Aryl halides are less reactive towards nucleophilic substitution reaction. Give four reasons.

Explanation

(i) Due to resonance, the electron pair of halogen atom are in conjugation with pi electrons of the ring. As a result C-X gets partial double bond character and bond breakage is difficult.
(ii) In haloarenes, halogen bonded carbon atom is `sp^(2)` hybridised. Hence breaking of C-X bond is very difficult.
(iii) Phenyl cation formed as a result of self-ionisation will not be stabilised by resonance.
(iv) Nuelcophilic substitution reaction is very less in electron rich arenes.