An unusual oxo-bridged rhenium complex with the Re centers in different coordination environments

The reaction of the complex [ReOBr3(PPh3)2] with 3,5-dimethylpyrazole (3,5-Me2pzH) in acidified acetone at room temperature has been examined and a novel dinuclear oxocompound, [{ReOBr4}(μ-O){ReO(3,5-Me2pzH)4}], has been obtained. It has been studied by IR, UV–Vis spectroscopy, magnetization measurements and X-ray crystallography. The electronic structure of [{ReOBr4}(μ-O){ReO(3,5-Me2pzH)4}] has been calculated with the density functional theory (DFT) method. The spin-allowed singlet–singlet electronic transitions of [{ReOBr4}(μ-O){ReO(3,5-Me2pzH)4}] have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of the title compound has been discussed on this basis.

Graphical abstractThe reaction of the complex [ReOBr3(PPh3)2] with 3,5-dimethylpyrazole (3,5-Me2pzH) in acidified acetone at room temperature has been examined and a novel dinuclear oxocompound, [{ReOBr4}(μ-O){ReO(3,5-Me2pzH)4}], has been obtained. It has been studied by IR, UV–Vis spectroscopy, magnetization measurements and X-ray crystallography. The electronic structure of [{ReOBr4}(μ-O){ReO(3,5-Me2pzH)4}] has been calculated with the density functional theory (DFT) method. The spin-allowed singlet–singlet electronic transitions of [{ReOBr4}(μ-O){ReO(3,5-Me2pzH)4}] have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of the title compound has been discussed on this basis.Figure optionsDownload full-size imageDownload as PowerPoint slide