Palladium-Catalyzed Oxidative Cyclization of Tertiary Enamines for Synthesis of 1,3,4-Trisubstituted Pyrroles and 1,3-Disubstituted Indoles

A novel and efficient palladium-catalyzed intramolecular oxidative cyclization of tertiary enamines for the synthesis of 1,3,4-trisubstituted pyrroles and 1,3-disubstituted indoles has been developed. Trifluoroacetic acid plays an important role in the reaction. A series of pyrroles and indoles with substitution patterns that are not easily accessible by traditional routes were synthesized in good yields under mild conditions.