Synthesis, Characterization and Extraction Properties of Four Unsymmetricall vic‐Dioximes and their Complexes with Nickel (II), Cobalt (II) and Copper (II)

Four new unsymmetrical vic‐dioximes: [L ¹ H ₂ ] N‐(4‐acetanilidyl)amino‐amphi‐glyoxime, [L ² H ₂ ] N‐(4‐acetanilidyl)amino‐anti‐glyoxime, [L ³ H ₂ ] N‐(2‐thiazolyl)amino‐amphi‐glyoxime and [L ⁴ H ₂ ] N‐(2‐thiazolyl)amino‐anti‐glyoxime were prepared by the reaction of amphi‐chloroglyoxime and anti‐chloroglyoxime with 4‐aminoacetanilide and 2‐aminothiazol in absolute ethanol. The preparation Ni(II), Co(II), and Cu(II) complexes of the amphi‐and anti‐isomers of these ligands are described.The ligands and their complexes were characterized by elemental analyses, IR, mass, H¹ and ¹³C NMR spectra and magnetic susceptibility measurements. Ligands complexing properties were studied by the liquid‐liquid extraction of selected alkali (Li⁺, Na⁺, K⁺, Cs⁺) and transition metals (Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺, Hg²⁺, Pb²⁺). It has been observed that all ligands show a high affinity to Cu²⁺ and Hg²⁺ ions, where as almost no affinity to alkali metals. The extraction equilibrium constants (K _ex) for complexes of ligands with Cu²⁺ and Hg²⁺ metal picrates between dichloromethane and water have been determined at 25°C.

Keywords:

• liquid‐liquid extractions
• vic‐dioximes
• transition metal complexes
• alkali cations