Cu-catalyzed Cascade Cyclization of Isothiocyanates, Alkynes, and Diaryliodonium Salts: Access to Diversely Functionalized Quinolines.

Herein, we report a copper-catalyzed novel, highly efficient, and modular cascade annulation reaction for the synthesis of quinoline derivatives starting from easily available alkynes, isothiocyanates, and diaryliodonium salts. The reaction displayed excellent regioselectivities, when unsymmetrical alkynes were employed as partners, giving access to diversely functionalized quinolines in good to excellent yields for a wide range of functional groups.