9-BBN and chloride catalyzed reduction of chlorophosphines to phosphines and diphosphines

The commercially available Lewis acid, 9-BBN and Lewis basic [Et4N]Cl are used as catalysts for the reduction of chlorophosphines R2PCl in the presence of phenylsilane. Aryl-chlorophosphines afford primarily diphosphines (P2R4) while secondary phosphines predominate for alkyl-substituted precursors. Use of the combined catalysts leads to reduced reaction time and temperature, providing a rapid, scalable, and facile protocol for the preparation of diphosphines or secondary phosphines.