Brønsted Acid-Catalyzed Synthesis of Benzo[f]indole and Naphtho[2,3-b]furan Derivatives via an Intramolecular Cascade Isomerization/Cyclisation/Aromatization

Abstract

Herein, we demonstrated a PTSA-catalyzed facile and efficient synthesis of tricyclic benzo[f]indole and naphtho[2,3-b]furan derivatives via a cascade isomerization/cyclisation/Aromatisation reaction in good yields. This protocol offers several advantages, including ease of preparation of substrate, metal free reaction conditions, broad functional group tolerance, mild reaction conditions, and a wide range of substrate scope.