Kinetic study of S-alkylation of 2-mercaptobenzimidazole by allyl bromide in the presence of potassium hydroxide

  • Wang M
  • Liu Y
  • 6


    Mendeley users who have this article in their library.
  • 3


    Citations of this article.


The S-alkylation (substitution on sulfur atom) of 2-mercaptobenzimidazole (MBI or ArSH) by allyl bromide (RBr) was successfully carried out in an aqueous solution of KOH/organic solvent two-phase medium. The reaction, which may take place either in the organic phase or on the interface, is greatly enhanced in the presence of KOH without the aid of quaternary salts as the catalyst to promote the reaction. No product was obtained from N-alkylation (substitution on nitrogen atom) during or after the reaction period by using a limited amount of allyl bromide (RBr) relative to that of MBI. Based on the experimental evidence, the kinetic behaviors and the characteristics of the reaction are sufficiently described by the pseudo-first-order rate law. The effects of the reaction conditions, including the agitation speed, the amount of KOH, volume of water, volume of dichloromethane, amount of allyl bromide, amount of 2-mercaptobenzimidazole, organic solvents and temperature on the conversion of allyl bromide and the apparent rate constants (kapp) were investigated in detail. Peculiar result is obtained in studying the effect of the volume of water on the conversion (or the reaction rate) in this work. Rational explanations are provided for the observed phenomena from experimental results. © 2008 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Author-supplied keywords

  • 2-Mercaptobenzimidazole (MBI) derivative
  • KOH effect
  • Kinetics
  • S-alkylation

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free