Synthesis, characterization and electrocatalytic H2 production of base-containing Fe/S and Fe/Se clusters

Abstract

Reaction of base-containing diphosphine ligand NPS2 (NP2(Ph2PCH2)2NCH3) with [Fe3(CO)12] in THF at room temperature forms [{Fe2(CO)6(µ-PPh2)}2(µ4-S2)] (1) and [Fe3(CO)8(µ3-S)2{kP-PPh2CH2N(CH3)CH2P(S)Ph2}] (2) resulting from PS bond cleavage and PFe bond formation. Similarly, NPSe2 reacts with Fe3(CO)12 to provide [{Fe2(CO)6(µ-PPh2)}2(µ4-Se2)] (3) and [Fe3(CO)7(µ3-Se)2{k2P,P-(PPh2CH2)2NCH3}] (4). All the compounds have been completely characterized by elemental analyses, IR, 1H NMR, 13C NMR and 31P NMR spectroscopy and structurally determined by X-ray crystallography. Electrochemical studies reveal that when using HOAc or TFA as a proton source, 2 and 4 exhibit catalytic H2 production.