Chapter 23, Problem 23.45AP

Interpretation Introduction

(a)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with ${\text{Br}}_{\text{2}}$ is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water. The replacement of hydrogen atom attached to a carbon atom of electron-rich benzene ring by an incoming electrophile is known as electrophilic aromatic substitution reaction.

Answer to Problem 23.45AP

The product $2,4,6-\text{tribromo}-N-\text{methylaniline}$ is obtained in the reaction of $N-\text{methylaniline}$ with ${\text{Br}}_{\text{2}}$. The chemical reaction is shown below.

Explanation of Solution

When $N-\text{methylaniline}$ undergo electrophilic substitution reaction with a molecule of ${\text{Br}}_{\text{2}}$, it results in the formation of $2,4,6-\text{tribromo}-N-\text{methylaniline}$. It is a similar reaction which happens with phenol. The reaction is shown below.

Figure 1

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with ${\text{Br}}_{\text{2}}$ is $2,4,6-\text{tribromo}-N-\text{methylaniline}$ and its reaction is shown in Figure.1.

Interpretation Introduction

(b)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with benzoyl chloride is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water. The replacement of hydrogen atom attached to a carbon atom of electron-rich benzene ring by an incoming electrophile is known as electrophilic aromatic substitution reaction.

Answer to Problem 23.45AP

The product obtained in the reaction of $N-\text{methylaniline}$ with benzoyl chloride is $N-\text{methyl}-N-\text{phenylbenzamide}$. The reaction is shown below.

Explanation of Solution

When $N-\text{methylaniline}$ undergoes acylation reaction with benzoyl chloride, it results in the formation of amide that is $N-\text{methyl}-N-\text{phenylbenzamide}$. The reaction is shown below.

Figure 2

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with benzoyl chloride is $N-\text{methyl}-N-\text{phenylbenzamide}$ and its reaction is shown in Figure.2.

Interpretation Introduction

(c)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with benzyl chloride (excess), then dilute ${}^{-}\text{OH}$ is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water.

Answer to Problem 23.45AP

The product $N,N-\text{dibenzyl}-N-\text{methylbenzeneaminium}\text{hydroxide}$ is obtained in the reaction of $N-\text{methylaniline}$ with benzyl chloride (excess), then dilute ${}^{-}\text{OH}$. The reaction is shown below.

Explanation of Solution

When $N-\text{methylaniline}$ reacts with an excess of benzyl chloride followed by dilute ${}^{-}\text{OH}$ then ${\text{S}}_{\text{N}}\text{2}$ nucleophilic substitution reaction takes place which results in the formation of $N,N-\text{dibenzyl}-N-\text{methylbenzenaminium}\text{hydroxide}$. The reaction is shown below.

Figure 3

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with benzoyl chloride (excess), then dilute ${}^{-}\text{OH}$ is $N,N-\text{dibenzyl}-N-\text{methylbenzenaminium}\text{hydroxide}$ and its reaction is shown in Figure 3.

Interpretation Introduction

(d)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with $p-\text{toluenesulfonic acid}$ is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water.

Answer to Problem 23.45AP

The product $N,4-\text{methyl}-\text{N}-\text{phenylbenzenesulphonamide}$ is obtained in the reaction of $N-\text{methylaniline}$ with $p-\text{toluenesulfonic acid}$. The reaction is shown below.

Explanation of Solution

When $N-\text{methylaniline}$ reacts with $p-\text{toluenesulfonic acid}$, it results in the formation of sulfamide and product is known to be $N,4-\text{methyl}-\text{N}-\text{phenylbenzenesulphonamide}$. The reaction is shown below.

Figure 4

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with $p-\text{toluenesulfonic acid}$ is $N,4-\text{methyl}-\text{N}-\text{phenylbenzenesulphonamide}$ and its reaction is shown in Figure 4.

Interpretation Introduction

(e)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with ${\text{NaNO}}_{\text{2}}$ and $\text{HCl}$ is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water.

Answer to Problem 23.45AP

The product $2-\text{hydroxy}-1-\text{methyl}-1-\text{phenyldiazen}-1-\text{ium}$ is obtained in the diazotization reaction of $N-\text{methylaniline}$. The reaction is shown below.

Explanation of Solution

The reagents, ${\text{NaNO}}_{\text{2}}$ and $\text{HCl}$ are combined to form diazonium reagent but $N-\text{methylaniline}$ is secondary amine which does not undergo diazonium reaction. Therefore, the product obtained is $\text{N-nitroso N-methylaniline}$. The reaction is shown below.

Figure 5

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with ${\text{NaNO}}_{\text{2}}$, $\text{HCl}$ is $2-\text{hydroxy}-1-\text{methyl}-1-\text{phenyldiazen}-1-\text{ium}$ and its reaction is shown in Figure 5.

