Oxamido-bridged heterobinuclear copper(II)–nickel(II) complex and homotrinuclear nickel(II) complex with 2D supramolecular structure: synthesis, crystal structure, magnetic and spectroscopic properties

Abstract

The oxamido-bridged heterobinuclear copper(II)–nickel(II) complex, [Cu(oxbe)Ni(phen) 2]ClO 4·3H 2O ( 1) and homotrinuclear nickel(II) complex {[Ni(oxbe)] 2Ni(H 2O) 2}·2.5DMF ( 2) have been synthesized and characterized by means of elemental analysis, IR, EPR, and electronic spectra and magnetic susceptibility, where H 3oxbe is dissymmetrical ligand N-benzoato- N′-(2-aminoethyl)oxamido, phen=1,10-phenanthroline, DMF=dimethylformamide. Complex 1 has an extended oxamido-bridged structure consisting of planar copper(II) and octahedral nickel(II) ions. The χ M and μ eff versus T plots of 1 is typical of an antiferromagnetically coupled Cu(II)Ni(II) pair with a spin-doublet ground state, and magnetic analysis leads to J=−57.1 cm −1. The molecular structure of 2 is centrosymmetrical, with one octahedral nickel atom lying at an inversion center and two terminal Ni(II) atoms in approximately square planar environment. Through the hydrogen bonds and π–π stacking interactions, a 2D supramolecular structure is formed.