Synthesis of Difluoroarymethyl-Substituted Benzimidazo[2,1- a ]isoquinolin-6(5 H )-ones under Mild Conditions.

A highly efficient method for synthesis of difluoroarymethyl-substituted benzimidazo[2,1- a ]isoquinolin-6(5 H )-ones using 2-arylbenzoimidazoles with α,α-difluorophenylacetic acid as reaction substrates has been developed through radical cascade cyclization. The advantage of this strategy lies in excellent functional group tolerance to generate the corresponding products in good yields under base- and metal-free conditions.