Tandem Catalytic Indolization/Enantioconvergent Substitution of Alcohols by Borrowing Hydrogen to Access Tricyclic Indoles

• Published in: Angewandte Chemie Vol. 133; no. 38; pp. 20857 - 20862
• Main Authors: Yang, Guoqiang, Pan, Jiaoting, Ke, Ya‐Ming, Liu, Yongbing, Zhao, Yu
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 13-09-2021
• Subjects: Alcohols; Aniline; Catalysis; Chemistry; Direct conversion; enantioselectivity; hydrogen; Indoles; Iridium; Iridium compounds; Phosphoric acid; redox-neutral catalysis; relay catalysis; Stereoselectivity; Substitutes; tricyclic indoles
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202106514

An efficient tandem catalysis method is achieved for the direct conversion of alcohol‐containing alkynyl anilines to valuable chiral 2,3‐fused tricyclic indoles. This method relies on a tandem indolization followed by enantioconvergent substitution of alcohols via borrowing hydrogen to construct two rings in one step, enabled by relay and cooperative catalysis of a chiral iridium complex with a chiral phosphoric acid. Highly diastereoselective transformations of the tricyclic indole products also provide efficient access to a diverse array of complex polycyclic indoline compounds.
An efficient indolization/enantioconvergent borrowing hydrogen cascade is achieved for the construction of chiral 2,3‐fused tricyclic indoles, enabled by relay and cooperative catalysis of a chiral iridium complex with a chiral phosphoric acid. Highly diastereoselective transformations of the tricyclic indole products also provide efficient access to a diverse array of complex polycyclic indolines.