The kinetics of the reaction of benzyl bromide with thiourea was studied in different pure (protic and aprotic) solvents and the rate data was correlated using linear multiple regression analysis. From the regression coefficients which describe the susceptibility of rate to different solvent parameters, information regarding the solvent-reagent, and the solvent-intermediate interactions was obtained and solvation models were proposed.Applicability of the Swain-Scott free energy relationship was tested using different sulphur nucleophiles in acetonitrile solvent and the nucleophilicity constant of N-acetylthiourea was computed as 2.74 from the regression line.

Conductance of quinolinium dichromate has been measured in water and N,N-dimethyl formamide mixtures over the complete compositional range. The limiting molar conductance Λo and the association constant of the ion pair, K A, have been computed using the Shedlovsky equation. Λo increases with an increase in the proportion of water in the solvent mixture. The Kraus−Bray equation has also been used to correlate the limiting molar conductance data, and the dissociation constant of the ion pair, K C, has been computed. The results have been discussed in terms of ion−solvent interactions.

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Oxidation of lactic acid, α-hydroxyphenyllacetic acid and its 4-chloro derivative with quinolinium dichromate (QDC) in 30% (v/v) aqueous acetic acid at 303 K are first order in QDC and first-order in hydroxy acids. The reactions are acid-catalyzed and a medium of low dielectric constant favours the oxidation. The products are the corresponding aldehydes. Thermodynamic parameters are evaluated and a mechanism involving a C-C bond cleavage is proposed.

The oxidation of ortho-, meta-, and para-substituted phenols by Quinolinium Dichromate (QDC) to the corresponding Quinones in aqueous acetic acid medium is first-order with respect to [QDC] and [phenol]. There is no effect of added Quinoline on rate. The reaction is acid catalyzed. A medium of low dielectric constant favors the oxidation process, and the rate of the oxidation process changes with change in the ionic strength of the medium. Electron releasing groups on the benzene ring enhance the rate of oxidation, while electron withdrawing groups retard, compared to the unsubstituted phenol. A correlation exists between log k 2 and , the Hammett's substituent constant, with a slope of Ϫ 3.79 at 303 K. Analysis of the rate data using I and R values indicate that both inductive and resonance effects of the substituents equally influence the rate of the reaction. The free energy of activation, ⌬G ϶ , is linearly correlated with . A probable mechanism is proposed.