Electrochemical Radical Tandem Difluoroethylation/Cyclization of Unsaturated Amides to Access MeCF-Featured Indolo/Benzoimidazo [2,1-]Isoquinolin-6(5)-ones.

A metal-free electrochemical oxidative difluoroethylation of 2-arylbenzimidazoles was accomplished, which provided an efficient strategy for the synthesis of MeCF-containing benzo[4,5]imidazo[2,1-]-isoquinolin-6(5)-ones. In addition, the method also enabled the efficient construction of various difluoroethylated indolo[2,1-]isoquinolin-6(5)-ones. Notably, this electrochemical synthesis protocol proceeded well under mild conditions without metal catalysts or exogenous additives/oxidants added.