Kinetic studies and mechanism on the permanganic oxidation of L-glutamine in strong acid medium in the presence and absence of silver (I)

The kinetic study and mechanism of the permanganic oxidation of L-glutamine in sulfuric acid has been carried out both in the absence and presence of silver (I) using a spectrophotometric technique. Activation parameters have been evaluated using the Arrhenius and Eyring plots. Mechanisms consistent with the observed kinetic data have been proposed and discussed. The overa ll rate expression for the oxidation may be written as -d[Mn(VII)]/dt = k(0)[L-Glutamine][Mn(VII)] In the presence of silver (I) the rate law is -d[Mn(VII)]/dt = Kk(c)"[L-Glutamine](0) [Ag+]/1 + K.[Ag+] + K[L-Glutamine] . [Mn(VII)] The reaction appears to involve an acid catalyzed and data showed role of w ater molecules in the rate-determining step is proton transfer which satisf ies Bunnett's theory. A mechanism satisfying the various kinetic parameters has been proposed. (C) 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 9 5-102, 1999.