Oxidations by Fe (Vi) : Kinetics of Oxidation of Unsaturated Carboxylate Anions

K. Laxmi Venkat Rao¹*, B. Sethuram¹ and T. Navaneeth Rao²

¹Department of Chemistry, Osmania University, College for Women, Koti, Hyderabad - 500 095 (India) ²Department of Chemistry, Osmania University, Hyderabad - 500 007 (India)

The kinetics of oxidation of fumarate, acrylate. cinnamate and maleate anions by Fe(VI) has been studied at pH 11.5 using orthophosphate buffer in the presence of periodate at 283K. The rate of oxidation decreases with increase in pH, in the pH range 9.8-11.9. The reaction followed Michaelis-Menton kinetics suggesting the formation of a cyclic intermediate between Fe(VI) and the substrate followed by its disproportionation in a slow step. The equilibrium constant (K) for the preequilibrium step and the rate constant (k) for the slow disproportionation step have been calculated. The order of reactivity of anions is fumarate

Kinetics of oxidation; Michaelis-Menton kinetics; activation parameters