Enantioselective Synthesis of N−N Biaryl Atropisomers through Iridium(I)-Catalyzed C−H Alkylation with Acrylates

Abstract

Enantioselective synthesis of N−N biaryl atropisomers is an emerging area but remains underexplored. The development of efficient synthesis of N−N biaryl atropisomers is in great demand. Herein, the construction of N−N biaryl atropisomers through iridium-catalyzed asymmetric C−H alkylation is reported for the first time. In the presence of readily available Ir precursor and Xyl-BINAP, a variety of axially chiral molecules based on indole-pyrrole skeleton were obtained in good yields (up to 98 %) with excellent enantioselectivity (up to 99 % ee). In addition, N−N bispyrrole atropisomers could also be synthesized in excellent yields and enantioselectivity. This method features perfect atom economy, wide substrate scope, and multifunctionalized products allowing diverse transformations.