Ni(II) and Cu(II) complexes with the dianionic N,N,O-tridentate Schiff base 6-amino-5-formyl-1,3-dimethyluracil-benzoylhydrazone
作者:Francisco Hueso-Ureña、Nuria A. Illán-Cabeza、Miguel N. Moreno-Carretero、Antonio L. Peñas-Chamorro、René Faure
DOI:10.1016/s0277-5387(00)00309-0
日期:2000.3
From the reaction between Cu(II) and Ni(II) salts and the Schiff base 6-amino-5-formyl-1,3-dimethyluracil-benzo (H(2)BEZDO), in dimethylformamide (DMF)-water and ammonia media, the complexes Ni(BEZDO) . H2O . NH3, Cu(BEZDO) . H2O . NH3 and [Cu(BEZDO)(H2O)] . H2O containing the dianionic organic ligand have been obtained. These compounds have been studied by IR, electronic and EPR spectroscopy and magnetic measurements. The structure of [Cu(BEZDO) (H2O)] . H2O has been solved by means of X-ray diffraction methods. The coordination environment around the Cu(II) may be described as a square-plane structure in which the Schiff base acts as tridentate ligand through the N(6), N(51) and O(52) atoms, making two five- and six-membered chelate rings. The coordination sphere is completed with the oxygen atom of a water molecule; any additional interactions with potential donor atoms in the axial direction have not been found. The crystal structure is formed by infinite hydrogen-bonded monodimensional chains, in which the nearest metal centres are at distances of 4.511 and 3.585 Angstrom. (C) 2000 Elsevier Science Ltd All rights reserved.