Synthesis, characterization, and electrochemistry of five diiron propane-1,3-dithiolate complexes with substituted phosphine ligands

Abstract

In this paper, five diiron propane-1,3-dithiolate complexes containing substituted phosphine ligands were prepared and structurally characterized. Treatment of [Fe₂(CO)₆(μ-SCH₂CH₂CH₂S)] (1) with a monophosphine ligand methyl diphenylphosphinite, ethyl diphenylphosphinite, 4-(dimethylamino)phenyldiphenylphosphine, tris(2-methoxyphenyl)phosphine, or tris(4-chlorophenyl)phosphine in the presence of Me₃NO·2H₂O as the decarbonylating agent gave the corresponding phosphine-substituted analogues [Fe₂(CO)₅(L)(μ-SCH₂CH₂CH₂S)] [L = Ph₂POCH₃, 2; Ph₂POCH₂CH₃, 3; Ph₂P(4-C₆H₄ NMe₂), 4; P(2-C₆H₄OCH₃)₃, 5; P(4-C₆H₄Cl)₃, 6] in 73–93% yields. Complexes 2–6 have been characterized by elemental analysis, spectroscopy, and X-ray crystallography. Additionally, electrochemical studies have shown that 2–6 can catalyze the reduction of protons to H₂ in the presence of HOAc.

Keywords:

• Diiron propane-1,3-dithiolate
• phosphine ligand
• synthesis
• crystal structure
• electrochemistry

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by Zhejiang Provincial Natural Science Foundation of China under Grant LY19B020002, the Natural Science Foundation of Shanxi Province under Grant 201701D121035, the Scientific Research Foundation for the Returned Overseas Chinese Scholars of Shanxi Province, National Natural Science Foundation of China under Grant 21501124, Science & Technology Department of Sichuan Province under Grant 2018JY0235, and Education Department of Sichuan Province under Grant 18ZA0337.