Synthesis and structural characterization of the novel unusual oxido-bridged rhenium complex with Re atoms in two different coordination environments

A new binuclear mixed-valence complex [ReCl4(py)(μ-O)Re(py)4Cl]·2py was obtained by solvothermal synthesis in a Berghoff autoclave. It has been studied by IR, reflectance spectra, TGA and X-ray measurements, which support the assumption, that two Re centres with different coordination environments are present. Most plausible, yet not unambiguous oxidation state assignment is ReIII/IV.