Pentafluorophenol-Catalyzed Metal-Free Fischer Indole Synthesis: A Novel Approach to Carbazole Derivatives and Desbromoarborescidine A.

Carbazoles represent significant heterocyclic compounds with a wide range of applications in organic synthesis. Conventional techniques, such as the Fischer indole synthesis, have been extensively utilized for the construction of these structures. In this study, we report the first use of pentafluorophenol (PFP) as a catalyst in a metal-free approach for the synthesis of carbazoles.