| Abstract |
Upon reaction of 2-(2-(4,4-dimethyl-2,6-dioxocyclohexylidene)hydrazinyl)benzoic acid (H2L, 1) with Cu(NO3)(2)center dot 2.5H(2)O and imidazole (im) or ethylenediamine (en), the mononuclear ([Cu(H2O)(2)(ed)(2)](2+)(HL-)(2)\center dot 6H(2)O (2) and binuclear [Cu(1 kappa N,O-2:2 kappa O-L)(im)](2) (3) complexes, respectively, were obtained. A trinuclear mixed-valence cobalt(II,III) complex, [\Co(1 kappa N,O-2-L)(1 kappa N,O-2:2 kappa O-mu-L)\Co-0.5(H2O)(2)](2)center dot 10H(2)O, (4.10H(2)0) is formed when Co(NO3)(2)center dot 6H(2)O reacts with H2L in methanol. Compounds 1-4 were fully characterized by IR spectroscopy, ESI-MS, elemental and single-crystal X-ray diffraction analyses. The crystal structure of 2 consists of two anionic HL- moieties along with the distorted octahedral [Cu(H2O)(2)(en)(2)](2+) complex cation. The Cu(II) centers in 3 display distorted square pyramid coordination modes (tau 5 = 0.2) with a Cu center dot center dot center dot Cu distance within the Cu2O2 core of 3.2490(18) angstrom. In 4 the cobalt centers display octahedral geometries. The structural units in 3 and 4 are combined into infinite 1D chains along the crystallographic b and a axis, respectively, by means of intermolecular H contacts. In 4 the structure further extends into the second dimension by means of extensive H-bonding interactions involving water molecules. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved. |
