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Sample records for ethyl vinyl ether

  1. Elastic electron scattering by ethyl vinyl ether

    SciTech Connect

    Khakoo, M. A.; Hong, L.; Kim, B.; Winstead, C.; McKoy, V.

    2010-02-15

    We report measured and calculated results for elastic scattering of low-energy electrons by ethyl vinyl ether (ethoxyethene), a prototype system for studying indirect dissociative attachment processes that may play a role in DNA damage. The integral cross section displays the expected {pi}{sup *} shape resonance. The agreement between the calculated and measured cross sections is generally good.

  2. Effect of solvents on the radiation-induced polymerization of ethyl and isopropyl vinyl ethers. [gamma rays

    SciTech Connect

    Hsieh, W.C.; Kubota, H.; Squire, D.R.; Stannett, V.

    1980-09-01

    The radiation-induced cationic polymerization of ethyl and isopropyl vinyl ethers was studied in a variety of solvents. The propagation rate constants were estimated and found to vary widely with the nature of the solvent. In particular, a good linear relationship existed between the logarithms of the rate constants and the reciprocal of the dielectric constants. The lowest rates were those of the highest dielectric constant solvents. These results have been interpreted in terms of the Laidler and Eyring theory of ion-molecule reactions. Isopropyl vinyl ether polymerizes much faster than ethyl vinyl ether, although the rates approach the same value at infinite dielectric constant. In contrast, free carbenium ion polymerizations initiated by stable carbenium ion salts in methylene chloride solution had similar values for both monomers. A comparison is made between the rate constants obtained with both methods of initiation.

  3. Ethyl ether

    Integrated Risk Information System (IRIS)

    Ethyl ether ; CASRN 60 - 29 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  4. Effect of solvents on the radiation-induced polymerization of ethyl and isopropyl vinyl ethers

    SciTech Connect

    Hsieh, W.C.

    1981-01-01

    The effect of solvents on the radiation-induced cationic polymerization of ethyl and isopropyl vinyl ethers (EVE and IPVE, respectively) was investigated. EVE and IPVE polymerizations were carried out in bulk and in solution under superdry conditions in which polar impurities, especially water, have been reduced to negligible levels. This was accomplished by means of a sodium mirror technique using joint free baked out glass equipment and high vacuum. Plots of the monomer conversions and irradiation times were obtained for EVE and IPVE polymerizations in bulk and in benzene solution at constant monomer concentrations. The monomer concentration dependence of the polymerization rate was studied for EVE polymerization in bulk and in benzene, diethlyl ether, diglyme and methylene chloride, and for IPVE polymerization in bulk and in benzene. Solvent effect on the estimated propagating rate constants was examined for EVE and IPVE polymerization in bulk and in solution. The effect of temperature on the polymerization rate was also investigated for EVE polymerization in bulk ad in benzene, diethyl and diisopropyl ethers, methylene chloride and nitromethane, and for IPVE ploymerization in bulk and in benzene.

  5. Vinyl ether silicones

    SciTech Connect

    Herzig, C.; Dauth, J.; Deubzer, B.; Weis, J.

    1995-12-01

    Siloxanes with vinyl ether groups are prepared by hydrosilylation reaction of dihydrosiloxanes with divinyl ethers in excess. Different stoichiometry, produces linear copolymers of different viscosities and double bond concentrations always with an active vinyl ether group at each chain end. Polymerisations triggered by UV light were done with mixtures of these compounds and a series of onium salts. Very fast cure is observed even with low doses at 290 nm. V.E. silicones are found to cure essentially quantitative. The comparison with other highly reactive cationic monomers revealed that compounds are among the fastest curing prepolymers in cationic chemistry.

  6. Computational study on the mechanisms and rate constants of the OH-initiated oxidation of ethyl vinyl ether in atmosphere.

    PubMed

    Han, Dandan; Cao, Haijie; Li, Jing; Li, Mingyue; He, Maoxia; Hu, Jingtian

    2014-09-01

    The hydroxylation reactions of ethyl vinyl ether (EVE) in the present of O2 and NO are analyzed by using MPWB1K/6-311++G(3df,2p)//MPWB1K/6-31+G(d,p) level of theory. According to the calculated thermodynamic data, the detailed reaction mechanisms of EVE and OH are proposed. All of the ten possible reaction pathways are discussed. The major products of the title reaction are ethyl formate and formaldehyde, which is in accordance with experimental detection. The rate constants of the primary reactions over the temperature of 250-400K and the pressure range of 100-2000Torr are computed by employing MESMER program. At 298K and 760Torr, OH-addition channels are predominate and the total rate constant is ktot=4.53×10(-11)cm(3)molecule(-1)s(-1). The Arrhenius equation is obtained as ktot=6.27×10(-12)exp(611.5/T), according to the rate constants given at different temperatures. Finally, the atmospheric half life of EVE with respect to OH is estimated to be 2.13h. PMID:24997901

  7. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT....108 Ethyl ether. (a) Odor. Characteristic odor. (b) Specific gravity at 15.56 °/15.56 °C. Not...

  8. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  9. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  10. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  11. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  12. Highly efficient palladium-catalyzed hydrostannation of ethyl ethynyl ether

    PubMed Central

    Andrews, Ian P.; Kwon, Ohyun

    2008-01-01

    The palladium-catalyzed hydrostannation of acetylenes is widely exploited in organic synthesis as a means of forming vinyl stannanes for use in palladium-catalyzed cross-coupling reactions. Application of this methodology to ethyl ethynyl ether results in an enol ether that is challenging to isolate from the crude reaction mixture because of incompatibility with typical silica gel chromatography. Reported here is a highly efficient procedure for the palladium-catalyzed hydrostannation of ethyl ethynyl ether using 0.1% palladium(0) catalyst and 1.0 equiv of tributyltin hydride. The product obtained is a mixture of regioisomers that can be carried forward with exclusive reaction of the β-isomer. This method is highly reproducible; relative to previously reported procedures, it is more economical and involves a more facile purification procedure. PMID:20011027

  13. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Ethyl ether. 151.50-42 Section 151.50-42 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-42 Ethyl ether. (a)(1) Gravity...

  14. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Vinyl chloride-lauryl vinyl ether copolymers. 177.1970 Section 177.1970 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single...

  15. Cis-METHYL Vinyl Ether: the Rotational Spectrum up to 600 GHz

    NASA Astrophysics Data System (ADS)

    Kolesniková, Lucie; Daly, Adam M.; Alonso, José L.

    2014-06-01

    Astronomical observation of dimethyl ether, methyl ethyl ether places the methyl vinyl ether among the species of potential interstellar relevance. The millimeter and submillimeter-wave transitions pertaining to the vibrational ground state and the first excited states of the methoxy, ν24, and methyl, ν23, torsional modes and the in-plane bending mode, ν16, of the cis-methyl vinyl ether have been measured and analyzed in the frequency region from 50 to 600 GHz. A significant Fermi-type and Coriolis interactions between the v24=1 and v23=1 states have been observed and the rotational spectra were analyzed using an effective two-state Hamiltonian explicitly involving corresponding coupling operators. A sets of spectroscopic constants for the ground state as well as for all three excited states reproducing the observed spectrum within the experimental uncertainty provide sufficiently precise information for the astronomical search for methyl vinyl ether. Z. Peeters, S. D. Rodgers, S. B. Charnley, L. Schriver-Mazzuoli, A. Schriver, J. V. Keane, and P. Ehrenfreund, Astron. & Astrophys. 2006, 445, 197. G. W. Fuchs, U. Fuchs, T. F. Giesen, F. Wyrowski, Astron. & Astrophys. 2005, 444, 521. B. E. Turner, A. J. Apponi, Astrophys. J. Lett. 2001, 561, 207.

  16. Polymerization in the liquid crystalline state of vinyl ether monomers

    SciTech Connect

    Andersson, H.; Jonsson, H.; Gedde, U.W.; Hult, A.

    1993-12-31

    Liquid crystalline phenylbenzoate vinyl ether was polymerized cationically in both anisotropic and isotropic monomeric melts, using photochemical initiation by onium salts. High molecular mass polymers with a narrow molecular mass distribution (around 2) were produced by cationic polymerization at high temperatures ({<=}{degrees}C). The initial state of the monomer, nematic or isotropic, did not affect neither molecular mass, molecular mass distribution, nor polymerization rate. {sup 13}C-NMR studies show that the polymer formed is atactic. Ordered 30-50 {mu}m films were produced by polymerization of mesogenic vinyl ether monomers oriented in the nematic and smectic phase.

  17. Semi-empirical method for calculating the activation energies of the unimolecular thermal decomposition of vinyl ethers

    NASA Astrophysics Data System (ADS)

    Sargsyan, G. N.; Shakhrokh, B.; Harutyunyan, A. B.

    2015-02-01

    A semi-empirical method is proposed for calculating the activation energy of the unimolecular decomposition of complex compounds using the example of vinyl (ethyl, propyl, and butyl) ethers. The method is based on the concept of the formation of intramolecular hydrogen bonds and the possibility of calculating the energy of deformation of ether molecules upon activation, resulting in the potential surface of the transition state undergoing distortion and the transfer of a hydrogen atom from an alkyl group to a vinyl group. The energy of deformation is calculated using the Mathcad 2001i and MM2 computer programs.

  18. Vinyl ethers containing an epoxy group. XVI. Reaction of glycidol vinyloxyethyl ether with acetals

    SciTech Connect

    Nedolya, N.A.; Khil'ko, M.Ya.; Trofimov, B.A.; Sigalov, M.V.

    1988-10-10

    In order to obtain branched acetals with epoxide groups (prospective monomers and intermediates) the authors investigated the reaction of acetaldehyde diethyl and di(1,1,3-trihydrotetrafluoropropyl) acetals with glycidol vinyloxyethyl ether. The addition of acetals to vinyl epoxy ethers was realized, and the first representative of compounds of this type, i.e., 9-glycidyloxy-6-ethoxy-4-methyl-3,7-dioxanonane, was obtained. It was also impossible to add a fluoroacetal to butyl vinyl ether (0.08-1.00 wt. % of catalyst CF/sub 3/COOH, BF/sub 3//times/ OEt/sub 2/, 20-80/degree/C, 0.5-3 h).

  19. Photoinitiated cationic polymerization with multifunctional vinyl ether monomers

    SciTech Connect

    Cribello, J.V.; Lee, J.L.; Conlon, D.A.

    1983-01-01

    Until recently, multifunctional vinyl ether monomers have not been employed in UV curing applications. The recent discovery of diaryliodonium and triarylsulfonium salts as new classes of photoinitiators for cationic polylmerization has made it possible to formulate highly photosensitive UV curable coatings based on these monomers. The syntheses of these monomers and their reactivity as a function of their structure is reviewed and evaluated.

  20. Vibrational and VCD spectra of poly(menthyl vinyl ether)

    NASA Astrophysics Data System (ADS)

    McCann, J. L.; Bour, P.; Wieser, H.

    1998-06-01

    The detailed assignments are reported for the vibrational and VCD spectra of (1S,2R,5S)-(+)-menthol. Energy minimized geometries, harmonic force fields, and atomic polar tensors were calculated at the Becke3LYP/6-31G** level, and atomic axial tensors with the vibronic coupling theory at the HF/6-31G level. The spectra consist of contributions mainly from two isomers (70%) distinguished only by conformation of the OH group. An attempt was made to simulate the absorption and VCD spectra of poly(methyl vinyl ether) using a component approach and invoking the excitation scheme with promising though not conclusive results at this stage.

  1. Ambient gold-catalyzed O-vinylation of cyclic 1,3-diketone: A vinyl ether synthesis

    PubMed Central

    Xi, Yumeng; Dong, Boliang

    2013-01-01

    Summary Gold-catalyzed O-vinylation of cyclic 1,3-diketones has been achieved for the first time, which provides direct access to various vinyl ethers. A catalytic amount of copper triflate was identified as the significant additive in promoting this transformation. Both aromatic and aliphatic alkynes are suitable substrates with good to excellent yields. PMID:24367417

  2. Palladium-Catalyzed Selective α-Alkenylation of Pyridylmethyl Ethers with Vinyl Bromides.

    PubMed

    Yang, Xiaodong; Kim, Byeong-Seon; Li, Minyan; Walsh, Patrick J

    2016-05-20

    An efficient palladium-catalyzed α-alkenylation of pyridylmethyl ethers with vinyl bromides is presented. A Pd/NIXANTPHOS-based catalyst system enables a mild and chemoselective coupling between a variety of pyridylmethyl ethers and vinyl bromides in good to excellent yields. Under the mild conditions, β,γ-unsaturated products are obtained without isomerization or Heck byproducts observed. PMID:27160421

  3. Dual Behavior of Iodine Species in Condensation of Anilines and Vinyl Ethers Affording 2-Methylquinolines.

    PubMed

    Le, Song Thi; Yasuoka, Chisa; Asahara, Haruyasu; Nishiwaki, Nagatoshi

    2016-01-01

    A metal-free, mild and efficient method for the synthesis of 2-methylquinolines was successfully developed by condensation of anilines with vinyl ethers in the presence of catalytic amount of iodine. Modification of both pyridine and benzene moieties was easily achieved by changing only the vinyl ether and aniline. In this reaction, the iodine species was revealed to show dual behavior; molecular iodine serves as an oxidant, while its reduced form, hydrogen iodide, activates the vinyl ether. The redox reaction between these iodine species enables the use of a catalytic amount of iodine in this synthetic method. PMID:27347919

  4. Iridium-Catalyzed Branch-Selective Hydroarylation of Vinyl Ethers via C-H Bond Activation.

    PubMed

    Ebe, Yusuke; Nishimura, Takahiro

    2015-05-13

    Iridium-catalyzed hydroarylation of vinyl ethers via a directed C-H bond activation of aromatic compounds gave high yields of the corresponding addition products with high branch selectivity. PMID:25928127

  5. Reactions of perfluoro-1-alkylcycloalkenes with alcohols and properties of vinyl ethers formed

    SciTech Connect

    Snegirev, V.F.; Makarov, K.N.

    1986-12-10

    Perfluoro-1-alkylcycloalkenes react with alcohols to form products of vinyl and allyl substitution. Alkyl perfluorocycloakenyl ethers readily alkylate the fluoride ion and triethylamine, and by the action of SbF/sub 5/ convert into ..cap alpha.., ..beta..-unsaturated perfluoro ketones. When allyl perfluorocycloalkenyl ethers are heated, they isomerize into the corresponding ..cap alpha..-allylperfluorocycloalkanones.

  6. Polymer containing pendant vinyl ether groups useful in enhanced oil recovery using

    SciTech Connect

    Irani, C.A.; Harris, T.V.; Aetzer, W.R.

    1990-08-07

    This patent describes an improvement in a method for recovering oil from an underground oil-bearing earth formation penetrated by an injection well and a producing well, in which method carbon dioxide is injected into the formation to displace oil towards the producing well from which oil is produced to the surface. It comprises: injecting into the formation carbon dioxide, the viscosity of which is increased at least three-fold by the presence of a sufficient amount of polymer containing pendant vinyl ether groups and a sufficient amount of a cosolvent to form a solution of the polymer in the carbon dioxide, wherein the minimum solubility parameter of the polymer is reduced to 6.85(cal/cc)1/1/2 or less by control of the number of pendant vinyl ether groups and by the selection of the vinyl ether groups.

  7. Searching for trans ethyl methyl ether in Orion KL⋆

    NASA Astrophysics Data System (ADS)

    Tercero, B.; Cernicharo, J.; López, A.; Brouillet, N.; Kolesniková, L.; Motiyenko, R. A.; Margulès, L.; Alonso, J. L.; Guillemin, J.-C.

    2015-10-01

    We report on the tentative detection of trans ethyl methyl ether (tEME), t-CH3CH2OCH3, through the identification of a large number of rotational lines from each one of the spin states of the molecule towards Orion KL. We also search for gauche-trans-n-propanol, Gt-n-CH3CH2CH2OH, an isomer of tEME in the same source. We have identified lines of both species in the IRAM 30 m line survey and in the ALMA Science Verification data. We have obtained ALMA maps to establish the spatial distribution of these species. Whereas tEME mainly arises from the compact ridge component of Orion, Gt-n-propanol appears at the emission peak of ethanol (south hot core). The derived column densities of these species at the location of their emission peaks are ≤(4.0 ± 0.8) × 1015 cm-2 and ≤(1.0 ± 0.2) × 1015 cm-2 for tEME and Gt-n-propanol, respectively. The rotational temperature is ~100 K for both molecules. We also provide maps of CH3OCOH, CH3CH2OCOH, CH3OCH3, CH3OH, and CH3CH2OH to compare the distribution of these organic saturated O-bearing species containing methyl and ethyl groups in this region. Abundance ratios of related species and upper limits to the abundances of non-detected ethers are provided. We derive an abundance ratio N(CH3OCH3)/N(tEME) ≥ 150 in the compact ridge of Orion. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2011.0.00009.SV. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan) with NRC (Canada), NSC, and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. This work was also based on observations carried out with the IRAM 30-m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).Appendix A is available in electronic form at http://www.aanda.org

  8. Preparation of ordered and crosslinked films from liquid crystalline vinyl ether monomers

    SciTech Connect

    Andersson, H.; Sahlen, F.; Gedde, U.W.; Hult, A.

    1993-12-31

    Highly ordered densely crosslinked liquid crystalline poly(vinyl ether) films have been prepared by in-situ photopolymerization of oriented bifunctional mesogenic vinyl ether monomers. Orientation was achieved either by a simple surface treatment, using an unidirectionally rubbed polyimide film or by a magnetic field. Polymerization from various monomer phases resulted in LC polymer network films with different molecular organizations. The films were analyzed with small-angle X-ray scattering, polarized light microscopy and infrared-dichroism measurements. It was shown that films with nematic, smectic A and smectic B structures were obtained, the latter having a very high degree of orientation.

  9. Diarylrhodates as promising active catalysts for the arylation of vinyl ethers with Grignard reagents.

    PubMed

    Iwasaki, Takanori; Miyata, Yoshinori; Akimoto, Ryo; Fujii, Yuuki; Kuniyasu, Hitoshi; Kambe, Nobuaki

    2014-07-01

    Anionic diarylrhodium complexes, generated by reacting [RhCl(cod)]2 with 2 equiv of aryl Grignard reagents, were found to be effective active catalysts in cross-coupling reactions of vinyl ethers with aryl Grignard reagents, giving rise to the production of vinyl arenes. In this catalytic system, vinyl-O bonds were preferably cleaved over Ar-O or Ar-Br bonds. A lithium rhodate complex was isolated, and its crystal structure was determined by X-ray crystallography. PMID:24957673

  10. Synthesize and polymerization of novel photocurable vinyl ether monomers containing perfluorinated aromatic units

    NASA Astrophysics Data System (ADS)

    Li, Wei; Zou, Ying Quan

    2012-03-01

    A series of novel UV-curable vinyl ether monomers with perfluorinated aromatic units for photoresist had been designed and synthesized. Perfluorinated vinyl ether monomer I-1was prepared from the reactions of 2-vinyloxy ethanol and hexafluorobenzene in the presence of sodium hydride in DMF. And perfluorinated vinyl ether monomer I-2 was prepared from the reactions of I-1 and 2,2,2-trifluoroethanol in the presence of sodium carbonate in DMF. The photocrosslinked perfluorinated polymers obtained by PAG201 (a kind of cationic photo-initiator) initiating. When PAG201 was introduced into the monomers, the conversion of vinyl ether double bond increased sharply. The final conversion was close to 90%, and when the light intensity was 478μW/cm2, at 25 sec, the polymerization achieved maximum. Generally, the UV-curing performance of monomers with 3wt.% PAG201 concentration is superior to 2wt.% PAG201 concentration. And their physical and chemical properties satisfied the material requirements for photoresist or UV imaging materials.

  11. Maleate/vinyl ether UV-cured coatings: Effects of composition on curing and properties

    SciTech Connect

    Noren, G.K.

    1996-10-01

    The effect of the composition of the maleate polyester and the vinyl ether terminated compound on their UV-curing and properties has been investigated. Linear unsaturated polyester resins based on maleic anhydride and 1,5-pentane diol were synthesized. The molecular weight of the unsaturated polyesters was varied by changing the ratio of maleic anhydride to 1,5-pentane diol and the double bond equivalent weight was varied by replacing maleic anhydride with succinic anhydride. Coating formulations containing these unsaturated polyesters, triethylene glycol divinyl ether and a free radical photoinitiator were crosslinked in the presence of UV light. The coatings were very brittle, exhibiting tensile strengths in the range of 1.5-4.0 MPa and elongations of only 3-7%. Diethyl maleate and isobutyl vinyl ether were effective diluents for reducing viscosity but reduced the cure speed. A vinyl ether urethane oligomer was synthesized and enhanced the flexibility and toughness of the coatings when substituted for triethylene glycol divinyl ether.

  12. The millimeter and submillimeter wave spectrum of cis-methyl vinyl ether

    NASA Astrophysics Data System (ADS)

    Daly, A. M.; Kolesniková, L.; Mata, S.; Alonso, J. L.

    2014-12-01

    Among the species of potential interstellar relevance, methyl vinyl ether (CH3OCHdbnd CH2) is the simplest ether compound containing both alkyl and alkene functional groups. In order to facilitate its detection in the ISM, we have measured the millimeter and submillimeter wave spectra from 50 to 650 GHz. We present the analysis of pure rotational spectrum of the cis-methyl vinyl ether in the vibrational ground state and in the first excited states of in-plane bending mode (ν16) and methyl (ν23) and skeletal (ν24) torsional modes. Coriolis and Fermi type interactions between the v24 = 1 and v23 = 1 states have been explicitly treated using an effective two-state Hamiltonian.

  13. Oil compositions containing alkyl amine or alkyl mercaptan derivatives of copolymers of an alpha olefin or an alkyl vinyl ether

    SciTech Connect

    Le, H.T.

    1990-02-13

    This patent describes an oil composition. It comprises a major amount of an oil selected from a crude oil or fuel oil and a minor amount of an alkyl amine or alkyl mercaptan derivative of an alpha olefin or alkyl vinyl ether and an unsaturated alpha, beta-dicarboxylic compound copolymer having pour point depressant ;properties. The copolymer comprising the reaction product of an alpha olefin having from about 2 to about 30 carbon atoms or mixtures of alpha olefins having from about 2 to about 30 carbon atoms or an alkyl vinyl ether or mixture of alkyl vinyl ethers.

  14. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... determined by any suitable analytical procedure of generally accepted applicability. (ii) Inherent viscosity... D1243-79, “Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,” which...

  15. High absorbing resists based on trifluoromethacrylate-vinyl ether copolymers for EUV lithography

    NASA Astrophysics Data System (ADS)

    Christianson, Matthew D.; Meyer, Matthew M.; Ongayi, Owendi; Valeri, David; Wagner, Michael

    2013-03-01

    Highly sensitive EUV photoresists remain a critical challenge to enable high volume manufacturing with EUV lithography. Chemically amplified resists continue to provide the best sensitivity for EUV photoresists, but the high EUV transparency of most resists continues to waste a large percentage of EUV photons that pass through the resist film without photochemically generating acid. Highly fluorinated polymers have been proposed as more sensitive resist materials because fluorine increases EUV absorption of a material. Thus, methacrylate-like polymers with fluorinated backbones are an attractive possibility for new EUV resist materials. Trifluoromethacrylates are known to undergo free radical polymerization with electron rich comonomers such as vinyl ethers. The resulting polymers have backbone trifluoromethyl groups that enhance the absorption of EUV photons while retaining the potential for solubility change by acid-catalyzed tertiary ester deprotection similar to methacrylate-based chemically amplified resists. Interestingly, copolymerizations of trifluoromethacrylates and vinyl ethers are not particularly sensitive to traditional experimental parameters that influence polymer molecular weight. Instead, we have found that the structure of the vinyl ether comonomer has a profound impact on polymer molecular weight with acyclic vinyl ethers generating very high molecular weight polymers (Mw exceeding 100,000 g/mol) and cyclic vinyl ethers generating very low molecular weight polymers (Mw less than 10,000 g/mol) under similar conditions. Combination of cyclic and non-cyclic vinyl ethers in the monomer feed enables the synthesis of polymers at a desired molecular weight with a narrow polydispersity (PDI less than 2). Initial EUV contrast curves demonstrate potential for highly sensitive photoresists using these backbone-fluorinated polymers. A variety of polymers have been prepared to determine optimum compositions of leaving group, sensitizing, and etch resistant

  16. Condensation of perfluoroisobutylene with perfluorinated vinyl alkyl ethers

    SciTech Connect

    Postovoi, S.A.; Zeifman, Yu.V.; Knunyants, I.L.

    1986-12-10

    Condensation of perfluoroisobutylene with perfluorovinyl aklyl ethers with CsF catalysis takes place according to a scheme of concerted nucleophilic addition, with participation of the perfluoro-tert-butyl anion as nucleophile and perfluoroisobutylene as electrophile. In the presence of CO/sub 2/ the product of concerted perfluoroalkylcarboxylation forms.

  17. Infrared absorption and vibrational circular dichroism spectra of poly(vinyl ether) containing diastereomeric menthols as pendants

    NASA Astrophysics Data System (ADS)

    McCann, Jennifer L.; Rauk, Arvi; Wieser, Hal

    1997-06-01

    The absorption and vibrational circular dichroism (VCD) spectra in the 1700 to 830 cm -1 region are reported and qualitatively interpreted for poly(vinyl ether) with (+)-menthol (I), (+)-isomenthol (II) and (+)-neomenthol (III) as pendants.

  18. Kinetic study of the OH-initiated photo-oxidation of four unsaturated (allyl and vinyl) ethers under simulated atmospheric conditions

    NASA Astrophysics Data System (ADS)

    Peirone, Silvina A.; Aranguren Abrate, Juan P.; Taccone, Raúl A.; Cometto, Pablo M.; Lane, Silvia I.

    2011-09-01

    Using the relative rate technique, rate constants for the gas-phase reactions of hydroxyl radicals with n-propyl vinyl ether ( k1), 2-chloroethyl vinyl ether ( k2), allyl ether ( k3) and allyl ethyl ether ( k4) have been measured. Experiments were carried out at (298 ± 2) K and atmospheric pressure using N 2 and ultra pure air as bath gas. Using isoprene, 1-methyl-1-cyclohexene, 2-methyl-2-butene, 3-buten-1-ol and 2-methyl-2-propen-1-ol as reference compounds, the following rate constants were derived: k1 = (11.0 ± 0.4) × 10 -11, k2 = (9 ± 1) × 10 -11, k3 = (6.8 ± 0.7) × 10 -11 and k4 = (4.2 ± 0.7) × 10 -11, in units of cm 3 molecule -1 s -1. This is the first experimental detcermination of k2- k4. The rate constants obtained are compared with the previous literature data for corresponding alkenes reactions with OH and the observed reactivity trends are discussed. The atmospheric implications of the results are considered.

  19. Unique Curing Properties through Living Polymerization in Crosslinking Materials: Polyurethane Photopolymers from Vinyl Ether Building Blocks.

    PubMed

    Kirschbaum, Stefan; Landfester, Katharina; Taden, Andreas

    2015-05-01

    Photopolymers with unique curing capabilities were produced by combining living cationic polymerization with network formation and restricted polymer motion. A vinyl ether diol was synthesized as a functional building block and reacted with isophorone diisocyanate to form a highly functionalized vinyl ether polyurethane as a model system with high crosslinking ability. When using a cationic photoinitiator, fast polymerization is observed upon short UV irradiation. Curing proceeds in the absence of light and under ambient conditions without oxygen inhibition. Cationic active sites become trapped dormant species upon network-induced vitrification and surprisingly remain living for several days. The polymerization can be reactivated by additional UV irradiation and/or raised temperature. The curing behavior was studied in detail by using UV and FT-NIR coupled rheology and photo-DSC to simultaneously study spectroscopic and mechanical information, as well as thermal effects. PMID:25776255

  20. Macrocyclic polyenynes: a stereoselective route to vinyl-ether-containing skipped diene systems.

    PubMed

    Ronson, Thomas O; Voelkel, Martin H H; Taylor, Richard J K; Fairlamb, Ian J S

    2015-05-11

    The stereoselective synthesis of a challenging macrocyclic polyene scaffold, containing a sensitive vinyl ether motif, has been accomplished using O,C-dilithiation/selective C-alkylation, Pd-catalysed etherification and Wittig reactions as key steps. An end-game macrocyclisation strategy employed a regio- and stereoselective Stille cross-coupling using Pd(Br)(N-Succ)(AsPh3)2 (AsCat) as the precatalyst. PMID:25891970

  1. NMR study of products of the reaction of fulvenes with vinyl butyl ether

    SciTech Connect

    Yashtulov, N.A.; Dobrovinskii, L.A.; Cherkasov, A.N.; Kamyshina, L.G.; Livshits, R.M.

