Zwitterion enhanced performance in palladium–phosphine catalyzed ethylene methoxycarbonylation
摘要:
Zwitterions were used for the first time as promoters in ethylene methoxycarbonylation for the production of methyl propionate. They were found to improve the catalytic performance of the Pd-phosphine system. The presence of zwitterions could contribute to stabilize transition states and active catalytic Pd intermediates. The beneficial effect of the zwitterions was found to be most pronounced, when low amount of a strong acid (MeSO3H) was used with respect to palladium (below 2 equiv.). Under these conditions, phosphine ligand alkylation and reaction vessel corrosion are also anticipated to be less severe. (C) 2013 Elsevier B.V. All rights reserved.
An Efficient Method for Chemoselective Thioacetalization of Aldehydes in the Presence of a Catalytic Amount of Acidic Ionic Liquid under Solvent-Free Conditions
作者:Abdol Hajipour、Ghobad Azizi、Arnold Ruoho
DOI:10.1055/s-0029-1217550
日期:2009.7
A water-stable Brønsted acidic ionic liquid with an alkane sulfonic acid group was synthesized. This ionic liquid catalyzed the thioacetalization reaction smoothly to afford 1,3-dithianes in excellent yield and less time. In this article we describe a mild and chemoselective thioacetalization procedure for the protection of various aldehydes in the presence of catalytic amount of ionic liquid (2 mol%).
Pd-catalyzed ethylene methoxycarbonylation with Brønsted acid ionic liquids as promoter and phase-separable reaction media
作者:Eduardo J. García-Suárez、Santosh G. Khokarale、Olivier N. van Buu、Rasmus Fehrmann、Anders Riisager
DOI:10.1039/c3gc41380b
日期:——
Brønsted acid ionic liquids (BAILs) were prepared and applied as combined acidpromoters and reaction media in Pd–phosphine catalyzed methoxycarbonylation of ethylene to produce methyl propionate. The BAILs served as alternatives to common mineral acids required for the reaction, e.g. methanesulfonic acid or sulfuric acid, resulting in high catalytic activity and selectivity towards methyl propionate
Acidic ionic liquids and green and recyclable catalysts in the clean nitration of TAIW to CL-20 using HNO<sub>3</sub> electrolyte
作者:Wang Kai、Bo Dong、Chao-fei Yang、Hua Qian
DOI:10.1139/cjc-2016-0512
日期:2017.2
and the result was encouraging. A series of SO3H-functionalized ionic liquids were utilized to further improve the result. The satisfactory yield of CL-20 (94%) makes it a useful method for the green and clean synthesis of CL-20.
A two-phase system for the clean and high yield synthesis of furylmethane derivatives over –SO<sub>3</sub>H functionalized ionic liquids
作者:S. H. Shinde、C. V. Rode
DOI:10.1039/c7gc01654a
日期:——
respective ionic liquids. Among the several preapered ionic liquids, strong acidic imidazolium based butylsulfonic acid (6) showed the best activity with a maximum of 84% yield of condensation product. This strategy offers significantly highyield production of condensation products of furan and furfural as compared to the traditional mineral acid route. The activity and stability of the -SO3H functionalized