LINEAR TRINUCLEAR COPPER(II) COMPLEXES DERIVED FROM ACYCLIC HEXADENTATE SCHIFF BASE LIGANDS

摘要

New linear trinuclear copper(II) complexes, 1 and 2, derived from two acyclic hexadentate (N4O2) Schiff base ligands were synthesised and characterised. Each complex consisted of two ligand molecules sharing three copper(II) atoms and two anions. The X-ray crystal study of 2 revealed that the three copper(II) atoms form an exact linear arrangement having Cu(2) on the inversion centre and a Cu(1)-Cu(2) distance of 3.985 Angstrom. The central copper(II) is situated at the centre of the plane defined by an N2O2 square-planar coordination geometry. The coordination sphere (N3O) of each terminal copper(II) can be described as strongly distorted tetrahedral. The cyclic voltammograms of the complexes demonstrated two quasi-reversible reductions in which one is a redox process of two one-electron steps, associated with the two terminal copper(II) ions, and the second is the electron transfer process of the central copper(II). [References: 66]