- Phosphine-Catalyzed Cascade Annulation of MBH Carbonates and Diazenes: Synthesis of Hexahydrocyclopenta[c]pyrazole Derivatives
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A phosphine-catalyzed cascade annulation of Morita-Baylis-Hillman (MBH) carbonates and diazenes was achieved, giving tetrahydropyrazole-fused heterocycles bearing two five-membered rings in moderate to excellent yields. The reaction underwent an unprecedented reaction mode of MBH carbonates, in which two molecules of MBH carbonates were fully merged into the ring system.
- Guo, Hongchao,Li, Hongxiang,Liu, Hao,Shi, Wangyu,Wang, Chang,Wang, Wei,Wu, Yongjun
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supporting information
p. 5571 - 5575
(2021/07/31)
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- Method for synthesizing low-carbon alcohol acrylate from acetylene through carbonylation
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The invention relates to a method for synthesizing low-carbon alcohol acrylate from acetylene through carbonylation. The method comprises steps as follows: acetylene, low-carbon alcohol and carbon monoxide are taken as raw materials and added to an organic solvent containing a nickel-based catalyst, low-carbon alcohol acrylate is directly synthesized from the mixture through carbonylation, whereinthe nickel-based catalyst comprises a main catalyst, an additive and a catalyst promoter, the main catalyst contains a nickel-containing compound and a multidentate ligand, the additive is triphenylphosphine, the chemical formula of the catalyst promoter is AlR(3-x)Clx, R is C2-C8 alkyl, and x is larger than or equal to 0 and smaller than or equal to 1. Compared with the prior art, the catalyticsystem is non-toxic and non-corrosion to equipment; yield of products at lower temperature and pressure is high, particularly, the catalyst system is low in cost and simple to prepare, cost of raw materials of production and operation cost can be greatly reduced, and the method has broad industrial application prospect.
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Paragraph 0039; 0040
(2018/05/30)
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- Synthesis of Esters by Functionalisation of CO2
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The invention relates to a method for (I) producing a carboxylic ester of formula (I). Said method comprises the steps of: a) bringing an organosilane/borane of formula Si or B into contact with CO2, in the presence of a catalyst and an electrophilic compound of formula (III), the groups R1, R2, R3, R4, R5, Y, and M′ being as defined in claim 1; and optionally b) recovering the compound of formula (I) produced.
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Paragraph 0130
(2017/09/06)
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- Synthesis, evaluation against Leishmania amazonensis and cytotoxicity assays in macrophages of sixteen new congeners Morita-Baylis-Hillman adducts
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We report the design, synthesis, in vitro evaluation against Leishmania amazonensis (IC50), cytotoxicity assays in macrophages (CC 50), and selectivity index (SICC50/IC50) of sixteen new congeners aromatic Morita-Baylis-Hillman adducts 1-16. The 1-16 were prepared in good to excellent yields (58%-97%) from the "one pot" Morita-Baylis-Hillman Reaction between the aldehydes 29-36 and the acrylates 27 or 28 under DABCO as promoter. The MBHA 2-[Hydroxy(2-nitrophenyl)propyl] propanoate (1, IC50 = 7.52 μg/mL or 28.38 μM; CC50 = 35.77 μg/mL or 134.98 μM; SI = 4.75) and 2-[Hydroxy(2-nitrophenyl) hydroxyethyl] propanoate (9, IC50 = 5.48 μg/mL or 20.52 μM; CC50 = 29.81 μg/mL or 111.64c μM and, SI = 5.43) were the most effective and safe evaluated compounds.
- Silva, Fabio P.L.,De Assis, Priscilla A.C.,Junior, Claudio G.L.,De Andrade, Natalia G.,Da Cunha, Saraghina M.D.,Oliveira, Marcia R.,Vasconcellos, Mario L.A.A.
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experimental part
p. 4295 - 4301
(2011/11/13)
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- Increased activity of enzymatic transacylation of acrylates through rational design of lipases
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A rational design approach was used to create the mutant Candida antarctica lipase B (CALB, also known as Pseudozyma antarctica lipase B) V190A having a kcat three times higher compared to that of the wild type (wt) enzyme for the transacylation of the industrially important compound methyl methacrylate. The enzymatic contribution to the transacylation of various acrylates and corresponding saturated esters was evaluated by comparing the reaction catalysed by CALB wt with the acid (H2SO4) catalysed reaction. The performances of CALB wt and mutants were compared to two other hydrolases, Humicola insolens cutinase and Rhizomucor mihei lipase. The low reaction rates of enzyme catalysed transacylation of acrylates were found to be caused mainly by electronic effects due to the double bond present in this class of molecules. The reduction in rate of enzyme catalysed transacylation of acrylates compared to that of the saturated ester methyl propionate was however less than what could be predicted from the energetic cost of breaking the π-system of acrylates solely. The nature and concentration of the acyl acceptor was found to have a profound effect on the reaction rate.
