MIXED-LIGAND COPPER(II) COMPLEXES WITH N-METHYL DERIVATIVES OF IMINODIACETATO OR IMIDAZOLE - CRYSTAL-STRUCTURES OF (N-METHYL-IMINODIACETATO)(IMIDAZOLE) COPPER(II), [CU(MIDA)(IMH)] AND AQUA(IMINODIACETATO)(N-METHYL-IMIDAZOLE)COPPER(II) MONOHYDRATE, [CU(IDA)(1MEIMH)(H2O)(2)]CENTER-DOT-H2O

Equimolar (1:1:1) mixed-ligand Cu(II) complexes with iminodiacetato (I DA) or N-methyl-IDA (MIDA) and N-methyl-imidazole (1MeImH) or ImH, res pectively, have been prepared and characterized by thermal, spectral, magnetic and X-ray diffraction methods. [Cu(MIDA) (ImH)] (I) crystalli zes in the monoclinic system P2(1)/n (a = 12.465(3), b = 5.999(1), c = 14.733(3) Angstrom, beta = 111.91(1)degrees, Z=4, R = 0.043, R(w)= 0. 047). The Cu(II) atom exhibits a flattened square base pyramidal coord ination (type 4 + 1). The N and two O atoms of the tridentate MIDA and one N of ImH form the square base; one longer Cu-O bond with the next MIDA ligand in the chain complex completes the Cu(II) five-coordinati on. [Cu(IDA)(1MeImH)(H2O)(2)]. H2O (II) crystallizes in the orthorhomb ic system Pna2(1) (a = 14.733(2), b = 7.721(1), c = 11.288(1) Angstrom , Z=4, R = 0.041, R(w) = 0.043). The N and two O atoms from IDA and on e N from 1MeImH define a square coordination; two longer Cu-OH, bonds complete the unsymmetrical elongated octahedral coordination of Cu(II) (type 4 + 1 + 1). The polar N-H bonds of ImH in I and of IDA in II as well as the O-H bonds of the water molecules of the latter compound a re involved in hydrogen bonds. The stepwise water loss in II is explai ned on the basis of its structural role in the Cu(II) coordination and /or in the crystal packing.