Interpretation Introduction

(f)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with excess ${\text{CH}}_{\text{3}}\text{I}$, heat, then ${\text{Ag}}_{\text{2}}\text{O}$ is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Hofmann elimination reaction occurs as an anti-elimination reaction. In this reaction, the starting material is quaternary ammonium hydroxide. When quaternary ammonium hydroxide is heated, $\text{β}$ elimination occurs to form an alkene, amines act as a leaving group.

Answer to Problem 23.45AP

The product $N,N,N-\text{trimethylbenzeneaminium}\text{hydroxide}$ is obtained in the reaction with excess ${\text{CH}}_{\text{3}}\text{I}$, heat, then ${\text{Ag}}_{\text{2}}\text{O}$. The reaction is shown below.

Explanation of Solution

Hofmann elimination reaction occurs as an anti-elimination reaction. In this reaction, the starting material is quaternary ammonium hydroxide. In the given case, when $N-\text{methylaniline}$ undergoes Hofmann elimination reaction, it results in the formation of $N,N,N-\text{trimethylbenzeneaminium}\text{hydroxide}$. The reaction is shown below.

Figure 6

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with excess ${\text{CH}}_{\text{3}}\text{I}$, heat, then ${\text{Ag}}_{\text{2}}\text{O}$ is $N,N,N-\text{trimethylbenzeneaminium}\text{hydroxide}$ and its reaction is shown in Figure 6.

Interpretation Introduction

(g)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with ${\text{CH}}_{\text{3}}\text{CH}=\text{O}$, $\text{NaBH}{\left(\text{OAc}\right)}_{\text{2}}$, and $\text{HOAc}$ in ${\text{ClCH}}_{\text{2}}{\text{CH}}_{\text{2}}\text{Cl}$, then $\text{KOH}$ is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water. Reductive amination reaction is the conversion of the carbonyl group to the amine or it converts one amine to newer amine.

Answer to Problem 23.45AP

The product, $N-\text{ethyl}-N-\text{methylaniline}$ is obtained in the reaction of $N-\text{methylaniline}$ with ${\text{CH}}_{\text{3}}\text{CH}=\text{O}$, $\text{NaBH}{\left(\text{OAc}\right)}_{\text{2}}$, and $\text{HOAc}$ in ${\text{ClCH}}_{\text{2}}{\text{CH}}_{\text{2}}\text{Cl}$, then $\text{KOH}$. The reaction is shown below.

Explanation of Solution

Reductive amination reaction is the conversion of the carbonyl group to the amine or it converts one amine to new amine. In the given case, when $N-\text{methylaniline}$ undergoes reductive amination reaction, it results in the formation of $N-\text{ethyl}-N-\text{methylaniline}$. The reaction is shown below.

Figure 7

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with ${\text{CH}}_{\text{3}}\text{CH}=\text{O}$, $\text{NaBH}{\left(\text{OAc}\right)}_{\text{2}}$, and $\text{HOAc}$ in ${\text{ClCH}}_{\text{2}}{\text{CH}}_{\text{2}}\text{Cl}$, then $\text{KOH}$ is $N-\text{ethyl}-N-\text{methylaniline}$ and its reaction is shown in Figure 7.

Interpretation Introduction

(h)

Interpretation:

The product obtained in the reaction of $N-\text{methylaniline}$ with chlorobenzene, ${\text{K}}^{+}t-{\text{BuO}}^{-}$, and a $\text{Pd}\left(\text{0}\right)$ catalyst is to be stated.

Concept introduction:

Amines are the organic compounds that are formed by replacement of hydrogen from ammonia with a substituent. It may be alkyl or aryl group. Amines are basic in nature because the nitrogen can donate its lone pairs and also the ability of the nitrogen to accept the proton in water.

Answer to Problem 23.45AP

The product $N-\text{methyl}-N-\text{phenylaniline}$ is obtained in the reaction of $N-\text{methylaniline}$ with chlorobenzene, ${\text{K}}^{+}t-{\text{BuO}}^{-}$, and a $\text{Pd}\left(\text{0}\right)$ catalyst. The reaction is shown below.

Explanation of Solution

When $N-\text{methylaniline}$ undergoes Buchwald Hartwig reaction that is used for $\text{C}-\text{N}$ bond formation through palladium-catalyzed reaction, it results in the formation of $N-\text{methyl}-N-\text{phenylaniline}$. The reaction is shown below.

Figure 8

Conclusion

The product obtained in the reaction of $N-\text{methylaniline}$ with chlorobenzene, ${\text{K}}^{+}t-{\text{BuO}}^{-}$, and a $\text{Pd}\left(\text{0}\right)$ catalyst is $N-\text{methyl}-N-\text{phenylaniline}$ and its reaction is shown in Figure 8.