- Syren, Per-Olof,Lindgren, Ebba,Hoeffken, Hans Wolfgang,Branneby, Cecilia,Maurer, Steffen,Hauer, Bernhard,Hult, Karl
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experimental part
p. 3 - 10
(2011/02/22)
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- Substrate conformations set the rate of enzymatic acrylation by lipases
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Acrylates represent a class of α,β-unsaturated compounds of high industrial importance. We investigated the influence of substrate conformations on the experimentally determined reaction rates of the enzyme-catalysed transacylation of methyl acrylate and derivatives by ab initio DFT B3LYP calculations and molecular dynamics simulations. The results supported a least-motion mechanism upon the sp2 to sp3 substrate transition to reach the transition state in the enzyme active site. This was in accordance with our hypothesis that acrylates form productive transition states from their low-energy s-sis/s-trans conformations. Apparent kcat values were measured for Candida antarctica lipase B (CALB), Humicola insolens cutlnase and Rhizomucor miehei lipase and were compared to results from computer simulations. More potent enzymes for acryltransfer, such as the CALB mutant V190A and acrylates with higher turnover numbers, showed elevated populations of productive transition states.
- Syren, Per-Olof,Hult, Karl
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experimental part
p. 802 - 810
(2011/02/23)
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- Kinetics of the synthesis of propyl and butyl acrylates in the presence of some heteropolyacids as catalysts
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Esterification reactions of acrylic acid with n-propanol and n-butanol were carried out in the liquid phase in the presence of H3PW 12O40 or H3PMo12O40 as a catalyst, at various temperatures, molar ratios of the reactants, and concentrations of the catalyst. The kinetic equations had a nonelementary form.
- Skrzypek, Ierzy,Witczak, Teresa,Grzesik, MirosLaw,Witczak, Mariusz
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scheme or table
p. 12 - 17
(2009/04/07)
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- Asymmetric Diels-Alder reaction between acrylates and cyclopentadiene in the presence of chiral catalysts
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Asymmetric Diels-Alder reaction between cyclopentadiene and alkyl and cycloalkyl acrylates in the presence of new chiral catalysts, BBr 3?MentOEt, AlCl2OMent, BBr2OMent, and BBr(OMent)2, was studied. Optically active bicyclo[2.2.1]hept-2-ene- 5-carboxylates were synthesized. The influence of the reaction conditions on the total and optical yields and on the stereoselectivity of the adducts synthesized was examined. Nauka/Interperiodica 2006.
- Mamedov
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p. 1621 - 1625
(2008/02/07)
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- ZrOCl2·8H2O: An efficient, cheap and reusable catalyst for the esterification of acrylic acid and other carboxylic acids with equimolar amounts of alcohols
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Esterifications of carboxylic acids with equimolar amount of alcohols could be efficiently catalyzed by ZrOCl2·8H2O. Acrylate esters were obtained in good yields under solvent-free conditions at ambient temperature. The esterification of other carboxylic acids with alcohols also proceeded at ambient temperature or at 50°C to afford esters in high yields. If the esterification was performed in toluene under azeotropic reflux conditions to remove water, both the catalytic activity of ZrOCl 2·8H2O and the rate of esterification could be increased greatly. Furthermore, in the present catalytic system, the esters could be easily separated from the reaction mixtures and the catalyst could be easily recovered and reused.
- Sun, Hong-Bin,Hua, Ruimao,Yin, Yingwu
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p. 263 - 271
(2007/10/03)
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- PROCESS FOR THE CARBONYLATION OF AN ACETYLENICALLY UNSATURATED COMPOUND
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Process for the carbonylation of an acetylenically unsaturated compound by reaction with carbon monoxide and a co-reactant in the presence of a catalyst system based on (a) a source of platinum; (b) a source of anions and (c) a diphosphine of the following formula (1) R>P-R-PRR wherein R represents a covalent bridging group, R represents a bivalent radical that together with the phosphorus atom to which it is attached is an optionally substituted 2-phospha-tricyclo[3.3.1.1{3,7}]decyl group or a derivative thereof in which one or more of the carbon atoms are replaced by heteroatoms ("2-PA" group), and wherein R and R independently represent univalent radicals of up to 20 atoms or jointly form a bivalent radical of up to 20 atoms.
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- The effects of the carbonyl group in the cyclization of 1-hexenyl radicals
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The radical chain cyclization of allyl ether derivatives promoted by tosyl halides and light is suppressed by the presence of one carbonyl group conjugated with the double bond (acrylic double bond).
- Serra,Da Silva Correa,Do Vale
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p. 9463 - 9488
(2007/10/02)
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