    1987-08-20

    The formation of copolymers with conjugated double bonds was proven by /sup 1/H and /sup 13/C NMR in cationic copolymerization of 6,6-disubstituted pentafulvenes with vinyl butyl ether. The composition and structure of the copolymers were determined. It was shown that it is possible to find the constants of copolymerization and distribution of the microblock nature in relation to the composition of the copolymers.

  2. Composites of vinyl polystyrylpyridine/bismaleimide-aliphatic ether copolymers

    NASA Technical Reports Server (NTRS)

    Heimbuch, Alvin H.; Rosser, Robert W.; Hsu, Ming-Ta S.

    1989-01-01

    An aliphatic ether bismaleimide was prepared and coreacted with a polyvinylstyrylpyridine (VPSP) oligomer. Studies showed that a controlled ratio of aliphatic to aromatic units in the polymer backbone improved both processibility and interlaminar shear properties for the carbon-fiber composite system. This modified resin was readily soluble in tetrahydrofuran, allowing for better fiber impregnation and thus enhancing adhesive properties and reproducibility. DSC studies have shown a lower cure temperature for the copolymer than for the neat aliphatic bismaleimide, and a glass transition temperature of 260 C, which is more than adequate for most applications. Limited measurements indicated an improvement in toughness (impact resistance).

  3. Radical Reactions of Alkyl 2-Bromo-2,2-difluoroacetates with Vinyl Ethers: "Omitted" Examples and Application for the Synthesis of 3,3-Difluoro-GABA.

    PubMed

    Kondratov, Ivan S; Bugera, Maksym Ya; Tolmachova, Nataliya A; Posternak, Ganna G; Daniliuc, Constantin G; Haufe, Günter

    2015-12-18

    Addition reactions of perfluoroalkyl radicals to ordinary or polyfluorinated alkenes have been frequently used to synthesize perfluoroalkylated organic compounds. Here ethyl/methyl 2-bromo-2,2-difluoroacetate, diethyl (bromodifluoromethyl)phosphonate, [(bromodifluoromethyl)sulfonyl]benzene, and ethyl 2-bromo-2-fluoroacetate were involved in Na2S2O4-mediated radical additions to vinyl ethers in the presence of alcohols to give difluoro or monofluoroacetyl-substituted acetals or corresponding difluoromethylphosphonate- and (difluoromethylphenyl)sulfonyl-substituted alkyl acetals. This methodology has also been applied as a key step in the synthesis of hitherto unknown 3,3-difluoro-GABA, completing the series of isomeric difluoro GABAs. Comparison of the pKa values of 3-fluoro- and 3,3-difluoro-GABA with that of the fluorine free parent compound showed that introduction of each fluorine lead to acidification of both the amino and the carboxyl functions by approximately one unit. PMID:26550962

  4. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (Interagency Science Consultation Draft)

    EPA Science Inventory

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent ...

  5. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (Public Comment Draft)

    EPA Science Inventory

    In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to e...

  6. IRIS Toxicological Review and Summary Documents for Tertiary Amyl Ethyl Ether (Taee)

    EPA Science Inventory

    This is EPA's first assessment of the noncancer health effects and carcinogenic potential of tertiary amyl ethyl ether (TAEE). The IRIS program is preparing an assessment that will incorporate health effects information available for TAEE, and current risk assessment methods. T...

  7. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (External Review Draft, 2009)

    EPA Science Inventory

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of ethyl tertiary butyl ether (ETBE) that when finalized will appear on the Integrated Risk Information System (IRIS) database.

  8. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (External Review Draft)

    EPA Science Inventory

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of ethyl tertiary butyl ether (ETBE) that when finalized will appear on the Integrated Risk Information System (IRIS) database.

  9. Vinyl carbamate epoxide, a major strong electrophilic, mutagenic and carcinogenic metabolite of vinyl carbamate and ethyl carbamate (urethane).

    PubMed

    Park, K K; Liem, A; Stewart, B C; Miller, J A

    1993-03-01

    Vinyl carbamate epoxide (VCO) was found to possess strong electrophilic, mutagenic and carcinogenic activities. It reacted with water at 37 degrees C and pH 7.4 (phosphate buffer) to form glycolaldehyde and several related reducing compounds; none of these products were mutagenic for Salmonella typhimurium TA1535. Under these conditions VCO had a half-life (determined chemically and mutagenically) of approximately 10.5 min. This half-life was progressively lowered by increasing concentrations of chloride ion (liver, serum and isotonic levels). This ion reacted with VCO to form chloroacetaldehyde. VCO also reacted with other nucleophiles such as glutathione, DNA and its constituent guanine and adenine bases. The purine adducts formed by VCO in DNA in vitro and in vivo were released by weak acid treatment and consisted of 7-(2'-oxoethyl)guanine and N2,3-ethenoguanine as major products with 1,N6-ethenoadenine as a minor product. VCO was a strong direct mutagen in Salmonella typhimurium TA1535 and TA100 but was only weakly active in the TA98 mutant. VCO was a stronger initiator of carcinogenesis in the skin of CD-1 mice and in the liver of infant male B6C3F1 mice than its metabolic precursors vinyl carbamate (VC) and ethyl carbamate (EC). Unlike VC and EC, VCO was a strong complete carcinogen in the skin of CD-1 mice and induced papillomas and carcinomas following repetitive administration of sub-ulcerogenic doses. VCO also exhibited some carcinogenic activity in the lungs of mice and in the s.c. and mammary tissue of female Sprague-Dawley rats. These data and those from other recent studies support the conclusion that VCO is a major strong electrophilic, mutagenic and carcinogenic metabolite of EC and VC in the mouse. PMID:8453720

  10. 40 CFR 721.5500 - 7-Oxabicyclo[4.1.0]heptane, 3-ethenyl, homopolymer, ether with 2-ethyl-2-(hydroxymethyl)-1,3-pro...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., homopolymer, ether with 2-ethyl-2-(hydroxymethyl)-1,3-pro-pane-diol (3:1), epoxidized. 721.5500 Section 721...-Oxabicyclo heptane, 3-ethenyl, homopolymer, ether with 2-ethyl-2-(hydroxymethyl)-1,3-pro-pane-diol (3:1... 7-oxabicyclo heptane, 3-ethenyl, homopolymer, ether with 2-ethyl-2(hydroxymethyl)-1,3-propanediol...

  11. Photoinitiated polymerization of new hybrid monomer containing vinyl ether and (methyl) acryloyl groups

    NASA Astrophysics Data System (ADS)

    Diao, Cuimei; Zou, Yingquan

    2011-04-01

    The photopolymerization kinetics of 4-(vinyloxy)butyl methacrylate containing cationic and free radical polymerizable vinyl groups was studied by real-time Fourier transform infrared spectra (RT-FTIR) .The cationic polymerizable vinyl ether moieties(Vc) of the hybrid monomer in solution polymerized rapidly by exposure to UV light in presence of a cationic photoinitiator such as an iodonium salt or suflonium salt .High conversions, of 90%, were obtained for most of the systems investigated. The efficiency of the cationic photoinitiators in initiating the polymerization of the vinyl ether moieties (Vc) of the hybrid monomer was in the order: suflonium salt > iodonium salt . The free radical polymerizable methacrylate groups (Vr) of the hybrid monomer in solution polymerized by exposure to UV light in presence of a radical photoinitiator such as 2,4,6-trimethyl benzoyl diphenylphoshine oxide (TPO), 2-isopropyl thioxanthone (ITX) , Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Irgaure 819), 2-Methyl-4'-(methylthio)-2-morpholinopropiophenone (Irgaure 907). Among the photoinitiators , the best effect in initiating the polymerization of methacrylate groups (Vr) of the hybrid monomer is initiator Irgaure 907.

  12. Synthesis and biological evaluation of vinyl ether-containing azole derivatives as inhibitors of Trichophyton rubrum.

    PubMed

    Wang, Lulu; Yang, Wenge; Wang, Kai; Zhu, Jing; Shen, Fei; Hu, Yonghong

    2012-07-15

    In an attempt to search for many target compounds with excellent activities, a series of vinyl ether-containing azole derivatives were designed, synthesized, and evaluated as antifungal agents. Results of preliminary antifungal tests against Trichophyton rubrum in vitro indicated that most of the synthesized compounds showed excellent activities. In comparison with fluconazole, itraconazole, voriconazole, omoconazole and amphotericin B, several compounds (such as 7d, 7g and 7h) exhibited more potent inhibitory activities, suggesting that they were promising leads for the development of novel antifungal agents. PMID:22683344

  13. Ac conduction in conducting poly pyrrole-poly vinyl methyl ether polymer composite materials

    SciTech Connect

    Saha, S.K.; Mandal, T.K.; Mandal, B.M.; Chakravorty, D.

    1997-03-01

    Composite materials containing conducting polypyrrole and insulating poly (vinyl methyl ether) (PVME) have been synthesized by oxidative polymerization of pyrrole in ethanol using FeCl{sub 3} oxidant in the presence of PVME. The ac conductivity measurements have been carried out in the frequency range of 100 Hz to 10 MHz and in the temperature range of 110 to 350 K. The frequency dependent conductivity has been explained on the basis of a small polaron tunnelling mechanism. {copyright} {ital 1997 American Institute of Physics.}

  14. Mechanism of iridium-catalysed branched-selective hydroarylation of vinyl ethers: a computational study.

    PubMed

    Zhang, Mei; Huang, Genping

    2016-02-16

    The iridium-catalysed branched-selective hydroarylation of vinyl ethers represents a rare example of the branched-selective hydroarylation involving the non-styrene-type alkenes. Herein, we report our DFT calculations on the mechanism of this reaction. The results show that after C-H oxidative addition, instead of the widely accepted Chalk-Harrod type mechanism, the branched-selective hydroarylation may proceed through an unconventional modified Chalk-Harrod type mechanism, involving the migratory insertion into the Ir-C bond and C-H reductive elimination. Both steric and electronic effects of the alkoxy group were found to account for the complete branched selectivity. PMID:26804666

  15. Ether complexes of tungsten with two different binding modes: An O-bound ether and an {eta}{sup 2}-(C=C) vinyl ether. Evidence for C-H...O hydrogen bonding of vinylic C-H groups

    SciTech Connect

    Song, J.S.; Szalda, D.J.; Bullock, R.M.

    1996-11-13

    The reaction of PhCH(OCH{sup 3}){sup 2} with Cp(CO){sup 3}WH and HOTf gives [Cp(CO){sup 3}W(PhCH{sup 2}OCH{sup 3})]{sup +}OTf{sup -}. The structure of this benzyl methyl ether complex was determined by single crystal X-ray diffraction and was shown to have the ether bonded to tungsten through the oxygen. This compound was isolated as a kinetic product of the reaction; it decomposes in solution by releasing free PhCH{sup 2}OCH{sup 3} and forming Cp(CO){sup 3}WOTf. An analog with the BAr`{sup 4}{sup -} counterion [Ar` = 3, 5-bis(trifluoromethyl)phenyl] is more stable. The reaction of the vinyl acetal CH{sup 2}=CHCH(OEt){sup 2} with Cp(CO){sup 3}WH and HOTf produces [Cp(CO){sup 3}W({eta}{sup 2}-EtOCH=CHCH{sup 3})]{sup +} OTf{sup -}, in which the ether is bonded to tungsten through the C=C bond of the vinyl ether. The crystal structure of this compound shows that the W-C(OEt) distance (2.69(3) A) is significantly longer than the W-C(CH{sup 3}) distance (2.37(3) A). There are weak C-H...O hydrogen bonds between both vinyl CH`s and oxygens of the triflate counterions. Evidence is presented that some of these weak hydrogen bonds are maintained in CD{sup 2}Cl{sup 2} solution but not in CD{sup 3}CN. 44 refs., 4 figs., 3 tabs.

  16. Microwave Spectroscopy of Trans-Ethyl Methyl Ether in the Torsionally Excited State 3

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kaori; Murata, Keigo; Tsunekawa, Shozo; Ohashi, Nobukimi

    2010-06-01

    The trans-ethyl methyl ether molecule (CH_3CH_2OCH_3) has two methyl group internal rotors which are equivalent to the two vibrational motions, ν28 and ν29. There is another low-lying torsional motion which is a skeltal torsion (ν30) and does not cause splitting. The microwave spectra of the trans-ethyl methyl ether molecule in the ν28 = 1, ν29 = 1, and ν30 = 1 have been studied and interactions between these states were discussed. In this paper we report results on the ν30 = 2, and 3 state. The analysis based on Hougen's tunneling matrix formulation considering two methyl groups are used. We try to interpret tunneling parameters obtained in the present analysis quantitatively from the viewpoint of torsion-torsion interaction.

  17. Complexation between poly(maleic acid/octyl vinyl ether) and poly(vinyl caprolactam) in aqueous solution and at the alumina/water interface.

    PubMed

    Qiu, Q; Somasundaran, P

    2002-09-01

    Solution and interfacial properties of binary polymer mixtures of poly(maleic acid/octyl vinyl ether) (PMAOVE) and poly(vinyl caprolactam) (PVCAP) have been studied for the alumina/water system. To test the hydrophobic effect, mixtures of poly(maleic acid/methyl vinyl ether) (PMAMVE) and PVCAP are also investigated and compared to the behavior of PMAOVE/PVCAP. At low pH, both polymer mixtures become turbid upon mixing. The turbidity increases at low mixing ratios of PVCAP to the vinyl ether component, reaches a maximum, and then decreases at higher mixing ratios. Upon shifting the pH to the alkaline range, i.e., pH 7.5 and above, the turbid solution becomes clear for both the polymer mixtures. Cloud point measurements indicate the absence of complexation of PVCAP with PMAMVE under the alkaline conditions, but strong interaction with PMAOVE. This is attributed to the different forces involved in the complexation among the polymers: H bonding for PVCAP/PMAMVE and both H bonding and hydrophobic effects for PVCAP/PMAOVE. At the alumina/water interface, the normally nonadsorbing PVCAP is triggered to adsorb by PMAOVE, attributed to the hydrophobic complexation between the two. However, the adsorption of PVCAP shows a maximum as a function of the concentration of PMAOVE. At concentrations of PMAOVE above the onset of its own plateau adsorption, the amount of PVCAP triggered to adsorb is reduced possibly due to the polymer complex formation in solution. PMID:16290852

  18. Influence of Alkoxy Groups on the Photoinduced Dynamics of Organic Molecules Exemplified on Alkyl Vinyl Ethers.

    PubMed

    Schalk, O; Stenrup, M; Geng, T; Lindh, R; Thomas, R D; Feifel, R; Hansson, T

    2015-11-12

    A series of different alkyl vinyl ethers is investigated to decipher the possible reaction channels upon photoexcitation to the π3s-Rydberg and the ππ*-valence state at 200 nm using time-resolved photoelectron spectroscopy and on-the-fly time-dependent density functional theory dynamics simulations. The results indicate two possible relaxation pathways: (1) a radiationless decay through the ππ*-state back to the ground state via torsion of the C═C double bond, in accordance with the dynamics found in ethylene; and (2) a fast dissociation of the C-O bond between the alkyl and the vinoxy group in the πσ*-state. The latter state can be accessed only after excitation to the π3s-Rydberg state (quantum yield of ∼50% according to the dynamics simulations). Additionally, the excited state barrier leading to formation of a vinyl radical was found to be too high to be crossed. These results indicate that the dynamics of ethers crucially depend on the excitation wavelength and that the πσ*-state constitutes an important competitive reaction channel that leads to dissociation of the molecules. PMID:26490385

  19. 40 CFR 721.7700 - Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (3:1). 721.7700 Section 721.7700... Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3... substance identified as poly(oxy-1,2-ethanediyl),α-hydro-ω-(oxiranylmethoxy)-, ether with...

  20. 40 CFR 721.7700 - Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (3:1). 721.7700 Section 721.7700... Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3... substance identified as poly(oxy-1,2-ethanediyl),α-hydro-ω-(oxiranylmethoxy)-, ether with...

  1. Oxazolidines. 2. Synthesis of 2-methyloxazolidines by cyclization of vinyl ethers of 1,2-amino alcohols

    SciTech Connect

    Kukharev, B.F.; Stankevich, V.K.; Klimenko, G.R.; Terent'eva, V.P.; Kukhareva, V.A.

    1986-10-01

    A study has been made of the catalytic activity of a number of proton acids and Lewis acids, amongst which mercury salts were particularly active, in the cyclization of N-phenylethanolamine vinyl ether to 2-methyl-3-phenyloxazolidine. A method for the preparative synthesis of 2-methyloxazolidines has been developed.

  2. Investigation of quantitative structure-reactivity relationships in the aliphatic Claisen rearrangement of bis-vinyl ethers reveals a dipolar, dissociative mechanism.

    PubMed

    O'Rourke, Natasha F; Wulff, Jeremy E

    2014-02-28

    Kinetic investigations of substituent effects in the thermal rearrangement of bis-vinyl ether substrates are reported. Findings indicate that the influence of the various substituent patterns on the rate of rearrangement in these compounds differs from that documented in the literature for the analogous [3,3]-sigmatropic rearrangement of allyl vinyl ethers. In addition, the thermochemical data collected suggests the existence of a dissociative transition state with significant dipolar character. These findings provide a unique contribution to the already extensive body of literature dedicated to mechanistic investigation of the Claisen rearrangement of aliphatic allyl vinyl ethers. PMID:24424964

  3. A Mild Synthesis of New Aryl Vinyl Ethers and Diethyl 1-[(Alkyl)(cyano)methyl]vinylphosphonates via the Substitution of a 2,3-Difunctional Allyl Bromide

    PubMed Central

    Ben Kraïem, Jihène; Arfaoui, Aïcha; Amri, Hassen

    2014-01-01

    A novel class of aryl vinyl ethers 3 and diethyl 3-cyano-3-alkylprop-1-en-2-ylphosphonates 4 has been prepared, respectively, from coupling reaction of diethyl 1-(bromomethyl)-2-cyanovinylphosphonate 2 with phenols and Gilman reagents. PMID:24688373

  4. Influence of the brewing process on furfuryl ethyl ether formation during beer aging.

    PubMed

    Vanderhaegen, Bart; Neven, Hedwig; Verstrepen, Kevin J; Delvaux, Freddy R; Verachtert, Hubert; Derdelinckx, Guy

    2004-11-01

    In beer, the development of a solvent-like stale flavor is associated with the formation of furfuryl ethyl ether. The synthesis rate of this important flavor compound is proportional to the concentration of furfuryl alcohol in beer. This study shows that furfuryl alcohol in beer is mainly formed by Maillard reactions initiated during wort boiling and malt production. A mechanism for its formation from alpha-(1,4)-oligoglucans and amino acids in wort and beer is proposed. During wort boiling, a quadratic relationship was found between the wort extract concentration, on the one hand, and the increase of furfuryl alcohol and furfural, on the other. The reduction of furfural by yeast during fermentation further increases the furfuryl alcohol content. In pale beers, the furfuryl alcohol concentration is essentially determined by the thermal load on wort during brewing operations. In dark beers, a considerable fraction of furfuryl alcohol may, however, come from the dark malts used. These results lead to important practical conclusions concerning the control over furfuryl ethyl ether in beer. PMID:15506813

  5. 40 CFR 721.5500 - 7-Oxabicyclo[4.1.0]heptane, 3-ethenyl, homopolymer, ether with 2-ethyl-2-(hydroxymethyl)-1,3-pro...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 7-Oxabicyclo heptane, 3-ethenyl, homopolymer, ether with 2-ethyl-2-(hydroxymethyl)-1,3-pro-pane-diol (3:1), epoxidized. 721.5500 Section 721...-Oxabicyclo heptane, 3-ethenyl, homopolymer, ether with 2-ethyl-2-(hydroxymethyl)-1,3-pro-pane-diol...

  6. Oil compositions containing alkyl mercaptan derivatives of copolymers of an alpha olefin or an alkyl vinyl ether and an unsaturated alpha, beta-dicarboxylic compound

    SciTech Connect

    Le, H.T.

    1991-10-08

    This paper describes an oil composition. It comprises: a major amount of an oil selected from a mineral oil or synthetic oil and a manor amount of an alkyl mercaptan derivative of an alpha olefin or alkyl vinyl either and an unsaturated alpha, beta-dicarboxylic compound copolymer having pour point depressant properties, the copolymer comprising the reaction product of an alpha a olefin having from about 2 to about 30 carbon atoms or mixtures of alpha olefins having from about 2 to about 30 carbonates or an alkyl vinyl ether or mixture of alkyl vinyl ethers.

  7. Coupled torsional and bending motions in s-cis methyl vinyl ether

    NASA Astrophysics Data System (ADS)

    Meyer, Rolf; Ha, Tae-Kyu; Oldani, Markus; Caminati, Walther

    1987-02-01

    New microwave measurements on s-cis methyl vinyl ether and a study of the interactions among skeletal and methyl torsions and COC bending are reported. Using pulsed microwave Fourier transform spectroscopy, the small methyl torsional A-E splitting (0.16 MHz) in the vibrational ground state has been resolved for the first time. Large splittings are observed in the first excited states of skeletal torsion and COC bending. Ab initio results on the torsional coupling, allowing for structural relaxation, are reported and used to specify, in part, a flexible model for the torsional and bending motions. The spectroscopic properties of this three-dimensional model sytem, as estimated from the results for the one-dimensional and two-dimensional subsystems, explain the relevant experimental data. The gearing type torsional interaction predicted ab initio is confirmed by this treatment. The adjusted potential function as well as the structural relaxations upon torsion suggest repulsive interaction between the methyl hydrogen atoms and the methylenic hydrogen atom next to the methyl group.

  8. Tuning the Miscibility of Polystyrene / Poly(vinyl methyl ether) Blends with Electric Fields

    NASA Astrophysics Data System (ADS)

    Kriisa, Annika; Roth, Connie

    2014-03-01

    Application of electric fields seem experimentally simple, as they can be switched on and off instantly and effortlessly. Nevertheless the influence of electric fields on the phase separation temperature Ts in small molecules and polymeric mixtures is not yet well understood. Available theoretical calculations use thermodynamic arguments for adding an electrostatic free energy term to the total free energy of mixing and predict changes in Ts due to external electric fields that are much smaller than what most experimental results report. To date, neither theory or experiments have found a clear consensus on whether uniform electric fields enhance mixing or demixing. As only a few experimental results have been published over the past several decades with typically only small shifts in Ts, more experiments with unambiguously large shifts in Ts are needed to better understand this effect. Using a fluorescence technique we have developed for measuring the phase separation temperature Ts of polystyrene (PS) / poly(vinyl methyl ether) (PVME) blends [J. Polym. Sci., Part B 2012, 50, 250-256], we investigate the change in Ts due to the presence of electric fields. We show that electric fields strongly enhance mixing in PS/PVME polymer blends. For example, for a 50/50 PS/PVME blend composition, Ts is increased by over 10 K for electric fields of 18 kV/mm.

  9. Biodegradation of the gasoline oxygenates methyl tert-butyl ether, ethyl tert-butyl ether, and tert-amyl methyl ether by propane-oxidizing bacteria.

    PubMed Central

    Steffan, R J; McClay, K; Vainberg, S; Condee, C W; Zhang, D

    1997-01-01

    Several propane-oxidizing bacteria were tested for their ability to degrade gasoline oxygenates, including methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). Both a laboratory strain and natural isolates were able to degrade each compound after growth on propane. When propane-grown strain ENV425 was incubated with 20 mg of uniformly labeled [14C]MTBE per liter, the strain converted > 60% of the added MTBE to 14CO2 in < 30 h. The initial oxidation of MTBE and ETBE resulted in the production of nearly stoichiometric amounts of tert-butyl alcohol (TBA), while the initial oxidation of TAME resulted in the production of tert-amyl alcohol. The methoxy methyl group of MTBE was oxidized to formaldehyde and ultimately to CO2. TBA was further oxidized to 2-methyl-2-hydroxy-1-propanol and then 2-hydroxy isobutyric acid; however, neither of these degradation products was an effective growth substrate for the propane oxidizers. Analysis of cell extracts of ENV425 and experiments with enzyme inhibitors implicated a soluble P-450 enzyme in the oxidation of both MTBE and TBA. MTBE was oxidized to TBA by camphor-grown Pseudomonas putida CAM, which produces the well-characterized P-450cam, but not by Rhodococcus rhodochrous 116, which produces two P-450 enzymes. Rates of MTBE degradation by propane-oxidizing strains ranged from 3.9 to 9.2 nmol/min/mg of cell protein at 28 degrees C, whereas TBA was oxidized at a rate of only 1.8 to 2.4 nmol/min/mg of cell protein at the same temperature. PMID:9361407

  10. Structure of pyridine and quinoline vinyl ethers according to data from /sup 1/H and /sup 13/C NMR spectra and quantum-chemical calculations

    SciTech Connect

    Afonin, A.V.; Voronov, V.K.; Andriankov, M.A.; Danovich, D.K.

    1987-08-10

    A systematic investigation of the structure of the vinyl ethers of heterocyclic compounds has not been undertaken. The present work was devoted to investigation of the stereochemical and electronic structure of the vinyl ethers of pyridine and quinoline. The PMR spectra of the samples were recorded for 5% solutions in deuterochloroform on a Tesla BS-497 spectrometer at 100 MHz. The /sup 13/C NMR spectra were recorded on a Tesla BS-567A spectrometer at 25.1 MHz in deuterochloroform with the samples at concentrations of 30%. The internal standard was HMDS. The vinyl ethers of pyridine and quinoline exist preferentially in the nonplanar S-trans conformation. In the vinyl esters of pyridine and quinoline the p-..pi.. conjugation is concurrent in nature and depends on the position of the vinyloxy group in the heterocycle.

  11. Searching for trans ethyl methyl ether in Orion KL★,★★

    PubMed Central

    Tercero, B.; Cernicharo, J.; López, A.; Brouillet, N.; Kolesniková, L.; Motiyenko, R. A.; Margulès, L.; Alonso, J. L.; Guillemin, J.-C.

