- Poly(Alkyl Glycidate Carbonate)s as Degradable Pressure-Sensitive Adhesives
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Insertion of CO2 into the polyacrylate backbone, forming poly(carbonate) analogues, provides an environmentally friendly and biocompatible alternative. The synthesis of five poly(carbonate) analogues of poly(methyl acrylate), poly(ethyl acrylate), and poly(butyl acrylate) is described. The polymers are prepared using the salen cobalt(III) complex catalyzed copolymerization of CO2 and a derivatized oxirane. All the carbonate analogues possess higher glass-transition temperatures (Tg=32 to ?5 °C) than alkyl acrylates (Tg=10 to ?50 °C), however, the carbonate analogues (Td≈230 °C) undergo thermal decomposition at lower temperatures than their acrylate counterparts (Td≈380 °C). The poly(alkyl carbonates) exhibit compositional-dependent adhesivity. The poly(carbonate) analogues degrade into glycerol, alcohol, and CO2 in a time- and pH-dependent manner with the rate of degradation accelerated at higher pH conditions, in contrast to poly(acrylate)s.
- Beharaj, Anjeza,Ekladious, Iriny,Grinstaff, Mark W.
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- Study of liquid–solid catalytic reaction of epichlorohydrin with sodium butyrate in the presence of tetrabutylammonium bromide
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The liquid–solid catalytic reaction of epichlorohydrin and sodium butyrate with tetrabutylammonium bromide as a phase transfer catalyst was studied in this paper. The shrinking core model was applied. The analysis of the reaction based on the kinetic model showed a reaction-controlled regime at temperatures varying from 90 to 100°C. The exterior diffusivity was removed between 300 and 400 rpm. The internal diffusivity was removed when the particle size was 2 × 10–4 m. Reaction rate constants were calculated at different temperatures. The correlation was obtained when the proposed kinetic model was applied to all the experimental data for predictive evaluations and the activation energy was 37.01 kJ mol–1.
- Huang, Qiang,Meng, Qingyi,Ban, Chunlan,Zhang, Rui,Gao, Yingyu
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- Synthesis and enzymatic resolution of racemic 2,3-epoxy propyl esters obtained from glycerol
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A method is described for the synthesis of (±)-2,3-epoxy propyl esters from glycerol, involving reaction of epichlorohydrin with sodium or potassium salts of carboxylic acids in the presence of TBAB as catalyst, with moderate to excellent yields. Kinetic resolution of glycidyl butyrate by lipase of Thermomyces lanuginosa has been achieved with remarkable enantiomeric excess (ee >99%) using 1,4-dioxane as a co-solvent in pure buffer solution (30 and 50 °C, pH = 7.0).
- Araujo, Yara Jaqueline Kerber,Avvari, Naga Prasad,Paiva, Derisvaldo Rosa,De Lima, Dênis Pires,Beatriz, Adilson
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supporting information
p. 1696 - 1698
(2015/03/14)
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- Stereoselective synthesis of (R)-glycidyl butyrate from racemic glycidyl butyrate or epichlorohydrin via hydrolytic kinetic resolution
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The differences of (R)-glycidyl butyrate synthesis via hydrolytic kinetic resolution of glycidyl butyrate directly or regioselective opening epichlorohydrin as key steps by using Jacobsen's hydrotic kinetic resolution are compared. In the view of separation problem, it is hard to get the pure (R)-glycidyl butyrate by kinetic resolution of glycidyl butyrate directly. Via kinetic resolution of epichlorohydrin, treatment with butyric acid in the presence of CrCl3 and then epoxidation with NaOH, the total yield of 38.5% and optical purity of 99% are obtained.
- Jiang, Chengjun,Yan, Jianbo
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scheme or table
p. 242 - 243
(2012/05/19)
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- Novel synthesis and enzymatic resolution of (±)-2,3-epoxy propyl esters
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A novel method of synthesizing glycidyl esters (±) -2,3-epoxy propyl esters has been developed involving reaction of epichlorohydrin with sodium salt of carboxylic acids in the presence of 15-crown-5 as catalyst with excellent yields. Enzymatic resolution of these glycidyl esters by lipasePS- C has been achieved with remarkable substrate selectivity.
- Nair, Ranjeet V.,Patil, Prashant N.,Salunkhe, Manikrao M.
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p. 2559 - 2566
(2007/10/03)
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- A three-step-one-pot chemo-enzymatic synthesis of epoxyalkanolacylates
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Using the ability of Novozym 435 to catalyze both the perhydrolysis and the interesterification of esters, unsaturated primary alcohols are converted with an ester and hydrogen peroxide to give esters of epoxidized alcohols directly in a convenient three-step-one-pot synthesis with yields of 66-89%.
- Klaas, M. Ruesch,Warwel
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p. 251 - 260
(2007/10/03)
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- Resolution of glycidyl esters to high enantiomeric excess
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A method of resolving glycidyl esters to high enantiomeric excess involves fractionation of hydrolytic enzymes (e.g. lipases) to prepare biocatalysts with high enantioselectivity, and using these catalysts to selectively hydrolyze one enantiomer of the glycidyl esters. Also a method for fractionation includes stirring an aqueous solution of the enzyme with a solid inert adsorbent to provide an adsorbed and non-adsorbed enzyme fraction, where the non-adsorbed fraction displays a higher enantioselectivity than the crude non-fractionated enzyme. Also a composition composed of a glycidyl ester is obtained with an enantiomeric excess of greater than or equal to 97%.
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- Method of optically resolving a racemate or a diastereomeric mixture of glycidyl compound
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A method of optically resolving a racemate, or a diastereomeric mixture, of a substituted or unsubstituted glycidyl ester or ether compound having at least one glycidylic structure represented by the formula STR1 wherein R1, R2 and R3, independently from each other, represent H or CH3, and 1 to 3 asymmetric carbon atoms in the molecule, or a racemate of a beta-dihalohydrin ester compound, which comprises contacting said racemate or diastereomeric mixture with an optically active form of a compound having the following formula (I) STR2 wherein X represents a halogen atom, to form an inclusion complex compound having the optically active compound of formula (I) as a host, and separating the resulting complex compound.
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- An Electron Spin Resonance Study of 3-Oxypropenoyl Radicals derived from Glycidols
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Glycidols with blocked OH groups (A; M = alkyl or trialkylsilyl) react with t-butoxyl radicals to show the e.s.r. spectra of the corresponding 3-oxypropenoyl radicals (D), and 24 examples of these acyl radicals are reported.The reaction is thought to proceed through the formation of the allyloxyl radicals (B), which, in part, are converted into the aldehyde (C) which is very reactive towards loss of hydrogen to give the acyl radical (D).Glycidyl pivalate (A; M = COCMe3) reacts cleanly in this way, but glycidyl acetate (E; R = Me) also undergoes intramolecular 1,5-transfer of the acyl group to show the spectrum of the enoxyl radical (F).Glycidyl propionate and butyrate do not undergo this acyl transfer, but show the spectra of the radicals and (R' = Me or Et).
- Davies, Alwyn G.,Hawari, Jalal A.-A.,Muggleton, Brenda,Tse, Man-Wing
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p. 1132 - 1137
(2007/10/02)
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