined ρ = +0.34 is consistent with the proposed SN2Ar reaction mechanism. The efficacy of the developed probes was demonstrated in buffer and in serum with associated sub-micromolar detection limits as low as 190 nM (buffer) and 380 nM (serum). Furthermore, the sigmoidal response of nitrobenzofurazan electrophiles with H2S can be fit to accurately quantify H2S. The developed detection strategy offers a manifold for H2S detection that we foresee being applied in various future applications. PMID:23735055

  17. Development of selective colorimetric probes for hydrogen sulfide based on nucleophilic aromatic substitution.

    PubMed

    Montoya, Leticia A; Pearce, Taylor F; Hansen, Ryan J; Zakharov, Lev N; Pluth, Michael D

    2013-07-05

    Hydrogen sulfide is an important biological signaling molecule and an important environmental target for detection. A major challenge in developing H2S detection methods is separating the often similar reactivity of thiols and other nucleophiles from H2S. To address this need, the nucleophilic aromatic substitution (SNAr) reaction of H2S with electron-poor aromatic electrophiles was developed as a strategy to separate H2S and thiol reactivity. Treatment of aqueous solutions of nitrobenzofurazan (7-nitro-1,2,3-benzoxadiazole, NBD) thioethers with H2S resulted in thiol extrusion and formation of nitrobenzofurazan thiol (λmax = 534 nm). This reactivity allows for unwanted thioether products to be converted to the desired nitrobenzofurazan thiol upon reaction with H2S. The scope of the reaction was investigated using a Hammett linear free energy relationship study, and the determined ρ = +0.34 is consistent with the proposed SN2Ar reaction mechanism. The efficacy of the developed probes was demonstrated in buffer and in serum with associated submicromolar detection limits as low as 190 nM (buffer) and 380 nM (serum). Furthermore, the sigmoidal response of nitrobenzofurazan electrophiles with H2S can be fit to accurately quantify H2S. The developed detection strategy offers a manifold for H2S detection that we foresee being applied in various future applications.

  18. An efficient synthesis of symmetric and unsymmetric bis-(β-aminoamides) via Ugi multicomponent reaction.

    PubMed

    La Spisa, Fabio; Feo, Alberto; Mossetti, Riccardo; Tron, Gian Cesare

    2012-12-07

    A library of symmetrical and unsymmetrical bis-(β-aminoamides) has been prepared starting from symmetrical secondary diamines by using a double Ugi four-component reaction. A sacrifical Mumm rearrangement, thanks to the use of 2-hydroxymethyl benzoic acid, is necessary to suppress the competing split-Ugi reaction, increasing the yield and simplifying the purification step. The scope, the reaction conditions, and the role of water in trapping the nitrilium intermediate are also discussed.

  19. Recent Advances in the Pauson-Khand Reaction.

    PubMed

    Ricker, J David; Geary, Laina M

    2017-06-01

    The Pauson-Khand [2+2+1] cycloaddition of alkynes, alkenes, and carbon monoxide has been a vibrant area of research for more than 40 years. This review highlights recent achievements in the Pauson-Khand reaction, particularly in catalytic and asymmetric variants. Discussion of regioselectivity and advances in substrate scope is also presented.

  20. Beyond D-luciferin: Expanding the Scope of Bioluminescence Imaging in vivo

    PubMed Central

    Adams, Spencer T.; Miller, Stephen C.

    2014-01-01

    The light-emitting chemical reaction catalyzed by the enzyme firefly luciferase is widely used for noninvasive imaging in live mice. However, photon emission from the luciferase is critically dependent on the chemical properties of its substrate, D-luciferin. In this review, we describe recent work to replace the natural luciferase substrate with synthetic analogs that extend the scope of bioluminescence imaging. PMID:25078002

  1. A general approach to intermolecular carbonylation of arene C-H bonds to ketones through catalytic aroyl triflate formation

    NASA Astrophysics Data System (ADS)

    Garrison Kinney, R.; Tjutrins, Jevgenijs; Torres, Gerardo M.; Liu, Nina Jiabao; Kulkarni, Omkar; Arndtsen, Bruce A.

    2018-02-01

    The development of metal-catalysed methods to functionalize inert C-H bonds has become a dominant research theme in the past decade as an approach to efficient synthesis. However, the incorporation of carbon monoxide into such reactions to form valuable ketones has to date proved a challenge, despite its potential as a straightforward and green alternative to Friedel-Crafts reactions. Here we describe a new approach to palladium-catalysed C-H bond functionalization in which carbon monoxide is used to drive the generation of high-energy electrophiles. This offers a method to couple the useful features of metal-catalysed C-H functionalization (stable and available reagents) and electrophilic acylations (broad scope and selectivity), and synthesize ketones simply from aryl iodides, CO and arenes. Notably, the reaction proceeds in an intermolecular fashion, without directing groups and at very low palladium-catalyst loadings. Mechanistic studies show that the reaction proceeds through the catalytic build-up of potent aroyl triflate electrophiles.

  2. A Conceptual Framework for Pharmacodynamic Genome-wide Association Studies in Pharmacogenomics

    PubMed Central

    Wu, Rongling; Tong, Chunfa; Wang, Zhong; Mauger, David; Tantisira, Kelan; Szefler, Stanley J.; Chinchilli, Vernon M.; Israel, Elliot

    2013-01-01

    Summary Genome-wide association studies (GWAS) have emerged as a powerful tool to identify loci that affect drug response or susceptibility to adverse drug reactions. However, current GWAS based on a simple analysis of associations between genotype and phenotype ignores the biochemical reactions of drug response, thus limiting the scope of inference about its genetic architecture. To facilitate the inference of GWAS in pharmacogenomics, we sought to undertake the mathematical integration of the pharmacodynamic process of drug reactions through computational models. By estimating and testing the genetic control of pharmacodynamic and pharmacokinetic parameters, this mechanistic approach does not only enhance the biological and clinical relevance of significant genetic associations, but also improve the statistical power and robustness of gene detection. This report discusses the general principle and development of pharmacodynamics-based GWAS, highlights the practical use of this approach in addressing various pharmacogenomic problems, and suggests that this approach will be an important method to study the genetic architecture of drug responses or reactions. PMID:21920452

  3. N719 dye-sensitized organophotocatalysis: enantioselective tandem Michael addition/oxyamination of aldehydes.

    PubMed

    Yoon, Hyo-Sang; Ho, Xuan-Huong; Jang, Jiyeon; Lee, Hwa-Jung; Kim, Seung-Joo; Jang, Hye-Young

    2012-07-06

    A remarkably efficient photosensitizer, N719 dye, was used in asymmetric tandem Michael addition/oxyamination of aldehydes, rendering α,β-substituted aldehydes in good yields with excellent levels of enantioselectivity and diastereoselectivity. This is the first report of a multiorganocatalytic reaction involving iminium catalysis and photoinduced singly occupied molecular orbital (SOMO) catalysis. This reaction is expected to expand the scope of tandem organocatalytic reactions.

  4. Direct asymmetric aldol reactions between aldehydes and ketones catalyzed by L-tryptophan in the presence of water.

    PubMed

    Jiang, Zhaoqin; Yang, Hui; Han, Xiao; Luo, Jie; Wong, Ming Wah; Lu, Yixin

    2010-03-21

    Primary amino acids and their derivatives were investigated as catalysts for the direct asymmetric aldol reactions between ketones and aldehydes in the presence of water, and L-tryptophan was shown to be the best catalyst. Solvent effects, substrate scope and the influence of water on the reactions were investigated. Quantum chemical calculations were performed to understand the origin of the observed stereoselectivity.

  5. Contributions to the NUCLEI SciDAC-3 Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bogner, Scott; Nazarewicz, Witek

    This is the Final Report for Michigan State University for the NUCLEI SciDAC-3 project. The NUCLEI project, as defined by the scope of work, has developed, implemented and run codes for large-scale computations of many topics in low-energy nuclear physics. Physics studied included the properties of nuclei and nuclear decays, nuclear structure and reactions, and the properties of nuclear matter. The computational techniques used included Configuration Interaction, Coupled Cluster, and Density Functional methods. The research program emphasized areas of high interest to current and possible future DOE nuclear physics facilities, including ATLAS at ANL and FRIB at MSU (nuclear structuremore » and reactions, and nuclear astrophysics), TJNAF (neutron distributions in nuclei, few body systems, and electroweak processes), NIF (thermonuclear reactions), MAJORANA and FNPB (neutrinoless double-beta decay and physics beyond the Standard Model), and LANSCE (fission studies).« less

  6. Nuclear Computational Low Energy Initiative (NUCLEI)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reddy, Sanjay K.

    This is the final report for University of Washington for the NUCLEI SciDAC-3. The NUCLEI -project, as defined by the scope of work, will develop, implement and run codes for large-scale computations of many topics in low-energy nuclear physics. Physics to be studied include the properties of nuclei and nuclear decays, nuclear structure and reactions, and the properties of nuclear matter. The computational techniques to be used include Quantum Monte Carlo, Configuration Interaction, Coupled Cluster, and Density Functional methods. The research program will emphasize areas of high interest to current and possible future DOE nuclear physics facilities, including ATLAS andmore » FRIB (nuclear structure and reactions, and nuclear astrophysics), TJNAF (neutron distributions in nuclei, few body systems, and electroweak processes), NIF (thermonuclear reactions), MAJORANA and FNPB (neutrino-less double-beta decay and physics beyond the Standard Model), and LANSCE (fission studies).« less

  7. Hierarchical thinking in network biology: the unbiased modularization of biochemical networks.

    PubMed

    Papin, Jason A; Reed, Jennifer L; Palsson, Bernhard O

    2004-12-01

    As reconstructed biochemical reaction networks continue to grow in size and scope, there is a growing need to describe the functional modules within them. Such modules facilitate the study of biological processes by deconstructing complex biological networks into conceptually simple entities. The definition of network modules is often based on intuitive reasoning. As an alternative, methods are being developed for defining biochemical network modules in an unbiased fashion. These unbiased network modules are mathematically derived from the structure of the whole network under consideration.

  8. Viability of a [2 + 2 + 1] Hetero-Pauson-Khand Cycloaddition Strategy toward Securinega Alkaloids: Synthesis of the BCD-Ring Core of Securinine and Related Alkaloids.

    PubMed

    Chirkin, Egor; Michel, Sylvie; Porée, François-Hugues

    2015-07-02

    Preliminary results related to the development of [2 + 2 + 1]-oxa-hetero-Pauson-Khand cycloaddition strategy toward the Securinega alkaloids are reported. The critical tricyclic BCD-ring core was assembled in only nine linear steps from cheap 4-hydroxy-l-proline. The study provides valuable insight into the scope of a rare hetero-Pauson-Khand reaction, a powerful tool for the rapid construction of butenolide-containing natural products.

  9. Iron-catalyzed 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes.

    PubMed

    Xu, Tao; Cheung, Chi Wai; Hu, Xile

    2014-05-05

    Iron catalysis has been developed for the intermolecular 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes. The catalysis has a wide substrate scope and high functional-group tolerance. A variety of perfluoroalkyl iodides including CF3 I can be employed. The resulting perfluoroalkylated alkyl and alkenyl iodides can be further functionalized by cross-coupling reactions. This methodology provides a straightforward and streamlined access to perfluoroalkylated organic molecules. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. State-of-the-art MS technology applications in lung disease.

    PubMed

    Végvári, Ákos; Döme, Balázs

    2011-12-01

    Two frontline MS technologies, which have recently gained much attention, are discussed within the scope of this review. Besides a brief summary on the contemporary state of lung cancer and chronic obstructive pulmonary disease, the principles of multiple reaction monitoring and matrix assisted laser desorption ionization (MALDI) MS imaging are presented. A comprehensive overview of quantitative mass spectrometry applications is provided, covering multiple reaction monitoring assay developments for analysis of proteins (biomarkers) and low-molecular-weight compounds (drugs) with a special focus on the disease areas of lung cancer and chronic obstructive pulmonary disease. The MALDI-MS imaging applications are discussed similarly, providing references to studies conducted on lung tissues in order to localize drug compounds and protein biomarkers.

  11. Towards mild metal-catalyzed C-H bond activation.

    PubMed

    Wencel-Delord, Joanna; Dröge, Thomas; Liu, Fan; Glorius, Frank

    2011-09-01

    Functionalizing traditionally inert carbon-hydrogen bonds represents a powerful transformation in organic synthesis, providing new entries to valuable structural motifs and improving the overall synthetic efficiency. C-H bond activation, however, often necessitates harsh reaction conditions that result in functional group incompatibilities and limited substrate scope. An understanding of the reaction mechanism and rational design of experimental conditions have led to significant improvement in both selectivity and applicability. This critical review summarizes and discusses endeavours towards the development of mild C-H activation methods and wishes to trigger more research towards this goal. In addition, we examine select examples in complex natural product synthesis to demonstrate the synthetic utility of mild C-H functionalization (84 references). This journal is © The Royal Society of Chemistry 2011

  12. Carboxylic acid reductase enzymes (CARs).

    PubMed

    Winkler, Margit

    2018-04-01

    Carboxylate reductases (CARs) are emerging as valuable catalysts for the selective one-step reduction of carboxylic acids to their corresponding aldehydes. The substrate scope of CARs is exceptionally broad and offers potential for their application in diverse synthetic processes. Two major fields of application are the preparation of aldehydes as end products for the flavor and fragrance sector and the integration of CARs in cascade reactions with aldehydes as the key intermediates. The latest applications of CARs are dominated by in vivo cascades and chemo-enzymatic reaction sequences. The challenge to fully exploit product selectivity is discussed. Recent developments in the characterization of CARs are summarized, with a focus on aspects related to the domain architecture and protein sequences of CAR enzymes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 29 CFR 1910.155 - Scope, application and definitions applicable to this subpart.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... by inhibiting the chemical chain reaction of fuel and oxygen. It is also known as...F3) which is a medium for extinguishing fires by inhibiting the chemical chain reaction of fuel and..., odorless, electrically nonconductive inert gas (chemical formula CO2) that is a medium for extinguishing...

  14. Cyanine polyene reactivity: scope and biomedical applications | Center for Cancer Research

    Cancer.gov

    Cyanines are indispensable fluorophores that form the chemical basis of many fluorescence-based applications. A feature that distinguishes cyanines from other common fluorophores is an exposed polyene linker that is both crucial to absorption and emission and subject to covalent reactions that dramatically alter these optical properties. Over the past decade, reactions

  15. Evolution of Instrumentation for the Study of Gas-Phase Ion/Ion Chemistry via Mass Spectrometry

    PubMed Central

    Xia, Yu; McLuckey, Scott A.

    2008-01-01

    The scope of gas phase ion/ion chemistry accessible to mass spectrometry is largely defined by the available tools. Due to the development of novel instrumentation, a wide range of reaction phenomenologies have been noted, many of which have been studied extensively and exploited for analytical applications. This perspective presents the development of mass spectrometry-based instrumentation for the study of the gas phase ion/ion chemistry in which at least one of the reactants is multiply-charged. The instrument evolution is presented within the context of three essential elements required for any ion/ion reaction study: the ionization source(s), the reaction vessel or environment, and the mass analyzer. Ionization source arrangements have included source combinations that allow for reactions between multiply charged ions of one polarity and singly charged ions of opposite polarity, arrangements that enable the study of reactions of multiply charged ions of opposite polarity, and most recently, arrangements that allow for ion formation from more than two ion sources. Gas phase ion/ion reaction studies have been performed at near atmospheric pressure in flow reactor designs and within electrodynamic ion traps operated in the mTorr range. With ion trap as a reaction vessel, ionization and reaction processes can be independently optimized and ion/ion reactions can be implemented within the context of MSn experiments. Spatial separation of the reaction vessel from the mass analyzer allows for the use of any form of mass analysis in conjunction with ion/ion reactions. Time-of-flight mass analysis, for example, has provided significant improvements in mass analysis figures of merit relative to mass filters and ion traps. PMID:18083527

  16. Copper-Catalyzed γ-Selective and Stereospecific Allylic Cross-Coupling with Secondary Alkylboranes.

    PubMed

    Yasuda, Yuto; Nagao, Kazunori; Shido, Yoshinori; Mori, Seiji; Ohmiya, Hirohisa; Sawamura, Masaya

    2015-06-26

    The scope of the copper-catalyzed coupling reactions between organoboron compounds and allylic phosphates is expanded significantly by employing triphenylphosphine as a ligand for copper, allowing the use of secondary alkylboron compounds. The reaction proceeds with complete γ-E-selectivity and preferential 1,3-syn stereoselectivity. The reaction of γ-silicon-substituted allylic phosphates affords enantioenriched α-stereogenic allylsilanes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Diastereoselective radical addition to γ-alkyl-α-methylene-γ-butyrolactams and the synthesis of a chiral pyroglutamic acid derivative.

    PubMed

    Yajima, Tomoko; Yoshida, Eriko; Hamano, Masako

    2013-01-01

    The cis- and trans-stereoselective radical additions to α-methylene-γ-alkyl- γ-lactams were investigated and the scope and limitation of the reaction were also revealed. This stereoselective radical reaction was used for synthesis of chiral pyroglutamic acid derivatives starting from a commercially available chiral amino acid.

  18. Dicobalt hexacarbonyl complexes of alkynyl imines in a sequential Staudinger/Pauson-Khand process. A route to new fused tricyclic beta-lactams.

    PubMed

    Olier, Clarisse; Azzi, Nadia; Gil, Gérard; Gastaldi, Stéphane; Bertrand, Michèle P

    2008-11-07

    Dicobalt hexacarbonyl complexes of alkynyl imines were allowed to react with ketenes via Staudinger reaction. Sequential [2 + 2] cycloaddition/Pauson-Khand reaction led to structurally new fused-tricyclic beta-lactams and fused-azabicyclic cyclopentenones. Chemoselectivity, scope, and limitation of the process were investigated.

  19. Recent advances in transition metal-catalyzed N -atom transfer reactions of azides

    PubMed Central

    Driver, Tom G.

    2011-01-01

    Transition metal-catalyzed N-atom transfer reactions of azides provide efficient ways to construct new carbon–nitrogen and sulfur–nitrogen bonds. These reactions are inherently green: no additive besides catalyst is needed to form the nitrenoid reactive intermediate, and the by-product of the reaction is environmentally benign N2 gas. As such, azides can be useful precursors for transition metal-catalyzed N-atom transfer to sulfides, olefins and C–H bonds. These methods offer competitive selectivities and comparable substrate scope as alternative processes to generate metal nitrenoids. PMID:20617243

  20. Enantioselective addition of nitromethane to 2-acylpyridine N-oxides. Expanding the generation of quaternary stereocenters with the Henry reaction.

    PubMed

    Holmquist, Melireth; Blay, Gonzalo; Muñoz, M Carmen; Pedro, José R

    2014-02-21

    The direct asymmetric Henry reaction with prochiral ketones, leading to tertiary nitroaldols, is an elusive reaction so far limited to a reduced number of reactive substrates such as trifluoromethyl ketones or α-keto carbonyl compounds. Expanding the scope of this important reaction, the direct asymmetric addition of nitromethane to 2-acylpyridine N-oxides catalyzed by a BOX-Cu(II) complex to give the corresponding pyridine-derived tertiary nitroaldols having a quaternary stereogenic center with variable yields and good enantioselectivity, is described.

  1. Rhodium-catalyzed Intra- and Intermolecular [5+2] Cycloaddition of 3-Acyloxy-1,4-enyne and Alkyne with Concomitant 1,2-Acyloxy Migration

    PubMed Central

    Shu, Xing-Zhong; Li, Xiaoxun; Shu, Dongxu; Huang, Suyu; Schienebeck, Casi M.; Zhou, Xin; Robichaux, Patrick J.; Tang, Weiping

    2012-01-01

    A new type of rhodium-catalyzed [5+2] cycloaddition was developed for the synthesis of seven-membered rings with diverse functionalities. The ring formation was accompanied by a 1,2-acyloxy migration event. The 5- and 2-carbon components of the cycloaddition are 3-acyloxy-1,4-enynes (ACEs) and alkynes respectively. Cationic rhodium (I) catalysts worked most efficiently for the intramolecular cycloaddition, while only neutral rhodium (I) complexes could facilitate the intermolecular reaction. In both cases, electron-poor phosphite or phosphine ligands often improved the efficiency of the cycloadditions. The scope of ACEs and alkynes was investigated in both intra- and intermolecular reactions. The resulting seven-membered ring products have three double bonds that could be selectively functionalized. PMID:22364320

  2. Zea mays iRS1563: A Comprehensive Genome-Scale Metabolic Reconstruction of Maize Metabolism

    PubMed Central

    Saha, Rajib; Suthers, Patrick F.; Maranas, Costas D.

    2011-01-01

    The scope and breadth of genome-scale metabolic reconstructions have continued to expand over the last decade. Herein, we introduce a genome-scale model for a plant with direct applications to food and bioenergy production (i.e., maize). Maize annotation is still underway, which introduces significant challenges in the association of metabolic functions to genes. The developed model is designed to meet rigorous standards on gene-protein-reaction (GPR) associations, elementally and charged balanced reactions and a biomass reaction abstracting the relative contribution of all biomass constituents. The metabolic network contains 1,563 genes and 1,825 metabolites involved in 1,985 reactions from primary and secondary maize metabolism. For approximately 42% of the reactions direct literature evidence for the participation of the reaction in maize was found. As many as 445 reactions and 369 metabolites are unique to the maize model compared to the AraGEM model for A. thaliana. 674 metabolites and 893 reactions are present in Zea mays iRS1563 that are not accounted for in maize C4GEM. All reactions are elementally and charged balanced and localized into six different compartments (i.e., cytoplasm, mitochondrion, plastid, peroxisome, vacuole and extracellular). GPR associations are also established based on the functional annotation information and homology prediction accounting for monofunctional, multifunctional and multimeric proteins, isozymes and protein complexes. We describe results from performing flux balance analysis under different physiological conditions, (i.e., photosynthesis, photorespiration and respiration) of a C4 plant and also explore model predictions against experimental observations for two naturally occurring mutants (i.e., bm1 and bm3). The developed model corresponds to the largest and more complete to-date effort at cataloguing metabolism for a plant species. PMID:21755001

  3. Diastereoselective radical addition to γ-alkyl-α-methylene-γ-butyrolactams and the synthesis of a chiral pyroglutamic acid derivative

    PubMed Central

    Yoshida, Eriko; Hamano, Masako

    2013-01-01

    Summary The cis- and trans-stereoselective radical additions to α-methylene-γ-alkyl- γ-lactams were investigated and the scope and limitation of the reaction were also revealed. This stereoselective radical reaction was used for synthesis of chiral pyroglutamic acid derivatives starting from a commercially available chiral amino acid. PMID:23946839

  4. Access to Diosgenyl Glycoconjugates via Gold(I)-Catalyzed Etherification of Diosgen-3-yl ortho-Hexynylbenzoate.

    PubMed

    Zhang, Li; Li, Linfeng; Bai, Shujin; Zhou, Xin; Wang, Peng; Li, Ming

    2016-12-02

    An efficient protocol for the synthesis of diverse diosgen-3-yl glycoconjugates, a class of novel synthetic analogs of natural saponins of biological significance, has been developed. The method relies on gold(I)-catalyzed etherification of diosgen-3-yl ortho-hexynylbenzoate with stoichiometric sugar alcohols to afford the corresponding glycoconjugates in 38%-99% yields. The reaction involves the preferential attack of hydroxyl groups to the C3 position of homoallylic carbocation intermediate and displays a broad substrate scope and a good functional group tolerance.

  5. RNA catalysis and the origins of life

    NASA Technical Reports Server (NTRS)

    Orgel, Leslie E.

    1986-01-01

    The role of RNA catalysis in the origins of life is considered in connection with the discovery of riboszymes, which are RNA molecules that catalyze sequence-specific hydrolysis and transesterification reactions of RNA substrates. Due to this discovery, theories positing protein-free replication as preceding the appearance of the genetic code are more plausible. The scope of RNA catalysis in biology and chemistry is discussed, and it is noted that the development of methods to select (or predict) RNA sequences with preassigned catalytic functions would be a major contribution to the study of life's origins.

  6. The photochemical thiol–ene reaction as a versatile method for the synthesis of glutathione S-conjugates targeting the bacterial potassium efflux system Kef† †Electronic supplementary information (ESI) available: Further experimental details and NMR spectra. See DOI: 10.1039/c5qo00436e Click here for additional data file.

    PubMed Central

    Rasmussen, Tim; Miller, Samantha; Booth, Ian R.

    2016-01-01

    The thiol–ene coupling reaction is emerging as an important conjugation reaction that is suitable for use in a biological setting. Here, we explore the utility of this reaction for the synthesis of glutathione-S-conjugates (GSX) and present a general, operationally simple, protocol with a wide substrate scope. The GSX afforded are an important class of compounds and provide invaluable molecular tools to study glutathione-binding proteins. In this study we apply the diverse library of GSX synthesised to further our understanding of the structural requirements for binding to the glutathione-binding protein, Kef, a bacterial K+ efflux system, found in many bacterial pathogens. This system is vital to the survival of bacteria upon exposure to electrophiles, and plays an essential role in the maintenance of intracellular pH and K+ homeostasis. Consequently, Kef is an appealing target for the development of novel antibacterial drugs. PMID:27110363

  7. Artificial concurrent catalytic processes involving enzymes.

    PubMed

    Köhler, Valentin; Turner, Nicholas J

    2015-01-11

    The concurrent operation of multiple catalysts can lead to enhanced reaction features including (i) simultaneous linear multi-step transformations in a single reaction flask (ii) the control of intermediate equilibria (iii) stereoconvergent transformations (iv) rapid processing of labile reaction products. Enzymes occupy a prominent position for the development of such processes, due to their high potential compatibility with other biocatalysts. Genes for different enzymes can be co-expressed to reconstruct natural or construct artificial pathways and applied in the form of engineered whole cell biocatalysts to carry out complex transformations or, alternatively, the enzymes can be combined in vitro after isolation. Moreover, enzyme variants provide a wider substrate scope for a given reaction and often display altered selectivities and specificities. Man-made transition metal catalysts and engineered or artificial metalloenzymes also widen the range of reactivities and catalysed reactions that are potentially employable. Cascades for simultaneous cofactor or co-substrate regeneration or co-product removal are now firmly established. Many applications of more ambitious concurrent cascade catalysis are only just beginning to appear in the literature. The current review presents some of the most recent examples, with an emphasis on the combination of transition metal with enzymatic catalysis and aims to encourage researchers to contribute to this emerging field.

  8. Copper(II) carboxylate promoted intramolecular diamination of terminal alkenes: improved reaction conditions and expanded substrate scope.

    PubMed

    Zabawa, Thomas P; Chemler, Sherry R

    2007-05-10

    The copper(II) carboxylate promoted diamination reaction has been improved by the use of the organic soluble copper(II) neodecanoate [Cu(ND)2]. Cu(ND)2 allowed the less-polar solvent dichloroethane (DCE) to be used, and as a consequence, decomposition of less-reactive substrates could be avoided. High diastereoselectivity was observed in the synthesis of 2,5-disubstituted pyrrolidines. Ureas, bis(anilines), and alpha-amido pyrroles derived from 2-allylaniline could also participate in the diamination reaction.

  9. Copper-facilitated Suzuki reactions: application to 2-heterocyclic boronates.

    PubMed

    Deng, James Z; Paone, Daniel V; Ginnetti, Anthony T; Kurihara, Hideki; Dreher, Spencer D; Weissman, Steven A; Stauffer, Shaun R; Burgey, Christopher S

    2009-01-15

    The palladium-catalyzed Suzuki-Miyaura reaction has been utilized as one of the most powerful methods for C-C bond formation. However, Suzuki reactions of electron-deficient 2-heterocyclic boronates generally give low conversions and remain challenging. The successful copper(I) facilitated Suzuki coupling of 2-heterocyclic boronates that is broad in scope is reported. Use of this methodology affords greatly enhanced yields of these notoriously difficult couplings. Furthermore, mechanistic investigations suggest a possible role of copper in the catalytic cycle.

  10. Stereoselective Synthesis of Functionalized Bicyclic Scaffolds by Passerini 3-Center-2-Component Reactions of Cyclic Ketoacids.

    PubMed

    Cioc, Răzvan C; Estévez, Verónica; van der Niet, Daan J; Vande Velde, Christophe M L; Turrini, Nikolaus G; Hall, Mélanie; Faber, Kurt; Ruijter, Eelco; Orru, Romano V A

    2017-03-03

    We report the use of bifunctional starting materials (ketoacids) in a diastereoselective Passerini three-center-two-component reaction. Study of the reaction scope revealed the required structural features for stereoselectivity in the isocyanide addition. In this system, an interesting isomerization of the primary Passerini product - the α-carboxamido lactone - into an atypical product, an α-hydroxy imide, was found to occur under acidic conditions. Furthermore, enantioenriched Passerini products can be generated from an enantioenriched ketoacid obtained by chemoenzymatic synthesis.

  11. Continuous flow chemistry: a discovery tool for new chemical reactivity patterns.

    PubMed

    Hartwig, Jan; Metternich, Jan B; Nikbin, Nikzad; Kirschning, Andreas; Ley, Steven V

    2014-06-14

    Continuous flow chemistry as a process intensification tool is well known. However, its ability to enable chemists to perform reactions which are not possible in batch is less well studied or understood. Here we present an example, where a new reactivity pattern and extended reaction scope has been achieved by transferring a reaction from batch mode to flow. This new reactivity can be explained by suppressing back mixing and precise control of temperature in a flow reactor set up.

  12. Room temperature decarboxylative cyanation of carboxylic acids using photoredox catalysis and cyanobenziodoxolones: a divergent mechanism compared to alkynylation† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc04907a Click here for additional data file.

    PubMed Central

    Le Vaillant, Franck; Wodrich, Matthew D.

    2017-01-01

    The one-step conversion of aliphatic carboxylic acids to the corresponding nitriles has been accomplished via the merger of visible light mediated photoredox and cyanobenziodoxolones (CBX) reagents. The reaction proceeded in high yields with natural and non-natural α-amino and α-oxy acids, affording a broad scope of nitriles with excellent tolerance of the substituents in the α position. The direct cyanation of dipeptides and drug precursors was also achieved. The mechanism of the decarboxylative cyanation was investigated both computationally and experimentally and compared with the previously developed alkynylation reaction. Alkynylation was found to favor direct radical addition, whereas further oxidation by CBX to a carbocation and cyanide addition appeared more favorable for cyanation. A concerted mechanism is proposed for the reaction of radicals with EBX reagents, in contrast to the usually assumed addition elimination process. PMID:28451301

  13. Sulfur and Its Role In Modern Materials Science.

    PubMed

    Boyd, Darryl A

    2016-12-12

    Although well-known and studied for centuries, sulfur continues to be at the center of an extensive array of scientific research topics. As one of the most abundant elements in the Universe, a major by-product of oil refinery processes, and as a common reaction site within biological systems, research involving sulfur is both broad in scope and incredibly important to our daily lives. Indeed, there has been renewed interest in sulfur-based reactions in just the past ten years. Sulfur research spans the spectrum of topics within the physical sciences including research on improving energy efficiency, environmentally friendly uses for oil refinery waste products, development of polymers with unique optical and mechanical properties, and materials produced for biological applications. This Review focuses on some of the latest exciting ways in which sulfur and sulfur-based reactions are being utilized to produce materials for application in energy, environmental, and other practical areas. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Control of a chemical reaction (photodegradation of the p3ht polymer) with nonlocal dielectric environments

    PubMed Central

    Peters, V. N.; Tumkur, T. U.; Zhu, G.; Noginov, M. A.

    2015-01-01

    Proximity to metallic surfaces, plasmonic structures, cavities and other inhomogeneous dielectric environments is known to control spontaneous emission, energy transfer, scattering, and many other phenomena of practical importance. The aim of the present study was to demonstrate that, in spirit of the Marcus theory, the rates of chemical reactions can, too, be influenced by nonlocal dielectric environments, such as metallic films and metal/dielectric bilayer or multilayer structures. We have experimentally shown that metallic, composite metal/dielectric substrates can, indeed, control ordering as well as photodegradation of thin poly-3-hexylthiophene (p3ht) films. In many particular experiments, p3ht films were separated from metal by a dielectric spacer, excluding conventional catalysis facilitated by metals and making modification of the nonlocal dielectric environment a plausible explanation for the observed phenomena. This first step toward understanding of a complex relationship between chemical reactions and nonlocal dielectric environments is to be followed by the theory development and a broader scope of thorough experimental studies. PMID:26434679

  15. Rhodium/Silver-Cocatalyzed Transannulation of N-Sulfonyl-1,2,3-triazoles with Vinyl Azides: Divergent Synthesis of Pyrroles and 2 H-Pyrazines.

    PubMed

    Zhang, Lin; Sun, Ge; Bi, Xihe

    2016-11-07

    The first cyclization reaction between vinyl azides and N-sulfonyl-1,2,3-triazoles is reported. A Rh/Ag binary metal catalyst system proved to be necessary for the successful cyclization. By varying the structure of vinyl azides, such reaction allows the divergent synthesis of pyrroles and 2H-pyrazines. The cyclization reactions feature a broad substrate scope, good functional group tolerance, high reaction efficiency, and good to high product yields. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Studies on the Himbert Intramolecular Arene/ Allene Diels – Alder Cycloaddition. Mechanistic Studies and Expansion of Scope to All-Carbon Tethers

    PubMed Central

    Schmidt, Yvonne; Lam, Jonathan K.; Pham, Hung V.; Houk, K. N.; Vanderwal, Christopher D.

    2013-01-01

    The unusual intramolecular arene/allene cycloaddition described thirty years ago by Himbert permits rapid access to strained polycyclic compounds that offer great potential for the synthesis of complex scaffolds. To more fully understand the mechanism of this cycloaddition reaction, and to guide efforts to extend its scope to new substrates, quantum mechanical computational methods were employed in concert with laboratory experiments. These studies indicated that the cycloadditions likely proceed via concerted processes; a stepwise biradical mechanism was shown to be higher in energy in the cases studied. The original Himbert cycloaddition chemistry is also extended from heterocyclic to carbocyclic systems, with computational guidance used to predict thermodynamically favorable cases. Complex polycyclic scaffolds result from the combination of the cycloaddition and subsequent ring-rearrangement metathesis reactions. PMID:23634642

  17. Indium Triflate Catalyzed Peracetylation of Carbohydrates

    PubMed Central

    Bizier, Nicholas P.; Atkins, Shannon R.; Helland, Luke C.; Colvin, Shane F.; Twitchell, Joseph R.; Cloninger, Mary J.

    2008-01-01

    Peracetylation is a very common protection strategy that is widely implemented in carbohydrate synthesis. Here, a method for peracetylation of carbohydrates using catalytic In(OTf)3 in neat acetic anhydride is reported. In(OTf)3 has low toxicity and is mild and water tolerant, and the reactions are high yielding and efficient. Details regarding the scope and mechanism of the reaction are briefly discussed. PMID:18440500

  18. Synthesis of Hydrophobic, Crosslinkable Resins.

    DTIC Science & Technology

    1984-12-01

    insoluble products, in reactions analogous to the preparation of polyimides from polyamic acids . Examples fron7 the recent literature are provided by the...Vilsmeyer formylation,using a secondary amine with formic acid and phosphorous oxychloride [471. d. Probably the most convenient method utilises...such as styrene react with Lewis acids and so the scope for Friedel Crafts reactions is limited. Stilbene and its derivatives may be employed in such

  19. Rule Systems for Runtime Verification: A Short Tutorial

    NASA Astrophysics Data System (ADS)

    Barringer, Howard; Havelund, Klaus; Rydeheard, David; Groce, Alex

    In this tutorial, we introduce two rule-based systems for on and off-line trace analysis, RuleR and LogScope. RuleR is a conditional rule-based system, which has a simple and easily implemented algorithm for effective runtime verification, and into which one can compile a wide range of temporal logics and other specification formalisms used for runtime verification. Specifications can be parameterized with data, or even with specifications, allowing for temporal logic combinators to be defined. We outline a number of simple syntactic extensions of core RuleR that can lead to further conciseness of specification but still enabling easy and efficient implementation. RuleR is implemented in Java and we will demonstrate its ease of use in monitoring Java programs. LogScope is a derivation of RuleR adding a simple very user-friendly temporal logic. It was developed in Python, specifically for supporting testing of spacecraft flight software for NASA’s next 2011 Mars mission MSL (Mars Science Laboratory). The system has been applied by test engineers to analysis of log files generated by running the flight software. Detailed logging is already part of the system design approach, and hence there is no added instrumentation overhead caused by this approach. While post-mortem log analysis prevents the autonomous reaction to problems possible with traditional runtime verification, it provides a powerful tool for test automation. A new system is being developed that integrates features from both RuleR and LogScope.

  20. Bioinspired aerobic oxidation of secondary amines and nitrogen heterocycles with a bifunctional quinone catalyst.

    PubMed

    Wendlandt, Alison E; Stahl, Shannon S

    2014-01-08

    Copper amine oxidases are a family of enzymes with quinone cofactors that oxidize primary amines to aldehydes. The native mechanism proceeds via an iminoquinone intermediate that promotes high selectivity for reactions with primary amines, thereby constraining the scope of potential biomimetic synthetic applications. Here we report a novel bioinspired quinone catalyst system consisting of 1,10-phenanthroline-5,6-dione/ZnI2 that bypasses these constraints via an abiological pathway involving a hemiaminal intermediate. Efficient aerobic dehydrogenation of non-native secondary amine substrates, including pharmaceutically relevant nitrogen heterocycles, is demonstrated. The ZnI2 cocatalyst activates the quinone toward amine oxidation and provides a source of iodide, which plays an important redox-mediator role to promote aerobic catalytic turnover. These findings provide a valuable foundation for broader development of aerobic oxidation reactions employing quinone-based catalysts.

  1. Palladium-Catalyzed Anti-Markovnikov Oxidation of Allylic Amides to Protected β-Amino Aldehydes.

    PubMed

    Dong, Jia Jia; Harvey, Emma C; Fañanás-Mastral, Martín; Browne, Wesley R; Feringa, Ben L

    2014-12-10

    A general method for the preparation of N-protected β-amino aldehydes from allylic amines or linear allylic alcohols is described. Here the Pd(II)-catalyzed oxidation of N-protected allylic amines with benzoquinone is achieved in tBuOH under ambient conditions with excellent selectivity toward the anti-Markovnikov aldehyde products and full retention of configuration at the allylic carbon. The method shows a wide substrate scope and is tolerant of a range of protecting groups. Furthermore, β-amino aldehydes can be obtained directly from protected allylic alcohols via palladium-catalyzed autotandem reactions, and the application of this method to the synthesis of β-peptide aldehydes is described. From a mechanistic perspective, we demonstrate that tBuOH acts as a nucleophile in the reaction and that the initially formed tert-butyl ether undergoes spontaneous loss of isobutene to yield the aldehyde product. Furthermore, tBuOH can be used stoichiometrically, thereby broadening the solvent scope of the reaction. Primary and secondary alcohols do not undergo elimination, allowing the isolation of acetals, which subsequently can be hydrolyzed to their corresponding aldehyde products.

  2. Direct Displacement of Alkoxy Groups of Vinylogous Esters by Grignard Reagents

    PubMed Central

    Brockway, Anthony J.; González-López, Marcos; Fettinger, James C.

    2011-01-01

    The direct displacement of alkoxy groups from the beta position of aromatic and unsaturated esters and ketones is described. The reaction is chemo- and regioselective, displaying wide substrate scope. PMID:21446670

  3. Practical Iron- and Cobalt-Catalyzed Cross-Coupling Reactions between N-Heterocyclic Halides and Aryl or Heteroaryl Magnesium Reagents.

    PubMed

    Kuzmina, Olesya M; Steib, Andreas K; Fernandez, Sarah; Boudot, Willy; Markiewicz, John T; Knochel, Paul

    2015-05-26

    The reaction scope of iron- and cobalt-catalyzed cross-coupling reactions in the presence of isoquinoline (quinoline) in the solvent mixture tBuOMe/THF has been further investigated. Various 2-halogenated pyridine, pyrimidine, and triazine derivatives were arylated under these mild conditions in excellent yields. The presence of isoquinoline allows us to perform Fe-catalyzed cross-coupling reactions between 6-chloroquinoline and aryl magnesium reagents. Furthermore, it was found that the use of 10% N,N-dimethylquinoline-8-amine increases the yields of some Co-catalyzed cross-coupling reactions with chloropyridines bearing electron-withdrawing substituents. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Copper(II) Carboxylate Promoted Intramolecular Diamination of Terminal Alkenes: Improved Reaction Conditions and Expanded Substrate Scope

    PubMed Central

    Zabawa, Thomas P.

    2008-01-01

    The copper(II) carboxylate promoted diamination reaction has been improved by the use of the organic soluble copper(II) neodecanoate [Cu(ND)2]. Cu(ND)2 allowed the less polar solvent, dichloroethane (DCE) to be used, and as a consequence, decomposition of less reactive substrates could be avoided. High diastereoselectivity was observed in the synthesis of 2,5-disubstituted pyrrolidines. Ureas, bis(anilines) and α-amido pyrroles derived from 2-allylaniline could also participate in the diamination reaction. PMID:17447781

  5. Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

    PubMed Central

    Heimgartner, Heinz

    2017-01-01

    The scope of applications of dialkyl dicyanofumarates and maleates as highly functionalized electron-deficient dipolarophiles, dienophiles and Michael acceptors is summarized. The importance for the studies on reaction mechanisms of cycloadditions is demonstrated. Multistep reactions with 1,2-diamines and β-aminoalcohols leading to diverse five- and six-membered heterocycles are discussed. Applications of dialkyl dicyanofumarates as oxidizing agents in the syntheses of disulfides and diselenides are described. The reactions with metallocenes leading to charge-transfer complexes with magnetic properties are also presented. PMID:29114328

  6. CuO nanoparticles catalyzed C-N, C-O, and C-S cross-coupling reactions: scope and mechanism.

    PubMed

    Jammi, Suribabu; Sakthivel, Sekarpandi; Rout, Laxmidhar; Mukherjee, Tathagata; Mandal, Santu; Mitra, Raja; Saha, Prasenjit; Punniyamurthy, Tharmalingam

    2009-03-06

    CuO nanoparticles have been studied for C-N, C-O, and C-S bond formations via cross-coupling reactions of nitrogen, oxygen, and sulfur nucleophiles with aryl halides. Amides, amines, imidazoles, phenols, alcohols and thiols undergo reactions with aryl iodides in the presence of a base such as KOH, Cs(2)CO(3), and K(2)CO(3) at moderate temperature. The procedure is simple, general, ligand-free, and efficient to afford the cross-coupled products in high yield.

  7. Alkylsilyl Peroxides as Alkylating Agents in the Copper-Catalyzed Selective Mono-N-Alkylation of Primary Amides and Arylamines.

    PubMed

    Sakamoto, Ryu; Sakurai, Shunya; Maruoka, Keiji

    2017-07-06

    The copper-catalyzed selective mono-N-alkylation of primary amides or arylamines using alkylsilyl peroxides as alkylating agents is reported. The reaction proceeds under mild reaction conditions and exhibits a broad substrate scope with respect to the alkylsilyl peroxides, as well as to the primary amides and arylamines. Mechanistic studies suggest that the present reaction should proceed through a free-radical process that includes alkyl radicals generated from the alkylsilyl peroxides. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Copper-catalyzed oxidative homo- and cross-coupling of Grignard reagents using diaziridinone.

    PubMed

    Zhu, Yingguang; Xiong, Tao; Han, Wenyong; Shi, Yian

    2014-12-05

    Transition-metal-catalyzed cross-coupling reactions are among the most powerful synthetic transformations. This paper describes an efficient copper-catalyzed homo- and cross-coupling of Grignard reagents with di-tert-butyldiaziridinone as oxidant under mild conditions, giving the coupling products in good to excellent yields. The reaction process has a broad substrate scope and is also effective for the C(sp)-C(sp(3)) coupling.

  9. (3+3)-Annulation of Donor-Acceptor Cyclopropanes with Diaziridines.

    PubMed

    Trushkov, Igor V; Chagarovskiy, Alexey O; Vasin, Vladimir S; Kuznetsov, Vladimir V; Ivanova, Olga A; Rybakov, Victor B; Shumsky, Alexey N; Makhova, Nina N

    2018-06-23

    The first example of (3+3)-annulation of two different three-membered rings is reported herein. Donor-acceptor cyclopropanes in reaction with diaziridines were found to afford perhydropyridazine derivatives in high yields and diastereoselectivity under mild Lewis acid catalysis. The disclosed reaction is applicable for the broad substrate scope and exhibits an excellent functional group tolerance. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. On the Geometry of Chemical Reaction Networks: Lyapunov Function and Large Deviations

    NASA Astrophysics Data System (ADS)

    Agazzi, A.; Dembo, A.; Eckmann, J.-P.