    2015-01-01

    We report on the tentative detection of trans ethyl methyl ether (tEME), t-CH3CH2OCH3, through the identification of a large number of rotational lines from each one of the spin states of the molecule towards Orion KL. We also search for gauche-trans-n-propanol, Gt-n-CH3CH2CH2OH, an isomer of tEME in the same source. We have identified lines of both species in the IRAM 30 m line survey and in the ALMA Science Verification data. We have obtained ALMA maps to establish the spatial distribution of these species. Whereas tEME mainly arises from the compact ridge component of Orion, Gt-n-propanol appears at the emission peak of ethanol (south hot core). The derived column densities of these species at the location of their emission peaks are ≤(4.0 ± 0.8) × 1015 cm−2 and ≤(1.0 ± 0.2)× 1015 cm−2 for tEME and Gt-n-propanol, respectively. The rotational temperature is ~100 K for both molecules. We also provide maps of CH3OCOH, CH3CH2OCOH, CH3OCH3, CH3OH, and CH3CH2OH to compare the distribution of these organic saturated O-bearing species containing methyl and ethyl groups in this region. Abundance ratios of related species and upper limits to the abundances of non-detected ethers are provided. We derive an abundance ratio N(CH3OCH3)/N(tEME) ≥ 150 in the compact ridge of Orion. PMID:26869726

  12. Microwave Spectroscopy of Trans-Ethyl Methyl Ether in the Ground State

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kaori; Sakai, Yusuke; Tsunekawa, Shozo; Miyamoto, Taihei; Fujitake, Masaharu; Ohashi, Nobukimi

    2013-06-01

    The trans-ethyl methyl ether molecule (CH_3CH_2OCH_3) has two inequivalent methyl group internal rotors which corresponds to the two vibrational motions, ν_{28} and ν_{29}. Due to these internal rotations, a rotational transition could be split into maximum five components. The skeletal torsion (ν_{30}) is another low-lying state (ν_{30}) that interacts with the ν_{28} and ν_{29} modes. The microwave spectra of the trans-ethyl methyl ether molecule in the ν_{28} = 1, ν_{29} = 1, and ν_{30} = 1, 2 and 3 have been extensively studied by using Hougen's tunneling matrix formalism. The microwave spectroscopy in the ground state was studied by several groups. The splitting due to the ν_{28} mode (C-CH_3 internal rotation) is small in the ground state and was not fully resolved in most of the previous studied rotational transitions. In this paper, we report the results of the pulsed nozzle-jet Fourier transform microwave spectroscopy so as to measure the fully resolved spectra. The submillmeter wave spectroscopy was also carried out. Our analysis including the previously reported transitions would be useful for astronomical observations. K. Kobayashi, T. Matsui, N. Mori, S. Tsunekawa, and N. Ohashi J. Mol. Spectrosc. {269}, 242 2011. K. Kobayashi, T. Matsui, S. Tsunekawa, and N. Ohashi J. Mol. Spectrosc. {255}, 164 2009. K. Kobayashi, T. Matsui, N. Mori, S. Tsunekawa, and N. Ohashi J. Mol. Spectrosc.{251}, 301 2008. K. Kobayashi, K. Murata, S. Tsunekawa, and N. Ohashi Int. Symposium on Mol. Spectrosc., 65th Meeting TH15 2010.} M. Hayashi, and K. Kuwada J. Mol. Structure {28}, 147 1975. M. Hayashi, and M. Adachi J. Mol. Structure {78}, 53 1982. S. Tsunekawa, Y. Kinai, Y. Kondo, H. Odashima, and K. Takagi Molecules {8}, 103 2003. U. Fuchs, G. Winnewisser, P. Groner, F. C. De Lucia, and E. Herbst Astrophys. J. Suppl. {144}, 277 2003.

  13. Electric fields enhance miscibility of polystyrene/poly(vinyl methyl ether) blends

    NASA Astrophysics Data System (ADS)

    Kriisa, Annika; Roth, Connie B.

    2014-10-01

    How the presence of electric fields alters the miscibility of mixtures has been studied since the 1960s with conflicting reports on both the magnitude and direction of the shift in the phase separation temperature Ts. Theoretical understanding of the phenomenon has been hampered by the lack of experimental data with unambiguously large shifts in Ts outside of experimental error. Here, we address these concerns by presenting data showing that uniform electric fields strongly enhance the miscibility of polystyrene (PS)/poly(vinyl methyl ether) (PVME) blends. Reliable shifts in Ts of up to 13.5 ± 1.4 K were measured for electric fields strengths of E = 1.7 × 107 V/m in a 50/50 PS/PVME mixture. By using a sensitive fluorescence method to measure Ts, the PS/PVME blend can be quenched back into the one phase region of the phase diagram when the domains are still small allowing the blend to be remixed such that Ts can be measured repeatedly on the same sample. In this manner, highly reproducible Ts values at non-zero and zero electric field can be ascertained on the same sample. Our results agree with the vast majority of existing experimental data on various mixtures finding that electric fields enhance miscibility, but are opposite to the one previous study on PS/PVME blends by Reich and Gordon [J. Polym. Sci.: Polym. Phys. Ed. 17, 371 (1979)] reporting that electric fields induce phase separation, a study which has been considered anomalous in the field.

  14. Quasielastic neutron scattering study of hydrogen motions in an aqueous poly(vinyl methyl ether) solution

    NASA Astrophysics Data System (ADS)

    Capponi, S.; Arbe, A.; Cerveny, S.; Busselez, R.; Frick, B.; Embs, J. P.; Colmenero, J.

    2011-05-01

    We present a quasielastic neutron scattering (QENS) investigation of the component dynamics in an aqueous Poly(vinyl methyl ether) (PVME) solution (30% water content in weight). In the glassy state, an important shift in the Boson peak of PVME is found upon hydration. At higher temperatures, the diffusive-like motions of the components take place with very different characteristic times, revealing a strong dynamic asymmetry that increases with decreasing T. For both components, we observe stretching of the scattering functions with respect to those in the bulk and non-Gaussian behavior in the whole momentum transfer range investigated. To explain these observations we invoke a distribution of mobilities for both components, probably originated from structural heterogeneities. The diffusive-like motion of PVME in solution takes place faster and apparently in a more continuous way than in bulk. We find that the T-dependence of the characteristic relaxation time of water changes at T ≲ 225 K, near the temperature where a crossover from a low temperature Arrhenius to a high temperature cooperative behavior has been observed by broadband dielectric spectroscopy (BDS) [S. Cerveny, J. Colmenero and A. Alegría, Macromolecules, 38, 7056 (2005), 10.1021/ma050811t]. This observation might be a signature of the onset of confined dynamics of water due to the freezing of the PVME dynamics, that has been selectively followed by these QENS experiments. On the other hand, revisiting the BDS results on this system we could identify an additional "fast" process that can be attributed to water motions coupled with PVME local relaxations that could strongly affect the QENS results. Both kinds of interpretations, confinement effects due to the increasing dynamic asymmetry and influence of localized motions, could provide alternative scenarios to the invoked "strong-to-fragile" transition.

  15. Gold-catalyzed annulations of 2-alkynyl benzaldehydes with vinyl ethers: synthesis of dihydronaphthalene, isochromene, and bicyclo[2.2.2]octane derivatives.

    PubMed

    Malhotra, Deepika; Liu, Le-Ping; Mashuta, Mark S; Hammond, G B

    2013-03-18

    With the suitable selection of a gold catalyst as well as the appropriate control of the reaction conditions, various new gold-catalyzed cyclizations of 2-alkynyl benzaldehyde with acyclic or cyclic vinyl ethers have been developed. Acetal-tethered dihydronaphthalene and isochromenes were obtained from the reactions of 2-alkynyl benzaldehydes with acyclic vinyl ethers under mild conditions. And, more interestingly, the gold-catalyzed reactions of 2-alkynyl benzaldehyde with a cyclic vinyl ether afforded the bicyclo[2.2.2]octane derivative involving two molecules of cyclic vinyl ethers. These products contain interesting substructures that have been found in many biologically active molecules and natural products. In addition, a gold-catalyzed homo-dimerization of 2-phenylethynyl benzaldehyde 1a was observed when the reaction was carried out in the absence of vinyl ether, affording a set of separable diastereomeric products. Plausible mechanisms for these transformations are discussed; a gold-containing benzopyrylium was regarded as the crucial intermediate by which a number of these new transformations took place. PMID:23362089

  16. Asymmetric synthesis of α,α-disubstituted amino acids by cycloaddition of (E)-ketonitrones with vinyl ethers.

    PubMed

    Zhang, Xiaofei; Cividino, Pascale; Poisson, Jean-François; Shpak-Kraievskyi, Pavlo; Laurent, Mathieu Y; Martel, Arnaud; Dujardin, Gilles; Py, Sandrine

    2014-04-01

    Original acyclic (E)-α,α-dialkylketonitrones bearing a chiral auxiliary on their nitrogen atom were synthesized and successfully employed for the asymmetric synthesis of α,α-disubstituted amino acids using regio- and stereocontrolled 1,3-dipolar cycloaddition reactions with vinyl ethers. N-Glycosyl chiral auxiliaries were found to provide excellent exo- and π-facial stereocontrol. The obtained enantiopure cycloadducts were selectively transformed into functional α,α-disubstituted amino acids and related β-peptides through the highly regioselective opening of an intermediate quaternary anhydride. PMID:24650145

  17. Vinyl ethers containing a cyclic carbonate group. I. Synthesis of 3-(/omega/-vinyloxyalkoxy)propylene 1,2-carbonates

    SciTech Connect

    Nedolya, N.A.; Tatarova, T.F.; Vyalykh, E.P.; Trofimov, B.A.

    1989-01-10

    In order to synthesize 3-(/omega/-vinyloxyalkoxy)propylene 1,2-carbonates the authors studied the reaction of /omega/-vinyloxyalkoxymethyloxiranes with carbon dioxide at 140-180/degree/C, catalyzed by a tertiary amine (triethylamine). The main results from this reaction are described. The effect of the reaction conditions (solvent, concentration of catalyst, ratio of reagents, state of aggregation of the carbon dioxide, process temperature and time) on the result were studied for the case of 2-vinyloxyethoxymethyloxirane. The reaction leads with high yields to functional vinyl ethers of a new type - 3-(/omega/-vinyloxyalkoxy)propylene 1,2-carbonates.

  18. Luteinizing hormone-releasing hormone targeted poly(methyl vinyl ether maleic acid) nanoparticles for doxorubicin delivery to MCF-7 breast cancer cells.

    PubMed

    Varshosaz, Jaleh; Jahanian-Najafabadi, Ali; Ghazzavi, Jila

    2016-08-01

    The purpose of this study was to design a targeted anti-cancer drug delivery system for breast cancer. Therefore, doxorubicin (DOX) loaded poly(methyl vinyl ether maleic acid) nanoparticles (NPs) were prepared by ionic cross-linking method using Zn(2+) ions. To optimise the effect of DOX/polymer ratio, Zn/polymer ratio, and stirrer rate a full factorial design was used and their effects on particle size, zeta potential, loading efficiency (LE, %), and release efficiency in 72 h (RE72, %) were studied. Targeted NPs were prepared by chemical coating of tiptorelin/polyallylamin conjugate on the surface of NPs by using 1-ethyl-3-(3-dimethylaminopropyl) carboiimid HCl as cross-linking agent. Conjugation efficiency was measured by Bradford assay. Conjugated triptorelin and targeted NPs were studied by Fourier-transform infrared spectroscopy (FTIR). The cytotoxicity of DOX loaded in targeted NPs and non-targeted ones were studied on MCF-7 cells which overexpress luteinizing hormone-releasing hormone (LHRH) receptors and SKOV3 cells as negative LHRH receptors using Thiazolyl blue tetrazolium bromide assay. The best results obtained from NPs prepared by DOX/polymer ratio of 5%, Zn/polymer ratio of 50%, and stirrer rate of 960 rpm. FTIR spectrum confirmed successful conjugation of triptorelin to NPs. The conjugation efficiency was about 70%. The targeted NPs showed significantly less IC50 for MCF-7 cells compared to free DOX and non-targeted NPs. PMID:27463791

  19. /sup 13/C-/sup 13/C spin-spin coupling constants in structural investigations. II. Conformational structure of vinyl ethers

    SciTech Connect

    Krivdin, L.B.; Shcherbakov, V.V.; Bzhezovskii, V.M.; Kalabin, G.A.

    1986-10-10

    The /sup 13/C-/sup 13/C spin-spin coupling constants between the carbon nuclei of the vinyl group were measured for a series of vinyl ethers. It was established that the unshared electron pairs of the oxygen atom can make a substantial stereospecific contribution to the direct /sup 13/C-/sup 13/C constants of the adjacent nuclei. The observed effect was used to establish the conformational structure of the compounds.

  20. Aerobic addition of secondary phosphine oxides to vinyl sulfides: a shortcut to 1-hydroxy-2-(organosulfanyl)ethyl(diorganyl)phosphine oxides

    PubMed Central

    Malysheva, Svetlana F; Artem’ev, Alexander V; Gusarova, Nina K; Belogorlova, Nataliya A; Albanov, Alexander I; Liu, C W

    2015-01-01

    Summary Secondary phosphine oxides react with vinyl sulfides (both alkyl- and aryl-substituted sulfides) under aerobic and solvent-free conditions (80 °C, air, 7–30 h) to afford 1-hydroxy-2-(organosulfanyl)ethyl(diorganyl)phosphine oxides in 70–93% yields. PMID:26664618

  1. Ethyl-tertiary-butyl-ether (ETBE) as an aviation fuel: Eleventh international symposium on alcohol fuels

    SciTech Connect

    Maben, G.D.; Shauck, M.E.; Zanin, M.G.

    1996-12-31

    This paper discusses the preliminary flight testing of an aircraft using neat burning ethyl-tertiary-butyl-ether (ETBE) as a fuel. No additional changes were made to the fuel delivery systems which had previously been modified to provide the higher fuel flow rates required to operate the engine on neat ethanol. Air-fuel ratios were manually adjusted with the mixture control. This system allows the pilot to adjust the mixture to compensate for changes in air density caused by altitude, pressure and temperature. The engine was instrumented to measure exhaust gas temperatures (EGT), cylinder head temperatures (CHT), and fuel flows, while the standard aircraft instruments were used to collect aircraft performance data. Baseline engine data for ETBE and Avgas are compared. Preliminary data indicates the technical and economic feasibility of using ETBE as an aviation fuel for the piston engine fleet. Furthermore, the energy density of ETBE qualifies it as a candidate for a turbine engine fuel of which 16.2 billion gallons are used in the US each year.

  2. The Absolute Rates of the Solution Phase Addition of Atomic Hydrogen to a Vinyl Ether and a Vinyl Ester. The Effect of Oxygen Substitution on Hydrogen Atom Reactivity with Olefins

    SciTech Connect

    Tanner, D. D.; Kandanarachchi, P.; Das, N. C.; Franz, James A.

    2003-04-08

    The reactions of vinyl butyl ether and vinyl butyrate with atomic hydrogen and deuterium lead to addition of atomic hydrogen to the terminal position of the olefins. This observation is consistent with the reactions carried out earlier with other olefins. Both the absolute rates of addition to vinylbutyl ether and vinyl butyrate in acetone and hexane were carried out at several temperatures. The relative rates are consistent with only modest stabilization of the transition state of the radical adduct by the ??-o substituent compared with hydrogen atom addition to 1-octene. The relative rates measured in acetone and hexane indicate no significant differential solvation of ground state relative to the transition structures of the hydrogen atom addition. The kinetics reveal that the early transition states of hydrogen atom addition exhibit little selectivity (vinyl ether versus simple olefin) in either abstraction of hydrogen ??- to the oxygen or by terminal addition to the olefinic ether, reflecting the modest influence of the increased enthalpy of reaction associated with resonance stabilization by the oxygen substituent at the developing radical site.

  3. Absolute Rates of the Solution-Phase Addition of Atomic Hydrogen to a Vinyl Ether and a Vinyl Ester: Effect of Oxygen Substitution on Hydrogen Atom Reactivity with Olefins

    SciTech Connect

    Tanner, D D.; Kandanarachchi, P; Das, N. C.; Franz, James A.

    2003-04-08

    The reactions of vinyl butyl ether and vinyl butyrate with atomic hydrogen and deuterium lead to addition at the terminal position of the olefins. This observation is consistent with the reactions carried out earlier with other olefins. Both of the absolute rates of addition to vinylbutyl ether and vinyl butyrate, in acetone and hexane, were measured at several temperatures. The relative rates are consistent with only modest stabilization of the transition state of the radical adduct by the R-O substituent compared with that of hydrogen atom addition to 1-octene. The relative rates measured in acetone and hexane indicate no significant differential solvation of the ground state relative to the transition structures of the hydrogen atom addition. The kinetics reveal that the early transition states for hydrogen atom addition exhibit little selectivity (vinyl ether versus simple olefin) in either the abstraction of hydrogen R to the oxygen or by terminal addition to the olefinic ether and reflects the modest influence of the increased enthalpy of reaction associated with resonance stabilization by the oxygen substituent at the developing radical site.

  4. Subchronic exposure to ethyl tertiary butyl ether resulting in genetic damage in Aldh2 knockout mice.

    PubMed

    Weng, Zuquan; Suda, Megumi; Ohtani, Katsumi; Mei, Nan; Kawamoto, Toshihiro; Nakajima, Tamie; Wang, Rui-Sheng

    2013-09-15

    Ethyl tertiary butyl ether (ETBE) is biofuel additive recently used in Japan and some other countries. Limited evidence shows that ETBE has low toxicity. Acetaldehyde (AA), however, as one primary metabolite of ETBE, is clearly genotoxic and has been considered to be a potential carcinogen. The aim of this study was to evaluate the effects of ALDH2 gene on ETBE-induced genotoxicity and metabolism of its metabolites after inhalation exposure to ETBE. A group of wild-type (WT) and Aldh2 knockout (KO) C57BL/6 mice were exposed to 500ppm ETBE for 1-6h, and the blood concentrations of ETBE metabolites, including AA, tert-butyl alcohol and 2-methyl-1,2-propanediol, were measured. Another group of mice of WT and KO were exposed to 0, 500, 1750, or 5000ppm ETBE for 6h/day with 5 days per weeks for 13 weeks. Genotoxic effects of ETBE in these mice were measured by the alkaline comet assay, 8-hydroxyguanine DNA-glycosylase modified comet assay and micronucleus test. With short-term exposure to ETBE, the blood concentrations of all the three metabolites in KO mice were significantly higher than the corresponding concentrations of those in WT mice of both sexes. After subchronic exposure to ETBE, there was significant increase in DNA damage in a dose-dependent manner in KO male mice, while only 5000ppm exposure significantly increased DNA damage in male WT mice. Overall, there was a significant sex difference in genetic damage in both genetic types of mice. These results showed that ALDH2 is involved in the detoxification of ETBE and lack of enzyme activity may greatly increase the sensitivity to the genotoxic effects of ETBE, and male mice were more sensitive than females. PMID:23810710

  5. Ethyl t-butyl ether: review of reproductive and developmental toxicity.

    PubMed

    de Peyster, Ann

    2010-06-01

    Ethyl t-butyl ether (ETBE) is a motor fuel oxygenate used in reformulated gasoline. Knowledge of developmental and reproductive toxicity potential of ETBE is critical for making informed decisions about acceptance and regulations. This review discusses toxicology studies providing information about effects on reproduction and the conceptus. Seven GLP-compliant studies following widely accepted protocols have focused specifically on developmental and reproductive toxicity (DART) in rats and rabbits exposed to ETBE by gavage with doses up to 1,000 mg/kg body weight/day, the limit specified in standardized test guidelines. Other repeat-dose general toxicology studies have administered ETBE to rodents for up to 180 days, and included reproductive organ weights, histology, or other indications of reproductive system structure or function. DART potential of the main ETBE metabolite t-butyl alcohol and class-related MTBE has also been studied. More GLP-compliant studies exist for evaluating ETBE using well-established, currently recommended protocols than are available for many other chemicals used today. The database for determining ETBE DART potential is adequate, although not all study details are currently easily accessible for peer-review. ETBE does not appear to be selectively toxic to reproduction or embryofetal development in the absence of other manifestations of general toxicity. Studies using recommended methods for sample preservation and analysis have shown no targeted effect on the reproductive system. No embryofetal effects were observed in rabbits. Early postnatal rat pup deaths show no clear dose-response and have largely been attributed to total litter losses with accompanying evidence of maternal neglect or frank maternal morbidity. PMID:20544807

  6. Propargyl Vinyl Ethers and Tertiary Skipped Diynes: Two Pluripotent Molecular Platforms for Diversity-Oriented Synthesis.

    PubMed

    Tejedor, David; López-Tosco, Sara; Méndez-Abt, Gabriela; Cotos, Leandro; García-Tellado, Fernando

    2016-04-19

    During the last years, we have been involved in the development of a diversity-oriented synthetic strategy aimed at transforming simple, linear, and densely functionalized molecular platforms into collections of topologically diverse scaffolds incorporating biologically relevant structural motifs such as N- and O- heterocycles, multifunctionalized aromatic rings, fused macrocycles, etc. The strategy merges the concepts of pluripotency (the property of an array of chemical functionalities to express different chemical outcomes under different chemical environments) and domino chemistry (chemistry based on processes involving two or more bond-forming transformations that take place while the initial reaction conditions are maintained, with the subsequent reaction resulting as a consequence of the functionality installed in the previous one) to transform common multifunctional substrates into complex and diverse molecular frameworks. This design concept constitutes the ethos of the so-called branching cascade strategy, a branch of diversity-oriented synthesis focused on scaffold diversity generation. Two pluripotent molecular platforms have been extensively studied under this merging (branching) paradigm: C4-O-C3 propargyl vinyl ethers (PVEs) and C7 tertiary skipped diynes (TSDs). These are conveniently constructed from simple and commercially available raw materials (alkyl propiolates, ketones, aldehydes, acid chlorides) through multicomponent manifolds (ABB' three-component reaction for PVEs; A2BB' four-component reaction for TSDs) or a simple two-step procedure (for PVEs). Their modular origin facilitates their structural/functional diversification without increasing the number of synthetic steps for their assembly. These two pluripotent molecular platforms accommodate a well-defined and dense array of through-bond/through-space interrelated functionalities on their structures, which defines their primary reactivity principles and establishes the reactivity profile

  7. Gold(I)-Catalyzed Angle Strain Controlled Strategy to Furopyran Derivatives from Propargyl Vinyl Ethers: Insight into the Regioselectivity of Cycloisomerization.

    PubMed

    Jin, Shengfei; Jiang, Chongguo; Peng, Xiaoshi; Shan, Chunhui; Cui, Shanshan; Niu, Yuanyuan; Liu, Yang; Lan, Yu; Liu, Yongxiang; Cheng, Maosheng

    2016-02-19

    A unique strategy for the regiospecific synthesis of bicyclic furopyran derivatives has been developed via a gold(I)-catalyzed propargyl-Claisen rearrangement/6-endo-trig cyclization of propargyl vinyl ethers. The introduction of angle strain into the substrates significantly altered the reaction's regioselectivity. Insight into the regioselectivity of the cycloisomerization was obtained with density functional theory calculations. PMID:26841301

  8. Microwave-Assisted Organocatalyzed Rearrangement of Propargyl Vinyl Ethers to Salicylaldehyde Derivatives: An Experimental and Theoretical Study.

    PubMed

    Tejedor, David; Cotos, Leandro; Márquez-Arce, Daniel; Odriozola-Gimeno, Mikel; Torrent-Sucarrat, Miquel; Cossío, Fernando P; García-Tellado, Fernando

    2015-12-01

    The microwave-assisted imidazole-catalyzed transformation of propargyl vinyl ethers (PVEs) into multisubstituted salicylaldehydes is described. The reaction is instrumentally simple, scalable, and tolerates a diverse degree of substitution at the propargylic position of the starting PVE. The generated salicylaldehyde motifs incorporate a broad range of topologies, spanning from simple aromatic monocycles to complex fused polycyclic systems. The reaction is highly regioselective and takes place under symmetry-breaking conditions. The preparative power of this reaction was demonstrated in the first total synthesis of morintrifolin B, a benzophenone metabolite isolated from the small tree Morinda citrifolia L. A DFT study of the reaction was performed with full agreement between calculated values and experimental results. The theoretically calculated values support a domino mechanism comprising a propargyl Claisen rearrangement, a [1,3]-H shift, a [1,7]-H shift (enolization), a 6π electrocyclization, and an aromatization reaction. PMID:26515241

  9. Colloidal Properties of Aqueous Poly(vinyl acetate)-Borate Dispersions with Short-Chain Glycol Ethers.

    PubMed

    Duncan, Teresa T; Berrie, Barbara H; Weiss, Richard G

    2016-08-18

    We report the influence of adding five short-chain glycol ethers (SCGEs) on the structure, stability, and viscoelastic properties of aqueous dispersions of partially hydrolyzed poly(vinyl acetate) and borax. The properties of these gel-like materials have been investigated as a function of the structure of the added SCGE both below and above the critical aggregation (or micellar) concentrations using (11) B and (13) C NMR, rheology, and small-angle neutron scattering. The results indicate that the SCGE aggregation behavior is not affected by incorporation into the gel-like network. However, changes in the viscoelasticity and structural properties of the dispersions were detected that can be correlated to the nature of the solvent system. Also, the ability of these materials to clean an unvarnished acrylic paint surface coated with synthetic soil has been evaluated using colorimetery, and the surface of the dispersion after cleaning was visualized with scanning electron microscopy. PMID:27387383

  10. Catalytic asymmetric Claisen rearrangement of Gosteli-type allyl vinyl ethers: total synthesis of (-)-9,10-dihydroecklonialactone B.

    PubMed

    Becker, Julia; Butt, Lena; von Kiedrowski, Valeska; Mischler, Elisabeth; Quentin, Florian; Hiersemann, Martin

    2014-04-01

    The enantioselective synthesis of (-)-9,10-dihydroecklonialactone B is described. The catalytic asymmetric Claisen rearrangement of a Gosteli-type allyl vinyl ether was utilized to afford an acyclic α-keto ester building block endowed with functionality amenable to the preparation of the carbocyclic target molecule by suitable postrearrangement transformations: A highly diastereoselective Corey-Bakshi-Shibata reduction of a β-chiral α-keto ester and a reductive homologation of an α-hydroxy ester. A transprotection tactic by a chemoselective intramolecular 6-exo-trig iodoetherification enabled regioselective ring-closing alkene metatheses to afford the 5- as well as the 14-membered ring, however, with mixed success in terms of E/Z selectivity. PMID:24621347

  11. Development of a Vinyl Ether-Functionalized Polyphosphoester as a Template for Multiple Postpolymerization Conjugation Chemistries and Study of Core Degradable Polymeric Nanoparticles

    PubMed Central

    2015-01-01

    A novel polyphosphoester (PPE) with vinyl ether side chain functionality was developed as a versatile template for postpolymerization modifications, and its degradability and biocompatibility were evaluated. An organocatalyzed ring-opening polymerization of ethylene glycol vinyl ether-pendant cyclic phosphotriester monomer allowed for construction of poly(ethylene glycol vinyl ether phosphotriester) (PEVEP). This vinyl ether-functionalized PPE scaffold was coupled with hydroxyl- or thiol-containing model small molecules via three different types of conjugation chemistries—thiol–ene “click” reaction, acetalization, or thio-acetalization reaction—to afford modified polymers that accommodated either stable thio–ether or hydrolytically labile acetal or thio–acetal linkages. Amphiphilic diblock copolymers of poly(ethylene glycol) and PEVEP formed well-defined micelles with a narrow and monomodal size distribution in water, as confirmed by dynamic light scattering (DLS), transmission electron microscopy, and atomic force microscopy. The stability of the micelles and the hydrolytic degradability of the backbone and side chains of the PEVEP block segment were assessed by DLS and nuclear magnetic resonance spectroscopy (1H and 31P), respectively, in aqueous buffer solutions at pH values of 5.0 and 7.4 and at temperatures of 25 and 37 °C. The hydrolytic degradation products of the PEVEP segments of the block copolymers were then identified by electrospray ionization, gas chromatography, and matrix-assisted laser desorption/ionization mass spectrometry. The parent micelles and their degradation products were found to be non-cytotoxic at concentrations up to 3 mg/mL, when evaluated with RAW 264.7 mouse macrophages and OVCAR-3 human ovarian adenocarcinoma cells. PMID:25601803

  12. Poly(arlyene ether sulfone) based semi-interpenetrating polymer network membranes containing cross-linked poly(vinyl phosphonic acid) chains for fuel cell applications at high temperature and low humidity conditions

    NASA Astrophysics Data System (ADS)

    Kim, Kihyun; Heo, Pilwon; Ko, Taeyun; Kim, Ki-hyun; Kim, Sung-Kon; Pak, Chanho; Lee, Jong-Chan

    2015-10-01

    Semi-interpenetrating polymer network (semi-IPN) membranes are prepared by in-situ casting and thermal-initiated radical polymerization of vinyl phosphonic acid (VPA) and bis(2-(methacryloyloxy)ethyl) phosphate (BMAEP) in N,N-dimethylacetamide solutions of sulfonated poly(arylene ether sulfone) (SPAES). The incorporation of VPA units into the SPAES membranes improves proton conductivity especially at high temperature and low humidity conditions. In addition the cross-linker, BMAEP, prevents the decrease of the mechanical and chemical stabilities by the aliphatic linear poly(vinyl phosphonic acid) chains in the semi-IPN membranes, and furthermore the phosphonic acid group in BMAEP can prevent the decrease of the proton conductivity by the formation of cross-linked structures. Therefore, the resulting semi-IPN membranes show high proton conductivities up to 15 mS cm-1 at 120 °C and 40% RH. The fuel cell performance (187 mW cm-2 at 120 °C and 40% RH) of membrane-electrode assembly (MEA) from the semi-IPN membrane is found to be superior to that (145 mW cm-2 at 120 °C and 40% RH) of MEA from the SPAES membrane. The durability test result at the operating conditions indicates that the semi-IPN membrane is electrochemically very stable maintaining the low hydrogen cross-over and high power densities.

