N-Heterocyclic Carbene-Catalyzed Desymmetrization of Bishydroxymethylphosphines to Access P‑Stereogenic Compounds

P-stereogenic compounds are widely found in natural products, pharmaceuticals, and chiral ligands. However, their efficient asymmetric synthesis remains challenging. Herein, we report an N-heterocyclic carbene-catalyzed desymmetrization of prochiral bishydroxymethylphosphine sulfides, affording a series of P-chiral compounds in moderate to good yields with high enantioselectivities. This protocol features mild conditions, good functional group tolerance, and scalability to the gram scale. Moreover, the products can be readily transformed into P-stereogenic triarylphosphines with potential as chiral ligands in asymmetric catalysis. Density functional theory calculations were performed to elucidate the origin of the enantioselectivity and to probe the possible involvement of a noncovalent P···Br pnictogen bond interaction.