Synthesis, structure, reactivity and electrochemical studies of oxovanadium(IV) chelates with some carboxyamide derivatives

Department of Chemistry, University Arts&. Science College, Kakatiya University, Warangal-506 001, Andhra Pradesh, India

E-mail: ravichemku@yahoo.co.in

Manuscript received 17 November 2005, accepted 30 June 2006

Oxovanadium(IV) chelates of (2\(Z\))-4-(2-acetylhydrazino)-4-oxobut-2-enoic acid (AOBER), 4-(2-acetylhydrazino)- 4-oxobutanoic acid (AOBAR), 2-[(2-acetylhydrazino)carbonyl]benzoic acid (ARCBR), (2\(Z\))-4-[(2-cyanophenyl)amino]-4- oxobut-2-enoic acid (COBER), 4-[(2-cyanophenyl)amino]-4-oxobutanoic acid (COBAR), 2-[{(2-cyanophenyl)amino) carbonyl}benzoic acid (CACBR), (2\(Z\))-4-(1H-benzimidazol-2-ylamino)-4-oxobut-2-enoic acid (BOBER), 4-(1Hbenzimldazol- 2-ylamino)-4-oxobutanoic acid (BOBAR) and 2-[(1H-benzimidazol-2-ylamino)carbonyl]benzoic acid (BYCBR) have been prepared and characterized by elemental analysis, magnetic moments, IR, electronic, NMR, ESR spectra and thermal studies. The magnetic moments and electronic spectral studies suggest square pyramid geometry to all the
oxovanadium(IV) complexes and distorted octahedral geometry to the vanadium(IV) complexes with O₄ and Cl₂O₄ as donor sets from the ligands. The electrochemical studies by cyclic volammograms produced Irreversible single oxidation peak for V^IV_V^V vs SCE ranging from 0.43-0.64 V rationalized by the basicity of ligands.