Deciphering Asymmetric Brønsted Base-Aminocatalytic Mode in Pudovik/[1,2]-Phospha-Brook Rearrangement/Michael Cascade Reaction

Abstract

An approach involving the use of a bifunctional aminocatalyst containing Brønsted base and iminium activation sites for asymmetric multicomponent reactions involving [1,2]-phospha-Brook rearrangement has yet to be realized. Herein, we present an aminocatalytic enantioselective conjugate addition of α-phosphonyloxy enolates formed via [1,2]-phospha-Brook rearrangement to α,β-unsaturated ketones. The methodology unfolds a simple one-pot operation consisting of a robust additive-free catalytic system providing a series of oxindole derivatives having two contiguous stereocenters in high yields with excellent stereoselectivities.