Phosphine-substituted diiron 1,2-dithiolate complexes as the models for the active site of [FeFe]-hydrogenases

Abstract

In this article, five diiron 1,2-dithiolate complexes containing phosphine ligands are reported. Treatment of complex [Fe₂(CO)₆(μ-SCH₂CH₂S)] (1) with the phosphine ligands tris(4-methylphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(3-chlorophenyl)phosphine, tris(3-methylphenyl)phosphine, or 2-(diphenylphosphino)biphenyl in the presence of Me₃NO·2H₂O as the decarbonylating agent afforded the target products [Fe₂(CO)₅(L)(μ-SCH₂CH₂S)] [L = P(4-C₆H₄CH₃)₃, 2; P(4-C₆H₄OCH₃)₃, 3; P(3-C₆H₄Cl)₃, 4; P(3-C₆H₄CH₃)₃, 5; Ph₂P(2-C₆H₄Ph), 6] in 80–93% yields. Complexes 2–6 have been characterized by elemental analysis, spectroscopy, and X-ray crystallography. Additionally, the electrochemical properties were studied by cyclic voltammetry.

Graphical Abstract

Keywords:

• Diiron 1,2-dithiolate
• [FeFe]-Hydrogenases
• monophosphine
• X-ray crystallography
• electrochemistry

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors gratefully acknowledge the support of the Zhejiang Provincial Natural Science Foundation of China (No. LY19B020002), the National Natural Science Foundation of China (No. 21501124), Science & Technology Department of Sichuan Province (No. 2018JY0235), and Education Department of Sichuan Province (No. 18ZA0337).