  13. Synthetic applications of aqueous accelerated [3,3] sigmatropic rearrangements of allyl vinyl ethers. [1,3] sigmatropic rearrangements of allyl vinyl ethers in 3 M lithium perchlorate-diethyl ether at ambient temperature. New methods to effect the retro Diels-Alder reaction of N-alkyl-2-azanorbornenes

    SciTech Connect

    Clark, J.D.

    1992-01-01

    Claisen rearrangements employed in the synthesis of natural and unnatural products that were heretofore difficult or impossible using conventional means are realized through the agency of water. Allyl vinyl ether 35, the unprotected form of McMurry's aphidicolin intermediate 7, rearranged after 24 h in 2.5:1 water/methanol at 80[degrees]C, affording aldehyde 40 in 70--85% yield. Acetaldehyde elimination witnessed using conventional reaction conditions was suppressed when employing water. The application of a Claisen rearrangement within the molecular framework of fenestranes was realized for the first time. Fenestrene vinyl ethers 28 and 30 rearranged to form the fenestrenes 29 and 31, respectively. Noteworthy is fenestrene 29, the first fenestrane synthesized possessing a trans-ring fusion common to two five-membered rings. The medium of 3.0 M lithium perchlorate-diethyl ether has been found to induce the rarely witnessed rearrangement of allyl vinyl ethers, despite the fact that the corresponding sigmatropic rearrangement is energetically more favorable. Yields are very good; however, in some instances the sigmatropic rearrangement and elimination processes compete slightly. Results from the observed stereoselectivities, concentration effects on reaction rate, and a crossover study indicate that these shifts take place via dissociated ions followed by recombination, and that the observed stereoselectivities are a result of unequal steric effects in the transition states for recombination. Copper(II) and sulfonic acid ion exchange resins have been found to readily catalyze the heterocycloreversion of N-alkyl-2-azanorbornenes to the corresponding primary amines, eliminating the necessity of employing a reactive dienophile to trap out the released cyclopentadiene.

  14. Toxic effect and genotoxicity of the semisynthetic derivatives dillapiole ethyl ether and dillapiole n-butyl ether for control of Aedes albopictus (Diptera: Culicidae).

    PubMed

    da Fonseca Meireles, Sabrina; Domingos, Pedro Rauel Cândido; da Silva Pinto, Ana Cristina; Rafael, Míriam Silva

    2016-09-01

    Two derivatives of dillapiole, dillapiole ethyl ether (1KL39-B) and butyl ether-n dillapiole (1KL43-C), were studied for their toxicity and genotoxicity against Aedes albopictus, to help develop new strategies for the control of this potential vector of dengue and other arboviruses, because it is resistant to synthetic insecticides. Eggs and larvae exposed to different concentrations of 1KL39-B (25, 30, 50, 70, and 80μg/mL) and of 1KL43-C (12.5, 20, 25, 30 and 40μg/mL) exhibited toxicity and susceptibility, with 100% mortality. The LC50 was 55.86±1.57μg/mL for 1KL39-B and 25.60±1.24μg/mL for 1KL43-C, while the LC90 was 70.12μg/mL for 1KL39-B and 41.51μg/mL for 1KL43-C. The gradual decrease in oviposition of the females of the G1 to G4 generations was proportional to the increase in concentrations of these compounds, which could be related to the cumulative effect of cell anomalies in neuroblasts and oocytes (P<0.05), including micronuclei, budding, multinucleated cells and nuclear bridges. These findings showed that both 1KL39-B and 1KL43-C can serve as potential alternatives in the control of A. albopictus. PMID:27542709

  15. The thickening additives for mineral and synthetic oils based on the copolymers of alkyl acrylates or methacrylates and butyl vinyl ether

    NASA Astrophysics Data System (ADS)

    Geraskina, Evgeniya V.; Moikin, Alexey A.; Semenycheva, Ludmila L.

    2014-05-01

    A new method for synthesizing of the copolymers of acrylic and methacrylic acid esters with butyl vinyl ether in an excess of low-boiling monomer, which has proven effective for a number of alkyl methacrylates was proposed. Tests of thickening efficiency of the obtained copolymers were carried out. The resistance to mechanical degradation of the mineral, semi synthetic and synthetic base oils doped with the copolymers was evaluated.

  16. Cyclic α-Alkoxyphosphonium Salts from (2-(Diphenylphosphino)phenyl)methanol and Aldehydes and Their Application in Synthesis of Vinyl Ethers and Ketones via Wittig Olefination.

    PubMed

    Huang, Wenhua; Rong, Hong-Ying; Xu, Jie

    2015-07-01

    Cyclic α-alkoxyphosphonium salts have been synthesized from (2-(diphenylphosphino)phenyl)methanol and aldehydes in 36-89% yields. These phosphonium salts are bench-stable solids and undergo Wittig olefination with aldehydes under basic conditions (K2CO3 or t-BuOK) to form benzylic vinyl ethers, which are readily hydrolyzed to 1,2-disubstituted ethanones under acidic conditions. The formation mechanism of these phosphonium salts via hemiacetal is also proposed. PMID:26067375

  17. Bismuth-catalyzed synthesis of polycyclic aromatic hydrocarbons (PAHs) with a phenanthrene backbone via cyclization and aromatization of 2-(2-arylphenyl)vinyl ethers.

    PubMed

    Murai, Masahito; Hosokawa, Naoki; Roy, David; Takai, Kazuhiko

    2014-08-15

    The reaction of 2-(2-arylphenyl)vinyl ethers in the presence of a catalytic amount of bismuth(III) triflate gave substituted phenanthrenes in excellent yields under mild reaction conditions. The reaction was also applied to the construction of other polycyclic aromatic hydrocarbons (PAHs), such as chrysene, helicene, and pyrene having a phenanthrene backbone, via regioselective cyclization. This method has the advantages of easy availability of the cyclization precursors, operational simplicity, and high reaction efficiency. PMID:25076204

  18. Prolonged Hypocalcemic Effect by Pulmonary Delivery of Calcitonin Loaded Poly(Methyl Vinyl Ether Maleic Acid) Bioadhesive Nanoparticles

    PubMed Central

    Varshosaz, J.; Minaiyan, M.; Forghanian, M.

    2014-01-01

    The purpose of the present study was to design a pulmonary controlled release system of salmon calcitonin (sCT). Therefore, poly(methyl vinyl ether maleic acid) [P(MVEMA)] nanoparticles were prepared by ionic cross-linking method using Fe2+ and Zn2+ ions. Physicochemical properties of nanoparticles were studied in vitro. The stability of sCT in the optimized nanoparticles was studied by electrophoretic gel method. Plasma calcium levels until 48 h were determined in rats as pulmonary-free sCT solution or nanoparticles (25 μg·kg−1), iv solution of sCT (5 μg·kg−1), and pulmonary blank nanoparticles. The drug remained stable during fabrication and tests on nanoparticles. The optimized nanoparticles showed proper physicochemical properties. Normalized reduction of plasma calcium levels was at least 2.76 times higher in pulmonary sCT nanoparticles compared to free solution. The duration of hypocalcemic effect of pulmonary sCT nanoparticles was 24 h, while it was just 1 h for the iv solution. There was not any significant difference between normalized blood calcium levels reduction in pulmonary drug solution and iv injection. Pharmacological activity of nanoparticles after pulmonary delivery was 65% of the iv route. Pulmonary delivery of P(MVEMA) nanoparticles of sCT enhanced and prolonged the hypocalcemic effect of the drug significantly. PMID:24701588

  19. Immobilization of saccharides and peptides on 96-well microtiter plates coated with methyl vinyl ether-maleic anhydride copolymer.

    PubMed

    Satoh, A; Kojima, K; Koyama, T; Ogawa, H; Matsumoto, I

    1998-06-15

    We have previously reported a method to immobilize protein ligands on microtiter plates coated with methyl vinyl ether-maleic anhydride copolymer (MMAC) [Isosaki, K., et al. (1992) J. Chromatogr. 597, 123-128]. In this study, we improved the MMAC method to efficiently immobilize not only small ligands such as peptides and oligosaccharides, which could not be efficiently immobilized previously, but also heparin via its reducing end. Amino and hydrazino groups were introduced to MMAC-coated microtiter plate wells by coupling to acid anhydride groups of MMAC with 1,6-hexamethylenediamine and adipic acid dihydrazide, respectively. The amino groups introduced were allowed to react with peptides by use of divalent cross-linkers. Hydrazino groups were allowed to react with formyl groups of saccharides by reductive amination. Peptides and oligosaccharides were immobilized in a dose-dependent manner by these methods. In the case of the angiotensin peptide thus immobilized, the detection limit by monoclonal antibodies was as low as 0.1-1 fmol peptide per well. Application of 20-200 nmol oligosaccharides to the well was sufficient to immobilize and subsequently detect lectins. Furthermore, heparin immobilized on the hydrazinocoated wells was successfully used for the binding assay of annexin IV. PMID:9648659

  20. Understanding How the Presence of Uniform Electric Fields Can Shift the Miscibility of Polystyrene/Poly(vinyl methyl ether) Blends

    NASA Astrophysics Data System (ADS)

    Kriisa, Annika; Roth, Connie B.

    2015-03-01

    Techniques which can externally control and manipulate the phase behavior of polymeric systems, without altering chemistry on a molecular level, have great practical benefits. One such possible mechanism is the use of electric fields, shown to cause interfacial instabilities, orientation of morphologies, and phase transitions in polymer blends and block copolymers. We have recently demonstrated that the presence of uniform electric fields can also strongly enhance the miscibility of polystyrene (PS) / poly(vinyl methyl ether) (PVME) blends [J. Chem. Phys. 2014, 141, 134908]. Using fluorescence to measure the phase separation temperature Ts of PS/PVME blends with and without electric fields, we show that Ts can be reproducibly and reversibly increased by 13.5 +/- 1.4 K for electric fields of 17 kV/mm for this lower critical solution temperature (LCST) blend. This increase in blend miscibility with electric fields represents some of the largest absolute shifts in Ts ever recorded, well outside of experimental error. The best theoretical prediction for the expected shift in Ts with electric field for this system is still two orders of magnitude smaller than that observed experimentally. We discuss the limitations of this theoretical prediction and consider possible factors affecting miscibility that may need to be also included.

  1. A subchronic (180-day) oral toxicity study of ethyl tertiary-butyl ether, a bioethanol, in rats.

    PubMed

    Miyata, Katsumi; Koga, Takayuki; Aso, Sunao; Hoshuyama, Satsuki; Ajimi, Syozo; Furukawa, Kotaro

    2014-07-01

    A subchronic (180-day) toxicity study was conducted to evaluate the effects of ethyl tertiary-butyl ether (ETBE), a biomass fuel, in male and female rats. ETBE was administered at dose levels of 0, 5, 25, 100 and 400 mg/kg/body weight (b.w.)/day by gavage. No treatment-related adverse effects were observed at 5, 25 or 100 mg/kg. Centrilobular hypertrophy of hepatocytes was observed in males and females and their relative liver weights were increased, suggesting enhanced metabolic activity. From these results, we concluded that the no observed adverse effect level of ETBE was 100 mg/kg b.w./day under the conditions tested. PMID:24252074

  2. Ethyl tert-butyl ether (ETBE) synthesis on H-Mordenite: Gas-phase kinetics and DRIFTS studies

    SciTech Connect

    Larsen, G.; Lotero, E.; Marquez, M.

    1995-12-01

    The ethyl tert-butyl ether (ETBE) formation between 313 and 363 K over an H-mordenite catalyst was studied in a packed-bed flow catalytic reactor at atmospheric pressure. An activation energy of 82 kJ/mol and reaction orders in isobutene and ethanol of 0.8 and -0.8 were found. In situ diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) was used to study the state of the catalyst under reaction conditions. The IR studies, coupled with the reaction kinetics information, are consistent with the idea that the stability of the H-mordenite catalyst requires the protective action of ethanol to prevent the occurrence of isobutene oligomerization products. The high ethanol concentrations found in the zeolite pores under the temperature and pressure conditions employed is also responsible for reaction inhibition. 27 refs., 13 figs., 1 tab.

  3. Addition of dimethylsulphoxide to methyl-tert-butyl ether and ethyl propionate increases cholesterol dissolving capacity and cholesterol gall stone dissolution in vitro.

    PubMed Central

    Bergman, J J; Groen, A K; Huibregtse, K; Tytgat, G N

    1994-01-01

    There is a discrepancy between in vitro cholesterol dissolving efficacy of methyl-tert-butyl ether (MTBE) and ethyl propionate and cholesterol gall stone dissolution in vivo. This study investigated whether the presence of bile changes the cholesterol dissolving capacity of MTBE and ethyl propionate. The addition of dimethylsulphoxide to MTBE or ethyl propionate was also studied to discover if it improves the dissolving capacity for cholesterol gall stones. The presence of bile caused a 25% decrease in cholesterol dissolving capacity of both MTBE and ethyl propionate (p < 0.0001). This inhibitory effect of bile could be overcome by the addition of dimethyl-sulphoxide: dimethylsulphoxide caused an increase in cholesterol dissolving capacity of MTBE and ethyl propionate, the increase depending on the dimethyl-sulphoxide/bile ratio in the mixture. Mean dissolution time of weight, size, and patient matched cholesterol gall stones was 220 minutes in MTBE and 130 minutes in MTBE/dimethylsulphoxide (p < 0.0001). No stones dissolved completely in ethyl propionate or ethyl propionate/dimethyl-sulphoxide within 300 minutes. In conclusion, MTBE/dimethylsulphoxide is a more potent dissolving agent for cholesterol gall stones than MTBE, giving a 40% reduction in dissolution time. Addition of dimethylsulphoxide to ethyl propionate does not result in faster stone dissolution. MTBE and MTBE/dimethylsulphoxide are far superior to ethyl propionate as solvents for cholesterol gall stones. PMID:7828992

  4. 46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Additional requirements for carbon disulfide (carbon... Special Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl... waterways at the loading and unloading points. (f) The special requirements of § 151.50-41 for...

  5. 46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Additional requirements for carbon disulfide (carbon... Special Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl... waterways at the loading and unloading points. (f) The special requirements of § 151.50-41 for...

  6. 46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Additional requirements for carbon disulfide (carbon... Special Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl... waterways at the loading and unloading points. (f) The special requirements of § 151.50-41 for...

  7. 46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Additional requirements for carbon disulfide (carbon... Special Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl... waterways at the loading and unloading points. (f) The special requirements of § 151.50-41 for...

  8. 46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Additional requirements for carbon disulfide (carbon... Special Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl... waterways at the loading and unloading points. (f) The special requirements of § 151.50-41 for...

  9. Competition between Reaction and Intramolecular Energy Redistribution in Solution. Observation and Nature of Nonstatistical Dynamics in the Ozonolysis of Vinyl Ethers

    PubMed Central

    Quijano, Larisa Mae M.; Singleton, Daniel A.

    2011-01-01

    Experimental product ratios in ozonolyses of alkyl vinyl ethers in solution do not fit with expectations from statistical rate theories. The selectivity among cleavage pathways increases with the size of the alkyl group but to an extent that is far less than RRKM theory would predict. Trajectory studies account for the observed selectivities and support a mechanism involving a competition between cleavage of the primary ozonide and intramolecular vibrational energy redistribution. An approximate statistical model is presented that assumes that RRKM theory holds for a molecular subset of the primary ozonides, allowing estimates of the rates of energy loss from the primary ozonides based on the observed product ratios. PMID:21812422

  10. Reaction products and mechanisms for the reaction of n-butyl vinyl ether with the oxidants OH and Cl: Atmospheric implications

    NASA Astrophysics Data System (ADS)

    Colmenar, Inmaculada; Martín, Pilar; Cabañas, Beatriz; Salgado, Sagrario; Tapia, Araceli; Martínez, Ernesto

    2015-12-01

    A reaction product study for the degradation of butyl vinyl ether (CH3(CH2)3OCHdbnd CH2) by reaction with chlorine atoms (Cl) and hydroxyl radicals (OH) has been carried out using Fourier Transform Infrared absorption spectroscopy (FTIR) and/or Gas Chromatography-Mass Spectrometry with a Time of Flight analyzer (GC-TOFMS). The rate coefficient for the reaction of butyl vinyl ether (BVE) with chlorine atoms has also been evaluated for the first time at room temperature (298 ± 2) K and atmospheric pressure (708 ± 8) Torr. The rate coefficient obtained was (9.9 ± 1.5) × 10-10 cm3 molecule-1 s-1 and this indicates the high reactivity of butyl vinyl ether with Cl atoms. However, this value may be affected by the dark reaction of BVE with Cl2. The results of a qualitative study of the Cl reaction show that the main oxidation products are butyl formate (CH3(CH2)3OC(O)H), butyl chloroacetate (CH3(CH2)3OC(O)CH2Cl and formyl chloride (HCOCl). Individual yields in the ranges ∼16-40% and 30-70% in the absence and presence of NOx, respectively, have been estimated for these products. In the OH reaction, butyl formate and formic acid were identified as the main products, with yields of around 50 and 20%, respectively. Based on the results of this work and a literature survey, the addition of OH radicals and Cl atoms at the terminal C atom of the double bond in CH3(CH2)3OCHdbnd CH2 has been proposed as the first step in the reaction mechanism for both of the studied oxidants. The tropospheric lifetime of butyl vinyl ether is very short and, as a consequence, it will be rapidly degraded and will only be involved in tropospheric chemistry at a local level. The degradation products of these reactions should be considered when evaluating the atmospheric impact.

  11. Competition between reaction and intramolecular energy redistribution in solution: observation and nature of nonstatistical dynamics in the ozonolysis of vinyl ethers.

    PubMed

    Quijano, Larisa Mae M; Singleton, Daniel A

    2011-09-01

    Experimental product ratios in ozonolyses of alkyl vinyl ethers in solution do not fit with expectations based on statistical rate theories. The selectivity among cleavage pathways increases with the size of the alkyl group but to an extent that is far less than RRKM theory would predict. Trajectory studies account for the observed selectivities and support a mechanism involving a competition between cleavage of the primary ozonide and intramolecular vibrational energy redistribution. A statistical model is presented that assumes that RRKM theory holds for a molecular subset of the primary ozonides, allowing the rates of energy loss from the ozonides to be estimated from the observed product ratios. PMID:21812422

  12. Volumetric Properties of the Mixture Propan-1-ol C3H8O + C5H10O Propyl vinyl ether (VMSD1111, LB5079_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propan-1-ol C3H8O + C5H10O Propyl vinyl ether (VMSD1111, LB5079_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  13. Volumetric Properties of the Mixture Propan-1-ol C3H8O + C5H10O Propyl vinyl ether (VMSD1212, LB5078_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propan-1-ol C3H8O + C5H10O Propyl vinyl ether (VMSD1212, LB5078_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  14. Vapor-Liquid Equilibrium in the Mixture Propyl vinyl ether C5H10O + C6H6 Benzene (EVLM1121, LB5723_E)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'vapor-liquid Equilibrium in the Mixture Propyl vinyl ether C5H10O + C6H6 Benzene (EVLM1121, LB5723_E)' providing data from direct measurement of mole fraction in vapor phase at variable mole fraction in liquid phase and constant temperature.

  15. Copper(I)/Ligand-Catalyzed 5-endo Radical Cyclization-Aromatization of 2,2,2-Trichloroethyl Vinyl Ethers: Synthesis of 2,3-Difunctionalized 4-Chlorofurans.

    PubMed

    Ram, Ram N; Gupta, Dharmendra Kumar; Soni, Vineet Kumar

    2016-02-19

    Copper(I)/ligand-catalyzed one pot synthesis of highly substituted 2,3-difunctionalized-4-chlorofurans has been reported. The reaction proceeds via a Cu(I)-catalyzed regioselective 5-endo-trig radical cyclization of 2,2,2-trichloroethyl vinyl ethers followed by the base-promoted dehydrochlorination. The success of the kinetically disfavored 5-endo cyclization was attributed to the formation of captodatively stabilized radical intermediate in the cyclization step and relatively high reaction temperature. Synthetic application of this protocol was also demonstrated in the preparation of alkyl and aryl substituted 4-chlorofuranonapthoquinones. PMID:26796068

  16. Volumetric Properties of the Mixture Propyl vinyl ether C5H10O + C6H6 Benzene (VMSD1212, LB5077_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propyl vinyl ether C5H10O + C6H6 Benzene (VMSD1212, LB5077_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  17. Vapor-Liquid Equilibrium in the Mixture Propan-1-ol C3H8O + C5H10O Propyl vinyl ether (EVLM1121, LB5724_E)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'vapor-Liquid Equilibrium in the Mixture Propan-1-ol C3H8O + C5H10O Propyl vinyl ether (EVLM1121, LB5724_E)' providing data from direct measurement of mole fraction in vapor phase at variable mole fraction in liquid phase and constant temperature.

  18. Volumetric Properties of the Mixture Propyl vinyl ether C5H10O + C6H6 Benzene (VMSD1111, LB5076_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propyl vinyl ether C5H10O + C6H6 Benzene (VMSD1111, LB5076_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  19. Promotion of liver and kidney carcinogenesis by ethyl tertiary-butyl ether (ETBE) in male Wistar rats

    PubMed Central

    Hagiwara, Akihiro; Doi, Yuko; Imai, Norio; Suguro, Mayuko; Kawabe, Mayumi; Furukawa, Fumio; Tamano, Seiko; Nagano, Kasuke; Fukushima, Shoji

    2015-01-01

    Tumor-promoting effects of ethyl tertiary-butyl ether (ETBE) were investigated in a 2-stage carcinogenesis bioassay with regard to hepatic and renal carcinogenesis in rats. Male 6-week-old Wistar rats were given drinking water containing N-ethyl-N-(2-hydroxyethyl)nitrosamine (EHEN), as an initiator, at a dose of 500 ppm for 2 weeks. Starting one week thereafter, the animals were administered ETBE at dose levels of 0 (control), 100, 300, 500 or 1,000 mg/kg/day by gavage for 19 weeks from week 4 to 22. Necropsy of all rats was performed at week 23, and livers and kidneys were examined histopathologically. Incidences of hepatocellular adenomas, and those of combined hepatocellular adenomas and carcinomas were significantly elevated in rats given 1,000 mg/kg/day ETBE, but not 100‒500 mg/kg/day ETBE, and there was a significant increase in the average numbers of lesions. No significant differences in incidences and average numbers of renal tubule neoplasms were found in rats administered 100‒1,000 mg/kg/day ETBE. However, the average numbers of atypical tubule hyperplasias, considered to be preneoplastic lesions, were significantly increased in rats given ETBE at 1,000 mg/kg/day, but not in rats given 500 mg/kg/day or lower doses. Thus, these results imply that ETBE has hepatic and renal tumor-promoting activities that affect EHEN-induced carcinogenesis in male rats, and the no-observed-effect level is 500 mg/kg/day under the present experimental conditions. PMID:26538808

  20. Induction of cell proliferation in the rat liver by the short-term administration of ethyl tertiary-butyl ether

    PubMed Central

    Kakehashi, Anna; Hagiwara, Akihiro; Imai, Norio; Wei, Min; Fukushima, Shoji; Wanibuchi, Hideki

    2015-01-01

    In the present study, in continuation of our previous experiment in order to investigate the mode of action (MOA) of ethyl tertiary-butyl ether (ETBE) hepatotumorigenicity in rats, we aimed to examine alterations in cell proliferation, that are induced by short-term administration of ETBE. F344 rats were administered ETBE at doses of 0, and 1,000 mg/kg body weight twice a day by gavage for 3, 10, 17 and 28 days. It was found that the previously observed significant increase of P450 total content and hydroxyl radical levels after 7 days of ETBE administration, and 8-OHdG formation at day 14, accompanied by accumulation of CYP2B1/2B2, CYP3A1/3A2, CYP2C6, CYP2E1 and CYP1A1 and downregulation of DNA oxoguanine glycosylase 1, was preceded by induction of cell proliferation at day 3. Furthermore, we observed an increase in regenerative cell proliferation as a result of ETBE treatment at day 28, followed by induction of cell cycle arrest and apoptosis by day 14. These results indicated that short-term administration of ETBE led to a significant early increase in cell proliferation activity associated with induction of oxidative stress, and to a regenerative cell proliferation as an adaptive response, which could contribute to the hepatotumorigenicity of ETBE in rats. PMID:26023258

  1. Aldh2 knockout mice were more sensitive to DNA damage in leukocytes due to ethyl tertiary butyl ether exposure.

    PubMed

    Weng, Zuquan; Suda, Megumi; Ohtani, Katsumi; Mei, Nan; Kawamoto, Toshihiro; Nakajima, Tamie; Wang, Rui-Sheng

    2011-01-01

    To clarify the genotoxicity of ethyl tertiary butyl ether (ETBE), a gasoline additive, male and female C57BL/6 mice of Aldh2+/+ and Aldh2-/- genotypes, aged 8 wk, were exposed to 0, 500, 1,750, or 5,000 ppm ETBE for 6 h/day, 5 d per week for 13 wk. DNA damage in leukocytes was measured by the alkaline comet assay and expressed quantitatively as Tail Intensity (TI). For male mice, TI was significantly higher in all three groups exposed to ETBE than in those without exposure within Aldh2-/- mice, whereas within Aldh2+/+ mice, TI increased only in those exposed to 5,000 ppm of ETBE as compared with mice without exposure. For female mice, a significant increase in TI values was observed in the group exposed to 5,000 ppm of ETBE as compared with those without exposure within Aldh2-/- mice; TI in Aldh2-/- mice exposed to 1,750 and 5,000 ppm was significantly higher than in Aldh2+/+ mice without exposure. TI did not significantly increase in any of the groups exposed to ETBE within female Aldh2+/+ mice. Based on the results we suggest that Aldh2-/- mice are more sensitive to DNA damage caused by ETBE than Aldh2+/+ mice and that males seem more susceptible to this effect than females. PMID:21372431

  2. Regioselective hydroformylation of cylic vinyl and allyl ethers with rhodium catalysts. Crucial influence of the size of the phosphorous cocatalyst

    SciTech Connect

    Polo, A.; Claver, C.; Castillon, S.

