- Radiation-induced reactions of benzoyl chloride and acrylates in solution. A pulse radiolysis study
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Using electron pulse radiolysis with optical detection, the radiation- induced reactions of benzoyl chloride and acrylates were studied in tetrahydrofuran and acetonitrile solution at room temperature. In both solvents electron transfer leads to the formation of transient radical anions of acrylates (k ? 2-3 x 1010 dm3 mol-1 s-1) and of benzoyl chloride (k ? 3 x 1010 dm3 mol-1 s-1). The latter dissociates into chloride ion and the benzoyl radical (k = 3 x 106 s-1), whereas the acrylate anion transforms by protonation into a ketyl-type radical. In mixed solutions a fast electron transfer from acrylate anions to benzoyl chloride is found (k ? 1 x 1010 dm3 mol-1 s-1). The benzoyl chloride anion reacts with the monomer (k = 2.8 x 109 dm3 mol-1 s-1) with simultaneous release of Cl- , forming species which may initiate polymerization. In the presence of oxygen the formation of benzoylperoxy radicals (k = 1.6 x 109 dm3 mol-1 s-1), showing a strong absorption band in the near-UV (λ(max) = 400 nm), is observed.
- Knolle, Wolfgang,Mueller, Uwe,Mehnert, Reiner
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- Free radical and nitroxide mediated polymerization of hydroxy-functional acrylates prepared via lipase-catalyzed transacylation reactions
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3-Hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-methyl-3-hydroxypropyl acrylate, 2-hydroxypropyl acrylate, neopentyl glycol acrylate, glyceryl acrylate, and dihydroxyhexyl acrylate were prepared via transacylation reaction of methyl acrylate with diols and triols catalyzed by Candida antarctica lipase B. After removal of the enzyme by filtration and the methyl acrylate by distillation, the monomers were polymerized via free radical polymerization (FRP) with azobisisobutyronitrile as initiator and nitroxide mediated polymerization (NMP) employing Blocbuilder alkoxyamine initiator and SG-1 free nitroxide resulting in hydroxy functional poly(acrylates). The NMP kinetics are discussed in detail. In addition, the polymers obtained by FRP and NMP are compared and the results are related to the amount of bisacrylates that are present in the initial monomer mixtures resulting from the transacylation reactions
- Popescu, Dragos,Hoogenboom, Richard,Keul, Helmut,Moeller, Martin
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- Runge-Kutta analysis for optimizing the Zn-catalyzed transesterification conditions of MA and MMA with diols to maximize monoesterified products
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Terminal hydroxylated acrylates and methacrylates were prepared by catalytic transesterification of acrylates and methacrylates with diols catalyzed by a system of a tetranuclear zinc alkoxide, [Zn(tmhd)(OMe)(MeOH)]4 (1a), with 4 equiv. of 2,2′-bipyridine (L1). The reaction time to reach the equilibrium state was analyzed by kinetic studies and a curve-fitting analysis based on the Runge-Kutta method for optimizing the best reaction conditions for mono-esterification. In addition to these kinetic analyses, DFT calculations estimated a proposed mechanism of the catalytic transesterification. This journal is
- Kato, Taito,Akebi, Shin-Ya,Nagae, Haruki,Yonehara, Koji,Oku, Tomoharu,Mashima, Kazushi
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- A facile approach to bis(Isoxazoles), promising ligands of the ampa receptor
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A convenient synthetic approach to novel functionalized bis(isoxazoles), the promising bivalent ligands of the AMPA receptor, was elaborated. It was based on the heterocyclization reactions of readily available electrophilic alkenes with the tetranitromethane-triethylamine complex. The structural diversity of the synthesized compounds was demonstrated. In the electrophysi-ological experiments using the patch clamp technique on Purkinje neurons, the compound 1,4-phenylenedi(methylene)bis(5-aminoisoxazole-3-carboxylate) was shown to be highly potent positive modulator of the AMPA receptor, potentiating kainate-induced currents up to 70% at 10?11 M.
- Averina, Elena B.,Grigoriev, Vladimir V.,Grishin, Yuri K.,Karlov, Dmitry S.,Kuznetsova, Tamara S.,Palyulin, Vladimir A.,Radchenko, Eugene V.,Rybakov, Victor B.,Sadovnikov, Kirill S.,Sedenkova, Kseniya N.,Vasilenko, Dmitry A.,Zamoyski, Vladimir L.
