Development of the first Bronsted acid assisted enantioselective Bronsted acid catalyzed direct Mannich reaction

We here describe the development of the first enantioselective Bronsted acid assisted chiral Bronsted acid catalyzed direct Mannich reaction of acetophenone with various aldimines. The re-action proceeds in the presence of a chiral and an achiral Bronsted acid which simultaneously activate the ketone and aldimine to give the corresponding beta-amino ketones with good enantioselectivities and without the necessity of enolate preformation.