Substrate-controlled diastereoselectivity switch in catalytic asymmetric direct mannich reaction of glycine derivatives with imines: from anti- to syn-α,β-diamino acids

Abstract

(Chemical equation Presented) Back and forth: A diastereoselectivity switch has been devised in the Fesulphos-CuI-catalyzed glycine direct Mannich reaction with N-(8-quinolyl)sulfonyl imines by tuning the steric and electronic properties of the glycine component (see scheme). αβ-Diamino acids of syn configuration are produced under high diastereo- and enantiocontrol with glycinate esters derived from electron-deficient benzophenonetype ketimines, in contrast to aldiminederived pronucleophiles that lead to anti-configured products. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.