Question
Out of benzene, m-dinitrobenzene and toluene which will undergo nitration most easily and why?
Solution
Nitration of benzene involves the electrophile attack of 
(nitronium ion) on the ring. Since CH3 group has a +inductive effect, it activates the ring and electrophilic substitution readily takes place. On the other hand, it is most difficult in m-dinitrobenzene because of deactivating nature of nitro groups.
Thus ease of nitration decreases in the order Toulene> Benzene> m-Dinitrobenzene.
(nitronium ion) on the ring. Since CH3 group has a +inductive effect, it activates the ring and electrophilic substitution readily takes place. On the other hand, it is most difficult in m-dinitrobenzene because of deactivating nature of nitro groups.Thus ease of nitration decreases in the order Toulene> Benzene> m-Dinitrobenzene.
