Thermodynamic Study Of Acid Catalysed Oxidation Of Sulphur Containing Amino Acids By Oxo (Salen) Chromium (V) Ion
نویسنده
چکیده
The kinetics and thermodynamics of oxidation of Methionine and Ethionine by oxo (salen) chromium (V) ion have been investigated by spectrophotometric method in aqueous medium. The presence of water facilitates ligation of water to the Cr centre and forms an active oxidant [H2O (salen) Cr=O] + .The reaction is found to be first order each in the oxidant and the substrate. The presence of H + ions accelerates the reaction rate. It is found to be first order with respect to H + ion. The second order rate constant increases with increase in the water content in the reaction medium. The reaction is carried out at different temperatures and various thermodynamic parameters for the oxidation have been reported. From the kinetic data and thermodynamic parameters, a mechanism involving direct oxygen transfer from oxidant [H2O-(salen) Cr=O] + to the substrate has been proposed as a suitable mechanism for the reaction.
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