Proline-based reduced dipeptides as recyclable and highly enantioselective organocatalysts for asymmetric Michael addition
作者:Xiaohui Cao、Ge Wang、Richeng Zhang、Yingying Wei、Wei Wang、Huichao Sun、Ligong Chen
DOI:10.1039/c1ob05679d
日期:——
A series of novel proline-based reduced dipeptides was developed and evaluated for a direct Michael addition of ketones and aldehydes to nitroalkenes. Excellent yields (up to 95%), diastereoselectivities (up to 98% dr) and enantioselectivities (up to 98% ee) were achieved in the presence of 5 mol% catalyst without any additional additives at room temperature.
开发了一系列基于脯氨酸的新型还原二肽,并评估了将酮和醛直接迈克尔加成到硝基烯烃中的能力。在室温下,在没有任何其他添加剂的情况下,在5摩尔%的催化剂存在下,可获得优异的收率(高达95%),非对映选择性(高达98%dr)和对映选择性(高达98%ee)。