Mononuclear and binuclear copper(II) complexes with bis(2-imidazolyl)(bis(methoxycarbonyl)methylmethane) (BIBM), a tripodal bis(imidazole) based ligand. Synthesis, crystal structure and magnetic Characterization of [Cu(BIBM)2](ClO4)2 and [{Cu(BIBM)(H2O)}2(μ1,2,3,4-C2O4)](C4O4)·6H2O

Two new Cu(II) complexes with bis(2-imidazolyl) (bis(methoxycarbonyl)methylmethane) (BIBM), a tridentate bis(imidazole) based ligand with the formula [Cu(BIBM) 2 ](ClO 4 ) 2 ( 1 ) and [{Cu(BIBM)(H 2 O)} 2 (μ 1,2,3,4 -C 2 O 4 )](C 4 O 4 )·6H 2 O ( 2 ) have been synthesized and characterized. Compound 1 shows mononuclear cationic [Cu(BIBM) 2 ] 2+ units and perchlorate ions. The coordination around the Cu(II) ion shows a tetragonally-elongated octahedral geometry. The BIBM ligand acts as a k 3 -N,N’,O tripodal ligand, through two imidazole N atoms and a weak Cu–O(carboxymethyl) axial interaction. In the crystal structure cations and anions connect through H-bonds generating linear chains. Line…