Practical Synthesis of a 3,4,4a,5,8,8a- Hexahydro-2H-isoquinoline-1,6-dione Ring System by the Diels-Alder Reaction of an Optically Active Dienophile, a 5,6-Dihydro-1H-pyridin-2-one Derivative, with Siloxydiene

Abstract

An efficient method for preparing chiral 3-substituted-5, 6-dihydro-1H-pyridin-2-one (1) in large scale, based on a modification of our previous method, is described. The large scale Diels-Alder reaction of 1 with siloxydiene (2) to synthesize hexahydroisoquinoline-1, 6-dione, which is a key intermediate for the synthesis of manzamine alkaloids, was also studied.