Synthesis and characterization of mono- and bi-iron chalcogeno-ferrocenylcarboxylato complexes

Abstract

Chalcogenocarboxylato complexes of iron bearing ferrocenyl moieties having two iron atoms in different electronic environments have been synthesized and characterized. Synthesis is accomplished by reactions of (μ-Ex)[CpFe(CO)2]2 (E = S, x = 2–4; E = Se, x = 1) with ferrocenoyl chloride (ClCOC5H4)FeCp which generated CpFe(CO)2ECOC5H4FeCp (E = S (1), Se (2)) in good isolated yields. The analogous reaction with bi-functional ferrocene dicarbonyl dichloride (ClCOC5H4)2Fe gave both the mono substituted products CpFe(CO)2ECOC5H4Fe(C5H4COOH) (E = S (3), Se (4)) or the di-substituted species [CpFe(CO)2ECOC5H4]2Fe (E = S (5), Se (6)). The authentication details of complexes 1–6 are presented along with the results from infrared, ultraviolet-visible, proton and carbon-13 nuclear magnetic resonance spectroscopies. In addition, the structures of 2, 3 and 4 were determined by single crystal X-ray diffraction, evidencing both the half-sandwich and sandwich geometries of the two iron centers.