Electrochemically driven hydrophosphination of alkenes and alkynes with diphenylphosphine.

We herein report a mild, efficient, and sustainable electrochemical method for the hydrophosphination of a broad range of alkynes and alkenes with diphenylphosphine. This transition metal-free and additive-free protocol exhibits wide substrate compatibility, delivering the corresponding vinylphosphines and alkylphosphines in good to excellent yields. Moreover, the method is scalable to gram-scale synthesis and enables further transformations in an efficient manner. Mechanistic studies suggest that the reaction proceeds electrochemically induced addition of diphenylphosphinyl radicals to alkynes or alkenes.