Synthesis of the Schiff Base 3,10-Di[2-(2-pyridinyl)ethyl]-4,9-Dimethyl-5,8-diazadodeca-4,8-diene-2,11-dione and Its Complexes with Nickel(II) Perchlorate and Nitrate

Abstract

The Schiff base 3,10-di[2-(2-pyridinyl)ethyl]-4,9-dimethyl-5,8-diazadodeca-4,8-diene-2,11-dione, abbreviated here as Ddddd, has been synthesized, characterized by elemental analyses, IR and 1H NMR spectroscopy, and used to form complexes of the type [Ni(Ddddd)]X 2, X = ClO 4 −, NO 3 −. The complexes have been characterized via elemental analyses, molar conductivity, and magnetic susceptibility measurements, and IR and electronic absorption spectroscopy. While the ligand itself exists entirely as hydrogen-bonded enol-imine and keto-amine tautomers, it appears to coordinate to nickel(II) as a neutral ligand in its keto-imine form. The pyridinylethyl groups coordinate only weakly with the metal center.