Facile synthesis of indolo[3,2-a]carbazoles via Pd-catalyzed twofold oxidative cyclization

Abstract

A rapid and efficient route has been developed for the synthesis of 9-methoxycarbonylindolo[3,2-a]carbazole derivatives. The key steps in this approach involved an aromatic amination and an oxidative biaryl coupling. Via the present route, indolo[3,2-a]carbazole derivatives are available in 3–4 steps based on commercially available starting materials.

Keywords

• cyclization
• indolo[3,2-a]carbazole
• N-arylation
• oxidative biaryl coupling
• palladium catalysis