Synthesis of N-Substituted Indole Derivatives via PIFA-Mediated Intramolecular Cyclization

A variety of N-arylated and N-alkylated indole derivatives were synthesized by way of a phenyliodine bis(trifluoroacetate) (PIFA)-mediated intramolecular cyclization. This novel method allows for the construction of an indole skeleton by joining the N-atom on the side chain to the benzene ring at the last synthetic step. Other novel pyrrole-fused aromatic compounds can also be achieved by this method.