Application of nickel-catalysed reduction and azo dye reactions for the determination of tinidazole

A macrocyclic Schiff base nickel(ii) complex was synthesised via template synthesis by treating acetylacetone with 1,8-diaminonaphthalene in the presence of nickel chloride in a 2:2:1 ratio in an aqueous methanol solution at 75 °C for 30 min. It was characterised by elemental, infrared, proton and carbon nuclear magnetic resonance and mass spectral analysis and used as a catalyst for the reduction of tinidazole. The reduced tinidazole was treated with nitrous acid and 2-naphthol and the resulting azo dye was used for the spectrophotometric determination of the reduction product of tinidazole.