Direct Electrochemical Synthesis of Mono, Bi And Polynuclear Complexes of Some Hydrazide and Hydrazone Derivatives

Abstract

Transition metal complexes of mono-, di- and tetrahydrazides and their hydrazones have been prepared by electrochemical techniques using the metal as a sacrifical anode. The electrochemical oxidation of Co, Ni and Cu in non-aqueous (acetone) solution ofbenzoic hydrazide (HBzH), malonic dihydrazide HiMH), 1,1,3,3' - propanetetracarbohydrazide (I-LiPTCH), acetyl sal-isoylhydrazone (FLASH), benzolsalisolyhdrazone (H2BSH), 1,3 - malonyldisalisoylhydrazone (H4MDSH) and 1,1,3,3' -propanetetrasalisoyl - tetracarbohydrazone (HsPTSTCH) gave 1:2, 1:1, 2:1 and 4:1 (metal: ligand) ratio in good yields. When a neutral donor ligand such as 1,10-phenanthroline or triphenylphosphine is present in solution, adducts were formed. Since the ligand (PTSTCH) has four hydrazone groups it may act in an ONO tridentate fashion from each side with one of the four metal ions forming a polynuclear complex coordinating through the phenolic oxygen, the azomethine nitrogen and the enolic oxygen of the carbonyl group. The complexes have been characterized by elemental analysis, infrared, electronic spectra, magnetic measurements and thermal (DTA, TG and DTG) studies.