Syntheses, crystal structures, and electrochemical studies of Fe2(CO)6(μ-PPh2)(μ-L) (L = OH, OPPh2, PPh2)

Reaction of Fe-3(CO)(12) and Ph2PH in the presence of Et3N in THF at 0 degrees C immediately forms Fe-2(CO)(6)(mu-PPh2)(mu-OH) (1), Fe-2(CO)(6)(mu-PPh2)(mu-k(2)O,P-OPPh2) (2), and Fe-2(CO)(6)(mu-PPh2)(2) (3) in yields of 25, 14, and 19%, respectively. Experiments confirm that Et3N shortens the reaction time. The absence of O-2 hinders the formation of 2. The presence of H2O can increase the yield of 1. Their structures have been determined by X-ray crystallography and the complexes have been completely characterized by EA, IR, and H-1, C-13, P-31 NMR. Electrochemical studies reveal that they exhibit catalytic H-2-producing activities.