Synthesis of vinylphosphines and unsymmetric diphosphines: iron-catalyzed selective hydrophosphination reaction of alkynes and vinylphosphines with secondary phosphines.

Iron complex-catalyzed regioselective single hydrophosphination of terminal arylalkynes with secondary phosphines was achieved. Unsymmetric 1,2-bis(phosphino)ethanes with different phosphino groups were obtained by using our catalytic systems. The structures of the obtained vinylphosphine, unsymmetric 1,2-bis(phosphino)ethane, and iron catalyst precursors were confirmed by single crystal X-ray diffraction studies.