Mixed La-Li heterobimetallic complexes for tertiary nitroaldol resolution

Full details of the kinetic resolution of tertiary nitroaldols derived from simple ketones are described. Mixed BINOL/biphenol La-Li heterobimetallic complexes gave the best selectivity in retro-nitroaldol reactions of racemic tertiary nitroaldols. Using a 2:1 mixture of La-Li3-(binaphthoxide 1a)3 complex (LLB) and La-Li3-(biphenoxide 1e)3 complex, chiral tertiary nitroaldols were obtained in 80-97% ee and 30-47% recovery yield. Transformations of products were also investigated.