Diastereoselective Synthesis of <font>γ</font>-Butenolides Catalyzed by Potassium <i>tert</i>-Butoxide
作者:Guang-Fen Du、Lin He、Cheng-Zhi Gu、Bin Dai
DOI:10.1080/00397911.2010.538888
日期:2012.4.15
Abstract Potassiumtert-butoxide (0.1 mol%) catalyzed a vinylogous Mukaiyama aldol reaction between aromatic and aliphatic aldehydes with 2-(trimethylsilyloxy)furan. The corresponding γ-butenolides were obtained in good yields with good diastereoselectivities. GRAPHICAL ABSTRACT
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.
diastereoselective vinylogous Mukaiyama aldol reaction is reported, between pyrrole/furan-based dienoxy silanes and aromatic aldehydes on salty water/methanol medium, at almost human body temperature, under ultrasonic irradiation. With pyrrole dienes the reaction is anti-selective, while that of furandienes is syn-selective. The dual role of water as both reaction medium and promoter is highlighted.