Synthesis, characterization and electrochemistry of diiron 1,2-dithiolate complexes with a trans-cinnamate ester

Abstract

Three diiron 1,2-dithiolate complexes with a trans-cinnamate ester have been characterized. Esterification of [Fe₂(CO)₆{μ-SCH₂CH(CH₂OH)S}] (1) with trans-cinnamic acid in the presence of N,N′-dicyclohexylcarbodiimide and 4-dimethylaminopyridine afforded [Fe₂(CO)₆[μ-SCH₂CH(CH₂O₂CCH = CHPh)S}] (2) in 94% yield. Carbonyl substitution of 2 with a monophosphine ligand tris(4-fluorophenyl)phosphine or tris(2-methoxyphenyl)phosphine in the presence of Me₃NO·2H₂O resulted in formation of the corresponding monophosphine-substituted complexes [Fe₂(CO)₅ {P(C₆H₄F-4)₃}{µ-SCH₂CH(CH₂O₂CCH = CHPh)S}] (3) and [Fe₂(CO)₅{P (C₆H₄OCH₃-2)₃}{µ-SCH₂CH(CH₂O₂CCH = CHPh)S}] (4) in 79% and 84% yields, respectively. Complexes 2-4 were structurally characterized by elemental analysis, spectroscopy and X-ray crystallography. Moreover, electrochemical properties of 2-4 were investigated.

Keywords:

• Diiron 1,2-dithiolate
• trans-cinnamic acid
• esterification
• carbonyl substitution
• electrochemistry

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors gratefully acknowledge the support of the National Natural Science Foundation of China (No. 21501124), the Natural Science Foundation of Zhejiang Province (No. LY19B020002), Science & Technology Department of Sichuan Province (No. 2018JY0235), Education Department of Sichuan Province (No. 18ZA0337), the Sichuan University of Science & Engineering (No. 2014RC05, 201710622016) and Ningbo Natural Science Foundation (No. 2015A610278).