The alkaline hydrolysis of some benzoic esters in dioxan-water mixtures as well as that of benzyl benzoate in acetone-water has been studied. The observations indicate a group influence consistent with the ease of formation of the transition state by interaction between the hydroxyl ion and the carbonyl group of the ester in the rate determining step. The influence of dielectric constant is what might be expected for an ion-dipole reaction but specific solvent influences cannot be excluded.

In continuation of our studies on ester hydrolysis, the kinetic studies of cinnamates are reported. A close correlation between benzoates previously reported and cinnamates is noticed. The differences in the reactivity of these esters are explained.

In continuation of our studies on ester hydrolysis, the kinetics of alkaline hydrolysis of succinates are reported. The rate constants of the first and second step of hydrolysis have been evaluated. A comparative study of the structural and solvent influences on the succinates is made.

The study of hydrolyses of the diesters of benzene dicarboxylic acids as a consecutive reaction and of the sodium salt of the half ester in mixed solvents clearly indicates that both in the first and in the second stage the reaction is only of the ion-dipole type. Calculations of the dimensions of the reactant species show that the most reasonable values are given by the Laidler approach while the Ingold calculations probably give the dimensions of the solvated transition state.

The kinetics of the reaction of diols with various hydrogen halides is discussed. The reaction involves neighbouring group participation as postulated earlier, the rate of substitution being faster for a heavier nucleophile. The reactions are inert in aqueous systems as the X⁻ nucleophilicity becomes negligible as compared to the nucleophilicity of water. At and above 7·5 per cent. water these reactions do not occur. Variation of dielectric constant also notably affects the process.

The kinetics of the reaction of 2, 4-dinitro-1-bromo benzene and 2, 4-dinitro-1-iodo benzene with various aromatic bases has been studied in alcohol, alcohol-acetonitrile, alcohol-dimethylformamide and alcohol-dimethyl sulfoxide mixtures. The halogen order observed is Br > Cl > I. No base catalysis has been observed under these conditions. ρ values have been computed. Mechanism of the aromatic nucleophilic substitution is discussed.

The reactions of benzyl chloride,p-methyl benzyl chloride,p-chloro benzyl chloride, benzyl bromide andp-nitro benzyl bromide with aromatic and heterocyclic bases have been studied in carbon tetrachloride-phenol mixtures. The reactions of amines and pyridine with benzylchloride andp-methyl benzyl chloride have been extended to solvent mixtures like benzene-phenol, nitrobenzene-phenol, nitro-benzene-ethanol and carbontetrachloride-ethanol mixtures and those of amines and pyridine with benzyl bromide andp-nitrobenzyl-bromide have been extended to DMF-phenol mixtures. The results are discussed in the light of basicity, nucleophilicity, electronic, steric and medium effects.