    2018-04-01

    In an earlier paper, we proved the validity of large deviations theory for the particle approximation of quite general chemical reaction networks. In this paper, we extend its scope and present a more geometric insight into the mechanism of that proof, exploiting the notion of spherical image of the reaction polytope. This allows to view the asymptotic behavior of the vector field describing the mass-action dynamics of chemical reactions as the result of an interaction between the faces of this polytope in different dimensions. We also illustrate some local aspects of the problem in a discussion of Wentzell-Freidlin theory, together with some examples.

  11. Direct displacement of alkoxy groups of vinylogous esters by Grignard reagents.

    PubMed

    Brockway, Anthony J; González-López, Marcos; Fettinger, James C; Shaw, Jared T

    2011-05-06

    The direct displacement of alkoxy groups from the β position of aromatic and unsaturated esters and ketones is described. The reaction is chemo- and regioselective, displaying wide substrate scope. © 2011 American Chemical Society

  12. Final Technical Report for grant entitled "New Horizons in C-F Activation by Main Group Electrophiles"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ozerov, Oleg V; Ozerov, Oleg V.

    2014-01-16

    We became interested in developing new methods for hydrodefluorination (HDF) and other types of C-F bond conversion in polyfluoroalkanes under mild conditions. We were attracted to an approach to C-F activation, where the key C-F cleavage proceeds by a Lewis acid abstraction of fluoride rather than a redox event. The efforts during the previous period were aimed at a) advancing the HDF reactivity with improvement in scope and catalyst longevity; b) extending C-F activation beyond HDF; c) generating insight about the elementary steps of the reaction and potential intermediates.

  13. Isoelectronic Manganese and Iron Hydrogenation/Dehydrogenation Catalysts: Similarities and Divergences.

    PubMed

    Gorgas, Nikolaus; Kirchner, Karl

    2018-06-19

    Sustainable processes that utilize nontoxic, readily available, and inexpensive starting materials for organic synthesis constitute a major objective in modern chemical research. In this context, it is highly important to perform reactions under catalytic conditions and to replace precious metal catalysts by earth-abundant nonprecious metal catalysts. In particular, iron and manganese are promising candidates, as these are among the most abundant metals in the earth's crust, are inexpensive, and exhibit a low environmental impact. As far as chemical processes are concerned, hydrogenations and acceptorless alcohol dehydrogenation (AAD), sometimes in conjunction with hydrogen autotransfer reactions, are becoming important areas of research. While the first is a very important synthetic process representing a highly atom-efficient and clean methodology, AAD is an oxidant-free, environmentally benign reaction where carbonyl compounds together with dihydrogen as a valuable product and/or reactant (autotransfer) and water are formed. Carbonyl compounds, typically generated in situ, can be converted into other useful organic materials such as amines, imines, or heterocycles. In 2016 several groups, including ours, discovered for the first time the potential of hydride biscarbonyl Mn(I) complexes bearing strongly bound PNP pincer ligands or related tridentate ligands as highly effective and versatile catalysts for hydrogenation, transfer hydrogenation, and dehydrogenation reactions. These complexes are isoelectronic analogues of the respective hydride monocarbonyl Fe(II) PNP compounds and display similar reactivities but also quite divergent behavior depending on the coligands. Moreover, manganese compounds show improved long-term stability and high robustness toward harsh reaction conditions. In light of these recent achievements, this Account contrasts Mn(I) and Fe(II) PNP pincer catalysts, highlighting specific features that are connected to particular structural and electronic properties. It also addresses opportunities and restrictions in their catalytic applications. Apart from classical hydrogenations, it also covers the most recent developments of these catalysts for AAD resulting in the synthesis of complex organic molecules such as heterocycles via multicomponent reactions. The ambivalent hydrogen-based redox chemistry provides access to a variety of synthetically valuable reductive and oxidative coupling reactions. Hence, these catalysts cover a broad scope of catalytic applications and exhibit activities and productivities that are becoming competitive with those of well-established precious metal catalysts. The knowledge about the nature and characteristics of active Mn(I)- and Fe(II)-based systems paves the way for conceptually and mechanistically well-founded research, which might lead to further developments and the discovery of novel catalysts extending the current scope and limitations of reactivity. It underlines that base metal catalysts are beginning to challenge precious metal catalysts and contributes to the further advancement of waste-free sustainable base metal catalysis.

  14. Weak coordination as a powerful means for developing broadly useful C-H functionalization reactions.

    PubMed

    Engle, Keary M; Mei, Tian-Sheng; Wasa, Masayuki; Yu, Jin-Quan

    2012-06-19

    Reactions that convert carbon-hydrogen (C-H) bonds into carbon-carbon (C-C) or carbon-heteroatom (C-Y) bonds are attractive tools for organic chemists, potentially expediting the synthesis of target molecules through new disconnections in retrosynthetic analysis. Despite extensive inorganic and organometallic study of the insertion of homogeneous metal species into unactivated C-H bonds, practical applications of this technology in organic chemistry are still rare. Only in the past decade have metal-catalyzed C-H functionalization reactions become more widely utilized in organic synthesis. Research in the area of homogeneous transition metal-catalyzed C-H functionalization can be broadly grouped into two subfields. They reflect different approaches and goals and thus have different challenges and opportunities. One approach involves reactions of completely unfunctionalized aromatic and aliphatic hydrocarbons, which we refer to as "first functionalization". Here the substrates are nonpolar and hydrophobic and thus interact very weakly with polar metal species. To overcome this weak affinity and drive metal-mediated C-H cleavage, chemists often use hydrocarbon substrates in large excess (for example, as solvent). Because highly reactive metal species are needed in first functionalization, controlling the chemoselectivity to avoid overfunctionalization is often difficult. Additionally, because both substrates and products are comparatively low-value chemicals, developing cost-effective catalysts with exceptionally high turnover numbers that are competitive with alternatives (including heterogeneous catalysts) is challenging. Although an exciting field, first functionalization is beyond the scope of this Account. The second subfield of C-H functionalization involves substrates containing one or more pre-existing functional groups, termed "further functionalization". One advantage of this approach is that the existing functional group (or groups) can be used to chelate the metal catalyst and position it for selective C-H cleavage. Precoordination can overcome the paraffin nature of C-H bonds by increasing the effective concentration of the substrate so that it need not be used as solvent. From a synthetic perspective, it is desirable to use a functional group that is an intrinsic part of the substrate so that extra steps for installation and removal of an external directing group can be avoided. In this way, dramatic increases in molecular complexity can be accomplished in a single stroke through stereo- and site-selective introduction of a new functional group. Although reactivity is a major challenge (as with first functionalization), the philosophy in further functionalization differs; the major challenge is developing reactions that work with predictable selectivity in intricately functionalized contexts on commonly occurring structural motifs. In this Account, we focus on an emergent theme within the further functionalization literature: the use of commonly occurring functional groups to direct C-H cleavage through weak coordination. We discuss our motivation for studying Pd-catalyzed C-H functionalization assisted by weakly coordinating functional groups and chronicle our endeavors to bring reactions of this type to fruition. Through this approach, we have developed reactions with a diverse range of substrates and coupling partners, with the broad scope likely stemming from the high reactivity of the cyclopalladated intermediates, which are held together through weak interactions.

  15. Weak Coordination as a Powerful Means for Developing Broadly Useful C–H Functionalization Reactions

    PubMed Central

    Engle, Keary M.; Mei, Tian-Sheng; Wasa, Masayuki

    2011-01-01

    Conspectus Reactions that convert carbon–hydrogen (C–H) bonds into carbon–carbon (C–C) or carbon–heteroatom (C–Y) bonds are attractive tools for organic chemists, potentially expediting the synthesis of target molecules through new disconnections in retrosynthetic analysis. Despite extensive inorganic and organometallic study of the insertion of homogeneous metal species into unactivated C–H bonds, practical applications of this technology in organic chemistry are still rare. Only in the past decade have metal-catalyzed C–H functionalization reactions become more widely utilized in organic synthesis. Research in the area of homogeneous transition metal–catalyzed C–H functionalization can be broadly grouped into two subfields. They reflect different approaches and goals and thus have different challenges and opportunities. One approach involves reactions of completely unfunctionalized aromatic and aliphatic hydrocarbons, which we refer to as “first functionalization.” Here the substrates are nonpolar and hydrophobic and thus interact very weakly with polar metal species. To overcome this weak affinity and drive metal-mediated C–H cleavage, chemists often use hydrocarbon substrates in large excess (for example, as solvent). Because highly reactive metal species are needed in first functionalization, controlling the chemoselectivity to avoid over-functionalization is often difficult. Additionally, because both substrates and products are comparatively low-value chemicals, developing cost-effective catalysts with exceptionally high turnover numbers that are competitive with alternatives (including heterogeneous catalysts) is challenging. Although an exciting field, first functionalization is beyond the scope of this Account. The second subfield of C–H functionalization involves substrates containing one or more pre-existing functional groups, termed “further functionalization.” One advantage of this approach is that the existing functional group (or groups) can be used to chelate the metal catalyst and position it for selective C–H cleavage. Precoordination can overcome the paraffin nature of C–H bonds by increasing the effective concentration of the substrate so that it needn't be used as solvent. From a synthetic perspective, it is desirable to use a functional group that is an intrinsic part of the substrate so that extra steps for installation and removal of an external directing group can be avoided. In this way, dramatic increases in molecular complexity can be accomplished in a single stroke through stereo- and site-selective introduction of a new functional group. Although reactivity is a major challenge (as with first functionalization), the philosophy in further functionalization differs—the major challenge is developing reactions that work with predictable selectivity in intricately functionalized contexts on commonly occurring structural motifs. In this Account, we focus on an emergent theme within the further functionalization literature: the use of commonly occurring functional groups to direct C–H cleavage through weak coordinations. We discuss our motivation for studying Pd-catalyzed C–H functionalization assisted by weakly coordinating functional groups and chronicle our endeavors to bring reactions of this type to fruition. Through this approach, we have developed reactions with a diverse range of substrates and coupling partners, with the broad scope likely stemming from higher reactivity of the less stable cyclopalladated intermediates held in place by weak coordinations. PMID:22166158

  16. Engaging unactivated alkyl, alkenyl and aryl iodides in visible-light-mediated free radical reactions

    NASA Astrophysics Data System (ADS)

    Nguyen, John D.; D'Amato, Erica M.; Narayanam, Jagan M. R.; Stephenson, Corey R. J.

    2012-10-01

    Radical reactions are a powerful class of chemical transformations. However, the formation of radical species to initiate these reactions has often required the use of stoichiometric amounts of toxic reagents, such as tributyltin hydride. Recently, the use of visible-light-mediated photoredox catalysis to generate radical species has become popular, but the scope of these radical precursors has been limited. Here, we describe the identification of reaction conditions under which photocatalysts such as fac-Ir(ppy)3 can be utilized to form radicals from unactivated alkyl, alkenyl and aryl iodides. The generated radicals undergo reduction via hydrogen atom abstraction or reductive cyclization. The reaction protocol utilizes only inexpensive reagents, occurs under mild reaction conditions, and shows exceptional functional group tolerance. Reaction efficiency is maintained upon scale-up and decreased catalyst loading, and the reaction time can be significantly shortened when the reaction is performed in a flow reactor.

  17. Engineering an enantioselective amine oxidase for the synthesis of pharmaceutical building blocks and alkaloid natural products.

    PubMed

    Ghislieri, Diego; Green, Anthony P; Pontini, Marta; Willies, Simon C; Rowles, Ian; Frank, Annika; Grogan, Gideon; Turner, Nicholas J

    2013-07-24

    The development of cost-effective and sustainable catalytic methods for the production of enantiomerically pure chiral amines is a key challenge facing the pharmaceutical and fine chemical industries. This challenge is highlighted by the estimate that 40-45% of drug candidates contain a chiral amine, fueling a demand for broadly applicable synthetic methods that deliver target structures in high yield and enantiomeric excess. Herein we describe the development and application of a "toolbox" of monoamine oxidase variants from Aspergillus niger (MAO-N) which display remarkable substrate scope and tolerance for sterically demanding motifs, including a new variant, which exhibits high activity and enantioselectivity toward substrates containing the aminodiphenylmethane (benzhydrylamine) template. By combining rational structure-guided engineering with high-throughput screening, it has been possible to expand the substrate scope of MAO-N to accommodate amine substrates containing bulky aryl substituents. These engineered MAO-N biocatalysts have been applied in deracemization reactions for the efficient asymmetric synthesis of the generic active pharmaceutical ingredients Solifenacin and Levocetirizine as well as the natural products (R)-coniine, (R)-eleagnine, and (R)-leptaflorine. We also report a novel MAO-N mediated asymmetric oxidative Pictet-Spengler approach to the synthesis of (R)-harmicine.

  18. Intermolecular cope-type hydroamination of alkenes and alkynes using hydroxylamines.

    PubMed

    Moran, Joseph; Gorelsky, Serge I; Dimitrijevic, Elena; Lebrun, Marie-Eve; Bédard, Anne-Catherine; Séguin, Catherine; Beauchemin, André M

    2008-12-31

    The development of the Cope-type hydroamination as a method for the metal- and acid-free intermolecular hydroamination of hydroxylamines with alkenes and alkynes is described. Aqueous hydroxylamine reacts efficiently with alkynes in a Markovnikov fashion to give oximes and with strained alkenes to give N-alkylhydroxylamines, while unstrained alkenes are more challenging. N-Alkylhydroxylamines also display similar reactivity with strained alkenes and give modest to good yields with vinylarenes. Electron-rich vinylarenes lead to branched products while electron-deficient vinylarenes give linear products. A beneficial additive effect is observed with sodium cyanoborohydride, the extent of which is dependent on the structure of the hydroxylamine. The reaction conditions are found to be compatible with common protecting groups, free OH and NH bonds, as well as bromoarenes. Both experimental and theoretical results suggest the proton transfer step of the N-oxide intermediate is of vital importance in the intermolecular reactions of alkenes. Details are disclosed concerning optimization, reaction scope, limitations, and theoretical analysis by DFT, which includes a detailed molecular orbital description for the concerted hydroamination process and an exhaustive set of calculated potential energy surfaces for the reactions of various alkenes, alkynes, and hydroxylamines.

  19. Coordination-Assisted Bioorthogonal Chemistry: Orthogonal Tetrazine Ligation with Vinylboronic Acid and a Strained Alkene.

    PubMed

    Eising, Selma; Xin, Bo-Tao; Kleinpenning, Fleur; Heming, Juriaan; Florea, Bogdan; Overkleeft, Herman; Bonger, Kimberly Michelle

    2018-05-28

    Bioorthogonal chemistry can be used for the selective modification of biomolecules without interfering with any other functionality present. Recent developments in the field provided orthogonal bioorthogonal reactions for modification of multiple biomolecules simultaneously. During our research, we have observed exceptional high reaction rates in the bioorthogonal inverse electron-demand Diels-Alder (iEDDA) reaction between non-strained vinylboronic acids (VBAs) and dipyridyl-s-tetrazines relative to that of tetrazines bearing a methyl or phenyl substituent. As VBAs are mild Lewis acids, we hypothesize that coordination of the pyridyl nitrogen to the boronic acid promotes the tetrazine ligation. Here, we explore the molecular basis and scope of the VBA-tetrazine ligation in more detail and benefit from its unique reactivity in the simultaneous orthogonal tetrazine labelling of two proteins modified with VBA and norbornene, a widely used strained alkene. We further show that the two orthogonal iEDDA reactions can be carried out in living cells by labelling of the proteasome using a non-selective probe equipped with a VBA and a subunit-selective one bearing a norbornene. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Scoping reviews: time for clarity in definition, methods, and reporting.

    PubMed

    Colquhoun, Heather L; Levac, Danielle; O'Brien, Kelly K; Straus, Sharon; Tricco, Andrea C; Perrier, Laure; Kastner, Monika; Moher, David

    2014-12-01

    The scoping review has become increasingly popular as a form of knowledge synthesis. However, a lack of consensus on scoping review terminology, definition, methodology, and reporting limits the potential of this form of synthesis. In this article, we propose recommendations to further advance the field of scoping review methodology. We summarize current understanding of scoping review publication rates, terms, definitions, and methods. We propose three recommendations for clarity in term, definition and methodology. We recommend adopting the terms "scoping review" or "scoping study" and the use of a proposed definition. Until such time as further guidance is developed, we recommend the use of the methodological steps outlined in the Arksey and O'Malley framework and further enhanced by Levac et al. The development of reporting guidance for the conduct and reporting of scoping reviews is underway. Consistency in the proposed domains and methodologies of scoping reviews, along with the development of reporting guidance, will facilitate methodological advancement, reduce confusion, facilitate collaboration and improve knowledge translation of scoping review findings. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Effective Dropout Prevention Strategies Developed by the High/Scope Educational Research Foundation.

    ERIC Educational Resources Information Center

    Stellar, Arthur

    2002-01-01

    Introduces a collection of papers that address the High/Scope Foundation's approach to risk reduction and dropout prevention. Examines High/Scope's history and describes various High/Scope efforts (e.g., the Michigan School Readiness Program Evaluation, preschool and elementary curriculum development and training, movement and music curriculum…

  2. Solid-supported nitroso hetero Diels-Alder reactions. 1. Acylnitroso dienophiles: scope and limitations.

    PubMed

    Krchnák, Viktor; Moellmann, Ute; Dahse, Hans-Martin; Miller, Marvin J

    2008-01-01

    Polymer-supported acylnitroso dienophiles were prepared and used in hetero Diels-Alder (HDA) reactions with a variety of dienes. The transient acylnitroso dienophiles were prepared in situ from immobilized hydroxamates, which were attached to solid supports via several linkers each cleavable by different cleavage reagents, and served for the synthesis of both N-unsubstituted and N-derivatized HDA adducts. Model compounds were used to (i) optimize reaction conditions for solid-supported HDA reactions, (ii) evaluate the outcome of the reactions with various dienes, (iii) compare relative reactivities of dienes, and (iv) assess the stability of HDA adducts toward cleavage conditions typically used in solid-phase syntheses. Cleaved products were submitted to biological assays, and the results are reported. The accompanying paper, focused on complementary arylnitroso HDA reactions, includes a comparison of both HDA reactions.

  3. Copper-Catalyzed Oxidative Homo- and Cross-Coupling of Grignard Reagents Using Diaziridinone

    PubMed Central

    2015-01-01

    Transition-metal-catalyzed cross-coupling reactions are among the most powerful synthetic transformations. This paper describes an efficient copper-catalyzed homo- and cross-coupling of Grignard reagents with di-tert-butyldiaziridinone as oxidant under mild conditions, giving the coupling products in good to excellent yields. The reaction process has a broad substrate scope and is also effective for the C(sp)–C(sp3) coupling. PMID:25420218

  4. Organocatalytic Hydrophosphonylation Reaction of Carbonyl Groups.

    PubMed

    Herrera, Raquel P

    2017-09-01

    This revision is covering the limited examples reported for a pivotal strategy in the formation of C-P bonds such as the asymmetric organocatalytic hydrophosphonylation of carbonyl groups (Pudovik reaction). The scope and limitations, and the proposed mechanisms for the scarce different possibilities of asymmetric induction are also shown. The recent evolution and future trends of this undeveloped approach are commented. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Pauson-Khand reaction of internal dissymmetric trifluoromethyl alkynes. Influence of the alkene on the regioselectivity.

    PubMed

    Aiguabella, Nuria; Arce, Elsa M; Del Pozo, Carlos; Verdaguer, Xavier; Riera, Antoni

    2014-02-03

    The scope of the Pauson-Khand reaction (PKR) of internal trifluoromethyl alkynes, previously described with norbornadiene, is expanded to norbornene and ethylene. A thorough structural analysis of the resulting PK adducts has been carried out to unveil that α-trifluoromethylcyclopentenones are preferred in all cases, independently of the electronic properties of the alkyne. The regioselectivity observed with norbornadiene and ethylene is higher than in the case of norbornene.

  6. Scope and limitations of the Heck-Matsuda-coupling of phenol diazonium salts and styrenes: a protecting-group economic synthesis of phenolic stilbenes.

    PubMed

    Schmidt, Bernd; Elizarov, Nelli; Berger, René; Hölter, Frank

    2013-06-14

    4-Phenol diazonium salts undergo Pd-catalyzed Heck reactions with various styrenes to 4'-hydroxy stilbenes. In almost all cases higher yields and fewer side products were observed, compared to the analogous 4-methoxy benzene diazonium salts. In contrast, the reaction fails completely with 2- and 3-phenol diazonium salts. For these substitution patterns the methoxy-substituted derivatives are superior.

  7. Catalyst-free activation of methylene chloride and alkynes by amines in a three-component coupling reaction to synthesize propargylamines.

    PubMed

    Rawat, Vikas S; Bathini, Thulasiram; Govardan, S; Sreedhar, Bojja

    2014-09-14

    Propargylamines are synthesized via metal-free activation of the C-halogen bond of dihalomethanes and the C-H bond of terminal alkynes in a three-component coupling without catalyst or additional base and under mild reaction conditions. The dihalomethanes are used both as solvents as well as precursors for the methylene fragment (C1) in the final product. The scope of the reaction and the influence of various reaction variables has been investigated. A plausible reaction mechanism is proposed and the involvement of various intermediates that can be generated in situ in the process is discussed. The metal-free conditions also make this protocol environmentally benign and atom economical.

  8. Controlled release of volatiles under mild reaction conditions: from nature to everyday products.

    PubMed

    Herrmann, Andreas

    2007-01-01

    Volatile organic compounds serve in nature as semiochemicals for communication between species, and are often used as flavors and fragrances in our everyday life. The quite limited longevity of olfactive perception has led to the development of pro-perfumes or pro-fragrances--ideally nonvolatile and odorless fragrance precursors which release the active volatiles by bond cleavage. Only a limited amount of reaction conditions, such as hydrolysis, temperature changes, as well as the action of light, oxygen, enzymes, or microorganisms, can be used to liberate the many different chemical functionalities. This Review describes the controlled chemical release of fragrances and discusses additional challenges such as precursor stability during product storage as well as some aspects concerning toxicity and biodegradability. As the same systems can be applied in different areas of research, the scope of this Review covers fragrance delivery as well as the controlled release of volatiles in general.

  9. Bioinspired Aerobic Oxidation of Secondary Amines and Nitrogen Heterocycles with a Bifunctional Quinone Catalyst

    PubMed Central

    Wendlandt, Alison E.; Stahl, Shannon S.

    2014-01-01

    Copper amine oxidases are a family of enzymes with quinone cofactors that oxidize primary amines to aldehydes. The native mechanism proceeds via an iminoquinone intermediate that promotes high selectivity for reactions with primary amines, thereby constraining the scope of potential biomimetic synthetic applications. Here, we report a novel bioinspired quinone catalyst system, consisting of 1,10-phenanthroline-5,6-dione/ZnI2, that bypasses these constraints via an abiological pathway involving a hemiaminal intermediate. Efficient aerobic dehydrogenation of non-native secondary amine substrates, including pharmaceutically relevant nitrogen heterocycles, is demonstrated. The ZnI2 cocatalyst activates the quinone toward amine oxidation and provides a source of iodide, which plays an important redox-mediator role to promote aerobic catalytic turnover. These findings provide a valuable foundation for broader development of aerobic oxidation reactions employing quinone-based catalysts. PMID:24328193

  10. Self-powered gustation electronic skin for mimicking taste buds based on piezoelectric-enzymatic reaction coupling process

    NASA Astrophysics Data System (ADS)

    Zhao, Tianming; Fu, Yongming; He, Haoxuan; Dong, Chuanyi; Zhang, Linlin; Zeng, Hui; Xing, Lili; Xue, Xinyu

    2018-02-01

    A new self-powered wearable gustation electronic skin for mimicking taste buds has been realized based on enzyme-modified/ZnO nanowire arrays on patterned-electrode flexible substrate. The e-skin can actively taste beverages or fruits without any external electric power. Through the piezoelectric-enzymatic reaction coupling effect, the nanowires can harvest the mechanical energy of body movement and output piezoelectric signal. The piezoelectric output is significantly dependent on the concentration of target analyte. The response for detecting 2 × 10-2 M ascorbic acid (ascorbate acid oxidase@ZnO) is up to 171.747, and the selectivity is high. The response for detecting 50% alcohol (alcohol oxidase@ZnO) is up to 45.867. Our results provide a new research direction for the development of multifunctional e-skin and expand the study scope for self-powered bionic systems.

  11. Linking Metal Ions via Inorganic Click (iClick) Reactions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Veige, Adam

    2015-11-17

    This final report discusses the major objectives of the project, a discussion of the objectives achieved, a discussion of the objectives that failed, and finally, a discussion of future directions given the new knowledge obtained. This one-year seed project (with one year no-cost extension) contained three objectives: A) Expand the scope of iClick synthesis beyond AuI/AuI reactions. B) Elucidate a CuI-catalyzed iClick reaction. C) Synthesize and characterize tri- and tetra-metallic complexes as models for metallopolymers. Objectives A and C were achieved, whereas only parts of objective B were achieved.

  12. A new reactivity mode for the diazo group: diastereoselective 1,3-aminoalkylation reaction of β-amino-α-diazoesters to give triazolines.

    PubMed

    Kuznetsov, Alexey; Gulevich, Anton V; Wink, Donald J; Gevorgyan, Vladimir

    2014-08-18

    A novel mode of reactivity for the diazo group, the 1,3-addition of a nucleophile and an electrophile to the diazo group, has been realized in the intramolecular aminoalkylation of β-amino-α-diazoesters to form tetrasubstituted 1,2,3-triazolines. The reaction exhibited a broad scope, good functional group tolerance, and excellent diastereoselectivity. In addition, a new Au-catalyzed intramolecular transannulation reaction of the obtained propargyl triazolines to give pyrroles has been discovered. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Synthesis of (E)-2-Styrylchromones and Flavones by Base-Catalyzed Cyclodehydration of the Appropriate β-Diketones Using Water as Solvent.

    PubMed

    Pinto, Joana; Silva, Vera L M; Silva, Ana M G; Silva, Artur M S

    2015-06-22

    A low cost, safe, clean and environmentally benign base-catalyzed cyclodehydration of appropriate β-diketones affording (E)-2-styrylchromones and flavones in good yields is disclosed. Water was used as solvent and the reactions were heated using classical and microwave heating methods, under open and closed vessel conditions. β-Diketones having electron-donating and withdrawing substituents were used to evaluate the reaction scope. The reaction products were isolated in high purity by simple filtration and recrystallization from ethanol, when using 800 mg of the starting diketone under classical reflux heating conditions.

  14. Reactivity and Selectivity in Hydrovinylation of Strained Alkenes

    PubMed Central

    Liu, Wang; RajanBabu, T. V.

    2010-01-01

    Scope of Ni(II)-catalyzed hydrovinylation has been extended to strained alkenes such as heterobicyclic- [2.2.1]heptanes and cylobutenes. Reactions involving the heterobicyclic compounds are rare examples for this class of compounds where the metal-catalyzed C-C bond-forming reactions proceed without a concomitant ring-opening process. While the enantioselectivity in these systems remains modest, hydrovinylation of endo-5,6--bis-benzyloxymethylbicyclo[2.2.1]hept-2-ene gives excellent yield (>90%) of the product with one of the highest enantioselectivities (95–99 %ee) reported for a C-C bondforming reaction of norbornenes. PMID:20964350

  15. Alkyne Benzannulation Reactions for the Synthesis of Novel Aromatic Architectures.

    PubMed

    Hein, Samuel J; Lehnherr, Dan; Arslan, Hasan; J Uribe-Romo, Fernando; Dichtel, William R

    2017-11-21

    Aromatic compounds and polymers are integrated into organic field effect transistors, light-emitting diodes, photovoltaic devices, and redox-flow batteries. These compounds and materials feature increasingly complex designs, and substituents influence energy levels, bandgaps, solution conformation, and crystal packing, all of which impact performance. However, many polycyclic aromatic hydrocarbons of interest are difficult to prepare because their substitution patterns lie outside the scope of current synthetic methods, as strategies for functionalizing benzene are often unselective when applied to naphthalene or larger systems. For example, cross-coupling and nucleophilic aromatic substitution reactions rely on prefunctionalized arenes, and even directed metalation methods most often modify positions near Lewis basic sites. Similarly, electrophilic aromatic substitutions access single regioisomers under substrate control. Cycloadditions provide a convergent route to densely functionalized aromatic compounds that compliment the above methods. After surveying cycloaddition reactions that might be used to modify the conjugated backbone of poly(phenylene ethynylene)s, we discovered that the Asao-Yamamoto benzannulation reaction is notably efficient. Although this reaction had been reported a decade earlier, its scope and usefulness for synthesizing complex aromatic systems had been under-recognized. This benzannulation reaction combines substituted 2-(phenylethynyl)benzaldehydes and substituted alkynes to form 2,3-substituted naphthalenes. The reaction tolerates a variety of sterically congested alkynes, making it well-suited for accessing poly- and oligo(ortho-arylene)s and contorted hexabenzocoronenes. In many cases in which asymmetric benzaldehyde and alkyne cycloaddition partners are used, the reaction is regiospecific based on the electronic character of the alkyne substrate. Recognizing these desirable features, we broadened the substrate scope to include silyl- and halogen-substituted alkynes. Through a combined experimental and computational approach, we have elucidated mechanistic insight and key principles that govern the regioselectivity outcome of the benzannulation of structurally diverse alkynes. We have applied these methods to prepare sterically hindered, shape-persistent aromatic systems, heterocyclic aromatic compounds, functionalized 2-aryne precursors, polyheterohalogenated naphthalenes, ortho-arylene foldamers, and graphene nanoribbons. As a result of these new synthetic avenues, aromatic structures with interesting properties were uncovered such as ambipolar charge transport in field effect transistors based on our graphene nanoribbons, conformational aspects of ortho-arylene architectures resulting from intramolecular π-stacking, and modulation of frontier molecular orbitals via protonation of heteroatom containing aromatic systems. Given the availability of many substituted 2-(phenylethynyl)benzaldehydes and the regioselectivity of the benzannulation reaction, naphthalenes can be prepared with control of the substitution pattern at seven of the eight substitutable positions. Researchers in a range of fields are likely to benefit directly from newly accessible molecular and polymeric systems derived from polyfunctionalized naphthalenes.

  16. Metal‐Catalysed Azidation of Organic Molecules

    PubMed Central

    Goswami, Monalisa

    2016-01-01

    The azide moiety is a desirable functionality in organic molecules, useful in a variety of transformations such as olefin aziridination, C–H bond amination, isocyanate synthesis, the Staudinger reaction and the formation of azo compounds. To harness the versatility of the azide functionality fully it is important that these compounds be easy to prepare, in a clean and cost‐effective manner. Conventional (non‐catalysed) methods to synthesise azides generally require quite harsh reaction conditions that are often not tolerant of functional groups. In the last decade, several metal‐catalysed azidations have been developed in attempts to circumvent this problem. These methods are generally faster, cleaner and more functional‐group‐tolerant than conventional methods to prepare azides, and can sometimes even be conveniently combined with one‐pot follow‐up transformations of the installed azide moiety. This review highlights metal‐catalysed approaches to azide synthesis, with a focus on the substrate scopes and mechanisms, as well as on advantages and disadvantages of the methods. Overall, metal‐catalysed azidation reactions provide shorter routes to a variety of potentially useful organic molecules containing the azide moiety. PMID:28344503

  17. Synthesis of cis-C-Iodo-N-Tosyl-Aziridines using Diiodomethyllithium: Reaction Optimization, Product Scope and Stability, and a Protocol for Selection of Stationary Phase for Chromatography

    PubMed Central

    2013-01-01

    The preparation of C-iodo-N-Ts-aziridines with excellent cis-diastereoselectivity has been achieved in high yields by the addition of diiodomethyllithium to N-tosylimines and N-tosylimine–HSO2Tol adducts. This addition-cyclization protocol successfully provided a wide range of cis-iodoaziridines, including the first examples of alkyl-substituted iodoaziridines, with the reaction tolerating both aryl imines and alkyl imines. An ortho-chlorophenyl imine afforded a β-amino gem-diiodide under the optimized reaction conditions due to a postulated coordinated intermediate preventing cyclization. An effective protocol to assess the stability of the sensitive iodoaziridine functional group to chromatography was also developed. As a result of the judicious choice of stationary phase, the iodoaziridines could be purified by column chromatography; the use of deactivated basic alumina (activity IV) afforded high yield and purity. Rearrangements of electron-rich aryl-iodoaziridines have been promoted, selectively affording either novel α-iodo-N-Ts-imines or α-iodo-aldehydes in high yield. PMID:23738857

  18. A Transmetalation Reaction Enables the Synthesis of [18F]5-Fluorouracil from [18F]Fluoride for Human PET Imaging

    PubMed Central

    2016-01-01

    Translation of new 18F-fluorination reactions to produce radiotracers for human positron emission tomography (PET) imaging is rare because the chemistry must have useful scope and the process for 18F-labeled tracer production must be robust and simple to execute. The application of transition metal mediators has enabled impactful 18F-fluorination methods, but to date none of these reactions have been applied to produce a human-injectable PET tracer. In this article we present chemistry and process innovations that culminate in the first production from [18F]fluoride of human doses of [18F]5-fluorouracil, a PET tracer for cancer imaging in humans. The first preparation of nickel σ-aryl complexes by transmetalation from arylboronic acids or esters was developed and enabled the synthesis of the [18F]5-fluorouracil precursor. Routine production of >10 mCi doses of [18F]5-fluorouracil was accomplished with a new instrument for azeotrope-free [18F]fluoride concentration in a process that leverages the tolerance of water in nickel-mediated 18F-fluorination. PMID:27087736

  19. A Transmetalation Reaction Enables the Synthesis of [18F]5-Fluorouracil from [18F]Fluoride for Human PET Imaging.

    PubMed

    Hoover, Andrew J; Lazari, Mark; Ren, Hong; Narayanam, Maruthi Kumar; Murphy, Jennifer M; van Dam, R Michael; Hooker, Jacob M; Ritter, Tobias

    2016-04-11

    Translation of new 18 F-fluorination reactions to produce radiotracers for human positron emission tomography (PET) imaging is rare because the chemistry must have useful scope and the process for 18 F-labeled tracer production must be robust and simple to execute. The application of transition metal mediators has enabled impactful 18 F-fluorination methods, but to date none of these reactions have been applied to produce a human-injectable PET tracer. In this article we present chemistry and process innovations that culminate in the first production from [ 18 F]fluoride of human doses of [ 18 F]5-fluorouracil, a PET tracer for cancer imaging in humans. The first preparation of nickel σ-aryl complexes by transmetalation from arylboronic acids or esters was developed and enabled the synthesis of the [ 18 F]5-fluorouracil precursor. Routine production of >10 mCi doses of [ 18 F]5-fluorouracil was accomplished with a new instrument for azeotrope-free [ 18 F]fluoride concentration in a process that leverages the tolerance of water in nickel-mediated 18 F-fluorination.

  20. Preparative purification of polyethylene glycol derivatives with polystyrene-divinylbenzene beads as chromatographic packing.

    PubMed

    Yu, Pengzhan; Li, Xingqi; Li, Xiunan; Lu, Xiuling; Ma, Guanghui; Su, Zhiguo

    2007-10-15

    A clear and powerful chromatographic approach to purify polyethylene glycol derivatives at a preparative scale was reported, which was based on the polystyrene-divinylbenzene beads with ethanol/water as eluants. The validity of this method was verified with the reaction mixture of mPEG-Glu and mPEG propionaldehyde diethylacetal (ALD-PEG) as the model. The target products were one-step achieved with the purity of >99% on the polymer resins column at gram scale. The method developed was free from such disadvantages as utility of toxic solvent and narrow application scope, which was combined with conventional approaches. The method developed provided an appealing and attractive alternative methods for purification of PEG derivatives at a preparative scale.

  1. Catalyst-Directed Diastereoselective Isomerization of Allylic Alcohols for the Stereoselective Construction of C(20) in Steroid Side Chains: Scope and Topological Diversification.

    PubMed

    Li, Houhua; Mazet, Clément

    2015-08-26

    The stereoselective construction of C20 in steroidal derivatives by a highly diastereoselective Ir-catalyzed isomerization of primary allylic alcohols is reported. A key aspect of this strategy is a straightforward access to geometrically pure steroidal enol tosylate and enol triflate intermediates for subsequent high yielding stereoretentive Negishi cross-coupling reactions to allow structural diversity to be introduced. A range of allylic alcohols participates in the diastereoselective isomerization under the optimized reaction conditions. Electron-rich and electron-poor aryl or heteroaryl substituents are particularly well-tolerated, and the stereospecific nature of the reaction provides indifferently access to the natural C20-(R) and unnatural C20-(S) configurations. Alkyl containing substrates are more challenging as they affect regioselectivity of iridium-hydride insertion. A rationale for the high diastereoselectivities observed is proposed for aryl containing precursors. The scope of our method is further highlighted through topological diversification in the side chain and within the polycyclic domain of advanced and complex steroidal architectures. These findings have the potential to greatly simplify access to epimeric structural analogues of important steroid scaffolds for applications in biological, pharmaceutical, and medical sciences.

  2. The role of Facilities in Engaging and Informing the Public of EarthScope Science

    NASA Astrophysics Data System (ADS)

    Charlevoix, D. J.; Taber, J. J.; Berg, M.; Dorr, P. M.; McQuillan, P.; Olds, S. E.

    2013-12-01

    The IRIS and UNAVCO facilities play an important role in support of EarthScope through joint and independent education and outreach activities. These activities are focused on providing data and data products to a wide range of audiences, disseminating EarthScope science results through formal and informal venues, and informing the public of the broader impacts of EarthScope. The facilities are particularly well-suited for sustained engagement of multiple audiences over the decade-long course of EarthScope. One such example of a long-term effort was the Transportable Array student siting program, where over an 8 year period, students from about 55 institutions across the US and Canada conducted site reconnaissance and talked to landowners about EarthScope. Another activity focused on students was the development of a student intern program to support field engineering efforts during the construction of the Plate Boundary Observatory. Other ongoing activities include developing and maintaining relationships with media representatives and annual training of National Parks staff throughout the western U.S. The UNAVCO-IRIS partnership has been particularly valuable for EarthScope-related activities, where UNAVCO and IRIS work closely with the EarthScope National Office (ESNO) to bring EarthScope science to national, regional and local audiences within the EarthScope footprint. Collaborations have ranged across each group's products and services, including: EarthScope-focused teacher workshops, participation in EarthScope interpretive workshops for informal educators (led by ESNO), development of content for the IRIS Active Earth Monitor, preparing PBO-, USArray- and EarthScope-focused materials on topics such as Episodic Tremor and Slip for wider distribution through print, web, and mobile information technologies, and organizing research experiences for undergraduates on EarthScope-related topics. Other collaborations have focused on social media, and the development and dissemination of materials for the scientifically interested public at science and technology centers. The presentation will also share techniques used and future plans for evaluation of the public impact of EarthScope.

  3. The Evolution of Pd0/PdII-Catalyzed Aromatic Fluorination

    PubMed Central

    2016-01-01

    Conspectus Aromatic fluorides are prevalent in both agrochemical and pharmaceutical agents. However, methods for their rapid and general preparation from widely available starting materials are limited. Traditional approaches such as the Balz–Schiemann and Halex reactions require harsh conditions that limit functional group tolerance and substrate scope. The use of transition metals to affect C–F bond formation has provided some useful alternatives, but a broadly applicable method remains elusive. In contrast to the widespread use of Pd0/PdII catalysis for aryl–Z bond formation (Z = C, N, O), the analogous C–F cross-coupling process was unknown until fairly recently. In large part, this is due to the challenging Ar–F reductive elimination from Pd(II) intermediates. We have discovered that certain biaryl monophosphine ligands are uniquely capable of promoting this transformation. In this Account, we describe the discovery and development of a Pd-catalyzed C–F cross-coupling process and the systematic developments that made this once hypothetical reaction possible. Key to these developments was the discovery of an unusual in situ ligand modification process in which a molecule of substrate is incorporated into the ligand scaffold and the identity of the modifying group is crucial to the outcome of the reaction. This prompted the synthesis of a variety of “premodified” ligands and the identification of one that led to an expanded substrate scope, including (hetero)aryl triflates and bromides. Contemporaneously, a new Pd(0) precatalyst was also discovered that avoids the need to reduce Pd(II) in situ, a process that was often inefficient and led to the formation of byproducts. The use of inexpensive but hygroscopic sources of fluoride necessitates a reaction setup inside of a N2-filled glovebox, limiting the practicality of the method. Thus, a preformed wax capsule was designed to isolate the catalyst and reagents from the atmosphere and permit benchtop storage and setup. This new technology thus removes the requirement to employ a glovebox for the aromatic fluorination process and other air-sensitive protocols. In every catalyst system that we have studied to date, we observed the formation of regioisomeric fluoride side products. Through deuterium labeling studies it was found that they likely arise from a deprotonation event resulting in the formation of HF and a Pd–benzyne intermediate. Through an investigation of the mechanism of this undesired pathway, a new ligand was designed that substantially reduces the formation of the aryl fluoride regioisomer and even allows room-temperature Ar–F reductive elimination from a Pd(II) intermediate. PMID:27656765

  4. Red light running in Iowa : the scope, impact, and possible implications.

    DOT National Transportation Integrated Search

    2001-01-01

    Crashes related to red light running account for more than 800 deaths and thousands : of injuries each year in the United States. Many states and local jurisdictions : have undertaken studies and enacted programs in reaction to this major transportat...

  5. 25 CFR 224.73 - How will the scope of energy resource development affect the Secretary's determination of the...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false How will the scope of energy resource development affect... TRIBAL ENERGY DEVELOPMENT AND SELF DETERMINATION ACT Approval of Tribal Energy Resource Agreements § 224.73 How will the scope of energy resource development affect the Secretary's determination of the...

  6. 25 CFR 224.73 - How will the scope of energy resource development affect the Secretary's determination of the...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TRIBAL ENERGY DEVELOPMENT AND SELF DETERMINATION ACT Approval of Tribal Energy Resource Agreements § 224.73 How will the scope of energy resource development affect the Secretary's determination of the... 25 Indians 1 2010-04-01 2010-04-01 false How will the scope of energy resource development affect...

  7. Development of Catalysts and Ligands for Enantioselective Gold Catalysis

    PubMed Central

    Wang, Yi-Ming; Lackner, Aaron D.; Toste, F. Dean

    2014-01-01

    CONSPECTUS The use of Au(I) complexes for the catalytic activation of C-C π-bonds has been the subject of intense investigation in the last decade or so. The facile formation of carbon-carbon and carbon-heteroatom bonds facilitated by gold naturally led to efforts to render these transformations enantioselective. Early examples of enantioselective gold-catalyzed transformations have focused on bis(phosphinegold) complexes derived from axially chiral scaffolds. Although these complexes were highly successful in some reactions like cyclopropanation, careful choice of the weakly coordinating ligand (or counterion) was needed to obtain high levels of enantioselectivity for the case of allene hydroamination. These counterion effects led us to use the anion itself as a source of chirality, which was successful in the case of allene hydroalkoxylation. In order to expand the scope of reactions amenable to enantioselective gold catalysis to cycloadditions and other carbocyclization processes, a new class of mononuclear phosphite and phosphoramidite ligands was developed to supplement the previously widely utilized phosphines. Finally carbene ligands, in particular, the acyclic diaminocarbenes, have also been successfully applied to enantioselective transformations. PMID:24228794

  8. Sugar ester surfactants: enzymatic synthesis and applications in food industry.

    PubMed

    Neta, Nair S; Teixeira, José A; Rodrigues, Lígia R

    2015-01-01

    Sugar esters are non-ionic surfactants that can be synthesized in a single enzymatic reaction step using lipases. The stability and efficiency of lipases under unusual conditions and using non-conventional media can be significantly improved through immobilization and protein engineering. Also, the development of de novo enzymes has seen a significant increase lately under the scope of the new field of synthetic biology. Depending on the esterification degree and the nature of fatty acid and/or sugar, a range of sugar esters can be synthesized. Due to their surface activity and emulsifying capacity, sugar esters are promising for applications in food industry.

