The kinetics of the reaction of 2,4-dinitro-1-chlorobenzene with various aromatic bases to give 2,4-dinitrodiphenylamines have been studied in alcohol, alcohol–acetonitrile, alcohol–dimethylformamide, and alcohol – dimethyl sulfoxide mixtures. No base catalysis has been observed under these conditions. ρ Values have been computed. In the reaction of o-chloro- and p-chloronitrobenzene with hydroxide in 50% dimethyl sulfoxide, the reactivity of both the isomers has been found to be identical, in contradiction to the previously reported observations.

The reactions between benzyl bromide and various bases as well as p-nitrobenzyl bromide and various bases have been studied in nitrobenzene-ethanol mixtures (80:20 v/v). The reaction is total second order as stated earlier. Comparison is made with the previous work on the same reaction with benzyl chloride and p-nitrobenzyl chloride.

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The kinetics of oxidation of cyclanols by Vv in acetic acid ‐ water mixtures at constant acidity is reported. The results are discussed in the light of I strain hypothesis. The postulated mechanism of Waters for cyclanol oxidation is also discussed with reference to this series of alcohols.

The kinetics of chlorination of toluene, o-methyl toluene, p-methyl toluene, m-methyl toluene, and m-chlorotoluene by chloramine-T(CAT) in aqueous acetic acid in the presence of HClOl have been studied. The reaction is first order with respect to [CAT] as well as [H+].The order with respect to the substrate is unity in the case of toluene and m-chlorotoluene, fractional in the case of o-methyl toluene and p-methyl toluene, and zero order in the case of m-methyl toluene. Nuclear halogenation has been observed with m-methyl toluene, while nuclear and side-chain halogenation for p-methyl toluene and o-methyl toluene, and sidechain halogenation for toluene and m-chlorotoluene are the pathways. An increase in the proportion of acetic acid accelerates the rate. Added acetate ions inhibit the reaction, and added p-toluene sulfonamide causes a pronounced retardation. A mechanism involving AcO+HCl as the important electrophile is discussed.

Kinetics of the reaction between some enolisable ketones (S) and trichloroisocyanuric acid (TCICA) in aqueous acid-acetic acid medium at 35 "C follow pseudo-zero-order and pseudo-first-order disappearance of [TCICA], in the absence and the presence of added CI-, respectively. The rate constants for the latter system exhibit a linear dependence each on [S], and [H+], and an increasing and limiting dependence on added [CI-1. The results are interpreted in terms of probable mechanisms involving (i) rate-determining enol formation from the conjugate acid of the ketone (SH') in the absence of added CI-and (ii) rate-determining interaction of SH' with the most effective molecular chlorine species produced by the hydrolysis of TCICA (rather than a rate-determining interaction of enol with Cl,) in the presence of added CI-, prior to the rapid steps of product formation.