Synthesis and properties of μ-oxamido heterobinuclear Cu(II)-M(II) complexes (M = Ni, Co, Cu, Mn)

Four novel mu -oxamido heterobinuclear complexes, [Cu(oxbp) M(phen)(2)](ClO4)(2) (oxbp = N,N ' -bis(2-aminoalkyl)oxmido and its diethyl derivative, phen = 1, 10-phenanthroline) have been synthesized and characterized. Based on IR, elemental analyses, electronic spectra and conductivity measurements, these complexes are proposed to have an oxamido-bridged structure and consist of Cu(II) in a planar environment and M(II) in a distorted octahedral environment. The complex [Cu(oxbp)Ni(phen)(2)](ClO4)(2). 2H(2)O has been characterized by variable-temperature magnetic susceptibility measurements (4-300 K) and the susceptibility data were least squares fit to the susceptibility equation derived from the spin Hamiltonian operator (H) over cap= -2J (S) over cap (1)(S) over cap (2). The exchange interaction parameters are J = -0.53 cm(-1), g = 2.1. This indicates an anti-ferromagnetic spin exchange interaction between the adjacent metal ions.