Chapter 21, Problem 21.56P

Interpretation Introduction

(a)

Interpretation: The carbonyl compound and amine or alcohol needed to prepare the given compound are to be predicted.

Concept introduction: A carbonyl compound (aldehyde or ketone) reacts with $1^{\text{ο}}$ amine to yield imine, and reacts with $2^{\text{ο}}$ amine to yield enamine. The mechanism of both reactions are identical except for the last step. The last step for enamine formation involves loss of a proton from the adjacent $\text{C}-\text{H}$ bond, whereas the last step for imine formation involves loss of a proton from the $\text{N}$ atom itself.

Interpretation Introduction

(b)

Interpretation: The carbonyl compound and amine or alcohol needed to prepare the given compound are to be predicted.

Concept introduction: A carbonyl compound (aldehyde or ketone) reacts with $1^{\text{ο}}$ amine to yield imine, and reacts with $2^{\text{ο}}$ amine to yield enamine. The mechanism of both reactions are identical except for the last step. The last step for enamine formation involves loss of a proton from the adjacent $\text{C}-\text{H}$ bond, whereas the last step for imine formation involves loss of a proton from the $\text{N}$ atom itself.

Interpretation Introduction

(c)

Interpretation: The carbonyl compound and amine or alcohol needed to prepare the given compound are to be predicted.

Concept introduction: Acetals are the groups in which carbon atom is bonded with two $\text{OR}$ groups through single bonds. A carbonyl compound (aldehyde or ketone) yields an acetal, when it is treated with two equivalents of an alcohol or one equivalent of diol in the presence of strong acid. The reaction is reversible.

Interpretation Introduction

(d)

Interpretation: The carbonyl compound and amine or alcohol needed to prepare the given compound are to be predicted.

Concept introduction: Acetals are the groups in which carbon atom is bonded with two $\text{OR}$ groups through single bonds. A carbonyl compound (aldehyde or ketone) yields an acetal, when it is treated with two equivalents of an alcohol or one equivalent of diol in the presence of strong acid. The reaction is reversible.