Rhodium-catalyzed Oxidative Coupling/Cyclization of Benzamides with Alkynes via C-H Bond Cleavage

Oxidative coupling of primary, secondary, and tertiary benzamides with internal alkynes proceeds efficiently under rhodium catalysis to selectively give the corresponding 1:1 and 1:2 coupling products, accompanied by C H and/or N-H bond cleavages. Some of the products exhibit intense fluorescence in the solid state.