Friedel-Craft reaction as shown below is an example of

Electrophilic substitution reaction

The correct answer is Option (1) → Electrophilic substitution reaction

Core Concept

Friedel–Crafts alkylation is an electrophilic aromatic substitution (EAS) reaction. An electrophile (CH₃⁺) replaces a hydrogen atom on the benzene ring.

An electrophilic substitution reaction is an organic reaction where an electrophile (electron-seeking species) replaces a functional group, typically a hydrogen atom, on a molecule. Primarily occurring in aromatic compounds (Electrophilic Aromatic Substitution, or EAS), this process enables the substitution of benzene ring atoms using reagents like acids or Lewis acid catalysts to introduce functional groups.

Explanation of Each Option

(1) Electrophilic substitution reaction

In Friedel–Crafts alkylation, CH₃Cl reacts with AlCl₃ to generate CH₃⁺ electrophile. This electrophile attacks the aromatic ring and substitutes hydrogen. Since substitution occurs via electrophile, this is correct.

(2) Nucleophilic substitution reaction

In nucleophilic substitution, a nucleophile replaces a leaving group. Here, the attacking species is an electrophile, not a nucleophile. Hence, incorrect.

(3) Electrophilic addition reaction

Addition reactions break aromaticity. But Friedel–Crafts maintains aromatic stability through substitution. So this is incorrect.

(4) Nucleophilic addition reaction

No nucleophile is attacking, and aromatic ring is not undergoing addition. Hence incorrect.