A Dinuclear Copper(II) Complex Based On the Bisoxime Ligand 5,5′-Dimethoxy-2,2′-[(ethylene)dioxybis(nitrilomethylidyne)]diphenol: Synthesis, Crystal Structure and Spectral Properties

A dinuclear Cu(II) complex, [Cu-2(L-2)(2)] (H2L2 = 4-methoxysalicylaldehyde O-(2-hydroxyethyl)oxime), has been synthesized through the complexation of Cu(II) acetate monohydrate with the ligand H2L1 (H2L1 = 5,5'-dimethoxy-2,2'-[(ethylene)dioxybis(nitrilomethylidyne)]diphenol), and characterized by elemental analyses, IR, UV/Vis and emission spectra. The crystal structure of the Cu(II) complex has been determined by single-crystal X-ray diffraction. The catalysis by Cu(II) ions results in the unexpected cleavage of the N-O bonds in the ligand H2L1, giving a novel dialkoxo-bridged dinuclear Cu(II) complex possessing a Cu-O-Cu-O four-membered ring core instead of the expected salen-type bisoxime Cu-N2O2 complex.