SYNTHESIS, SPECTROSCOPIC AND ELECTROCHEMICAL CHARACTERISATION OF NICKEL COMPLEXES WITH TWO N_2O TRIDENTATE, UNSYMMETRICAL SCHIFF BASE LIGANDS

摘要

Three nickel(II) complexes of general formula NiL_2, where L is a unsymmetrical N_2O ligand prepared by Schiff condensation of propane-1,3-diamine with salicylaldehyde (Hslp), 3-methoxysalicylaldehyde (Hmslp) or 2-hydroxy-1-naphthaldehyde (Hnlp) have been prepared. Characterisation of nickel complexes by spectroscopic methods indicates that they are six-coordinate with the amine group bound to the nickel centre. The accessibility of the +3 and +1 oxidation states for the complexes was evaluated by coupling electrochemical techniques and EPR spectroscopy.