    1992-11-01

    The authors have explored the possibilities offered by the modification of thiolato bridges in dinuclear rhodium complexes on the selective hydroformylation of cylic vinyl and allyl ethers. The dinuclear complex [Rh{sub 2}({mu}-S(CH{sub 2}){sub 3}NMe{sub 2}){sub 2}(cod){sub 2}] (cod = 1,5-cyclooctadiene) has been prepared, and its reactivity with CO, phospines, and phosphites has been investigated. The complex crystallizes in the monoclinic space group C2/c with Z = 8, {alpha} = 22.543 (4) A, B = 12.040 (2) A, c = 21.547 (3) A, and {Beta} = 98.77 (1){degrees}. For the determination of the structure 4091 unique reflections were used, and the final refinement gave R = 4.1% and R{sub w} = 4.4%. The molecular structure reveals that the two rhodium atoms are bridged by the two thiolato ligands, and the cyclooctadiene completes the coordination of the metal atoms. The amine groups are not bonded to the rhodium. The dinuclear complex has been used in the hydroformylation of 2,3-di-hydrofuran, 2,5-dihydrofuran, 3,4-dihydro-2H-pyran or 3,6-dihydro-2H-pyran was tetrahydropyran-2-carbaldehyde. A systematic study of the influence of the reaction parameters on the selectivity of the hydroformylation of 2,3-dihydroformylation of 3,4-dihydro-2H-pyran or 3,6-dihydro-2H-pyran was tetrahydropyran-2-carbaldehyde. A systematic study of the influence of the reaction parameters on the selectivity of the hydroformylation of 2,3-dihydrofuran and 2,5-dihydrofuran was undertaken. The study allowed the rationalization of the observed selectivity and the optimization of the yields and regioselectivities. Thus, by modification of the reaction parameters, tetrahydrofuran-3-carbaldehyde was obtained in quantitative yields from 2,5-dihydrofuran and tetrahydrofuran-2-carbaldehyde can be prepared from either 2,3-dihydrofuran or 2,5-dihydrofuran in approximately 75% yield. 33 refs., 3 figs., 9 tabs.

  3. Poly(vinyl methyl ether) hydrogels at temperatures below the freezing point of water-molecular interactions and states of water.

    PubMed

    Pastorczak, Marcin; Dominguez-Espinosa, Gustavo; Okrasa, Lidia; Pyda, Marek; Kozanecki, Marcin; Kadlubowski, Slawomir; Rosiak, Janusz M; Ulanski, Jacek

    2014-01-01

    Water interacting with a polymer reveals a number of properties very different to bulk water. These interactions lead to the redistribution of hydrogen bonds in water. It results in modification of thermodynamic properties of water and the molecular dynamics of water. That kind of water is particularly well observable at temperatures below the freezing point of water, when the bulk water crystallizes. In this work, we determine the amount of water bound to the polymer and of the so-called pre-melting water in poly(vinyl methyl ether) hydrogels with the use of Raman spectroscopy, dielectric spectroscopy, and calorimetry. This analysis allows us to compare various physical properties of the bulk and the pre-melting water. We also postulate the molecular mechanism responsible for the pre-melting of part of water in poly(vinyl methyl ether) hydrogels. We suggest that above -60 °C, the first segmental motions of the polymer chain are activated, which trigger the process of the pre-melting. PMID:25100897

  4. Cross-Linked Hydrogels Formed through Diels-Alder Coupling of Furan- and Maleimide-Modified Poly(methyl vinyl ether-alt-maleic acid).

    PubMed

    Stewart, S Alison; Backholm, Matilda; Burke, Nicholas A D; Stöver, Harald D H

    2016-02-23

    The Diels-Alder [4 + 2] cycloaddition between furan- and maleimide-functional polyanions was used to form cross-linked synthetic polymer hydrogels. Poly(methyl vinyl ether-alt-maleic anhydride) was reacted with furfurylamine or N-(2-aminoethyl)maleimide in acetonitrile to form pairs of furan- and maleimide-functionalized poly(methyl vinyl ether-alt-maleic acid)s. Mixtures of these mutually reactive polyanions in water gelled within 15 min to 18 h, depending on degree of functionalization and polymer concentrations. Solution and magic-angle spinning (1)H NMR were used to confirm the formation of the Diels-Alder adduct, to analyze competing hydrolytic side reactions, and demonstrate postgelation functionalization. The effect of the degree of furan and maleimide functionalization, polymer concentration, pH, and calcium ion concentration, on gelation time, gel mechanical properties, and equilibrium swelling, are described. Release of dextran as a model drug was studied using fluorescence spectroscopy, as a function of gel composition and calcium treatment. PMID:26800849

  5. Spectra, stability and labeling of 1-(5-carboxypentyl)-4-(2-(N-ethyl-carbazole-3-yl) vinyl) pyridinium bromide with a large Stokes shift.

    PubMed

    Gu, Yingchun; Lin, Dayong; Li, Ran; Tang, Yalin; Fei, Xuening; Zhou, Jianguo

    2016-03-01

    Carbazole and its derivatives have been widely utilized as a functional building block in the fabrication of the organic medicine, pesticides, materials, etc., because of their excellent solubility, stability and biological activity. In this paper, 1-(5-carboxypentyl)-4-(2-(N-ethyl-carbazole-3-yl) vinyl) pyridinium bromide with a large Stokes shift was synthesized and characterized by (1) H NMR and MS. The UV/vis absorption and fluorescence spectra in different solvents and at different pH values were investigated preliminarily. The photostability and thermostability were also studied and the results showed that the compound was stable. The compound was also used to label bovine serum albumin (BSA) and calf thymus (ct)DNA. The results showed that the fluorescence intensity is enhanced when labeling with BSA and the binding ability is stronger than ctDNA, making it may be used as a biological probe. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26249113

  6. Oxidation-Responsive and "Clickable" Poly(ethylene glycol) via Copolymerization of 2-(Methylthio)ethyl Glycidyl Ether.

    PubMed

    Herzberger, Jana; Fischer, Karl; Leibig, Daniel; Bros, Matthias; Thiermann, Raphael; Frey, Holger

    2016-07-27

    Poly(ethylene glycol) (PEG) is a widely used biocompatible polymer. We describe a novel epoxide monomer with methyl-thioether moiety, 2-(methylthio)ethyl glycidyl ether (MTEGE), which enables the synthesis of well-defined thioether-functional poly(ethylene glycol). Random and block mPEG-b-PMTEGE copolymers (Mw/Mn = 1.05-1.17) were obtained via anionic ring opening polymerization (AROP) with molecular weights ranging from 5 600 to 12 000 g·mol(-1). The statistical copolymerization of MTEGE with ethylene oxide results in a random microstructure (rEO = 0.92 ± 0.02 and rMTEG E = 1.06 ± 0.02), which was confirmed by in situ (1)H NMR kinetic studies. The random copolymers are thermoresponsive in aqueous solution, with a wide range of tunable transition temperatures of 88 to 28 °C. In contrast, mPEG-b-PMTEGE block copolymers formed well-defined micelles (Rh ≈ 9-15 nm) in water, studied by detailed light scattering (DLS and SLS). Intriguingly, the thioether moieties of MTEGE can be selectively oxidized into sulfoxide units, leading to full disassembly of the micelles, as confirmed by detection of pure unimers (DLS and SLS). Oxidation-responsive release of encapsulated Nile Red demonstrates the potential of these micelles as redox-responsive nanocarriers. MTT assays showed only minor effects of the thioethers and their oxidized derivatives on the cellular metabolism of WEHI-164 and HEK-293T cell lines (1-1000 μg·mL(-1)). Further, sulfonium PEG polyelectrolytes can be obtained via alkylation or alkoxylation of MTEGE, providing access to a large variety of functional groups at the charged sulfur atom. PMID:27375132

  7. Atomic motions in poly(vinyl methyl ether): A combined study by quasielastic neutron scattering and molecular dynamics simulations in the light of the mode coupling theory.

    PubMed

    Capponi, S; Arbe, A; Alvarez, F; Colmenero, J; Frick, B; Embs, J P

    2009-11-28

    Quasielastic neutron scattering experiments (time-of-flight, neutron spin echo, and backscattering) on protonated poly(vinyl methyl ether) (PVME) have revealed the hydrogen dynamics above the glass-transition temperature. Fully atomistic molecular dynamics simulations properly validated with the neutron scattering results have allowed further characterization of the atomic motions accessing the correlation functions directly in real space. Deviations from Gaussian behavior are found in the high-momentum transfer range, which are compatible with the predictions of mode coupling theory (MCT). We have applied the MCT phenomenological version to the self-correlation functions of PVME atoms calculated from our simulation data, obtaining consistent results. The unusually large value found for the lambda-exponent parameter is close to that recently reported for polybutadiene and simple polymer models with intramolecular barriers. PMID:19947703

  8. Optical and dielectric properties of fluorinated ethylene propylene and tetrafluoroethylene-perfluoro(alkoxy vinyl ether) copolymer films modified by low energy N 4+ and C 4+ ion beams

    NASA Astrophysics Data System (ADS)

    Šiljegović, M.; Kačarević-Popović, Z. M.; Bibić, N.; Jovanović, Z. M.; Maletić, S.; Stchakovsky, M.; Krklješ, A. N.

    2011-12-01

    Fluorinated ethylene propylene (FEP) and tetrafluoroethylene-perfluoro(alkoxy vinyl ether) (PFA) copolymer films were irradiated in vacuum with 60 keV C 4+ and N 4+ ions to fluences ranging from 1.0×10 12 to 5.0×10 15 cm -2. Changes in optical and dielectric properties were analyzed by spectroscopic ellipsometry and ultraviolet-visible (UV-vis), Raman and dielectric relaxation spectroscopies. Direct and indirect energy band gap values were determined from the absorption edge in the 200-800 nm region using Tauc's relation. The values of the direct energy gap have been found to be greater than the corresponding values of the indirect energy gap. Significant changes in the index of refraction, and β and γ dielectric relaxations were observed in the case of N 4+ irradiated FEP and PFA samples.

  9. CF3+ fragmentation by electron impact ionization of perfluoro-propyl-vinyl-ethers, C5F10O, in gas phase

    NASA Astrophysics Data System (ADS)

    Kondo, Yusuke; Ishikawa, Kenji; Hayashi, Toshio; Miyawaki, Yudai; Takeda, Keigo; Kondo, Hiroki; Sekine, Makoto; Hori, Masaru

    2015-04-01

    The gas phase fragmentations of perfluoro-propyl-vinyl ether (PPVE, C5F10O) are studied experimentally. Dominant fragmentations of PPVE are found to be the result of a dissociative ionization reaction, i.e., CF3+ via direct bond cleavage, and C2F3O- and C3F7O- via electron attachment. Regardless of the appearance energy of around 14.5 eV for the dissociative ionization of CF3+, the observed ion efficiency for the CF3+ ion was extremely large the order of 10-20 cm-2, compared with only 10-21 cm-2 for the other channels. PPVE characteristically generated CF3+ as the largest abundant ion are advantageous for use of feedstock gases in plasma etching processes.

  10. Acid-Triggered Release via dePEGylation of Fusogenic Liposomes Mediated by Heterobifunctional Phenyl Substituted Vinyl Ethers with Tunable pH-Sensitivity

    PubMed Central

    Kim, Hee-Kwon; Van den Bossche, Jeroen; Hyun, Seok-Hee; Thompson, David H

    2012-01-01

    A new family of heterobifunctional phenyl-substituted vinyl ether (PIVE) coupling agents with tunable acid-sensitivity has been developed. The PIVE compounds are designed to hydrolyze under acidic conditions with hydrolysis rates that can be varied by rational selection of the phenyl ring substituent. These reagents were incorporated within 2-methoxypoly(ethylene glycol) PEG-conjugated 1,3-dioctadecyl-rac-glycerol lipids to produce the acid-cleavable lipopolymers mPEG-[H-PIVE]-DOG, mPEG-[F-PIVE]-DOG, mPEG-[Me-PIVE]-DOG, and mPEG-[MeO-PIVE]-DOG. These lipopolymers were hydrolyzed under acidic conditions (pH 3.5 or 4.5) at rates that were dependent on the electron donating or withdrawing character of the α-phenyl vinyl ether substituent, while remaining stable at pH 7.4. Blending of these compounds with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) in a 10:90 mPEG-PIVE-Lipid:DOPE ratio produced stable liposomes at neutral pH; however, acidification of the solution led to dePEGylation and release of the liposomal cargo in a manner that correlated with the PIVE proton affinity. Specifically, we observed 70 % calcein release within 12 h from mPEG-[MeO-PIVE]-DOG-containing liposomes at pH 4.5, whereas only 22% calcein release was observed from mPEG-[F-PIVE]-DOG:DOPE liposomes over this same timescale and pH. These results indicate that dePEGylation following acidification is a triggering mechanism that can be rationally designed and controlled through the appropriate selection of PIVE moieties. PMID:22988941

  11. Inorganic-organic polymer electrolytes based on poly(vinyl alcohol) and borane/poly(ethylene glycol) monomethyl ether for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Aydın, Hamide; Şenel, Mehmet; Erdemi, Hamit; Baykal, Abdülhadi; Tülü, Metin; Ata, Ali; Bozkurt, Ayhan

    In this study, poly(vinyl alcohol) (PVA) was modified with poly(ethylene glycol) monomethyl ether (PEGME) using borane-tetrahydrofuran (BH 3/THF) complex. Molecular weights of both PVA and PEGME were varied prior to reaction. Boron containing comb-branched copolymers were produced and abbreviated as PVA1PEGMEX and PVA2PEGMEX. Then polymer electrolytes were successfully prepared by doping of the host matrix with CF 3SO 3Li at several stoichiomeric ratios with respect to EO to Li. The materials were characterized via nuclear magnetic resonance (1H NMR and 11B NMR), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetry (TG) and differential scanning calorimeter (DSC). The ionic conductivity of these novel polymer electrolytes were studied by dielectric-impedance spectroscopy. Li-ion conductivity of these polymer electrolytes depends on the length of the side units as well as the doping ratio. Such electrolytes possess satisfactory ambient temperature ionic conductivity (>10 -4 S cm -1). Cyclic voltammetry results illustrated that the electrochemical stability domain extends over 4 V.

  12. Radiolytic preparation of poly(styrene sulfonic acid) - grafted poly(tetrafluoroethylene- co-perfluorovinyl vinyl ether) membranes with highly cross-linked networks

    NASA Astrophysics Data System (ADS)

    Kang, Sung-A.; Shin, Junhwa; Fei, Geng; Ko, Beom-Seok; Kim, Chong-Yeal; Nho, Young-Chang

    2010-11-01

    In this study, various amounts of a divinylbenzene (DVB) cross-linking agent (5˜30%) were introduced during a simultaneous irradiation grafting of styrene onto a PFA film of a 25 μm thickness in order to prepare a series of poly(styrene sulfonic acid)-grafted poly(tetrafluoroethylene- co-perfluorovinyl vinyl ether) (PFA) membranes with various degrees of cross-linking and grafting (29˜74%). The effects of the DVB cross-linking agent on the properties of the prepared membranes, such as water uptake, proton conductivity, methanol permeability, and chemical stability, were also investigated in this study. The results indicated that the ion exchange capacity (IEC) slightly decreased with increasing DVB content, whereas the water uptake, proton conductivity, and methanol permeability of the membrane greatly decreased. The chemical stability of the prepared membranes was found to be significantly improved with increasing DVB content. The results indicated that the cross-linked network membranes are promising for application in a direct methanol fuel cell.

  13. Aluminum–phthalocyanine chloride associated to poly(methyl vinyl ether-co-maleic anhydride) nanoparticles as a new third-generation photosensitizer for anticancer photodynamic therapy

    PubMed Central

    Muehlmann, Luis Alexandre; Ma, Beatriz Chiyin; Longo, João Paulo Figueiró; Almeida Santos, Maria de Fátima Menezes; Azevedo, Ricardo Bentes

    2014-01-01

    Photodynamic therapy is generally considered to be safer than conventional anticancer therapies, and it is effective against different kinds of cancer. However, its clinical application has been significantly limited by the hydrophobicity of photosensitizers. In this work, a system composed of the hydrophobic photosensitizer aluminum–phthalocyanine chloride (AlPc) associated with water dispersible poly(methyl vinyl ether-co-maleic anhydride) nanoparticles is described. AlPc was associated with nanoparticles produced by a method of solvent displacement. This system was analyzed for its physicochemical characteristics, and for its photodynamic activity in vitro in cancerous (murine mammary carcinoma cell lineage 4T1, and human mammary adenocarcinoma cells MCF-7) and noncancerous (murine fibroblast cell lineage NIH/3T3, and human mammary epithelial cell lineage MCF-10A) cell lines. Cell viability and the elicited mechanisms of cell death were evaluated after the application of photodynamic therapy. This system showed improved photophysical and photochemical properties in aqueous media in comparison to the free photosensitizer, and it was effective against cancerous cells in vitro. PMID:24634582

  14. Computational study on the mechanisms and rate constants of the Cl-initiated oxidation of methyl vinyl ether in the atmosphere.

    PubMed

    Han, Dandan; Cao, Haijie; Li, Mingyue; Li, Xin; Zhang, Shiqing; He, Maoxia; Hu, Jingtian

    2015-01-29

    The Cl-initiated oxidation reactions of methyl vinyl ether (MVE) are analyzed by using the high-level composite method CBS-QB3. Detailed chemistry for the reactions of MVE with chlorine atoms is proposed according to the calculated thermodynamic data. The primary eight channels, including two Cl-addition reactions and six H-abstraction reactions, are discussed. In accordance with the further investigation of the two dominant additional routes, formyl chloride and formaldehyde are the major products. Over the temperature range of 200-400 K and the pressure range of 100-2000 Torr, the rate constants of primary reactions are calculated by employing the MESMER program. H-abstraction channels are negligible according to the value of rate constants. During the studied temperature range, the Arrhenius equation is obtained as ktot = 5.64 × 10(-11) exp(215.1/T). The total rate coefficient is ktot = 1.25 × 10(-10) cm(3) molecule(-1) s(-1) at 298 K and 760 Torr. Finally, the atmospheric lifetime of MVE with respect to Cl is estimated to be 2.23 h. PMID:25565072

  15. Self-assembly behavior of amphiphilic C₆₀-end-capped poly(vinyl ether)s in water and dissociation of the aggregates by the complexing of the C₆₀ moieties with externally added γ-cyclodextrins.

    PubMed

    Motoyanagi, Jin; Kurata, Akihiro; Minoda, Masahiko

    2015-03-01

    C60-end-capped polymers consisting of an amphiphilic poly(2-methoxyethyl vinyl ether) (PMOVE) main chain were synthesized by living cationic polymerization using a C60-functionalized initiator (C60VE-TFA) in the presence of EtAlCl2 as an activator and dioxane as an added base. The obtained polymers (C60-PMOVE) dissolved in a wide range of solvents including water and exhibited solvatochromism depending on the polarity of the media employed. This phenomenon was attributed to self-assembly in polar media due to hydrophobicity of the C60 moieties at the terminus of the amphiphilic polymer chain. Furthermore, the addition of γ-cyclodextrin (γ-CD), a strong host molecule for fullerenes, to the self-assembled system brought about the dissociation of the aggregates into molecularly dispersed free polymer chains. Titration of the aqueous solution of the self-assembly of C60-PMOVE with γ-CD indicated the possible formation of inclusion complexes of C60-PMOVE and γ-CD, and this binding process occurs in a positive cooperative manner. PMID:25658224

  16. Thermo-responsive cell culture carriers based on poly(vinyl methyl ether)—the effect of biomolecular ligands to balance cell adhesion and stimulated detachment

    NASA Astrophysics Data System (ADS)

    Teichmann, Juliane; Nitschke, Mirko; Pette, Dagmar; Valtink, Monika; Gramm, Stefan; Härtel, Frauke V.; Noll, Thomas; Funk, Richard H. W.; Engelmann, Katrin; Werner, Carsten

    2015-08-01

    Two established material systems for thermally stimulated detachment of adherent cells were combined in a cross-linked polymer blend to merge favorable properties. Through this approach poly(N-isopropylacrylamide) (PNiPAAm) with its superior switching characteristic was paired with a poly(vinyl methyl ether)-based composition that allows adjusting physico-chemical and biomolecular properties in a wide range. Beyond pure PNiPAAm, the proposed thermo-responsive coating provides thickness, stiffness and swelling behavior, as well as an apposite density of reactive sites for biomolecular functionalization, as effective tuning parameters to meet specific requirements of a particular cell type regarding initial adhesion and ease of detachment. To illustrate the strength of this approach, the novel cell culture carrier was applied to generate transplantable sheets of human corneal endothelial cells (HCEC). Sheets were grown, detached, and transferred onto planar targets. Cell morphology, viability and functionality were analyzed by immunocytochemistry and determination of transepithelial electrical resistance (TEER) before and after sheet detachment and transfer. HCEC layers showed regular morphology with appropriate TEER. Cells were positive for function-associated marker proteins ZO-1, Na+/K+-ATPase, and paxillin, and extracellular matrix proteins fibronectin, laminin and collagen type IV before and after transfer. Sheet detachment and transfer did not impair cell viability. Subsequently, a potential application in ophthalmology was demonstrated by transplantation onto de-endothelialized porcine corneas in vitro. The novel thermo-responsive cell culture carrier facilitates the generation and transfer of functional HCEC sheets. This paves the way to generate tissue engineered human corneal endothelium as an alternative transplant source for endothelial keratoplasty.

  17. Thermodynamic properties and ideal-gas enthalpies of formation for butyl vinyl ether, 1,2-dimethoxyethane, methyl glycolate, bicyclo[2.2.1]hept-2-ene, 5-vinylbicyclo[2.2.1]hept-2-ene, trans-azobenzene, butyl acrylate, di-tert-butyl ether, and hexane-1,6-diol

    SciTech Connect

    Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Smith, N.K.

    1996-11-01

    Ideal-gas enthalpies of formation of butyl vinyl ether, 1,2-dimethoxyethane, methyl glycolate, bicyclo-[2.2.1]hept-2-ene, 5-vinylbicyclo[2.2.1]hept-2-ene, trans-azobenzene, butyl acrylate, di-tert-butyl ether, and hexane-1,6-diol are reported. Enthalpies of fusion were determined for bicyclo[2.2.1]hept-2-ene and trans-azobenzene. Two-phase (solid + vapor) or (liquid + vapor) heat capacities were determined from 300 K to the critical region or earlier decomposition temperature for each compound studied. Liquid-phase densities along the saturation line were measured for bicyclo[2.2.1]hept-2-ene. For butyl vinyl ether and 1,2-dimethoxyethane, critical temperatures and critical densities were determined from the dsc results and corresponding critical pressures derived from the fitting procedures. Fitting procedures were used to derive critical temperatures, critical pressures, and critical densities for bicyclo[2.2.1]hept-2-ene, 5-vinylbicyclo[2.2.1]hept-2-ene, trans-azobenzene, butyl acrylate, and di-tert-butyl ether. Group-additivity parameters or ring-correction terms useful in the application of the Benson group-contribution correlations were derived.

  18. Acid-labile mPEG-Vinyl Ether-1,2-Dioleylglycerol Lipids with Tunable pH Sensitivity: Synthesis and Structural Effects on Hydrolysis Rates, DOPE Liposome Release Performance and Pharmacokinetics

    PubMed Central

    Shin, Junhwa; Shum, Pochi; Grey, Jessica; Fujiwara, Shin-ichi; Malhotra, Guarov S.; González-Bonet, Andres; Hyun, Seok-Hee; Moase, Elaine; Allen, Theresa M.; Thompson, David H.

    2012-01-01

    A family of 3-methoxypoly(ethylene glycol)-vinyl ether-1,2-dioleylglycerol (mPEG-VE-DOG) lipopolymer conjugates, designed on the basis of DFT calculations to possess a wide range of proton affinities, was synthesized and tested for their hydrolysis kinetics in neutral and acidic buffers. Extruded ~100 nm liposomes containing these constructs in ≥90 mol% 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) produced dispersions that retained their calcein cargo for more than 2 days at pH 7.5, but released the encapsulated contents over a wide range of timescales as a function of the electronic properties of the vinyl ether linkage, the solution pH and the mPEG-VE-DOG composition in the membrane. The in vivo performance of two different 90:10 DOPE:mPEG-VE-DOG compositions was also evaluated for blood circulation time and biodistribution in mice, using 125I-tyraminylinulin as a label. The pharmacokinetic profiles gave a T1/2 of 7 h and 3 h for 90:10 DOPE:ST302 and 90:10 DOPE:ST502, respectively, with the liposomes being cleared predominantly by liver and spleen uptake. The behavior of these DOPE:mPEG-VE-DOG formulations is consistent with their relative rates of vinyl ether hydrolysis, i.e., the more acid-sensitive mPEG-VE-DOG derivatives produce faster leakage rates from DOPE:mPEG-VE-DOG liposomes, but decreased the blood circulation times in mice. These findings suggest that the vinyl ether-based PEG-lipid derivatives are promising agents for stabilizing acid-sensitive DOPE liposomes to produce formulations with a priori control over their pH-responsiveness in vitro. Our data also suggest, however, that the same factors that contribute to enhanced acid-sensitivity of the DOPE:mPEG-VE-DOG dispersions are also likely responsible for their reduced pharmacokinetic profiles. PMID:23030381

  19. Acid-labile mPEG-vinyl ether-1,2-dioleylglycerol lipids with tunable pH sensitivity: synthesis and structural effects on hydrolysis rates, DOPE liposome release performance, and pharmacokinetics.

    PubMed

    Shin, Junhwa; Shum, Pochi; Grey, Jessica; Fujiwara, Shin-ichi; Malhotra, Guarov S; González-Bonet, Andres; Hyun, Seok-Hee; Moase, Elaine; Allen, Theresa M; Thompson, David H

    2012-11-01

    A family of 3-methoxypoly(ethylene glycol)-vinyl ether-1,2-dioleylglycerol (mPEG-VE-DOG) lipopolymer conjugates, designed on the basis of DFT calculations to possess a wide range of proton affinities, was synthesized and tested for their hydrolysis kinetics in neutral and acidic buffers. Extruded ∼100 nm liposomes containing these constructs in ≥90 mol % 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) produced dispersions that retained their calcein cargo for more than 2 days at pH 7.5, but released the encapsulated contents over a wide range of time scales as a function of the electronic properties of the vinyl ether linkage, the solution pH, and the mPEG-VE-DOG composition in the membrane. The in vivo performance of two different 90:10 DOPE:mPEG-VE-DOG compositions was also evaluated for blood circulation time and biodistribution in mice, using (125)I-tyraminylinulin as a label. The pharmacokinetic profiles gave a t(1/2) of 7 and 3 h for 90:10 DOPE:ST302 and 90:10 DOPE:ST502, respectively, with the liposomes being cleared predominantly by liver and spleen uptake. The behavior of these DOPE:mPEG-VE-DOG formulations is consistent with their relative rates of vinyl ether hydrolysis, i.e., the more acid-sensitive mPEG-VE-DOG derivatives produced faster leakage rates from DOPE:mPEG-VE-DOG liposomes, but decreased the blood circulation times in mice. These findings suggest that the vinyl ether-based PEG-lipid derivatives are promising agents for stabilizing acid-sensitive DOPE liposomes to produce formulations with a priori control over their pH responsiveness in vitro. Our data also suggest, however, that the same factors that contribute to enhanced acid sensitivity of the DOPE:mPEG-VE-DOG dispersions are also likely responsible for their reduced pharmacokinetic profiles. PMID:23030381

  20. Comparative evaluation of the metabolic effects of hydroxytyrosol and its lipophilic derivatives (hydroxytyrosyl acetate and ethyl hydroxytyrosyl ether) in hypercholesterolemic rats.

