Enantioselective Cobalt-Catalyzed Reductive Cross-Coupling for the Synthesis of Axially Chiral Phosphine–Olefin Ligands

Transition-metal-catalyzed enantioselective cross-electrophile coupling reactions to construct C­(sp2)–C­(sp2) bonds remain a challenge. Herein, we report a general process for the enantioselective Co-catalyzed reductive cross-coupling reaction of o-(bromo)­arylphosphine oxide substrates and vinyl triflates, delivering axially chiral phosphine oxide compounds with good chemo- and enantioselectivity. A broad range of axially chiral compounds was obtained with excellent enantioselectivities, and the practical potential of this catalyst system was demonstrated by the versatile formation of axially chiral ligands and other functional atropisomers.