A Strategy for Synthesizing Axially Chiral Naphthyl‐Indoles: Catalytic Asymmetric Addition Reactions of Racemic Substrates

• Published in: Angewandte Chemie International Edition Vol. 58; no. 42; pp. 15104 - 15110
• Main Authors: Jiang, Fei, Chen, Ke‐Wei, Wu, Ping, Zhang, Yu‐Chen, Jiao, Yinchun, Shi, Feng
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 14-10-2019
• Edition: International ed. in English
• Subjects: Alcohols; asymmetric catalysis; Asymmetry; atropisomer-selectivity; axial chirality; Catalysis; Chemical synthesis; Enantiomers; enantioselectivity; Indoles; o-hydroxybenzyl alcohols; Phosphoric acid; Substrates; axial chirality; enantioselectivity; asymmetric catalysis; o-hydroxybenzyl alcohols; atropisomer-selectivity
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201908279

A new strategy for enantioselective synthesis of axially chiral naphthyl‐indoles has been established through catalytic asymmetric addition reactions of racemic naphthyl‐indoles with bulky electrophiles. Under chiral phosphoric acid catalysis, azodicarboxylates and o‐hydroxybenzyl alcohols served as bulky but reactive electrophiles that were attacked by C2‐unsubstituted naphthyl‐indoles, which underwent a dynamic kinetic resolution to afford two series of axially chiral naphthyl‐indoles in good yields (up to 98 %) and high enantioselectivities (up to 98:2 er).
A new strategy for enantioselective synthesis of axially chiral naphthyl‐indoles was established by catalytic asymmetric addition reactions of racemic naphthyl‐indoles with bulky electrophiles. Under chiral Brønsted acid (B*−H) catalysis, azodicarboxylates and o‐hydroxybenzyl alcohols served as bulky but reactive electrophiles that were attacked by C2‐unsubstituted naphthyl‐indoles, affording axially chiral naphthyl‐indoles in good yields and enantioselectivities.