Chapter 22, Problem 22.41P

Interpretation Introduction

(a)

Interpretation:

The synthesis of the given compound from a $\beta \text{-}$ keto ester is to be predicted. The synthesis of the corresponding $\beta \text{-}$ keto ester is to be predicted.

Concept introduction:

The decarboxylation reaction is a type of reaction in which a compound loses ${\text{CO}}_{\text{2}}$ from carboxylic acid. A general decarboxylation reaction is shown below.

$\text{RCOOH}\to \text{R}-\text{H}+{\text{CO}}_{\text{2}}$

Esters in the presence of base undergo saponification reaction to from sodium salt of carboxylic acid and alcohol.

Claisen condensation takes place between two esters or between an ester and a ketone. In crossed Claisen condensation reaction, a base abstracts an acidic proton from an $\text{α}$ carbon atom of carbonyl compound to form an enolate. This enolate reacts with the carbonyl group of other carbonyl compounds that lead to the formation of $\beta \text{-}$ ketoester.

Interpretation Introduction

(b)

Interpretation:

The synthesis of the given compound from a $\beta \text{-}$ keto ester is to be predicted. The synthesis of the corresponding $\beta \text{-}$ keto ester is to be predicted.

Concept introduction:

The decarboxylation reaction is a type of reaction in which a compound loses ${\text{CO}}_{\text{2}}$ from a carboxylic acid. A general decarboxylation reaction is shown below.

$\text{RCOOH}\to \text{R}-\text{H}+{\text{CO}}_{\text{2}}$

Esters in the presence of base undergo saponification reaction to from sodium salt of carboxylic acid and alcohol.

Claisen condensation takes place between two esters or between an ester and a ketone. In crossed Claisen condensation reaction, a base abstracts an acidic proton from an $\text{α}$ carbon atom of a carbonyl compound to form an enolate. This enolate reacts with the carbonyl group of other carbonyl compounds that lead to the formation of $\beta \text{-}$ ketoester.