A CHIRAL FORMAMIDE - DESIGN AND APPLICATION TO CATALYTIC ASYMMETRIC-SYNTHESIS

(S,S)-N,N-Bis(-alpha-methylbenzyl)formamide is the first example of ch iral formamides that function as Lewis base catalysts to effectively s erve catalytic asymmetric synthesis. The chiral formamide in combinati on with an additive, HMPA, catalyzes allylations of aliphatic aldehyde s with allyl- and crotyltrichlorosilanes with high enantioselectivity (up to 98% ee). In the crotylations with (E)-crotyltrichlorosilane, cy clohexanecarboxaldehyde and hydrocinnamaldehyde gave the corresponding anti homoallylic alcohols exclusively with 98 and 94% ee's, respectiv ely. (C) 1998 Elsevier Science Ltd, All rights reserved.