Solvent-controlled selective synthesis of quinazolinones and 2-arylquinazolinones via copper-catalyzed [5 + 1] annulation

Abstract

A copper-catalyzed cyclization for the selective synthesis of quinazolinones and 2-arylquinazolinones depending on solvent control has been established. o-Aminobenzamide is employed as an unprecedented C1 source involving in the [5 + 1] annulation to form 2-arylquinazolinones via double C–N bonds cleavage in Cu/DMSO system. While adjusting the solvent to MeOH achieves quinazolinones in high yields. Furthermore, the gram-scalable assembly and late-stage transformations of quinazolines demonstrate significant synthetic applications of this method.