Rh(III)‐Catalyzed [4+2] Cyclization of 2‐Aryl‐1H‐benzo[d]imidazoles with Maleimides via C‐H Activation

A rhodium‐catalyzed formal [4+2]‐cyclization of 2‐aryl‐1H‐benzo[d]imidazoles with maleimides through C−H bond activation process is described here. Such an approach enables selectively construct a series of functionalized cis‐dihydro‐benzimidazo[2,1‐a]isoquinolines. The reaction features a broad substrate scope with respect to both coupling components, and the desired products were obtained with up to 85 % yields. Herein we described a rhodium‐catalyzed formal [4+2]‐cyclization of 2‐aryl‐1H‐benzo[d]imidazoles with maleimides through C−H bond activation process to selectively construct a series of functionalized cis‐dihydro‐benzimidazo[2,1‐a]isoquinolines. The reaction features a broad substrate scope.