The Formation Constants Of Certain Transition Metal Complexes 4-[(E)-{(2E)-[(3E)-3-(Hydroxyimino)Butan-2-Ylidene]Hydrazinylidene}Methyl]Phenol Were Determined In A Mixed Solvent System.

Abstract

A novel ligand, diacetyl monoximehydrazide-4-hydroxybenzaldehyde (HDM HpHB), was synthesized and reported for the first time in this study. Its acidity constant was determined potentiometrically in a mixed solvent system (dioxane + water) at different ionic strengths. Due to the interest in the ligand's coordinating behavior with various transition metal ions, similar potentiometric studies were conducted to determine the metal-ligand formation constants. The results indicated that the ligand behaves as a monobasic acid, despite having two potentially dissociable protons (the oximino and phenolic protons). The nature of this monobasic character was further examined. Metal complexes with Co(II), Ni(II), Cu(II), and Zn(II) revealed that the most stable species formed was the ML2 complex.