Arenes on treatment with chlorine in presence of ferric chloride as a catalyst undergo what type of reaction ?

Options

A. Electrophilic substitution
B. Nucleophillic substitution
C. Electrophilic addition
D. Nucleophillic addition

Answer

A

Explanation

Arenes on treatment with chlorine in presence of Lewis acid catalyst, ferric chloride or aluminium chloride and in the absence of light undergose halogenation. It involves electrophillic substitution reaction.

Mechanism of electrophilic substitution is as follows :
Stem I Generation of an electrophile.
`Cl-Cl+AlCl_(3)toCl^(+)+Cl^(delta-)-Cl_(3)toCl^(+)+[AlCl_(4)]^(-)` Chloronium ion
Step II Formation of carbocation (arenium ion)