Copper-CatalyzedDynamic Kinetic Asymmetric Arylationof Secondary Phosphine-Boranes for the Synthesis of P(III)-StereogenicCenters

Transition-metal-catalyzed asymmetric C–P(III) bond formation is a direct method for the construction of P(III)-stereogenic centers; however, achieving high enantioselectivity remains a challenge. Herein, an unprecedented Cu-catalyzed dynamic kinetic resolution of secondary phosphine-boranes was successfully developed. This asymmetric C–P(BH₃) coupling reaction provided the direct and highly enantioselective synthesis of P(III)-stereogenic centers, enabling the formation of chiral medium-sized benzophosphine-boranes (7–10-membered cycles). A mechanism of dynamic kinetic resolution involving the unusual rapid racemization of secondary phosphine-boranes has been proposed.