Rh^III-Catalyzed Synthesis of Cyclopenta[b]carbazoles via Cascade C–H/C–C Bond Cleavage and Cyclization Reactions: Using Amide as a Traceless Directing Group

Rhodium-catalyzed cascade C–H/C–C cleavage and cyclization reactions of 3-amide substituted indoles with diynes to construct cyclopenta­[b]­carbazoles have been developed. A strategy amide worked as a novel traceless directing group along with C–C bond cleavage via Friedel–Crafts-retro reaction has been disclosed in this protocol. This method exhibits a broad substrate scope and tolerates various functional groups, furnishing the carbazole derivatives in good to high yields.