Write any two differences between SN\(_1\) and SN\(_2\) reactions. Which of the following compounds would undergo SN\(_1\) reaction faster and why?
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For SN\(_1\) reactions, the stability of the carbocation intermediate is crucial. Resonance-stabilized carbocations (like benzyl or allyl) favor the SN\(_1\) mechanism.
SN\(_1\) vs. SN\(_2\) Reactions: 1. SN\(_1\) reactions proceed in two steps, with the rate-determining step being carbocation formation. SN\(_2\) reactions are single-step processes involving backside attack on the carbon attached to the leaving group. 2. Polar protic solvents, which stabilize carbocations, favor SN\(_1\) reactions. Polar aprotic solvents, which do not heavily solvate the nucleophile, favor SN\(_2\) reactions by enhancing nucleophilic attack. Faster SN\(_1\) Reaction: The compound \( \text{C}_6 \text{H}_5 \text{CH}_2 \text{Cl} \) will react faster via SN\(_1\). This is due to the resonance stabilization of the resulting benzyl carbocation by the aromatic ring. In contrast, the cyclohexyl carbocation is less stable, leading to a slower SN\(_1\) reaction rate.
