Enantioselective Vinylogous Michael/Cyclization Cascade Reaction of Acyclic beta,gamma-Unsaturated Amides with Isatylidene Malononitriles: Asymmetric Construction of Spirocyclic Oxindoles

摘要

The first direct and enantioselective vinylogous Michael/cyclization cascade reaction between acyclic beta,gamma-unsaturated amides and isatvlidene malononitriles has been developed. Optically active spirocyclic oxindoles have been obtained in good-to-excellent yields (84-96%) and enantioselectivity (79-97% ee) in the presence of 2 mol% (DHQD)(2)PYR [2,5-dipheny1-4,6-bis(9-O-dihydroquinyl)pyrimidine.]