14035-94-0Relevant academic research and scientific papers
A general platinum-catalyzed alkoxycarbonylation of olefins
Beller, Matthias,Dühren, Ricarda,Franke, Robert,Ge, Yao,Huang, Weiheng,Jackstell, Ralf,Liu, Jiawang,Neumann, Helfried,Schneider, Carolin,Yang, Ji
supporting information, p. 5235 - 5238 (2020/07/30)
Hydroxy- and alkoxycarbonylation reactions constitute important industrial processes in homogeneous catalysis. Nowadays, palladium complexes constitute state-of-the-art catalysts for these transformations. Herein, we report the first efficient platinum-catalysed alkoxycarbonylations of olefins including sterically hindered and functionalized ones. This atom-efficient catalytic transformation provides straightforward access to a variety of valuable esters in good to excellent yields and often with high selectivities. In kinetic experiments the activities of Pd- and Pt-based catalysts were compared. Even at low catalyst loading, Pt shows high catalytic activity.
Method used for synthesis of 2-methylpentanedioic acid dimethyl ester
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Paragraph 0037; 0043; 0044; 0050; 0051; 0057, (2019/06/30)
The invention provides a method used for synthesis of 2-methylpentanedioic acid dimethyl ester. The method used for synthesis of 2-methylpentanedioic acid dimethyl ester comprises following steps: 2-methyl pentanedinitrile is mixed with an acid, hydrolysis reaction is carried out, an obtained product is allowed to stand so as to obtain an upper layer oil phase and a lower layer water phase; the oil phase and the water phase are separated; the oil phase is mixed with methanol for esterification reaction so as to obtain 2-methylpentanedioic acid dimethyl ester. Operation of the method is simple;technology route is short; raw material consumption is low; and no waste gas, waste water, or waste residue is generated.
ORGANIC ACIDS FROM HOMOCITRATE AND HOMOCITRATE DERIVATIVES
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Page/Page column 32, (2016/01/01)
This disclosure relates to methods for converting homocitric acid to adipic acid, and more particularly to methods of using metal catalysts to catalyze the conversion of homocitric acid to adipic acid.
Synthesis of dimethyl glutarate from cyclobutanone and dimethyl carbonate over solid base catalysts
Zhi, Chen,Dudu, Wu
experimental part, p. 1834 - 1838 (2012/07/31)
A facile route for the synthesis of dimethyl glutarate (DMG) from cyclobutanone and dimethyl carbonate (DMC) in the presence of solid base catalysts has been developed. It was found that the intermediate carbomethoxycyclobutanone (CMCB) was produced from cyclobutanone with DMC in the first step, and then CMCB was further converted to DMG by reacting with a methoxide group. The role of the basic catalysts can be mainly ascribed to the activation of cyclobutanone via the abstraction of a proton in the α-position by base sites, and solid bases with moderate strength, such as MgO, favor the formation of DMG.
"Cofactor"-controlled enantioselective catalysis
Dydio, Pawel,Rubay, Christophe,Gadzikwa, Tendai,Lutz, Martin,Reek, Joost N. H.
supporting information; experimental part, p. 17176 - 17179 (2011/12/13)
We report an achiral bisphosphine rhodium complex equipped with a binding site for the recognition of chiral anion guests. Upon binding small chiral guests-cofactors-the rhodium complex becomes chiral and can thus be used for asymmetric catalysis. Screening of a library of cofactors revealed that the best cofactors lead to hydrogenation catalysts that form the products with high enantioselectivity (ee?s up to 99%). Interestingly, a competition experiment shows that even in a mixture of 12 cofactors high ee is obtained, indicating that the complex based on the best cofactor dominates the catalysis.
CONVERSION OF NITRILE COMPOUNDS INTO CORRESPONDING CARBOXYLIC ACIDS AND ESTERS
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Page/Page column 3, (2010/06/19)
Hydrocarbon compounds having at least one nitrile function are converted into compounds having at least one carboxylic function by hydrating the nitrile functions into amide functions by reaction with water in the presence of a strong inorganic acid, and then hydrolyzing the amide functions into carboxylic functions by reaction with water and a strong inorganic acid; the carboxylic compounds thus obtained can be esterified into diesters, advantageously diester solvents.
