An Oxidative [3+2+1] Cyclization of Enaminones and N‐Alkenyl‐2‐pyrrolidinone: Access to Polysubstituted 4‐Alkylated 1,4‐dihydropyridines

Abstract

AbstractAn oxidative [3+2+1] cyclization of enaminones and N‐alkenyl‐2‐pyrrolidinone is described for the synthesis of 4‐alkylated 1,4‐dihydropyridines (1,4‐DHPs). By using terminal olefin as the C4 source of the 1,4‐DHP skeleton, this synthetic strategy provides a series of 1,4‐DHPs through a 1,1‐difunctionalization/cyclization process. In this protocol, two C(sp3)−C(sp2) bonds and a C(sp2)−N bond are simultaneously formed, the hydrogen source on the newly formed methyl group of the 1,4‐DHP skeleton is confirmed and a possible mechanism is proposed.magnified image