Chapter 18, Problem 18.41P

Interpretation Introduction

(a)

Interpretation:

How the given amine can be synthesized from a ketone or an aldehyde is to be shown.

Concept introduction:

Aldehydes and ketones react with ammonia and primary amines to form an imine. The reaction occurs as a nucleophilic addition of the amine to the carbonyl carbon followed by protonation and elimination of ${\text{H}}_{\text{2}}\text{O}$ under mildly acidic conditions. The imine can be reduced to the corresponding amine with ${\text{NaBH}}_{\text{4}}$ via nucleophilic addition of a hydride ion to the imine carbon.

Interpretation Introduction

(b)

Interpretation:

How the given amine can be synthesized from a ketone or an aldehyde is to be shown.

Concept introduction:

Aldehydes and ketones react with secondary amines to form an enamine. Since there is only one hydrogen attached to the nitrogen atom, imine formation cannot occur. Instead, a proton from the $\text{α}$-carbon is extracted to form an enamine. The reaction occurs as a nucleophilic addition of the amine to the carbonyl carbon followed by protonation and elimination of ${\text{H}}_{\text{2}}\text{O}$ under mildly acidic conditions. The enamine can be reduced to the corresponding amine with ${\text{NaBH}}_{\text{4}}$ via the nucleophilic addition of a hydride ion to the imine carbon.

Interpretation Introduction

(c)

Interpretation:

Steps to synthesize amine from a ketone or aldehyde is to be proposed

Concept introduction:

Aldehydes and ketones react with ammonia and primary amines to form an imine. The reaction occurs as a nucleophilic addition of the amine to the carbonyl carbon followed by protonation and elimination of ${\text{H}}_{\text{2}}\text{O}$ under mildly acidic conditions. The imine can be reduced to the corresponding amine with ${\text{NaBH}}_{\text{4}}$ via nucleophilic addition of a hydride ion to the imine carbon.