Chapter 22, Problem 22.28P

Interpretation Introduction

(a)

Interpretation:

An explanation as to why compound A when treated with one equivalent of $\text{NaOEt}$ followed by acidification is completely converted to compound B is to be stated.

Concept introduction:

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

The intramolecular Claisen condensation in which the product is a five or six member ring is known as Dieckmann condensation.

Interpretation Introduction

(b)

Interpretation:

The curved arrow mechanism for the given conversion is to be stated.

Concept introduction:

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

The intramolecular Claisen condensation in which the product is a five or six member ring is known as Dieckmann condensation.

Interpretation Introduction

(c)

Interpretation:

The structure of the only product formed when diethyl $\text{α-}$ methyladipate reacts in the Dieckmann condensation is to be shown.

Concept introduction:

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

The intramolecular Claisen condensation in which the product is a five or six member ring is known as Dieckmann condensation.