Keto and Enol forms of Isobutryl acetic acid, 4- Amino benzoic acid and 4-Cyano benzoic acid

Metal complexes formed by the reactions of keto and enol forms of isobutryl acetic acid hydrazide[IBAH] , 4-amino benzoic acid hydrazide[4-ABAH] and 4-cyano benzoic acid hydrazide[4-CBAH] with manganese(II) and cobalt(II) sulphate ions were prepared and characterized by elemental analysis, conductance measurements, i.r., and electronic absorption spectra studies. The results showed that the hydrazides reacted with the metal salts in 1:2 molar ratio in all the complexes and acts as neutral bidentate ligands. The solubility test on the ligands and its metal(II) complexes revealed their solubility in ethanol and dimethylsulphoxide (DMSO). The molar conductance of the ligands and metal(II) complexes measured are indicative of their non-electrolytic nature. The infrared spectra of the hydrazide showed that ʋ(C=O), the carbonyl stretching mode called “amide1 ” band, the coupling between the in-plane bending ʋ(N-H) and ʋ(C-N) called the “amide II ” band and the stretching frequency for the amino group ʋ(NH2) all experienced shifts to lower wave numbers in the complexes suggesting the coordination of the moieties to the metal ions. The electronic absorption spectra of Co(II) complexes showed two absorption bands located at 23,250-19,300 c