Novel rhenium oxocomplexes of 2-hydroxymethylbenzimidazole - Synthesis, X-ray studies, spectroscopic characterization and DFT calculations

Three novel rhenium oxocomplexes of biologically relevant ligand 2-hydroxymethylbenzimidazole: cis-[ReOCl2(hmbzim)(PPh3)] (1), cis-[ReOBr2(hmbzim)(PPh3)] and [ReO(hmbzim)2(PPh3)](ReO4)·CH3OH (3) have been synthesized and characterized spectroscopically and structurally (by single-crystal X-ray diffraction). The electronic spectra of 1 and 3 were investigated at the TDDFT level employing B3LYP functional in combination with LANL2DZ. Additional information about binding in the complexes 1 and 3 was obtained by NBO analysis.