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Question
Haloarenes are less reactive than haloalkanes and haloalkenes. Explain.
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Solution
In haloarenes, the electron pairs on halogen atom are in conjugation with π-electrons of the ring.
C-Cl bond acquires a partial double bond character due to resonance. As a result, the bond cleavage in haloarene is difficult than haloalkane and therefore, they are less reactive towards nucleophilic substitution reaction.
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