Chapter 18.3, Problem 3CC

Interpretation Introduction

Interpretation:

The mechanism for the reaction between Benzene and ${\text{D}}_{\text{2}}{\text{SO}}_{\text{4}}$ has to be illustrated.

Concept Introduction:

Electrophilic substitution reaction is a type of reaction in which a particular group or atom in a compound is replaced by electrophile. An electrophile is a species that is deficient of electrons.

Aromaticity is the property of organic compounds having cyclic and planar structure with $\left(\text{4n+2}\right)\text{π}$ electrons. It attributes to the stability of the compound. A compound that is aromatic is said to be highly stable.

Benzene is an electron rich Aromatic compound and undergoes electrophilic substitution reaction.

Carbocation formed in Benzene (arene) ring Carbon is known as arenium carbocation.

The delocalizing pi electrons neutralize the positive charge and in the process positive charge form again. The process of formation of carbocation and neutralizing the positive charge simultaneously occurs. The phenomenon of stabilizing and sustaining the positive charge on the benzene by delocalizing electrons is known as “resonance”.

The resonating structures stabilize the arenium carbocation and the structure formed by resonance is known as sigma complex.