Nickel(II) and Copper(II) Complexes of β-Ketoamines Derived from β-Diketones and Aromatic Amines

Abstract

Abstract Nickel(II) and copper(II) complexes of β-ketoamines derived from acetylacetone or benzoylacetone and aromatic amines have been newly synthesized and characterized. The aromatic amines included aniline, o-, m- and p-toluidine, o,o′-dimethylaniline, o,o′-diethylaniline, o-, m- and p-chloroaniline, and α- and β-naphthylamine. The configurations of these complexes in pyridine have been examined and compared with those in non-donor solvents. All these complexes are considered to be square-planar in non-donor solvents and in the solid state. The nickel-(II) complexes of the o,o′-disubstituted derivatives do not combine with pyridine molecules, whereas the corresponding copper(II) complexes readily combine with the pyridine molecule. The difference between nickel(II) and copper(II) ions is discussed in terms of the bonding nature of the metal ions. The β-ketoamines and salicylideneimines are also compared.