Organocatalyzed Highly Enantioselective and anti-Selective Construction of γ-Butenolides through Vinylogous Mukaiyama Aldol Reaction
作者:Ning Zhu、Bao-Chun Ma、Yong Zhang、Wei Wang
DOI:10.1002/adsc.201000099
日期:——
The formation of chiral γ‐butenolides has been achieved with good yields (up to 90%), high enantioselectivity (up to 91%) and diastereoselectivity (up to 9/1, anti‐selective) through an organocatalyzed vinylogous Mukaiyamaaldolreaction of 2‐(trimethylsilyloxy)furan and aldehydes. A wide range of chiral γ‐butenolides was obtained under mild conditions by this methodology.
The asymmetricdirect vinylogous aldolreaction of unactivated γ-butenolide with aldehydes has been developed, giving the corresponding 5-(1′-hydroxy)butenolide derivatives in high yields (up to 93%) and enantioselectivities (up to 83% ee) under mild conditions.
Asymmetric Vinylogous Aldol Reaction of Silyloxy Furans with a Chiral Organic Salt
作者:Ravi P. Singh、Bruce M. Foxman、Li Deng
DOI:10.1021/ja103331t
日期:2010.7.21
significance there is a general lack of asymmetric vinylogous aldolreactions that tolerate variations of both the silyloxy furans and aldehydes. We have developed a newchiral organic catalyst based on a carboxylate-ammonium salt preparedfrom a thiourea-amine and a carboxylic acid. This newcatalyst enabled us to develop an efficient asymmetric vinylogous aldolreaction of unprecedented scope with respect