Accessing Axially and Centrally Chiral <i>N</i> -Arylindoles Merging n → π* Interaction with Organocatalyzed Pictet–Spengler-Type Cyclization

Abstract

Herein, we present a chiral phosphoric acid-catalyzed dynamic kinetic resolution strategy that achieves precise control over both axial and point chiralities in N -arylindoles by merging the N(sp 3 )···C═O n → π* interaction with the Pictet–Spengler-type cyclization. A series of centrally chiral dihydropyrrolo[1,2- a ]quinoxaline-fused N -arylindole atropisomers were obtained with high to excellent results (up to 99% yield, >20:1 dr and 98% ee). The methodology exhibits scalability, mild conditions, and good functional group tolerance, making it a promising option for research into multiple chiral N -containing polycyclic frameworks.

Topics & Concepts