Chapter 2.15, Problem 4QQ

Interpretation Introduction

Interpretation:

The reactant that is needed to convert benzene to ethylbenzene in presence of ${\text{AlCl}}_{\text{3}}$ has to be chosen from the given options.

Concept Introduction:

Aromatic hydrocarbons undergo substitution reactions rather than addition reactions. Even though the aromatic hydrocarbon has double bonds in its structure, they undergo substitution reaction only because the double bonds are involved in delocalized bonding that is present in the ring system.

Alkylation:

Benzene undergoes alkylation reaction in presence of ${\text{AlCl}}_{\text{3}}$ as catalyst. The alkyl group from alkyl chloride gets substituted for a hydrogen atom in the benzene ring. The product obtained is alkylbenzene. The general reaction scheme can be given as,

Halogenation:

Benzene undergoes halogenation reaction in presence of ${\text{FeCl}}_{\text{3}}$ or ${\text{FeBr}}_{\text{3}}$ as catalyst to give halobenzene as product. The general reaction scheme can be given as,