Novel tetranuclear copper(II) complex of dicarboxyamine ligand: Syntheses, crystal structures and redox properties

The reaction between a new amino dicarboxylic ligand N-(2-carboxybenzomethyl)-β-alanine (H₂cbal) obtained by reducing the Schiff base N-(2-carboxybenzoimine)-β-alanine and copper(II) perchlorate afforded a novel tetracopper(II) complex. This tetracopper(II) complex shows unusual structure and novel core topology. The electrochemical study of the complex using cyclic voltammetrry in acetonitrile indicated the presence of a reversible one-electron reduction and two irreversible reductions at higher potentials. The EPR studies of the complex and one electron reduce form of the complex in acetonitrile at 115 K showed an axial signal with g_∥ > g_⊥ > 2.0 and an isotropic signal, respectively.