Nickel-Catalyzed Enantioselective\nAlkylation of Primary\nPhosphines

Functional molecules derived from stereogenic phosphorus\ncenters\nhave important applications in the discovery of drugs and agrochemicals.\nThey are also widely utilized as chiral ligands or organocatalysts\nfor diverse asymmetric transformations. However, access to P-stereogenic\nmotifs has always been regarded as a highly challenging yet desirable\ngoal in organic synthesis. The development of general and practical\nmethods for the stereoselective construction of synthetically versatile\nP(III)-stereogenic phosphines is particularly appealing but remains\nelusive. Herein, we describe a nickel-catalyzed asymmetric alkylation\nof primary phosphines with alkyl halides for the synthesis of P-stereogenic\nsecondary phosphine-boranes with high enantioselectivity and broad\nsubstrate scope. The resulting optically active secondary phosphine-boranes\nallow for further stereospecific transformations, thereby establishing\na modular and efficient platform for the diversity-oriented construction\nof P-stereogenic phosphine compounds.