Crystal structure of Na₂[{Cu₂(O₂CH)₄}{Cu(O₂CH)₄}]

Abstract

The cyanamido-nitrate ligand has potentially four donor atoms: N(amide), N(nitrile) and two O atoms.The variety of coordination opportunities for cyanamidonitrate ligand (monodentate, or bidentate bridging ligand), in dependence on the kind of the central atom, especially on its hardness is expected.New cyanamidonitrate complex of composition [Cu(NO2NCN)2(dmpz)3] (where (dmpz) = 3,5-dimethylpyrazole) was prepared and the crystal structure solved.The crystal structure is built from discrete [Cu(NO2NCN)2(dmpz)3] units.The central Cu(II) atom is found to be in the tetragonal-pyramid coordination.In equatorial plane there are three 3,5dimethylpyrazole molecules and one cyanamidonitrate anion coordinated by nitrile nitrogen atom.The axial position is completed by nitrile nitrogen atom from another cyanamidonitrate anion.Interatomic distances are compared and discussed with others solved crystal structures: [Cu(NO2NCN)2(1-meiz)4] [1], [Cu(NO2NCN)2(5-meiz)4] [1], [Cu(NO2NCN)2(iz)2] [2], [Ni(NO2NCN)2(1meiz)4] [3], [Ni(NO2NCN)2(pz)4] [4] and [Co(NO2NCN)2(iz)4] [3] (where meiz = methylimidazole, iz = imidazole, pz = pyrazole).