Access to N-unprotected 2-amide-substituted indoles from Ugi adducts via palladium-catalyzed intramolecular cyclization of o-iodoanilines bearing furan rings

作者：Peng, Hui; Jiang, Kai; Zhen, Guangjin; Wang, Furong^*; Yin, Biaolin^*

来源：2020, 10(20): 11750-11754.

DOI：10.1039/d0ra01830a

• DIVERSITY-ORIENTED SYNTHESIS
• CASCADE REACTIONS
• ALPHA-ARYLATION
• STRATEGY
• CONSTRUCTION
• HETEROCYCLES
• PROGRESS
• ALLENES
• MILD

A variety of N-unprotected 2-amide-substituted indoles were synthesized from readily available furfural-based Ugi adducts in moderate to good yields via palladium-catalyzed intramolecular cyclization of o-iodoanilines bearing furan rings. These reactions involved a cascade sequence consisting of dearomatizing arylation, opening of the furan ring, and deprotection of the N atom.