  9. Synthesis and Characterization of Manganese Sponge doped with TiO2

    NASA Astrophysics Data System (ADS)

    Mallikarjun, patil

    2017-06-01

    The aviation and mechanical industry has seen tremendous growth in recent years. While these trends only continue, the materials on development of better fabrication technologies. Spongy materials are projected as favourable materials for the future as porous in nature. The current paper devotes to enhance mechanical properties by the use of Manganese sponge doped with TiO2 possess an outstanding array of properties not readily achievable with other materials. Samples were synthesized by Kroll process and solid-state reaction. The specified materials compares well with the presently used aeromechanical materials in all terms. The scope for further research work in this area will be outlined.

  10. Palladium-catalyzed Suzuki-Miyaura coupling of amides by carbon-nitrogen cleavage: general strategy for amide N-C bond activation.

    PubMed

    Meng, Guangrong; Szostak, Michal

    2016-06-15

    The first palladium-catalyzed Suzuki-Miyaura cross-coupling of amides with boronic acids for the synthesis of ketones by sterically-controlled N-C bond activation is reported. The transformation is characterized by operational simplicity using bench-stable, commercial reagents and catalysts, and a broad substrate scope, including substrates with electron-donating and withdrawing groups on both coupling partners, steric-hindrance, heterocycles, halides, esters and ketones. The scope and limitations are presented in the synthesis of >60 functionalized ketones. Mechanistic studies provide insight into the catalytic cycle of the cross-coupling, including the first experimental evidence for Pd insertion into the amide N-C bond. The synthetic utility is showcased by a gram-scale cross-coupling and cross-coupling at room temperature. Most importantly, this process provides a blueprint for the development of a plethora of metal catalyzed reactions of typically inert amide bonds via acyl-metal intermediates. A unified strategy for amide bond activation to enable metal insertion into N-C amide bond is outlined ().

  11. Theoretical Modeling of Molecular and Electron Kinetic Processes. Volume I. Theoretical Formulation of Analysis and Description of Computer Program.

    DTIC Science & Technology

    1979-01-01

    syn- thesis proceed s by ignoring unacceptable syntax or other errors , pro- tection against subsequent execution of a faulty reaction scheme can be...resulting TAPE9 . During subroutine syn thesis and reaction processing, a search is made (fo r each secondary electron collision encountered) to...program library, which can be cat- alogued and saved if any future specialized modifications (beyond the scope of the syn thesis capability of LASER

  12. Construction of Pyrrolo[1,2-a]indoles via Cobalt(III)-Catalyzed Enaminylation of 1-(Pyrimidin-2-yl)-1H-indoles with Ketenimines and Subsequent Base-Promoted Cyclization.

    PubMed

    Zhou, Xiaorong; Fan, Zili; Zhang, Zhiyin; Lu, Ping; Wang, Yanguang

    2016-09-16

    A cobalt(III)-catalyzed cross-coupling reaction of 1-(pyrimidin-2-yl)-1H-indoles with ketenimines is reported. The reaction provided 2-enaminylated indole derivatives in moderate to excellent yields with a broad substrate scope. The prepared 2-enaminylated indoles could be conveniently converted into pyrrolo[1,2-a]indoles, which are an important class of compounds in medicinal chemistry.

  13. General Synthesis of Alkenyl Sulfides by Palladium-Catalyzed Thioetherification of Alkenyl Halides and Tosylates.

    PubMed

    Velasco, Noelia; Virumbrales, Cintia; Sanz, Roberto; Suárez-Pantiga, Samuel; Fernández-Rodríguez, Manuel A

    2018-05-08

    The cross-coupling reaction of alkenyl bromides with thiols catalyzed by palladium complexes derived from inexpensive dppf ligand is reported. These reactions occur under low catalyst loading and in high yields and display wide scope, including the coupling of bulky thiols and trisubstituted bromoolefins, and functional group tolerance. In addition, the thioetherification of less reactive chloroalkenes and, for the first time, alkenyl tosylates was accomplished using a catalyst generated from CyPF tBu alkylbisphosphine ligand.

  14. 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.

  15. Cross-Aldol Reaction of Activated Carbonyls with Nitrosocarbonyl Intermediates: Stereoselective Synthesis toward α-Hydroxy-β-amino Esters and Amides.

    PubMed

    Mallik, Sumitava; Bhajammanavar, Vinod; Ramakrishna, Isai; Baidya, Mahiuddin

    2017-07-21

    A practical and flexible strategy toward α-hydroxy-β-amino esters and amides, which are important biological motifs, based on an organocatalytic cross-aldol reaction of in situ-generated nitrosocarbonyl intermediates followed by hydrogenation is presented. The protocol features operational simplicity, high yields, a wide substrate scope, and high regio- and diastereoselectivity profiles. The utility of this method was showcased through the synthesis of bestatin analogues and indole formation.

  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) .

  17. 48 CFR 36.302 - Scope of work.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Scope of work. 36.302... Scope of work. The agency shall develop, either in-house or by contract, a scope of work that defines the project and states the Government's requirements. The scope of work may include criteria and...

  18. 48 CFR 36.302 - Scope of work.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Scope of work. 36.302... Scope of work. The agency shall develop, either in-house or by contract, a scope of work that defines the project and states the Government's requirements. The scope of work may include criteria and...

  19. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fetterly, Brandon Michael

    Nitric acid has been shown to be a weak acid in acetonitrile. It is conceivable that a nitrate salt of a weakly Lewis acidic cation could furnish a ''naked'' nitrate anion as a basic catalyst in a variety of reactions in non-aqueous solvents. Such a nitrate salt could also be bound to a polymeric support via the cation, thereby allowing for reclamation and recycling of the nitrate ion. This subject is dealt with in Chapter 2, wherein my contributions consisted of performing all the reactions with the polymer supported catalyst and carrying out the experiments necessary to shed light onmore » the reaction mechanisms. Chapter 3 contains a description of the structure and catalytic properties of an azidoproazaphosphatrane. This compound is an air-stable versatile catalyst that has proven useful not only homogeneously, but also when bound to a solid support. The synthesis of a polymer bound proazaphosphatrane containing a trivalent phosphorus is presented in Chapter 4. Such a compound has been sought after by our group for a number of years. Not only does the synthesis I have accomplished for it allow for easier separation of proazaphosphatrane catalysts from reaction mixtures, but recycling of the base is made much simpler. Proazaphosphatranes are useful homogeneous catalysts that activate atoms in other reagents, thus enhancing their reactivity. The next chapters deal with two such reactions with aldehydes and ketones, namely silylcyanations with trialkylsilylcyanides (Chapters 5 and 6) and reductions with poly(methylhydrosiloxane), in Chapter 7. In Chapter 5, Zhigang Wang performed the initial optimization and scoping of the reaction, while repetitions of the scoping experiments for reproducibility, determination of diastereomeric ratios, and experiments aimed at elucidating aspects of the mechanism were performed by me. The proazaphosphatrane coordinates to the silicon atom in both cases, thereby allowing the aforementioned reactions to proceed under much milder conditions. Proazaphosphatranes are also effective Broensted-Lowry bases. This is illustrated in Chapter 8 wherein a wide variety of conjugate addition reactions are catalyzed by proazaphosphatranes. In that chapter, repetitions of the nitroalkane addition reactions for reproducibility, improved spectral data for the products and comparisons of literature yields of all reactions were performed by the author.« less

  20. Enhancing the Scope of the Diels-Alder Reaction through Isonitrile Chemistry: Emergence of a New Class of Acyl-Activated Dienophiles

    PubMed Central

    Townsend, Steven D.; Wu, Xiangyang; Danishefsky, Samuel J.

    2012-01-01

    α,β-Unsaturated imides, formylated at the nitrogen atom, comprise a new and valuable family of dienophiles for servicing Diels-Alder reactions. These systems are assembled through extension of recently discovered isonitrile chemistry to the domain of α,β-unsaturated acids. Cycloadditions are facilitated by Et2AlCl, presumably via chelation between the two carbonyl groups of the N-formyl amide. Applications of the isonitrile/Diels-Alder logic to the IMDA reaction, as well as methodologies to modify the N-formyl amide of the resultant cycloaddition product, are described. It is expected that this easily executed chemistry will provide a significant enhancement for application of Diels-Alder reactions to many synthetic targets. PMID:22708980

  1. Enantioselective Intermolecular [2 + 2] Photocycloaddition Reactions of 2(1H)-Quinolones Induced by Visible Light Irradiation

    PubMed Central

    2016-01-01

    In the presence of a chiral thioxanthone catalyst (10 mol %) the title compounds underwent a clean intermolecular [2 + 2] photocycloaddition with electron-deficient olefins at λ = 419 nm. The reactions not only proceeded with excellent regio- and diastereoselectivity but also delivered the respective cyclobutane products with significant enantiomeric excess (up to 95% ee). Key to the success of the reactions is a two-point hydrogen bonding between quinolone and catalyst enabling efficient energy transfer and high enantioface differentiation. Preliminary work indicated that solar irradiation can be used for this process and that the substrate scope can be further expanded to isoquinolones. PMID:27268908

  2. α-Imino Esters in Organic Synthesis: Recent Advances.

    PubMed

    Eftekhari-Sis, Bagher; Zirak, Maryam

    2017-06-28

    α-Imino esters are useful precursors for the synthesis of a variety of types of natural and unnatural α-amino acid derivatives, with a wide range of biological activities. Due to the adjacent ester group, α-imino esters are more reactive relative to other types of imines and undergo different kinds of reactions, including organometallics addition, metal catalyzed vinylation and alkynylation, aza-Henry, aza-Morita-Baylis-Hillman, imino-ene, Mannich-type, and cycloaddition reactions, as well as hydrogenation and reduction. This review discusses the mechanism, scope, and applications of the reactions of α-imino esters and related compounds in organic synthesis, covering the literature from the last 12 years.

  3. Phosphine-catalyzed cycloadditions of allenic ketones: new substrates for nucleophilic catalysis.

    PubMed

    Wallace, Debra J; Sidda, Rachel L; Reamer, Robert A

    2007-02-02

    A range of phosphine-catalyzed cycloaddition reactions of allenic ketones have been studied, extending the scope of these processes from the more widely used 2,3-butadienoates to allow access to a number of synthetically useful products. Reaction of allenyl methyl ketone 4 with exo-enones afforded spirocyclic compounds in good regioselectivity and promising enantioselectivity via a [2 + 3] cycloaddtion. Aromatic allenyl ketones undergo a phosphine-promoted dimerization to afford functionalized pyrans, leading to a formal [2 + 4] Diels-Alder product, but did not react in the [2 + 3] cycloaddition. The results from other reactions that had found utility with 2,3-butadienoates are also reported.

  4. Fluorogenic Behaviour of the Hetero-Diels-Alder Ligation of 5-Alkoxyoxazoles with Maleimides and their Applications.

    PubMed

    Renault, Kévin; Jouanno, Laurie-Anne; Lizzul-Jurse, Antoine; Renard, Pierre-Yves; Sabot, Cyrille

    2016-12-19

    Fluorogenic reactions are largely underrepresented in the toolbox of chemoselective ligations despite their tremendous potential, particularly in chemical biology and biochemistry. In this respect, we have investigated in full detail the fluorescence behaviour of the azaphthalamide, a scaffold which is generated through a hetero-Diels-Alder reaction of 5-alkoxyoxazole and maleimide derivatives under mild conditions that are compatible with, among others, peptide chemistry. The scope and limitations of such a fluorogenic labelling strategy were examined through four distinct applications, which target enzymatic activities or bioorthogonal reactions. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Biocatalysis in organic chemistry and biotechnology: past, present, and future.

    PubMed

    Reetz, Manfred T

    2013-08-28

    Enzymes as catalysts in synthetic organic chemistry gained importance in the latter half of the 20th century, but nevertheless suffered from two major limitations. First, many enzymes were not accessible in large enough quantities for practical applications. The advent of recombinant DNA technology changed this dramatically in the late 1970s. Second, many enzymes showed a narrow substrate scope, often poor stereo- and/or regioselectivity and/or insufficient stability under operating conditions. With the development of directed evolution beginning in the 1990s and continuing to the present day, all of these problems can be addressed and generally solved. The present Perspective focuses on these and other developments which have popularized enzymes as part of the toolkit of synthetic organic chemists and biotechnologists. Included is a discussion of the scope and limitation of cascade reactions using enzyme mixtures in vitro and of metabolic engineering of pathways in cells as factories for the production of simple compounds such as biofuels and complex natural products. Future trends and problems are also highlighted, as is the discussion concerning biocatalysis versus nonbiological catalysis in synthetic organic chemistry. This Perspective does not constitute a comprehensive review, and therefore the author apologizes to those researchers whose work is not specifically treated here.

  6. Palladium/N-heterocyclic carbene catalysed regio and diastereoselective reaction of ketones with allyl reagents via inner-sphere mechanism

    PubMed Central

    Bai, Da-Chang; Yu, Fei-Le; Wang, Wan-Ying; Chen, Di; Li, Hao; Liu, Qing-Rong; Ding, Chang-Hua; Chen, Bo; Hou, Xue-Long

    2016-01-01

    The palladium-catalysed allylic substitution reaction is one of the most important reactions in transition-metal catalysis and has been well-studied in the past decades. Most of the reactions proceed through an outer-sphere mechanism, affording linear products when monosubstituted allyl reagents are used. Here, we report an efficient Palladium-catalysed protocol for reactions of β-substituted ketones with monosubstituted allyl substrates, simply by using N-heterocyclic carbene as ligand, leading to branched products with up to three contiguous stereocentres in a (syn, anti)-mode with excellent regio and diastereoselectivities. The scope of the protocol in organic synthesis has been examined preliminarily. Mechanistic studies by both experiments and density functional theory (DFT) calculations reveal that the reaction proceeds via an inner-sphere mechanism—nucleophilic attack of enolate oxygen on Palladium followed by C–C bond-forming [3,3']-reductive elimination. PMID:27283477

  7. Palladium/N-heterocyclic carbene catalysed regio and diastereoselective reaction of ketones with allyl reagents via inner-sphere mechanism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bai, Da -Chang; Yu, Fei -Le; Wang, Wan -Ying

    The palladium-catalysed allylic substitution reaction is one of the most important reactions in transition-metal catalysis and has been well-studied in the past decades. Most of the reactions proceed through an outer-sphere mechanism, affording linear products when monosubstituted allyl reagents are used. Here, we report an efficient Palladium-catalysed protocol for reactions of beta-substituted ketones with monosubstituted allyl substrates, simply by using N-heterocyclic carbene as ligand, leading to branched products with up to three contiguous stereocentres in a ( syn, anti)-mode with excellent regio and diastereoselectivities. The scope of the protocol in organic synthesis has been examined preliminarily. As a result, mechanisticmore » studies by both experiments and density functional theory ( DFT) calculations reveal that the reaction proceeds via an inner-sphere mechanism-nucleophilic attack of enolate oxygen on Palladium followed by C-C bond-forming [3,3']-reductive elimination.« less

  8. Palladium/N-heterocyclic carbene catalysed regio and diastereoselective reaction of ketones with allyl reagents via inner-sphere mechanism

    DOE PAGES

    Bai, Da -Chang; Yu, Fei -Le; Wang, Wan -Ying; ...

    2016-06-10

    The palladium-catalysed allylic substitution reaction is one of the most important reactions in transition-metal catalysis and has been well-studied in the past decades. Most of the reactions proceed through an outer-sphere mechanism, affording linear products when monosubstituted allyl reagents are used. Here, we report an efficient Palladium-catalysed protocol for reactions of beta-substituted ketones with monosubstituted allyl substrates, simply by using N-heterocyclic carbene as ligand, leading to branched products with up to three contiguous stereocentres in a ( syn, anti)-mode with excellent regio and diastereoselectivities. The scope of the protocol in organic synthesis has been examined preliminarily. As a result, mechanisticmore » studies by both experiments and density functional theory ( DFT) calculations reveal that the reaction proceeds via an inner-sphere mechanism-nucleophilic attack of enolate oxygen on Palladium followed by C-C bond-forming [3,3']-reductive elimination.« less

  9. Scope It Out: What's In and What's Out.

    PubMed

    Price, M Greta

    It has been nearly a year since the third edition of the Nursing Professional Development: Scope and Standards of Practice was released. During that time, many nursing professional development (NPD) departments across the nation have incorporated this foundational document into their practice. This column describes the activities of one NPD department to align their scope of practice with the NPD scope and standards and optimize their contributions to their organization.

  10. Applications of organocatalytic asymmetric synthesis to drug prototypes--dual action and selective inhibitors of n-nitric oxide synthase with activity against the 5-HT1D/1B subreceptors.

    PubMed

    Hanessian, Stephen; Stoffman, Eli; Mi, Xueling; Renton, Paul

    2011-03-04

    The scope of MacMillan's organocatalytic asymmetric conjugate addition reaction of indoles and electron-rich aromatics to α,β-unsaturated aldehydes has been extended to the use of 3-amino crotonaldehydes as substrates. The aromatics used include indoles as well as an aniline and a furan. The scope and effect of the groups on nitrogen (R, R') has also been studied. The method has been applied to the concise synthesis of an advanced precursor to S-(+)-1, a drug prototype for the treatment of migraine headaches.

  11. Rhodium(III)-Catalyzed Amidation of Unactivated C(sp(3) )-H Bonds.

    PubMed

    Wang, He; Tang, Guodong; Li, Xingwei

    2015-10-26

    Nitrogenation by direct functionalization of C-H bonds represents an important strategy for constructing C-N bonds. Rhodium(III)-catalyzed direct amidation of unactivated C(sp(3) )-H bonds is rare, especially under mild reaction conditions. Herein, a broad scope of C(sp(3) )-H bonds are amidated under rhodium catalysis in high efficiency using 3-substituted 1,4,2-dioxazol-5-ones as the amide source. The protocol broadens the scope of rhodium(III)-catalyzed C(sp(3) )-H activation chemistry, and is applicable to the late-stage functionalization of natural products. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Experimental and Theoretical Studies on the Nazarov Cyclization/Wagner-Meerwein Rearrangement Sequence

    PubMed Central

    Lebœuf, David; Ciesielski, Jennifer

    2012-01-01

    Highly functionalized cyclopentenones can be generated stereospecifically by a chemoselective copper(II)-mediated Nazarov/Wagner-Meerwein rearrangement sequence of divinyl ketones. A detailed investigation of this sequence is described including a study of substrate scope and limitations. After the initial 4π electrocyclization, this reaction proceeds via two different sequential [1,2]-shifts, with selectivity that depends upon either migratory ability or the steric bulkiness of the substituents at C1 and C5. This methodology allows the creation of vicinal stereogenic centers, including adjacent quaternary centers. This sequence can also be achieved by using a catalytic amount of copper(II) in combination with NaBAr4f, a weak Lewis acid. During the study of the scope of the reaction, a partial or complete E / Z isomerization of the enone moiety was observed in some cases prior to the cyclization, which resulted in a mixture of diastereomeric products. Use of a Cu(II)-bisoxazoline complex prevented the isomerization, allowing high diastereoselectivity to be obtained in all substrate types. In addition, the reaction sequence was studied by DFT computations at the UB3LYP/6-31G(d,p) level, which are consistent with the proposed sequences observed, including E / Z isomerizations and chemoselective Wagner-Meerwein shifts. PMID:22471833

  13. Iron-Catalyzed C-O Bond Activation: Opportunity for Sustainable Catalysis.

    PubMed

    Bisz, Elwira; Szostak, Michal

    2017-10-23

    Oxygen-based electrophiles have emerged as some of the most valuable cross-coupling partners in organic synthesis due to several major strategic and environmental benefits, such as abundance and potential to avoid toxic halide waste. In this context, iron-catalyzed C-O activation/cross-coupling holds particular promise to achieve sustainable catalytic protocols due to its natural abundance, inherent low toxicity, and excellent economic and ecological profile. Recently, tremendous progress has been achieved in the development of new methods for functional-group-tolerant iron-catalyzed cross-coupling reactions by selective C-O cleavage. These methods establish highly attractive alternatives to traditional cross-coupling reactions by using halides as electrophilic partners. In particular, new easily accessible oxygen-based electrophiles have emerged as substrates in iron-catalyzed cross-coupling reactions, which significantly broaden the scope of this catalysis platform. New mechanistic manifolds involving iron catalysis have been established; thus opening up vistas for the development of a wide range of unprecedented reactions. The synthetic potential of this sustainable mode of reactivity has been highlighted by the development of new strategies in the construction of complex motifs, including in target synthesis. The most recent advances in sustainable iron-catalyzed cross-coupling of C-O-based electrophiles are reviewed, with a focus on both mechanistic aspects and synthetic utility. It should be noted that this catalytic manifold provides access to motifs that are often not easily available by other methods, such as the assembly of stereodefined dienes or C(sp 2 )-C(sp 3 ) cross-couplings, thus emphasizing the synthetic importance of this mode of reactivity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. 36 CFR 903.1 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Purpose and scope. 903.1 Section 903.1 Parks, Forests, and Public Property PENNSYLVANIA AVENUE DEVELOPMENT CORPORATION PRIVACY ACT § 903.1 Purpose and scope. The purpose of this part is to enable the Pennsylvania Avenue Development...

  15. Alcohol and Kids: Facing Our Problem.

    ERIC Educational Resources Information Center

    Long, Nicholas; And Others

    1993-01-01

    Introduces special journal issue on alcohol use among children and adolescents. Describes scope of the problem, claiming that alcohol is the most consumed drug among children and youth. Discusses possible progression in alcohol use, parents' reactions to their children using alcohol or other drugs, and effects of the media and advertising on…

  16. What are scoping studies? A review of the nursing literature.

    PubMed

    Davis, Kathy; Drey, Nick; Gould, Dinah

    2009-10-01

    Scoping studies are increasingly undertaken as distinct activities. The interpretation, methodology and expectations of scoping are highly variable. This suggests that conceptually, scoping is a poorly defined ambiguous term. The distinction between scoping as an integral preliminary process in the development of a research proposal or a formative, methodologically rigorous activity in its own right has not been extensively examined. The aim of this review is to explore the nature and status of scoping studies within the nursing literature and develop a working definition to ensure consistency in the future use of scoping as a research related activity. This paper follows an interpretative scoping review methodology. An explicit systematic search strategy included literary and web-based key word searches and advice from key researchers. Electronic sources included bibliographic and national research register databases and a general browser. The scoping studies varied widely in terms of intent, procedural and methodological rigor. An atheoretical stance was common although explicit conceptual clarification and development of a topic was limited. Four different levels of inquiry ranging from preliminary descriptive surveys to more substantive conceptual approaches were conceptualised. These levels reflected differing dimensional distinctions in which some activities constitute research whereas in others the scoping activities appear to fall outside the remit of research. Reconnaissance emerges as a common synthesising construct to explain the purpose of scoping. Scoping studies in relation to nursing are embryonic and continue to evolve. Its main strengths lie in its ability to extract the essence of a diverse body of evidence giving it meaning and significance that is both developmental and intellectually creative. As with other approaches to research and evidence synthesis a more standardized approach is required.

  17. From genomics to chemical genomics: new developments in KEGG

    PubMed Central

    Kanehisa, Minoru; Goto, Susumu; Hattori, Masahiro; Aoki-Kinoshita, Kiyoko F.; Itoh, Masumi; Kawashima, Shuichi; Katayama, Toshiaki; Araki, Michihiro; Hirakawa, Mika

    2006-01-01

    The increasing amount of genomic and molecular information is the basis for understanding higher-order biological systems, such as the cell and the organism, and their interactions with the environment, as well as for medical, industrial and other practical applications. The KEGG resource () provides a reference knowledge base for linking genomes to biological systems, categorized as building blocks in the genomic space (KEGG GENES) and the chemical space (KEGG LIGAND), and wiring diagrams of interaction networks and reaction networks (KEGG PATHWAY). A fourth component, KEGG BRITE, has been formally added to the KEGG suite of databases. This reflects our attempt to computerize functional interpretations as part of the pathway reconstruction process based on the hierarchically structured knowledge about the genomic, chemical and network spaces. In accordance with the new chemical genomics initiatives, the scope of KEGG LIGAND has been significantly expanded to cover both endogenous and exogenous molecules. Specifically, RPAIR contains curated chemical structure transformation patterns extracted from known enzymatic reactions, which would enable analysis of genome-environment interactions, such as the prediction of new reactions and new enzyme genes that would degrade new environmental compounds. Additionally, drug information is now stored separately and linked to new KEGG DRUG structure maps. PMID:16381885

  18. A Transmetalation Reaction Enables the Synthesis of [ 18F]5-Fluorouracil from [ 18F]Fluoride for Human PET Imaging

    DOE PAGES

    Hoover, Andrew J.; Lazari, Mark; Ren, Hong; ...

    2016-02-14

    Translation of new 18F-fluorination reactions to produce radiotracers for human positron emission tomography (PET) imaging is rare because the chemistry must have useful scope and the process for 18F-labeled tracer production must be robust and simple to execute. The application of transition metal mediators has enabled impactful 18F-fluorination methods, but to date none of these reactions have been applied to produce a human-injectable PET tracer. In this article we present chemistry and process innovations that culminate in the first production from [ 18F]fluoride of human doses of [ 18F]5-fluorouracil, a PET tracer for cancer imaging in humans. Here, the firstmore » preparation of nickel σ-aryl complexes by transmetalation from arylboronic acids or esters was developed and enabled the synthesis of the [ 18F]5-fluorouracil precursor. Routine production of >10 mCi doses of [ 18F]5-fluorouracil was accomplished with a new instrument for azeotrope-free [ 18F]fluoride concentration in a process that leverages the tolerance of water in nickel-mediated 18F-fluorination.« less

  19. Heterogeneous fenton catalysts based on activated carbon and related materials.

    PubMed

    Navalon, Sergio; Dhakshinamoorthy, Amarajothi; Alvaro, Mercedes; Garcia, Hermenegildo

    2011-12-16

    The Fenton reaction is widely used for remediation of waste water and for the degradation of organic pollutants in water. Currently, there is considerable interest to convert the classical Fenton reaction, which consumes stoichiometric amounts of iron(II) salts, into a catalytic process that is promoted by a solid. This review describes the work that has used carbonaceous materials either directly as catalysts or, more frequently, as a large-area support for catalytically activated transition metals or metal-oxide nanoparticles. The interest in this type of catalyst derives from the wide use of carbon in conventional water treatments and the wide applicability of the Fenton reaction. After two general sections that illustrate the scope and background of Fenton chemistry, the review describes the activity of activated carbon in the absence or presence of metal-containing particles. The last sections of the review focus on different types of carbonaceous materials, such as carbon nanotubes and diamond nanoparticles. The review concludes with a section that anticipates future developments in this area, which are aimed at overcoming the current limitations of low activity and occurrence of metal leaching. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. A Transmetalation Reaction Enables the Synthesis of [ 18F]5-Fluorouracil from [ 18F]Fluoride for Human PET Imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoover, Andrew J.; Lazari, Mark; Ren, Hong

    Translation of new 18F-fluorination reactions to produce radiotracers for human positron emission tomography (PET) imaging is rare because the chemistry must have useful scope and the process for 18F-labeled tracer production must be robust and simple to execute. The application of transition metal mediators has enabled impactful 18F-fluorination methods, but to date none of these reactions have been applied to produce a human-injectable PET tracer. In this article we present chemistry and process innovations that culminate in the first production from [ 18F]fluoride of human doses of [ 18F]5-fluorouracil, a PET tracer for cancer imaging in humans. Here, the firstmore » preparation of nickel σ-aryl complexes by transmetalation from arylboronic acids or esters was developed and enabled the synthesis of the [ 18F]5-fluorouracil precursor. Routine production of >10 mCi doses of [ 18F]5-fluorouracil was accomplished with a new instrument for azeotrope-free [ 18F]fluoride concentration in a process that leverages the tolerance of water in nickel-mediated 18F-fluorination.« less

  1. Challenging nickel-catalysed amine arylations enabled by tailored ancillary ligand design

    PubMed Central

    Lavoie, Christopher M.; MacQueen, Preston M.; Rotta-Loria, Nicolas L.; Sawatzky, Ryan S.; Borzenko, Andrey; Chisholm, Alicia J.; Hargreaves, Breanna K. V.; McDonald, Robert; Ferguson, Michael J.; Stradiotto, Mark

    2016-01-01

    Palladium-catalysed C(sp2)–N cross-coupling (that is, Buchwald–Hartwig amination) is employed widely in synthetic chemistry, including in the pharmaceutical industry, for the synthesis of (hetero)aniline derivatives. However, the cost and relative scarcity of palladium provides motivation for the development of alternative, more Earth-abundant catalysts for such transformations. Here we disclose an operationally simple and air-stable ligand/nickel(II) pre-catalyst that accommodates the broadest combination of C(sp2)–N coupling partners reported to date for any single nickel catalyst, without the need for a precious-metal co-catalyst. Key to the unprecedented performance of this pre-catalyst is the application of the new, sterically demanding yet electron-poor bisphosphine PAd-DalPhos. Featured are the first reports of nickel-catalysed room temperature reactions involving challenging primary alkylamine and ammonia reaction partners employing an unprecedented scope of electrophiles, including transformations involving sought-after (hetero)aryl mesylates for which no capable catalyst system is known. PMID:27004442

  2. KEGGtranslator: visualizing and converting the KEGG PATHWAY database to various formats.

    PubMed

    Wrzodek, Clemens; Dräger, Andreas; Zell, Andreas

    2011-08-15

    The KEGG PATHWAY database provides a widely used service for metabolic and nonmetabolic pathways. It contains manually drawn pathway maps with information about the genes, reactions and relations contained therein. To store these pathways, KEGG uses KGML, a proprietary XML-format. Parsers and translators are needed to process the pathway maps for usage in other applications and algorithms. We have developed KEGGtranslator, an easy-to-use stand-alone application that can visualize and convert KGML formatted XML-files into multiple output formats. Unlike other translators, KEGGtranslator supports a plethora of output formats, is able to augment the information in translated documents (e.g. MIRIAM annotations) beyond the scope of the KGML document, and amends missing components to fragmentary reactions within the pathway to allow simulations on those. KEGGtranslator is freely available as a Java(™) Web Start application and for download at http://www.cogsys.cs.uni-tuebingen.de/software/KEGGtranslator/. KGML files can be downloaded from within the application. clemens.wrzodek@uni-tuebingen.de Supplementary data are available at Bioinformatics online.

  3. A status of progress for the Laser Isotope Separation (LIS) process

    NASA Technical Reports Server (NTRS)

    Delionback, L. M.

    1976-01-01

    An overview of the Laser Isotope Separation (LIS) methodology is given together with illustrations showing a simplified version of the LIS technique, an example of the two-photon photoionization category, and a diagram depicting how the energy levels of various isotope influence the LIS process. Applications were proposed for the LIS system which, in addition to enriching uranium, could in themselves develop into programs of tremendous scope and breadth. These include the treatment of radioactive wastes from light-water nuclear reactors, enriching the deuterium isotope to make heavy-water, and enriching the light isotopes of such elements as titanium for aerospace weight-reducing programs. Economic comparisons of the LIS methodology with the current method of gaseous diffusion indicate an overwhelming advantage; the laser process promises to be 1000 times more efficient. The technique could also be utilized in chemical reactions with the tuned laser serving as a universal catalyst to determine the speed and direction of a chemical reaction.

  4. Complementary Strategies for Directed C(sp3 )-H Functionalization: A Comparison of Transition-Metal-Catalyzed Activation, Hydrogen Atom Transfer, and Carbene/Nitrene Transfer.

    PubMed

    Chu, John C K; Rovis, Tomislav

    2018-01-02

    The functionalization of C(sp 3 )-H bonds streamlines chemical synthesis by allowing the use of simple molecules and providing novel synthetic disconnections. Intensive recent efforts in the development of new reactions based on C-H functionalization have led to its wider adoption across a range of research areas. This Review discusses the strengths and weaknesses of three main approaches: transition-metal-catalyzed C-H activation, 1,n-hydrogen atom transfer, and transition-metal-catalyzed carbene/nitrene transfer, for the directed functionalization of unactivated C(sp 3 )-H bonds. For each strategy, the scope, the reactivity of different C-H bonds, the position of the reacting C-H bonds relative to the directing group, and stereochemical outcomes are illustrated with examples in the literature. The aim of this Review is to provide guidance for the use of C-H functionalization reactions and inspire future research in this area. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Oxidase catalysis via aerobically generated hypervalent iodine intermediates

    NASA Astrophysics Data System (ADS)

    Maity, Asim; Hyun, Sung-Min; Powers, David C.

    2018-02-01

    The development of sustainable oxidation chemistry demands strategies to harness O2 as a terminal oxidant. Oxidase catalysis, in which O2 serves as a chemical oxidant without necessitating incorporation of oxygen into reaction products, would allow diverse substrate functionalization chemistry to be coupled to O2 reduction. Direct O2 utilization suffers from intrinsic challenges imposed by the triplet ground state of O2 and the disparate electron inventories of four-electron O2 reduction and two-electron substrate oxidation. Here, we generate hypervalent iodine reagents—a broadly useful class of selective two-electron oxidants—from O2. This is achieved by intercepting reactive intermediates of aldehyde autoxidation to aerobically generate hypervalent iodine reagents for a broad array of substrate oxidation reactions. The use of aryl iodides as mediators of aerobic oxidation underpins an oxidase catalysis platform that couples substrate oxidation directly to O2 reduction. We anticipate that aerobically generated hypervalent iodine reagents will expand the scope of aerobic oxidation chemistry in chemical synthesis.

  6. New Optical Methods for Liveness Detection on Fingers

    PubMed Central

    Dolezel, Michal; Vana, Jan; Brezinova, Eva; Yim, Jaegeol; Shim, Kyubark

    2013-01-01

    This paper is devoted to new optical methods, which are supposed to be used for liveness detection on fingers. First we describe the basics about fake finger use in fingerprint recognition process and the possibilities of liveness detection. Then we continue with introducing three new liveness detection methods, which we developed and tested in the scope of our research activities—the first one is based on measurement of the pulse, the second one on variations of optical characteristics caused by pressure change, and the last one is based on reaction of skin to illumination with different wavelengths. The last part deals with the influence of skin diseases on fingerprint recognition, especially on liveness detection. PMID:24151584

  7. One-Pot Synthesis of N-Substituted β-Amino Alcohols from Aldehydes and Isocyanides.

    PubMed

    Cioc, Răzvan C; van der Niet, Daan J H; Janssen, Elwin; Ruijter, Eelco; Orru, Romano V A

    2015-05-18

    A practical two-stage one-pot synthesis of N-substituted β-amino alcohols using aldehydes and isocyanides as starting materials has been developed. This method features mild reaction conditions, broad scope, and general tolerance of functional groups. Based on a less common central carbon-carbon bond disconnection, this protocol complements traditional approaches that involve amines and various carbon electrophiles (epoxides, α-halo ketones, β-halohydrins). Medicinally relevant products can be prepared in a concise and efficient way from simple building blocks, as demonstrated in the synthesis of the antiasthma drug salbutamol. Upgrading the synthesis to an enantioselective variant is also feasible. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Propulsion at the Marshall Space Flight Center - A brief history

    NASA Technical Reports Server (NTRS)

    Jones, L. W.; Fisher, M. F.; Mccool, A. A.; Mccarty, J. P.

    1991-01-01

    The history of propulsion development at the NASA Marshall Space Flight Center is summarized, beginning with the development of the propulsion system for the Redstone missile. This course of propulsion development continues through the Jupiter IRBM, the Saturn family of launch vehicles and the engines that powered them, the Centaur upper stage and RL-10 engine, the Reactor In-Flight Test stage and the NERVA nuclear engine. The Space Shuttle Main Engine and Solid Rocket Boosters are covered, as are spacecraft propulsion systems, including the reaction control systems for the High Energy Astronomy Observatory and the Space Station. The paper includes a description of several technology efforts such as those in high pressure turbomachinery, aerospike engines, and the AS203 cyrogenic fluid management flight experiment. These and other propulsion projects are documented, and the scope of activities in support of these efforts at Marshall delineated.

  9. Selective formation of 2-imidazolines and 2-substituted oxazoles by using a three-component reaction.

    PubMed

    Elders, Niels; Ruijter, Eelco; de Kanter, Frans J J; Groen, Marinus B; Orru, Romano V A

    2008-01-01

    Selective formation of 2H-2-imidazolines and 2-substituted oxazoles by using a multicomponent reaction of amines, either aldehydes or ketones, and alpha-acidic isocyano amides or esters is described. By selecting the appropriate solvent, Ag(I) or Cu(I) catalyst, or by employing a weak Brønsted acid, the product formation can be fully controlled and directed quantitatively to the desired heterocyclic scaffold. The described experimental procedures not only significantly increase the scope of compatible inputs for this complexity-generating three-component reaction, but also allow for considerable chemical diversity: At least four diversity points in two distinct scaffolds can be exploited in this way.

  10. The hard start phenomena in hypergolic engines. Volume 3: Physical and combustion characteristics of engine residuals

    NASA Technical Reports Server (NTRS)

    Miron, Y.; Perlee, H. E.

    1974-01-01

    An investigation was conducted to determine the cause of starting problems in the hypergolic rocket engines of the Apollo reaction control (RCS) engines. The scope of the investigation was as follows: (1) to establish that chemical reactions occurred during the preignition and post combustion periods, (2) to identify the chemical species of the products of preignition and post combustion reaction, and (3) to determine the explosive nature of the identified species. The methods used in identifying the chemical products are described species. The infrared spectra, X-ray spectra, and other signatures of the compounds are presented. The physical and explosion characteristics of various hypergolic agents are reported.

  11. 32 CFR 553.3 - Scope and applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 3 2014-07-01 2014-07-01 false Scope and applicability. 553.3 Section 553.3 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES ARMY NATIONAL CEMETERIES § 553.3 Scope and applicability. (a) Scope. The development...

  12. Protecting‐Group‐Free Amidation of Amino Acids using Lewis Acid Catalysts

    PubMed Central

    Sabatini, Marco T.; Karaluka, Valerija; Lanigan, Rachel M.; Boulton, Lee T.; Badland, Matthew

    2018-01-01

    Abstract Amidation of unprotected amino acids has been investigated using a variety of ‘classical“ coupling reagents, stoichiometric or catalytic group(IV) metal salts, and boron Lewis acids. The scope of the reaction was explored through the attempted synthesis of amides derived from twenty natural, and several unnatural, amino acids, as well as a wide selection of primary and secondary amines. The study also examines the synthesis of medicinally relevant compounds, and the scalability of this direct amidation approach. Finally, we provide insight into the chemoselectivity observed in these reactions. PMID:29505683

  13. Radical Cation Salt-initiated Aerobic C-H Phosphorylation of N-Benzylanilines: Synthesis of a-Aminophosphonates.

    PubMed

    Jia, Xiao Dong; Liu, Xiaofei; Yuan, Yu; Li, Pengfei; Hou, Wentao; He, Kaixuan

    2018-06-03

    A radical cation salt-initiated phosphorylation of N-benzylanilines was realized through the aerobic oxidation of sp3 C-H bond, providing a series of α-aminophosphonates in high yields. The investigation of the reaction scope revealed that this mild catalyst system is superior in good functional group tolerance and high reaction efficiency. The mechanistic study implied that the cleavage of the sp3 C-H bond was involved in the rate-determining step. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Cyclization Cascades Initiated by 1,6-Conjugate Addition

    PubMed Central

    Brooks, Joshua L.; Frontier, Alison J.

    2012-01-01

    Dienyl diketones containing tethered acetates selectively undergo two different 1,6-conjugate addition-initiated cyclization cascades. One is a 1,6-conjugate addition/cyclization sequence with incorporation of the nucleophile, and the other is catalyzed by DABCO and is thought to proceed via a cyclic acetoxonium intermediate. The reaction behavior of substrates lacking the tethered acetate was also studied. The scope of both types of cyclization cascades, the role of the amine additive, and the factors controlling reactivity and selectivity in the two different reaction pathways is discussed. PMID:23004564

  15. Integrating EarthScope Research and Education on a National Scale

    NASA Astrophysics Data System (ADS)

    Hall-Wallace, M. K.; Boyd, T.; Richard, G.; Ellins, K.; Meertens, C.; Semken, S.; Taber, J.; Benthien, M.; Wald, L.; Marvinney, R.

    2002-12-01

    EarthScope's education and outreach mission is to ensure the EarthScope experiment creates as its legacy a public more knowledgeable and understanding of the scientific and societal contributions made by the EarthScope experiment and Earth science. It will fulfill this commitment by developing and disseminating products that utilize the data, models, technology and discoveries of EarthScope and that support existing education and outreach programs. EarthScope EON will carry out educational activities ranging from research experiences for students in grades K-16 to professional development for technical professionals and educators in both formal (e.g. K-20 classrooms) and informal (e.g. museums and parks) venues. It will also provide a wide range of outreach activities from organizing town halls or other local meetings in advance of an instrument deployment, to developing radio, print and video materials that inform the public about the EarthScope experiment and discoveries. The EarthScope Education and Outreach Network (EON) will be facilitated and coordinated through a national center; however, the bulk of the effort will be distributed among local EON alliances of various sizes designed to respond quickly and to meet the specific needs in a region. This allows EarthScope EON to provide customized services that engage culturally, economically and geographically diverse audiences at the national and local scales. The network will be built through national and local partnerships with existing science education and outreach programs at colleges, universities, research facilities and professional societies within the EarthScope community as well as relevant programs at museums and parks, state geologic surveys and emergency management agencies, and K-12 schools. These partnerships will allow EON to use existing resources, networks and expertise to gear up quickly and efficiently. As EON develops, it will reciprocate by contributing new resources and expertise to the partnerships that help improve public understanding of Earth systems overall and promote effective application of EarthScope discoveries.

  16. Copper(II)-Catalyzed Conversion of Aryl/Heteroaryl Boronic Acids, Boronates, and Trifluoroborates into the Corresponding Azides: Substrate Scope and Limitations.

    PubMed

    Grimes, Kimberly D; Gupte, Amol; Aldrich, Courtney C

    2010-05-01

    We report the copper(II)-catalyzed conversion of organoboron compounds into the corresponding azide derivatives. A systematic series of phenylboronic acid derivatives is evaluated to examine the importance of steric and electronic effects of the substituents on reaction yield as well as functional group compatibility. Heterocyclic substrates are also shown to participate in this mild reaction while compounds incorporating B-C(sp(3)) bonds are unreactive under the reaction conditions. The copper(II)-catalyzed boronic acid-azide coupling reaction is further extended to both boronate esters and potassium organotrifluoroborate salts. The method described herein complements existing procedures for the preparation of aryl azides from the respective amino, triazene, and halide derivatives and we expect that it will greatly facilitate copper- and ruthenium-catalyzed azide-alkyne cycloaddition reactions for the preparation of diversely functionalized 1-aryl- or 1-heteroaryl-1,2,3-triazoles derivatives.

  17. Acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with alcohols.

    PubMed

    Tait, Katrina; Horvath, Alysia; Blanchard, Nicolas; Tam, William

    2017-01-01

    The acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicylic alkene using alcohol nucleophiles were investigated. Although this acid-catalyzed ring-opening reaction did not cleave the cyclopropane unit as planned, this represent the first examples of ring-openings of cyclopropanated 3-aza-2-oxabicyclo[2.2.1]alkenes that lead to the cleavage of the C-O bond instead of the N-O bond. Different acid catalysts were tested and it was found that pyridinium toluenesulfonate in methanol gave the best yields in the ring-opening reactions. The scope of the reaction was successfully expanded to include primary, secondary, and tertiary alcohol nucleophiles. Through X-ray crystallography, the stereochemistry of the product was determined which confirmed an S N 2-like mechanism to form the ring-opened product.

  18. Boehmite-An Efficient and Recyclable Acid-Base Bifunctional Catalyst for Aldol Condensation Reaction.

    PubMed

    Reshma, P C Rajan; Vikneshvaran, Sekar; Velmathi, Sivan

    2018-06-01

    In this work boehmite was used as an acid-base bifunctional catalyst for aldol condensation reactions of aromatic aldehydes and ketones. The catalyst was prepared by simple sol-gel method using Al(NO3)3·9H2O and NH4OH as precursors. The catalyst has been characterized by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), UV-visible spectroscopy (DRS), BET surface area analyses. Boehmite is successfully applied as catalyst for the condensation reaction between 4-nitrobenzaldehyde and acetone as a model substrate giving α, β-unsaturated ketones without any side product. The scope of the reaction is extended for various substituted aldehydes. A probable mechanism has been suggested to explain the cooperative behavior of the acidic and basic sites. The catalyst is environmentally friendly and easily recovered from the reaction mixture. Also the catalyst is reusable up to 3 catalytic cycles.

