Spectroscopic and structural studies of 6,6'-bis(N-methylhydrazine)-2,2'-bipyridine and its mononuclear copper(II) complex

The tetradentate ligand, 6,6'-bis(N-methylhydrazine)-2,2'-bipyridine (L) and its mononuclear copper(II) complex [Cu(L)](ClO4)2] (1) have been synthesized and characterized. The crystal structures of L and 1 have been determined by single-crystal X-ray diffraction. Both crystallize in the centrosymmetric monoclinic space group with crystallographic inversion symmetry. The ligand adopts a planar transoid configuration in the solid state. In 1, the Cu(II) is six-coordinate octahedral, defined by N4O2 donors from ligand and two perchlorates. The molecular units are connected by intermolecular H-bonds between the hydrazino group of the one unit and coordinated perchlorate of the neighboring two units via N-H center dot center dot center dot O to furnish a 2-D network. Coordinated perchlorates also form an intramolecular H-bond with hydrazine influencing the crystal packing.