At room temperature
methanesulphonyl chloride reacts more rapidly than ethanesulphonyl chloride in
solvolysis by ethanol. Their rates of reaction with methanol are approximately
equal while ethanesulphonyl chloride is the more reactive in hydrolysis. The enthalpies
and entropies of activation have been determined for the solvolysis of
ethanesulphonyl chloride in mixtures of ethanol with benzene, carbon
tetrachloride, or 2,2,4-trimethylpentane. A comparison of the excess enthalpies
and entropies of mixing in the formation of these solvents with the
corresponding parameters for reaction shows that the effects on reaction rate
are not due merely to the modification of the initial state of the system. The
effect of the polar aprotic solvent nitrobenzene on the rate of reaction with
methanol is attributed to an increase in the nucleophilic tendency of the
methanol rather than to solvation of the reactive centre in the transition
state.
