ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 19, Number 3
JKCSEZ 19(3)
June 20, 1975 

Rates of reactions of methanesulfonyl chloride with various substituted anilines have been measured in methanol. Substituent effects in aniline are found to be linearly correlated with pKa(Brφnsted relation with β = 0.84) and ρ(Hammett equation with ρ = -2.46) respectively. The results are interpreted in terms of degree of bond-formation at the transition state, which was found to have progressed relatively further. The rates for o-methylaniline deviated from the Brφnsted plot established by meta and para substituted anilines because of a steric effect of ortho position in aniline. Activation parameters, ΔH≠ and ΔS≠ have also been determined. The enthalpy of activation showed a regular variation in that electron donating substituents in the p-substituted aniline decrease ΔH≠ and increase the negative value of ΔS≠.