Chapter 23, Problem 23.20P

(a)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a secondary arylamine with molecular formula ${\text{C}}_{\text{7}}{\text{H}}_{\text{9}}\text{N}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

If nitrogen atom of amine group is attached only to alkyl groups, then it is an aliphatic amine.

If nitrogen atom of amine group is attached to at least one aryl groups, then it is an aromatic amine.

If nitrogen atom of amine group is a part of an aromatic ring, then it is a heterocyclic aromatic amine.

If nitrogen atom of amine group is a part of a ring, then it is a heterocyclic amine.

Explanation of Solution

Given molecular formula is ${\text{C}}_{\text{7}}{\text{H}}_{\text{9}}\text{N}$.

The compound is secondary amine so the nitrogen of amine group should be bonded with two carbon containing groups. Also this nitrogen atom must attach to an aryl group.

Therefore,

Structural formula of a secondary arylamine with molecular formula ${\text{C}}_{\text{7}}{\text{H}}_{\text{9}}\text{N}$ is,

(b)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a tertiary arylamine with molecular formula ${\text{C}}_8{\text{H}}_{11}\text{N}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

If nitrogen atom of amine group is attached only to alkyl groups, then it is an aliphatic amine.

If nitrogen atom of amine group is attached to at least one aryl groups, then it is an aromatic amine.

If nitrogen atom of amine group is a part of an aromatic ring, then it is a heterocyclic aromatic amine.

If nitrogen atom of amine group is a part of a ring, then it is a heterocyclic amine.

Explanation of Solution

Given molecular formula is ${\text{C}}_8{\text{H}}_{11}\text{N}$.

The compound is secondary amine so the nitrogen of amine group should be bonded with three carbon containing groups. Also this nitrogen atom must attach to an aryl group.

Therefore,

Structural formula of a tertiary arylamine with molecular formula ${\text{C}}_8{\text{H}}_{11}\text{N}$ is,

(c)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a primary aliphatic amine with molecular formula ${\text{C}}_7{\text{H}}_9\text{N}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

If nitrogen atom of amine group is attached only to alkyl groups, then it is an aliphatic amine.

If nitrogen atom of amine group is attached to at least one aryl groups, then it is an aromatic amine.

If nitrogen atom of amine group is a part of an aromatic ring, then it is a heterocyclic aromatic amine.

If nitrogen atom of amine group is a part of a ring, then it is a heterocyclic amine.

Explanation of Solution

Given molecular formula is ${\text{C}}_7{\text{H}}_9\text{N}$.

The compound is primary amine so the nitrogen of amine group should be bonded with only one carbon containing group. Also this nitrogen atom must attach to an alkyl group.

Therefore,

Structural formula of a primary aliphatic amine with molecular formula ${\text{C}}_7{\text{H}}_9\text{N}$ is,

(d)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a chiral primary amine with molecular formula ${\text{C}}_4{\text{H}}_{11}\text{N}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

Chiral carbon: A carbon is said to be chiral carbon if it is bonded to four different substituents.

If nitrogen atom of amine group is attached only to alkyl groups, then it is an aliphatic amine.

If nitrogen atom of amine group is attached to at least one aryl groups, then it is an aromatic amine.

If nitrogen atom of amine group is a part of an aromatic ring, then it is a heterocyclic aromatic amine.

If nitrogen atom of amine group is a part of a ring, then it is a heterocyclic amine.

Explanation of Solution

Given molecular formula is ${\text{C}}_4{\text{H}}_{11}\text{N}$.

The compound is primary amine so the nitrogen of amine group should be bonded with only one carbon containing group. Since the compound is chiral, one carbon atom should be bonded with four different groups.

Therefore,

Structural formula of a chiral primary amine with molecular formula ${\text{C}}_4{\text{H}}_{11}\text{N}$ is,

Chiral carbon is labelled with asterisk (*) as above.

(e)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a tertiary heterocyclic amine with molecular formula ${\text{C}}_6{\text{H}}_{11}\text{N}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

If nitrogen atom of amine group is attached only to alkyl groups, then it is an aliphatic amine.

If nitrogen atom of amine group is attached to at least one aryl groups, then it is an aromatic amine.

If nitrogen atom of amine group is a part of an aromatic ring, then it is a heterocyclic aromatic amine.

If nitrogen atom of amine group is a part of a ring, then it is a heterocyclic amine.

Explanation of Solution

Given molecular formula is ${\text{C}}_6{\text{H}}_{11}\text{N}$.

The compound is secondary amine so the nitrogen of amine group should be bonded with three carbon containing groups. Also this nitrogen atom must be one of the atoms of the ring since the compound is a heterocyclic amine.

Therefore,

Structural formula of a tertiary heterocyclic amine with molecular formula ${\text{C}}_6{\text{H}}_{11}\text{N}$ is,

(f)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a trisubstituted primary arylamine with molecular formula ${\text{C}}_9{\text{H}}_{13}\text{N}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

If nitrogen atom of amine group is attached only to alkyl groups, then it is an aliphatic amine.

If nitrogen atom of amine group is attached to at least one aryl groups, then it is an aromatic amine.

If nitrogen atom of amine group is a part of an aromatic ring, then it is a heterocyclic aromatic amine.

If nitrogen atom of amine group is a part of a ring, then it is a heterocyclic amine.

Explanation of Solution

Given molecular formula is ${\text{C}}_9{\text{H}}_{13}\text{N}$.

The compound is primary amine so the nitrogen of amine group should be bonded with only one carbon containing group. Also this nitrogen atom must attach to an aryl group that has three substituents.

Therefore,

Structural formula of a trisubstituted primary arylamine with molecular formula ${\text{C}}_9{\text{H}}_{13}\text{N}$ is,

(g)

Interpretation Introduction

Interpretation:

Structural formula has to be drawn for a chiral quaternary ammonium salt with molecular formula ${\text{C}}_{\text{6}}{\text{H}}_{\text{16}}\text{NCl}$.

Concept introduction:

In chemistry Structure is the arrangement of chemical bonds between atoms in a molecule, specifically which atoms are chemically bonded to what other atoms with what kind of chemical bond.

Amines are the derivatives of ammonia $\left(N{H}_3\right)$ with one or more of the hydrogens replaced with a substituent such as an alkyl group.

Depending on the number of carbon side chain of the amide, different types of amides can form.

Chirality: It refers to an atom in a molecule that contains four different substituents.

If nitrogen atom in amine group is attached with four atoms or group of atoms then the compound can be named as the salt of the corresponding amine (quaternary ammonium salt).

Explanation of Solution

Given molecular formula is ${\text{C}}_{\text{6}}{\text{H}}_{\text{16}}\text{NCl}$.

The compound is quaternary ammonium salt so the nitrogen of amine group should be bonded with group of atoms. Since the compound is chiral, the four groups attached to this nitrogen should be different.

Therefore,

Structural formula of a chiral quaternary ammonium salt with molecular formula ${\text{C}}_{\text{6}}{\text{H}}_{\text{16}}\text{NCl}$ is,

Chiral atom is labelled with asterisk (*) as above.