Direct Mannich - Type Reactions Promoted by Frustrated Lewis Acid/Bronsted Base Catalysts

Direct Mannich-type reactions that afford both aand beta-amino esters by the reaction of a broad range of carbonyl compounds and aldimines are disclosed. The transformation is promoted by a sterically frustrated Lewis acid/Bronsted base pair, which is proposed to operate cooperatively: Within the catalyst complex, an enolate is generated that then reacts with a hydrogen-bond-activated imine. Noncovalent interactions between reactants and the catalyst provide selectivity and new opportunities for future catalyst design.