Mixed La−Li Heterobimetallic Complexes for Tertiary Nitroaldol Resolution

A kinetic resolution of tertiary nitroaldols derived from simple ketones is described. Mixed BINOL/biphenol La−Li heterobimetallic complexes gave the best selectivity in retro-nitroaldol reactions of racemic tertiary nitroaldols. By using a mixture of La−Li3−(1a)3 complex (LLB 2a) and La−Li3−(1b)3 (LLB* 2b) complex in a ratio of 2/1, chiral tertiary nitroaldols were obtained in 80−97% ee and 30−47% recovery yield.