Question

Give reasons:
''The presence of nitro group $(-N{O}_2)$ at ortho/para positions increase the reactivity of haloarenes towards nucleophilic substitution reaction''.

Answer 1

This is because nitro group $(-N{O}_2)$ at o/p positions withdraw the electrons from the benzene ring which facilitates the attack of the nucleophile. The negative charge in the carbanion formed at o/p positions with respects to halogen atom is stabilized by the presence of nitro groups $(-N{O}_2)$ and resonance respectively.