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- Catalyzed synthesis method for 1,4-butanediol acrylate by means of solid acid
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The invention provides a catalyzed synthesis method for 1,4-butanediol acrylate by means of solid acid. The method comprises the step that under the catalyzing effect of a solid-acid catalyst, crylic acid reacts with 1,4-butanediol for two to eight hours at 110-140 DEG C for preparing the 1,4-butanediol acrylate, wherein the molar ratio of the crylic acid to the 1,4-butanediol is 2.5:1-5:1, and the mass of the solid-acid catalyst is 1-20% of that of the 1,4-butanediol. The efficiency for catalyzing the 1,4-butanediol acrylate by means of the solid acid is high, and the selectivity of the 1,4-butanediol acrylate is high, so that the catalyzed synthesis method for the 1,4-butanediol acrylate by means of the solid acid has wide application prospects.
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Paragraph 0015; 0016; 0017; 0018; 0019; 0020; 0021-0027
(2017/05/13)
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- Hydroxy functional acrylate and methacrylate monomers prepared via lipase-catalyzed transacylation reactions
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Candida antarctica lipase B (CAL-B, Novozyme 435) catalyzes the transacylation of methyl acrylate and methyl methacrylate with diols and triols in 2-methyl-2-butanol at 50 °C. Under the experimental conditions, up to 70 mol% of the acyl donor methyl acrylate was converted. Methyl methacrylate is the less efficient acyl donor (up to 60 mol%) due to the higher sterical hindrance in the enzymatic transacylation. Under the reaction conditions high yields of the mono-acylated products are obtained, which contain minor amounts of bis(meth)acrylates. In addition it was observed that Novozyme 435 catalyzes regioselectively the acylation of the primary hydroxyl groups. In comparison with the chemical catalyzed route no selectivity was observed for unsubstituted diols. For substituted diols more mono-acylated product was formed in the lipase-catalyzed reaction than in the chemical catalyzed reaction.
- Popescu, Dragos,Hoogenboom, Richard,Keul, Helmut,Moeller, Martin
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experimental part
p. 80 - 89
(2010/08/20)
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- BIOABSORBABLE ELASTOMERIC POLYMER NETWORKS, CROSS-LINKERS AND METHODS OF USE
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The invention provides elastomeric polymer networks and semi-interpenetrating networks in which a linear PEA, PEUR or PEU polymer is crosslinked by ester or alpha- amino-acid containing cross-linkers that polymerize upon exposure to active species. Bioabsorbable elastomeric internal fixation devices fabricated using such polymer networks and semi-interpenetrating networks are useful for in vivo implant and delivery of a variety of different types of molecules in a time release fashion. Alpha-amino-acid containing ester amide cross-linkers are also provided by the invention.
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Page/Page column 54
(2008/12/04)
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- Process for the conversion of aldehydes to esters
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A process for the conversion of aldehydes to esters, specifically acrolein or methacrolein to methyl acrylate or methyl methacrylate, respectively. Essentially in the absence of water, an aldehyde is contacted with an oxidizing agent to form an intermediate and then the intermediate is contacted with a diol or an alcohol to form an ester or diester. Preferably, the oxidizing agent is also a chlorinating agent. Specifically, acrolein or methacrolein is contacted with an oxidizing/chlorinating agent, such as t-butyl hypochlorite, and the chlorinated compound is contacted with an alcohol, such as methanol, to form methyl acrylate or methyl methacrylate, respectively. Generally, the order of addition is for the oxidizing agent to be added to the aldehyde, specifically for t-butyl hypochlorite to be added to acrolein or methacrolein, and for the diol or alcohol to be added to the intermediate, specifically for the methanol to be added to the reaction product of acrolein or methacrolein and t-butyl hypochlorite. The process of the present invention can be carried out in the absence or in the presence of solvent. Generally, better methyl acrylate or methyl methacrylate yields are obtained at lower reaction temperatures.
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Page/Page column 3-4
(2010/01/31)
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- Method for producing 4-hydroxybutyl (meth)acrylate
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4-Hydroxybutyl (meth)acrylate is prepared by reacting (meth)acrylic acid with 1,4-butanediol in the presence of an acidic catalyst. 1,4-Butanediol di(meth)acrylate is added at the beginning of the reaction and the ratios of the butanediol to the acid and of the ester to the acid are kept within specified ranges during the course of the reaction.
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- Novel fluorine-containing acrylic acid derivative and polymer thereof
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A novel fluorine-containing acrylic acid derivative of the invention is represented by the formula: wherein A is a residue derived from an organic compound having at least two active hydrogen atoms derived by removing at least two active hydrogen atoms, and p is an integer corresponding to the valency of the residue A, which is easily cured.
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- Stabilized acrylic acid esters of polyhydric alcohols and a process for their preparation
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Stabilized acrylic acid esters of polyhydric alcohols which contain as stabilizers polymerisation inhibitors including small amounts of compounds of the styrene type show a non-reduced polymerisation reactivity.
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