Question

The bromination of aniline in water produces:

A. 2-bromoaniline

B. 4-bromoaniline

C. 2,4,6-tribromoaniline

D. 2,6-dibromoaniline

Answer 1

Hint: When an electrophile such as that of bromine replaces an atom attached to an aromatic ring, it is an electrophilic aromatic substitution reaction. The ortho and para positions of benzene are active towards this reaction while meta is inactive.

Complete step-by-step answer:

Aniline is an organic compound that has a phenyl group attached to an amino group, having molecular formula \[{C_6}{H_5}N{H_2}\]. The amino group is very reactive towards electrophilic substitution reaction as it is an electron donating group.

Aniline has several resonating structures and excess negative charge in its ortho and para positions of the benzene ring than that of the meta position. Therefore, the ortho and para positions are directive towards the electrophilic substitution reaction in case of aniline.

Aniline reacting with bromine water at room temperature produces a white-coloured precipitate called 2,4,6-tribromoaniline. This is because the polarity is developed within the bromine molecule where bromine then acts as an electrophile as it has slightly positive charge. It attacks the electron rich ortho and para positions of the aniline.

Hence, the correct option is (C).

Note: One important point is the aromaticity of the aromatic compound is not lost in electrophilic aromatic substitution reaction. If the electrophilic attack occurs at an angle of 180 degrees to the leaving group, then the reaction results in the inversion of configuration of the substrate in electrophilic aliphatic substitution reaction.