[EN] ASYMMETRIC MICHAEL AND ALDOL ADDITION USING BIFUNCTIONAL CINCHONA-ALKALOID-BASED CATALYSTS<br/>[FR] ADDITIONS ASYMETRIQUES DE MICHAEL ET D'ALDOL UTILISANT DES CATALYSEURS BIFONCTIONNELS A BASE DE CINCHONINE
申请人:UNIV BRANDEIS
公开号:WO2005121137A1
公开(公告)日:2005-12-22
One aspect of the present invention relates to quinine-based and quinidine-based catalysts. Another aspect of the invention relates to a method of preparing a derivatized quinine-based or quinidine-based catalyst comprising 1) reacting quinine or quinidine with 5 base and a compound that has a suitable leaving group, and 2) converting the ring methoxy group to a hydroxy group. Another aspect of the present invention relates to a method of preparing a chiral, non-racemic compound from a prochiral electron-deficient alkene or azo compound or prochiral aldehyde or prochiral ketone, comprising the step of: reacting a prochiral electron-deficient alkene or azo compound or prochiral aldehyde or prochiral 10 ketone with a nucleophile in the presence of a catalyst; thereby producing a chiral, non racemic compound; wherein said catalyst is a derivatized quinine or quinidine. Another aspect of the present invention relates to a method of kinetic resolution, comprising the step of reacting racemic chiral alkene with a nucleophile in the presence of a derivatized quinine or quinidine.
progress has been made toward the development of metal-free catalysts of enantioselective transformations, yet the discovery of organic catalysts effective at low catalyst loadings remains a major challenge. Here we report a novel synergistic catalyst combination system consisting of a peptide-inspired chiral helical (thio)urea oligomer and a simple tertiary amine that is able to promote the Michael reaction
Multisiteorganic–inorganichybridcatalysts have been prepared and applied in a new general, practical, and sustainable synthetic procedure toward industrially relevant GABA derivatives. The domino sequence is composed of seven chemical transformations which are performed in two one‐pot reactions. The method produces both enantiomeric forms of the product in high enantiopurity as well as the racemate
Highly Enantioselective Michael
Addition of Malonates to Nitroolefins Catalyzed by Chiral
Bifunctional Tertiary Amine-Thioureas Based on Saccharides
作者:Jun-An Ma、Xiao-Juan Li、Kun Liu、Hai Ma、Jing Nie
DOI:10.1055/s-0028-1087370
日期:——
A series of saccharide-derived bifunctional tertiary amine-thioureas for the asymmetric Michaeladdition reaction have been designed and synthesized. The addition products between malonates and various nitroolefins were obtained in high yields (up to 99%) and excellentenantioselectivities (up to 99% ee).