NISCAIR Online Periodicals Repository

NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR)  >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.48A [2009] >
IJC-A Vol.48A(03) [March 2009] >


Title: Oxidation of mephenesin and guaifenesin with chloramine-B in hydrochloric acid medium: Design of kinetic model
Authors: Puttaswamy
Sukhdev, Anu
Keywords: Kinetics
Reaction mechanisms
Oxidations
Propane diols
Mephenesin
Guaifenesin
Issue Date: Mar-2009
Publisher: CSIR
IPC CodeInt. Cl. ⁸ CO7B33/00
Abstract: Kinetics of oxidation of mephenesin and guaifenesin by sodium N-chlorobenzenesulfonamide (CAB) have been investigated in HCl medium at 303 K. The oxidation behaviour is similar for both the substrates. The rate shows a first order dependence on both [CAB]₀ and [HCl], and is fractional in [substrate]₀. The orders individually in [H⁺] and [Cl⁻] are fractional. The variation of ionic strength and addition of the reduction product, benzenesulfonamide, has no significant effect on the reaction rate. The solvent isotope effect has been studied using D₂O, and the oxidation products have been identified. Composite activation parameters for the reaction have been determined from Arrhenius plots. Michaelis-Menten type of kinetics is observed and activation parameters for the rate limiting steps have also been computed. The proposed mechanism assumes the simultaneous catalysis by H⁺ and Cl⁻ ions. The reaction is found to be moderately faster in guaifenesin in comparison with mephenesin, which may be attributed to the involvement of methoxy and methyl groups of the substrate. The observed results have been explained by a plausible mechanism and the related rate law has been proposed.
Page(s): 339-345
ISSN: 0376-4710
Source:IJC-A Vol.48A(03) [March 2009]

Files in This Item:

File Description SizeFormat
IJCA 48A(3) 339-345.pdf158.15 kBAdobe PDFView/Open
 Current Page Visits: 769 
Recommend this item

 

National Knowledge Resources Consortium |  NISCAIR Website |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2012 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 622541 since 06-Feb-2009  Last updated on 13-Nov-2014Webmaster: nopr@niscair.res.in