A Kinetic Study of the Friedel-Crafts Phenylsulfonylation and p-Tosylation of Naphthalene in Nitrobenzene

Abstract

The sulfonylation reactions of naphthalene with phenylsulfonyl or Ptgsyl chloride in the presence of aluminum chloride in nitrobenzene have been stgdied kinetically.
It was found that the rate of the reaction is proportional to the coneentrations of three with the following mechanism.
RSO, Cl + AICI, . O, NCeHs t RSOkCl, AICIs + 02NC, H,
RSO2Cl. AICIs. RSO20, AICI, C
ArH+RSOstw, AICIS ArSO2R. AICIg+HCI
By the application of steady state approximation to the unst-ab. e intermadiate (RSO2ew. AICIP)in tr abo eM mechanism, rate equation can be expressed as follows.
Rate, f pr, duct frmati n
where
Dependence of rate constant on initial naphthalene concentration was interpreted in terms of the ratio k2/k-1.
Activation energies and activation entropies were aHptTigkcaiLmgi tiS =rr.9e u ancl respectively. d, H19kca1/m, 1, dS7e, u. for phenylsu1fonylation at, sylation