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Question
Out of C6H5CH2Cl and C6H5CHClC6H5, which is more easily hydrolysed by aqueous KOH.
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Solution
C6H5CHClC6H5 is hydrolysed faster.
- The hydrolysis of an alkyl halide is a nucleophilic substitution reaction. For aryl halides, this occurs through the SN1 method, resulting in a carbocation.
- C6H5CH2Cl or benzyl chloride gives
a carbocation, while C6H5CHClC6H5 generates 
. - Out of I and II, carbocation II is more stable. Two attached phenyl rings on the carbon carry the positive charge.
- This leads to increased delocalisation of the positive charge and greater carbocation stability. This leads to faster formation of (II) and easier hydrolysis of the resulting halide than benzyl chloride.
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