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Allyl chloride is hydrolysed more readily than $n$-propyl chloride. Why?
Solution:
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Verified Answer
Allyl chloride on hydrolysis gives resonance stabilised carbocation while no resonance is observed in the carbocation formed by $n$-propyl chloride.
$$
\mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}_2 \mathrm{Cl} \stackrel{-\mathrm{Cl}^{-}}{\longrightarrow} \mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}_2+\mathrm{Cl}^{-}
$$
Allyl chloride
$$
\mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}_2^{+} \longleftrightarrow \mathrm{CH}_2-\mathrm{CH}=\mathrm{CH}_2
$$
(Resonance stabilised carbocation)
Hence, allyl chloride undergoes hydrolysis much faster than $n$-propyl chloride.
$$
\mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}_2 \mathrm{Cl} \stackrel{-\mathrm{Cl}^{-}}{\longrightarrow} \mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}_2+\mathrm{Cl}^{-}
$$
Allyl chloride
$$
\mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}_2^{+} \longleftrightarrow \mathrm{CH}_2-\mathrm{CH}=\mathrm{CH}_2
$$
(Resonance stabilised carbocation)
Hence, allyl chloride undergoes hydrolysis much faster than $n$-propyl chloride.
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