    PubMed

    Tabernero, María; Sarriá, Beatriz; Largo, Carlota; Martínez-López, Sara; Madrona, Andrés; Espartero, José Luis; Bravo, Laura; Mateos, Raquel

    2014-07-25

    Hydroxytyrosol (HT), a virgin olive oil phenolic phytochemical with proven health benefits, has been used to generate new lipophilic antioxidants to preserve fats and oils against autoxidation. The aim of this work is to comparatively evaluate the physiological effects of HT and its lipophilic derivatives, hydroxytyrosyl acetate (HT-Ac) and ethyl hydroxytyrosyl ether (HT-Et), in high-cholesterol fed animals. Male Wistar rats (n = 8) were fed a standard diet (C group), a cholesterol-rich diet (Chol group) or a cholesterol-rich diet supplemented with phenolic compounds (HT group, HT-Ac group and HT-Et group) for 8 weeks. Body and tissue weights, the lipid profile, redox status, and biochemical, hormonal, and inflammatory biomarkers were evaluated. Plasma levels of total cholesterol, LDL cholesterol, glucose, insulin and leptin, as well as malondialdehyde in serum increased in Chol compared to C (p < 0.05). Rats fed the test diets had improved glucose, insulin, leptin and MDA levels and antioxidant capacity status, with HT-Ac being the most effective compound. The studied phenolic compounds also modulated TNF-α and IL-1β plasma levels compared to Chol. HT-Ac and HT-Et improved adipose tissue distribution and adipokine production, decreasing MCP-1 and IL-1β levels. Our results confirm the metabolic effects of HT, which are maintained and even improved by hydrophobic derivatives, particularly HT-Ac. PMID:24855654

  1. No Promoting Effect of Ethyl Tertiary-butyl Ether (ETBE) on Rat Urinary Bladder Carcinogenesis Initiated with N-Butyl-N-(4-hydroxybutyl)nitrosamine

    PubMed Central

    Hagiwara, Akihiro; Imai, Norio; Doi, Yuko; Suguro, Mayuko; Kawabe, Mayumi; Furukawa, Fumio; Nagano, Kasuke; Fukushima, Shoji

    2013-01-01

    The effects of ethyl tertiary-butyl ether (ETBE) on two-stage urinary bladder carcinogenesis in male F344 rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) were investigated at various dose levels with regard to possible promoting activity. Groups of 30 rats were given drinking water containing 500 ppm BBN, as an initiator, for 4 weeks and starting one week thereafter received ETBE by gavage (daily, 7 days/week) at dose levels of 0 (control), 100, 300, 500 or 1000 mg/kg/day until experimental week 36. No statistically significant differences in incidences of preneoplastic lesions, papillomas, and carcinomas of the urinary bladder were evident in rats treated with 100–1000 mg/kg/day ETBE as compared with control values. Furthermore, the average numbers of preneoplastic or neoplastic lesions per unit length of basement membrane in rats given 100–1000 mg/kg/day ETBE were also comparable to control values. However, papillomatosis of the urinary bladder was found in 4 out of 30 rats (13%) in the group given 1000 mg/kg/day ETBE, and soft stones in the urinary bladder were found in 3 out of these 4 rats. The results thus demonstrated that ETBE did not exert promotional activity on urinary bladder carcinogenesis. However, papillomatosis of the urinary bladder developed in small numbers of the rats given ETBE at 1000 mg/kg/day but not in rats given 500 mg/kg/day or lower doses. PMID:24526807

  2. Multifunctional Poly(methyl vinyl ether-co-maleic anhydride)-graft-hydroxypropyl-β-cyclodextrin Amphiphilic Copolymer as an Oral High-Performance Delivery Carrier of Tacrolimus.

    PubMed

    Zhang, Dong; Pan, Xiaolei; Wang, Shang; Zhai, Yinglei; Guan, Jibin; Fu, Qiang; Hao, Xiaoli; Qi, Wanpeng; Wang, Yingli; Lian, He; Liu, Xiaohong; Wang, Yongjun; Sun, Yinghua; He, Zhonggui; Sun, Jin

    2015-07-01

    In order to improve oral bioavailability of tacrolimus (FK506), a novel poly(methyl vinyl ether-co-maleic anhydride)-graft-hydroxypropyl-β-cyclodextrin amphiphilic copolymer (CD-PVM/MA) is developed, combining the bioadhesiveness of PVM/MA, P-glycoprotein (P-gp), and cytochrome P450-inhibitory effect of CD into one. The FK506-loaded nanoparticles (CD-PVM/MA-NPs) were obtained by solvent evaporation method. The physiochemical properties and intestinal absorption mechanism of FK506-loaded CD-PVM/MA-NPs were characterized, and the pharmacokinetic behavior was investigated in rats. FK506-loaded CD-PVM/MA-NPs exhibited nanometer-sized particles of 273.7 nm, with encapsulation efficiency as high as 73.3%. FK506-loaded CD-PVM/MA-NPs maintained structural stability in the simulated gastric fluid, and about 80% FK506 was released within 24 h in the simulated intestinal fluid. The permeability of FK506 was improved dramatically by CD-PVM/MA-NPs compared to its solution, probably due to the synergistic inhibition effect of P-gp and cytochrome P450 3A (CYP3A). The intestinal biodistribution of fluorescence-labeled CD-PVM/MA-NPs confirmed its good bioadhesion to the rat intestinal wall. Two endocytosis pathways, clathrin- and caveolae-mediated endocytosis, were involved in the cellular uptake of CD-PVM/MA-NPs. The important role of lymphatic transport in nanoparticles' access to the systemic circulation, about half of the contribution to oral bioavailability, was observed in mesenteric lymph duct ligated rats. The AUC0-24 of FK506 loaded in nanoparticles was enhanced up to 20-fold compared to FK506 solutions after oral administration. The present study suggested that the novel multifunctional CD-PVM/MA is a promising efficient oral delivery carrier for FK506, due to its ability in solubilization, inhibitory effects on both P-gp and CYP 3A, high bioadhesion, and sustained release capability. PMID:26024817

  3. Rh(I)-catalyzed transformation of propargyl vinyl ethers into (E,Z)-dienals: stereoelectronic role of trans effect in a metal-mediated pericyclic process and a shift from homogeneous to heterogeneous catalysis during a one-pot reaction.

    PubMed

    Vidhani, Dinesh V; Krafft, Marie E; Alabugin, Igor V

    2014-01-01

    The combination of experiments and computations reveals unusual features of stereoselective Rh(I)-catalyzed transformation of propargyl vinyl ethers into (E,Z)-dienals. The first step, the conversion of propargyl vinyl ethers into allene aldehydes, proceeds under homogeneous conditions via a "cyclization-mediated" mechanism initiated by Rh(I) coordination at the alkyne. This path agrees well with the small experimental effects of substituents on the carbinol carbon. The key feature revealed by the computational study is the stereoelectronic effect of the ligand arrangement at the catalytic center. The rearrangement barriers significantly decrease due to the greater transfer of electron density from the catalytic metal center to the CO ligand oriented trans to the alkyne. This effect increases electrophilicity of the metal and lowers the calculated barriers by 9.0 kcal/mol. Subsequent evolution of the catalyst leads to the in situ formation of Rh(I) nanoclusters that catalyze stereoselective tautomerization. The intermediacy of heterogeneous catalysis by nanoclusters was confirmed by mercury poisoning, temperature-dependent sigmoidal kinetic curves, and dynamic light scattering. The combination of experiments and computations suggests that the initially formed allene-aldehyde product assists in the transformation of a homogeneous catalyst (or "a cocktail of catalysts") into nanoclusters, which in turn catalyze and control the stereochemistry of subsequent transformations. PMID:24304338

  4. Spectrometric measurements and DFT studies on new complex of copper (II) with 2-((E)-9-ethyl-3-(2-(6-(4-methylpyridin-2-yl)pyridin-3-yl)vinyl)-9H-carbazole.

    PubMed

    Zhang, Haoyang; Hu, Jie; Zhao, Jianying; Zhang, Yu

    2016-11-01

    The molecular structure of a new complex of copper (II) with (E)-9-ethyl-3-(2-(6-(4-methylpyridin-2-yl)pyridin-3-yl)vinyl)-9H-carbazole ([Cu2(emppc)2Cl2]Cl2) was optimized with B3LYP/LanL2DZ, PBE1PBE/LanL2DZ and M062X/LanL2DZ theoretical level. The ligand, (E)-9-ethyl-3-(2-(6-(4-methylpyridin-2-yl)pyridin-3-yl)vinyl)-9H-carbazole (emppc), binds to Cu(II) ions with a bi-dentate mode, two Cl(-) serve as bridging ligand, each Cu(II) ion has a highly distorted tetrahedron coordination geometry. With M062X/LanL2DZ theoretical level, the calculated interaction energies of Cu(II) with coordination atoms N are between 183.3-200.0kJmol(-1) for α spin and 319.4-324.9kJmol(-1) for β spin, and interaction energies of Cu(II) with coordination atoms Cl atom are 248.0-252.4kJmol(-1) for α spin and 332.6-333.6kJmol(-1) for β spin. The experimental Fourier transform infrared spectrum was assigned. The calculated IR based on B3LYP/LanL2DZ, PBE1PBE/LanL2DZ and M062X/LanL2DZ methods were performed and compared with experimental results. The UV-Vis experimental spectra of [Cu2(emppc)2Cl2]Cl2 was measured in methanol solution. The calculated electronic spectrum was performed with TD/M062X and PCM-TD/M062X methods with LanL2DZ basis set. The nature bond orbital analysis and temperature dependence of the thermodynamic properties were calculated with the same methods. PMID:27285472

  5. Reanalysis of the ground and three torsional excited states of trans-ethyl methyl ether by using an IAM-like tunneling matrix formalism

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kaori; Sakai, Yusuke; Tsunekawa, Shozo; Miyamoto, Taihei; Fujitake, Masaharu; Ohashi, Nobukimi

    2016-03-01

    The trans-ethyl methyl ether has two inequivalent methyl internal rotors and shows tunneling splittings of maximum up to five components. However, the barrier of these two internal rotation potentials were relatively high and the five components were not resolved in the ground state microwave spectra. In this study, well-resolved Fourier transform microwave ground state spectrum was measured for the first time to resolve the five components. The ground state microwave spectra were reanalyzed based on these new measurements and the additional millimeter-wave spectra as well as those studied previously by Fuchs et al. Ninety Fourier transform microwave spectral lines were assigned to 107 transitions in the ground state and 3508 conventional microwave absorption lines were assigned up to Ka = 16 of the ground state, including all 707 lines reported by Fuchs et al. In addition, 10 transitions were observed by the double resonance experiment. They were least-squares-analyzed by the use of an internal axis method (IAM)-like tunneling matrix formalism based on an extended permutation-inversion group theoretical idea. Twenty-two molecular parameters composed of rotational constants, centrifugal distortion constants, internal rotation parameters and internal rotation tunneling parameters were determined for the ground state. The microwave spectra in the three torsionally excited states, that is, the ν28 = 1 C-CH3 torsional state, the ν29 = 1 O-CH3 torsional state and the ν30 = 1 skeletal torsional state, were also reanalyzed by using the IAM-like tunneling matrix formalism and somewhat extended line assignments.

  6. 40 CFR 721.10401 - Oxirane, 2-ethyl-, polymer with oxirane, mono-C11-15-sec-alkyl ethers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oxirane, 2-ethyl-, polymer with... Significant New Uses for Specific Chemical Substances § 721.10401 Oxirane, 2-ethyl-, polymer with oxirane...) The chemical substance identified as oxirane, 2-ethyl-, polymer with oxirane, mono...

  7. 40 CFR 721.10400 - Oxirane, 2-ethyl-, polymer with oxirane, mono-C12-14-sec-alkyl ethers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oxirane, 2-ethyl-, polymer with... Significant New Uses for Specific Chemical Substances § 721.10400 Oxirane, 2-ethyl-, polymer with oxirane...) The chemical substance identified as oxirane, 2-ethyl-, polymer with oxirane,...

  8. Chemistry of enol ethers. LXXXIV. Condensation of acetals of saturated aldehydes with 2-trimethylsilyloxy-1,3-dienes. Synthesis of /beta/-alkoxy-alkyl vinyl and divinyl ketones

    SciTech Connect

    Makin, S.M.; Nazarova, O.N.; Dymshakova, G.M.; Kundryutskova, L.A.

    1988-11-10

    The addition of the acetals of saturated aldehydes (formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, and isobutyraldehyde) to 2-trimethylsilyloxy-4-methyl-1,3-pentadiene in the presence of aprotic acids (ZnCl/sub 2/, ZnBr/sub 2/, FeCl/sub 3/, SnCl/sub 4/, BF/sub 3/ /times/ OEt/sub 2/) takes place at positions 1, 2 of the diene system with the formation of /beta/-alkoxyalkyl vinyl ketones. The most effective catalysts of this reaction were stannic chloride and zinc bromide. The alkyl derivatives of divinyl ketones are formed when the obtained /beta/-alkoxyalkyl vinyl ketones are heated with p-toluenesulfonic acid.

  9. Vinyl stilbazoles

    NASA Technical Reports Server (NTRS)

    Parker, John A. (Inventor); Heimbuch, Alvin H. (Inventor); Hsu, Ming-Ta S. (Inventor); Chen, Timothy S. (Inventor)

    1986-01-01

    Vinyl pyridines including vinyl stilbazole materials and vinyl styrylpyridine oligomer materials are disclosed. These vinylpyridines form copolymers with bismaleimides which copolymers have good fire retardancy and decreased brittleness. The cure temperatures of the copolymers are substantially below the cure temperatures of the bismaleimides alone. Reinforced composites made from the cured copolymers are disclosed as well.

  10. Characterization of the interaction between two food aroma components, alpha-pinene and ethyl butyrate, and ethylene-vinyl alcohol copolymer (EVOH) packaging films as a function of environmental humidity.

    PubMed

    López-Carballo, Gracia; Cava, David; Lagarón, Jose M; Catalá, Ramón; Gavara, Rafael

    2005-09-01

    The ethylene-vinyl alcohol copolymers (EVOHs) are well-known high oxygen barrier materials that are being used successfully in the design of packaging structures for oxygen-sensitive food or pharmaceutical products. Recently, there has been increasing interest in using EVOH materials to provide a high barrier to organic compounds as a means to reduce food aroma scalping. However, the barrier function of this family of materials diminishes significantly in humid environments, and it is supposed that so does the organic vapor barrier. In this work, a new sorption-based method to characterize the interaction between food aroma and polymer films for packaging as a function of relative humidity is presented and is used to determine the barrier to ethyl butyrate and alpha-pinene of EVOH at 23 degrees C. The results show that although EVOH is an excellent barrier to food aroma when dry, a property that even improves at low relative humidity (RH), the solubility and diffusivity of the compounds tested increase dramatically with humidity at medium to high water activities. However, even in the worst case (100% RH), EVOH outperforms low-density polyethylene (LDPE) as a barrier to organic vapors at least 500,000-fold. PMID:16131132

  11. Ether modifications to 1-[2-(3,4-dimethoxyphenyl)ethyl]-4-(3-phenylpropyl)piperazine (SA4503): effects on binding affinity and selectivity for sigma receptors and monoamine transporters

    PubMed Central

    Xu, Rong; Lord, Sarah A.; Peterson, Ryan M.; Fergason-Cantrell, Emily A.; Lever, John R.; Lever, Susan Z.

    2014-01-01

    Two series of novel ether analogs of the sigma (σ) receptor ligand 1-[2-(3,4-dimethoxyphenyl)ethyl]-4-(3-phenylpropyl)piperazine (SA4503) have been prepared. In one series, the alkyl portion of the 4-methoxy group was replaced with allyl, propyl, bromoethyl, benzyl, phenethyl, and phenylpropyl moieties. In the second series, the 3,4-dimethoxy was replaced with cyclic methylenedioxy, ethylenedioxy and propylenedioxy groups. These ligands, along with 4-O-des-methyl SA4503, were evaluated for σ1 and σ2 receptor affinity, and compared to SA4503 and several known ether analogs. SA4503 and a subset of ether analogs were also evaluated for dopamine transporter (DAT) and serotonin transporter (SERT) affinity. The highest σ1 receptor affinities, Ki values of 1.75 nM – 4.63 nM, were observed for 4-O-des-methyl SA4503, SA4503 and the methylenedioxy analog. As steric bulk increased, σ1 receptor affinity decreased, but only to a point. Allyl, propyl and bromoethyl substitutions gave σ1 receptor Ki values in the 20 nM – 30 nM range, while bulkier analogs having phenylalkyl, and Z- and E-iodoallyl, ether substitutions showed higher σ1 affinities, with Ki values in the 13 nM – 21 nM range. Most ligands studied exhibited comparable σ1 and σ2 affinities, resulting in little to no subtype selectivity. SA4503, the fluoroethyl analog and the methylenedioxy congener showed modest six- to fourteen-fold selectivity for σ1 sites. DAT and SERT interactions proved much more sensitive than σ receptor interactions to these structural modifications. For example, the benzyl congener (σ1 Ki = 20.8 nM; σ2 Ki = 16.4 nM) showed over 100-fold higher DAT affinity (Ki = 121 nM) and 6-fold higher SERT affinity (Ki = 128 nM) than the parent SA4503 (DAT Ki = 12650 nM; SERT Ki = 760 nM). Thus, ether modifications to the SA4503 scaffold can provide polyfunctional ligands having a broader spectrum of possible pharmacological actions. PMID:25468036

  12. The Search for a Complex Molecule in a Selected Hot Core Region: a Rigorous Attempt to Confirm Trans-Ethyl Methyl Ether Toward W51 E1/E2

    NASA Astrophysics Data System (ADS)

    Carroll, Brandon; McGuire, Brett A.; Apponi, Aldo J.; Ziurys, Lucy; Blake, Geoffrey; Remijan, Anthony

    2014-06-01

    An extensive search has been conducted to confirm transitions of trans-ethyl methyl ether (tEME), (C_2H_5OCH_3), toward the high mass star forming region W51 e1/e2 using the 12 m Telescope of the Arizona Radio Observatory (ARO) at 2 mm and 3 mm wavelengths. Typical peak to peak noise levels for the present observations of W51e1/e2 were between 10 mK to 30 mK, indicating an upper limit of the tEME column density of ≤ 1.5 × 1015 cm-2, this would make tEME at least a factor 2 times less abundant than dimethyl ether (CH_3OCH_3) toward W51 e1/e2. We have also performed an extensive search for this species toward the high mass star forming region Sgr B2(N-LMH) with the NRAO 100 m Green Bank Telescope (GBT). No transitions of tEME were detected and we were able to set an upper limit to the tEME column density of ≤ 4 × 1014 cm-2 toward Sgr B2(N-LMH). We will discuss these observations in the context of detecting large complex organic species toward star forming regions with next generation telescopes such as ALMA.

  13. Combined /sup 2/H and /sup 18/O isotope effects in support of a concerted, synchronous elimination of acetaldehyde from a bis(benzyl ethyl ether) radical cation

    SciTech Connect

    Allison, C.E.; Stringer, M.B.; Bowie, J.H.; Derrick, P.J.

    1988-09-14

    No evidence has been found of hydrogen scrambling accompanying decomposition of the benzyl ether molecular ion at times approaching 100 ..mu..s. Isotope effects upon produce ion abundances have been measured for elimination of acetaldehyde from the molecular ions of multiply labeled diethoxyxylenes and compared with the results of calculations of kinetic isotope effects using the quasi-equilibrium theory. It is concluded that this rearrangement involving a 6-membered cyclic transition state can be described as a concerted, synchronous process. 31 references, 7 figures, 1 table.

  14. DIPPR Project 871 For 1995 - Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for Methyl Benzoate, Ethyl Benzoate, (R)-(+)-Limonene, Tert-Amyl Methyl Ether, Trans-Crotonaldehyde, and

    SciTech Connect

    Steele, W.V.

    2002-07-01

    Ideal-gas enthalpies of formation of methyl benzoate, ethyl benzoate, (R)-(+)-limonene, tert-amyl methyl ether, trans-crotonaldehyde, and diethylene glycol are reported. The standard energy of combustion and hence standard enthalpy of formation of each compound in the liquid phase has been measured using an oxygen rotating-bomb calorimeter without rotation. Vapor pressures were measured to a pressure limit of 270 kPa or the lower decomposition point for each of the six compounds using a twin ebulliometric apparatus. Liquid-phase densities along the saturation line were measured for each compound over a range of temperature (ambient to a maximum of 548 K). A differential scanning calorimeter was used to measure two-phase (liquid + vapor) heat capacities for each compound in the temperature region ambient to the critical temperature or lower decomposition point. For methyl benzoate and tert-amyl methyl ether, critical temperatures and critical densities were determined from the DSC results and corresponding critical pressures derived from the fitting procedures. Fitting procedures were used to derive critical temperatures, critical pressures, and critical densities for each of the remaining compounds. The results of the measurements were combined to derive a series of thermophysical properties including critical temperature, critical density, critical pressure, acentric factor, enthalpies of vaporization (restricted to within {+-}50 K of the temperature region of the experimentally determined vapor pressures), and heat capacities along the saturation line. Wagner-type vapor-pressure equations were derived for each compound. All measured and derived values were compared with those obtained in a search of the literature. Recommended critical parameters are listed for each of the compounds studied. Group-additivity parameters, useful in the application of the Benson gas-phase group-contribution correlations, were derived.

  15. The Search for a Complex Molecule in a Selected Hot Core Region: A Rigorous Attempt to Confirm Trans-ethyl Methyl Ether toward W51 e1/e2

    NASA Astrophysics Data System (ADS)

    Carroll, P. Brandon; McGuire, Brett A.; Blake, Geoffrey A.; Apponi, A. J.; Ziurys, L. M.; Remijan, Anthony

    2015-01-01

    An extensive search has been conducted to confirm transitions of trans-ethyl methyl ether (tEME, C2H5OCH3), toward the high-mass star forming region W51 e1/e2 using the 12 m Telescope of the Arizona Radio Observatory at wavelengths from 2 mm and 3 mm. In short, we cannot confirm the detection of tEME toward W51 e1/e2 and our results call into question the initial identification of this species by Fuchs et al. Additionally, re-evaluation of the data from the original detection indicates that tEME is not present toward W51 e1/e2 in the abundance reported by Fuchs and colleagues. Typical peak-to-peak noise levels for the present observations of W51 e1/e2 were between 10 and 30 mK, yielding an upper limit of the tEME column density of <=1.5 × 1015 cm-2. This would make tEME at least a factor of two times less abundant than dimethyl ether (CH3OCH3) toward W51 e1/e2. We also performed an extensive search for this species toward the high-mass star forming region Sgr B2(N-LMH) with the National Radio Astronomy Observatory 100 m Green Bank Telescope. No transitions of tEME were detected and we were able to set an upper limit to the tEME column density of <=4 × 1014 cm-2 toward this source. Thus, we are able to show that tEME is not a new molecular component of the interstellar medium and that an exacting assessment must be carried out when assigning transitions of new molecular species to astronomical spectra to support the identification of large organic interstellar molecules.

  16. Fabrication and characterization of superparamagnetic and thermoresponsive hydrogels based on oleic-acid-coated Fe 3O 4 nanoparticles, hexa(ethylene glycol) methyl ether methacrylate and 2-(acetoacetoxy)ethyl methacrylate

    NASA Astrophysics Data System (ADS)

    Papaphilippou, Petri C.; Pourgouris, Antonis; Marinica, Oana; Taculescu, Alina; Athanasopoulos, George I.; Vekas, Ladislau; Krasia-Christoforou, Theodora

    2011-03-01

    Stimuli-responsive hydrogel nanocomposites comprised of swollen polymer networks, in which magnetic nanoparticles are embedded, are a relatively new class of "smart" soft materials presenting a significant impact on various technological and biomedical applications. A novel approach for the fabrication of hydrogel nanocomposites exhibiting temperature- and magneto-responsive behavior involves the random copolymerization of hexa(ethylene glycol) methyl ether methacrylate (HEGMA, hydrophilic, thermoresponsive) and 2-(acetoacetoxy)ethyl methacrylate (AEMA, hydrophobic, metal-chelating) in the presence of preformed oleic-acid-coated magnetite nanoparticles (OA·Fe 3O 4). In total, two series of hydrogel nanocomposites have been prepared in two different solvent systems: ethyl acetate (series A) and tetrahydrofuran (series B). The degrees of swelling (DSs) of all conetworks were determined in organic and in aqueous media. The nanocrystalline phase adopted by the embedded magnetic nanoparticles was investigated by X-ray diffraction (XRD) spectroscopy. The obtained diffraction patterns indicated the presence of magnetite (Fe 3O 4). Deswelling kinetic studies that were carried out at ˜60 °C in water demonstrated the thermoresponsive properties of the hydrogel nanocomposites, attributed to the presence of the hexaethylene glycol side chains within the conetworks. Moreover, thermal gravimetric analysis (TGA) measurements showed that these materials exhibited superior thermal stability compared to the pristine hydrogels. Further to the characterization of compositional and thermal properties, the assessment of magnetic characteristics by vibrational sample magnetometry (VSM) disclosed superparamagnetic behavior. The tunable superparamagnetic behavior exhibited by these materials depending on the amount of magnetic nanoparticles incorporated within the networks combined with their thermoresponsive properties may allow for their future exploitation in the biomedical field.

  17. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether...

  18. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether...

  19. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether...

  20. Comparison of removal of endodontic smear layer using ethylene glycol bis (beta-amino ethyl ether)-N, N, N', N'-tetraacetic acid and citric acid in primary teeth: A scanning electron microscopic study

    PubMed Central

    Hegde, Rahul J.; Bapna, Kavita

    2016-01-01

    Background: Root canal irrigants are considered momentous in their tissue dissolving property, eliminating microorganisms, and removing smear layer. The present study was aimed to compare the removal of endodontic smear layer using ethylene glycol bis (beta-amino ethyl ether)-N, N, N', N'-tetraacetic acid (EGTA) and citric acid solutions with saline as a control in primary anterior teeth. Materials and Methods: Thirty primary anterior teeth were chosen for the study. The teeth were distributed into three groups having ten teeth each. Following instrumentation, root canals of the first group were treated with 17% EGTA and the second group with 6% citric acid. Only saline was used as an irrigant for the control group. Then, the teeth were subjected to scanning electron microscopy (SEM) study. The scale given by Rome et al. for the smear layer removal was used in the present study. Results: The pictures from the SEM showed that among the tested irrigants, 17% EGTA + 5% sodium hypochlorite (NaOCl) group showed the best results when compared to other groups. Conclusion: The results advocate that the sequential irrigation of the pulp canal walls with 17% EGTA followed by 5% NaOCl produced efficacious and smear-free root canal walls. PMID:27307670

  1. Vinyl chloride

    Integrated Risk Information System (IRIS)

    Vinyl chloride ; CASRN 75 - 01 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  2. Vinyl acetate

    Integrated Risk Information System (IRIS)

    Vinyl acetate ; CASRN 108 - 05 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  3. Vinyl bromide

    Integrated Risk Information System (IRIS)

    Vinyl bromide ; CASRN 593 - 60 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  4. Chemistry of enol ethers. LXXXIII. Synthesis and investigation of penta- and hexacarbocyanine dyes containing cyclic fragments in the polymethine chain

    SciTech Connect

    Makin, S.M.; Shavrygina, O.A.; Boiko, T.N.; Monich, N.V.; Pomogaev, A.I.

    1988-09-20

    4,6-Dimethylene- and 4,6-trimethylene-1,1,3,7,9-4,8-nonadienes were obtained by the reaction of 2,4-dimethylene- and 2,4-trimethylene-1,1,5,7-tetraethoxy-2,6-heptadienes with vinyl ethyl ether. Treatment of the products with N-methylaniline in an acidic medium gave the corresponding nonamethine salts. Condensation of the latter with 2-methyl-3-ethylbenzothiazolium iodide led to thiapentacarbocyanine dyes having symmetrically arranged di- and trimethylene bridges between the meta atoms of the polymethine chain. The reaction of glutaconaldehyde acetal with the cyclic 1-alkoxy-1,3-dienes led to the synthesis of 2,4-dimethylene- and 2,4-trimethylene-1,1,5,9,9-pentaalkoxy-2,6-nonadienes, from the thiapentacarbocyanines with an unsymmetrical arrangement of the dimethylene and trimethylene bridges were obtained through the respective nonamethine salts. A thiahexacarbocyanine dye containing a trimethylene bridge was synthesized from the undercamethine salt obtained from the product from the reaction of 1,1,5,9,9-pentamethoxy-2,4-trimethylene-2,6-nonadiene with vinyl ethyl ether.

