Condition-Controlled Rh(III)-Catalyzed Chemodivergent Cyclization of 2-Arylpyridines with CF3-Imidoyl Sulfoxonium Ylides via Triple C–H Activation

A condition-controlled Rh(III)-catalyzed selective synthesis of CF₃-substituted indoles and pyrido[2,1-a]isoindoles from 2-arylpyridines and CF₃-imidoyl sulfoxonium ylides has been developed. The Cp*Rh(MeCN)₃(SbF₆)₂/HFIP system afforded CF₃-substituted indoles via triple C-H activation, while the [Cp*RhCl₂]₂/MeCN condition selectively furnished CF₃-substituted pyrido[2,1-a]isoindoles through C-H [4 + 1] annulation. The notable advantages of this developed method included readily available starting materials, broad substrate scope, and excellent chemoselectivity. Importantly, several selected products showed promising antitumor activities.