  19. 22 CFR 228.02 - Scope and application.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Scope and application. 228.02 Section 228.02 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES ON SOURCE, ORIGIN AND NATIONALITY FOR COMMODITIES AND SERVICES FINANCED BY USAID Definitions and Scope of This Part § 228.02 Scope and application...

  20. Development of monoclonal antibody-based sandwich ELISA for detection of dextran.

    PubMed

    Wang, Sheng-Yu; Li, Zhe; Wang, Xian-Jiang; Lv, Sha; Yang, Yun; Zeng, Lian-Qiang; Luo, Fang-Hong; Yan, Jiang-Hua; Liang, Da-Feng

    2014-10-01

    Dextran as anti-nutritional factor is usually a result of bacteria activity and has associated serial problems during the process stream in the sugar industry and in medical therapy. A sensitive method is expected to detect dextran quantitatively. Here we generated four monoclonal antibodies (MAbs) against dextran using dextran T40 conjugated with bovine serum albumin (BSA) as immunogen in our lab following hybridoma protocol. Through pairwise, an MAb named D24 was determined to be conjugated with horseradish peroxidase (HRP) and was used in the establishment of a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) method for determination of dextran, in which MAb D9 was chosen as a capture antibody. The detection limit and working scope of the developed sandwich ELISA method were 3.9 ng/mL and 7.8-500 ng/mL with a correlation coefficient of 0.9909. In addition, the cross-reaction assay demonstrated that the method possessed high specificity with no significant cross-reaction with dextran-related substances, and the recovery rate ranged from 96.35 to 102.00%, with coefficient of variation ranging from 1.58 to 6.94%. These results indicated that we developed a detection system of MAb-based sandwich ELISA to measure dextran and this system should be a potential tool to determine dextran levels.

  1. Economic thermoregulatory response explains mismatch between thermal physiology and behaviour in newts.

    PubMed

    Gvoždík, Lumír; Kristín, Peter

    2017-03-15

    Temperature is an important factor determining distribution and abundance of organisms. Predicting the impact of warming climate on ectotherm populations requires information about species' thermal requirements, i.e. their so-called 'thermal niche'. The characterization of thermal niche remains a complicated task. We compared the applicability of two indirect approaches, based on reaction norm (aerobic scope curve) and optimality (preferred body temperature) concepts, for indirect estimation of thermal niche while using newts, Ichthyosaura alpestris , as a study system. If the two approaches are linked, then digesting newts should keep their body temperatures close to values maximizing aerobic scope for digestion. After feeding, newts maintained their body temperatures within a narrower range than did hungry individuals. The range of preferred body temperatures was well below the temperature maximizing aerobic scope for digestion. Optimal temperatures for factorial aerobic scope fell within the preferred body temperature range of digesting individuals. We conclude that digesting newts prefer body temperatures that are optimal for the maximum aerobic performance but relative to the maintenance costs. What might be termed the 'economic' thermoregulatory response explains the mismatch between thermal physiology and behaviour in this system. © 2017. Published by The Company of Biologists Ltd.

  2. Mobile APP for Motivation to Learning: An Engineering Case

    ERIC Educational Resources Information Center

    Jou, Min; Lin, Yen-Ting; Tsai, Hsieh-Chih

    2016-01-01

    Synthesis of Materials is regarded as an important core subject in engineering education. However, many concepts and knowledge in the material synthesis can be rather abstract and difficult to understand by the student learners. Experiments are limited in scope due to lack of equipment, control of toxic materials, and risks of chemical reactions,…

  3. Teaching Reaction Engineering Using the Attainable Region

    ERIC Educational Resources Information Center

    Metzger, Matthew J.; Glasser, Benjamin J.; Glasser, David; Hausberger, Brendon; Hildebrandt, Diane

    2007-01-01

    Ask a graduating chemical engineering student the following question: What makes one reactor different from the next? The answers received will often be unsatisfactory and will vary widely in scope. Some may cite the difference between the basic design equations, others may point out a PFR is "longer," and still others may state that it…

  4. Environmental Improvement (Air, Water, and Soil).

    ERIC Educational Resources Information Center

    Marquis, Ralph W., Ed.

    As a community service and continuing adult education program, the Graduate School of the U. S. Department of Agriculture sponsors a series of public lectures. This book contains the texts and reactions to one of the lecture series entitled "Environmental Improvement." Given in May, 1966, the series presented "Man and His Environment - Scope,…

  5. Kinetic profiling of prolinate-catalyzed α-amination of aldehydes.

    PubMed

    Hein, Jason E; Armstrong, Alan; Blackmond, Donna G

    2011-08-19

    Deconvolution of the role of off-cycle species from the desired catalytic cycle leads to an optimized protocol for the prolinate-catalyzed amination of aldehydes. The scope of complex reaction networks will be greatly broadened by understanding ancillary rate processes that influence the productive catalytic pathway. © 2011 American Chemical Society

  6. The scope and limitations of intramolecular Nicholas and Pauson-Khand reactions for the synthesis of tricyclic oxygen- and nitrogen-containing heterocycles.

    PubMed

    Closser, Kristina D; Quintal, Miriam M; Shea, Kevin M

    2009-05-15

    We studied the scope and limitations of a tandem intramolecular Nicholas/Pauson-Khand strategy for the synthesis of tricyclic oxygen- and nitrogen-containing heterocycles. This methodology enables conversion of simple acyclic starting materials into a series of previously unknown heterocyclic architectures. For the preparation of cyclic ethers (Z = O), tricyclic [5,6,5]- through [5,9,5]-systems (m = 1, n = 1-4) are available with the [5,7,5]- and [5,8,5]-systems amenable to quick and efficient synthesis. Tricyclic [5,7,5]- and [5,8,5]-amine-containing (Z = NTs) heterocycles can be successfully prepared. Attempts to make larger ring systems (Z = O, m = 2; Z = O, n = 5; or Z = NTs, n = 4-5) or prepare lactones via Nicholas reactions with carboxylic acid nucleophiles (available via oxidation of alcohol nucleophiles, Z = O) result in decomposition or dimerization. The latter process enables formation of 14-, 16-, and 18-membered ring diolides when using carboxylic acid nucleophiles. We also investigated the use of chiral amine promoters in the Pauson-Khand step but found no asymmetric induction.

  7. Methodology and Natural Product Syntehsis: (A) Novel Glycosyl Donors; (B) N-Sulfinyl Metallodienamines and Their Application to the Total Synthesis of (-)-Albocycline

    NASA Astrophysics Data System (ADS)

    Chatare, Vijay K.

    My research involved in two different areas, development of novel glycosylation methodology and scope in oligosaccharide synthesis. A new scaffold for antibiotic development targeting the bacterial cell wall: Total synthesis of Albocycline and its analogs to see the mechanism of action in cell wall biosynthesis. Developed novel gem-dimethyl analogs of Fraser-Reid's NPGs from 3,3-dimethyl 4-pentenol and 2,2-dimethyl 4-pentenol. These donors are stable toward acidic and basic conditions, which makes them step-efficient when compared to other glycosylating agents. The scope and reactivity of 3,3-dimethyl 4-pentenyl glycosides of glucose, mannose, galactose, and N-acetylglucosamine have been studied extensively for oligosaccharide synthesis. The donors are readily prepared from commercial starting materials and both glycosylation and hydrolysis yields are in the synthetically useful in oligosaccharide synthesis. NSMD methodology introduced a key step in albocycline synthesis, where (-)-albocycline has great biological activity against "superbug" methicillin-resistant Staphylococcus aureus (MRSA). We hypothesize that albocycline inhibits the first committed step in bacterial cell wall biosynthesis. We have successfully completed two generation syntheses of albocycline. Vinylogous aldol on the left-handed fragment, aldehyde to get selectively up alcohol at the C-8 position using Davis-Ellman sulfinylimine chemistry and then oxidation with Davis oxaziridine to access requisite stereochemistry at C-4 alcohol followed by Horner-Wadsworth-Emmons to access seco-acid. Finally, a Keck macrolactonization reaction provided access to desired (-)-Albocycline.

  8. Ynamides in Ring Forming Transformations

    PubMed Central

    WANG, XIAO-NA; YEOM, HYUN-SUK; FANG, LI-CHAO; HE, SHUZHONG; MA, ZHI-XIONG; KEDROWSKI, BRANT L.; HSUNG, RICHARD P.

    2013-01-01

    Conspectus The ynamide functional group activates carbon-carbon triple bonds through an attached nitrogen atom that bears an electron-withdrawing group. As a result, the alkyne has both electrophilic and nucleophilic properties. Through the selection of the electron-withdrawing group attached to nitrogen chemists can modulate the electronic properties and reactivity of ynamides, making these groups versatile synthetic building blocks. The reactions of ynamides also lead directly to nitrogen-containing products, which provides access to important structural motifs found in natural products and molecules of medicinal interest. Therefore, researchers have invested increasing time and research in the chemistry of ynamides in recent years. This Account surveys and assesses new organic transformations involving ynamides developed in our laboratory and in others around the world. We showcase the synthetic power of ynamides for rapid assembly of complex molecular structures. Among the recent reports of ynamide transformations, ring-forming reactions provide a powerful tool for generating molecular complexity quickly. In addition to their synthetic utility, such reactions are mechanistically interesting. Therefore, we focus primarily on the cyclization chemistry of ynamides. This Account highlights ynamide reactions that are useful in the rapid synthesis of cyclic and polycyclic structural manifolds. We discuss the mechanisms active in the ring formations and describe representative examples that demonstrate the scope of these reactions and provide mechanistic insights. In this discussion we feature examples of ynamide reactions involving radical cyclizations, ring-closing metathesis, transition metal and non-transition metal mediated cyclizations, cycloaddition reactions, and rearrangements. The transformations presented rapidly introduce structural complexity and include nitrogen within, or in close proximity to, a newly formed ring (or rings). Thus, ynamides have emerged as powerful synthons for nitrogen-containing heterocycles and nitrogen-substituted rings, and we hope this Account will promote continued interest in the chemistry of ynamides. PMID:24164363

  9. Rural Idaho Family Physicians' Scope of Practice

    ERIC Educational Resources Information Center

    Baker, Ed; Schmitz, David; Epperly, Ted; Nukui, Ayaka; Miller, Carissa Moffat

    2010-01-01

    Context: Scope of practice is an important factor in both training and recruiting rural family physicians. Purpose: To assess rural Idaho family physicians' scope of practice and to examine variations in scope of practice across variables such as gender, age and employment status. Methods: A survey instrument was developed based on a literature…

  10. Fusion Power measurement at ITER

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bertalot, L.; Barnsley, R.; Krasilnikov, V.

    2015-07-01

    Nuclear fusion research aims to provide energy for the future in a sustainable way and the ITER project scope is to demonstrate the feasibility of nuclear fusion energy. ITER is a nuclear experimental reactor based on a large scale fusion plasma (tokamak type) device generating Deuterium - Tritium (DT) fusion reactions with emission of 14 MeV neutrons producing up to 700 MW fusion power. The measurement of fusion power, i.e. total neutron emissivity, will play an important role for achieving ITER goals, in particular the fusion gain factor Q related to the reactor performance. Particular attention is given also tomore » the development of the neutron calibration strategy whose main scope is to achieve the required accuracy of 10% for the measurement of fusion power. Neutron Flux Monitors located in diagnostic ports and inside the vacuum vessel will measure ITER total neutron emissivity, expected to range from 1014 n/s in Deuterium - Deuterium (DD) plasmas up to almost 10{sup 21} n/s in DT plasmas. The neutron detection systems as well all other ITER diagnostics have to withstand high nuclear radiation and electromagnetic fields as well ultrahigh vacuum and thermal loads. (authors)« less

  11. Oxidative trifluoromethylation and trifluoromethylthiolation reactions using (trifluoromethyl)trimethylsilane as a nucleophilic CF3 source.

    PubMed

    Chu, Lingling; Qing, Feng-Ling

    2014-05-20

    The trifluoromethyl group is widely prevalent in many pharmaceuticals and agrochemicals because its incorporation into drug candidates could enhance chemical and metabolic stability, improve lipophilicity and bioavailability, and increase the protein bind affinity. Consequently, extensive attention has been devoted toward the development of efficient and versatile methods for introducing the CF3 group into various organic molecules. Direct trifluoromethylation reaction has become one of the most efficient and important approaches for constructing carbon-CF3 bonds. Traditionally, the nucleophilic trifluoromethylation reaction involves an electrophile and the CF3 anion, while the electrophilic trifluoromethylation reaction involves a nucleophile and the CF3 cation. In 2010, we proposed the concept of oxidative trifluoromethylation: the reaction of nucleophilic substrates and nucleophilic trifluoromethylation reagents in the presence of oxidants. In this Account, we describe our recent studies of oxidative trifluoromethylation reactions of various nucleophiles with CF3SiMe3 in the presence of oxidants. We have focused most of our efforts on constructing carbon-CF3 bonds via direct trifluoromethylation of various C-H bonds. We have demonstrated copper-mediated or -catalyzed or metal-free oxidative C-H trifluoromethylation of terminal alkynes, tertiary amines, arenes and heteroarenes, and terminal alkenes. Besides various C-H bonds, aryl boronic acids proved to be viable nucleophilic coupling partners for copper-mediated or -catalyzed cross-coupling reactions with CF3SiMe3. To further expand the reaction scope, we also applied H-phosphonates to the oxidative trifluoromethylation system to construct P-CF3 bonds. Most recently, we developed silver-catalyzed hydrotrifluoromethylation of unactivated olefins. These studies explore boronic acids, C-H bonds, and P-H bonds as novel nucleophiles in transition-metal-mediated or -catalyzed cross-coupling reactions with CF3SiMe3, opening new viewpoints for future trifluoromethylation reactions. Furthermore, we also achieved the oxidative trifluoromethylthiolation reactions of aryl boronic acids and terminal alkynes to construct carbon-SCF3 bonds by using CF3SiMe3 and elemental sulfur as the nucleophilic trifluoromethylthiolating reagent. These oxidative trifluoromethylation and trifluoromethylthiolation reactions tolerate a wide range of functional groups, affording a diverse array of CF3- and CF3S-containing compounds with high efficiencies, and provide elegant and complementary alternatives to classical trifluoromethylation and trifluoromethylthiolation reactions. Because of the importance of the CF3 and SCF3 moieties in pharmaceuticals and agrochemicals, these reactions would have potential applications in the life science fields.

  12. 24 CFR 3280.601 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Scope. 3280.601 Section 3280.601 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT...

  13. 24 CFR 3280.1 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Scope. 3280.1 Section 3280.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT...

  14. 24 CFR 3280.701 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Scope. 3280.701 Section 3280.701 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT...

  15. The Development of Multidimensional Analysis Tools for Asymmetric Catalysis and Beyond.

    PubMed

    Sigman, Matthew S; Harper, Kaid C; Bess, Elizabeth N; Milo, Anat

    2016-06-21

    In most modern organic chemistry reports, including many of ours, reaction optimization schemes are typically presented to showcase how reaction conditions have been tailored to augment the reaction's yield and selectivity. In asymmetric catalysis, this often involves evaluation of catalyst, solvent, reagent, and, sometimes, substrate features. Such an article will then detail the process's scope, which mainly focuses on its successes and briefly outlines the "limitations". These limitations or poorer-performing substrates are occasionally the result of obvious, significant changes to structure (e.g., a Lewis basic group binds to a catalyst), but frequently, a satisfying explanation for inferior performance is not clear. This is one of several reasons such results are not often reported. These apparent outliers are also commonplace in the evaluation of catalyst structure, although most of this information is placed in the Supporting Information. These practices are unfortunate because results that appear at first glance to be peculiar or poor are considerably more interesting than ones that follow obvious or intuitive trends. In other words, all of the data from an optimization campaign contain relevant information about the reaction under study, and the "outliers" may be the most revealing. Realizing the power of outliers as an entry point to entirely new reaction development is not unusual. Nevertheless, the concept that no data should be wasted when considering the underlying phenomena controlling the observations of a given reaction is at the heart of the strategy we describe in this Account. The idea that one can concurrently optimize a reaction to expose the structural features that control its outcomes would represent a transformative addition to the arsenal of catalyst development and, ultimately, de novo design. Herein we outline the development of a recently initiated program in our lab that unites optimization with mechanistic interrogation by correlating reaction outputs (e.g., electrochemical potential or enantio-, site, or chemoselectivity) with structural descriptors of the molecules involved. The ever-evolving inspiration for this program is rooted in outliers of classical linear free energy relationships. These outliers encouraged us to ask questions about the parameters themselves, suggest potential interactions at the source of the observed effects, and, of particular applicability, identify more sophisticated physical organic descriptors. Throughout this program, we have integrated techniques from disparate fields, including synthetic methodology development, mechanistic investigations, statistics, computational chemistry, and data science. The implementation of many of these strategies is described, and the resulting tools are illustrated in a wide range of case studies, which include data sets with simultaneous and multifaceted changes to the reagent, substrate, and catalyst structures. This tactic constitutes a modern approach to physical organic chemistry wherein no data are wasted and mechanistic hypotheses regarding sophisticated processes can be developed and probed.

  16. Lanthanum tricyanide-catalyzed acyl silane-ketone benzoin additions and kinetic resolution of resultant alpha-silyloxyketones.

    PubMed

    Tarr, James C; Johnson, Jeffrey S

    2010-05-21

    We report the full account of our efforts on the lanthanum tricyanide-catalyzed acyl silane-ketone benzoin reaction. The reaction exhibits a wide scope in both acyl silane (aryl, alkyl) and ketone (aryl-alkyl, alkyl-alkyl, aryl-aryl, alkenyl-alkyl, alkynyl-alkyl) coupling partners. The diastereoselectivity of the reaction has been examined in both cyclic and acyclic systems. Cyclohexanones give products arising from equatorial attack by the acyl silane. The diastereoselectivity of acyl silane addition to acyclic alpha-hydroxy ketones can be controlled by varying the protecting group to obtain either Felkin-Ahn or chelation control. The resultant alpha-silyloxyketone products can be resolved with selectivity factors from 10 to 15 by subjecting racemic ketone benzoin products to CBS reduction.

  17. 24 CFR 884.101 - Applicability and scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Applicability and scope. 884.101 Section 884.101 Housing and Urban Development Regulations Relating to Housing and Urban Development... AND URBAN DEVELOPMENT (SECTION 8 HOUSING ASSISTANCE PROGRAMS, SECTION 202 DIRECT LOAN PROGRAM, SECTION...

  18. 3D-Printing inside the Glovebox: A Versatile Tool for Inert-Gas Chemistry Combined with Spectroscopy.

    PubMed

    Lederle, Felix; Kaldun, Christian; Namyslo, Jan C; Hübner, Eike G

    2016-04-01

    3D-Printing with the well-established 'Fused Deposition Modeling' technology was used to print totally gas-tight reaction vessels, combined with printed cuvettes, inside the inert-gas atmosphere of a glovebox. During pauses of the print, the reaction flasks out of acrylonitrile butadiene styrene were filled with various reactants. After the basic test reactions to proof the oxygen tightness and investigations of the influence of printing within an inert-gas atmosphere, scope and limitations of the method are presented by syntheses of new compounds with highly reactive reagents, such as trimethylaluminium, and reaction monitoring via UV/VIS, IR, and NMR spectroscopy. The applicable temperature range, the choice of solvents, the reaction times, and the analytical methods have been investigated in detail. A set of reaction flasks is presented, which allow routine inert-gas syntheses and combined spectroscopy without modifications of the glovebox, the 3D-printer, or the spectrometers. Overall, this demonstrates the potential of 3D-printed reaction cuvettes to become a complementary standard method in inert-gas chemistry.

  19. Catalytic effects of histidine enantiomers and glycine on the formation of dileucine and dimethionine in the salt-induced peptide formation reaction.

    PubMed

    Li, Feng; Fitz, Daniel; Fraser, Donald G; Rode, Bernd M

    2010-01-01

    The salt-induced peptide formation (SIPF) reaction takes place readily under mild reaction conditions and proceeds via a copper complex. Its ease of reaction and the universality for prebiotic scenarios add weights to the arguments in favour of the importance of peptide and proteins in the tug of war with the RNA world hypothesis. In addition, the SIPF reaction has a preference for L-form amino acids in dipeptide formation, casting light on the puzzle of biohomochirality, especially for the amino acids with aliphatic side chains. A detailed investigation on the behaviour of aliphatic leucine in the SIPF reaction is presented in this paper, including the catalytic effects of glycine, L- and D-histidine as well as the stereoselectivity under all the reaction conditions above. The results show a relatively low reactivity and stereoselectivity of leucine in the SIPF reaction, while both glycine and histidine enantiomers remarkably increase the yields of dileucine by factors up to 40. Moreover, a comparative study of the effectiveness of L- and D-histidine in catalysing the formation of dimethionine was also carried out and extends the scope of mutual catalysis by amino acid enantiomers in the SIPF reaction.

  20. Thermodynamically Leveraged Tandem Catalysis for Ester RC(O)O–R' Bond Hydrogenolysis. Scope and Mechanism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lohr, Tracy L.; Li, Zhi; Assary, Rajeev S.

    2015-05-18

    Rapid and selective formal hydrogenolysis of aliphatic ester RC(O)O–R' linkages is achieved by a tandem homogeneous metal triflate + supported palladium catalytic system. The triflate catalyzes the mildly exothermic, turnover-limiting O–R' cleavage process, whereas the exothermic hydrogenation of the intermediate alkene further drives the overall reaction to completion.

  1. Thermodynamically leveraged Tandem catalysis for ester RC(O)O-R' bond hydrogenolysis. scope and mechanism.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lohr, Tracy L.; Li, Zhi; Assary, Rajeev S.

    2015-06-01

    Rapid and selective formal hydrogenolysis of aliphatic ester RC(O)O-R' linkages is achieved by a tandem homogeneous metal triflate + supported palladium catalytic system. The triflate catalyzes the mildly exothermic, turnover-limiting O-R' cleavage process, whereas the exothermic hydrogenation of the intermediate alkene further drives the overall reaction to completion.

  2. The Struggle for Equality: School Integration Controversy in New York City.

    ERIC Educational Resources Information Center

    Swanson, Bert E.

    A study of the problems and decision making processes associated with the integration of New York City's public schools focuses on the reaction of the dominant white community to proposed integration policies. The research was funded by the U.S. Office of Education, Cooperative Research Program. The volume discusses the scope and method of this…

  3. Transition-Metal Catalysis of Nucleophilic Substitution Reactions: A Radical Alternative to SN1 and SN2 Processes.

    PubMed

    Fu, Gregory C

    2017-07-26

    Classical methods for achieving nucleophilic substitutions of alkyl electrophiles (S N 1 and S N 2) have limited scope and are not generally amenable to enantioselective variants that employ readily available racemic electrophiles. Radical-based pathways catalyzed by chiral transition-metal complexes provide an attractive approach to addressing these limitations.

  4. Transition-Metal Catalysis of Nucleophilic Substitution Reactions: A Radical Alternative to SN1 and SN2 Processes

    PubMed Central

    2017-01-01

    Classical methods for achieving nucleophilic substitutions of alkyl electrophiles (SN1 and SN2) have limited scope and are not generally amenable to enantioselective variants that employ readily available racemic electrophiles. Radical-based pathways catalyzed by chiral transition-metal complexes provide an attractive approach to addressing these limitations. PMID:28776010

  5. EMSL Science Theme Advisory Panel Workshop - Atmospheric Aerosol Chemistry, Climate Change, and Air Quality

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baer, Donald R.; Finlayson-Pitts, Barbara J.; Allen, Heather C.

    2013-07-01

    This report contains the workshop scope and recommendations from the workshop attendees in identifying scientific gaps in new particle formation, growth and properties of particles and reactions in and on particles as well as the laboratory-focused capabilities, field-deployable capabilities and modeling/theory tools along with linking of models to fundamental data.

  6. Chiral Brønsted Acid-Catalyzed Allylboration of Aldehydes

    PubMed Central

    Jain, Pankaj; Antilla, Jon C.

    2010-01-01

    The catalytic enantioselective allylation of aldehydes is a long-standing problem with considerable interest to the chemical community. We wish to disclose a new high yielding and highly enantioselective chiral Brønsted acid-catalyzed allylboration of aldehydes. The reaction is shown to be highly general, with broad substrate scope that covers aryl, heteroaryl, α,β-unsaturated, and aliphatic aldehydes. The reaction conditions were also shown to be effective for the catalytic enantioselective crotylation of aldehydes. We believe that the high reactivity of the allyl boronate is due to protonation of the boronate oxygen by the chiral phosphoric acid catalyst. PMID:20690662

  7. Organocatalyzed asymmetric alpha-oxidation, alpha-aminoxylation and alpha-amination of carbonyl compounds.

    PubMed

    Vilaivan, Tirayut; Bhanthumnavin, Worawan

    2010-02-11

    Organocatalytic asymmetric alpha-oxidation and amination reactions of carbonyl compounds are highly useful synthetic methodologies, especially in generating chiral building blocks that previously have not been easily accessible by traditional methods. The concept is relatively new and therefore the list of new catalysts, oxidizing and aminating reagents, as well as new substrates, are expanding at an amazing rate. The scope of this review includes new reactions and catalysts, mechanistic aspects and synthetic applications of alpha-oxidation, hydroxylation, aminoxylation, amination, hydrazination, hydroxyamination and related alpha-heteroatom functionalization of aldehydes, ketones and related active methylene compounds published during 2005-2009.

  8. From ketones to esters by a Cu-catalyzed highly selective C(CO)-C(alkyl) bond cleavage: aerobic oxidation and oxygenation with air.

    PubMed

    Huang, Xiaoqiang; Li, Xinyao; Zou, Miancheng; Song, Song; Tang, Conghui; Yuan, Yizhi; Jiao, Ning

    2014-10-22

    The Cu-catalyzed aerobic oxidative esterification of simple ketones via C-C bond cleavage has been developed. Varieties of common ketones, even inactive aryl long-chain alkyl ketones, are selectively converted into esters. The reaction tolerates a wide range of alcohols, including primary and secondary alcohols, chiral alcohols with retention of the configuration, electron-deficient phenols, as well as various natural alcohols. The usage of inexpensive copper catalyst, broad substrate scope, and neutral and open air conditions make this protocol very practical. (18)O labeling experiments reveal that oxygenation occurs during this transformation. Preliminary mechanism studies indicate that two novel pathways are mainly involved in this process.

  9. 13 CFR 303.1 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 303.1 Business Credit and Assistance ECONOMIC DEVELOPMENT ADMINISTRATION, DEPARTMENT OF COMMERCE PLANNING INVESTMENTS AND COMPREHENSIVE ECONOMIC DEVELOPMENT STRATEGIES § 303.1 Purpose and scope. The purpose of EDA Planning Investments is to provide support to Planning Organizations for the development...

  10. Visit from JAXA to NASA MSFC: The Engines Element & Ideas for Collaboration

    NASA Technical Reports Server (NTRS)

    Greene, William D.

    2013-01-01

    System Design, Development, and Fabrication: Design, develop, and fabricate or procure MB-60 component hardware compliant with the imposed technical requirements and in sufficient quantities to fulfill the overall MB-60 development effort. System Development, Assembly, and Test: Manage the scope of the development, assembly, and test-related activities for MB-60 development. This scope includes engine-level development planning, engine assembly and disassembly, test planning, engine testing, inspection, anomaly resolution, and development of necessary ground support equipment and special test equipment. System Integration: Provide coordinated integration in the realms of engineering, safety, quality, and manufacturing disciplines across the scope of the MB-60 design and associated products development Safety and Mission Assurance, structural design, fracture control, materials and processes, thermal analysis. Systems Engineering and Analysis: Manage and perform Systems Engineering and Analysis to provide rigor and structure to the overall design and development effort for the MB-60. Milestone reviews, requirements management, system analysis, program management support Program Management: Manage, plan, and coordinate the activities across all portions of the MB-60 work scope by providing direction for program administration, business management, and supplier management.

  11. Focusing the EarthScope for a broader audience: Advancing geoscience education with interactive kiosks

    NASA Astrophysics Data System (ADS)

    Smith-Konter, B. R.; Solis, T.

    2012-12-01

    A primary objective of the EarthScope Education and Outreach program is to transform technical science into teachable products for a technologically thriving generation. One of the most challenging milestones of scientific research, however, is often the translation of a technical result into a clear teachable moment that is accessible to a broader audience. As 4D multimedia now dominate most aspects of our social environment, science "teaching" now also requires intervention of visualization technology and animation to portray research results in an inviting and stimulating manner. Following the Incorporated Research Institutions for Seismology (IRIS)'s lead in developing interactive Earth science kiosk multimedia (bundled in a free product called Active Earth), we have made a major effort to construct and install customized EarthScope-themed touch screen kiosks in local communities. These kiosks are helping to educate a broader audience about EarthScope's unique instrumentation and observations using interactive animations, games, and virtual field trips. We are also developing new kiosk content that reflect career stories showcasing the personal journeys of EarthScope scientists. To truly bring the interactive aspect of our EarthScope kiosk media into the classroom, we have collaborated with local teachers to develop a one-page EarthScope TerraMap activity worksheet that guides students through kiosk content. These activities are shaping a new pathway for how teachers teach and students learn about planet Earth and its fantastic EarthScope - one click (and touch) at a time.

  12. Bonded exciplex formation: electronic and stereoelectronic effects.

    PubMed

    Wang, Yingsheng; Haze, Olesya; Dinnocenzo, Joseph P; Farid, Samir; Farid, Ramy S; Gould, Ian R

    2008-12-18

    As recently proposed, the singlet-excited states of several cyanoaromatics react with pyridine via bonded-exciplex formation, a novel concept in photochemical charge transfer reactions. Presented here are electronic and steric effects on the quenching rate constants, which provide valuable support for the model. Additionally, excited-state quenching in poly(vinylpyridine) is strongly inhibited both relative to that in neat pyridine and also to conventional exciplex formation in polymers, consistent with a restrictive orientational requirement for the formation of bonded exciplexes. Examples of competing reactions to form both conventional and bonded exciplexes are presented, which illustrate the delicate balance between these two processes when their reaction energetics are similar. Experimental and computational evidence is provided for the formation of a bonded exciplex in the reaction of the singlet excited state of 2,6,9,10-tetracyanoanthracene (TCA) with an oxygen-substituted donor, dioxane, thus expanding the scope of bonded exciplexes.

  13. Exploiting and engineering hemoproteins for abiological carbene and nitrene transfer reactions.

    PubMed

    Brandenberg, Oliver F; Fasan, Rudi; Arnold, Frances H

    2017-10-01

    The surge in reports of heme-dependent proteins as catalysts for abiotic, synthetically valuable carbene and nitrene transfer reactions dramatically illustrates the evolvability of the protein world and our nascent ability to exploit that for new enzyme chemistry. We highlight the latest additions to the hemoprotein-catalyzed reaction repertoire (including carbene Si-H and C-H insertions, Doyle-Kirmse reactions, aldehyde olefinations, azide-to-aldehyde conversions, and intermolecular nitrene C-H insertion) and show how different hemoprotein scaffolds offer varied reactivity and selectivity. Preparative-scale syntheses of pharmaceutically relevant compounds accomplished with these new catalysts are beginning to demonstrate their biotechnological relevance. Insights into the determinants of enzyme lifetime and product yield are providing generalizable cues for engineering heme-dependent proteins to further broaden the scope and utility of these non-natural activities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Enantiospecific sp2-sp3 coupling of secondary and tertiary boronic esters

    NASA Astrophysics Data System (ADS)

    Bonet, Amadeu; Odachowski, Marcin; Leonori, Daniele; Essafi, Stephanie; Aggarwal, Varinder K.

    2014-07-01

    The cross-coupling of boronic acids and related derivatives with sp2 electrophiles (the Suzuki-Miyaura reaction) is one of the most powerful C-C bond formation reactions in synthesis, with applications that span pharmaceuticals, agrochemicals and high-tech materials. Despite the breadth of its utility, the scope of this Nobel prize-winning reaction is rather limited when applied to aliphatic boronic esters. Primary organoboron reagents work well, but secondary and tertiary boronic esters do not (apart from a few specific and isolated examples). Through an alternative strategy, which does not involve using transition metals, we have discovered that enantioenriched secondary and tertiary boronic esters can be coupled to electron-rich aromatics with essentially complete enantiospecificity. As the enantioenriched boronic esters are easily accessible, this reaction should find considerable application, particularly in the pharmaceutical industry where there is growing awareness of the importance of, and greater clinical success in, creating biomolecules with three-dimensional architectures.

  15. Quantitating T cell cross-reactivity for unrelated peptide antigens.

    PubMed

    Ishizuka, Jeffrey; Grebe, Kristie; Shenderov, Eugene; Peters, Bjoern; Chen, Qiongyu; Peng, Yanchun; Wang, Lili; Dong, Tao; Pasquetto, Valerie; Oseroff, Carla; Sidney, John; Hickman, Heather; Cerundolo, Vincenzo; Sette, Alessandro; Bennink, Jack R; McMichael, Andrew; Yewdell, Jonathan W

    2009-10-01

    Quantitating the frequency of T cell cross-reactivity to unrelated peptides is essential to understanding T cell responses in infectious and autoimmune diseases. Here we used 15 mouse or human CD8+ T cell clones (11 antiviral, 4 anti-self) in conjunction with a large library of defined synthetic peptides to examine nearly 30,000 TCR-peptide MHC class I interactions for cross-reactions. We identified a single cross-reaction consisting of an anti-self TCR recognizing a poxvirus peptide at relatively low sensitivity. We failed to identify any cross-reactions between the synthetic peptides in the panel and polyclonal CD8+ T cells raised to viral or alloantigens. These findings provide the best estimate to date of the frequency of T cell cross-reactivity to unrelated peptides ( approximately 1/30,000), explaining why cross-reactions between unrelated pathogens are infrequently encountered and providing a critical parameter for understanding the scope of self-tolerance.

  16. Quantitating T Cell Cross-Reactivity for Unrelated Peptide Antigens1

    PubMed Central

    Ishizuka, Jeffrey; Grebe, Kristie; Shenderov, Eugene; Peters, Bjoern; Chen, Qiongyu; Peng, YanChun; Wang, Lili; Dong, Tao; Pasquetto, Valerie; Osroff, Carla; Sidney, John; Hickman, Heather; Cerundolo, Vincenzo; Sette, Alessandro; Bennink, Jack R.; McMchael, Andrew; Yewdell, Jonathan W.

    2009-01-01

    Quantitating the frequency of T cell cross-reactivity to unrelated peptides is essential to understanding T cell responses in infectious and autoimmune diseases. Here we used 15 mouse or human CD8+ T cell clones (11 antiviral, 4 anti-self) in conjunction with a large library of defined synthetic peptides to examine nearly 30,000 TCR-peptide MHC class I interactions for cross-reactions. We identified a single cross-reaction consisting of an anti-self TCR recognizing a poxvirus peptide at relatively low sensitivity. We failed to identify any cross-reactions between the synthetic peptides in the panel and polyclonal CD8+ T cells raised to viral or alloantigens. These findings provide the best estimate to date of the frequency of T cell cross-reactivity to unrelated peptides (∼1/30,000), explaining why cross-reactions between unrelated pathogens are infrequently encountered and providing a critical parameter for understanding the scope of self-tolerance. PMID:19734234

  17. Well-Defined Models for the Elusive Dinuclear Intermediates of the Pauson-Khand Reaction.

    PubMed

    Hartline, Douglas R; Zeller, Matthias; Uyeda, Christopher

    2016-05-10

    The mechanism of the Pauson-Khand reaction has attracted significant interest due to the unusual dinuclear nature of the Co2 (CO)x active site. Experimental and computational data have indicated that the intermediates following the initial Co2 (CO)6 (alkyne) complex are thermodynamically unstable and do not build up in appreciable concentrations during the course of the reaction. As a consequence, the key steps that control the scope of viable substrates and various aspects of selectivity have remained largely uncharacterized. Herein, a direct experimental investigation of the dinuclear metallacycle-forming step of the Pauson-Khand reaction is reported. These studies capitalize on well-defined d(9) -d(9) dinickel complexes supported by a naphthyridine-diimine (NDI) pincer ligand as functional surrogates of Co2 (CO)8 . © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Pyro-Synthesis of Functional Nanocrystals

    PubMed Central

    Gim, Jihyeon; Mathew, Vinod; Lim, Jinsub; Song, Jinju; Baek, Sora; Kang, Jungwon; Ahn, Docheon; Song, Sun-Ju; Yoon, Hyeonseok; Kim, Jaekook

    2012-01-01

    Despite nanomaterials with unique properties playing a vital role in scientific and technological advancements of various fields including chemical and electrochemical applications, the scope for exploration of nano-scale applications is still wide open. The intimate correlation between material properties and synthesis in combination with the urgency to enhance the empirical understanding of nanomaterials demand the evolution of new strategies to promising materials. Herein we introduce a rapid pyro-synthesis that produces highly crystalline functional nanomaterials under reaction times of a few seconds in open-air conditions. The versatile technique may facilitate the development of a variety of nanomaterials and, in particular, carbon-coated metal phosphates with appreciable physico-chemical properties benefiting energy storage applications. The present strategy may present opportunities to develop “design rules” not only to produce nanomaterials for various applications but also to realize cost-effective and simple nanomaterial production beyond lab-scale limitations. PMID:23230511

  19. Oxygen-Controlled Catalysis by Vitamin B12 -TiO2 : Formation of Esters and Amides from Trichlorinated Organic Compounds by Photoirradiation.

    PubMed

    Shimakoshi, Hisashi; Hisaeda, Yoshio

    2015-12-14

    An oxygen switch in catalysis of the cobalamin derivative (B12 )-TiO2 hybrid catalyst for the dechlorination of trichlorinated organic compounds has been developed. The covalently bound B12 on the TiO2 surface transformed trichlorinated organic compounds into an ester and amide by UV light irradiation under mild conditions (in air at room temperature), while dichlorostilbenes (E and Z forms) were formed in nitrogen from benzotrichloride. A benzoyl chloride was formed as an intermediate of the ester and amide, which was detected by GC-MS. The substrate scope of the synthetic strategy is demonstrated with a range of various trichlorinated organic compounds. A photo-duet reaction utilizing the hole and conduction band electron of TiO2 in B12 -TiO2 for the amide formation was also developed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Pyro-synthesis of functional nanocrystals.

    PubMed

    Gim, Jihyeon; Mathew, Vinod; Lim, Jinsub; Song, Jinju; Baek, Sora; Kang, Jungwon; Ahn, Docheon; Song, Sun-Ju; Yoon, Hyeonseok; Kim, Jaekook

    2012-01-01

    Despite nanomaterials with unique properties playing a vital role in scientific and technological advancements of various fields including chemical and electrochemical applications, the scope for exploration of nano-scale applications is still wide open. The intimate correlation between material properties and synthesis in combination with the urgency to enhance the empirical understanding of nanomaterials demand the evolution of new strategies to promising materials. Herein we introduce a rapid pyro-synthesis that produces highly crystalline functional nanomaterials under reaction times of a few seconds in open-air conditions. The versatile technique may facilitate the development of a variety of nanomaterials and, in particular, carbon-coated metal phosphates with appreciable physico-chemical properties benefiting energy storage applications. The present strategy may present opportunities to develop "design rules" not only to produce nanomaterials for various applications but also to realize cost-effective and simple nanomaterial production beyond lab-scale limitations.

  1. Building A Collaborative And Distributed E&O Program For EarthScope

    NASA Astrophysics Data System (ADS)

    Hall-Wallace, M. K.; Boyd, T.; Richard, G.; Ellins, K.; Meertens, C.; Semken, S.; Taber, J.; Benthien, M.; Wald, L.; Marvinney, R.

    2003-12-01

    EarthScope's education and outreach (E&O) mission is to ensure that the EarthScope experiment creates as its legacy a public more knowledgeable and understanding of the scientific and societal contributions made by the EarthScope experiment and Earth science. It will fulfill this commitment by developing and disseminating programs and products that utilize the data, models, technology and discoveries of EarthScope. The EarthScope Education and Outreach Network (EON), consisting of local EON alliances, the EarthScope facilities, partner organizations and a coordinating office, will facilitate this E&O mission. The local EON alliances, which will vary in size and purpose to respond quickly and to meet the specific needs in a region, will carry out the bulk of the effort. Thus, EarthScope EON can provide customized services that engage culturally, economically and geographically diverse audiences at the national and local scales. The EarthScope facilities and research community will provide access to data, models, and visualization tools for educational purposes. Partnerships with other national and local science education and outreach programs at colleges, universities, research facilities and professional societies within the EarthScope community as well as relevant programs at museums and parks, state geologic surveys and emergency management agencies, and K-12 schools are critical to EON's success. These partnerships will allow EON to use existing resources, networks and expertise to gear up quickly and efficiently. As EON develops, it will reciprocate by contributing new resources and expertise to the partnerships that help improve public understanding of Earth systems overall and promote effective application of EarthScope discoveries. In this presentation, we will outline major programs and products envisioned for EarthScope, plans for evaluating those programs locally and nationally, and mechanisms for collaborating with existing E&O programs.

  2. A review of the Virginia Department of Transportation's scoping process and options for potential improvements.

    DOT National Transportation Integrated Search

    2008-01-01

    Transportation project scoping is a process where the project's purpose and need, budget, schedule, and scope are developed. Interviews conducted with 27 staff representing VDOT, FHWA, and regional planners, coupled with a review of related literatur...

  3. 48 CFR 713.000 - Scope of part.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Scope of part. 713.000 Section 713.000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES SIMPLIFIED ACQUISITION PROCEDURES 713.000 Scope of part. The simplified...

  4. 48 CFR 713.000 - Scope of part.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Scope of part. 713.000 Section 713.000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES SIMPLIFIED ACQUISITION PROCEDURES 713.000 Scope of part. The simplified...

  5. 7 CFR 1924.103 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Scope. 1924.103 Section 1924.103 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... CONSTRUCTION AND REPAIR Planning and Performing Site Development Work § 1924.103 Scope. This subpart provides...

  6. Remote-controlling chemical reactions by light: towards chemistry with high spatio-temporal resolution.

    PubMed

    Göstl, Robert; Senf, Antti; Hecht, Stefan

    2014-03-21

    The foundation of the chemical enterprise has always been the creation of new molecular entities, such as pharmaceuticals or polymeric materials. Over the past decades, this continuing effort of designing compounds with improved properties has been complemented by a strong effort to render their preparation (more) sustainable by implementing atom as well as energy economic strategies. Therefore, synthetic chemistry is typically concerned with making specific bonds and connections in a highly selective and efficient manner. However, to increase the degree of sophistication and expand the scope of our work, we argue that the modern aspiring chemist should in addition be concerned with attaining (better) control over when and where chemical bonds are being made or broken. For this purpose, photoswitchable molecular systems, which allow for external modulation of chemical reactions by light, are being developed and in this review we are covering the current state of the art of this exciting new field. These "remote-controlled synthetic tools" provide a remarkable opportunity to perform chemical transformations with high spatial and temporal resolution and should therefore allow regulating biological processes as well as material and device performance.

  7. Investigations of Scope and Mechanism of Nickel-Catalyzed Transformations of Glycosyl Trichloroacetimidates to Glycosyl Trichloroacetamides and Subsequent, Atom-Economical, One-Step Conversion to α-Urea-Glycosides

    PubMed Central

    McKay, Matthew J.; Park, Nathaniel H.; Nguyen, Hien M.

    2014-01-01

    The development and mechanistic investigation of a highly stereoselective methodology for preparing α-linked-urea neo-glycoconjugates and pseudo-oligosaccharides is described. This two-step procedure begins with the selective nickel-catalyzed conversion of glycosyl trichloroacetimidates to the corresponding α-trichloroacetamides. The α-selective nature of the conversion is controlled with a cationic nickel(II) catalyst, Ni(dppe)(OTf)2. Mechanistic studies have identified the coordination of the nickel catalyst with the equatorial C2-ether functionality of the α-glycosyl trichloroacetimidate to be paramount for achieving an α-stereoselective transformation. A cross-over experiment has indicated that the reaction does not proceed in an exclusively-intramolecular fashion. The second step in this sequence is the direct conversion of α-glycosyl trichloroacetamide products into the corresponding α-urea glycosides by reacting them with a wide variety of amine nucleophiles in presence of cesium carbonate. Only α-urea-product formation is observed, as the reaction proceeds with complete retention of stereochemical integrity at the anomeric C-N bond. PMID:24905328

  8. 10 CFR 473.1 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Purpose and scope. 473.1 Section 473.1 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION AUTOMOTIVE PROPULSION RESEARCH AND DEVELOPMENT Review and Certification of Grants, Cooperative Agreements, Contracts, and Projects § 473.1 Purpose and scope. These...

