POLYNUCLEAR COMPLEXES OF COPPER(II) - SYNTHESIS, CHARACTERIZATION, CRYSTAL AND MOLECULAR-STRUCTURE OF THE CATIONS BIS[OXAMIDATE-N,N'-DIPROPYLAMINE-2,2'-DIMETHYL-N,N',N1,N1'-COPPER(II)]COPPER(II) ([CUN4CUO4CUN4]2+) AND BIS[OXAMIDATE-N,N'-DIPROPYLAMINE-2,2'-DIMETHYL-N,N',N1,N1'-COPPER(II)]DICOPPER(II)-O,O1,O2,N1,N2-MU-(OXAMIDATE-N,N'-DIPROPYLAMINE-2,2'-DIMETHYL-N,N',O,N1,N1',O1) ([CUN4(CUN2O3)2CUN4]2+) PACKED IN THE SAME CRYSTAL AS THEIR TETRANITRATE DIHYDRATE SALTS

The product of the reaction between copper(II) nitrate and oxamidate-N,N'-dipropylamine-2-2'-dimethyl-N,N',N1,N1'-copper(II) was isolated and characterized by crystallographic and spectroscopic measurements. The title compound crystallizes in the triclinic space group P1BAR with cell dimensions a = 12.426(1), b = 13.405(1), c = 15.605(2) angstrom, alpha = 102.35(1), beta = 105.34(1), gamma = 113.74(1)-degrees, Z = 1. The crystal consists of tricopper and tetracopper dications packed together in a 1:1 ratio and placed around inversion centres. The tricopper cation contains a central CuO4 and two outer CuN4 square units; the copper in the CuN4 units exhibits a fifth interaction with a nitrate oxygen. The tetracopper cation contains two inner square pyramidal CuN2O3 units and two outer CuN4 square units weakly bound to a fifth nitrate oxygen. The oxamidate ligands exhibit two different conformations and act as hexadentate ligands, with four N donor atoms and two O donor atoms.