Crystal structure and electrocatalytic investigation of diiron azadiphosphine complex [Fe2(μ-pdt)(CO)4{(μ-Ph2P)2NH}] related to [FeFe]-hydrogenases

The solid-state structure of diiron azadiphosphine complex [Fe2(μ-pdt)(CO)4{(μ-Ph2P)2NH}] (1) bearing a pendant amine, which can be regarded as the diiron subsite model of [FeFe]-hydrogenases, have been well investigated by X-ray crystallography. Notably, in order to explore the potential role of a pendant amine in the bridging azadiphosphine ligand, the electrochemical and electrocatalytic properties of 1 and its reference analog [Fe2(μ-pdt)(CO)4{(μ-Ph2P)2CH2}] (2) have been studied and compared in the absence and presence of acetic acid (HOAc) as a proton source using cyclic voltammetry (CV), indicating that they are active for the electrocatalytic proton reduction to hydrogen (H2).