  9. 10 CFR 473.1 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Purpose and scope. 473.1 Section 473.1 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION AUTOMOTIVE PROPULSION RESEARCH AND DEVELOPMENT Review and Certification of Grants, Cooperative Agreements, Contracts, and Projects § 473.1 Purpose and scope. These...

  10. 10 CFR 473.1 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Purpose and scope. 473.1 Section 473.1 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION AUTOMOTIVE PROPULSION RESEARCH AND DEVELOPMENT Review and Certification of Grants, Cooperative Agreements, Contracts, and Projects § 473.1 Purpose and scope. These...

  11. 10 CFR 473.1 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Purpose and scope. 473.1 Section 473.1 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION AUTOMOTIVE PROPULSION RESEARCH AND DEVELOPMENT Review and Certification of Grants, Cooperative Agreements, Contracts, and Projects § 473.1 Purpose and scope. These...

  12. 10 CFR 473.1 - Purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Purpose and scope. 473.1 Section 473.1 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION AUTOMOTIVE PROPULSION RESEARCH AND DEVELOPMENT Review and Certification of Grants, Cooperative Agreements, Contracts, and Projects § 473.1 Purpose and scope. These...

  13. 48 CFR 749.100 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Scope of subpart. 749.100 Section 749.100 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT TERMINATION OF CONTRACTS General Principles 749.100 Scope of subpart. The Foreign Aid and Related...

  14. Workforce Trends, Workplace Trends: How They Dictate a Changing Education and Training Strategy.

    ERIC Educational Resources Information Center

    Plewes, Thomas J.

    Four trends will alter the way the education and training system and other human resource agencies will do business. Themes that reflect them are captured in four words: flexibility, quality, diversity, and scope. The reaction to the current economic downturn remains one of flexibility. Flexibility has emerged as the way in which employers look at…

  15. Regioselective 5-exo-dig oxy-cyclization of 2-alkynylbenzamide for the synthesis of isobenzofuran-1-imines and isobenzofuran.

    PubMed

    Wang, Rui-Xiang; Yuan, Si-Tian; Liu, Jin-Biao; Wu, Jie; Qiu, Guanyinsheng

    2018-06-06

    A TBAB-mediated brominative 5-exo-dig oxy-cyclization of 2-alkynylbenzamide is described here for the synthesis of isobenzofuran-1-imines and isobenzofuran derivatives at room temperature with a high efficiency and a broad reaction scope. The resulting isobenzofuran derivatives are also applied for synthesising various substituted isobenzofuran derivatives.

  16. A dual-catalysis approach to enantioselective [2 + 2] photocycloadditions using visible light.

    PubMed

    Du, Juana; Skubi, Kazimer L; Schultz, Danielle M; Yoon, Tehshik P

    2014-04-25

    In contrast to the wealth of catalytic systems that are available to control the stereochemistry of thermally promoted cycloadditions, few similarly effective methods exist for the stereocontrol of photochemical cycloadditions. A major unsolved challenge in the design of enantioselective catalytic photocycloaddition reactions has been the difficulty of controlling racemic background reactions that occur by direct photoexcitation of substrates while unbound to catalyst. Here, we describe a strategy for eliminating the racemic background reaction in asymmetric [2 + 2] photocycloadditions of α,β-unsaturated ketones to the corresponding cyclobutanes by using a dual-catalyst system consisting of a visible light-absorbing transition-metal photocatalyst and a stereocontrolling Lewis acid cocatalyst. The independence of these two catalysts enables broader scope, greater stereochemical flexibility, and better efficiency than previously reported methods for enantioselective photochemical cycloadditions.

  17. Lanthanum Tricyanide-Catalyzed Acyl Silane-Ketone Benzoin Additions and Kinetic Resolution of Resultant α-Silyloxyketones

    PubMed Central

    Tarr, James C.

    2010-01-01

    We report the full account of our efforts on the lanthanum tricyanide-catalyzed acyl silane-ketone benzoin reaction. The reaction exhibits a wide scope in both acyl silane (aryl, alkyl) and ketone (aryl-alkyl, alkyl-alkyl, aryl-aryl, alkenyl-alkyl, alkynyl-alkyl) coupling partners. The diastereoselectivity of the reaction has been examined in both cyclic and acyclic systems. Cyclohexanones give products arising from equatorial attack by the acyl silane. The diastereoselectivity of acyl silane addition to acyclic α-hydroxy ketones can be controlled by varying the protecting group to obtain either Felkin-Ahn or chelation control. The resultant α-silyloxyketone products can be resolved with selectivity factors from 10 to 15 by subjecting racemic ketone benzoin products to CBS reduction. PMID:20392127

  18. 24 CFR 246.1 - Scope and effect of regulations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Scope and effect of regulations. 246.1 Section 246.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF...

  19. 24 CFR 246.1 - Scope and effect of regulations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Scope and effect of regulations. 246.1 Section 246.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF...

  20. 24 CFR 246.1 - Scope and effect of regulations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Scope and effect of regulations. 246.1 Section 246.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF...

  1. 24 CFR 246.1 - Scope and effect of regulations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Scope and effect of regulations. 246.1 Section 246.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF...

  2. 24 CFR 246.1 - Scope and effect of regulations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Scope and effect of regulations. 246.1 Section 246.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF...

  3. Cosmetology: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for a cosmetology vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed by teachers, parents, and the…

  4. Aircraft Mechanics: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for an aircraft mechanics vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed by teachers, parents, and…

  5. Mechanism and scope of the cyanide-catalyzed cross silyl benzoin reaction.

    PubMed

    Linghu, Xin; Bausch, Cory C; Johnson, Jeffrey S

    2005-02-16

    In this work, cross silyl benzoin addition reactions between acylsilanes (1) and aldehydes (2) catalyzed by metal cyanides are described. Unsymmetrical aryl-, heteroaryl-, and alkyl-substituted benzoin adducts can be generated in moderate to excellent yields with complete regiocontrol using potassium cyanide and a phase transfer catalyst. From a screen of transition metal cyanide complexes, lanthanum tricyanide was identified as an improved second-generation catalyst for the cross silyl benzoin reaction. A study of the influence of water on the KCN-catalyzed cross silyl benzoin addition revealed more practical reaction conditions using unpurified solvent under ambient conditions. A sequential silyl benzoin addition/cyanation/O-acylation reaction that resulted in two new C-C bonds was achieved in excellent yield. The mechanism of cross silyl benzoin addition is proposed in detail and is supported by crossover studies and a number of unambiguous experiments designed to ascertain the reversibility of key steps. No productive chemistry arises from cyanation of the more electrophilic aldehyde component. Formation of the carbon-carbon bond is shown to be the last irreversible step in the reaction.

  6. 25 CFR 224.66 - How may a tribe reduce the scope of the TERA?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ENERGY RESOURCE AGREEMENTS UNDER THE INDIAN TRIBAL ENERGY DEVELOPMENT AND SELF DETERMINATION ACT... development managed under the TERA. Any such reduction in scope must include the return of all relevant...

  7. Enantioselective Bronsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes

    NASA Astrophysics Data System (ADS)

    Gheewala, Chirag

    This thesis details the design and development of pentacarboxycyclopentadienes (PCCPs) as a new platform for enantioselective Bronsted acid catalysis. Prior to this research, enantioselective Bronsted acid catalysis was limited to the BINOL (and variations thereof) framework. While this catalyst platform has paved the way for a myriad of novel asymmetric chemical transformations, the utility of this catalyst scaffold has suffered from its lengthy and expensive preparations. As an alternative, starting from readily available 1,2,3,4,5-pentacarbomethoxycyclopentadiene and various chiral alcohols and amines, the synthesis of a library of strongly acidic chiral catalysts is described. The utility of these novel acid catalysts is explored in various transformations. As a prelude to the heart of this work, Chapter 1 focuses on the advancements made in asymmetric Bronsted acid catalysis through BINOL-phosphate derived catalysts, focusing on the major accomplishments made by researchers since 2004. The provided review highlights the utility of these chiral acid catalysts but also reveals the need for a new scaffold that is more affordable and accessible. Chapter 2 discusses the background of PCCPs, including its initial discovery and subsequent applications. Our work in developing novel transesterified and amidated derivatives is discussed with accompanying crystal structures of achiral and chiral PCCPs. pKa measurements demonstrate the capacity of PCCPs to be used as strong Bronsted acid catalysts and are compared to literature values of known Bronsted acid catalysts. Chapter 3 focuses on the utility of PCCPs as enantioselective Bronsted acid catalysts in a variety of chemical transformations including the Mukaiyama-Mannich reaction, transfer hydrogenation, Pictet-Spengler reaction, diaryl alcohol substitution, Mukayaiama oxocarbenium aldol reaction, and [4+2]-cycloaddition. Catalyst loadings down to 0.01 mol% and reaction scale up to 25 grams in the Mukaiyama-Mannich reaction demonstrate the practical utility and robustness of PCCPs. Substrate scopes of these transformations show the breadth of accessible molecules that can be synthesized via PCCPs. Mechanistic rationales and transition state analyses are discussed in each of the transformations.

  8. A continuous-flow capillary mixing method to monitor reactions on the microsecond time scale.

    PubMed Central

    Shastry, M C; Luck, S D; Roder, H

    1998-01-01

    A continuous-flow capillary mixing apparatus, based on the original design of Regenfuss et al. (Regenfuss, P., R. M. Clegg, M. J. Fulwyler, F. J. Barrantes, and T. M. Jovin. 1985. Rev. Sci. Instrum. 56:283-290), has been developed with significant advances in mixer design, detection method and data analysis. To overcome the problems associated with the free-flowing jet used for observation in the original design (instability, optical artifacts due to scattering, poor definition of the geometry), the solution emerging from the capillary is injected directly into a flow-cell joined to the tip of the outer capillary via a ground-glass joint. The reaction kinetics are followed by measuring fluorescence versus distance downstream from the mixer, using an Hg(Xe) arc lamp for excitation and a digital camera with a UV-sensitized CCD detector for detection. Test reactions involving fluorescent dyes indicate that mixing is completed within 15 micros of its initiation and that the dead time of the measurement is 45 +/- 5 micros, which represents a >30-fold improvement in time resolution over conventional stopped-flow instruments. The high sensitivity and linearity of the CCD camera have been instrumental in obtaining artifact-free kinetic data over the time window from approximately 45 micros to a few milliseconds with signal-to-noise levels comparable to those of conventional methods. The scope of the method is discussed and illustrated with an example of a protein folding reaction. PMID:9591695

  9. Rapid End-Group Modification of Polysaccharides for Biomaterial Applications in Regenerative Medicine.

    PubMed

    Bondalapati, Somasekhar; Ruvinov, Emil; Kryukov, Olga; Cohen, Smadar; Brik, Ashraf

    2014-09-15

    Polysaccharides have emerged as important functional materials because of their unique properties such as biocompatibility, biodegradability, and availability of reactive sites for chemical modifications to optimize their properties. The overwhelming majority of the methods to modify polysaccharides employ random chemical modifications, which often improve certain properties while compromising others. On the other hand, the employed methods for selective modifications often require excess of coupling partners, long reaction times and are limited in their scope and wide applicability. To circumvent these drawbacks, aniline-catalyzed oxime formation is developed for selective modification of a variety of polysaccharides through their reducing end. Notably, it is found that for efficient oxime formation, different conditions are required depending on the composition of the specific polysaccharide. It is also shown how our strategy can be applied to improve the physical and functional properties of alginate hydrogels, which are widely used in tissue engineering and regenerative medicine applications. While the randomly and selectively modified alginate exhibits similar viscoelastic properties, the latter forms significantly more stable hydrogel and superior cell adhesive and functional properties. Our results show that the developed conjugation reaction is robust and should open new opportunities for preparing polysaccharide-based functional materials with unique properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. 48 CFR 750.000 - Scope of part.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Scope of part. 750.000 Section 750.000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS 750.000 Scope of part. USAID is not among the agencies named in...

  11. 48 CFR 750.000 - Scope of part.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Scope of part. 750.000 Section 750.000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS 750.000 Scope of part. USAID is not among the agencies named in...

  12. 48 CFR 750.000 - Scope of part.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Scope of part. 750.000 Section 750.000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS 750.000 Scope of part. USAID is not among the agencies named in...

  13. Exploring extended scope of practice in dietetics: A systems approach.

    PubMed

    Ryan, Dominique; Pelly, Fiona; Purcell, Elizabeth

    2017-09-01

    The aim of this study was to explore health professionals' perceptions of an extended scope of a practice clinic, and develop a framework using a systems approach to facilitate extended scope models across various health settings. A qualitative investigation using semi-structured interviews with four health professionals involved in an extended scope dietitian-led gastroenterology clinic in a hospital in regional Queensland was conducted. A case study design was utilised to investigate interviewees' perceptions of the clinic. Participants were conveniently, purposively sampled. Transcript analysis involved a descriptive analytical approach. Interviewee responses were coded and categorised into themes, and investigator triangulation was used to ensure consistency between individual analyses. A secondary interpretative analysis was conducted where relationships between key themes were mapped to the Systems Engineering Initiative for Patient Safety work system model. Interviewees identified various factors as vital inputs to the work system. These were categorised into the four key elements: stakeholder support, resources, planning and the dietitian. Clinic outcomes were categorised into the impact on four key groups: patients, the dietitian, the multidisciplinary team and the health system. Mapping of the relationships between inputs and outcomes resulted in an implementation framework for extended scope of practice. Extended scope of practice in dietetics may provide positive outcomes for various stakeholders. However, further development of extended scope roles for dietitians requires increased advocacy and support from governments, professional bodies, training institutions and dietitians. We have developed an implementation framework which can be utilised by health professionals interested in embracing an extended scope model of care. © 2016 Dietitians Association of Australia.

  14. Auto Mechanics: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for an auto mechanics vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed by teachers, parents, and the…

  15. 24 CFR 941.101 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... housing residents over the long term and have the lowest possible life cycle costs, taking into account... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Purpose and scope. 941.101 Section 941.101 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued...

  16. Diesel Mechanics: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for a diesel mechanics vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed by teachers, parents, and the…

  17. 24 CFR 984.101 - Purpose, scope, and applicability.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT SECTION 8 AND PUBLIC HOUSING FAMILY SELF-SUFFICIENCY PROGRAM General § 984.101 Purpose... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Purpose, scope, and applicability. 984.101 Section 984.101 Housing and Urban Development Regulations Relating to Housing and Urban...

  18. 24 CFR 85.2 - Scope of subpart.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Scope of subpart. 85.2 Section 85.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND FEDERALLY RECOGNIZED INDIAN...

  19. 24 CFR 85.2 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Scope of subpart. 85.2 Section 85.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND FEDERALLY RECOGNIZED INDIAN...

  20. 24 CFR 85.1 - Purpose and scope of this part.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Purpose and scope of this part. 85.1 Section 85.1 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND...

  1. 24 CFR 85.1 - Purpose and scope of this part.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Purpose and scope of this part. 85.1 Section 85.1 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND...

  2. 24 CFR 85.1 - Purpose and scope of this part.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Purpose and scope of this part. 85.1 Section 85.1 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND...

  3. 24 CFR 85.2 - Scope of subpart.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Scope of subpart. 85.2 Section 85.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND FEDERALLY RECOGNIZED INDIAN...

  4. 24 CFR 85.2 - Scope of subpart.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Scope of subpart. 85.2 Section 85.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND FEDERALLY RECOGNIZED INDIAN...

  5. 24 CFR 85.1 - Purpose and scope of this part.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Purpose and scope of this part. 85.1 Section 85.1 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND...

  6. 24 CFR 85.1 - Purpose and scope of this part.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Purpose and scope of this part. 85.1 Section 85.1 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND...

  7. 24 CFR 85.2 - Scope of subpart.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Scope of subpart. 85.2 Section 85.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE, LOCAL AND FEDERALLY RECOGNIZED INDIAN...

  8. Air Conditioning, Heating, and Refrigeration: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for an air conditioning, heating, and refrigeration vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed…

  9. Commercial Art: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for a commercial art vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed by teachers, parents, and the…

  10. 24 CFR 4000.1 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Purpose and scope. 4000.1 Section 4000.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) BOARD OF DIRECTORS OF THE HOPE FOR HOMEOWNERS PROGRAM BOARD OF DIRECTORS OF THE HOPE FOR HOMEOWNERS...

  11. 24 CFR 17.100 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Scope. 17.100 Section 17.100 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development... to debts arising under the Internal Revenue Code of 1954 (26 U.S.C. 1-9602), the Social Security Act...

  12. Flow chemistry: intelligent processing of gas-liquid transformations using a tube-in-tube reactor.

    PubMed

    Brzozowski, Martin; O'Brien, Matthew; Ley, Steven V; Polyzos, Anastasios

    2015-02-17

    CONSPECTUS: The previous decade has witnessed the expeditious uptake of flow chemistry techniques in modern synthesis laboratories, and flow-based chemistry is poised to significantly impact our approach to chemical preparation. The advantages of moving from classical batch synthesis to flow mode, in order to address the limitations of traditional approaches, particularly within the context of organic synthesis are now well established. Flow chemistry methodology has led to measurable improvements in safety and reduced energy consumption and has enabled the expansion of available reaction conditions. Contributions from our own laboratories have focused on the establishment of flow chemistry methods to address challenges associated with the assembly of complex targets through the development of multistep methods employing supported reagents and in-line monitoring of reaction intermediates to ensure the delivery of high quality target compounds. Recently, flow chemistry approaches have addressed the challenges associated with reactions utilizing reactive gases in classical batch synthesis. The small volumes of microreactors ameliorate the hazards of high-pressure gas reactions and enable improved mixing with the liquid phase. Established strategies for gas-liquid reactions in flow have relied on plug-flow (or segmented flow) regimes in which the gas plugs are introduced to a liquid stream and dissolution of gas relies on interfacial contact of the gas bubble with the liquid phase. This approach confers limited control over gas concentration within the liquid phase and is unsuitable for multistep methods requiring heterogeneous catalysis or solid supported reagents. We have identified the use of a gas-permeable fluoropolymer, Teflon AF-2400, as a simple method of achieving efficient gas-liquid contact to afford homogeneous solutions of reactive gases in flow. The membrane permits the transport of a wide range of gases with significant control of the stoichiometry of reactive gas in a given reaction mixture. We have developed a tube-in-tube reactor device consisting of a pair of concentric capillaries in which pressurized gas permeates through an inner Teflon AF-2400 tube and reacts with dissolved substrate within a liquid phase that flows within a second gas impermeable tube. This Account examines our efforts toward the development of a simple, unified methodology for the processing of gaseous reagents in flow by way of development of a tube-in-tube reactor device and applications to key C-C, C-N, and C-O bond forming and hydrogenation reactions. We further describe the application to multistep reactions using solid-supported reagents and extend the technology to processes utilizing multiple gas reagents. A key feature of our work is the development of computer-aided imaging techniques to allow automated in-line monitoring of gas concentration and stoichiometry in real time. We anticipate that this Account will illustrate the convenience and benefits of membrane tube-in-tube reactor technology to improve and concomitantly broaden the scope of gas/liquid/solid reactions in organic synthesis.

  13. Highly efficient regioselective synthesis, spectroscopic characterizations and DFT calculations of novel hydroxymethylated 1,4-disubstituted-1,2,3-triazole-based sulfonamides

    NASA Astrophysics Data System (ADS)

    Taheri, Elmira; Mirjafary, Zohreh; Saeidian, Hamid

    2018-04-01

    The novel hydroxymethylated 1,4-disubstituted-1,2,3-triazole-based sulfonamides were synthesized in excellent yields and high regioselectivity via a one-pot, two-step, three-component reaction of N-propargylsulfonamides, sodium azide, and epoxide derivatives under green conditions. Green and mild reaction condition, commercially readily available and inexpensive starting materials, wide scope and easy work-up are the key features of the present method. The Li+ and Na+ ion affinities of the model structure have been also investigated by density functional theory (DFT) studies to find the applicability of these products as ligand in coordination chemistry.

  14. Teaching Old Compounds New Tricks: DDQ-Photocatalyzed C-H Amination of Arenes with Carbamates, Urea, and N-Heterocycles.

    PubMed

    Das, Somnath; Natarajan, Palani; König, Burkhard

    2017-12-22

    The C-H amination of benzene derivatives was achieved using DDQ as photocatalyst and BocNH 2 as the amine source under aerobic conditions and visible light irradiation. Electron-deficient and electron-rich benzenes react as substrates with moderate to good product yields. The amine scope of the reaction comprises Boc-amine, carbamates, pyrazoles, sulfonimides and urea. Preliminary mechanistic investigations indicate arene oxidation by the triplet of DDQ to radical cations with different electrophilicity and a charge transfer complex between the amine and DDQ as intermediate of the reaction. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Halogenase engineering and its utility in medicinal chemistry.

    PubMed

    Fraley, Amy E; Sherman, David H

    2018-06-15

    Halogenation is commonly used in medicinal chemistry to improve the potency of pharmaceutical leads. While synthetic methods for halogenation present selectivity and reactivity challenges, halogenases have evolved over time to perform selective reactions under benign conditions. The optimization of halogenation biocatalysts has utilized enzyme evolution and structure-based engineering alongside biotransformation in a variety of systems to generate stable site-selective variants. The recent improvements in halogenase-catalyzed reactions has demonstrated the utility of these biocatalysts for industrial purposes, and their ability to achieve a broad substrate scope implies a synthetic tractability with increasing relevance in medicinal chemistry. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. A Mild, Ferrocene-Catalyzed C–H Imidation of (Hetero)Arenes

    PubMed Central

    2015-01-01

    A simple method for direct C–H imidation is reported using a new perester-based self-immolating reagent and a base-metal catalyst. The succinimide products obtained can be easily deprotected in situ (if desired) to reveal the corresponding anilines directly. The scope of the reaction is broad, the conditions are extremely mild, and the reaction is tolerant of oxidizable and acid-labile functionality, multiple heteroatoms, and aryl iodides. Mechanistic studies indicate that ferrocene (Cp2Fe) plays the role of an electron shuttle in the decomposition of the perester reagent, delivering a succinimidyl radical ready to add to an aromatic system. PMID:24654983

  17. Using the written description requirement to limit broad patent scope, allow competition, and encourage innovation in biotechnology.

    PubMed

    Mull, William C

    2004-01-01

    The biotechnology research and development process is extremely expensive and companies must attract investors to this high-risk industry to pay for these costs. Biotechnology companies rely on their ability to exclude others from exploiting the benefits of their research through patent protection to attract these investors. Consequently, they seek strong patent protection for their inventions by claiming a broad scope of patent protection for their inventions. Biotechnology is an industry where the scope of protection should be limited. Science-based technologies exploit the perceived technological opportunities from recent scientific developments, concentrating the attention of many inventors on the same areas. This poses several unique problems. First, only the first of several inventors will receive a patent to the invention. Second, due to publicly available, basic techniques, the actual contribution made by the inventor may be relatively small. Finally, there is a significant risk that permitting an overbroad patent scope may permit original patentees to control a variety of improvements and a number of applications. Additionally, a broad scope of protection for an invention tends to cause underutilization of many potential inventions or improvements. By limiting the scope of protection, one allows competitors to utilize these potential inventions or improvements and encourages the advancement of the technology. Traditionally, courts have used the scope of the disclosure to limit a patent with an overly broad scope of protection. The Federal Circuit is correctly applying the written description requirement as part of the disclosure to limit broad claim scope in biotechnology patents. The written description requirement is separate from the enablement requirement and applies to all claims. By requiring a written description to allow a PHOSITA to determine the structural characteristics of the claimed invention, the Federal Circuit is able limit biotechnology patents with overly broad patent scope. Recognizing that particular technologies will become more established as biotechnology matures giving rise to different issues in setting the appropriate level of patent scope, the court allowed the written description requirement to mature in tandem with advances in biotechnology to meet these new developments.

  18. 48 CFR 753.300 - Scope of subpart.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Scope of subpart. 753.300 Section 753.300 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CLAUSES AND FORMS FORMS Illustration of Forms 753.300 Scope of subpart. USAID forms are not illustrated in the AIDAR...

  19. 48 CFR 753.300 - Scope of subpart.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Scope of subpart. 753.300 Section 753.300 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CLAUSES AND FORMS FORMS Illustration of Forms 753.300 Scope of subpart. USAID forms are not illustrated in the AIDAR...

  20. 22 CFR 215.1 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Purpose and scope. 215.1 Section 215.1 Foreign... Purpose and scope. (a) It is the purpose and objective of the International Development Cooperation Agency... procedures by which an individual may obtain notification of the existence of Agency records pertaining to...

  1. 22 CFR 215.1 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Purpose and scope. 215.1 Section 215.1 Foreign... Purpose and scope. (a) It is the purpose and objective of the International Development Cooperation Agency... procedures by which an individual may obtain notification of the existence of Agency records pertaining to...

  2. Orion GN&C Fault Management System Verification: Scope And Methodology

    NASA Technical Reports Server (NTRS)

    Brown, Denise; Weiler, David; Flanary, Ronald

    2016-01-01

    In order to ensure long-term ability to meet mission goals and to provide for the safety of the public, ground personnel, and any crew members, nearly all spacecraft include a fault management (FM) system. For a manned vehicle such as Orion, the safety of the crew is of paramount importance. The goal of the Orion Guidance, Navigation and Control (GN&C) fault management system is to detect, isolate, and respond to faults before they can result in harm to the human crew or loss of the spacecraft. Verification of fault management/fault protection capability is challenging due to the large number of possible faults in a complex spacecraft, the inherent unpredictability of faults, the complexity of interactions among the various spacecraft components, and the inability to easily quantify human reactions to failure scenarios. The Orion GN&C Fault Detection, Isolation, and Recovery (FDIR) team has developed a methodology for bounding the scope of FM system verification while ensuring sufficient coverage of the failure space and providing high confidence that the fault management system meets all safety requirements. The methodology utilizes a swarm search algorithm to identify failure cases that can result in catastrophic loss of the crew or the vehicle and rare event sequential Monte Carlo to verify safety and FDIR performance requirements.

  3. Evolution of C−H Bond Functionalization from Methane to Methodology

    PubMed Central

    2016-01-01

    This Perspective presents the fundamental principles, the elementary reactions, the initial catalytic systems, and the contemporary catalysts that have converted C−H bond functionalization from a curiosity to a reality for synthetic chemists. Many classes of elementary reactions involving transition-metal complexes cleave C−H bonds at typically unreactive positions. These reactions, coupled with a separate or simultaneous functionalization process lead to products containing new C−C, C−N, and C−O bonds. Such reactions were initially studied for the conversion of light alkanes to liquid products, but they have been used (and commercialized in some cases) most often for the synthesis of the more complex structures of natural products, medicinally active compounds, and aromatic materials. Such a change in direction of research in C−H bond functionalization is remarkable because the reactions must occur at an unactivated C−H bond over functional groups that are more reactive than the C−H bond toward classical reagents. The scope of reactions that form C−C bonds or install functionality at an unactivated C−H bond will be presented, and the potential future utility of these reactions will be discussed. PMID:26566092

  4. Microwave promoted simple, efficient and regioselective synthesis of trisubstituted imidazo[1,2-a]benzimidazoles on soluble support.

    PubMed

    Chen, Li-Hsun; Hsiao, Ya-Shan; Yellol, Gorakh S; Sun, Chung-Ming

    2011-03-14

    An efficient microwave-assisted and soluble polymer-supported synthesis of medicinally important imidazole-fused benzimidazoles has been developed. The protocol involves the rapid condensation of polymer-bound amino benzimidazoles with various α-bromoketones and subsequent in situ intramolecular cyclization under microwave irradiation resulting in a one pot synthesis of imidazole interlacing benzimidazole polymer conjugates. The condensed product was obtained with excellent regioselectivity. The biologically interesting imidazo[1,2-a]benzimidazoles was released from polymer support at ambient temperature. Diversity in the triheterocyclic nucleus was achieved by the different substitutions at its 2, 3, and 9 positions. The new protocol has the advantages of short reaction time, easy workup process, excellent yields, reduced environmental impact, wide substrate scope and convenient procedure.

  5. SnAP reagents for the one-step synthesis of medium-ring saturated N-heterocycles from aldehydes

    NASA Astrophysics Data System (ADS)

    Vo, Cam-Van T.; Luescher, Michael U.; Bode, Jeffrey W.

    2014-04-01

    Interest in saturated N-heterocycles as scaffolds for the synthesis of bioactive molecules is increasing. Reliable and predictable synthetic methods for the preparation of these compounds, especially medium-sized rings, are limited. We describe the development of SnAP (Sn amino protocol) reagents for the transformation of aldehydes into seven-, eight- and nine-membered saturated N-heterocycles. This process occurs under mild, room-temperature conditions and offers exceptional substrate scope and functional-group tolerance. Air- and moisture-stable SnAP reagents are prepared on a multigram scale from inexpensive starting materials by simple reaction sequences. These new reagents and processes allow widely available aryl, heteroaryl and aliphatic aldehydes to be converted into diverse N-heterocycles, including diazepanes, oxazepanes, diazocanes, oxazocanes and hexahydrobenzoxazonines, by a single synthetic operation.

  6. 24 CFR 1000.1 - What is the applicability and scope of these regulations?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false What is the applicability and scope of these regulations? 1000.1 Section 1000.1 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING...

  7. Metal-free, visible-light-mediated direct C-H arylation of heteroarenes with aryl diazonium salts.

    PubMed

    Hari, Durga Prasad; Schroll, Peter; König, Burkhard

    2012-02-15

    Visible light along with 1 mol % eosin Y catalyzes the direct C-H bond arylation of heteroarenes with aryl diazonium salts by a photoredox process. We have investigated the scope of the reaction for several aryl diazonium salts and heteroarenes. The general and easy procedure provides a transition-metal-free alternative for the formation of aryl-heteroaryl bonds.

  8. 14 CFR 1274.102 - Scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Scope. 1274.102 Section 1274.102 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION COOPERATIVE AGREEMENTS WITH COMMERCIAL... development; (2) Provide technology transfer from the Government to the recipient; or (3) Develop a capability...

  9. 14 CFR 1274.102 - Scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Scope. 1274.102 Section 1274.102 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION COOPERATIVE AGREEMENTS WITH COMMERCIAL... development; (2) Provide technology transfer from the Government to the recipient; or (3) Develop a capability...

  10. 48 CFR 917.7300 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 917.7300 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND CONTRACT TYPES SPECIAL CONTRACTING METHODS Program Research and Development Announcements 917.7300 Scope of subpart. (a) This subpart discusses the policy for the use of a program research and development...

  11. 24 CFR 146.11 - Scope of subpart.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 146.11 Housing and Urban Development Regulations Relating to Housing and Urban Development OFFICE OF... FINANCIAL ASSISTANCE Standards for Determining Age Discrimination § 146.11 Scope of subpart. This subpart... age that may have a disproportionate effect on persons of different ages, is prohibited. ...

  12. 13 CFR 306.1 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Purpose and scope. 306.1 Section 306.1 Business Credit and Assistance ECONOMIC DEVELOPMENT ADMINISTRATION, DEPARTMENT OF COMMERCE... throughout the nation; (2) Formulate and implement economic development tools, models, and innovative...

  13. The Identification of Children with Behavioural Manifestations of Inattention, Hyperactivity and Impulsivity, in Mainstream School: The Development of the Scope Classroom Observation Checklist

    ERIC Educational Resources Information Center

    Scope, Alison; Empson, Janet; McHale, Sue; Nabuzoka, Dabie

    2007-01-01

    The objective of this paper is to report the development and use of an observation checklist to identify typically developing children with behavioural manifestations associated with inattention, hyperactivity and impulsivity. This measure is termed the Scope Classroom Observation Checklist (SCOC). The SCOC was developed, assessed for reliability…

  14. Directed evolution of artificial metalloenzymes for in vivo metathesis

    NASA Astrophysics Data System (ADS)

    Jeschek, Markus; Reuter, Raphael; Heinisch, Tillmann; Trindler, Christian; Klehr, Juliane; Panke, Sven; Ward, Thomas R.

    2016-09-01

    The field of biocatalysis has advanced from harnessing natural enzymes to using directed evolution to obtain new biocatalysts with tailor-made functions. Several tools have recently been developed to expand the natural enzymatic repertoire with abiotic reactions. For example, artificial metalloenzymes, which combine the versatile reaction scope of transition metals with the beneficial catalytic features of enzymes, offer an attractive means to engineer new reactions. Three complementary strategies exist: repurposing natural metalloenzymes for abiotic transformations; in silico metalloenzyme (re-)design; and incorporation of abiotic cofactors into proteins. The third strategy offers the opportunity to design a wide variety of artificial metalloenzymes for non-natural reactions. However, many metal cofactors are inhibited by cellular components and therefore require purification of the scaffold protein. This limits the throughput of genetic optimization schemes applied to artificial metalloenzymes and their applicability in vivo to expand natural metabolism. Here we report the compartmentalization and in vivo evolution of an artificial metalloenzyme for olefin metathesis, which represents an archetypal organometallic reaction without equivalent in nature. Building on previous work on an artificial metallohydrolase, we exploit the periplasm of Escherichia coli as a reaction compartment for the ‘metathase’ because it offers an auspicious environment for artificial metalloenzymes, mainly owing to low concentrations of inhibitors such as glutathione, which has recently been identified as a major inhibitor. This strategy facilitated the assembly of a functional metathase in vivo and its directed evolution with substantially increased throughput compared to conventional approaches that rely on purified protein variants. The evolved metathase compares favourably with commercial catalysts, shows activity for different metathesis substrates and can be further evolved in different directions by adjusting the workflow. Our results represent the systematic implementation and evolution of an artificial metalloenzyme that catalyses an abiotic reaction in vivo, with potential applications in, for example, non-natural metabolism.

  15. 24 CFR 266.125 - Scope and nature of sanctions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Scope and nature of sanctions. 266... Housing Finance Agency Requirements § 266.125 Scope and nature of sanctions. (a) Actions by Designated Office. Depending on the nature and extent of the noncompliance with the requirements of this part, the...

  16. Literacy Teaching Aids from High/Scope Educational Research Foundation

    ERIC Educational Resources Information Center

    Science Activities: Classroom Projects and Curriculum Ideas, 2005

    2005-01-01

    High/Scope's approach to education is a blend of Jean Piaget's constructivist theory of child development and the best of traditional teacher experience. The High/Scope approach is about helping students gain knowledge and skills in important content areas, such as language and literacy, initiative and social relations, movement, music, and…

  17. 24 CFR 266.125 - Scope and nature of sanctions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Scope and nature of sanctions. 266... Housing Finance Agency Requirements § 266.125 Scope and nature of sanctions. (a) Actions by Designated Office. Depending on the nature and extent of the noncompliance with the requirements of this part, the...

  18. 24 CFR 266.125 - Scope and nature of sanctions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Scope and nature of sanctions. 266... Housing Finance Agency Requirements § 266.125 Scope and nature of sanctions. (a) Actions by Designated Office. Depending on the nature and extent of the noncompliance with the requirements of this part, the...

  19. 24 CFR 266.125 - Scope and nature of sanctions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Scope and nature of sanctions. 266... Housing Finance Agency Requirements § 266.125 Scope and nature of sanctions. (a) Actions by Designated Office. Depending on the nature and extent of the noncompliance with the requirements of this part, the...

  20. 24 CFR 266.125 - Scope and nature of sanctions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Scope and nature of sanctions. 266... Housing Finance Agency Requirements § 266.125 Scope and nature of sanctions. (a) Actions by Designated Office. Depending on the nature and extent of the noncompliance with the requirements of this part, the...

  1. A methodology for the preliminary scoping of future changes in ecosystem services, with an illustration from the future midwestern landscapes study

    EPA Science Inventory

    The product is a white paper defining a methodology for the preliminary scoping of future changes in ecosystem services, with an Illustration from the Future Midwestern Landscapes Study. The scoping method develops a hierarchy of relevant societal values, identifies the ecosyste...

  2. Innovations in making EarthScope science and data accessible (Invited)

    NASA Astrophysics Data System (ADS)

    Pratt-Sitaula, B. A.; Butler, R. F.; Whitman, J. M.; Granshaw, F. D.; Lillie, R. J.; Hunter, N.; Cronin, V. S.; Resor, P. G.; Olds, S. E.; Miller, M. S.; Walker, R.; Douglas, B. B.

    2013-12-01

    EarthScope is a highly complex technical and scientific endeavor. Making results from EarthScope accessible to the general public, educators, all levels of students, and even geoscience professionals from other disciplines is a very real challenge that must be overcome to realize EarthScope's intended broader impacts of contributing 'to the mitigation of risks from geological hazards ... and the public's understanding of the dynamic Earth.' Here we provided several case examples of how EarthScope science can be effectively communicated and then scaled to reach different or larger audiences. One approach features providing professional development regarding EarthScope and geohazard science to non-university educators who then scale up the impact by communicating to hundreds or even thousands of students and general public members each. EarthScope-funded Teachers on the Leading Edge (TOTLE) ran workshops 2008-2010 for 120 Pacific Northwest teachers and community college educators who subsequently communicated EarthScope and geohazards science to >30,000 students and >1500 other adults. Simultaneously EarthScope's National Office at Oregon State University was running workshops for park interpreters who have since reached >>100,000 park visitors. These earlier projects have served as the foundation for the new Cascadia EarthScope Earthquake and Tsunami Education Program (CEETEP), which is currently running joint workshops for coastal Oregon and Washington teachers, interpreters, and emergency management educators. The other approach featured here is UNAVCO's scaled efforts to make Plate Boundary Observatory (PBO) and other geodetic data more accessible to introductory and majors-level geoscience students and faculty. Initial projects included development of a Teaching Geodesy website on the Science Education Research Center (SERC) and development of teaching modules and activities that use PBO data. Infinitesimal strain analysis using GPS data is a 1-2 week module for majors-level structural geology or geophysics courses that is now published on SERC and UNAVCO websites. Simpler exercises using PBO data have been beta-tested for introductory courses as well. Now UNAVCO has received NSF-funding to develop four more modules (two each for introductory and majors-level) that will feature PBO and other geodetic data. The goal is for these four to serve as the foundation for an ultimate collection of >10 modules.

  3. A Dual-Catalysis Approach to Enantioselective [2+2] Photocycloadditions Using Visible Light

    PubMed Central

    Du, Juana; Skubi, Kazimer L.; Schultz, Danielle M.; Yoon, Tehshik P.

    2015-01-01

    In contrast to the wealth of catalytic systems that are available to control the stereochemistry of thermally promoted cycloadditions, few similarly effective methods exist for the stereocontrol of photochemical cycloadditions. A major unsolved challenge in the design of enantioselective catalytic photocycloaddition reactions has been the difficulty of controlling racemic background reactions that occur by direct photoexcitation of substrates while unbound to catalyst. Here we describe a strategy for eliminating the racemic background reaction in asymmetric [2+2] photocycloadditions of α,β-unsaturated ketones to the corresponding cyclobutanes by employing a dual-catalyst system consisting of a visible light-absorbing transition metal photocatalyst and a stereocontrolling Lewis acid co-catalyst. The independence of these two catalysts enables broader scope, greater stereochemical flexibility, and better efficiency than previously reported methods for enantioselective photochemical cycloadditions. PMID:24763585

  4. Chiral poly-rare earth metal complexes in asymmetric catalysis

    PubMed Central

    Shibasaki, Masakatsu

    2006-01-01

    Asymmetric catalysis is a powerful component of modern synthetic organic chemistry. To further broaden the scope and utility of asymmetric catalysis, new basic concepts for the design of asymmetric catalysts are crucial. Because most chemical reactions involve bond-formation between two substrates or moieties, high enantioselectivity and catalyst activity should be realized if an asymmetric catalyst can activate two reacting substrates simultaneously at defined positions. Thus, we proposed the concept of bifunctional asymmetric catalysis, which led us to the design of new asymmetric catalysts containing two functionalities (e.g. a Lewis acid and a Brønsted base or a Lewis acid and a Lewis base). These catalysts demonstrated broad reaction applicability with excellent substrate generality. Using our catalytic asymmetric reactions as keys steps, efficient total syntheses of pharmaceuticals and their biologically active lead natural products were achieved. PMID:25792774

  5. Investigation of a lithium-halogen exchange flow process for the preparation of boronates by using a cryo-flow reactor.

    PubMed

    Newby, James A; Huck, Lena; Blaylock, D Wayne; Witt, Paul M; Ley, Steven V; Browne, Duncan L

    2014-01-03

    Conducting low-temperature organometallic reactions under continuous flow conditions offers the potential to more accurately control exotherms and thus provide more reproducible and scalable processes. Herein, progress towards this goal with regards to the lithium-halogen exchange/borylation reaction is reported. In addition to improving the scope of substrates available on a research scale, methods to improve reaction profiles and expedite purification of the products are also described. On moving to a continuous system, thermocouple measurements have been used to track exotherms and provide a level of safety for continuous processing of organometallic reagents. The use of an in-line continuous liquid-liquid separation device to circumvent labour intensive downstream off-line processing is also reported. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Experimental Studies of Nuclear Physics Input for γ -Process Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Scholz, Philipp; Heim, Felix; Mayer, Jan; Netterdon, Lars; Zilges, Andreas

    The predictions of reaction rates for the γ process in the scope of the Hauser-Feshbach statistical model crucially depend on nuclear physics input-parameters as optical-model potentials (OMP) or γ -ray strength functions. Precise cross-section measurements at astrophysically relevant energies help to constrain adopted models and, therefore, to reduce the uncertainties in the theoretically predicted reaction rates. During the last years, several cross-sections of charged-particle induced reactions on heavy nuclei have been measured at the University of Cologne. Either by means of the in-beam method at the HORUS γ -ray spectrometer or the activation technique using the Cologne Clover Counting Setup, total and partial cross-sections could be used to further constrain different models for nuclear physics input-parameters. It could be shown that modifications on the α -OMP in the case of the 112Sn(α , γ ) reaction also improve the description of the recently measured cross sections of the 108Cd(α , γ ) and 108Cd(α , n) reaction and other reactions as well. Partial cross-sections of the 92Mo(p, γ ) reaction were used to improve the γ -strength function model in 93Tc in the same way as it was done for the 89Y(p, γ ) reaction.

  7. An Unconventional Redox Cross Claisen Condensation-Aromatization of 4-Hydroxyprolines with Ketones.

    PubMed

    Tang, Mi; Sun, Rengwei; Li, Hao; Yu, Xinhong; Wang, Wei

    2017-08-18

    Reaction of α-amino acids, particularly prolines and their derivatives with carbonyl compounds via decarboxylative redox process, is a viable strategy for synthesis of structurally diverse nitrogen centered heterocyclics. In these processes, the decarboxylation is the essential driving force for the processes. The realization of the redox process without decarboxylation may offer an opportunity to explore new reactions. Herein, we report the discovery of an unprecedented redox Claisen-type condensation aromatization cascade reaction of 4-substituted 4-hydroxyproline and its esters with unreactive ketones. We found that the use of propionic acid as a catalyst and a co-solvent can change the reaction course. The commonly observed redox decarboxylation and aldol condensation reactions are significantly minimized. Moreover, unreactive ketones can effectively participate in the Claisen condensation reaction. The new reactivity enables a redox cyclization via an unconventional Claisen-type condensation reaction of in situ formed enamine intermediates from ketone precursors with 4-substituted 4-hydroxyproline and its esters as electrophilic acylation partners. Under the reaction conditions, the cascade process proceeds highly regio- and stereoselectively to afford highly synthetically and biologically valued cis-2,3-dihydro-1H-pyrrolizin-1-ones with a broad substrate scope in efficient 'one-pot' operation, whereas such structures generally require multiple steps.

