Ruthenium complexes of 4,4′-bi-1,2,3-thiadiazole and azoimine ligands: syntheses, crystallography, and electrochemical studies

Five ruthenium complexes of the general type trans -[Ru II (btd)(Azo)Cl 2 ] ({Azo = PhN=NC(COMe) = NC 6 HY, where Y = H (a), Me (b), OMe (c), Cl (d) or Br (e)} and btd = 4,4′-bi-1,2,3-thiadiazole) have been prepared by the reaction of RuCl 3 with the ligands in the presence of LiCl. These complexes have been characterized by spectroscopic (IR, UV–Vis, and NMR) and electrochemical techniques. In addition, the complex trans -[Ru II (btd)(L5 ) Cl 2 ] (complex 5) has been characterized by X-ray diffraction analysis. The electrochemical parameter for the π-excessive ligand (btd) is reported. The absorption spectrum of complex 5 in acetonitrile has been modeled by time-dependent density functional theory. Graphical Abstract .