  5. THE SEARCH FOR A COMPLEX MOLECULE IN A SELECTED HOT CORE REGION: A RIGOROUS ATTEMPT TO CONFIRM TRANS-ETHYL METHYL ETHER TOWARD W51 e1/e2

    SciTech Connect

    Carroll, P. Brandon; McGuire, Brett A.; Blake, Geoffrey A.; Apponi, A. J.; Ziurys, L. M.; Remijan, Anthony

    2015-01-20

    An extensive search has been conducted to confirm transitions of trans-ethyl methyl ether (tEME, C{sub 2}H{sub 5}OCH{sub 3}), toward the high-mass star forming region W51 e1/e2 using the 12 m Telescope of the Arizona Radio Observatory at wavelengths from 2 mm and 3 mm. In short, we cannot confirm the detection of tEME toward W51 e1/e2 and our results call into question the initial identification of this species by Fuchs et al. Additionally, re-evaluation of the data from the original detection indicates that tEME is not present toward W51 e1/e2 in the abundance reported by Fuchs and colleagues. Typical peak-to-peak noise levels for the present observations of W51 e1/e2 were between 10 and 30 mK, yielding an upper limit of the tEME column density of ≤1.5 × 10{sup 15} cm{sup –2}. This would make tEME at least a factor of two times less abundant than dimethyl ether (CH{sub 3}OCH{sub 3}) toward W51 e1/e2. We also performed an extensive search for this species toward the high-mass star forming region Sgr B2(N-LMH) with the National Radio Astronomy Observatory 100 m Green Bank Telescope. No transitions of tEME were detected and we were able to set an upper limit to the tEME column density of ≤4 × 10{sup 14} cm{sup –2} toward this source. Thus, we are able to show that tEME is not a new molecular component of the interstellar medium and that an exacting assessment must be carried out when assigning transitions of new molecular species to astronomical spectra to support the identification of large organic interstellar molecules.

  6. Allene ether Nazarov cyclization.

    PubMed

    Tius, Marcus A

    2014-05-01

    The ease of synthesis and the exceptional reactivity of alkoxyallenes has led to their use in a large number of highly diverse applications. This Report describes their use in various versions of the allene ether Nazarov cyclization. Following a brief introduction to the Nazarov cyclization (Section 1), the oxidative cyclization of vinyl alkoxyallenes is discussed first (Section 2). Nazarov cyclizations of α-alkoxyallenyl vinyl ketones and of α-alkoxyallenyl vinyl tertiary carbinols are covered (Section 3). The discovery and the subsequent rational design of acetals that serve as chiral auxiliaries on the allene in highly enantioselective Nazarov cyclizations is explained (Section 4). Interrupted Nazarov cyclizations of alkoxyallenes that are generated in situ from the isomerization of propargyl ethers on solid supports are discussed, including the evolution of a highly diastereoselective, chiral auxiliary controlled version of the reaction. Some applications of the methodology to natural products total synthesis have been included so as to provide the reader with benchmarks with which to judge the utility of the methodology. PMID:24196585

  7. Formation of secondary organic aerosol and oligomers from the ozonolysis of enol ethers

    NASA Astrophysics Data System (ADS)

    Sadezky, A.; Chaimbault, P.; Mellouki, A.; Römpp, A.; Winterhalter, R.; Le Bras, G.; Moortgat, G. K.

    2006-06-01

    Formation of secondary organic aerosol has been observed in the gas phase ozonolysis of a series of enol ethers, among them several alkyl vinyl ethers (AVE, ROCH=CH2), such as ethyl, propyl, n-butyl, iso-butyl, t-butyl vinyl ether, and ethyl propenyl ether (EPE, C2H5OCH=CHCH3). The ozonolysis has been studied in a 570 l spherical glass reactor at atmospheric pressure (730 Torr) and temperature (296 K). Gas phase reaction products were investigated by in-situ FTIR spectroscopy, and secondary organic aerosol (SOA) formation was monitored by a scanning mobility particle sizer (SMPS). The chemical composition of the formed SOA was analysed by a hybrid mass spectrometer using electrospray ionization (ESI). The main stable gas phase reaction product is the respective alkyl formate ROC(O)H, formed with yields of 60 to 80%, implying that similar yields of the corresponding Criegee Intermediates (CI) CH2O2 for the AVE and CH3CHO2 for EPE are generated. Measured SOA yields are between 2 to 4% for all enol ethers. Furthermore, SOA formation is strongly reduced or suppressed by the presence of an excess of formic acid, which acts as an efficient CI scavenger. Chemical analysis of the formed SOA by ESI(+)/MS-TOF allows to identify oligomeric compounds in the mass range 200 to 800 u as its major constituents. Repetitive chain units are identified as CH2O2 (mass 46) for the AVE and C2H4O2 (mass 60) for EPE and thus have the same chemical compositions as the respective major Criegee Intermediates formed during ozonolysis of these ethers. The oligomeric structure and chain unit identity are confirmed by HPLC/ESI(+)/MS-TOF and ESI(+)/MS/MS-TOF experiments, whereby successive and systematic loss of a fragment with mass 46 for the AVE (and mass 60 for EPE) is observed. It is proposed that the oligomer has the following basic structure of an oligoperoxide, -[CH(R)-O-O]n-, where R=H for the AVE and R=CH3 for the EPE. Oligoperoxide formation is thus suggested to be another, so far

  8. Formation of secondary organic aerosol and oligomers from the ozonolysis of enol ethers

    NASA Astrophysics Data System (ADS)

    Sadezky, A.; Chaimbault, P.; Mellouki, A.; Römpp, A.; Winterhalter, R.; Le Bras, G.; Moortgat, G. K.

    2006-10-01

    Formation of secondary organic aerosol has been observed in the gas phase ozonolysis of a series of enol ethers, among them several alkyl vinyl ethers (AVE, ROCH=CH2), such as ethyl, propyl, n-butyl, iso-butyl, t-butyl vinyl ether, and ethyl propenyl ether (EPE, C2H5OCH=CHCH3). The ozonolysis has been studied in a 570 l spherical glass reactor at ambient pressure (730 Torr) and room temperature (296 K). Gas phase reaction products were investigated by in-situ FTIR spectroscopy, and secondary organic aerosol (SOA) formation was monitored by a scanning mobility particle sizer (SMPS). The chemical composition of the formed SOA was analysed by a hybrid mass spectrometer using electrospray ionization (ESI). The main stable gas phase reaction product is the respective alkyl formate ROC(O)H, formed with yields of 60 to 80%, implying that similar yields of the corresponding excited Criegee Intermediates (CI) CH2O2 for the AVE and CH3CHO2 for EPE are generated. Measured SOA yields are between 2 to 4% for all enol ethers. Furthermore, SOA formation is strongly reduced or suppressed by the presence of an excess of formic acid, which acts as an efficient CI scavenger. Chemical analysis of the formed SOA by ESI(+)/MS-TOF allows to identify oligomeric compounds in the mass range 200 to 800 u as its major constituents. Repetitive chain units are identified as CH2O2 (mass 46) for the AVE and C2H4O2 (mass 60) for EPE and thus have the same chemical compositions as the respective major Criegee Intermediates formed during ozonolysis of these ethers. The oligomeric structure and chain unit identity are confirmed by HPLC/ESI(+)/MS-TOF and ESI(+)/MS/MS-TOF experiments, whereby successive and systematic loss of a fragment with mass 46 for the AVE (and mass 60 for EPE) is observed. It is proposed that the oligomer has the following basic structure of an oligoperoxide, -[CH(R)-O-O]n-, where R=H for the AVE and R=CH3 for the EPE. Oligoperoxide formation is thus suggested to be another, so

  9. Reactions involving shifting of the double bond in cyclic ethers

    SciTech Connect

    Ibatullin, U.G.; Petrushina, T.F.; Akhmadeeva, A.A.; Safarov, M.G.

    1985-09-01

    4-Methylenetetrahydropyran undergoes isomerization to 4-methyl-5,6-dihydropyran in the presence of sodium on aluminum oxide. Both pyrans are converted to a vinyl ether, viz., 4-methyl-2,3-dihydropyran, under the influence of iron pentacarbonyl.

  10. Icosapent Ethyl

    MedlinePlus

    ... weight loss, exercise) to reduce the amount of triglycerides (a fat-like substance) in your blood. Icosapent ... ethyl may work by decreasing the amount of triglycerides and other fats made in the liver.

  11. Mode of action of ethyl tertiary-butyl ether hepatotumorigenicity in the rat: Evidence for a role of oxidative stress via activation of CAR, PXR and PPAR signaling pathways

    SciTech Connect

    Kakehashi, Anna; Hagiwara, Akihiro; Imai, Norio; Nagano, Kasuke; Nishimaki, Fukumi; Banton, Marcy; Fukushima, Shoji; Wanibuchi, Hideki

    2013-12-01

    To elucidate possible mode of action (MOA) and human relevance of hepatotumorigenicity in rats for ethyl tertiary-butyl ether (ETBE), male F344 rats were administered ETBE at doses of 0, 150 and 1000 mg/kg body weight twice a day by gavage for 1 and 2 weeks. For comparison, non-genotoxic carcinogen phenobarbital (PB) was applied at a dose of 500 ppm in diet. Significant increase of P450 total content and hydroxyl radical levels by low, high doses of ETBE and PB treatments at weeks 1 and 2, and 8-OHdG formation at week 2, accompanied accumulation of CYP2B1/2B2, CYP3A1/3A2 and CYP2C6, and downregulation of DNA oxoguanine glycosylase 1, induction of apoptosis and cell cycle arrest in hepatocytes, respectively. Up-regulation of CYP2E1 and CYP1A1 at weeks 1 and 2, and peroxisome proliferation at week 2 were found in high dose ETBE group. Results of proteome analysis predicted activation of upstream regulators of gene expression altered by ETBE including constitutive androstane receptor (CAR), pregnane-X-receptor (PXR) and peroxisome proliferator-activated receptors (PPARs). These results indicate that the MOA of ETBE hepatotumorigenicity in rats may be related to induction of oxidative stress, 8-OHdG formation, subsequent cell cycle arrest, and apoptosis, suggesting regenerative cell proliferation after week 2, predominantly via activation of CAR and PXR nuclear receptors by a mechanism similar to that of PB, and differentially by activation of PPARs. The MOA for ETBE hepatotumorigenicity in rats is unlikely to be relevant to humans. - Highlights: • We focus on MOA and human relevance of hepatotumorigenicity in rats for ETBE. • ETBE was administered to F344 rats for 1 and 2 weeks. • Oxidative stress formation, proliferation and apoptosis in the liver are analyzed. • ETBE-induced changes of gene and protein expression in the liver are examined. • The effects are compared with those induced by non-genotoxic carcinogen PB.

  12. Reactivity of vinyl phosphonate containing diazoesters: formation, reactivity, and utility.

    PubMed

    Wang, Jin; Rainier, Jon D

    2015-01-16

    Treatment of diazo vinyl phosphonate with alcohols, amines, and thiols in the presence of Rh(II) results in the chemo- and stereoselective generation of enol ethers, enamines and vinyl sulfides via an X-H insertion process. The utility of the products from these reactions was demonstrated through their conversion into quaternary substituted heterocycles including furans and oxetanes as highlighted by the generation of a bicyclic phosphonate analogue of neodysiherbaine. PMID:25534147

  13. Preparation of hydrophilic vinyl chloride copolymer hollow fiber membranes with antifouling properties

    NASA Astrophysics Data System (ADS)

    Rajabzadeh, Saeid; Sano, Rie; Ishigami, Toru; Kakihana, Yuriko; Ohmukai, Yoshikage; Matsuyama, Hideto

    2015-01-01

    Hydrophilic vinyl chloride copolymer hollow fiber membranes with antifouling properties were prepared from brominated vinyl chloride-hydroxyethyl methacrylate copolymer (poly(VC-co-HEMA-Br)). The base membrane was grafted with two different zwitterionic monomers, (2-methacryloyloxyethylphosphorylcholine) (MPC) and [2-(methacryloyloxy) ethyl] dimethyl (3-sulfopropyl) ammonium hydroxide) (MEDSAH), and poly(ethylene glycol) methyl ether methacrylate (PEGMA). The effect of the grafting on the base membrane hydrophilicity and antifouling properties was investigated. For comparison of the results, the pure water permeabilities and pore sizes at the outer surfaces of the grafted hollow fiber membranes were controlled to be similar. A poly(VC-co-HEMA-Br) hollow fiber membrane with similar pure water permeability and pore size was also prepared as a control membrane. A BSA solution was used as a model fouling solution for evaluation of the antifouling properties. Grafting with zwitterionic monomers and PEGMA improved the antifouling properties compared with the control membrane. The PEGMA grafted membrane showed the best antifouling properties among the grafted membranes

  14. Ethyl carbamate

    Integrated Risk Information System (IRIS)

    Ethyl carbamate ; CASRN 51 - 79 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  15. Ethyl chloride

    Integrated Risk Information System (IRIS)

    Ethyl chloride ; CASRN 75 - 00 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  16. Ethyl acetate

    Integrated Risk Information System (IRIS)

    Ethyl acetate ; CASRN 141 - 78 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  17. Obstetric and Other Uses of Ether Before Ether Day, According to the Boston Medical and Surgical Journal of 1828-1846.

    PubMed

    Stoller, Sundrayah N; Minehart, Rebecca D; Alston, Theodore A

    2016-04-01

    From the inception of the Boston Medical and Surgical Journal in 1828 until the prominent public demonstration of surgical anesthesia on Ether Day of 1846, ether was often mentioned in the journal. Many of the examples were related to obstetrics. Because molecular structures were not available in the early 1800s, diverse volatile liquids were termed ethers. In addition to sulphuric ether, so-called ethers included cyanide-releasing propionitrile and ethanolic solutions of chloroform and of the potent vasodilator ethyl nitrite. Familiarity with anesthetically unsuitable ethers may have long deterred consideration of inhaled sulphuric ether for analgesia and anesthesia. PMID:27080505

  18. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1990-01-01

    Polyimide resins having improved thermo-oxidative stability are provided having aromatic vinyl end-caps. The polyimides are prepared by the reaction of a mixture of monomers comprising (1) a diamine, (2) an ester of tetracarboxylic acid and (3) an aromatic vinyl compound in a molar ratio of 1:2:3 of n: (n + 1):2 when the aromatic vinyl compound contains nitrogen and in a ratio of (n + 1):n:2 when the aromatic vinyl compound does not contain nitrogen, wherein n ranges from about 5 to about 20.

  19. Nickel-Catalyzed Intramolecular C-O Bond Formation: Synthesis of Cyclic Enol Ethers.

    PubMed

    Han, Seo-Jung; Doi, Ryohei; Stoltz, Brian M

    2016-06-20

    An efficient and exceptionally mild intramolecular nickel-catalyzed carbon-oxygen bond-forming reaction between vinyl halides and primary, secondary, and tertiary alcohols has been achieved. Zinc powder was found to be an essential additive for obtaining high catalyst turnover and yields. This operationally simple method allows direct access to cyclic vinyl ethers in high yields in a single step. PMID:27159831

  20. Preparation of vinyl acetate

    DOEpatents

    Tustin, Gerald Charles; Zoeller, Joseph Robert; Depew, Leslie Sharon

    1998-01-01

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  1. Preparation of vinyl acetate

    DOEpatents

    Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

    1998-03-24

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  2. Pentabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Pentabromodiphenyl ether ; CASRN 32534 - 81 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  3. Hexabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Hexabromodiphenyl ether ; CASRN 36483 - 60 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  4. Tetrabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Tetrabromodiphenyl ether ; CASRN 40088 - 47 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  5. Nonabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Nonabromodiphenyl ether ; CASRN 63936 - 56 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  6. Tribromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Tribromodiphenyl ether ; CASRN 49690 - 94 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  7. Octabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Octabromodiphenyl ether ; CASRN 32536 - 52 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  8. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ethyl alcohol containing ethyl acetate....

  9. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ethyl alcohol containing ethyl acetate....

  10. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ethyl alcohol containing ethyl acetate....

  11. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ethyl alcohol containing ethyl acetate....

  12. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ethyl alcohol containing ethyl acetate....

  13. Labeled 1,N6-ethenoadenosine and 3,N4-ethenocytidine in hepatic RNA of mice given[ethyl-1,2(-3)H or ethyl-1(-14)C]ethyl carbamate (urethan).

    PubMed

    Ribovich, M L; Miller, J A; Miller, E C; Timmins, L G

    1982-01-01

    Injection of a single dose of[ethyl-1,2(-3)H]or[ethyl-1(-14C]- ethyl carbamate into 12-day old male[C57BL/6 x C3H/He]F1 mice or of[ethyl-1,2(-3H]ethyl carbamate into adult male A/Jax mice resulted in the formation of labeled 1,N6-ethenoadenosine and 3,N4-ethenocytidine adducts in the hepatic RNA. These adducts were characterized by comigration on h.p.l.c. of 3H or 14C in enzymatic hydrolysates of the RNA with synthetic standards. Both the ethenoadenosine and ethenocytidine were further characterized by their conversion to acetylated products that comigrated with acetylated synthetic standards. The ethenoadenosine was also converted by anhydrous trifluoroacetic acid to a product that comigrated with synthetic 1,N6-ethenoadenine. The levels of adducts in the hepatic RNA 12 h after a single injection of 0.5-0.6 mg of ethyl carbamate/g body weight were 6-10 and 2-3 pmol/mg RNA of ethenoadenosine and ethenocytidine, respectively. No labeled ethenoadenosine or ethenocytidine could be detected in the hepatic RNA of mice given[1-14C]ethanol, an enzymatic hydrolysis product of ethyl carbamate. These data indicate that ethyl carbamate may be metabolically activated by dehydrogenation to vinyl carbamate and subsequent epoxidation of the latter compound as previously proposed. Vinyl carbamate epoxide may form etheno derivatives in a manner analogous to that demonstrated for chloroethylene oxide, an electrophilic metabolite of vinyl chloride. Vinyl carbamate has been shown to have the same spectrum of tumor induction as ethyl carbamate but to be much more active than the latter carcinogen. PMID:6178529

  14. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  15. Elucidation of the preferred routes of C8-vinyl reduction in chlorophyll and bacteriochlorophyll biosynthesis

    PubMed Central

    Canniffe, Daniel P.; Chidgey, Jack W.; Hunter, C. Neil

    2014-01-01

    Most of the chlorophylls and bacteriochlorophylls utilized for light harvesting by phototrophic organisms carry an ethyl group at the C8 position of the molecule, the product of a C8-vinyl reductase acting on a chlorophyll/bacteriochlorophyll biosynthetic precursor. Two unrelated classes of C8-vinyl reductase are known to exist, BciA and BciB, found in the purple phototroph Rhodobacter sphaeroides and the cyanobacterium Synechocystis sp. PCC6803 respectively. We constructed strains of each bacterium with the native C8-vinyl reductase swapped for the other class of the enzyme, and combined these replacements with a series of deletions of the native bch and chl genes. In vivo data indicate that the preferred substrates for both classes of the enzyme is C8-vinyl chlorophyllide, with C8-vinyl protochlorophyllide reduced only under conditions in which this pigment accumulates as a result of perturbed formation of chlorophyllide. PMID:24942864

  16. The direct polymerization of vinyl alcohol and vinyl alcohol derivatives

    SciTech Connect

    Novak, B.M.; Cederstav, A.K.

    1995-12-01

    The copolymerization of vinyl alcohol with a number of electron deficient olefins is reported. Vinyl alcohol was formed through the acid catalyzed hydrolysis of ketene methyl vinyl acetal. Under water starved conditions, the kinetics of tautomerization have a zero order dependence upon the concentration of vinyl alcohol (k{sub obs} = 3.5 x 10{sup -6} M/s). Hence, under these conditions, the half life of vinyl alcohol can be several hours at room temperature. We found that this meta-stable species could be quantitatively polymerized in a copolymerization (AIBN, h{upsilon}, -10 to 25{degrees}C) with maleic anhydride, maleimide or acrylonitrile.

  17. Vintage Vinyl Record Design

    ERIC Educational Resources Information Center

    Sacco, Michael

    2008-01-01

    In this article, the author describes a project in which his ninth-grade art students utilized a vinyl record as an unusual medium to create a work that exhibited solid design, great creativity, and strong craftsmanship. Students presented their pieces to the class for critique, explained the process, the media, and their feelings about their…

  18. Toluene 2-Monooxygenase-Dependent Growth of Burkholderia cepacia G4/PR1 on Diethyl Ether

    PubMed Central

    Hur, H.; Newman, L. M.; Wackett, L. P.; Sadowsky, M. J.

    1997-01-01

    Aerobic bacterial growth on aromatic hydrocarbons typically requires oxygenase enzymes, which are known to fortuitously oxidize nongrowth substrates. In this study, we found that oxidation of diethyl ether by toluene 2-monooxygenase supported more rapid growth of Burkholderia cepacia G4/PR1 than did the aromatic substrates n-propylbenzene and o-xylene. The wild-type Burkholderia cepacia G4 failed to grow on diethyl ether. Purified toluene 2-monooxygenase protein components oxidized diethyl ether stoichiometrically to ethanol and acetaldehyde. Butyl methyl ether, diethyl sulfide, and 2-chloroethyl ethyl ether were oxidized by B. cepacia G4/PR1. PMID:16535583

  19. Inhalation anaesthesia: from diethyl ether to xenon.

    PubMed

    Bovill, J G

    2008-01-01

    Modern anaesthesia is said to have began with the successful demonstration of ether anaesthesia by William Morton in October 1846, even though anaesthesia with nitrous oxide had been used in dentistry 2 years before. Anaesthesia with ether, nitrous oxide and chloroform (introduced in 1847) rapidly became commonplace for surgery. Of these, only nitrous oxide remains in use today. All modern volatile anaesthetics, with the exception of halothane (a fluorinated alkane), are halogenated methyl ethyl ethers. Methyl ethyl ethers are more potent, stable and better anaesthetics than diethyl ethers. They all cause myocardial depression, most markedly halothane, while isoflurane and sevoflurane cause minimal cardiovascular depression. The halogenated ethers also depress the normal respiratory response to carbon dioxide and to hypoxia. Other adverse effects include hepatic and renal damage. Hepatitis occurs most frequently with halothane, although rare cases have been reported with the other agents. Liver damage is not caused by the anaesthetics themselves, but by reactive metabolites. Type I hepatitis occurs fairly commonly and takes the form of a minor disturbance of liver enzymes, which usually resolves without treatment. Type II, thought to be immune-mediated, is rare, unpredictable and results in a severe fulminant hepatitis with a high mortality. Renal damage is rare, and was most often associated with methoxyflurane because of excessive plasma fluoride concentrations resulting from its metabolism. Methoxyflurane was withdrawn from the market because of the high incidence of nephrotoxicity. Among the contemporary anaesthetics, the highest fluoride concentrations have been reported with sevoflurane, but there are no reports of renal dysfunction associated with its use. Recently there has been a renewed interest in xenon, one of the noble gases. Xenon has many of the properties of an ideal anaesthetic. The major factor limiting its more widespread is the high cost, about

  20. Prenyl Ethers: Novel Fungal Volatiles Formed by Penicillium digitatum.

    PubMed

    Amrein, Thomas M; Frey, Peter; Meier, Roberto; Baumann, Heidi; Tanner, Miriam; Gassenmeier, Klaus F

    2014-10-01

    Prenyl ethyl ether (PEE) was previously described as the cause for a solvent-like off-note in ground hazelnuts, but its origin remained unclear. Investigations were carried out by analytical groups of Coop and Givaudan over four years to elucidate this phenomenon. From mouldy citrus fruits a strain of Penicillium digitatum was isolated and found to form PEE. Formation on citrus and other fruits was prominent and contributed to the particular smell of decayed fruits. Several strains of P. digitatum formed PEE, while other fungal species did not. In contrast to citrus fruit, prenyl methyl ether (PME) was formed as dominant prenyl ether on hazelnuts while only small amounts of PEE were found. PME has not been previously described as volatile metabolite of fungi or as a food-taint. Spiking experiments with deuterated ethanol showed that the ethyl group is likely incorporated into PEE via the aldehyde form. On hazelnuts strongly decayed by P. digitatum yet another prenyl ether was tentatively identified: Prenyl isopropyl ether. Prenyl ethers present a novel group of volatile metabolites of P. digitatum. They are likely typical for this species and have not been described before. Prenyl ethers seem to play a significant role in the smell of food decayed by P. digitatum and should be considered in cases of off-notes and taints. PMID:25437159

  1. Antioxidant activity of alkyl hydroxytyrosyl ethers in unsaturated lipids.

    PubMed

    Cert, Rosa; Madrona, Andrés; Espartero, José Luis; Pérez-Camino, M Carmen

    2015-06-01

    The antioxidant activity of ethyl and octyl hydroxytyrosyl ethers toward lipids was determined using the Rancimat and open cup methods at high temperatures and 50 °C, respectively. The effect of the unsaturation of the matrix was evaluated using sunflower, soya, and fish refined oils. The antioxidant activities of alkyl hydroxytyrosyl ethers (HTy ethers), hydroxytyrosyl esters, and free hydroxytyrosol are similar, and are much higher than that of α-tocopherol at the same millimolar concentration. The relationship between the induction period and the concentration of the HTy ethers is a sigmoidal curve; an accurate concentration of HTy ethers is necessary to achieve maximum activity, as it increases with the level of matrix unsaturation. The presence of tocopherols in commercial oils affects the antioxidant effect of HTy ethers. Thus, the addition of a low concentration of HTy ethers results in a positive effect, whereas the effect of the addition of high amounts of ethers is slightly less than that of the phenol alone. The addition of HTy ethers to commercial refined oils increases the stability of the oils and preserves tocopherols and polyunsaturated fatty acids from oxidation, enabling the oils to maintain their nutritional properties for longer periods of time. PMID:26018773

  2. AVOIDING HYDROLYSIS OF FUEL ETHER OXYGENATES DURING STATIC HEADSPACE ANALYSIS

    EPA Science Inventory

    A headspace autosampler, gas chromatograph and ion trap mass spectrometer (headspace GC/MS) were used for trace analysis of fuel oxygenates and related compounds and aromatics in water. A method has been developed for determination of methyl tert-butyl ether (MTBE), ethyl tert-b...

  3. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... borosilicate flask, and for each gram of sample add 3 milliliters of solvent previously heated to 150 °F. Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also maintaining gentle mechanical agitation. Filter the contents of the flask rapidly through No. 42...

  4. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... borosilicate flask, and for each gram of sample add 3 milliliters of solvent previously heated to 150 °F. Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also maintaining gentle mechanical agitation. Filter the contents of the flask rapidly through No. 42...

  5. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... borosilicate flask, and for each gram of sample add 3 milliliters of solvent previously heated to 150 °F. Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also maintaining gentle mechanical agitation. Filter the contents of the flask rapidly through No. 42...

  6. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... least 8 feet above the tank top or the highest level the lading may rise, whichever is greater. All openings shall be in the top of the tank. (2) Pressure vessel type tanks shall be designed for the maximum... the design pressure be less than 50 pounds per square inch gauge. All openings shall be in the top...

  7. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... openings shall be in the top of the tank. (2) Pressure vessel type tanks shall be designed for the maximum... inch gauge for gravity tanks. For pressure vessels, the relief valve setting shall not exceed the... vessel tanks provided the cargo system is designed for the expected pressure and the discharge...

  8. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... openings shall be in the top of the tank. (2) Pressure vessel type tanks shall be designed for the maximum... inch gauge for gravity tanks. For pressure vessels, the relief valve setting shall not exceed the... vessel tanks provided the cargo system is designed for the expected pressure and the discharge...

  9. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... openings shall be in the top of the tank. (2) Pressure vessel type tanks shall be designed for the maximum... inch gauge for gravity tanks. For pressure vessels, the relief valve setting shall not exceed the... vessel tanks provided the cargo system is designed for the expected pressure and the discharge...

