Question

Which of the following will give a faster solvolysis in aqueous ethanol more rapidly?

• A. Neither I nor II undergo ethanolysis
• B. Both undergo ethanolysis at the same rate
• C. I
• D. II

Answer 1

The correct option is D

II

Ethanolysis or solvolysis proceeds via the $S_{N}1$, for which the ideal substrates are tertiary halides (X = Cl, Br, I) or tertiary alcohols ( under the right conditions). Here both are secondary halides except that iodide is a far better leaving group than chloride. Although, the rate expression does not depend on the concentration of the leaving group, since the carbon – iodine bond is broken more easily, the latter undergoes a faster $S_{N}1$ reaction, and thus a faster ethanolysis.