Enantio- and Regioselective Ni-Catalyzed Hydroarylation of Alkenes and Alkynes to Form C–N Axially Chiral Heterobiaryls

Abstract C–N axially chiral heterobiaryls are highly valuable yet synthetically challenging scaffolds. Atroposelective hydroarylation represents an ideal strategy for their construction, offering both high step- and atom-economy. Herein, we report an enantio- and regioselective Ni-catalyzed hydroarylation of unactivated alkenes for the efficient synthesis of C–N axially chiral heterobiaryls. The sterically demanding chiral N-heterocyclic carbene (NHC) ligands enable excellent control over regioselectivity and enantioselectivity, affording a broad range of axially chiral products in good to excellent yields with up to 98% ee. The reaction exhibits broad substrate scope and high functional-group tolerance. Furthermore, the catalytic strategy could be extended to the atroposelective hydroarylation of alkynes, providing direct access to axially chiral alkenyl heterobiaryls with excellent chemo-, regio-, enantio- and E/Z-selectivity. Notably, the use of MeONa proved crucial for precise control of alkene geometry. This study provides a robust platform to advance the development of atroposelective hydroarylation reactions, enabling the construction of a series of novel C–N axially chiral scaffolds.