Diiron ethanedithiolate complexes with pendant ferrocene: Synthesis, characterization and electrochemistry

Three diiron ethanedithiolate complexes containing pendant ferrocene were prepared and structurally characterized. Reaction of the complex [{mu-SCH2CH(CH2OH)S}Fe-2(CO)(6)] (1) with ferrocenecarboxylic acid in the presence of N,N'-dicyclohexylcarbodiimide and 4-dimethylaminopyridine afforded complex [{mu-SCH2CH(CH(2)O(2)CFc)S}Fe-2(CO)(6)] (Fc = ferrocenyl) (2) in 73% yield. Further treatment of complex 2 with a monophosphine ligand tris(2-methoxyphenyl)phosphine or tris(2-furyl)phosphine in the presence of the decarbonylating agent Me3NO center dot 2H(2)O yielded the monophosphine-substituted complexes [{mu-SCH2CH(CH(2)O(2)CFc)S}Fe-2(CO)(5)P(2-C6H4OCH3)(3)] (3) and [{mu-SCH2CH(CH(2)O(2)CFc)S}Fe-2(CO)(5)P(2-C4H3O)(3)] (4) in 94% and 85% yields, respectively. The complexes 2-4 were characterized by elemental analysis, spectroscopy and X-ray crystallography. In addition, electrochemical properties of the complexes 2-4 were studied by cyclic voltammetry. (C) 2018 Elsevier Ltd. All rights reserved.