Electrochemical Studies Of Novel 3,4-Dichloro-N-((5-ChloroPyridin-2-yl)Carbamothioyl)Benzamide Based On Its Complexes With Copper(II), Cobalt(II), Nickel(II) and Zinc(II) ions

Al-Riyahee, Ali A. A.; Murad, Diyar M.A.; Shenta, Ashwaq

doi:10.21608/ejchem.2021.64395.3383

Electrochemical Studies Of Novel 3,4-Dichloro-N-((5-ChloroPyridin-2-yl)Carbamothioyl)Benzamide Based On Its Complexes With Copper(II), Cobalt(II), Nickel(II) and Zinc(II) ions

Document Type : Original Article

Authors

¹ Basrah University. Iraq

² Basrah, Iraq.

10.21608/ejchem.2021.64395.3383

Abstract

The synthesis of novel N,Nʹ-disubstituted benzoyl thiourea ligand [3,4-dichloro-N-((5-chloropyridin-2-yl)carbamothioyl) benzamide] (L) is achieved in two steps. First step by refluxing KSCN with 3,4-dichloro benzoyl chloride in CH3CN solvent and the other step by the reaction of the resulting filtrate from the first step with 2-amino-5-chloropyridine. The copper(II), Cobalt(II), Nickel(II) and Zinc(II) chloride and acetate salts were coordinated with L ligand in the 1:1 and 1:2 mole ratios (M:L) in the solvent mixture of DMF/H2O or CHCl3/methanol to form the complexes with structural formulas {[LMCl2] and [L2M](CH3COO)2, M= Copper(II), Cobalt(II), Nickel(II) and Zinc(II) ions}. Two mole ratios of the starting materials, 1:1 and 1:2 (M:L) were experimented to form chloride complexes, the product was with structural formula [LMCl2] while acetate complexes with [L2M](CH3COO)2 formula are resulted with the same conditions. Ligand L and its complexes [LCuCl2], [LCoCl2], [LNiCl2], [LZnCl2], [L2Cu](CH3COO)2, [L2Co](CH3COO)2, [L2Ni](CH3COO)2 and [(L)2Zn](CH3COO)2 have been characterized by mass spectrometry, elemental analysis, magnetic moments, conductivity measurements, solubility test, UV-visible, FTIR, 1H and 13C NMR spectroscopies. Electrochemical studies were probed by using cyclic voltammetry technique(CV). The data reflect the quasi-reversible reductive nature for the Copper(II) complexes with one electron transfer process while Nickel(II) and Cobalt(II) complexes exhibited two consecutive irreversible reductive nature. The observed UV-visible, elemental analysis, molar conductivity, magnetic moment measurements and solubility test revealed that the metal ion in the all prepared complexes adopted four coordinated square planar structures and [LCuCl2], [LCoCl2], [LNiCl2], [LZnCl2], are formed as neutral complexes while [L2Cu](CH3COO)2, [L2Co](CH3COO)2, [L2Ni](CH3COO)2 and [(L)2Zn](CH3COO)2 adopted anion complexes. The observed magnetic moments show diamagnetic properties of Zinc(II) and Nickel(II) complexes while Copper(II) and Cobalt(II) appeared as paramagnetic species. FT-IR analysis confirmed the coordination sites between the central metal ion with ligand L through two sites, the nitrogen atom in pyridyl ring and the sulphur atom in C=S group < /p>

Keywords