Br?nsted Acid Catalyzed Cascade Reactions of 2?[(2?Aminophenyl)ethynyl]phenylamine Derivatives with Aldehydes: A New Approach to the Synthesis of 2,2′-Disubstituted 1H,1′H?3,3′?Biindoles

摘要

An unusual Br?nsted acid catalyzed cascade reaction of 2-[(2- aminophenyl)ethynyl]phenylamine derivatives with aryl(heteroaryl)aldehydes to afford an efficient alternative entry into 2,2′-disubstituted-1H,1′H-3,3′-biindoles under metal-free conditions is reported.