Chalcogen functionalized pyrimidine synthesis by three-component free radical chalcogenation and pyrimidine ring construction

Abstract

A rather facile transition metal-free protocol for the synthesis of chalcogen functionalized pyrimidines has been established via three-component reactions of enaminones, disulfides/diselenide, and amidines/guanidine. The reactions proceed efficiently in the presence of I₂/KOH and smoothly provide chalcogenated pyrimidines with a broad substrate scope. The reaction mechanism involves a key chalcogen (sulfur)-centered free radical, which has been verified by control experiments.