A NEW SYNTHESIS OF DIHYDROPYRIDIN-2-ONES FROM BRASSARD'S DIENE AND IMINES

摘要

A new method for the synthesis of dihydropyridin-2-ones from various N-2-nitrobenzenesulfonyl (nosyl) imines and 1,3-diethoxy-1-trimethylsiloxy-1,3-butadiene (Brassard's diene) under weakly-basic conditions is described. This synthesis of dihydropyridin-2-ones involves the initial addition reaction of Brassard's diene to imines to afford the adducts followed by a cyclization reaction that forms the corresponding 4-ethoxy-5,6-dihydro-1H-pyridin-2-ones in moderate to good yields after deprotection of its nosyl group from the adducts.