  10. HPLC and TLC characterisation of ecdysteroid alkyl ethers.

    PubMed

    Lapenna, Silvia; Dinan, Laurence

    2009-10-01

    Semi-synthetic ecdysteroid alkyl ethers have increased potential over natural ecdysteroids as actuators of ligand-inducible gene-expression systems based on the ecdysteroid receptor for in vivo applications. However, a scalable synthesis of these compounds has yet to be developed. We report a set of reversed-phase (RP; C(18) and C(6)) and normal-phase (NP; diol) HPLC systems which can be used to analyse and separate ecdysteroid ethers with single or multiple O-methyl substitutions at the 2alpha-, 3beta-, 14alpha-, 22- and 25-positions. The elution order of methyl ether analogues of the prototypical ecdysteroid 20-hydroxyecdysone (20E) was 3-methyl<2-methyl<14-methyl<25-methyl<22-methyl with both C(18)- and C(6)-RP-HPLC, when eluted with methanol/water mixtures. Further, the elution order of 20E 22-O-alkyl ethers was methyl<ethylethers can also be adequately resolved by NP-HPLC and silica HPTLC. On the latter, detection of ecdysteroid O-alkyl ethers with the p-anisaldehyde/sulphuric acid reagent distinguishes 22-O-alkyl ethers from non-22-O-alkyl ether analogues by the colour of the resulting spot. PMID:19648067

  11. 21 CFR 172.872 - Methyl ethyl cellulose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... a cellulose ether having the general formula [C6H(10 -x-y)O5(CH3)x(C2H5)y]n, where x is the number of methyl groups and y is the number of ethyl groups. The average value of x is 0.3 and the average... the dry sample. (2) The viscosity of an aqueous solution, 2.5 grams of the material in 100...

  12. 21 CFR 172.872 - Methyl ethyl cellulose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... a cellulose ether having the general formula [C6H(10 -x-y)O5(CH3)x(C2H5)y]n, where x is the number of methyl groups and y is the number of ethyl groups. The average value of x is 0.3 and the average... the dry sample. (2) The viscosity of an aqueous solution, 2.5 grams of the material in 100...

  13. KOAc-promoted alkynylation of α-C-H bonds of ethers with alkynyl bromides under transition-metal-free conditions.

    PubMed

    Zhang, Jiajun; Li, Pinhua; Wang, Lei

    2014-05-14

    A novel KOAc-promoted α-position C-H activation and alkynylation of ethers with alkynyl bromides to 2-alkynyl ethers has been developed under transition-metal-free and simple reaction conditions. In addition, this methodology can also be extended to the vinylation of ethers with vinyl bromides in excellent regio- and stereo-selectivity. A wide range of direct C(sp)-C(sp(3)) and C(sp(2))-C(sp(3)) bonds has been formed through this protocol, which offers a new and alternative route. PMID:24691678

  14. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the Office of... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No....

  15. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the Office of Food... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No....

  16. Poly(arylene ether)s containing pendent ethynyl groups

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)

    1996-01-01

    Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350.degree. C. to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.

  17. Metal-catalyzed activation of ethers via C-O bond cleavage: a new strategy for molecular diversity.

    PubMed

    Cornella, Josep; Zarate, Cayetana; Martin, Ruben

    2014-12-01

    In 1979, the seminal work of Wenkert set the standards for the utilization of aryl and vinyl ethers as coupling partners via C-O bond-cleavage. Although the topic remained dormant for almost three decades, the last few years have witnessed a renaissance in this area of expertise, experiencing an exponential growth and becoming a significant discipline within the cross-coupling arena. The means to utilize readily accessible aryl or vinyl ethers as counterparts does not only represent a practical, powerful and straightforward alternative to organic halides, but also constitutes an excellent opportunity to improve our chemical knowledge about a relatively unexplored area of expertise. This review summarizes the most significant developments in the area of C-O bond-cleavage when employing aryl or vinyl ethers, providing a detailed overview of the current state of the art and including future aspects, when applicable. PMID:25157613

  18. A novel biobased plasticizer of epoxidized cardanol glycidylether: Synthesis and application in soft poly(vinyl chloride) films

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel plasticizer derived from cardanol, epoxied cardanol glycidyl ether (ECGE), was synthesized and characterized by 1H-NMR and 13C-NMR. Effects of the ECGE combined with dioctyl phthalate (DOP), a commercial plasticizer, in soft poly(vinyl chloride) (PVC) films were studied. Dynamic mechanical a...

  19. Rhodium(III)-catalyzed C-H activation/annulation with vinyl esters as an acetylene equivalent.

    PubMed

    Webb, Nicola J; Marsden, Stephen P; Raw, Steven A

    2014-09-19

    The behavior of electron-rich alkenes in rhodium-catalyzed C-H activation/annulation reactions is investigated. Vinyl acetate emerges as a convenient acetylene equivalent, facilitating the synthesis of sixteen 3,4-unsubstituted isoquinolones, as well as select heteroaryl-fused pyridones. The complementary regiochemical preferences of enol ethers versus enol esters/enamides is discussed. PMID:25165993

  20. Oxidative acetoxylation of the silyl ethers of ketone enols

    SciTech Connect

    Brunovlenskaya, I.I.; Kusainova, K.M.; Kashin, A.K.

    1988-07-20

    The authors studied the reaction of (dicarboxyiodo)benzenes with the trimethylsilyl ethers of ketone enols having various structures. They also undertook a comparative investigation of the oxidation of these compounds with lead tetraacetate. The reaction of (diacetoxyiodo)benzene with the trimethylsilyl ethers of ketone enols takes place with retention of the (CH/sub 3/)/sub 3/Si group in two directions, i.e., substitution of the vinylic hydrogen or diacetoxylation of the double bond. The reaction can be used for the regioselective synthesis of /alpha/-acetoxy ketones, since the trimethylsilyl group is readily eliminated from the obtained products by the action of fluoride ion or boron trifluoride etherate with the formation of the corresponding substituted ketones.

  1. Studies Update Vinyl Chloride Hazards.

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1980-01-01

    Extensive study affirms that vinyl chloride is a potent animal carcinogen. Epidemiological studies show elevated rates of human cancers in association with extended contact with the compound. (Author/RE)

  2. Copper-assisted nickel catalyzed ligand-free C(sp2)-O cross-coupling of vinyl halides and phenols.

    PubMed

    Kundu, Debasish; Maity, Pintu; Ranu, Brindaban C

    2014-02-21

    A convenient and efficient protocol has been achieved for the cross-coupling of phenols and vinyl halides by a unique Ni/Cu catalytic system for the first time, where the reaction is catalyzed by Ni and Cu is involved in the transmetalation process. This procedure provides an easy access to a library of aryl-vinyl and aryl-styrenyl ethers. PMID:24502267

  3. Chlorimuron-ethyl

    Integrated Risk Information System (IRIS)

    Chlorimuron - ethyl ; CASRN 90982 - 32 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinog

  4. Methyl ethyl ketone (MEK)

    Integrated Risk Information System (IRIS)

    Methyl ethyl ketone ( MEK ) ( CASRN 78 - 93 - 3 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonc

  5. Ethyl alcohol production

    SciTech Connect

    Hofman, V.; Hauck, D.

    1980-11-01

    Recent price increases and temporary shortages of petroleum products have caused farmers to search for alternate sources of fuel. The production of ethyl alcohol from grain is described and the processes involved include saccharification, fermentation and distillation. The resulting stillage has potential as a livestock feed.

  6. Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis

    SciTech Connect

    T.A. Semelsberger

    2004-10-01

    The thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the process of dimethyl ether (DME) steam reforming were investigated as a function of steam-to-carbon ratio (0-4), temperature (100 C-600 C), pressure (1-5 atm), and product species: acetylene, ethanol, methanol, ethylene, methyl-ethyl ether, formaldehyde, formic acid, acetone, n-propanol, ethane and isopropyl alcohol. Results of the thermodynamic processing of dimethyl ether with steam indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure was observed to shift the equilibrium toward the reactants; increasing the pressure from 1 atm to 5 atm decreased the conversion of dimethyl ether from 99.5% to 76.2%. The order of thermodynamically stable products in decreasing mole fraction was methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol--formaldehyde, formic acid, and acetylene were not observed. The optimal processing conditions for dimethyl ether steam reforming occurred at a steam-to-carbon ratio of 1.5, a pressure of 1 atm, and a temperature of 200 C. Modeling the thermodynamics of dimethyl ether hydrolysis (with methanol as the only product considered), the equilibrium conversion of dimethyl ether is limited. The equilibrium conversion was observed to increase with temperature and steam-to-carbon ratio, resulting in a maximum dimethyl ether conversion of approximately 68% at a steam-to-carbon ratio of 4.5 and a processing temperature of 600 C. Thermodynamically, dimethyl ether processed with steam can produce hydrogen-rich fuel-cell feeds--with hydrogen concentrations exceeding 70%. This substantiates dimethyl ether as a viable source of hydrogen for PEM fuel cells.

  7. Crown ethers in graphene

    SciTech Connect

    Guo, Junjie; Lee, Jaekwang; Contescu, Cristian I.; Gallego, Nidia C.; Pantelides, Sokrates T.; Pennycook, Stephen J.; Moyer, Bruce A.; Chisholm, Matthew F.

    2014-11-13

    Crown ethers, introduced by Pedersen1, are at their most basic level neutral rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted special attention for their ability to selectively incorporate various atoms2 or molecules within the cavity formed by the ring3-6. This property has led to the use of crown ethers and their compounds in a wide range of chemical and biological applications7,8. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many uses that demand higher binding affinity and selectivity9,10. In this Letter, we report atomic-resolution images of the same basic structures of the original crown ethers embedded in graphene. This arrangement constrains the crown ethers to be rigid and planar and thus uniquely suited for the many applications that crown ethers are known for. First-principles calculations show that the close similarity of the structures seen in graphene with those of crown ether molecules also extends to their selectivity towards specific metal cations depending on the ring size. Atoms (or molecules) incorporated within the crown ethers in graphene offer a simple environment that can be easily and systematically probed and modeled. Thus, we expect that this discovery will introduce a new wave of investigations and applications of chemically functionalized graphene.

  8. Crown ethers in graphene

    DOE PAGESBeta

    Guo, Junjie; Lee, Jaekwang; Contescu, Cristian I.; Gallego, Nidia C.; Pantelides, Sokrates T.; Pennycook, Stephen J.; Moyer, Bruce A.; Chisholm, Matthew F.

    2014-11-13

    Crown ethers, introduced by Pedersen1, are at their most basic level neutral rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted special attention for their ability to selectively incorporate various atoms2 or molecules within the cavity formed by the ring3-6. This property has led to the use of crown ethers and their compounds in a wide range of chemical and biological applications7,8. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many uses that demand higher binding affinity and selectivity9,10. In this Letter, we report atomic-resolution images of the same basicmore » structures of the original crown ethers embedded in graphene. This arrangement constrains the crown ethers to be rigid and planar and thus uniquely suited for the many applications that crown ethers are known for. First-principles calculations show that the close similarity of the structures seen in graphene with those of crown ether molecules also extends to their selectivity towards specific metal cations depending on the ring size. Atoms (or molecules) incorporated within the crown ethers in graphene offer a simple environment that can be easily and systematically probed and modeled. Thus, we expect that this discovery will introduce a new wave of investigations and applications of chemically functionalized graphene.« less

  9. Crown ethers in graphene

    NASA Astrophysics Data System (ADS)

    Guo, Junjie; Lee, Jaekwang; Contescu, Cristian I.; Gallego, Nidia C.; Pantelides, Sokrates T.; Pennycook, Stephen J.; Moyer, Bruce A.; Chisholm, Matthew F.

    2014-11-01

    Crown ethers are at their most basic level rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted attention for their ability to selectively incorporate various atoms or molecules within the cavity formed by the ring. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many uses that demand higher binding affinity and selectivity. Here we present atomic-resolution images of the same basic structures of the original crown ethers embedded in graphene. This arrangement constrains the crown ethers to be rigid and planar. First-principles calculations show that the close similarity of the structures should also extend to their selectivity towards specific metal cations. Crown ethers in graphene offer a simple environment that can be systematically tested and modelled. Thus, we expect that our finding will introduce a new wave of investigations and applications of chemically functionalized graphene.

  10. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Vinyl chloride (vinyl chloride monomer). 151.50-34 Section 151.50-34 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-34 Vinyl chloride (vinyl chloride monomer). (a)...

  11. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Mannheim, DE; Meshulam-Simon, Galit [Los Angeles, CA; McCarty, Perry L [Stanford, CA

    2014-02-11

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  12. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M.; Muller, Jochen A.; Rosner, Bettina M.; Von Abendroth, Gregory; Meshulam-Simon, Galit; McCarty, Perry L

    2011-11-22

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  13. INTRAVENOUS ETHER ANESTHESIA

    PubMed Central

    Eger, Edmond I.; Johnson, Edward A.

    1963-01-01

    From a study of intravenous ether anesthesia, it was concluded that ether diluted to a 5 per cent solution in 5 per cent dextrose and water may be used to induce and maintain a smooth and easily controlled anesthetic state similar to that obtained with inhalation ether but without the dependence of the latter technique on ventilation. Cough and laryngospasm were absent. Adequate spontaneous respiration can be maintained with this technique. The technique is particularly useful in endoscopy during which the airway is often not available for anesthetic administration. PMID:14051486

  14. Genotoxicity of glycol ethers.

    PubMed Central

    McGregor, D B

    1984-01-01

    The genetic toxicology of glycol ethers is reviewed. Ethylene glycol monomethyl ether (EGME) and diglyme have been more extensively studied than other members of this series. Most results indicate a lack of genotoxic potential, but certain tests have yielded positive responses with certain compounds. Ethylene glycol monoethyl ether (EGEE) induced sister chromatid exchanges and chromosomal aberrations in cultured cells. Both EGME and diglyme induced mouse sperm head morphological changes, male rat weak dominant lethal mutations and marked, but reversible, loss of male rat fertility. PMID:6541999

  15. Catalytic oxidation of dimethyl ether

    DOEpatents

    Zelenay, Piotr; Wu, Gang; Johnston, Christina M.; Li, Qing

    2016-05-10

    A composition for oxidizing dimethyl ether includes an alloy supported on carbon, the alloy being of platinum, ruthenium, and palladium. A process for oxidizing dimethyl ether involves exposing dimethyl ether to a carbon-supported alloy of platinum, ruthenium, and palladium under conditions sufficient to electrochemically oxidize the dimethyl ether.

  16. Two Unrelated 8-Vinyl Reductases Ensure Production of Mature Chlorophylls in Acaryochloris marina

    PubMed Central

    Chen, Guangyu E.; Hitchcock, Andrew; Jackson, Philip J.; Chaudhuri, Roy R.; Dickman, Mark J.; Hunter, C. Neil

    2016-01-01

    ABSTRACT The major photopigment of the cyanobacterium Acaryochloris marina is chlorophyll d, while its direct biosynthetic precursor, chlorophyll a, is also present in the cell. These pigments, along with the majority of chlorophylls utilized by oxygenic phototrophs, carry an ethyl group at the C-8 position of the molecule, having undergone reduction of a vinyl group during biosynthesis. Two unrelated classes of 8-vinyl reductase involved in the biosynthesis of chlorophylls are known to exist, BciA and BciB. The genome of Acaryochloris marina contains open reading frames (ORFs) encoding proteins displaying high sequence similarity to BciA or BciB, although they are annotated as genes involved in transcriptional control (nmrA) and methanogenesis (frhB), respectively. These genes were introduced into an 8-vinyl chlorophyll a-producing ΔbciB strain of Synechocystis sp. strain PCC 6803, and both were shown to restore synthesis of the pigment with an ethyl group at C-8, demonstrating their activities as 8-vinyl reductases. We propose that nmrA and frhB be reassigned as bciA and bciB, respectively; transcript and proteomic analysis of Acaryochloris marina reveal that both bciA and bciB are expressed and their encoded proteins are present in the cell, possibly in order to ensure that all synthesized chlorophyll pigment carries an ethyl group at C-8. Potential reasons for the presence of two 8-vinyl reductases in this strain, which is unique for cyanobacteria, are discussed. IMPORTANCE The cyanobacterium Acaryochloris marina is the best-studied phototrophic organism that uses chlorophyll d for photosynthesis. Unique among cyanobacteria sequenced to date, its genome contains ORFs encoding two unrelated enzymes that catalyze the reduction of the C-8 vinyl group of a precursor molecule to an ethyl group. Carrying a reduced C-8 group may be of particular importance to organisms containing chlorophyll d. Plant genomes also contain orthologs of both of these genes; thus, the

  17. CHEMILUMINESCENT MONITOR FOR VINYL CHLORIDE

    EPA Science Inventory

    A monitor for vinyl chloride monomer (VCM) in ambient air was constructed using commercially available components of a gas chromatograph (GC) coupled with a chemiluminescence ozone analyzer slightly modified to make it suitable for use as a GC detector. The specificity for VCM is...

  18. Discrimination against diacylglycerol ethers in lipase-catalysed ethanolysis of shark liver oil.

    PubMed

    Fernández, Óscar; Vázquez, Luis; Reglero, Guillermo; Torres, Carlos F

    2013-01-15

    Lipase-catalysed ethanolysis of squalene-free shark liver oil was investigated. The mentioned shark liver oil was comprised mainly of diacylglycerol ether and triacylglycerols. In order to test discrimination against diacylglycerol ether, up to 10 different lipases were compared. The ratio of oil to ethanol and lipase stability were also evaluated. Surprisingly, lipase from Pseudomonas stutzeri was the fastest biocatalyst among all assayed, although poor discrimination against diacylglycerol ether was observed. The best results in terms of selectivity and stability were obtained with immobilised lipase from Candida antarctica (Novozym 435). Ethanolysis reaction after 24h in the presence of Novozym 435 produced total disappearance of triacylglycerol and a final reaction mixture comprised mainly of diacylglycerol ethers (10.6%), monoacylglycerol ethers (32.9%) and fatty acid ethyl esters (46.0%). In addition, when an excess of ethanol was used, diacylglycerol ethers completely disappeared after 15 h, giving a final product mainly composed of monoacylglycerol ethers (36.6%) and fatty acid ethyl esters (46.4%). PMID:23122085

  19. Comparison of surface modification of poly(ether urethanes) on physical properties and blood compatibility

    SciTech Connect

    Wrobleski, D.A.; Cash, D.L.; Hermes, R.E.

    1988-01-01

    Because of their good elastomeric properties including the ability to undergo repeated flexing without failure, polyurethanes are used in a number of biomedical applications including flexing diaphragms or coatings on surfaces in artificial hearts and heart assist devices. In particular, the poly(ether urethanes), are preferred for use in biomedical applications because of their greater hydrolytic stability as compared to poly(ester urethanes). However, poly(ether urethanes), as other polymeric materials in contact with blood, cause formation of thrombus and bacterial infections. These problems might be overcome by incorporation of antithrombogenic substances and/or antibacterial agents in the surface of the polymer. We have explored both of these methods by examining the infusion of polyvinylpyrrolidone (PVP) and poly(ethylene glycol) (PEG) into commercially available poly(ether urethanes) and the graft polymerization of N-vinyl pyrrolidone onto poly(ether urethanes). Preliminary results are presented here. 7 refs., 1 fig.

  20. Changes in Chemical Permeation of Disposable Latex, Nitrile and Vinyl Gloves Exposed to Simulated Movement

    PubMed Central

    Phalen, Robert N.; Le, Thi; Wong, Weng Kee

    2014-01-01

    Glove movement can affect chemical permeation of organic compounds through polymer glove products. However, conflicting reports make it difficult to compare the effects of movement on chemical permeation through commonly available glove types. This study was aimed to evaluate the effect of movement on chemical permeation of an organic solvent through disposable latex, nitrile, and vinyl gloves. Simulated whole-glove permeation testing was conducted using ethyl alcohol and a previously designed permeation test system. With exposure to movement, a significant decrease (p ≤ 0.001) in breakthrough time was observed for the latex (-23%) and nitrile gloves (-31%). With exposure to movement, only the nitrile glove exhibited a significant increase (p ≤ 0.001) in steady-state permeation rate (+47%) and cumulative permeation at 30 min (+111%). Even though the nitrile glove provided optimum chemical resistance against ethyl alcohol, it was most affected by movement. With exposure to movement, the latex glove was an equivalent option for overall worker protection, because it was less affected by movement and the permeation rate was lower than that of the nitrile glove. In contrast, the vinyl glove was the least affected by movement, but did not provide adequate chemical resistance to ethyl alcohol in comparison with the nitrile and latex gloves. In conclusion, glove selection should take movement and polymer type into account. Some glove polymer types are less affected by movement, most notably the latex glove in this test. With nitrile gloves, at least a factor of three should be used when attempting to assign a protection factor when repetitive hand motions are anticipated. Ultimately, the latex gloves outperformed nitrile and vinyl in these tests, which evaluated the effect of movement on chemical permeation. Future research should aim to resolve some of the observed discrepancies in test results with latex and vinyl gloves. PMID:24689368

  1. Changes in chemical permeation of disposable latex, nitrile, and vinyl gloves exposed to simulated movement.

    PubMed

    Phalen, Robert N; Le, Thi; Wong, Weng Kee

    2014-01-01

    Glove movement can affect chemical permeation of organic compounds through polymer glove products. However, conflicting reports make it difficult to compare the effects of movement on chemical permeation through commonly available glove types. The aim of this study was to evaluate the effect of movement on chemical permeation of an organic solvent through disposable latex, nitrile, and vinyl gloves. Simulated whole-glove permeation testing was conducted using ethyl alcohol and a previously designed permeation test system. With exposure to movement, a significant decrease (p ≤ 0.001) in breakthrough time (BT) was observed for the latex (-23%) and nitrile gloves (-31%). With exposure to movement, only the nitrile glove exhibited a significant increase (p ≤ 0.001) in steady-state permeation rate (+47%) and cumulative permeation at 30 min (+111%). Even though the nitrile glove provided optimum chemical resistance against ethyl alcohol, it was most affected by movement. With exposure to movement, the latex glove was an equivalent option for overall worker protection, because it was less affected by movement and the permeation rate was lower than that of the nitrile glove. In contrast, the vinyl glove was the least affected by movement, but did not provide adequate chemical resistance to ethyl alcohol in comparison with the nitrile and latex gloves. Glove selection should take movement and polymer type into account. Some glove polymer types are less affected by movement, most notably the latex glove in this test. With nitrile gloves, at least a factor of three should be used when attempting to assign a protection factor when repetitive hand motions are anticipated. Ultimately, the latex gloves outperformed nitrile and vinyl in these tests, which evaluated the effect of movement on chemical permeation. Future research should aim to resolve some of the observed discrepancies in test results with latex and vinyl gloves. PMID:24689368

  2. Determination of residual vinyl chloride in polyvinyl chloride, vinyl chloride copolymers, and articles from polyvinyl chloride by the method of equilibrium vapor analysis

    SciTech Connect

    Kalmykova, T.A.; Konstantinova, E.I.; Lazaris, A. Ya.

    1985-11-01

    In connection with the fact that vinyl chloride (VC) has carcinogenic properties, norms for its content both in the work place and also in polyvinyl chloride (PVC) and articles made from it have been sharply reduced. The method of equilibrium vapor analysis (EVA) has been used to determine vinyl chloride; this is carried out with the aid of devices for automatic metering. In the present work, the authors have investigated the possibility of applying the EVA method to PVC resins, VC copolymers, and articles made of PVC with the objective of developing universal methods of analyzing such objects. A two-stage separation is used in which the sample is preliminarily separated in a fore-column. The separation was worked out on the model mixture of methyl chloride-VC-ethyl chloride. The limit of VC detection is shown to be 5 x 10/sup -6/ to 5 x 10/sup -7/% by wt.

  3. Laboratory Method for Analysis of Small Concentrations of Methyl tert-Butyl Ether and Other Ether Gasoline Oxygenates in Water

    USGS Publications Warehouse

    Rose, Donna L.; Connor, Brooke F.; Abney, Sonja R.; Raese, Jon W.

    1998-01-01

    This Fact Sheet presents data for analysis of nanogram-per-liter concentrations of methyl tert-butyl ether (MTBE) and three other ether gasoline oxygenates, including methyl tert-pentyl ether (TAME), diisopropyl ether (DIPE), and ethyl tert-butyl ether (ETBE), by purge- and-trap capillary-column gas chromatography. Long-term method detection levels (LT-MDLs) for MTBE, TAME, DIPE, and ETBE ranged from 15 to 83 nanograms per liter (0.015 to 0.083 microgram per liter). Nanogram-per-liter-concentration detections are reported if all of the identification criteria are met, whereas previous methods censored detections at a pre-determined method reporting level. The reporting level for this method is defined as two times the LT-MDL, does not censor detections at less than this concentration, and is referred to as the nondetection value (NDV). Bias and variability data from multiple analyses, analysts, and instruments over a 60-day period show the oxygenate recoveries ranging from 100 to 109 percent, with 6 to 8 percent relative standard deviation. MTBE, TAME, DIPE, and ETBE were not detected in the analysis of 225 laboratory reagent blanks from January to December 1997. A preservation study in ground water and surface water indicates that all the oxygenates are stable at pH 2 for up to 216 days, with recoveries ranging from 94 to 115 percent on day 216, and relative standard deviations ranging from 5 to 9 percent for the duration of the study.

  4. In vivo biocompatibility studies of poly( n-vinyl 2-pyrrolidone/itaconic acid) hydrogels synthesized by γ-rays

    NASA Astrophysics Data System (ADS)

    Özdemir, S.; Özdemir, E.; Tunca, R.; Hazıroǧlu, R.; Şen, M.; Kantoǧlu, Ö.; Güven, O.

    2003-08-01

    In this study, poly( n-vinyl 2-pyrrolidone/itaconic acid) hydrogels have been synthesized by γ-rays in different compositions and their biocompatibility have been investigated as in vivo and some biochemical parameters of mice serum and histology of their tissues have been examined. By these purposes, poly( n-vinyl 2-pyrrolidone/itaconic acid) (P(VP/IA)) hydrogels were implanted to hypersensitive mice (BALB/c). One and a half months after implantation, hydrogel implanted animals were sacrificed by ether anesthesia and the area hydrogel contacted with tissue was investigated by light microscope for histopathological identification of the tissue. Then the total immunoglobulin E (IgE) level was determined by ELISA. Differential white cell count was also made to better understanding of reaction between hydrogel and tissue. These poly( n-vinyl 2-pyrrolidone/itaconic acid) hydrogels can be directly used as biomedical materials.

  5. Aqueous DMSO Mediated Conversion of (2-(Arylsulfonyl)vinyl)iodonium Salts to Aldehydes and Vinyl Chlorides.

    PubMed

    Zawia, Eman; Moran, Wesley J

    2016-01-01

    Vinyl(aryl)iodonium salts are useful compounds in organic synthesis but they are under-utilized and their chemistry is under-developed. Herein is described the solvolysis of some vinyl(phenyl)iodonium salts, bearing an arylsulfonyl group, in aqueous DMSO leading to aldehyde formation. This unusual process is selective and operates under ambient conditions. Furthermore, the addition of aqueous HCl and DMSO to these vinyl(aryl)iodonium salts allows their facile conversion to vinyl chlorides. PMID:27537866

  6. Ruthenium Vinyl Carbene Intermediates in Enyne Metathesis

    PubMed Central

    Diver, Steven T.

    2009-01-01

    This review provides an overview of ruthenium vinyl carbene reactivity as it relates to enyne metathesis. Methods for the synthesis of metathesis-active and metathesis-inactive complexes are also summarized. Some of the early hypotheses about vinyl carbene intermediates in enyne metatheses were tested in the arena of synthetic chemistry and subsequently led to mechanistic studies. In these two areas, studies from the author's labs are described. There are still many unresolved questions in enyne metathesis that trace back to vinyl carbene reactivity. Hopefully this review will stimulate further investigation into vinyl carbene reactivity which should further refine our understanding of catalytic enyne metathesis. PMID:19590747

  7. Triethylene glycol monoethyl ether

    Integrated Risk Information System (IRIS)

    Triethylene glycol monoethyl ether ; CASRN 112 - 50 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  8. Triethylene glycol monobutyl ether

    Integrated Risk Information System (IRIS)

    Triethylene glycol monobutyl ether ; CASRN 143 - 22 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  9. Propylene glycol monoethyl ether

    Integrated Risk Information System (IRIS)

    Propylene glycol monoethyl ether ; CASRN 52125 - 53 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  10. p-Bromodiphenyl ether

    Integrated Risk Information System (IRIS)

    p - Bromodiphenyl ether ; CASRN 101 - 55 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin