Effect of Pressure on the Rate of Solvolysis. Hydrolysis of 1-Aryl-1-methylethyl Chlorides

Abstract
The effect of pressure on the hydrolysis rates of 1-aryl-1-methylethyl chlorides were investigated, and the activation volumes, ΔV0\eweq, were calculated. Electron-donating substituents in an aryl group gave less negative ΔV0\eweq values and electron-withdrawing substituents gave more negative ΔV0\eweq values. The observed values of ΔV0\eweq were found to correlate with σ+. These observations are interpreted in terms of the dependence of the degree of solvation at the transition state of the reaction. The temperature dependence of ΔV0\eweq is also discussed.