Copper(0)/Selectfluor System-Catalyzed Tandem Annulation/Aromatization ofo-Aryl Benzenesulfonylimides:A Facile Synthesis of 6H-Phenanthridines

Abstract

A facile and efficient method for the synthesis of 6H-phenanthridines has been successfully developed involving a copper(0)/Selectfluor system-catalyzed tandem annulation/aromatization of o-aryl benzenesulfonylimides. A variety of substituted 6H-phenanthridines were synthesized in moderate to good yields under mild reaction conditions. Mechanistic experiments revealed that the reaction might involve an oxycupration of C＝N bond followed by an intramolecular C-H bond amination as the key steps triggered by an in situ generated copper species XCuOH (X＝F or BF 4) from the Cu(0)/Selectfluor system.