  8. Acid–base catalysis over perovskites: a review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Polo-Garzon, Felipe; Wu, Zili

    We present that perovskite catalysts have been extensively studied for reduction–oxidation (redox) reactions; however, their acid–base catalytic properties are still under-explored. This review collects work aiming to study the acid–base catalytic properties of perovskites. Reports regarding combined acid–base/redox catalysis over perovskites lie beyond the scope of the present review. For the characterization of acid–base properties, researchers have studied the interaction of probe molecules with perovskite surfaces by means of multiple techniques that provide information about the density, strength and type of adsorption sites. The top-surface composition of perovskites, which relates to the abundance of the acid–base sites, has been studiedmore » by means of low energy ion scattering (LEIS), and, the less surface sensitive, conventional X-ray photoelectron spectroscopy (XPS). Probe reactions, with the conversion of 2-propanol as the common choice, have also been employed for characterizing the acid–base catalytic properties of perovskites. The complex nature of perovskite surfaces, which explains the still absent fundamental relations between the structure of the catalyst and reaction rates/selectivity, encounters a great challenge due to the surface reconstruction of these materials. In this review, we devote a special section to highlight recent publications that report the impact of surface reconstruction and particle shape on acid–base catalysis over perovskites. In addition, we review promising catalytic performances of perovskite catalysts for other reactions of interest. Challenges in acid–base catalysis over perovskites focus on the development of time-resolved monolayer-sensitive characterization of surfaces under operando conditions and the discernment of combined acid–base/redox reaction mechanisms. Finally, opportunities lay on tuning the acid–base characteristics of perovskites with computation-based catalytic descriptors to achieve desired selectivities and enhanced rates.« less

  9. Acid–base catalysis over perovskites: a review

    DOE PAGES

    Polo-Garzon, Felipe; Wu, Zili

    2018-01-15

    We present that perovskite catalysts have been extensively studied for reduction–oxidation (redox) reactions; however, their acid–base catalytic properties are still under-explored. This review collects work aiming to study the acid–base catalytic properties of perovskites. Reports regarding combined acid–base/redox catalysis over perovskites lie beyond the scope of the present review. For the characterization of acid–base properties, researchers have studied the interaction of probe molecules with perovskite surfaces by means of multiple techniques that provide information about the density, strength and type of adsorption sites. The top-surface composition of perovskites, which relates to the abundance of the acid–base sites, has been studiedmore » by means of low energy ion scattering (LEIS), and, the less surface sensitive, conventional X-ray photoelectron spectroscopy (XPS). Probe reactions, with the conversion of 2-propanol as the common choice, have also been employed for characterizing the acid–base catalytic properties of perovskites. The complex nature of perovskite surfaces, which explains the still absent fundamental relations between the structure of the catalyst and reaction rates/selectivity, encounters a great challenge due to the surface reconstruction of these materials. In this review, we devote a special section to highlight recent publications that report the impact of surface reconstruction and particle shape on acid–base catalysis over perovskites. In addition, we review promising catalytic performances of perovskite catalysts for other reactions of interest. Challenges in acid–base catalysis over perovskites focus on the development of time-resolved monolayer-sensitive characterization of surfaces under operando conditions and the discernment of combined acid–base/redox reaction mechanisms. Finally, opportunities lay on tuning the acid–base characteristics of perovskites with computation-based catalytic descriptors to achieve desired selectivities and enhanced rates.« less

  10. 40 CFR 109.3 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., LOCAL AND REGIONAL OIL REMOVAL CONTINGENCY PLANS § 109.3 Purpose and scope. The guidelines in this part establish minimum criteria for the development and implementation of State, local, and regional contingency..., fish, shellfish, wildlife, and public and private property, shorelines, and beaches. The development...

  11. Adverse Drug Reaction Identification and Extraction in Social Media: A Scoping Review

    PubMed Central

    Bellet, Florelle; Asfari, Hadyl; Souvignet, Julien; Texier, Nathalie; Jaulent, Marie-Christine; Beyens, Marie-Noëlle; Burgun, Anita; Bousquet, Cédric

    2015-01-01

    Background The underreporting of adverse drug reactions (ADRs) through traditional reporting channels is a limitation in the efficiency of the current pharmacovigilance system. Patients’ experiences with drugs that they report on social media represent a new source of data that may have some value in postmarketing safety surveillance. Objective A scoping review was undertaken to explore the breadth of evidence about the use of social media as a new source of knowledge for pharmacovigilance. Methods Daubt et al’s recommendations for scoping reviews were followed. The research questions were as follows: How can social media be used as a data source for postmarketing drug surveillance? What are the available methods for extracting data? What are the different ways to use these data? We queried PubMed, Embase, and Google Scholar to extract relevant articles that were published before June 2014 and with no lower date limit. Two pairs of reviewers independently screened the selected studies and proposed two themes of review: manual ADR identification (theme 1) and automated ADR extraction from social media (theme 2). Descriptive characteristics were collected from the publications to create a database for themes 1 and 2. Results Of the 1032 citations from PubMed and Embase, 11 were relevant to the research question. An additional 13 citations were added after further research on the Internet and in reference lists. Themes 1 and 2 explored 11 and 13 articles, respectively. Ways of approaching the use of social media as a pharmacovigilance data source were identified. Conclusions This scoping review noted multiple methods for identifying target data, extracting them, and evaluating the quality of medical information from social media. It also showed some remaining gaps in the field. Studies related to the identification theme usually failed to accurately assess the completeness, quality, and reliability of the data that were analyzed from social media. Regarding extraction, no study proposed a generic approach to easily adding a new site or data source. Additional studies are required to precisely determine the role of social media in the pharmacovigilance system. PMID:26163365

  12. Adverse Drug Reaction Identification and Extraction in Social Media: A Scoping Review.

    PubMed

    Lardon, Jérémy; Abdellaoui, Redhouane; Bellet, Florelle; Asfari, Hadyl; Souvignet, Julien; Texier, Nathalie; Jaulent, Marie-Christine; Beyens, Marie-Noëlle; Burgun, Anita; Bousquet, Cédric

    2015-07-10

    The underreporting of adverse drug reactions (ADRs) through traditional reporting channels is a limitation in the efficiency of the current pharmacovigilance system. Patients' experiences with drugs that they report on social media represent a new source of data that may have some value in postmarketing safety surveillance. A scoping review was undertaken to explore the breadth of evidence about the use of social media as a new source of knowledge for pharmacovigilance. Daubt et al's recommendations for scoping reviews were followed. The research questions were as follows: How can social media be used as a data source for postmarketing drug surveillance? What are the available methods for extracting data? What are the different ways to use these data? We queried PubMed, Embase, and Google Scholar to extract relevant articles that were published before June 2014 and with no lower date limit. Two pairs of reviewers independently screened the selected studies and proposed two themes of review: manual ADR identification (theme 1) and automated ADR extraction from social media (theme 2). Descriptive characteristics were collected from the publications to create a database for themes 1 and 2. Of the 1032 citations from PubMed and Embase, 11 were relevant to the research question. An additional 13 citations were added after further research on the Internet and in reference lists. Themes 1 and 2 explored 11 and 13 articles, respectively. Ways of approaching the use of social media as a pharmacovigilance data source were identified. This scoping review noted multiple methods for identifying target data, extracting them, and evaluating the quality of medical information from social media. It also showed some remaining gaps in the field. Studies related to the identification theme usually failed to accurately assess the completeness, quality, and reliability of the data that were analyzed from social media. Regarding extraction, no study proposed a generic approach to easily adding a new site or data source. Additional studies are required to precisely determine the role of social media in the pharmacovigilance system.

  13. Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

    PubMed Central

    2015-01-01

    Summary Amino acids, whether natural, semisynthetic or synthetic, are among the most important and useful chiral building blocks available for organic chemical synthesis. In principle, they can function as inexpensive, chiral and densely functionalized starting materials. On the other hand, the use of amino acid starting materials routinely necessitates protective group chemistry, and in reality, large-scale preparations of even the simplest side-chain derivatives of many amino acids often become annoyingly strenuous due to the necessity of employing protecting groups, on one or more of the amino acid functionalities, during the synthetic sequence. However, in the case of hydroxyamino acids such as hydroxyproline, serine, threonine, tyrosine and 3,4-dihydroxyphenylalanine (DOPA), many O-acyl side-chain derivatives are directly accessible via a particularly expedient and scalable method not commonly applied until recently. Direct acylation of unprotected hydroxyamino acids with acyl halides or carboxylic anhydrides under appropriately acidic reaction conditions renders possible chemoselective O-acylation, furnishing the corresponding side-chain esters directly, on multigram-scale, in a single step, and without chromatographic purification. Assuming a certain degree of stability under acidic reaction conditions, the method is also applicable for a number of related compounds, such as various amino alcohols and the thiol-functional amino acid cysteine. While the basic methodology underlying this approach has been known for decades, it has evolved through recent developments connected to amino acid-derived chiral organocatalysts to become a more widely recognized procedure for large-scale preparation of many useful side-chain derivatives of hydroxyamino acids and related compounds. Such derivatives are useful in peptide chemistry and drug development, as amino acid amphiphiles for asymmetric catalysis, and as amino acid acrylic precursors for preparation of catalytically active macromolecular networks in the form of soluble polymers, crosslinked polymer beads or nanoparticulate systems. The objective of the present review is to increase awareness of the existence and convenience of this methodology, assess its competitiveness compared to newer and more elaborate procedures for chemoselective O-acylation reactions, spur its further development, and finally to chronicle the informative, but poorly documented history of its development. PMID:25977719

  14. Work Scope for Developing Standards for Emergency Preparedness and Response: Fiscal Year 2004 Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stenner, Robert D.

    2005-09-28

    Summarizes the fiscal year 2004 work completed on PNNL's Department of Homeland Security Emergency Preparedness and Response Standards Development Project. Also, the report includes key draft standards, in various stages of development and publication, that were associated with various tasks of the fiscal year 2004 scope of the project.

  15. Non-steady state mass action dynamics without rate constants: dynamics of coupled reactions using chemical potentials

    NASA Astrophysics Data System (ADS)

    Cannon, William R.; Baker, Scott E.

    2017-10-01

    Comprehensive and predictive simulation of coupled reaction networks has long been a goal of biology and other fields. Currently, metabolic network models that utilize enzyme mass action kinetics have predictive power but are limited in scope and application by the fact that the determination of enzyme rate constants is laborious and low throughput. We present a statistical thermodynamic formulation of the law of mass action for coupled reactions at both steady states and non-stationary states. The formulation uses chemical potentials instead of rate constants. When used to model deterministic systems, the method corresponds to a rescaling of the time dependent reactions in such a way that steady states can be reached on the same time scale but with significantly fewer computational steps. The relationships between reaction affinities, free energy changes and generalized detailed balance are central to the discussion. The significance for applications in systems biology are discussed as is the concept and assumption of maximum entropy production rate as a biological principle that links thermodynamics to natural selection.

  16. Heavy-Atom Tunneling Calculations in Thirteen Organic Reactions: Tunneling Contributions are Substantial, and Bell's Formula Closely Approximates Multidimensional Tunneling at ≥250 K.

    PubMed

    Doubleday, Charles; Armas, Randy; Walker, Dana; Cosgriff, Christopher V; Greer, Edyta M

    2017-10-09

    Multidimensional tunneling calculations are carried out for 13 reactions, to test the scope of heavy-atom tunneling in organic chemistry, and to check the accuracy of one-dimensional tunneling models. The reactions include pericyclic, cycloaromatization, radical cyclization and ring opening, and S N 2. When compared at the temperatures that give the same effective rate constant of 3×10 -5  s -1 , tunneling accounts for 25-95 % of the rate in 8 of the 13 reactions. Values of transmission coefficients predicted by Bell's formula, κ Bell  , agree well with multidimensional tunneling (canonical variational transition state theory with small curvature tunneling), κ SCT . Mean unsigned deviations of κ Bell vs. κ SCT are 0.08, 0.04, 0.02 at 250, 300 and 400 K. This suggests that κ Bell is a useful first choice for predicting transmission coefficients in heavy-atom tunnelling. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Chlorodifluoromethane-triggered formation of difluoromethylated arenes catalysed by palladium

    NASA Astrophysics Data System (ADS)

    Feng, Zhang; Min, Qiao-Qiao; Fu, Xia-Ping; An, Lun; Zhang, Xingang

    2017-09-01

    Difluoromethylated aromatic compounds are of increasing importance in pharmaceuticals, agrochemicals and materials. Chlorodifluoromethane (ClCF2H), an inexpensive, abundant and widely used industrial raw material, represents the ideal and most straightforward difluoromethylating reagent, but introduction of the difluoromethyl group (CF2H) from ClCF2H into aromatics has not been reported. Here, we describe a direct palladium-catalysed difluoromethylation method for coupling ClCF2H with arylboronic acids and esters to generate difluoromethylated arenes with high efficiency. The reaction exhibits a remarkably broad substrate scope, including heteroarylboronic acids, and was used for difluoromethylation of a range of pharmaceuticals and biologically active compounds. Preliminary mechanistic studies revealed that a palladium difluorocarbene intermediate is involved in the reaction. Although numerous metal-difluorocarbene complexes have been prepared, the catalytic synthesis of difluoromethylated or difluoromethylenated compounds involving metal-difluorocarbene complexes has not received much attention. This new reaction therefore also opens the door to understand metal-difluorocarbene complex catalysed reactions.

  18. Lewis acid-Lewis acid heterobimetallic cooperative catalysis: mechanistic studies and application in enantioselective aza-Michael reaction.

    PubMed

    Yamagiwa, Noriyuki; Qin, Hongbo; Matsunaga, Shigeki; Shibasaki, Masakatsu

    2005-09-28

    The full details of a catalytic asymmetric aza-Michael reaction of methoxylamine promoted by rare earth-alkali metal heterobimetallic complexes are described, demonstrating the effectiveness of Lewis acid-Lewis acid cooperative catalysis. First, enones were used as substrates, and the 1,4-adducts were obtained in good yield (57-98%) and high ee (81-96%). Catalyst loading was successfully reduced to 0.3-3 mol % with enones. To broaden the substrate scope of the reaction to carboxylic acid derivatives, alpha,beta-unsaturated N-acylpyrroles were used as monodentate, carboxylic acid derivatives. With beta-alkyl-substituted N-acylpyrroles, the reaction proceeded smoothly and the products were obtained in high yield and good ee. Transformation of the 1,4-adducts from enones and alpha,beta-unsaturated N-acylpyrroles afforded corresponding chiral aziridines and beta-amino acids. Detailed mechanistic studies, including kinetics, NMR analysis, nonlinear effects, and rare earth metal effects, are also described. The Lewis acid-Lewis acid cooperative mechanism, including the substrate coordination mode, is discussed in detail.

  19. 45 CFR 99.1 - Scope of rules.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Scope of rules. 99.1 Section 99.1 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROCEDURE FOR HEARINGS FOR THE CHILD CARE AND DEVELOPMENT FUND General § 99.1 Scope of rules. (a) The rules of procedure in this section govern the practice...

  20. 7 CFR 1794.24 - Proposals normally requiring an EA with scoping.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 12 2014-01-01 2013-01-01 true Proposals normally requiring an EA with scoping. 1794... Classification of Proposals § 1794.24 Proposals normally requiring an EA with scoping. (a) General. Applications... development of the EA. These types of actions are subject to the requirements of §§ 1794.50 through 1794.54...

  1. 7 CFR 1794.24 - Proposals normally requiring an EA with scoping.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 12 2011-01-01 2011-01-01 false Proposals normally requiring an EA with scoping. 1794... Classification of Proposals § 1794.24 Proposals normally requiring an EA with scoping. (a) General. Applications... development of the EA. These types of actions are subject to the requirements of §§ 1794.50 through 1794.54...

  2. 7 CFR 1794.24 - Proposals normally requiring an EA with scoping.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 12 2012-01-01 2012-01-01 false Proposals normally requiring an EA with scoping. 1794... Classification of Proposals § 1794.24 Proposals normally requiring an EA with scoping. (a) General. Applications... development of the EA. These types of actions are subject to the requirements of §§ 1794.50 through 1794.54...

  3. 7 CFR 1794.24 - Proposals normally requiring an EA with scoping.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 12 2013-01-01 2013-01-01 false Proposals normally requiring an EA with scoping. 1794... Classification of Proposals § 1794.24 Proposals normally requiring an EA with scoping. (a) General. Applications... development of the EA. These types of actions are subject to the requirements of §§ 1794.50 through 1794.54...

  4. 7 CFR 1794.24 - Proposals normally requiring an EA with scoping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Proposals normally requiring an EA with scoping. 1794... Classification of Proposals § 1794.24 Proposals normally requiring an EA with scoping. (a) General. Applications... development of the EA. These types of actions are subject to the requirements of §§ 1794.50 through 1794.54...

  5. Copper/amino acid catalyzed cross-couplings of aryl and vinyl halides with nucleophiles.

    PubMed

    Ma, Dawei; Cai, Qian

    2008-11-18

    Copper-assisted Ullmann-type coupling reactions are valuable transformations for organic synthesis. Researchers have extensively applied these reactions in both academic and industrial settings. However, two important issues, the high reaction temperatures (normally above 150 degrees C) and the stoichiometric amounts of copper necessary, have greatly limited the reaction scope. To solve these problems, we and other groups have recently explored the use of special ligands to promote these coupling reactions. We first showed that the structure of alpha-amino acids can accelerate Cu-assisted Ullmann reactions, leading to the coupling reactions of aryl halides and alpha-amino acids at 80-90 degrees C. In response to these encouraging results, we also discovered that an l-proline ligand facilitated the following transformations: (1) coupling of aryl halides with primary amines, cyclic secondary amines, and N-containing heterocycles at 40-90 degrees C; (2) coupling of aryl halides with sulfinic acid salts at 80-95 degrees C; (3) azidation of aryl halides and vinyl halides with sodium azide at 40-95 degrees C; (4) coupling of aryl halides with activated methylene compounds at 25-50 degrees C. In addition, we found that N,N-dimethylglycine as a ligand facilitated Cu-catalyzed biaryl ether formation at 90 degrees C. Moreover, Sonogashira reactions worked in the absence of palladium and phosphine ligands, forming enamides from vinyl halides and amides at temperatures ranging from ambient temperature up to 80 degrees C. Furthermore, we discovered that an ortho-amide group can accelerate some Ullmann-type reactions. This functional group in combination with other ligand effects allowed for aryl amination or biaryl ether formation at ambient temperature. The coupling between aryl halides and activated methylene compounds even proceeded at -45 degrees C to enantioselectively form a quaternary carbon center. Taking advantage of these results, we developed several novel approaches for the synthesis of pharmaceutically important heterocycles: 1,2-disubstituted benzimidazoles, polysubstituted indoles, N-substituted 1,3-dihydrobenzimidazol-2-ones, and substituted 3-acyl oxindoles. Our results demonstrate that an l-proline or N,N-dimethylglycine ligand can facilitate most typical Ullmann-type reactions, with reactions occurring under relatively mild conditions and using only 2-20 mol % copper catalysts. These conveniently available and inexpensive catalytic systems not only accelerate the reactions but also tolerate many more functional groups. Thus, they should find considerable application in organic synthesis.

  6. Methods for the synthesis of donor-acceptor cyclopropanes

    NASA Astrophysics Data System (ADS)

    Tomilov, Yu V.; Menchikov, L. G.; Novikov, R. A.; Ivanova, O. A.; Trushkov, I. V.

    2018-03-01

    The interest in cyclopropane derivatives is caused by the facts that, first, the three-carbon ring is present in quite a few natural and biologically active compounds and, second, compounds with this ring are convenient building blocks for the synthesis of diverse molecules (acyclic, alicyclic and heterocyclic). The carbon–carbon bonds in cyclopropane are kinetically rather inert; hence, they need to be activated to be involved in reactions. An efficient way of activation is to introduce vicinal electron-donating and electron-withdrawing substituents into the ring; these substrates are usually referred to as donor-acceptor cyclopropanes. This review gives a systematic account of the key methods for the synthesis of donor-acceptor cyclopropanes. The most important among them are reactions of nucleophilic alkenes with diazo compounds and iodonium ylides and approaches based on reactions of electrophilic alkenes with sulfur ylides (the Corey–Chaykovsky reaction). Among other methods used for this purpose, noteworthy are cycloalkylation of CH-acids, addition of α-halocarbonyl compounds to alkenes, cyclization via 1,3-elimination, reactions of alkenes with halocarbenes followed by reduction, the Simmons–Smith reaction and some other. The scope of applicability and prospects of various methods for the synthesis of donor-acceptor cyclopropanes are discussed. The bibliography includes 530 references.

  7. Virtual PCR

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gardner, S N; Clague, D S; Vandersall, J A

    2006-02-23

    The polymerase chain reaction (PCR) stands among the keystone technologies for analysis of biological sequence data. PCR is used to amplify DNA, to generate many copies from as little as a single template. This is essential, for example, in processing forensic DNA samples, pathogen detection in clinical or biothreat surveillance applications, and medical genotyping for diagnosis and treatment of disease. It is used in virtually every laboratory doing molecular, cellular, genetic, ecologic, forensic, or medical research. Despite its ubiquity, we lack the precise predictive capability that would enable detailed optimization of PCR reaction dynamics. In this LDRD, we proposed tomore » develop Virtual PCR (VPCR) software, a computational method to model the kinetic, thermodynamic, and biological processes of PCR reactions. Given a successful completion, these tools will allow us to predict both the sequences and concentrations of all species that are amplified during PCR. The ability to answer the following questions will allow us both to optimize the PCR process and interpret the PCR results: What products are amplified when sequence mixtures are present, containing multiple, closely related targets and multiplexed primers, which may hybridize with sequence mismatches? What are the effects of time, temperature, and DNA concentrations on the concentrations of products? A better understanding of these issues will improve the design and interpretation of PCR reactions. The status of the VPCR project after 1.5 years of funding is consistent with the goals of the overall project which was scoped for 3 years of funding. At half way through the projected timeline of the project we have an early beta version of the VPCR code. We have begun investigating means to improve the robustness of the code, performed preliminary experiments to test the code and begun drafting manuscripts for publication. Although an experimental protocol for testing the code was developed, the preliminary experiments were tainted by contaminated products received from the manufacturer. Much knowledge has been gained in the development of the code thus far, but without final debugging, increasing its robustness and verifying it against experimental results, the papers which we have drafted to share our findings still require the final data necessary for publication. The following sections summarize our final progress on VPCR as it stands after 1.5 years of effort on an ambitious project scoped for a 3 year period. We have additional details of the methods than are provided here, but would like to have legal protection in place before releasing them. The result of this project, a suite of programs that predict PCR products as a function of reaction conditions and sequences, will be used to address outstanding questions in pathogen detection and forensics at LLNL. VPCR should enable scientists to optimize PCR protocols in terms of time, temperature, ion concentration, and primer sequences and concentrations, and to estimate products and error rates in advance of performing experiments. Our proposed capabilities are well ahead of all currently available technologies, which do not model non-equilibrium kinetics, polymerase extension, or predict multiple or undesired PCR products. We are currently seeking DHS funding to complete the project, at which time licensing opportunities will be explored, an updated patent application will be prepared, and a publication will be submitted. A provisional and a full patent application have already been filed (1).« less

  8. 14 CFR § 1274.102 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 5 2014-01-01 2014-01-01 false Scope. § 1274.102 Section § 1274.102 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION COOPERATIVE AGREEMENTS WITH COMMERCIAL... development; (2) Provide technology transfer from the Government to the recipient; or (3) Develop a capability...

  9. Formal Synthesis of (±)-Aplykurodinone-1 through a Hetero-Pauson-Khand Cycloaddition Approach.

    PubMed

    Tao, Cheng; Zhang, Jing; Chen, Xiaoming; Wang, Huifei; Li, Yun; Cheng, Bin; Zhai, Hongbin

    2017-03-03

    The tricyclic intermediate 2 has been synthesized in eight steps from known compound 6 in 20% overall yield. As such, this constitutes a highly efficient formal synthesis of (±)-aplykurodinone-1. This synthesis features a unique, one-pot, intramolecular hetero-Pauson-Khand reaction (h-PKR)/desilylation sequence to expeditiously construct the tricyclic framework, providing valuable insights for expanding the scope and boundaries of h-PKR.

  10. Taming Radical Pairs in Nanocrystalline Ketones: Photochemical Syn-thesis of Compounds with Vicinal Stereogenic All-Carbon Quaternary Centers.

    PubMed

    Dotson, Jordan J; Perez-Estrada, Salvador; Garcia-Garibay, Miguel A

    2018-05-29

    Here we describe the use of crystalline ketones to control the fate of the radical pair intermediates generated in the Norrish type I photodecarbonylation reaction to render it a powerful tool in the challenging synthesis of sterically congested carbon-carbon bonds. This methodology makes the synthetically more accessible hexasusbtituted ketones as ideal synthons for the construction of adjacent, all-carbon substituted, stereogenic quaternary stereocenters. We describe here the structural and thermochemical parameters required of the starting ketone in order to react in the solid state. Finally, the scope and scalability of the reaction and its application in the total synthesis of two natural products is described.

  11. Mechanistic insights into the one-pot synthesis of propargylamines from terminal alkynes and amines in chlorinated solvents catalyzed by gold compounds and nanoparticles.

    PubMed

    Aguilar, David; Contel, Maria; Urriolabeitia, Esteban P

    2010-08-09

    Propargylamines can be obtained from secondary amines and terminal alkynes in chlorinated solvents by a three- and two-component synthesis catalyzed by gold compounds and nanoparticles (Au-NP) under mild conditions. The use of dichloromethane allows for the activation of two C-Cl bonds and a clean transfer of the methylene fragment to the final product. The scope of the reaction as well as the influence of different gold(III) cycloaurated complexes and salts has been investigated. The involvement of gold nanoparticles generated in situ in the process is discussed and a plausible reaction mechanism is proposed on the basis of the data obtained.

  12. Scalable Total Syntheses of N-Linked Tryptamine Dimers by Direct Indole-Aniline Coupling: Psychotrimine and Kapakahines B & F

    PubMed Central

    Newhouse, Timothy; Lewis, Chad A.; Eastman, Kyle J.; Baran, Phil S.

    2010-01-01

    This report details the invention of a method to enable syntheses of psychotrimine, 1, and the kapakahines F and B, 2 & 3, on a gram scale and in a minimum number of steps. Mechanistic inquiries are presented for the key enabling quaternization of indole at the C3 position by electrophilic attack of an activated aniline species. Excellent chemo-, regio-, and diastereoselectivities are observed for reactions with o-iodoaniline, an indole cation equivalent. Additionally, the scope of this reaction is broad with respect to the tryptamine and aniline components. The anti-cancer profiles of psychotrimine, 1, and kapakahines F and B, 2 & 3, have also been evaluated. PMID:20426477

  13. Enantioselective rhodium/ruthenium photoredox catalysis en route to chiral 1,2-aminoalcohols.

    PubMed

    Ma, Jiajia; Harms, Klaus; Meggers, Eric

    2016-08-09

    A rhodium-based chiral Lewis acid catalyst combined with [Ru(bpy)3](PF6)2 as a photoredox sensitizer allows for the visible-light-activated redox coupling of α-silylamines with 2-acyl imidazoles to afford, after desilylation, 1,2-amino-alcohols in yields of 69-88% and with high enantioselectivity (54-99% ee). The reaction is proposed to proceed via an electron exchange between the α-silylamine (electron donor) and the rhodium-chelated 2-acyl imidazole (electron acceptor), followed by a stereocontrolled radical-radical reaction. Substrate scope and control experiments reveal that the trimethylsilyl group plays a crucial role in this reductive umpolung of the carbonyl group.

  14. A review of chemical methods for the selective sulfation and desulfation of polysaccharides.

    PubMed

    Bedini, Emiliano; Laezza, Antonio; Parrilli, Michelangelo; Iadonisi, Alfonso

    2017-10-15

    Sulfated polysaccharides are known to possess several biological activities, with their sulfation pattern acting as a code able to transmit functional information. Due to their high biological and biomedical importance, in the last two decades many reports on the chemical modification of their sulfate distribution as well as on the regioselective insertion of sulfate groups on non-sulfated polysaccharides appeared in literature. In this Review we have for the first time collected these reports together, categorizing them into three different classes: i) regioselective sulfation reactions, ii) regioselective desulfation reactions, iii) regioselective insertion of sulfate groups through multi-step strategies, and discussing their scope and limitations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Simultaneous Interfacial Reactivity and Topography Mapping with Scanning Ion Conductance Microscopy.

    PubMed

    Momotenko, Dmitry; McKelvey, Kim; Kang, Minkyung; Meloni, Gabriel N; Unwin, Patrick R

    2016-03-01

    Scanning ion conductance microscopy (SICM) is a powerful technique for imaging the topography of a wide range of materials and interfaces. In this report, we develop the use and scope of SICM, showing how it can be used for mapping spatial distributions of ionic fluxes due to (electro)chemical reactions occurring at interfaces. The basic idea is that there is a change of ion conductance inside a nanopipet probe when it approaches an active site, where the ionic composition is different to that in bulk solution, and this can be sensed via the current flow in the nanopipet with an applied bias. Careful tuning of the tip potential allows the current response to be sensitive to either topography or activity, if desired. Furthermore, the use of a distance modulation SICM scheme allows reasonably faithful probe positioning using the resulting ac response, irrespective of whether there is a reaction at the interface that changes the local ionic composition. Both strategies (distance modulation or tuned bias) allow simultaneous topography-activity mapping with a single channel probe. The application of SICM reaction imaging is demonstrated on several examples, including voltammetric mapping of electrocatalytic reactions on electrodes and high-speed electrochemical imaging at rates approaching 4 s per image frame. These two distinct approaches provide movies of electrochemical current as a function of potential with hundreds of frames (images) of surface reactivity, to reveal a wealth of spatially resolved information on potential- (and time) dependent electrochemical phenomena. The experimental studies are supported by detailed finite element method modeling that places the technique on a quantitative footing.

  16. You and Your Child: Practical Child Development Information from High/Scope for Parents, with Helpful Support Strategies To Use at Home.

    ERIC Educational Resources Information Center

    Vogel, Nancy

    This document is comprised of 12 issues of a High/Scope newsletter designed to give parents information on child development and to provide suggestions for ways parents can support their preschool child's development at home. Each issue focuses on one aspect of development or learning. The topics for the 12 issues are: (1) dramatic play; (2)…

  17. Auxiliary Propulsion Activities in Support of NASA's Exploration Initiative

    NASA Technical Reports Server (NTRS)

    Best, Philip J.; Unger, Ronald J.; Waits, David A.

    2005-01-01

    The Space Launch Initiative (SLI) procurement mechanism NRA8-30 initiated the Auxiliary Propulsion System/Main Propulsion System (APS/MPS) Project in 2001 to address technology gaps and development risks for non-toxic and cryogenic propellants for auxiliary propulsion applications. These applications include reaction control and orbital maneuvering engines, and storage, pressure control, and transfer technologies associated with on-orbit maintenance of cryogens. The project has successfully evolved over several years in response to changing requirements for re-usable launch vehicle technologies, general launch technology improvements, and, most recently, exploration technologies. Lessons learned based on actual hardware performance have also played a part in the project evolution to focus now on those technologies deemed specifically relevant to the Exploration Initiative. Formal relevance reviews held in the spring of 2004 resulted in authority for continuation of the Auxiliary Propulsion Project through Fiscal Year 2005 (FY05), and provided for a direct reporting path to the Exploration Systems Mission Directorate. The tasks determined to be relevant under the project were: continuation of the development, fabrication, and delivery of three 870 lbf thrust prototype LOX/ethanol reaction control engines; the fabrication, assembly, engine integration and testing of the Auxiliary Propulsion Test Bed at White Sands Test Facility; and the completion of FY04 cryogenic fluid management component and subsystem development tasks (mass gauging, pressure control, and liquid acquisition elements). This paper presents an overview of those tasks, their scope, expectations, and results to-date as carried forward into the Exploration Initiative.

  18. Proposal for an Update of the Definition and Scope of Behavioral Medicine.

    PubMed

    Dekker, Joost; Stauder, Adrienne; Penedo, Frank J

    2017-02-01

    We aim to provide an update of the definition and scope of behavioral medicine in the Charter of ISBM, as the present version was developed more than 25 years ago. We identify issues which need clarification or updating. This leads us to propose an update of the definition and scope of behavioral medicine. Issues in need of clarification or updating include the scope of behavioral medicine (biobehavioral mechanisms, clinical diagnosis and intervention, and prevention and health promotion); research as an essential characteristic of all three areas of behavioral medicine; the application of behavioral medicine; the terminology of behavioral medicine as a multidisciplinary field; and the relationship and distinction between behavioral medicine, mental health, health psychology, and psychosomatic medicine. We propose the following updated definition and scope of behavioral medicine: "Behavioral medicine can be defined as the multidisciplinary field concerned with the development and integration of biomedical and behavioral knowledge relevant to health and disease, and the application of this knowledge to prevention, health promotion, diagnosis, treatment, rehabilitation, and care. The scope of behavioral medicine extends from biobehavioral mechanisms (i.e., the interaction of biomedical processes with psychological, social, societal, cultural, and environmental processes), to clinical diagnosis and intervention, and to public health."

  19. EarthScope National Office (ESNO) Education and Outreach Program and its Broader Impacts: 2015 Update and Handoff to the Next ESNO

    NASA Astrophysics Data System (ADS)

    Semken, S. C.; Robinson, S.; Bohon, W.; Arrowsmith, R.; Garnero, E.; Baumback, D.; Boot, K. E.; Dick, C.

    2015-12-01

    The EarthScope Program (www.earthscope.org), funded by the National Science Foundation, fosters interdisciplinary exploration of the geologic structure and evolution of the North American continent by means of geodesy, seismology, magnetotellurics, in-situ fault-zone sampling, geochronology, and high-resolution topographic measurements. Data and scientific findings from EarthScope are impacting and revolutionizing wide areas of geoscientific research, the understanding and mitigation of geologic hazards, and applications of geoscience to environmental sustainability. The EarthScope Program also produces and disseminates resources and programs for education and outreach (E&O) in the Earth system sciences. The EarthScope National Office (ESNO), operated by Arizona State University from 2011 to 2015, serves all EarthScope stakeholders, including researchers, educators, students, and the general public. ESNO supports and promotes E&O through social media and the web, inSights newsletters and published articles, E&O workshops for informal educators (interpreters), an annual Speaker Series, assistance to K-12 STEM teacher professional development projects led by EarthScope researchers, continuing education for researchers, collaborations with other Earth-science E&O providers, and a biennial National Meeting. Significant activities during the final year of ESNO at ASU included the EarthScope National Meeting in Vermont; Native Science professional-development workshops for Native American teachers in Arizona and Minnesota; a sustained E&O presence online; and preparation for the transition of ESNO from ASU to the next host institution. The EarthScope National Office is supported by the National Science Foundation under grants EAR-1101100 and EAR-1216301. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

  20. Mapping the implementation of evidence-based nutritional management in primary health care settings: a scoping review protocol.

    PubMed

    Oliveira, Nara Leticia Zandonadi de; Agreli, Heloise Lima Fernandes; Matsumoto, Karen Dos Santos; Peduzzi, Marina

    2018-05-01

    The objective of this scoping review is to systematically map and categorize the wide variety of interventions and programs that might be classified under the umbrella term "evidence-based nutritional management in primary healthcare". The development of this scoping review will provide a better understanding of how evidence-based nutritional management has been implemented by healthcare professionals in primary health care settings, especially of barriers and facilitators to implementing evidence-based nutritional management. Therefore, three research questions were chosen to guide the scoping review.

  1. Organocatalytic activation of isocyanides: N-heterocyclic carbene-catalyzed enaminone synthesis from ketones† †Electronic supplementary information (ESI) available: Full data for reaction conditions optimizations, detailed experimental procedures, and full characterization of substrates and products. Crystallographic data for compound 3sa. CCDC 1503347. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc05266e Click here for additional data file. Click here for additional data file.

    PubMed Central

    Kim, Jungwon

    2017-01-01

    The first example of the use of an N-heterocyclic carbene (NHC) as an organocatalyst for the activation of isocyanides was demonstrated. On the basis of previous reports on the interaction between NHCs and isocyanides, we developed a catalytic cycle involving transient imidoyl intermediate. The reaction of ketones with isocyanides produced the corresponding enaminones with high efficiency. Control experiments suggested a novel role for the carbene in the activation of isocyanides, and a proton transfer process was found to be crucial for the generation of two activated species in the catalytic cycle. Various enaminones, some of which are not easily accessible by other methods, were synthesized in excellent yields. This study clearly demonstrates the potential of the nucleophilic activation of isocyanides in the expansion of their reactivity scope. PMID:28451346

  2. Palladium-Catalyzed Allylic C-H Bond Functionalization of Olefins

    NASA Astrophysics Data System (ADS)

    Liu, Guosheng; Wu, Yichen

    Transition metal-mediated carbon-hydrogen bond cleavage and functionalization is a mechanistically interesting and synthetically attractive process. One of the important cases is the removal of a allylic hydrogen from an olefin by a PdII salt to yield a π-allylpalladium complex, followed by nucleophilic attack to efficient produce allylic derivatives. In contrast to the well-known allylic acetoxylation of cyclohexene, the reaction of open-chain olefins is fairly poor until recent several years. Some palladium catalytic systems have been reported to achieve allylic C-H functionalization, including acetoxylation, amination and alkylation of terminal alkenes. In the most of cases, ligand is crucial to the success of the transformation. This review surveys the recent development of palladium-catalyzed allylic C-H functionalziation of alkenes. These results promise a significant increase in the scope of olefin transformation.

  3. High pressure jet flame numerical analysis of CO emissions by means of the flamelet generated manifolds technique

    NASA Astrophysics Data System (ADS)

    Donini, A.; Martin, S. M.; Bastiaans, R. J. M.; van Oijen, J. A.; de Goey, L. P. H.

    2013-10-01

    In the present paper a computational analysis of a high pressure confined premixed turbulent methane/air jet flames is presented. In this scope, chemistry is reduced by the use of the Flamelet Generated Manifold method [1] and the fluid flow is modeled in an LES and RANS context. The reaction evolution is described by the reaction progress variable, the heat loss is described by the enthalpy and the turbulence effect on the reaction is represented by the progress variable variance. The interaction between chemistry and turbulence is considered through a presumed probability density function (PDF) approach. The use of FGM as a combustion model shows that combustion features at gas turbine conditions can be satisfactorily reproduced with a reasonable computational effort. Furthermore, the present analysis indicates that the physical and chemical processes controlling carbon monoxide (CO) emissions can be captured only by means of unsteady simulations.

  4. Chemical reaction mechanisms in solution from brute force computational Arrhenius plots.

    PubMed

    Kazemi, Masoud; Åqvist, Johan

    2015-06-01

    Decomposition of activation free energies of chemical reactions, into enthalpic and entropic components, can provide invaluable signatures of mechanistic pathways both in solution and in enzymes. Owing to the large number of degrees of freedom involved in such condensed-phase reactions, the extensive configurational sampling needed for reliable entropy estimates is still beyond the scope of quantum chemical calculations. Here we show, for the hydrolytic deamination of cytidine and dihydrocytidine in water, how direct computer simulations of the temperature dependence of free energy profiles can be used to extract very accurate thermodynamic activation parameters. The simulations are based on empirical valence bond models, and we demonstrate that the energetics obtained is insensitive to whether these are calibrated by quantum mechanical calculations or experimental data. The thermodynamic activation parameters are in remarkable agreement with experiment results and allow discrimination among alternative mechanisms, as well as rationalization of their different activation enthalpies and entropies.

  5. Chemical reaction mechanisms in solution from brute force computational Arrhenius plots

    PubMed Central

    Kazemi, Masoud; Åqvist, Johan

    2015-01-01

    Decomposition of activation free energies of chemical reactions, into enthalpic and entropic components, can provide invaluable signatures of mechanistic pathways both in solution and in enzymes. Owing to the large number of degrees of freedom involved in such condensed-phase reactions, the extensive configurational sampling needed for reliable entropy estimates is still beyond the scope of quantum chemical calculations. Here we show, for the hydrolytic deamination of cytidine and dihydrocytidine in water, how direct computer simulations of the temperature dependence of free energy profiles can be used to extract very accurate thermodynamic activation parameters. The simulations are based on empirical valence bond models, and we demonstrate that the energetics obtained is insensitive to whether these are calibrated by quantum mechanical calculations or experimental data. The thermodynamic activation parameters are in remarkable agreement with experiment results and allow discrimination among alternative mechanisms, as well as rationalization of their different activation enthalpies and entropies. PMID:26028237

  6. Asymmetric silver-catalysed intermolecular bromotrifluoromethoxylation of alkenes with a new trifluoromethoxylation reagent

    NASA Astrophysics Data System (ADS)

    Guo, Shuo; Cong, Fei; Guo, Rui; Wang, Liang; Tang, Pingping

    2017-06-01

    Fluorinated organic compounds are becoming increasingly important in pharmaceuticals, agrochemicals and materials science. The introduction of trifluoromethoxy groups into new drugs and agrochemicals has attracted much attention due to their strongly electron-withdrawing nature and high lipophilicity. However, synthesis of trifluoromethoxylated organic molecules is difficult owing to the decomposition of trifluoromethoxide anion and β-fluoride elimination from transition-metal-trifluoromethoxide complexes, and no catalytic enantioselective trifluoromethoxylation reaction has been reported until now. Here, we present an example of an asymmetric silver-catalysed intermolecular bromotrifluoromethoxylation of alkenes with trifluoromethyl arylsulfonate (TFMS) as a new trifluoromethoxylation reagent. Compared to other trifluoromethoxylation reagents, TFMS is easily prepared and thermally stable with good reactivity. In addition, this reaction is operationally simple, scalable and proceeds under mild reaction conditions. Furthermore, broad scope and good functional group compatibility has been demonstrated by application of the method to the bromotrifluoromethoxylation of double bonds in natural products and natural product derivatives.

  7. Enantioselective Cyanation of Benzylic C–H Bonds via Copper-Catalyzed Radical Relay

    PubMed Central

    Zhang, Wen; Wang, Fei; McCann, Scott D.; Wang, Dinghai; Chen, Pinhong; Stahl, Shannon; Liu, Guosheng

    2017-01-01

    Direct methods for stereoselective functionalization of C(sp3)–H bonds in complex organic molecules could facilitate much more efficient preparation of therapeutics and agrochemicals. Here, we report a copper-catalyzed radical relay pathway for enantioselective conversion of benzylic C–H bonds into benzylic nitriles. Hydrogen-atom abstraction affords an achiral benzylic radical that undergoes asymmetric C(sp3)–CN bond upon reaction with a chiral copper catalyst. The reactions proceed efficiently at room temperature with the benzylic substrate as limiting reagent, exhibit broad substrate scope with high enantioselectivity (typically 90-99% enantiomeric excess), and afford products that are key precursors to important bioactive molecules. Mechanistic studies provide evidence for diffusible organic radicals and highlight the difference between these reactions and C–H oxidations mediated by enzymes and other catalysts that operate via radical rebound pathways. PMID:27701109

  8. Substrate scope of a dehydrogenase from Sphingomonas species A1 and its potential application in the synthesis of rare sugars and sugar derivatives.

