Amide/Iminium Zwitterionic Catalysts for (Trans)esterification: Application in Biodiesel Synthesis
作者:Ying-Pong Lam、Xinyan Wang、Fei Tan、Wing-Hin Ng、Ying-Lung Steve Tse、Ying-Yeung Yeung
DOI:10.1021/acscatal.9b01959
日期:2019.9.6
organocatalysts based on an amide anion/iminium cation charge pair has been developed. The zwitterions are easily prepared by reacting aziridines with aminopyridines. They are catalytically applicable to transesterifications and dehydrative esterifications. Mechanistic studies reveal that the amide anion and iminium cation work synergistically in activating the reaction partners, with the iminium cationic
ZWITTERIONIC CATALYSTS FOR (TRANS)ESTERIFICATION: APPLICATION IN FLUOROINDOLE-DERIVATIVES AND BIODIESEL SYNTHESIS
申请人:The Chinese University of Hong Kong
公开号:US20210023539A1
公开(公告)日:2021-01-28
An amide/iminium zwitterion catalyst has a catalyst pocket size that promotes transesterification and dehydrative esterification. The amide/iminium zwitterions are easily prepared by reacting aziridines with aminopyridines. The reaction can be applied a wide variety of esterification processes including the large-scale synthesis of biodiesel. The amide/iminium zwitterions allow the avoidance of strongly basic or acidic condition and avoidance of metal contamination in the products. Reactions are carried out at ambient or only modestly elevated temperatures. The amide/iminium zwitterion catalyst is easily recycled and reactions proceed in high to quantitative yields.
Compounds of formula (I)
1
or pharmaceutically acceptable salts thereof are novel glucocorticoid receptor modulators and are useful for treating type II diabetes in a mammal.
PROCESS FOR DOUBLE CARBONYLATION OF ALLYL ALCOHOLS TO CORRESPONDING DIESTERS
申请人:EVONIK DEGUSSA GMBH
公开号:US20170174610A1
公开(公告)日:2017-06-22
The invention relates to a process for doubly carbonylating allyl alcohols to the corresponding diesters, wherein a linear or branched allyl alcohol is reacted with a linear or branched alkanol (alcohol) with supply of CO and in the presence of a catalytic system composed of a palladium complex and at least one organic phosphorus ligand and in the presence of a hydrogen halide selected from HCl, HBr and HI.
Selective monoetherification and monoesterificatton of diols and diacids under phase-transfer conditions
作者:Jaime de la Zerda、Gabriela Barak、Yoel Sasson
DOI:10.1016/0040-4020(89)80151-6
日期:1989.1
Research on the selectivity of etherlfication reactions of diols and esterification reactions of diacids by alkyl halides underphase-transfer catalysis has shown that under such conditions, selectivity of monoetherification increases in the order prim < sec < tert diols, though overall yield of monoether decreases from sec to tert diols. Monoesterification of diacids was accomplished with a high degree