Kinetic and mechanistic studies of oxidation of chloramphenicol by sodium metaperiodate using Rh(III)-chloride as homogeneous catalyst

SINGH, ASHOK KUMAR; Pradhan, Ranju ; Srivastava, Jaya ; Bala, Ritu Swamini; Yadav, Rupam ; Rahmani, Shahla

Abstract

The kinetics of oxidation of an antibiotic drug, chloramphenical(CHP) by NaIO4 in the presence of Rh(III) catalyst has been investigated in alkaline medium at 350C. The reaction shows first order kinetics with respect to [IO4-] and [Rh(III)]. The fractional positive order kinetics in [OH-] and [CHP] throughout their variations were observed. It was found that ionic strength and dielectric constant of the medium had no effects on the rate of reactions. There is no effect of [Cl-] in presence of Rh(III) chloride. The values of rate constants observed at four different temperatures were utilized to calculate various activation parameters. The species [IO4-] and [RhCl3(H2O)2OH]- are assumed as the reactive species of NaIO4 and Rh(III) respectively in alkaline medium. On the basis of kinetic results, spectroscopic information and activation parameters, a suitable mechanism and rate law for the oxidation of CHP has been proposed.


Keyword(s)

Kinetics, Reaction mechanism, Oxidation, Rhenium, Chloramphenicol


Full Text: PDF (downloaded 89 times)

Refbacks

  • There are currently no refbacks.
This abstract viewed 60 times