    PubMed

    Beer, Barbara; Pick, André; Döring, Manuel; Lommes, Petra; Sieber, Volker

    2018-07-01

    Rare sugars and sugar derivatives that can be obtained from abundant sugars are of great interest to biochemical and pharmaceutical research. Here, we describe the substrate scope of a short-chain dehydrogenase/reductase from Sphingomonas species A1 (SpsADH) in the oxidation of aldonates and polyols. The resulting products are rare uronic acids and rare sugars respectively. We provide insight into the substrate recognition of SpsADH using kinetic analyses, which show that the configuration of the hydroxyl groups adjacent to the oxidized carbon is crucial for substrate recognition. Furthermore, the specificity is demonstrated by the oxidation of d-sorbitol leading to l-gulose as sole product instead of a mixture of d-glucose and l-gulose. Finally, we applied the enzyme to the synthesis of l-gulose from d-sorbitol in an in vitro system using a NADH oxidase for cofactor recycling. This study shows the usefulness of exploring the substrate scope of enzymes to find new enzymatic reaction pathways from renewable resources to value-added compounds. © 2018 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  9. Orthogonal protection of saccharide polyols through solvent-free one-pot sequences based on regioselective silylations

    PubMed Central

    Traboni, Serena; Bedini, Emiliano

    2016-01-01

    tert-Butyldimethylsilyl (TBDMS) and tert-butyldiphenylsilyl (TBDPS) are alcohol protecting groups widely employed in organic synthesis in view of their compatibility with a wide range of conditions. Their regioselective installation on polyols generally requires lengthy reactions and the use of high boiling solvents. In the first part of this paper we demonstrate that regioselective silylation of sugar polyols can be conducted in short times with the requisite silyl chloride and a very limited excess of pyridine (2–3 equivalents). Under these conditions, that can be regarded as solvent-free conditions in view of the insolubility of the polyol substrates, the reactions are faster than in most examples reported in the literature, and can even be further accelerated with a catalytic amount of tetrabutylammonium bromide (TBAB). The strategy proved also useful for either the selective TBDMS protection of secondary alcohols or the fast per-O-trimethylsilylation of saccharide polyols. In the second part of the paper the scope of the silylation approach was significantly extended with the development of unprecedented “one-pot” and “solvent-free” sequences allowing the regioselective silylation/alkylation (or the reverse sequence) of saccharide polyols in short times. The developed methodologies represent a very useful and experimentally simple tool for the straightforward access to saccharide building-blocks useful in organic synthesis. PMID:28144345

  10. SCOPE: a web server for practical de novo motif discovery.

    PubMed

    Carlson, Jonathan M; Chakravarty, Arijit; DeZiel, Charles E; Gross, Robert H

    2007-07-01

    SCOPE is a novel parameter-free method for the de novo identification of potential regulatory motifs in sets of coordinately regulated genes. The SCOPE algorithm combines the output of three component algorithms, each designed to identify a particular class of motifs. Using an ensemble learning approach, SCOPE identifies the best candidate motifs from its component algorithms. In tests on experimentally determined datasets, SCOPE identified motifs with a significantly higher level of accuracy than a number of other web-based motif finders run with their default parameters. Because SCOPE has no adjustable parameters, the web server has an intuitive interface, requiring only a set of gene names or FASTA sequences and a choice of species. The most significant motifs found by SCOPE are displayed graphically on the main results page with a table containing summary statistics for each motif. Detailed motif information, including the sequence logo, PWM, consensus sequence and specific matching sites can be viewed through a single click on a motif. SCOPE's efficient, parameter-free search strategy has enabled the development of a web server that is readily accessible to the practising biologist while providing results that compare favorably with those of other motif finders. The SCOPE web server is at .

  11. Developing tools to sustain biological diversity.

    Treesearch

    Randy Molina

    2004-01-01

    The Biodiversity Initiative strives to provide innovative solutions to the complex problem of managing forests for biodiversity. Although this initiative is in its beginning stages, an initial scoping meeting has already taken place and planning for the next steps is underway. The initiative is developing plans to conduct extensive scoping efforts in the management,...

  12. Predictions on the Development Dimensions of Provincial Tourism Discipline Based on the Artificial Neural Network BP Model

    ERIC Educational Resources Information Center

    Yang, Yang; Hu, Jun; Lv, Yingchun; Zhang, Mu

    2013-01-01

    As the tourism industry has gradually become the strategic mainstay industry of the national economy, the scope of the tourism discipline has developed rigorously. This paper makes a predictive study on the development of the scope of Guangdong provincial tourism discipline based on the artificial neural network BP model in order to find out how…

  13. Moving Forward with Computational Red Teaming

    DTIC Science & Technology

    2012-07-01

    scoping study of one targeted task within the division. This study would apply the taxonomy developed in this report, in 1 Functional elements are...into the study and development of Computational Red Teaming, following earlier work presented by Gowlett (2011). Gowlett called for the development of...implements the recommendation of Gowlett (2011). It will provide a scoping study of CRT to advance the science in this field. UNCLASSIFIED 1

  14. No Sting Barrier Film to Protect Skin in Adult Patients: Findings From a Scoping Review With Implications for Evidence-Based Practice.

    PubMed

    Micheli, Chiara; Palese, Alvisa; Canzan, Federica; Ambrosi, Elisa

    2017-10-01

    In the industrialized world, approximately 1-1.5% of the population has received treatments for skin lesions. In the 1990s, a polymeric barrier film called the No Sting Barrier Film (NSBF) was developed as an alternative to petrolatum-based ointments and zinc oxide formulas. To date, few studies have explored the effectiveness of NSBF in protecting skin integrity. To map the methods, fields and outcomes used to produce evidence on NSBF effectiveness. A scoping review was performed in 2015. A search strategy for identifying relevant studies was designed and performed. Systematic reviews, meta-analyses, randomized controlled trials, controlled clinical trials, and comparative studies for all types of interventions were included; research conducted in any clinical context was eligible for inclusion. Studies were selected by two reviewers; data extraction and analysis also was performed by two reviewers and disagreements were discussed. Six studies were included. NSBF's potential as a skin protector was investigated with respect to (a) chronic wounds (pressure ulcers or vascular leg ulcers); (b) urinary or fecal incontinence; and (c) post-mastectomy irradiation. The principal clinical outcomes investigated were, respectively: (a) wound healing, wound exudates and erythema control; (b) incidence of incontinence-associated dermatitis and skin reactions; and (c) intensity of pruritus and skin reactions. Pain and comfort were measured in all clinical applications. The main process outcomes investigated were: (a) ease of application, (b) application and removal time, and (c) costs. Zinc oxide and petroleum formulations were the most common comparison interventions in research on chronic ulcers and incontinence; sorbolene cream and topical corticosteroids were the most frequent comparisons in the context of post-mastectomy irradiation. NBSF may be used for peri-wound skin protection in patients with chronic wounds, with urinary or fecal incontinence and for women undergoing post-mastectomy irradiation. However, more robust experimental studies are needed in all clinical fields where NBSF is applied. © 2017 Sigma Theta Tau International.

  15. The Evolution of Chemical High-Throughput Experimentation To Address Challenging Problems in Pharmaceutical Synthesis.

    PubMed

    Krska, Shane W; DiRocco, Daniel A; Dreher, Spencer D; Shevlin, Michael

    2017-12-19

    The structural complexity of pharmaceuticals presents a significant challenge to modern catalysis. Many published methods that work well on simple substrates often fail when attempts are made to apply them to complex drug intermediates. The use of high-throughput experimentation (HTE) techniques offers a means to overcome this fundamental challenge by facilitating the rational exploration of large arrays of catalysts and reaction conditions in a time- and material-efficient manner. Initial forays into the use of HTE in our laboratories for solving chemistry problems centered around screening of chiral precious-metal catalysts for homogeneous asymmetric hydrogenation. The success of these early efforts in developing efficient catalytic steps for late-stage development programs motivated the desire to increase the scope of this approach to encompass other high-value catalytic chemistries. Doing so, however, required significant advances in reactor and workflow design and automation to enable the effective assembly and agitation of arrays of heterogeneous reaction mixtures and retention of volatile solvents under a wide range of temperatures. Associated innovations in high-throughput analytical chemistry techniques greatly increased the efficiency and reliability of these methods. These evolved HTE techniques have been utilized extensively to develop highly innovative catalysis solutions to the most challenging problems in large-scale pharmaceutical synthesis. Starting with Pd- and Cu-catalyzed cross-coupling chemistry, subsequent efforts expanded to other valuable modern synthetic transformations such as chiral phase-transfer catalysis, photoredox catalysis, and C-H functionalization. As our experience and confidence in HTE techniques matured, we envisioned their application beyond problems in process chemistry to address the needs of medicinal chemists. Here the problem of reaction generality is felt most acutely, and HTE approaches should prove broadly enabling. However, the quantities of both time and starting materials available for chemistry troubleshooting in this space generally are severely limited. Adapting to these needs led us to invest in smaller predefined arrays of transformation-specific screening "kits" and push the boundaries of miniaturization in chemistry screening, culminating in the development of "nanoscale" reaction screening carried out in 1536-well plates. Grappling with the problem of generality also inspired the exploration of cheminformatics-driven HTE approaches such as the Chemistry Informer Libraries. These next-generation HTE methods promise to empower chemists to run orders of magnitude more experiments and enable "big data" informatics approaches to reaction design and troubleshooting. With these advances, HTE is poised to revolutionize how chemists across both industry and academia discover new synthetic methods, develop them into tools of broad utility, and apply them to problems of practical significance.

  16. The scale on community care perceptions (scope) for nursing students: A development and psychometric validation study.

    PubMed

    van Iersel, Margriet; de Vos, Rien; Latour, Corine; Kirschner, Paul A; Scholte Op Reimer, Wilma

    2018-05-11

    The aim of this study was to develop a valid instrument to measure student nurses' perceptions of community care (SCOPE). DeVellis' staged model for instrument development and validation was used. Scale construction of SCOPE was based on existing literature. Evaluation of its psychometric properties included exploratory factor analysis and reliability analysis. After pilot-testing, 1062 bachelor nursing students from six institutions in the Netherlands (response rate 81%) took part in the study. SCOPE is a 35-item scale containing: background variables, 11 measuring the affective component, 5 measuring community care perception as a placement, 17 as a future profession, and 2 on the reasons underlying student preference. Principal axis factoring yielded two factors in the affective component scale reflecting 'enjoyment' and 'utility', two in the placement scale reflecting 'learning possibilities' and 'personal satisfaction', and four in the profession scale: 'professional development', 'collaboration', 'caregiving', and 'complexity and workload'. Cronbach's α of the complete scale was 0.892 and of the subscales 0.862, 0.696, and 0.810 respectively. SCOPE is a psychometrically sound instrument for measuring students' perceptions of community care. By determining these perceptions, it becomes possible to positively influence them with targeted curriculum redesign, eventually contributing to decreasing the workforce shortage in community nursing. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Validation in daily clinical situations of Diascope®, a software developed to help healthcare professionals individualize antidiabetic treatment in type 2 diabetes.

    PubMed

    Ampudia-Blasco, Francisco Javier; García-Soidán, Francisco Javier; Rubio Sánchez, Manuela; Phan, Tra-Mi

    2017-03-01

    DiaScope ® is a software to help in individualized prescription of antidiabetic treatment in type 2 diabetes. This study assessed its value and acceptability by different professionals. DiaScope ® was developed based on the ADA-EASD 2012 algorithm and on the recommendation of 12 international diabetes experts using the RAND/UCLA appropriateness method. The current study was performed at a single session. In the first phase, 5 clinical scenarios were evaluated, selecting the most appropriated therapeutic option among 4 possibilities (initial test). In a second phase, the same clinical cases were evaluated with DiaScope ® (final test).Opinion surveys on DiaScope ® were also performed (questionnaire). DiaScope ® changed the selected option 1 or more times in 70.5% of cases. Among 275 evaluated questionnaires, 54.0% strongly agree that DiaScope ® allowed finding easily a similar therapeutic scenario to the corresponding patient, and 52.5 among the obtained answers were clinically plausible. Up to 58.3% will recommend it to a colleague. In particular, primary care physicians with >20 years of professional dedication found with DiaScope ® the most appropriate option for a particular situation against specialists or those with less professional dedication (p<.05). DiaScope ® is an easy to use tool for antidiabetic drug prescription that provides plausible solutions and is especially useful for primary care physicians with more years of professional practice. Copyright © 2017 SEEN. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Interprofessional online learning for primary healthcare: findings from a scoping review

    PubMed Central

    Reeves, Scott; Fletcher, Simon; McLoughlin, Clodagh; Yim, Alastair; Patel, Kunal D

    2017-01-01

    Objectives This article presents the findings from a scoping review which explored the nature of interprofessional online learning in primary healthcare. The review was informed by the following questions: What is the nature of evidence on online postgraduate education for primary healthcare interprofessional teams? What learning approaches and study methods are used in this context? What is the range of reported outcomes for primary healthcare learners, their organisations and the care they deliver to patients/clients? Setting The review explored the global literature on interprofessional online learning in primary healthcare settings. Results The review found that the 23 included studies employed a range of different e-learning methods with contrasting course durations, use of theory, participant mix, approaches to accreditation and assessment of learning. Most of the included studies reported outcomes associated with learner reactions and positive changes in participant attitudes/perceptions and improvement in knowledge/skills as a result of engagement in an e-learning course. In contrast, fewer studies reported changes in participant behaviours, changes in organisational practice and improvements to patients/clients. Conclusions A number of educational, methodological and outcome implications are be offered. E-learning can enhance an education experience, support development, ease time constraints, overcome geographic limitations and can offer greater flexibility. However, it can also contribute to the isolation of learners and its benefits can be negated by technical problems. PMID:28780560

  19. Video messaging: what works to persuade mothers to supervise young children more closely in order to reduce injury risk?

    PubMed

    Morrongiello, Barbara A; Zdzieborski, Daniel; Sandomierski, Megan; Lasenby-Lessard, Jennifer

    2009-03-01

    Recent research reveals that supervision can be a protective factor for childhood injury. Parents who closely supervise young children at home have children who experience fewer injuries. What is not known, however, is what messaging approaches (e.g., injury statistics, graphic images of injured children, personal testimonials by parents) are best to persuade parents to supervise more closely. Using video as the medium, the present focus group study of urban Canadian mothers explored their reactions to different formats and messages in order to: identify best practices to convince mothers that childhood injury prevention is important; determine how best to communicate messages about supervision to mothers; and identify what the nature and scope of these messages should be for motivating and empowering mothers to supervise closely. Results suggest that those who become aware of the scope of childhood injuries are motivated to pay attention to messaging about supervision, that such messages must be delivered with care so that parents do not feel guilty or blamed for acknowledging they could more closely supervise than they already are, that certain messages are not useful for encouraging closer supervision, and that both the content and presentation characteristics (images, accompanying sound) of messages are important determinants of effectiveness for motivating mothers to supervise more closely. Implications for developing interventions that effectively communicate information about child-injury risk and supervision to mothers are discussed.

  20. 28 CFR 79.10 - Scope of subpart.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ACT Eligibility Criteria for Claims Relating to Leukemia § 79.10 Scope of subpart. The regulations in... a designated time period and who later developed leukemia, and $75,000 to individuals who... leukemia. ...

  1. 28 CFR 79.10 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ACT Eligibility Criteria for Claims Relating to Leukemia § 79.10 Scope of subpart. The regulations in... a designated time period and who later developed leukemia, and $75,000 to individuals who... leukemia. ...

  2. 28 CFR 79.10 - Scope of subpart.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ACT Eligibility Criteria for Claims Relating to Leukemia § 79.10 Scope of subpart. The regulations in... a designated time period and who later developed leukemia, and $75,000 to individuals who... leukemia. ...

  3. 28 CFR 79.10 - Scope of subpart.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ACT Eligibility Criteria for Claims Relating to Leukemia § 79.10 Scope of subpart. The regulations in... a designated time period and who later developed leukemia, and $75,000 to individuals who... leukemia. ...

  4. 28 CFR 79.10 - Scope of subpart.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ACT Eligibility Criteria for Claims Relating to Leukemia § 79.10 Scope of subpart. The regulations in... a designated time period and who later developed leukemia, and $75,000 to individuals who... leukemia. ...

  5. Asymmetric hydrogenation of α,β-unsaturated phosphonates with Rh-BisP* and Rh-MiniPHOS catalysts: Scope and mechanism of the reaction

    PubMed Central

    Gridnev, Ilya D.; Yasutake, Masaya; Imamoto, Tsuneo; Beletskaya, Irina P.

    2004-01-01

    Optically active 1,2-bis(alkylmethylphosphino)ethanes and bis(alkylmethylphosphino)methanes are unique diphosphine ligands combining the simple molecular structure and P-stereogenic asymmetric environment. This work shows that these ligands exhibit excellent enantioselectivity in rhodium-catalyzed asymmetric hydrogenation of α,β-unsaturated phosphonic acid derivatives. The enantioselective hydrogenation mechanism elucidated by NMR study is also described. PMID:15024119

  6. α-Carbamoylsulfides as N-Carbamoylimine Precursors in the Visible Light Photoredox-Catalyzed Synthesis of α,α-Disubstituted Amines.

    PubMed

    Lebée, Clément; Languet, Morgan; Allain, Clémence; Masson, Géraldine

    2016-03-18

    A general and practical photoredox-promoted addition of nucleophiles to N-acylimines generated in situ from α-amidosulfides using Ru(bpy)3(PF6)2 as the photocatalyst is reported. The broad scope of the reaction toward various nucleophiles and amidosulfide derivatives was explored. This novel protocol provides a rapid, mild, and efficient access to valuable α,α-disubstituted amines in respectable yields.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pang, Haobo; Gallou, Fabrice; Sohn, Hyuntae

    A remarkable synergistic effect has been uncovered between ppm levels of Pd and Ni embedded within iron nanoparticles that leads to mild and selective catalytic reductions of nitro-containing aromatics and heteroaromatics in water at room temperature. NaBH4 serves as the source of inexpensive hydride. Broad substrate scope is documented, along with several other features including: low catalyst loading, low residual metal in the products, and recycling of the catalyst and reaction medium, highlight the green nature of this new technology.

  8. Improved Schmidt Conversion of Aldehydes to Nitriles Using Azidotrimethylsilane in 1,1,1,3,3,3-Hexafluoro-2-propanol.

    PubMed

    Motiwala, Hashim F; Yin, Qin; Aubé, Jeffrey

    2015-12-29

    The Schmidt reaction of aromatic aldehydes using a substoichiometric amount (40 mol %) of triflic acid is described. Low catalyst loading was enabled by a strong hydrogen-bond-donating solvent hexafluoro-2-propanol (HFIP). This improved protocol tolerates a broad scope of aldehydes with diverse functional groups and the corresponding nitriles were obtained in good to high yields without the need for aqueous work up.

  9. Recent advances and developments on integrating nanotechnology with chemiluminescence assays.

    PubMed

    Tiwari, Ashish; Dhoble, S J

    2018-04-01

    Chemiluminescence (CL) techniques are extensively utilized for detection of analytes due to their high sensitivity, rapidity and selectivity. With the advent of nanotechnology and incorporation of the nanoparticles in the CL system has revolutionized the assays due to their unique optical and mechanical properties. Several CL-based reactions have been developed where these nanoparticle based CL sensors have evolved as excellent prospects for sensing in various analytical applications. This review article addresses the nanoparticles based CL detection system that are recently developed, the mechanisms has been summarized and the role of luminophors have been discussed. This article critically analyzes the optimal conditions for the CL detection along with quantitative assessment of the analytes. We have included the use of semiconductor nanoparticles, metal nanoparticles, graphene based nanostructures, mesoporous nanospheres, layered double hydroxides, clays for CL detection. The scope and application of these nanoscale material based CL system in various branches of science and technology including chemistry, biomedical applications, pharmaceutics, food, environmental and toxicological applications has been critically summarized. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. High/Scope Preschool Key Experiences: Initiative and Social Relations. [with] Curriculum Videotape.

    ERIC Educational Resources Information Center

    Graves, Michelle

    As preschoolers develop the ability to carry out their ideas and play alone and with others, they are developing the foundation for social competence. This booklet and a companion videotape help teachers and parents recognize and support nine High/Scope key experiences in initiative and social relations: (1) making and expressing choices, plans,…

  11. Anxiety and depression, personality traits relevant to tinnitus: A scoping review.

    PubMed

    Durai, Mithila; Searchfield, Grant

    2016-11-01

    Scoping reviews of existing literature were conducted to identify key personality traits relevant to tinnitus, and examine the relationship between affective disorders and tinnitus. The methodological framework of Arksey and O'Malley was followed. Sixty studies were chosen for charting the data, 14 studies examined personality traits exclusively, 31 studies examined affective disorders exclusively, and 15 studies investigated both. The presence of one or more specific personality traits of high neuroticism, low extraversion, high stress reaction, higher alienation, lower social closeness, lower well-being, lower self control, lower psychological acceptance, presence of a type D personality, and externalized locus of control were associated with tinnitus distress. Anxiety and depression were more prevalent among the tinnitus clinical population and at elevated levels. Personality traits have a consistent association with the distress experienced by adult tinnitus help-seekers, and help-seekers are also more likely to experience affective symptoms and/or disorders.

  12. Regioselective, borinic acid-catalyzed monoacylation, sulfonylation and alkylation of diols and carbohydrates: expansion of substrate scope and mechanistic studies.

    PubMed

    Lee, Doris; Williamson, Caitlin L; Chan, Lina; Taylor, Mark S

    2012-05-16

    Synthetic and mechanistic aspects of the diarylborinic acid-catalyzed regioselective monofunctionalization of 1,2- and 1,3-diols are presented. Diarylborinic acid catalysis is shown to be an efficient and general method for monotosylation of pyranoside derivatives bearing three secondary hydroxyl groups (7 examples, 88% average yield). In addition, the scope of the selective acylation, sulfonylation, and alkylation is extended to 1,2- and 1,3-diols not derived from carbohydrates (28 examples); the efficiency, generality, and operational simplicity of this method are competitive with those of state-of-the-art protocols including the broadly applied organotin-catalyzed or -mediated reactions. Mechanistic details of the organoboron-catalyzed processes are explored using competition experiments, kinetics, and catalyst structure-activity relationships. These experiments are consistent with a mechanism in which a tetracoordinate borinate complex reacts with the electrophilic species in the turnover-limiting step of the catalytic cycle.

  13. Catalytic Kinetic Resolution of Saturated N-Heterocycles by Enantioselective Amidation with Chiral Hydroxamic Acids.

    PubMed

    Kreituss, Imants; Bode, Jeffrey W

    2016-12-20

    The preparation of enantioenriched chiral compounds by kinetic resolution dates back to the laboratories of Louis Pasteur in the middle of the 19th century. Unlike asymmetric synthesis, this process can always deliver enantiopure material (ee > 99%) if the reactions are allowed to proceed to sufficient conversion and the selectivity of the process is not unity (s > 1). One of the most appealing and practical variants is acylative kinetic resolution, which affords easily separable reaction products, and several highly efficient enzymatic and small molecule catalysts are available. Unfortunately, this method is applicable to limited substrate classes such as alcohols and primary benzylamines. This Account focuses on our work in catalytic acylative kinetic resolution of saturated N-heterocycles, a class of molecules that has been notoriously difficult to access via asymmetric synthesis. We document the development of hydroxamic acids as suitable catalysts for enantioselective acylation of amines through relay catalysis. Alongside catalyst optimization and reaction development, we present mechanistic studies and theoretical calculation accounting for the origins of selectivity and revealing the concerted nature of many amide-bond forming reactions. Immobilization of the hydroxamic acid to form a polymer supported reagent allows simplification of the experimental setup, improvement in product purification, and extension of the substrate scope. The kinetic resolutions are operationally straight forward: reactions proceed at room temperature and open to air conditions, without generation of difficult-to-remove side products. This was utilized to achieve decagram scale resolution of antimalarial drug mefloquine to prepare more than 50 g of (+)-erythro-meflqouine (er > 99:1) from the racemate. The immobilized quasienantiomeric acyl hydroxamic acid reagents were also exploited for a rare practical implementation of parallel kinetic resolution that affords both enantiomers of the amine products in high enantiopurity. The success of this process relied on identification of two cleavable acyl groups alongside implementation of flow-chemistry techniques to ensure reusability of the resolving agents. The work discussed in this Account has laid foundations for new catalyst design as well as development of desymmetrization and dynamic kinetic resolution processes. In the meantime, as all the requisite reagents are commercially available, we hope that hydroxamic acid promoted acylative kinetic resolution will become a method of choice for preparation of saturated N-heterocycles in enantiopure form.

  14. Generic reactive transport codes as flexible tools to integrate soil organic matter degradation models with water, transport and geochemistry in soils

    NASA Astrophysics Data System (ADS)

    Jacques, Diederik; Gérard, Fréderic; Mayer, Uli; Simunek, Jirka; Leterme, Bertrand

    2016-04-01

    A large number of organic matter degradation, CO2 transport and dissolved organic matter models have been developed during the last decades. However, organic matter degradation models are in many cases strictly hard-coded in terms of organic pools, degradation kinetics and dependency on environmental variables. The scientific input of the model user is typically limited to the adjustment of input parameters. In addition, the coupling with geochemical soil processes including aqueous speciation, pH-dependent sorption and colloid-facilitated transport are not incorporated in many of these models, strongly limiting the scope of their application. Furthermore, the most comprehensive organic matter degradation models are combined with simplified representations of flow and transport processes in the soil system. We illustrate the capability of generic reactive transport codes to overcome these shortcomings. The formulations of reactive transport codes include a physics-based continuum representation of flow and transport processes, while biogeochemical reactions can be described as equilibrium processes constrained by thermodynamic principles and/or kinetic reaction networks. The flexibility of these type of codes allows for straight-forward extension of reaction networks, permits the inclusion of new model components (e.g.: organic matter pools, rate equations, parameter dependency on environmental conditions) and in such a way facilitates an application-tailored implementation of organic matter degradation models and related processes. A numerical benchmark involving two reactive transport codes (HPx and MIN3P) demonstrates how the process-based simulation of transient variably saturated water flow (Richards equation), solute transport (advection-dispersion equation), heat transfer and diffusion in the gas phase can be combined with a flexible implementation of a soil organic matter degradation model. The benchmark includes the production of leachable organic matter and inorganic carbon in the aqueous and gaseous phases, as well as different decomposition functions with first-order, linear dependence or nonlinear dependence on a biomass pool. In addition, we show how processes such as local bioturbation (bio-diffusion) can be included implicitly through a Fickian formulation of transport of soil organic matter. Coupling soil organic matter models with generic and flexible reactive transport codes offers a valuable tool to enhance insights into coupled physico-chemical processes at different scales within the scope of C-biogeochemical cycles, possibly linked with other chemical elements such as plant nutrients and pollutants.

  15. A Roadmap for Recovery/Decontamination Plan for Critical Infrastructure after CBRN Event Involving Drinking Water Utilities: Scoping Study

    DTIC Science & Technology

    2014-05-01

    A Roadmap for Recovery/Decontamination Plan for Critical Infrastructure after CBRN Event Involving Drinking Water Utilities: Scoping Study... Drinking Water Utilities was supported by the Canadian Safety and Security Program (CSSP) which is led by Defence Research and Development Canada’s Centre...after CBRN Event Involving Drinking Water Utilities Scoping Study Prepared by: Vladimir Blinov Konstantin Volchek Emergencies Science and

  16. Sustainable childhood obesity prevention through community engagement (SCOPE) program: evaluation of the implementation phase.

    PubMed

    McIntosh, Bonnie; Daly, Amelia; Mâsse, Louise C; Collet, Jean-Paul; Higgins, Joan Wharf; Naylor, Patti-Jean; Amed, Shazhan

    2015-10-01

    Childhood obesity rates are steadily rising. Sustainable Childhood Obesity Prevention Through Community Engagement (SCOPE) is a community-based participatory action research (PAR) program aimed at preventing childhood obesity. This study aimed to describe community perspectives on, and elicit feedback about, SCOPE's first phase of implementation in two pilot cities in British Columbia, Canada. A case study was implemented using interviews and questionnaires to obtain feedback about SCOPE from two groups: SCOPE coordinators and stakeholders (i.e., individuals and organizations that were a member of the community and engaged with SCOPE coordinators). Participants were recruited via email and (or) by telephone. Coordinators completed a telephone interview. Stakeholders completed a questionnaire and (or) a telephone interview. Thematic analysis was conducted. Participants included 2 coordinators and 15 stakeholders. Participants similarly interpreted SCOPE as a program focused on raising awareness about childhood obesity prevention, while engaging multiple community sectors. Overall, participants valued the program's role in facilitating networking and partnership development, providing evidence-based resources, technical expertise, and contributing funding. Participants felt that SCOPE is sustainable. However, participants felt that barriers to achieving healthy weights among children included those related to the built environment, and social, behavioral, and economic obstacles. Perspectives on factors that facilitated and acted as barriers to SCOPE's first phase of implementation were obtained from the SCOPE communities and may be used to enhance the sustainability of SCOPE and its applicability to other BC communities.

  17. Ejection of Coulomb Crystals from a Linear Paul Ion Trap for Ion-Molecule Reaction Studies.

    PubMed

    Meyer, K A E; Pollum, L L; Petralia, L S; Tauschinsky, A; Rennick, C J; Softley, T P; Heazlewood, B R

    2015-12-17

    Coulomb crystals are being increasingly employed as a highly localized source of cold ions for the study of ion-molecule chemical reactions. To extend the scope of reactions that can be studied in Coulomb crystals-from simple reactions involving laser-cooled atomic ions, to more complex systems where molecular reactants give rise to multiple product channels-sensitive product detection methodologies are required. The use of a digital ion trap (DIT) and a new damped cosine trap (DCT) are described, which facilitate the ejection of Coulomb-crystallized ions onto an external detector for the recording of time-of-flight (TOF) mass spectra. This enables the examination of reaction dynamics and kinetics between Coulomb-crystallized ions and neutral molecules: ionic products are typically cotrapped, thus ejecting the crystal onto an external detector reveals the masses, identities, and quantities of all ionic species at a selected point in the reaction. Two reaction systems are examined: the reaction of Ca(+) with deuterated isotopologues of water, and the charge exchange between cotrapped Xe(+) with deuterated isotopologues of ammonia. These reactions are examples of two distinct types of experiment, the first involving direct reaction of the laser-cooled ions, and the second involving reaction of sympathetically-cooled heavy ions to form a mixture of light product ions. Extensive simulations are conducted to interpret experimental results and calculate optimal operating parameters, facilitating a comparison between the DIT and DCT approaches. The simulations also demonstrate a correlation between crystal shape and image shape on the detector, suggesting a possible means for determining crystal geometry for nonfluorescing ions.

  18. Reaction of Donor-Acceptor Cyclobutanes with Indoles: A General Protocol for the Formal Total Synthesis of (±)-Strychnine and the Total Synthesis of (±)-Akuammicine.

    PubMed

    Feng, Liang-Wen; Ren, Hai; Xiong, Hu; Wang, Pan; Wang, Lijia; Tang, Yong

    2017-03-06

    A ligand-promoted catalytic [4+2] annulation reaction using indole derivatives and donor-acceptor (D-A) cyclobutanes is reported, thus providing an efficient and atom-economical access to versatile cyclohexa-fused indolines with excellent levels of diastereoselectivity and a broad substrate scope. In the presence of a chiral SaBOX ligand, excellent enantioselectivity was realized with up to 94 % ee. This novel synthetic method is applied as a general protocol for the total synthesis of (±)-akuammicine and the formal total synthesis of (±)-strychnine from the same common-core scaffold. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Recent advances in heterobimetallic catalysis across a "transition metal-tin" motif.

    PubMed

    Das, Debjit; Mohapatra, Swapna Sarita; Roy, Sujit

    2015-06-07

    Heterobimetallic catalysts, bearing a metal-metal bond between a transition metal (TM) and a tin atom, are very promising due to their ability in mediating a wide variety of organic transformations. Indeed the utilization of such catalysts is a challenging and evolving area in the field of homogeneous catalysis. Catalysis across a 'TM-Sn' motif is an emerging area in the broader domain of multimetallic catalysis. The present review apprises the chemists' community of the past, present and future scope of this versatile catalytic motif. The TM-Sn catalyzed reactions presented include, among others, Friedel-Crafts alkylation, carbonylation, polymerization, cyclization, olefin metathesis, Heck coupling, hydroarylation Michael addition and tandem coupling. The mechanistic aspects of the reactions have been highlighted as well.

  20. A new synthetic approach to functionalize pyrimido[4,5-b]quinoline-2,4(1H,3H)-diones via a three-component one-pot reaction.

    PubMed

    Aknin, Karen; Desbène-Finck, Stéphanie; Helissey, Philippe; Giorgi-Renault, Sylviane

    2010-02-01

    Functionalized pyrimido[4,5-b]quinoline-2,4 (1H,3H)-diones were synthesized by a three-component one-pot reaction involving barbituric acid, aldehydes, and anilines. The use of commercially available anilines allowed the facile syntheses of pyrimido[4,5-b]quinolinediones substituted in all the positions on the benzene ring with electron donor or electron withdrawing groups. This straightforward method circumvents the preparation of unstable substituted 2-aminobenzaldehydes that limits the scope of previously described syntheses. Furthermore, access to the 5-substituted derivatives is now also possible starting from aliphatic or aromatic aldehydes. Our strategy and methodology offer significant and practical improvements over other methodologies.

  1. On initial steps of chemical prebiotic evolution: Triggering autocatalytic reaction of oligomerization

    NASA Astrophysics Data System (ADS)

    Bartsev, S. I.; Mezhevikin, V. V.

    2008-12-01

    Searching for extraterrestrial life attracts more and more attention. However this searching hardly can be effective without sufficiently universal concept of life origin, which incidentally tackles a problem of origin of life on the Earth. A concept of initial stages of life origin is stated in the paper. The concept eliminates key difficulties in the problem of life origin, and allows experimental verification of it. According to the concept the predecessor of living beings has to be sufficiently simple to provide non-zero probability of self-assembling during short (in geological or cosmic scale) time. In addition the predecessor has to be capable of autocatalysis, and further complication (evolution). A possible scenario of initial stage of life origin, which can be realized both on other planets, and inside experimental facility is considered. In the scope of the scenario a theoretical model of multivariate oligomeric autocatalyst is presented. Results of computer simulation of two versions of oligomeric autocatalytic reactions are presented. It is shown that the contribution of monomer activation reaction is essential, and in some cases autocatalysis in polymerizing reaction can be achieved without catalyzing proper monomer binding reaction.

  2. Consistent Estimation of Gibbs Energy Using Component Contributions

    PubMed Central

    Milo, Ron; Fleming, Ronan M. T.

    2013-01-01

    Standard Gibbs energies of reactions are increasingly being used in metabolic modeling for applying thermodynamic constraints on reaction rates, metabolite concentrations and kinetic parameters. The increasing scope and diversity of metabolic models has led scientists to look for genome-scale solutions that can estimate the standard Gibbs energy of all the reactions in metabolism. Group contribution methods greatly increase coverage, albeit at the price of decreased precision. We present here a way to combine the estimations of group contribution with the more accurate reactant contributions by decomposing each reaction into two parts and applying one of the methods on each of them. This method gives priority to the reactant contributions over group contributions while guaranteeing that all estimations will be consistent, i.e. will not violate the first law of thermodynamics. We show that there is a significant increase in the accuracy of our estimations compared to standard group contribution. Specifically, our cross-validation results show an 80% reduction in the median absolute residual for reactions that can be derived by reactant contributions only. We provide the full framework and source code for deriving estimates of standard reaction Gibbs energy, as well as confidence intervals, and believe this will facilitate the wide use of thermodynamic data for a better understanding of metabolism. PMID:23874165

  3. Pyrrolidine and Piperidine Formation Via Copper(II) Carboxylate Promoted Intramolecular Carboamination of Unactivated Olefins: Diastereoselectivity and Mechanism

    PubMed Central

    Sherman, Eric S.; Fuller, Peter H.; Kasi, Dhanalakshmi; Chemler, Sherry R.

    2008-01-01

    An expanded substrate scope and in depth analysis of the reaction mechanism of the copper(II) carboxylate promoted intramolecular carboamination of unactivated alkenes is described. This method provides access to N-functionalized pyrrolidines and piperidines. Both aromatic and aliphatic γ- and δ-alkenyl N-arylsulfonamides undergo the oxidative cyclization reaction efficiently. N-Benzoyl-2-allylaniline also underwent the oxidative cyclization. The terminal olefin substrates examined were more reactive than those with internal olefins, and the latter terminated in elimination rather than carbon-carbon bond formation. The efficiency of the reaction was enhanced by the use of more organic soluble copper(II) carboxylate salts, copper(II) neodecanoate in particular. The reaction times were reduced by the use of microwave heating. High levels of diastereoselectivity were observed in the synthesis of 2,5-disubstituted pyrrolidines, wherein the cis substitution pattern predominates. The mechanism of the reaction is discussed in the context of the observed reactivity and in comparison to analogous reactions promoted by other reagents and conditions. Our evidence supports a mechanism wherein the N-C bond is formed via intramolecular syn aminocupration and the C-C bond is formed via intramolecular addition of a primary carbon radical to an aromatic ring. PMID:17428100

  4. Heterocyclic alpha-alkylidene cyclopentenones obtained via a Pauson-Khand reaction of amino acid derived allenynes. A scope and limitation study directed toward the preparation of a tricyclic pyrrole library.

    PubMed

    Brummond, Kay M; Curran, Dennis P; Mitasev, Branko; Fischer, Stefan

    2005-03-04

    The synthesis of a novel class of tricyclic pyrroles has been accomplished by using a Pauson-Khand/Stetter/Paal-Knorr reaction sequence. Full details of the Pauson-Khand reaction of amino acid tethered allenynes 4a-e and 9a-d are disclosed. The study of this reaction led to the discovery of an unprecedented substituent effect on the diastereoselectivity of the Mo(CO)6 mediated allenic Pauson-Khand reaction. It was found that amino acid tethered allenynes with aromatic side chains afford alpha-alkylidene cyclopentenones with the opposite diastereoselectivity compared to those with aliphatic side chains. This effect has been attributed to complexation of the metal mediator to the aromatic ring in the substrate. Furthermore, an isomerization of one of the diastereomers of the alpha-alkylidene cyclopentenones was encountered, leading to eventual decomposition. The stable diastereomers were found to react well in the Stetter reaction leading to 1,4-diketones that were converted to pyrroles. The observation that the first generation of 2-alkyl-substituted pyrroles was unstable led to a second generation of 2-carboxamide pyrroles with sufficient stability for biological tests which are in progress.

  5. Prioritizing Health: A Systematic Approach to Scoping Determinants in Health Impact Assessment.

    PubMed

    McCallum, Lindsay C; Ollson, Christopher A; Stefanovic, Ingrid L

    2016-01-01

    The determinants of health are those factors that have the potential to affect health, either positively or negatively, and include a range of personal, social, economic, and environmental factors. In the practice of health impact assessment (HIA), the stage at which the determinants of health are considered for inclusion is during the scoping step. The scoping step is intended to identify how the HIA will be carried out and to set the boundaries (e.g., temporal and geographical) for the assessment. There are several factors that can help to inform the scoping process, many of which are considered in existing HIA tools and guidance; however, a systematic method of prioritizing determinants was found to be lacking. In order to analyze existing HIA scoping tools that are available, a systematic literature review was conducted, including both primary and gray literature. A total of 10 HIA scoping tools met the inclusion/exclusion criteria and were carried forward for comparative analysis. The analysis focused on minimum elements and practice standards of HIA scoping that have been established in the field. The analysis determined that existing approaches lack a clear, systematic method of prioritization of health determinants for inclusion in HIA. This finding led to the development of a Systematic HIA Scoping tool that addressed this gap. The decision matrix tool uses factors, such as impact, public concern, and data availability, to prioritize health determinants. Additionally, the tool allows for identification of data gaps and provides a transparent method for budget allocation and assessment planning. In order to increase efficiency and improve utility, the tool was programed into Microsoft Excel. Future work in the area of HIA methodology development is vital to the ongoing success of the practice and utilization of HIA as a reliable decision-making tool.

  6. SCOPe: Manual Curation and Artifact Removal in the Structural Classification of Proteins - extended Database.

    PubMed

    Chandonia, John-Marc; Fox, Naomi K; Brenner, Steven E

    2017-02-03

    SCOPe (Structural Classification of Proteins-extended, http://scop.berkeley.edu) is a database of relationships between protein structures that extends the Structural Classification of Proteins (SCOP) database. SCOP is an expert-curated ordering of domains from the majority of proteins of known structure in a hierarchy according to structural and evolutionary relationships. SCOPe classifies the majority of protein structures released since SCOP development concluded in 2009, using a combination of manual curation and highly precise automated tools, aiming to have the same accuracy as fully hand-curated SCOP releases. SCOPe also incorporates and updates the ASTRAL compendium, which provides several databases and tools to aid in the analysis of the sequences and structures of proteins classified in SCOPe. SCOPe continues high-quality manual classification of new superfamilies, a key feature of SCOP. Artifacts such as expression tags are now separated into their own class, in order to distinguish them from the homology-based annotations in the remainder of the SCOPe hierarchy. SCOPe 2.06 contains 77,439 Protein Data Bank entries, double the 38,221 structures classified in SCOP. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  7. EarthScope Education and Outreach: Accomplishments and Emerging Opportunities

    NASA Astrophysics Data System (ADS)

    Robinson, S.; Ellins, K. K.; Semken, S. C.; Arrowsmith, R.

    2014-12-01

    EarthScope's Education and Outreach (E&O) program aims to increase public awareness of Earth science and enhance geoscience education at the K-12 and college level. The program is distinctive among major geoscience programs in two ways. First, planning for education and public engagement occurred in tandem with planning for the science mission. Second, the NSF EarthScope program includes funding support for education and outreach. In this presentation, we highlight key examples of the program's accomplishments and identify emerging E&O opportunities. E&O efforts have been collaboratively led by the EarthScope National Office (ESNO), IRIS, UNAVCO, the EarthScope Education and Outreach Subcommittee (EEOSC) and PI-driven EarthScope projects. Efforts by the EEOSC, guided by an EarthScope Education and Outreach Implementation Plan that is periodically updated, focus EarthScope E&O. EarthScope demonstrated early success in engaging undergraduate students (and teachers) in its mission through their involvement in siting USArray across the contiguous U.S. Funded E&O programs such as TOTLE, Illinois EarthScope, CEETEP (for K-12), InTeGrate and GETSI (for undergraduates) foster use of freely available EarthScope data and research findings. The Next Generation Science Standards, which stress science and engineering practices, offer an opportunity for alignment with existing EarthScope K-12 educational resources, and the EEOSC recommends focusing efforts on this task. The EEOSC recognizes the rapidly growing use of mobile smart devices by the public and in formal classrooms, which bring new opportunities to connect with the public and students. This will capitalize on EarthScope's already prominent social media presence, an effort that developed to accomplish one of the primary goals of the EarthScope E&O Implementation Plan to "Create a high-profile public identity for EarthScope" and to "Promote science literacy and understanding of EarthScope among all audiences through informal education venues" Leveraging ESNO, IRIS, and UNAVCO resources has exceeded the capabilities of any single entity, thereby amplifying the impact of EarthScope's education and outreach effort.

  8. Lewis Acid Induced Toggle from Ir(II) to Ir(IV) Pathways in Photocatalytic Reactions: Synthesis of Thiomorpholines and Thiazepanes from Aldehydes and SLAP Reagents

    PubMed Central

    2016-01-01

    Redox neutral photocatalytic transformations often require careful pairing of the substrates and photoredox catalysts in order to achieve a catalytic cycle. This can limit the range of viable transformations, as we recently observed in attempting to extend the scope of the photocatalytic synthesis of N-heterocycles using silicon amine protocol (SLAP) reagents to include starting materials that require higher oxidation potentials. We now report that the inclusion of Lewis acids in photocatalytic reactions of organosilanes allows access to a distinct reaction pathway featuring an Ir(III)*/Ir(IV) couple instead of the previously employed Ir(III)*/Ir(II) pathway, enabling the transformation of aromatic and aliphatic aldehydes to thiomorpholines and thiazepanes. The role of the Lewis acid in accepting an electron—either directly or via coordination to an imine—can be extended to other classes of photocatalysts and transformations, including oxidative cyclizations. The combination of light induced reactions and Lewis acids therefore promises access to new pathways and transformations that are not viable using the photocatalysts alone. PMID:28149955

  9. Developing Skills in Counselling and Psychotherapy: A Scoping Review of Interpersonal Process Recall and Reflecting Team Methods in Initial Therapist Training

    ERIC Educational Resources Information Center

    Meekums, Bonnie; Macaskie, Jane; Kapur, Tricia

    2016-01-01

    The authors conducted a scoping review of the peer-reviewed literature associated with Interpersonal Process Recall (IPR) and Reflecting Team (RT) methods in order to find evidence for their use within skills development in therapist trainings. Inclusion criteria were: empirical research, reviews of empirical research, and responses to these; RT…

  10. Tender Care and Early Learning: Supporting Infants and Toddlers in Child Care Settings.

    ERIC Educational Resources Information Center

    Post, Jacalyn; Hohmann, Mary

    High/Scope has a long history of curriculum development, training, and research in the area of infant and toddler development. This book explores how the approach can be implemented with infants and toddlers in group care settings. Following an introduction outlining the history of and principles guiding the High/Scope Infant and Toddler Approach,…

  11. Versatile Tandem Ring-Opening/Ring-Closing Metathesis Polymerization: Strategies for Successful Polymerization of Challenging Monomers and Their Mechanistic Studies.

