A New Class of Heterobinuclear Complexes:Crystal Structure and Magnetism of Copper(II)-Nickel(II) Complexes Incorporating Two Different Macrocyclic Ligands

摘要

Three novel oxamido-bridged heterobinuclear copper(II)-nickel(II) complexes incorporating two different tetraazamacrocyclic compounds were synthesized and characterized by IR,ESR,and electronic spectra.They [(CuL~3)Ni(rac-cth)](ClO)_(42) centre dot H_2O (1),[Cu(L~2)Ni(rac-cth)](ClO_4)_2 centre dot 0.5 EtOH (2),and [(CuL~3)Ni(rac-cth)](ClO)_(42) centre dot H_2O (3).L~1,L~2,and L~3,are the dianions of diethyl 5,6,7,8,16,17-hexahydro-6,7-dioxo-15H-dibenzo[e,m][1,4,8,12]tetraazacyclopentadecine-13,19-dicarboxylate,diehtyl 5,6,7,8,15,16-hexahydro-6,7-dioxodibenzo[1,4,8,11]tetraazacyclotetracine-13,18-dicarboxylate,and diethyl 5,6,7,8,15,16-hexahydro-15-methyl-6,7-dioxodibenzo[1,4,8,11]tetraazacyclotetradecine-13,18-dicarboxylate,respectively,and rac-cth is rac-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane.The crystal structures of 1 and 2 were determined by single-crystal X-ray analysis.The Ni~(II) ion is pseudooctahedrally coordinated.The coordination geometry around the Cu~(II) ion in 2 is slightly distorted square planar,while that in 1 shows singificant distortion towards a tetrahedral structure.The temperature dependence of the magnetic susceptibility for 1 and 2 was analyzed by emans of the Hamiltonian H=-2JS_1centre dot S_2,leanding to J=-63.9 and -64.7 cm~(-1) for 1 and 2,respectively.