One‐Pot Synthesis of Pyrrolo[1,2‐f]phenanthridines From 1‐Arylpyrroles via Successive Palladium‐Catalyzed Direct Arylations

Abstract

AbstractA Pd‐catalyzed annulative π‐extension reaction of 1‐arylpyrroles using 1,2‐dihalobenzenes as the coupling partners was investigated. The higher reactivity of pyrrole C2−H bond compared to C−H bonds of the aryl unit of 1‐arylpyrroles allows selective synthesis of pyrrolo[1,2‐f]phenanthridines via successive palladium‐catalyzed direct intermolecular followed by intramolecular direct arylation steps. From 1‐bromo‐2‐iodobenzenes bearing substituents at C4‐ or C5‐positions and ortho‐, meta‐ or para‐substituted 1‐arylpyrroles, the access to pyrrolo[1,2‐f]phenanthridines containing substituents at C5, C6, C7, C8, C10 and/or C11 positions is possible.