Preparation, crystal structures and spectroscopic characterization of oxalate copper(II) complexes containing the nitrogen ligands 4,4′-dimethyl-2,2′-bipyridine and di(2-pyridyl)sulfide

The preparation, crystal structures and spectroscopic characterization of four oxalate copper(II) complexes containing the 4,4′-dimethyl-2,2′-bipyridine (Mebpy) or di(2-pyridyl)sulfide (DPS) nitrogen ligands namely [μ-(ox){Cu(Mebpy)(NO3)(H2O)}2] (1), [μ-(ox){Cu(Mebpy)(ClO4)(H2O)}2] (2), [μ-(ox){Cu(DPS)(H2O)}2](ClO4)2 (3) and [Cu(DPS)(ox)(H2O)] · 2H2O (4) are described. X-ray diffraction measurements have shown that complexes 1–3 are binuclear, in which the oxalate anion bridges two Cu(II) centers, while the complex (4) is mononuclear and the oxalate anion adopts the terminal bidentate chelating coordination mode. In 1 and 2 the Cu(II) sites display a distorted octahedral geometry (4+2 environment) and in compounds 3 and 4 the Cu(II) centers exhibit a slightly distorted square pyramidal geometry. In addition, complexes 1 and 2 present a 2D supramolecular arrangement through hydrogen bonds between coordination water molecules and nitrate or perchlorate anions and π-stacking interaction between the pyridyl rings of Mebpy nitrogen ligands.

The preparation, crystal structures and spectroscopic characterization of four oxalate copper(II) complexes containing the 4,4′-dimethyl-2,2′-bipyridine (Mebpy) or di(2-pyridyl)sulfide (DPS) nitrogen ligands namely [μ-(ox){Cu(Mebpy)(NO3)(H2O)}2] (1), [μ-(ox){Cu(Mebpy)(ClO4)(H2O)}2] (2), [μ-(ox){Cu(DPS)(H2O)}2](ClO4)2 (3) and [Cu(DPS)(ox)(H2O)] · 2H2O (4) are described. The complexes 1–3 are binuclear while the complex (4) is mononuclear and all of them can be used as molecular building blocks for coordination polymers construction.Figure optionsDownload as PowerPoint slide