Question

Halogenation of benzene in presence of anhydrous $AlC{l}_3$ is an example of ______ reaction.

• A. nucleophilic substitution
• B. nucleophilic addition
• C. electrophilic substitution
• D. free radical substitution

Answer 1

The correct option is C electrophilic substitution

Halogenation of benzene in presence of $AlC{l}_3$ (anhy.) is electrophilic aromatic substitution reaction.
Electrophilic Substitution Mechanism for Halogenation:
1. Generation of an electrophile ($E^{+}$)
2. Formation of an arenium ion or sigma complex (intermediate).
3. Removal of proton $\left(H^{+}\right)$ from
the arenium ion.
Arenes (Aromatic hydrocarbons) react with halogens in the presence of a Lewis acid like anhydrous $FeC{l}_3,FeB{r}_{3}orAlC{l}_3$ to yield haloarenes as shown :