Enantioselective Nitroaldol Reaction Catalyzed by Sterically Modified Salen-Chromium Complexes

A group of modified (salen)Cr(III)Cl complexes with bulky benzylic substituents in the 3,3'-position of the salicylidene moiety have been successfully applied for the asymmetric nitroaldol reaction. The readily accessible complex bearing 3-phenylpent-3-yl groups (2 mol %) leads to beta-nitro alcohols ill Lip to 92% yield and 94% ee.