Oxidation of L-arginine by manganese(VII) in concentrated sulfuric acid medium

Kinetics and mechanism of manganese(VII) oxidation of L-arginine has been s tudied in aqueous sulfuric acid medium. Various hypotheses for the mechanis m of acid catalysis have been tested and it has been found that rate is rel ated to the activity of water in accord with Bunnett's hypothesis. The ener gy and entropy of activation and frequency factor have been calculated usin g the Eyring and Arrhenius plots. Mechanisms in agreement with the observat ions are reported. The experimental rate law for the reaction was found to be -d[Mn(VII)]/dt = k(o)[L-Arginine][Mn(VII)] The reaction appears to involve an acid catalysis and the data showed the r ole of water molecules in the rate-determining step facilitating proton tra nsfer which satisfies Bunnett's theory.