Rh(III)‐Catalyzed C‐H Cyclization of 2‐Arylbenzimidazoles with CF3‐Imidoyl Sulfoxonium Ylides and Further Sc(III)‐Catalyzed Deaminative Hydroxylation

An efficient Rh(III)‐catalyzed C‐H bond activation/cyclization of 2‐arylbenzimidazoles with CF3‐imidoyl sulfoxonium ylides has been achieved, yielding diverse CF3‐ and amino‐disubstituted 5,6‐dihydrobenzoimidazo[2,1‐a]isoquinolines, which could undergo a deaminative hydroxylation to access CF3‐ and hydroxy‐disubstituted 5,6‐dihydrobenzoimidazo[2,1‐a]isoquinolines under Sc(OTf)3 catalyst. This developed strategy features easily available starting materials, broad substrate scope, ready scalability and high efficiency. Moreover, the antitumor activities of selected products against some human cancer cell lines were also investigated, and the results indicated that several products show the effective antiproliferative activities.