    PubMed

    Park, Hyeon; Kang, Eun-Hye; Müller, Laura; Choi, Tae-Lim

    2016-02-24

    Tandem ring-opening/ring-closing metathesis (RO/RCM) results in extremely fast living polymerization; however, according to previous reports, only monomers containing certain combinations of cycloalkenes, terminal alkynes, and nitrogen linkers successfully underwent tandem polymerization. After examining the polymerization pathways, we proposed that the relatively slow intramolecular cyclization might lead to competing side reactions such as intermolecular cross metathesis reactions to form inactive propagating species. Thus, we developed two strategies to enhance tandem polymerization efficiency. First, we modified monomer structures to accelerate tandem RO/RCM cyclization by enhancing the Thorpe-Ingold effect. This strategy increased the polymerization rate and suppressed the chain transfer reaction to achieve controlled polymerization, even for challenging syntheses of dendronized polymers. Alternatively, reducing the reaction concentration facilitated tandem polymerization, suggesting that the slow tandem RO/RCM cyclization step was the main reason for the previous failure. To broaden the monomer scope, we used monomers containing internal alkynes and observed that two different polymer units with different ring sizes were produced as a result of nonselective α-addition and β-addition on the internal alkynes. Thorough experiments with various monomers with internal alkynes suggested that steric and electronic effects of the alkyne substituents influenced alkyne addition selectivity and the polymerization reactivity. Further polymerization kinetics studies revealed that the rate-determining step of monomers containing certain internal alkynes was the six-membered cyclization step via β-addition, whereas that for other monomers was the conventional intermolecular propagation step, as observed in other chain-growth polymerizations. This conclusion agrees well with all those polymerization results and thus validates our strategies.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farmer, M. T.

    The overall objective of the current work is to carry out a scoping analysis to determine the impact of ATF on late phase accident progression; in particular, the molten core-concrete interaction portion of the sequence that occurs after the core debris fails the reactor vessel and relocates into containment. This additional study augments previous work by including kinetic effects that govern chemical reaction rates during core-concrete interaction. The specific ATF considered as part of this study is SiC-clad UO 2.

  13. Economics of Pharmacogenetic-Guided Treatments: Underwhelming or Overstated?

    PubMed

    Hughes, Dyfrig A

    2018-05-01

    Economic evaluations have dispelled a perception that precision medicine, achieved through pharmacogenetic testing, reduces healthcare costs. For many tests aimed at preventing adverse drug reactions, cost-effectiveness analyses predict modest improvements in health benefits and increases in total costs. While there are many uncertainties in estimating the value of testing, factors that influence cost-effectiveness include the rarity of the outcome, the effectiveness of alternative treatments, and the scope and perspective of analysis. © 2018 ASCPT.

  14. Implementing advanced nurse practitioner roles in acute care: an evaluation of organizational change.

    PubMed

    Cummings, Greta G; Fraser, Kim; Tarlier, Denise S

    2003-03-01

    Medical shortages are seen as the driving force behind the recent implementation of the advanced nurse practitioner (ANP) role in some Canadian hospitals. The authors analyzed the implementation of the ANP role in one tertiary care teaching hospital from the organizational change perspective. Despite successful implementation, issues of role definition, scope of practice boundaries, and staff reactions remain unresolved. Recommendations are discussed for implementing ANP roles in other acute care facilities.

  15. α-Amination of aldehydes catalyzed by in situ generated hypoiodite.

    PubMed

    Tian, Jie-Sheng; Ng, Kang Wai Jeffrey; Wong, Jiun-Ru; Loh, Teck-Peng

    2012-09-03

    The metal-free amination of different aldehydes is catalyzed by hypoiodite, which is generated by employing commercially available sodium percarbonate as the co-oxidant. This approach has several advantages: it is a metal-free oxidation that works under mild reaction conditions; furthermore, it has a wide substrate scope and does not give toxic by-products from the co-oxidant that is used. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Scope of nanotechnology in modern textiles

    USDA-ARS?s Scientific Manuscript database

    This review article demonstrates the scope and applications of nanotechnology towards modification and development of advanced textile fibers, yarns and fabrics and their processing techniques. Basically, it summarizes the recent advances made in nanotechnology and its applications to cotton textil...

  17. 5 CFR 293.101 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....101 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Basic Policies on Maintenance of Personnel Records § 293.101 Purpose and scope. (a) This subpart sets forth basic policies governing the creation, development, maintenance, processing, use...

  18. 16 CFR 1031.16 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL COMMISSION PARTICIPATION AND COMMISSION... and scope. (a) This subpart sets forth the Consumer Product Safety Commission's criteria and... development bodies. (b) The Commission realizes there are advantages and benefits afforded by greater public...

  19. Pre-contract project scoping processes : synthesis of practices.

    DOT National Transportation Integrated Search

    2016-02-01

    Scoping is the process of developing a projects objectives, need, preliminary cost estimate, and preliminary schedule based on a : recognized need that the project is intended to address. This study (INDOT/JTRP SPR-3944) was launched by the Indian...

  20. Analysis of CRRES PHA Data for Low-Energy-Deposition Events

    NASA Technical Reports Server (NTRS)

    McNulty, P. J.; Hardage, Donna

    2004-01-01

    This effort analyzed the low-energy deposition Pulse Height Analyzer (PHA) data from the Combined Release and Radiation Effects Satellite (CRRES). The high-energy deposition data had been previously analyzed and shown to be in agreement with spallation reactions predicted by the Clemson University Proton Interactions in Devices (CUPID) simulation model and existing environmental and orbit positioning models (AP-8 with USAF B-L coordinates). The scope of this project was to develop and improve the CUPID model by increasing its range to lower incident particle energies, and to expand the modeling to include contributions from elastic interactions. Before making changes, it was necessary to identify experimental data suitable for benchmarking the codes; then, the models to the CRRES PHA data could be applied. It was also planned to test the model against available low-energy proton or neutron SEU data obtained with mono-energetic beams.

  1. Dynamic urea bond for the design of reversible and self-healing polymers

    NASA Astrophysics Data System (ADS)

    Ying, Hanze; Zhang, Yanfeng; Cheng, Jianjun

    2014-02-01

    Polymers bearing dynamic covalent bonds may exhibit dynamic properties, such as self-healing, shape memory and environmental adaptation. However, most dynamic covalent chemistries developed so far require either catalyst or change of environmental conditions to facilitate bond reversion and dynamic property change in bulk materials. Here we report the rational design of hindered urea bonds (urea with bulky substituent attached to its nitrogen) and the use of them to make polyureas and poly(urethane-urea)s capable of catalyst-free dynamic property change and autonomous repairing at low temperature. Given the simplicity of the hindered urea bond chemistry (reaction of a bulky amine with an isocyanate), incorporation of the catalyst-free dynamic covalent urea bonds to conventional polyurea or urea-containing polymers that typically have stable bulk properties may further broaden the scope of applications of these widely used materials.

  2. Dynamic urea bond for the design of reversible and self-healing polymers

    PubMed Central

    Ying, Hanze; Zhang, Yanfeng; Cheng, Jianjun

    2014-01-01

    Polymers bearing dynamic covalent bonds may exhibit dynamic properties, such as self-healing, shape memory and environmental adaptation. However, most dynamic covalent chemistries developed so far require either catalyst or change of environmental conditions to facilitate bond reversion and dynamic property change in bulk materials. Here we report the rational design of hindered urea bonds (urea with bulky substituent attached to its nitrogen) and the use of them to make polyureas and poly(urethane-ureas) capable of catalyst-free dynamic property change and autonomous repairing at low temperature. Given the simplicity of the hindered urea bond chemistry (reaction of a bulky amine with an isocyanate), incorporation of the catalyst-free dynamic covalent urea bonds to conventional polyurea or urea-containing polymers that typically have stable bulk properties may further broaden the scope of applications of these widely used materials. PMID:24492620

  3. Stable dimeric magnesium(I) compounds: from chemical landmarks to versatile reagents.

    PubMed

    Stasch, Andreas; Jones, Cameron

    2011-06-07

    The chemistry of the s-block metals is dominated by the +1 oxidation state for the Alkali metals (group 1) and the +2 oxidation state for the Alkaline Earth metals (group 2). In recent years, a series of stable dimeric magnesium(I) compounds has been prepared and their chemistry has started to develop. These complexes feature "deformable" Mg-Mg single bonds and are stabilised by sterically demanding and chelating anionic N-ligands that prevent their disproportionation. They have rapidly proven useful in organic and organometallic/inorganic reduction reactions as hydrocarbon soluble, stoichiometric, selective and safe reducing agents. The scope of this perspective focuses on stable molecular compounds of the general type LMgMgL and describes their synthesis, structures, theoretical and spectroscopic studies as well as their further chemistry. Also, comparisons are drawn with related complexes including magnesium(II) hydrides and dimeric zinc(I) compounds.

  4. Selective Oxidation of Lignin Model Compounds.

    PubMed

    Gao, Ruili; Li, Yanding; Kim, Hoon; Mobley, Justin K; Ralph, John

    2018-05-02

    Lignin, the planet's most abundant renewable source of aromatic compounds, is difficult to degrade efficiently to welldefined aromatics. We developed a microwave-assisted catalytic Swern oxidation system using an easily prepared catalyst, MoO 2 Cl 2 (DMSO) 2 , and DMSO as the solvent and oxidant. It demonstrated high efficiency in transforming lignin model compounds containing the units and functional groups found in native lignins. The aromatic ring substituents strongly influenced the selectivity of β-ether phenolic dimer cleavage to generate sinapaldehyde and coniferaldehyde, monomers not usually produced by oxidative methods. Time-course studies on two key intermediates provided insight into the reaction pathway. Owing to the broad scope of this oxidation system and the insight gleaned with regard to its mechanism, this strategy could be adapted and applied in a general sense to the production of useful aromatic chemicals from phenolics and lignin. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Concerns, perceived need and competing priorities: a qualitative exploration of decision-making and non-participation in a population-based flexible sigmoidoscopy screening programme to prevent colorectal cancer

    PubMed Central

    Hall, N; Birt, L; Rees, C J; Elliot, S; Ritchie, M; Weller, D; Rubin, G

    2016-01-01

    Objective Optimising uptake of colorectal cancer (CRC) screening is important to achieve projected health outcomes. Population-based screening by flexible sigmoidoscopy (FS) was introduced in England in 2013 (NHS Bowel scope screening). Little is known about reactions to the invitation to participate in FS screening, as offered within the context of the Bowel scope programme. We aimed to investigate responses to the screening invitation to inform understanding of decision-making, particularly in relation to non-participation in screening. Design Qualitative analysis of semistructured in-depth interviews and written accounts. Participants and setting People from 31 general practices in the North East and East of England invited to attend FS screening as part of NHS Bowel scope screening programme were sent invitations to take part in the study. We purposively sampled interviewees to ensure a range of accounts in terms of beliefs, screening attendance, sex and geographical location. Results 20 screeners and 25 non-screeners were interviewed. Written responses describing reasons for, and circumstances surrounding, non-participation from a further 28 non-screeners were included in the analysis. Thematic analysis identified a range of reactions to the screening invitation, decision-making processes and barriers to participation. These include a perceived or actual lack of need; inability to attend; anxiety and fear about bowel preparation, procedures or hospital; inability or reluctance to self-administer an enema; beliefs about low susceptibility to bowel cancer or treatment and understanding of harm and benefits. The strength, rather than presence, of concerns about the test and perceived need for reassurance were important in the decision to participate for screeners and non-screeners. Decision-making occurs within the context of previous experiences and day-to-day life. Conclusions Understanding the reasons for non-participation in FS screening can help inform strategies to improve uptake and may be transferable to other screening programmes. PMID:27836872

  6. EarthScope National Office Education and Outreach Program: 2013 Update on Activities and Outcomes

    NASA Astrophysics Data System (ADS)

    Semken, S. C.; Robinson, S.; Bohon, W.; Schwab, P.; Arrowsmith, R.; Garnero, E. J.; Fouch, M. J.; Pettis, L.; Baumback, D.; Dick, C.

    2013-12-01

    The EarthScope Program (www.earthscope.org) funded by the National Science Foundation, fosters interdisciplinary exploration of the geologic structure and evolution of the North American continent by means of seismology, geodesy, magnetotellurics, in-situ fault-zone sampling, geochronology, and high-resolution topographic measurements. Data and findings from EarthScope continue to transform geoscientific studies throughout the Earth, enhance understanding and mitigation of hazards, and inform applications of geoscience toward environmental sustainability. The EarthScope Program also marshals significant resources and opportunities for education and outreach (E&O) in the Earth system sciences. The EarthScope National Office (ESNO) at Arizona State University serves all EarthScope stakeholders, including the EarthScope Steering Committee, researchers, educators, students, and the general public. ESNO supports and promotes E&O through social media and web-hosted resources, newsletters and published articles, E&O workshops for informal educators (interpreters), assistance to grassroots K-12 STEM teacher professional development projects (typically led by EarthScope researchers), continuing education for researchers, collaborations with other Earth-science E&O providers, and biannual national conferences. The EarthScope E&O program at ESNO leads and supports wide dissemination of the data, findings, and legacy of EarthScope. Notable activities in 2013 include expansion of social-media and web-based content, two Interpretive Workshops in the eastern United States, the Great ShakeOut, the EarthScope National Meeting in Raleigh, and continuing partnerships with affiliated E&O providers. The EarthScope National Office is supported by the National Science Foundation under grants EAR-1101100 and EAR-1216301. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

  7. 22 CFR 226.80 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Additional Provisions For Awards to Commercial Organizations § 226.80 Scope of subpart. This subpart contains additional provisions that apply to awards to commercial organizations. These provisions...

  8. 48 CFR 750.7100 - Scope of subpart.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Scope of subpart. 750.7100 Section 750.7100 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS Extraordinary Contractual Actions To Protect Foreign Policy...

  9. 48 CFR 750.7100 - Scope of subpart.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Scope of subpart. 750.7100 Section 750.7100 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS Extraordinary Contractual Actions To Protect Foreign Policy...

  10. 48 CFR 750.7100 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Scope of subpart. 750.7100 Section 750.7100 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS Extraordinary Contractual Actions To Protect Foreign Policy...

  11. Subcommittee on New Highway Materials materials and technologies : 2006 summary report.

    DOT National Transportation Integrated Search

    2006-09-01

    Scope: The subcommittee has a scope for them to identify the needs and types of new : highway materials and technologies required and to provide the appraisal, : evaluation, and specification development for new materials and technologies : being pro...

  12. Automated and Autonomous Systems for Combat Service Support: Scoping Study and Technology Prioritisation

    DTIC Science & Technology

    2016-10-01

    workshop, and use case development for automated and autonomous systems for CSS. The scoping study covers key concepts and trends, a technology scan, and...requirements and delimiters for the selected technologies. The report goes on to present detailed use cases for two technologies of interest: semi...selected use cases . As a result of the workshop, the large list of technologies and applications from the scoping study was narrowed down to the top

  13. What Is Known about School-Based Interventions for Health Promotion and Their Impact in Developing Countries? A Scoping Review of the Literature

    ERIC Educational Resources Information Center

    Mukamana, O.; Johri, M.

    2016-01-01

    Schools can play an important role in health promotion mainly by improving students' health literacy, behaviors and academic achievements. School-based health promotion can be particularly valuable in developing countries facing the challenges of low health literacy and high burden of disease. We conducted a scoping review of the published…

  14. Addressing female genital mutilation in Europe: a scoping review of approaches to participation, prevention, protection, and provision of services.

    PubMed

    Baillot, Helen; Murray, Nina; Connelly, Elaine; Howard, Natasha

    2018-02-08

    Public and policy attention to female genital mutilation (FGM) in diaspora communities has increased in Europe, but research remains limited and misinformation abounds. As a first step to addressing these issues, this study explored FGM prevention and response interventions in Europe, using a scoping literature review and key informant interviews. A scoping study design was selected, using Arksey and O'Malley's six-stage scoping framework to review identified sources. Key informant interviews were used to inform and add depth to literature findings. Findings were summarised thematically, guided by the Scottish Government's '4Ps' framework for tackling violence against women (i.e. participation, prevention, protection, providing services). Seventy literature sources, of 1095 screened, plus 16 individual and 3 group interview sources were included. Several countries have developed promising interventions supporting FGM resistance and recovery. However, gaps remain including community participation, professional knowledge and linkages, and evaluation of approaches. This scoping review is an initial attempt to describe available primary evidence on European initiatives responding to FGM. Further research is required to determine whether interventions are effective, while policy and practice development must be shaped and driven by the experiences, needs, and views of affected communities.

  15. 15 CFR 996.1 - Purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES QUALITY ASSURANCE AND CERTIFICATION REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES General § 996.1 Purpose and scope. The National Oceanic and Atmospheric Administration (NOAA) was mandated to develop and implement a quality assurance program that is...

  16. 15 CFR 996.1 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES QUALITY ASSURANCE AND CERTIFICATION REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES General § 996.1 Purpose and scope. The National Oceanic and Atmospheric Administration (NOAA) was mandated to develop and implement a quality assurance program that is...

  17. 15 CFR 996.1 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES QUALITY ASSURANCE AND CERTIFICATION REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES General § 996.1 Purpose and scope. The National Oceanic and Atmospheric Administration (NOAA) was mandated to develop and implement a quality assurance program that is...

  18. 15 CFR 996.1 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES QUALITY ASSURANCE AND CERTIFICATION REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES General § 996.1 Purpose and scope. The National Oceanic and Atmospheric Administration (NOAA) was mandated to develop and implement a quality assurance program that is...

  19. 32 CFR 989.19 - Draft EIS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... as when there has been a significant change in circumstances, development of significant new... proposed action. Significant new information leading to public controversy regarding the scope after the scoping process is such a changed circumstance. An additional public comment period may also be necessary...

  20. 15 CFR 90.1 - Scope and applicability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CENSUS, DEPARTMENT OF COMMERCE PROCEDURE FOR CHALLENGING POPULATION ESTIMATES § 90.1 Scope and... number of people residing in states and their governmental units. In general, these estimates are developed by updating the population counts produced in the most recent decennial census with demographic...

  1. 45 CFR 1355.10 - Scope.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Scope. 1355.10 Section 1355.10 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION ON CHILDREN, YOUTH AND FAMILIES, FOSTER CARE MAINTENANCE...

  2. 45 CFR 1355.10 - Scope.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Scope. 1355.10 Section 1355.10 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION ON CHILDREN, YOUTH AND FAMILIES, FOSTER CARE MAINTENANCE...

  3. 45 CFR 1355.10 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Scope. 1355.10 Section 1355.10 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION ON CHILDREN, YOUTH AND FAMILIES, FOSTER CARE MAINTENANCE...

  4. 24 CFR 599.1 - Applicability and scope.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND... scope. (a) This part establishes requirements and procedures applicable to the designation of Renewal Communities (RCs) through December 31, 2001, authorized under Subchapter X of the Internal Revenue Code of...

  5. 24 CFR 599.1 - Applicability and scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND... scope. (a) This part establishes requirements and procedures applicable to the designation of Renewal Communities (RCs) through December 31, 2001, authorized under Subchapter X of the Internal Revenue Code of...

  6. 24 CFR 599.1 - Applicability and scope.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND... scope. (a) This part establishes requirements and procedures applicable to the designation of Renewal Communities (RCs) through December 31, 2001, authorized under Subchapter X of the Internal Revenue Code of...

  7. AccessScope project: Accessible light microscope for users with upper limb mobility or visual impairments.

    PubMed

    Mansoor, Awais; Ahmed, Wamiq M; Samarapungavan, Ala; Cirillo, John; Schwarte, David; Robinson, J Paul; Duerstock, Bradley S

    2010-01-01

    A web-based application was developed to remotely view slide specimens and control all functions of a research-level light microscopy workstation, called AccessScope. Students and scientists with upper limb mobility and visual impairments are often unable to use a light microscope by themselves and must depend on others in its operation. Users with upper limb mobility impairments and low vision were recruited to assist in the design process of the AccessScope personal computer (PC) user interface. Participants with these disabilities were evaluated in their ability to use AccessScope to perform microscopical tasks. AccessScope usage was compared with inspecting prescanned slide images by grading participants' identification and understanding of histological features and knowledge of microscope operation. With AccessScope subjects were able to independently perform common light microscopy functions through an Internet browser by employing different PC pointing devices or accessibility software according to individual abilities. Subjects answered more histology and microscope usage questions correctly after first participating in an AccessScope test session. AccessScope allowed users with upper limb or visual impairments to successfully perform light microscopy without assistance. This unprecedented capability is crucial for students and scientists with disabilities to perform laboratory coursework or microscope-based research and pursue science, technology, engineering, and mathematics fields.

  8. Llnking the EarthScope Data Virtual Catalog to the GEON Portal

    NASA Astrophysics Data System (ADS)

    Lin, K.; Memon, A.; Baru, C.

    2008-12-01

    The EarthScope Data Portal provides a unified, single-point of access to EarthScope data and products from USArray, Plate Boundary Observatory (PBO), and San Andreas Fault Observatory at Depth (SAFOD) experiments. The portal features basic search and data access capabilities to allow users to discover and access EarthScope data using spatial, temporal, and other metadata-based (data type, station specific) search conditions. The portal search module is the user interface implementation of the EarthScope Data Search Web Service. This Web Service acts as a virtual catalog that in turn invokes Web services developed by IRIS (Incorporated Research Institutions for Seismology), UNAVCO (University NAVSTAR Consortium), and GFZ (German Research Center for Geosciences) to search for EarthScope data in the archives at each of these locations. These Web Services provide information about all resources (data) that match the specified search conditions. In this presentation we will describe how the EarthScope Data Search Web service can be integrated into the GEONsearch application in the GEON Portal (see http://portal.geongrid.org). Thus, a search request issued at the GEON Portal will also search the EarthScope virtual catalog thereby providing users seamless access to data in GEON as well as the Earthscope via a common user interface.

  9. Fluorous tagging strategy for solution-phase synthesis of small molecules, peptides and oligosaccharides

    PubMed Central

    Zhang, Wei

    2005-01-01

    The purification of reaction mixtures is a slow process in organic synthesis, especially during the production of large numbers of analogs and compound libraries. Phase-tag methods such as solid-phase synthesis and fluorous synthesis, provide efficient ways of addressing the separation issue. Fluorous synthesis employs functionalized perfluoroalkyl groups attached to substrates or reagents. The separation of the resulting fluorous molecules can be achieved using strong and selective fluorous liquid-liquid extraction, fluorous silica gel-based solid-phase extraction or high-performance liquid chromatography. Fluorous technology is a novel solution-phase method, which has the advantages of fast reaction times in homogeneous environments, being readily adaptable to literature conditions, having easy intermediate analysis, and having flexibility in reaction scale and scope. In principle, any synthetic methods that use a solid-support could be conducted in solution-phase by replacing the polymer linker with a corresponding fluorous tag. This review summarizes the progress of fluorous tags in solution-phase synthesis of small molecules, peptides and oligosaccharides. PMID:15595439

  10. Carbon Dioxide-Mediated C(sp3)-H Arylation of Amine Substrates.

    PubMed

    Kapoor, Mohit; Liu, Daniel; Young, Michael C

    2018-05-25

    Elaborating amines via C-H functionalization has been an important area of research over the past decade but has generally relied on an added directing group or sterically hindered amine approach. Since free-amine-directed C(sp 3 )-H activation is still primarily limited to cyclization reactions and to improve the sustainability and reaction scope of amine-based C-H activation, we present a strategy using CO 2 in the form of dry ice that facilitates intermolecular C-H arylation. This methodology has been used to enable an operationally simple procedure whereby 1° and 2° aliphatic amines can be arylated selectively at their γ-C-H positions. In addition to potentially serving as a directing group, CO 2 has also been demonstrated to curtail the oxidation of sensitive amine substrates.

  11. N-Tosylhydrazone directed annulation via C-H/N-N bond activation in Ru(ii)/PEG-400 as homogeneous recyclable catalytic system: a green synthesis of isoquinolines.

    PubMed

    Deshmukh, Dewal S; Bhanage, Bhalchandra M

    2018-06-21

    A green and sustainable methodology for the synthesis of isoquinolines using Ru(ii)/PEG-400 as a homogeneous recyclable catalytic system has been demonstrated. N-Tosylhydrazone, a rarely explored directing group, has been successfully employed for an annulation type of reaction with alkynes via C-H/N-N activation. A short reaction time with a simple extraction procedure, a wide substrate scope with high yields of products, easily prepared substrates, biodegradable solvent, and scalability up to the gram level enhance the efficiency and sustainability of the proposed protocol. Further, the expensive ruthenium-based homogeneous catalytic system could be reused up to a fourth consecutive cycle without any loss in its activity.

  12. Practical Stannylation of Allyl Acetates Catalyzed by Nickel with Bu3 SnOMe.

    PubMed

    Komeyama, Kimihiro; Itai, Yuuhei; Takaki, Ken

    2016-06-27

    A practical and scalable nickel-catalyzed allylic stannylation of allyl acetates with Bu3 SnOMe is described. A variety of acyclic and cyclic allyl acetates, even with base-sensitive moieties, undergoes the stannylation by using NiBr2 /4,4'-di-tert-butylbipyridine (dtbpy)/Mn catalyst system to afford highly functionalized allyl stannanes with excellent regioselectivity and yields. Furthermore, the scope of protocol is also extended by the reaction of propargyl acetates, giving rise to propargyl or allenyl stannanes. Additionally, a unique diastereoselectivity using the nickel catalyst different from the palladium was demonstrated for the stannylation of cyclic allyl acetates. In the reaction, inexpensive and stable nickel complexes, abundant reductant (Mn), and atom-economical stannyl source were used. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Concise copper-catalyzed synthesis of tricyclic biaryl ether-linked aza-heterocyclic ring systems.

    PubMed

    Mestichelli, Paola; Scott, Matthew J; Galloway, Warren R J D; Selwyn, Jamie; Parker, Jeremy S; Spring, David R

    2013-11-01

    A new method for the synthesis of tricyclic biaryl ether-linked ring systems incorporating seven-, eight-, and nine-membered ring amines is presented. In the presence of catalytic quantities of copper(I), readily accessible acyclic precursors undergo an intramolecular carbon-oxygen bond-forming reaction facilitated by a "templating" chelating nitrogen atom. The methodology displays a broad substrate scope, is practical, and generates rare and biologically interesting tricyclic heteroaromatic products that are difficult to access by other means.

  14. Preparation of Benzo[c]carbazol-6-amines via Manganese-Catalyzed Enaminylation of 1-(Pyrimidin-2-yl)-1H-indoles with Ketenimines and Subsequent Oxidative Cyclization.

    PubMed

    Zhou, Xiaorong; Li, Zhenmin; Zhang, Zhiyin; Lu, Ping; Wang, Yanguang

    2018-03-02

    Manganese-catalyzed C 2 -H enaminylation of 1-(pyrimidin-2-yl)-1H-indoles with ketenimines is reported. The reaction provided 2-enaminylated indole derivatives in moderate to excellent yields with a broad substrate scope. A migration of the directing group pyrimidinyl occurred during this process. The synthesized 2-enaminyl indoles could be conveniently converted into 5-aryl-7H-benzo[c]carbazol-6-amines.

  15. High-Valent Organometallic Copper and Palladium in Catalysis

    PubMed Central

    Hickman, Amanda J.; Sanford, Melanie S.

    2015-01-01

    Preface Copper and palladium catalysts are critically important for numerous commercial chemical processes. Improvements in the activity, selectivity, and scope of these catalysts have the potential to dramatically reduce the environmental impact and increase the sustainability of chemical reactions. One rapidly emerging strategy to achieve these goals is to exploit “high-valent” copper and palladium intermediates in catalysis. This review describes exciting recent advances involving both the fundamental chemistry and the applications of these high-valent metal complexes in numerous synthetically useful catalytic transformations. PMID:22498623

  16. A new hypercrosslinked supermicroporous polymer, with scope for sulfonation, and its catalytic potential for the efficient synthesis of biodiesel at room temperature.

    PubMed

    Bhunia, Subhajit; Banerjee, Biplab; Bhaumik, Asim

    2015-03-25

    We have designed a new hypercrosslinked supermicroporous polymer (HMP-1) with a BET surface area of 913 m(2) g(-1) by FeCl3 via a catalyzed Friedel-Crafts alkylation reaction between carbazole and α,α'-dibromo-p-xylene. Upon sulfonation HMP-1 yielded a very efficient solid acid catalyst for the production of biodiesels via esterification/transesterification of free fatty acids (FFA)/esters at room temperature.

  17. Slow histidine H/D exchange protocol for thermodynamic analysis of protein folding and stability using mass spectrometry.

    PubMed

    Tran, Duc T; Banerjee, Sambuddha; Alayash, Abdu I; Crumbliss, Alvin L; Fitzgerald, Michael C

    2012-02-07

    Described here is a mass spectrometry-based protocol to study the thermodynamic stability of proteins and protein-ligand complexes using the chemical denaturant dependence of the slow H/D exchange reaction of the imidazole C(2) proton in histidine side chains. The protocol is developed using several model protein systems including: ribonuclease (Rnase) A, myoglobin, bovine carbonic anhydrase (BCA) II, hemoglobin (Hb), and the hemoglobin-haptoglobin (Hb-Hp) protein complex. Folding free energies consistent with those previously determined by other more conventional techniques were obtained for the two-state folding proteins, Rnase A and myoglobin. The protocol successfully detected a previously observed partially unfolded intermediate stabilized in the BCA II folding/unfolding reaction, and it could be used to generate a K(d) value of 0.24 nM for the Hb-Hp complex. The compatibility of the protocol with conventional mass spectrometry-based proteomic sample preparation and analysis methods was also demonstrated in an experiment in which the protocol was used to detect the binding of zinc to superoxide dismutase in the yeast cell lysate sample. The yeast cell sample analyses also helped define the scope of the technique, which requires the presence of globally protected histidine residues in a protein's three-dimensional structure for successful application. © 2011 American Chemical Society

  18. Cationic Zn-Porphyrin Polymer Coated onto CNTs as a Cooperative Catalyst for the Synthesis of Cyclic Carbonates.

    PubMed

    Jayakumar, Sanjeevi; Li, He; Chen, Jian; Yang, Qihua

    2018-01-24

    The development of solid catalysts containing multiple active sites that work cooperatively is very attractive for biomimetic catalysis. Herein, we report the synthesis of bifunctional catalysts by supporting cationic porphyrin-based polymers on carbon nanotubes (CNTs) using the direct reaction of 5,10,15,20-tetrakis(4-pyridyl)porphyrin zinc(II), di(1H-imidazol-1-yl)methane, and 1,4-bis(bromomethyl)benzene in the presence of CNTs. The bifunctional catalysts could efficiently catalyze the cycloaddition reaction of epoxides and CO 2 under solvent-free conditions with porphyrin zinc(II) as the Lewis acid site and a bromine anion as a nucleophilic agent working in a cooperative way. Furthermore, a relative amount of porphyrin zinc(II) and quaternary ammonium bromide could be facilely adjusted for facilitating cooperative behavior. The bifunctional catalyst with a TOF up to 2602 h -1 is much more active than the corresponding homogeneous counterpart and is one of the most active heterogeneous catalysts ever reported under cocatalyst-free conditions. The high activity is mainly attributed to the enhanced cooperation effect of the bifunctional catalyst. With a wide substrate scope, the bifunctional catalyst could be stably recycled. This work demonstrates a new approach for the generation of a cooperative activation effect for solid catalysts.

  19. National Geographic FieldScope: Tools for Engaging a Range of Audiences in Citizen Science

    NASA Astrophysics Data System (ADS)

    OConnor, S.; Takaki, E.

    2013-12-01

    Recognizing the promise of projects that engage non-scientists in scientific research as a context for informal science learning, National Geographic set out in 2009 to develop a technology infrastructure to support public participation in scientific research (PPSR), or citizen science, projects. As a result, NG has developed a web-based platform called FieldScope to host projects in which geographically distributed participants submit local observations or measurements to a shared database. This project is motivated by the observation that historically citizen science initiatives have been siloed using different technologies, and that these projects rarely provide participants with the opportunity to participate in data analysis or any other aspects of the scientific process except for collecting and contributing data. Therefore, FieldScope has been designed to support data visualization and analysis using geospatial technologies and aims to develop social networking tools for communicating and discussing findings. Since educational impact is the project's primary priority, FieldScope is also being designed with usability by novices in mind. In addition to engaging novices in participation in citizen science, the design of the application is also meant to engage students and others in working with geospatial technologies, in this case, web-based GIS. The project's goal is to create a single, powerful infrastructure for PPSR projects that any organization can use to create their own project and support their own community of participants. The FieldScope environment will serve as a hosting environment for PPSR projects following the model of hosted communities of practice that has become widespread on the web. The goal is to make FieldScope a publicly-available resource for any PPSR project on a no- or low-cost basis. It will also make synergies possible between projects that are collecting related data in the same geographic area. NG is now in the fourth year of an NSF grant to bring this vision for FieldScope to life. The project is structured around key collaborations with 'conveners' of existing citizen science initiatives. These existing initiatives include Project BudBurst, the Association of Zoos and Aquariums FrogWatch USA, and the Alice Ferguson Fund's Trash Free Potomac Initiative. These groups are serving as testbed partners, building their citizen science projects with the FieldScope development tools and hosting their communities within the FieldScope infrastructure. Through outcomes research and evaluation, these testbeds will provide much-needed evidence about the value of citizen science for learning and the conditions that can maximize those outcomes. Presenters will share findings to date of the project, including a demonstration of the technology using examples from our convening partners from the NSF project, as well as other communities using FieldScope, ranging from citizen science initiatives in the Yukon River watershed aimed at engaging indigenous Alaskan populations to a wide-spread initiative across the Chesapeake Bay watershed designed for students and environmental education program participants.

  20. Recalling Hofstadter and Hardy's Classic: The Development and Scope of Higher Education in the United States. IHE Perspectives.

    ERIC Educational Resources Information Center

    Fincher, Cameron

    This paper reviews what it calls a classic book in the field of higher education, 1952's "The Development and Scope of Higher Education," by Richard Hofstadter and C. DeWitt Hardy. The paper describes the main points of the book, which was written as part of a series, "Nature and Needs of Higher Education," prepared for the…

  1. 14 CFR 1274.102 - Scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Scope. 1274.102 Section 1274.102 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION COOPERATIVE AGREEMENTS WITH COMMERCIAL FIRMS...) Provide technology transfer from the Government to the recipient; or (3) Develop a capability among U.S...

  2. 28 CFR 544.70 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Purpose and scope. 544.70 Section 544.70 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT EDUCATION... federal institution who does not have a verified General Educational Development (GED) credential or high...

  3. 24 CFR 901.1 - Purpose, program scope and applicability.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... receivership agreement, if applicable). (5) To ensure quality management results from a contract between an AME... URBAN DEVELOPMENT PUBLIC HOUSING MANAGEMENT ASSESSMENT PROGRAM § 901.1 Purpose, program scope and applicability. (a) Purpose. This part establishes the Public Housing Management Assessment Program (PHMAP) to...

  4. 24 CFR 27.2 - Scope and applicability.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Development NONJUDICIAL FORECLOSURE OF MULTIFAMILY AND SINGLE FAMILY MORTGAGES Nonjudicial Foreclosure of Multifamily Mortgages § 27.2 Scope and applicability. (a) Under the Act and this subpart, the Secretary may foreclose on any defaulted Secretary-held multifamily mortgage encumbering real estate in any State. The...

  5. 24 CFR 27.2 - Scope and applicability.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Development NONJUDICIAL FORECLOSURE OF MULTIFAMILY AND SINGLE FAMILY MORTGAGES Nonjudicial Foreclosure of Multifamily Mortgages § 27.2 Scope and applicability. (a) Under the Act and this subpart, the Secretary may foreclose on any defaulted Secretary-held multifamily mortgage encumbering real estate in any State. The...

  6. 24 CFR 27.2 - Scope and applicability.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Development NONJUDICIAL FORECLOSURE OF MULTIFAMILY AND SINGLE FAMILY MORTGAGES Nonjudicial Foreclosure of Multifamily Mortgages § 27.2 Scope and applicability. (a) Under the Act and this subpart, the Secretary may foreclose on any defaulted Secretary-held multifamily mortgage encumbering real estate in any State. The...

  7. 24 CFR 27.2 - Scope and applicability.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Development NONJUDICIAL FORECLOSURE OF MULTIFAMILY AND SINGLE FAMILY MORTGAGES Nonjudicial Foreclosure of Multifamily Mortgages § 27.2 Scope and applicability. (a) Under the Act and this subpart, the Secretary may foreclose on any defaulted Secretary-held multifamily mortgage encumbering real estate in any State. The...

  8. 48 CFR 752.7000 - Scope of subpart.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Section 752.7000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of USAID Contract Clauses 752.7000 Scope of subpart. Subpart 752.70 contains the text of USAID-specific contract clauses for which there is no FAR...

  9. 48 CFR 752.7000 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 752.7000 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of USAID Contract Clauses 752.7000 Scope of subpart. Subpart 752.70 contains the text of USAID-specific contract clauses for which there is no FAR...

  10. Interprofessional online learning for primary healthcare: findings from a scoping review.

    PubMed

    Reeves, Scott; Fletcher, Simon; McLoughlin, Clodagh; Yim, Alastair; Patel, Kunal D

    2017-08-04

    This article presents the findings from a scoping review which explored the nature of interprofessional online learning in primary healthcare. The review was informed by the following questions: What is the nature of evidence on online postgraduate education for primary healthcare interprofessional teams? What learning approaches and study methods are used in this context? What is the range of reported outcomes for primary healthcare learners, their organisations and the care they deliver to patients/clients? The review explored the global literature on interprofessional online learning in primary healthcare settings. The review found that the 23 included studies employed a range of different e-learning methods with contrasting course durations, use of theory, participant mix, approaches to accreditation and assessment of learning. Most of the included studies reported outcomes associated with learner reactions and positive changes in participant attitudes/perceptions and improvement in knowledge/skills as a result of engagement in an e-learning course. In contrast, fewer studies reported changes in participant behaviours, changes in organisational practice and improvements to patients/clients. A number of educational, methodological and outcome implications are be offered. E-learning can enhance an education experience, support development, ease time constraints, overcome geographic limitations and can offer greater flexibility. However, it can also contribute to the isolation of learners and its benefits can be negated by technical problems. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Scoping meta-review: introducing a new methodology.

    PubMed

    Sarrami-Foroushani, Pooria; Travaglia, Joanne; Debono, Deborah; Clay-Williams, Robyn; Braithwaite, Jeffrey

    2015-02-01

    For researchers, policymakers, and practitioners facing a new field, undertaking a systematic review can typically present a challenge due to the enormous number of relevant papers. A scoping review is a method suggested for addressing this dilemma; however, scoping reviews present their own challenges. This paper introduces the "scoping meta-review" (SMR) for expanding current methodologies and is based on our experiences in mapping the field of consumer engagement in healthcare. During this process, we developed the novel SMR method. An SMR combines aspects of a scoping review and a meta-review to establish an evidence-based map of a field. Similar to a scoping review, an SMR offers a practical and flexible methodology. However, unlike in a traditional scoping review, only systematic reviews are included. Stages of the SMR include: undertaking a preliminary nonsystematic review; building a search strategy; interrogating academic literature databases; classifying and excluding studies based on titles and abstracts; saving the refined database of references; revising the search strategy; selecting and reviewing the full text papers; and thematically analyzing the selected texts and writing the report. The main benefit of an SMR is to map a new field based on high-level evidence provided by systematic reviews. © 2014 Wiley Periodicals, Inc.

  12. Engaging the Geodetic and Geoscience Communities in EarthScope Education and Outreach

    NASA Astrophysics Data System (ADS)

    Charlevoix, D. J.; Berg, M.; Morris, A. R.; Olds, S. E.

    2013-12-01

    UNAVCO is NSF's geodetic facility and operates as a university-governed consortium dedicated to facilitating geoscience research and education, including the support of EarthScope. The Education and Community Engagement program at UNAVCO provides support for broader impacts both externally to the broader University and EarthScope community as well as internally to the UNAVCO. During the first 10 years of EarthScope UNAVCO has engaged in outreach and education activities across the EarthScope footprint ranging from outreach to formal and informal educators and interpreters, to technical training for university faculty and researchers. UNAVCO works jointly with the EarthScope National Office and IRIS while simultaneously maintaining and developing an independent engagement and education program. UNAVCO provides training in the form of technical short courses to researchers including graduate students and early-career professionals, and conducts educational workshops for K-12 educators. A suite of educational materials focused on the integration of EarthScope data into curriculum materials is available from UNAVCO and will soon expand the undergraduate offerings to include a broader suite of geodesy applications activities for undergraduate students. UNAVCO provides outreach materials and in support of EarthScope including summaries of research project and campaign highlights, science snapshots featuring summaries of scientific advancements made possible by UNAVCO services and non-technical communications via social media. UNAVCO also provides undergraduate students exposure to EarthScope science research participation in a year-long research internship managed by UNAVCO (Research Experiences in Solid Earth Science for Students - RESESS).

  13. EDITORIAL: New scope for Journal of Physics D: Applied Physics New scope for Journal of Physics D: Applied Physics

    NASA Astrophysics Data System (ADS)

    Roche, Olivia; Margaritondo, Giorgio

    2011-10-01

    After five years of significant growth and development, and with the Impact Factor (IF) now firmly placed over 2.0, Journal of Physics D: Applied Physics (JPhysD) has seen a double change at the helm in the last 12 months. Giorgio Margaritondo from École Polytechnique Fédérale de Lausanne, Switzerland took over as Editor-in-Chief from Pallab Bhattacharya, while Olivia Roche took over as Publisher from Sarah Quin. We inherited a strong, successful journal. With its IF of 2.105, excellent publication times and flexible, responsive management, JPhysD has established itself as the place to publish high-quality research papers in applied physics. Having introduced Fast Track Communications (FTCs) in 2008, we also became an outlet for short, high-impact letter-like articles. FTCs, with their particularly strict refereeing, add an extra mark of quality to the content. We are keen to continue developing and strengthening the journal to make it the first choice for authors and readers. We are lucky to be working in the exciting, rapidly-changing field of applied physics. The pace of development can sometimes be breathtaking. One of our first actions on taking over the journal was to look again at its scope. We felt it was time to respond to all the recent developments, to ensure that our scope encompasses the latest, cutting-edge research topics—so that it matches the reality of applied physics today. The first issue of the journal that will see this new scope implemented will be issue 41 of this volume. We would like to thank the entire Editorial Board for their hard work during this scope review. The greatest change during this review has been the merging of two sections, 'Functional surfaces and interfaces' and 'Structure and properties of matter', into a new section entitled 'Condensed matter, interfaces and related nanostructures'. This change reflects the significant developments in these connected fields in recent years, particularly the natural evolution of surface and interface science—and much of condensed matter physics—towards nanoscience. We are sure this merged section will bring the authors' work in both of these sections to a broader audience. All sections have seen some additions to, and removals from, the scope. A full copy of the new scope can be found at the end of this editorial. Some of the areas from which we are particularly keen to receive more papers include: photovoltaics, terahertz science and technology, plasmonics, spintronics, bulk magnetic materials, biomagnetism, graphene, plasma medicine and plasma propulsion. Many others are closely monitored as potential developments and we will act rapidly whenever necessary to avoid missing opportunities. As part of these changes, we will be asking all authors to explain their choice of journal section within the new scope. We will also ask authors to submit a short statement of the applications or potential applications of their work. This will allow us to assess the suitability of the research for the journal but will also allow us to highlight the most exciting research we publish, ensuring it gets the highest possible visibility. We would like to take this opportunity to thank our hard-working and dedicated publishing team and Editorial Board. We would also like to thank the authors and referees of JPhysD, without whom the journal could not exist. We believe these changes will allow further strengthening, development and growth of the journal and we look forward to a positive future for JPhysD.

  14. 45 CFR 1301.1 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false Purpose and scope. 1301.1 Section 1301.1 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

  15. 45 CFR 1301.1 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Purpose and scope. 1301.1 Section 1301.1 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

  16. 45 CFR 1305.1 - Purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Purpose and scope. 1305.1 Section 1305.1 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

  17. 45 CFR 1301.1 - Purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Purpose and scope. 1301.1 Section 1301.1 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

  18. 45 CFR 1305.1 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false Purpose and scope. 1305.1 Section 1305.1 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

  19. 45 CFR 1305.1 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Purpose and scope. 1305.1 Section 1305.1 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

  20. 24 CFR 811.101 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT (SECTION 8 HOUSING ASSISTANCE PROGRAMS, SECTION 202 DIRECT LOAN PROGRAM, SECTION 202... PROGRAM) TAX EXEMPTION OF OBLIGATIONS OF PUBLIC HOUSING AGENCIES AND RELATED AMENDMENTS § 811.101 Purpose and scope. (a) The purpose of this part is to provide a basis for determining tax exemption of...

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