Visible-light-driven cascade radical cyclization toward the synthesis of α-carbonyl alkyl-substituted benzimidazo[2,1-<i>a</i>]isoquinolin-6(5<i>H</i>)-one derivatives

Abstract

A visible-light-driven cascade radical cyclization process of <i>N</i>-methacryloyl-2-phenylbenzimidazole has been established with α-carbonyl alkyl bromide. This protocol provides an efficient and practical method for the synthesis of various α-carbonyl alkyl-substituted benzimidazo[2,1-<i>α</i>]isoquinolin-6(5<i>H</i>)-ones in outstanding yields, mild reaction conditions and excellent functional group tolerance.