A Green approach to the transition metal ion catalyzed oxidation of some industrially important alcohols using Ammonium metavanadate in acidic medium
Environmentally hazardous metals like Os(VIII), Cr(VI) and Ru in different oxidation states have been used on a large scale to catalyze the oxidation of alcohols. As a green initiative, we have used relatively less harmful and less costly transition metal ions to study the kinetics of oxidation of different types of industrially useful alcohols using Ammonium metavanadate in acidic medium. The oxidation was studied under first order kinetic conditions with respect to the oxidant and the progress of the reaction was monitored iodometrically. The thermodynamic activation parameters were determined from the increase of oxidation rate with temperature. The oxidation rates of the transition metal on catalyzed oxidation of alcohols have been determined. The relative oxidation rates of the alcohols under study have been correlated with their structural and isomeric characteristics. The sequences of catalytic efficiencies of metal ions has been determined for each alcohol on the basis of Irving-Williams order of stability of the metal complexes formed during the course of the reaction. Suitable reaction mechanisms have been suggested for the oxidation of alcohols. Transition metal ions can effectively oxidize alcohols to the corresponding carbonyl compounds and thus the transition metal ion catalyzed oxidation promises to be an environmentally friendly process.