Synthesis and crystal structure of a novel binuclear Cu(II) complex with tetradentate Schiff-base ligand

A novel binuclear complex ([Cu-2(mu(2)-shed)(hshed)]center dot(ClO4)center dot H2O, h(2)shed = N-salicyliden-N'-(2-hydroxyethyl)ethylenediamine) has been synthesized and structurally characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P2(1)/c with a = 12.511(10), b = 15.750(12), c = 14.281(12) angstrom, beta = 100.564(14)degrees, C22H31ClN4O9Cu2, M-r = 658.04, V = 2766(4) angstrom(3), Z = 4, D-c = 1.580 g/cm(3), mu(MoK alpha) = 1.689 mm(-1), F(000) = 1352, the final R = 0.0528 and wR = 0.1433 for 4880 independent reflections with R-int = 0.0577. The complex is a binuclear copper compound, and two Cu(II) ions in the binuclear cation are in different coordination environments. The Cu(I) ion adopts a distorted square pyramidal geometry (tau = 0.22) with four donor atoms (N2O2) of the ligand in the basal plane, and one hydroxyl oxygen atom with protonated form occupying the apical position. The Cu(2) ion assumes the geometry of a distorted square plane with four donor atoms (N2O2) of the ligand. The Cu center dot center dot center dot Cu separation is 3.103 angstrom. In addition, N-H center dot center dot center dot O and C-H center dot center dot center dot O intermolecular hydrogen bonding interactions link these binuclear cations into a quasi one-dimensional chain along the a axis.