Chapter 23, Problem 23.54P

Interpretation Introduction

(a)

Interpretation:

The complete mechanism and the major organic products for the given reaction are to be drawn.

Concept introduction:

Alkyl groups are ortho/para directors and a ring activator. An amino group is an ortho/para director under mildly acidic conditions, but it is a meta director under strongly acidic conditions.

If multiple substituents are attached to a phenyl ring, their activating/deactivating qualities are additive, and the regiochemistry tends to be governed by the most activating of those substituents.

In nitrating mixture ${\text{(HNO}}_{\text{3}}{\text{ + H}}_{\text{2}}{\text{SO}}_{\text{4}}\text{)}$, ${\text{NO}}_{\text{2}}{}^{\text{+}}$ is act as an electrophile which formed by proton transfer reaction between ${\text{HNO}}_{\text{3}}{\text{ and H}}_{\text{2}}{\text{SO}}_{\text{4}}$ followed by heterolysis. In an electrophilic addition step, the electrophile is added to electron rich benzene ring followed by electrophilic elimination step of ${\text{H}}^{\text{-}}$ to regain the aromaticity.

Interpretation Introduction

(b)

Interpretation:

The complete mechanism and the major organic products for the given reaction are to drawn.

Concept introduction:

Alkyl groups are ortho/para directors and a ring activator. An amino group is an ortho/para director under mildly acidic conditions, but it is a meta director under strongly acidic conditions.

If multiple substituents are attached to a phenyl ring, their activating/deactivating qualities are additive, and the regiochemistry tends to be governed by the most activating of those substituents.

In nitrating mixture ${\text{(HNO}}_{\text{3}}{\text{ + H}}_{\text{2}}{\text{SO}}_{\text{4}}\text{)}$, ${\text{NO}}_{\text{2}}{}^{\text{+}}$ is act as an electrophile which formed by proton transfer reaction between ${\text{HNO}}_{\text{3}}{\text{ and H}}_{\text{2}}{\text{SO}}_{\text{4}}$ followed by heterolysis. In an electrophilic addition step, the electrophile is added to electron rich benzene ring followed by electrophilic elimination step of ${\text{H}}^{\text{-}}$ to regain the aromaticity.