Organocatalytic Enantioselective One-Pot Four-Component Ugi-Type Multicomponent Reaction for the Synthesis of Epoxy-tetrahydropyrrolo[3,4-b]pyridin-5-ones.
Résumé
Enantioselective multicomponent reaction: In the presence of a catalytic amount of chiral BINOL-derived phosphoric acid (TRIP), the reaction of an α-isocyanoacetate 1, an aldehyde 2, and an aniline 3, followed by addition of a toluene solution of α,β-unsaturated acyl chloride 4 afforded the oxa-bridged tricycle 5 in excellent yield, diastereoselectivity, and enantioselectivity. Six chemical bonds, five stereogenic centers, and three cycles were formed in this one-pot four-component reaction.