Simple Chiral PyrrolidineâPyridine-Based Catalysts for Highly Enantioselective Michael Addition to Nitro Olefins
作者:Da-Zhen Xu、Sen Shi、Yongmei Wang
DOI:10.1002/ejoc.200900716
日期:2009.10
of chiral pyrrolidine–pyridine-based organocatalysts, available from commercially available starting materials, have been synthesized and shown to be very effective catalysts for the asymmetric Michaeladdition reactions of cyclic/acyclic/aromatic ketones and an aldehyde with nitro olefins, giving excellent yields (up to 99 %), diastereoselectivities (syn/anti = 99:1), and enantioselectivities (up
Pyrrolidine–pyridine base catalysts for the enantioselective Michael addition of ketones to chalcones
作者:Da-Zhen Xu、Sen Shi、Yingjun Liu、Yongmei Wang
DOI:10.1016/j.tet.2009.09.001
日期:2009.11
A series of pyrrolidine-pyridine base organocatalysts have been developed and 3a found to be a highly effective catalyst for the asymmetric Michael addition reactions of ketones to chalcones. The reaction generated the corresponding products 1, 5-diketones in excellent diastereoselectivities (up to >99:1 dr) and enantioselectivities (up to 100% ee). (c) 2009 Elsevier Ltd. All rights reserved.