C3-Symmetrical Cinchonine-Squaramide as New Highly Efficient, and Recyclable Organocatalyst for Enantioselective Michael Addition
作者:Chang Min、Xin Han、Zongquan Liao、Xiangfei Wu、Hai-Bing Zhou、Chune Dong
DOI:10.1002/adsc.201100066
日期:2011.10
A novel and recyclable catalyst, a C3-symmetrical cinchonine-squaramide, has been developed for the asymmetric Michael addition of 1,3-dicarbonyl compounds to nitroalkenes. When using only 1 mol% of catalyst 1a for the reaction, high reaction yields with excellent enantioselectivities and diastereoselectivities (up to 96% yield,>99% ee,>99:1 dr) were achieved, in which the results for cyclic keto esters
已经开发出一种新颖的可循环使用的催化剂,C 3对称的金鸡宁-方酸酰胺,用于将1,3-二羰基化合物不对称地迈克尔加成到硝基烯烃上。当仅使用1 mol%的催化剂1a进行反应时,可获得高的反应产率,同时具有出色的对映选择性和非对映选择性(最高96%收率,> 99%ee,> 99:1 dr),其中环状酮酯的结果是有史以来最好的。而且,1a可以通过简单的沉淀容易地回收,并且在不损失任何选择性和活性的情况下用于六个循环。