Rhodium‐Catalyzed Asymmetric Access to P‐Chiral Triarylphosphine Oxides via Insertion of P−H Bonds into Carbenes

While significant progress has been made in enantioselective insertion of carbenes into heteroatom-hydrogen bonds, this chemistry is predominantly restricted to construction of carbon-based chirality. The asymmetric insertion of carbenes into P-H that delivers P-chiral products remains untouched. We herein report rhodium(I)-catalyzed enantioselective synthesis of P-chiral triarylphosphine oxides via asymmetric C-P coupling of a secondary phosphine oxide (SPO) with diazonaphthoquinone. Driven by aromatization, this protocol affords a variety of P-chiral triarylphosphine oxides tethered to a 2-naphthol functionality in excellent enantioselectivity by following a kinetic resolution reaction pattern. The diverse synthetic and catalytic applications of the P-chiral products highlight the value of this method, even though the derivatized trivalent chiral phosphine bears a rather low barrier of racemization.