Question 58. The arenium ion which is not involved in the bromination of aniline is:
Answer: (3)
Explanation:
In aniline, the -\mathrm{NH}_{2} group is a strong activating group.
It is an \mathrm{o} and \mathrm{p} directing group.
During bromination, electrophilic attack occurs at the ortho and para positions.
Hence, arenium ions corresponding to ortho and para attack are formed.
An arenium ion formed by attack at the meta position is not involved in the reaction.
The meta arenium ion structure is: Nc1ccc[cH][cH+]1Br
Therefore, the arenium ion shown in option (3) is not involved.