Question

The arenium ion which is not involved in the bromination of Aniline is .

• A.

  

• B.

  

• C.

  

• D.

  

Answer 1

The Correct Option is C

Aniline's amine group activates the benzene ring, increasing its susceptibility to electrophilic substitution, particularly halogenation. The electron-donating -NH₂ group makes aniline brominate more readily than benzene.

Arenium ion intermediates dictate the reaction pathway and the site of bromination.

The question requires identifying the arenium ion intermediate *not* involved in aniline bromination. We will examine potential arenium ions:

The amine group's activating effect directs bromination primarily to the ortho and para positions. Consequently, arenium ions corresponding to these positions are predominantly formed.

Evaluation of options:

1. Options A and B: These represent ortho and para positions, consistent with typical electrophilic substitution in aniline.
2. Option C: This structure deviates from the typical arenium ions formed during electrophilic aromatic substitution in aniline, as it does not depict an activated ortho or para complex.
3. Option D: This structure aligns with common substitution patterns.

Thus, the arenium ion in Option C is not involved in the bromination of aniline.

The correct answer is Option C.