Abstract In this contribution, two diiron ethane-1,2-dithiolate complexes with one ethyldiphenylphosphine or dicyclohexylphenylphosphine ligand have been synthesized and characterized as mimics for the active site of [FeFe]-hydrogenases. Treatment of complex [Fe2(CO)6(μ-SCH2CH2S)] (1) with ethyldiphenylphosphine or dicyclohexylphenylphosphine and Me3NO · 2 H2O as decarbonylating agent gave complexes [Fe2(CO)5(Ph2PCH2CH3)(μ-SCH2CH2S)] (2) and [Fe2(CO)5{PhP(C6H11)2}(μ-SCH2CH2S)] (3) in 93% and 86% yields, respectively. Complexes 2 and 3 were characterized by elemental analysis, IR, and NMR spectroscopy. X-ray crystallographic studies confirmed the molecular structures of complexes 2 and 3, indicating that they contain a butterfly diiron ethane-1,2-dithiolate cluster with five terminal carbonyl ligands and an apically-coordinated phosphine ligand. Additionally, the electrochemical properties of these complexes were investigated by cyclic voltammetry, suggesting that they can be regarded as electrocatalysts for the reduction of protons to H2 in the presence of HOAc. A possible mechanism for the proton reduction was proposed. Graphical Abstract

中文翻译：

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具有单取代乙基二苯基膦或二环己基苯基膦的二铁乙烷-1,2-二硫醇配合物的合成、表征和电化学

摘要 在这项贡献中，合成了两个带有一个乙基二苯基膦或二环己基苯基膦配体的二铁乙烷-1,2-二硫醇配合物，并将其表征为 [FeFe]-氢化酶活性位点的模拟物。用乙基二苯基膦或二环己基苯基膦和Me3NO·2 H2O作为脱羰剂处理配合物[Fe2(CO)6(μ-SCH2CH2S)](1)得到配合物[Fe2(CO)5(Ph2PCH2CH3)(μ-SCH2CH2S)](2)和 [Fe2(CO)5{PhP(C6H11)2}(μ-SCH2CH2S)] (3) 的产率分别为 93% 和 86%。配合物 2 和 3 的特征是元素分析、红外光谱和核磁共振光谱。X 射线晶体学研究证实了配合物 2 和 3 的分子结构，表明它们包含具有五个末端羰基配体和顶部配位膦配体的蝶形二铁乙烷-1,2-二硫醇簇。此外，通过循环伏安法研究了这些配合物的电化学性质，表明它们可以被视为在 HOAc 存在下将质子还原为 H2 的电催化剂。提出了质子还原的可能机制。图形概要