Chapter 27, Problem 40E

Interpretation Introduction

(a)

Interpretation:

The main product of the mononitration of benzoic acid should be predicted.

Concept introduction:

The electrophilic aromatic substitution is the type of reaction in which an electrophile substitutes the hydrogen atom of benzene. A general electrophilic aromatic substitution reaction of benzene can be written as:

Where, ${\text{E}}^{+}$ is an electrophile.

The activating groups are the groups that have the ability to donate the electron density to the benzene ring.

The deactivating groups are the groups that have the ability to withdraw the electron density to the benzene ring. The ortho and para directing groups are the activating groups while meta direction groups are deactivating groups.

The nitration reaction takes place in the presence of nitric acid and sulphuric acid. In this reaction, the protonation of nitric acid occurs in order to produce the nitronium ion. The nitronium ion will attach on the benzene ring to form nitrobenzene. The general reaction is as follows:

Interpretation Introduction

(b)

Interpretation:

The main product of the monosulphonation of phenol should be predicted.

Concept introduction:

The electrophilic aromatic substitution is the type of reaction in which an electrophile substitutes the hydrogen atom of benzene. A general electrophilic aromatic substitution reaction of benzene can be written as:

Where, ${\text{E}}^{+}$ is an electrophile.

The activating groups are the groups that have the ability to donate the electron density to the benzene ring.

The deactivating groups are the groups that have the ability to withdraw the electron density to the benzene ring. The ortho and para directing groups are the activating groups while meta direction groups are deactivating groups.

The sulfonation takes place in the presence of sulphuric acid. In this reaction, sulfur trioxide is formed that acts as an electrophile. Sulfur trioxide will attach on the benzene ring to form the final product. The general reaction is as follows:

Interpretation Introduction

(c)

Interpretation:

The main product of the monobromination of $2\text{-nitrobenzaldehyde}$ should be predicted.

Concept introduction:

The electrophilic aromatic substitution is the type of reaction in which an electrophile substitutes the hydrogen atom of benzene. A general electrophilic aromatic substitution reaction of benzene can be written as:

Where, ${\text{E}}^{+}$ is an electrophile.

The activating groups are the groups that have the ability to donate the electron density to the benzene ring.

The deactivating groups are the groups that have the ability to withdraw the electron density to the benzene ring. The ortho and para directing groups are the activating groups while meta direction groups are deactivating groups.

Halogenation is the chemical reaction that involves the addition of one or more halogens to the compound. Bromination is the type of halogenations reaction that involves the addition of bromine to the compound. When bromine is added to a single position in the compound, the reaction is known as monobromination.

The bromination takes place in the presence of Lewis acid and bromine molecule. In this reaction, the bromonium ion is produced that acts as an electrophile. Brominium will attach on the benzene ring to form the final product. The general reaction is as follows: