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The reaction rates of substituted quinolines(6-CH3C9H7N, C9H7N) with p-substituted benzoylchlorides(p-CH3,p-H, p-NO2) have been measured by conductometry in acetonitrile, and the rate constants are determined at various temperatures(10, 15, 20, 25℃) and pressures(l, 200, 500, 1000bar). From the values of rate constants, the activation parameters(Ea,ΔV≠,ΔH≠,ΔS≠, and ΔG≠) and the pressure dependence of Hammett p values were determined. The rate constants increase as a function of temperatures and pressures, and are further increase by introduction the electron donor substituents in nucleopbile(p-CH3) or electron acceptor(p-NO2) substituents in substrate. The activation volume, and the activation entropy are all negative. Hammett p values are also negative for nucleophile (px) and positive for the substrate (py) over the pressure range studied. The results of kinetic studies for pressure and substituent show that these reactions proceed in typical SN2 reaction mechanism and "associative SN2" in which bond formation favored with increasing pressures.
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