The imidazolium fluorochromate (IFC) oxidation of meta-and para-substituted anilines, in seven organic solvents, in the presence of p-toluenesulfonic acid (TsOH) is first order in IFC and TsOH and is zero order with respect to substrate. The IFC oxidation of 15 meta-and para-substituted anilines at 299-322 K complies with the isokinetic relationship but not to any of the linear free energy relationships; the isokinetic temperature lies within the experimental range. The specific rate of oxidizing species-anilines reaction (k 2 ) correlates with substituent constants affording negative reaction constants. The rate data failed to correlate with macroscopic solvent parameters such as ε r and E N T . A correlation of rate data with Kamlet-Taft solvatochromic parameters (α, β, π * ) suggests that the specific solute-solvent interactions play a major role in governing the reactivity, and the observed solvent effects have been explained on the basis of solute-solvent complexation.

The kinetics of oxidation of 15 para-and meta-substituted anilines by nicotinium dichromate (NDC) in different organic solvent media in the presence of p-toluenesulfonic acid (TsOH) has been investigated. The rate of the reaction is zero order with respect to substrate, first order in NDC, and is found to increase with increase in [TsOH]. The various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of the isokinetic relationship. The specific rate of oxidizing species-anilines reaction (k 2 ) correlates with Hammett's substituent constants affording negative reaction constants. The effect of paraand meta-substituents on the oxidation rates confirms to Swain et al.'s substituent constants F and R, both with negative reaction constants. The rate data failed to correlate with macroscopic solvent parameters such as ε r and E

Summary The imidazolium fluorochromate (IFC) oxidation of fifteen meta - and para-substituted anilines, in varying mole fractions of benzene in 2-methylpropan-2-ol as mixtures, in the presence of p-toluenesulfonic acid (TsOH) is first order in IFC and TsOH and zero order in substrate. The various thermodynamic parameters for the oxidation have been reported and discussed. The validity of the isokinetic relationship and various linear free energy relationships have been tested and discussed. The activation free energy data failed to correlate with macroscopic solvent parameters such as εr and E T N. Correlation of Δ G # with Kamlet–Taft solvatochromic parameters (α, β and π*) suggests that the specific solute–solvent interactions play a major role in governing the reactivity.

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Substitution reactions of 13 para-and meta-substituted anilines with benzenesulfonyl chloride in varying mole fractions of benzene in propan-2-ol have been investigated conductometrically. The second-order rate constants correlate well with pK a values of anilines and with the Hammett's equation. The negative Hammett reaction constant indicates the formation of an electron-deficient transition state. The rate data correlate satisfactorily with macroscopic solvent parameters such as relative permittivity, ε r , and polarity, E T N . Correlation of rate data with Kamlet-Taft solvatochromic parameters (α, β, π *) suggests that both the specific and nonspecific solute-solvent interactions influence the reactivity.