Bronsted acid-catalyzed, enantioselective, vinylogous Mannich reaction of vinylketene silyl N,O-acetals

Vinylketene silyl N,O-acetals undergo chiral phosphoric acid-catalyzed, vinylogous Mukaiyama-Mannich reactions with imines and afford delta-amino-alpha,beta-unsaturated amides in typically good yields, complete gamma-regioselectivity, and up to 92% ee with catalyst loadings of as low as 1 mol %. The Mannich products can be readily manipulated to furnish valuable synthetic intermediates.