Synthesis, crystal structure and physicochemical properties of copper(II) complexes containing bis[(benzimidazol-2-yl)methyl] ether derivatives

A new benzimidazoyl ligand bis[(N-ethylbenzimidazol-2-yl)methyl]ether (EDGB) and Cu-II complexes [Cu(L-1) (L-2)](ClO4). mEt(2)O . nH(2)O [L-1 = bis[(benzimidazol-2-yl)methyl]ether (DGB) or EDGB, L-2 = 2,2'-bipyridine (bipy) or 1,10-phenanthroline (phen)] have been synthesized and characterized by elemental analyses and i.r. spectra. The single-crystal structure of the [Cu(phen)(DGB)(OClO3)]ClO4. Et2O . 0.5H(2)O complex was determined by X-ray diffraction. The geometry around Cu is best described as a distorted octahedron with four nitrogen atoms from phen and DGB ligands forming the equatorial plane. The oxygen atoms of DGB and one perchlorate group are in the axial positions with semi-coordinated bonding modes. The electrochemical behavior of the complexes is described.