Electrochemical Radical Tandem Difluoroethylation/Cyclization of Unsaturated Amides to Access MeCF₂-Featured Indolo/Benzoimidazo [2,1-<i>a</i>]Isoquinolin-6(5<i>H</i>)-ones

Abstract

A metal-free electrochemical oxidative difluoroethylation of 2-arylbenzimidazoles was accomplished, which provided an efficient strategy for the synthesis of MeCF2-containing benzo[4,5]imidazo[2,1-a]-isoquinolin-6(5H)-ones. In addition, the method also enabled the efficient construction of various difluoroethylated indolo[2,1-a]isoquinolin-6(5H)-ones. Notably, this electrochemical synthesis protocol proceeded well under mild conditions without metal catalysts or exogenous additives/oxidants added.

Keywords

• electrochemical synthesis
• difluoroethylation
• radical
• polycyclic compounds
• tandem cyclization