Process for the carbonylation of conjugated dienes
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Page column 7,8, (2008/06/13)
The present invention relates to a process for the carbonylation of conjugated dienes, whereby a conjugated diene is reacted with carbon monoxide and a hydroxyl group containing compound in the presence of a catalyst system including: (a) a source of palladium cations, (b) a phosphorus-containing ligand, (c) a source of anions, wherein the phosphorus-containing ligand is a ligand having the general formula (I): X1—R—X2 wherein X1 and X2 represent a substituted or non-substituted cyclic group with at least 5 ring atoms, of which one is a phosphorus atom, and R represents a bivalent organic bridging group, connecting both phosphorus atoms, containing from 1 to 4 atoms in the bridge, whereby the carbonylation process can be performed batch wise, semi-continuously or continuously.
1,3-Stereoinduction in radical reactions: Radical additions to dialkyl 2-alkyl-4-methyleneglutarates
Hayen,Koch,Saak,Haase,Metzger
, p. 12458 - 12468 (2007/10/03)
Tin hydride-mediated radical additions to a series of α-methylene-glutarates 1, furnishing 2;4-dialkyl-substituted glutarates 3 are reported. The diastereoselectivity of hydrogen transfer to the intermediate adduct radicals 2, possessing a stereogenic center in γ-position, was disappointing in the temperature range of -78 to 80 °C. However, the reactions proved to be able to proceed with excellent 1,3-diastereoselectivities under chelation-controlled conditions, depending on the steric impacts of 2- and 4-alkyl substituents as well as on the ester-alkyl moiety and choice of Lewis acid. Using MgBr2·OEt2 as additive, syn-selectivities of 98:2 were achieved upon initial tert-butyl radical addition at -78 °C. High anti-diastereoselectivities were observed in the MgBr2·OEt2-controlled pathway at 70 °C when smaller alkyl radicals such as cyclohexyl, ethyl, and methyl were applied. Interesting and uncommon temperature dependences were observed in the temperature range of -78 to 100 °C, revealing strong entropic effects in the transition states. A model that accounts for the opposed stereochemical outcomes under chelation-controlled conditions is presented.
Clay Montmorillonite: An Efficient Heterogeneous Catalyst for Michael Reactions of Silyl Ketene Acetals and Silyl Enol Ethers with α,β-Unsaturated Carbonyl Compounds
Kawai, Motomitsu,Onaka, Makoto,Izumi, Yusuke
, p. 2157 - 2164 (2007/10/02)
The Michael addition of silyl ketene acetals to α,β-unsaturated esters (enoates) is investigated.The reaction is catalyzed by clay montmorillonite (solid acid) most effectively among various, homogeneous and heterogeneous acid promoters.The montmorillonite-catalyzed reaction has several prominent features: (1) Not only α- or β-monosubstituted acrylates but also α,β- or β,β-disubstituted acrylates are applicable. (2) The highly regioselective 1,4-addition to a polyenoate is achievable. (3) The michael adduct can be obtained in the form of a labile silyl ketene acetal owing to a simple work-up procedure.The Michael reaction of a silyl enol ether and silyl ketene acetals with α,β-unsaturated ketones (enones) is also described.
Applications of Homogeneous Water-gas Shift Reaction. IV. Hydrocarbonylation and Dimerization of Methyl Acrylate with CO and H2O
Murata, Kazuhisa,Matsuda, Akio
, p. 2195 - 2199 (2007/10/02)
Hydrocarbonylation of methyl acrylate with CO and H2O forms dimethyl 4-oxopimelate in 94percent yield based on H2O, the Co2(CO)8-1,2-bis(diphenylphosphino)ethane (diphos) catalyst system being used as in the case of ethylene or propylene.Increasing temperature tends to promote the dimerization and/or hydrodimerization of methyl acrylate to give 1,3-bis(methoxycarbonyl)-1-butene and/or dimethyl-2-methylglutarate.Effects of CO pressure and H2O concentration on the hydrocarbonylation and dimerization were examined at 135 and 165 deg C.Catalytically active intermediates for the hydrocarbonylation take part in the dimerization of methyl acrylate.
