Chapter 20, Problem 20.34P

Interpretation Introduction

Interpretation:

How the carbon skeleton of the given triene must be coiled to give the given product has to be shown.

Concept Introduction:

Diels-Alder reaction:

It is the reaction of conjugated dienes with double or triple bonded compounds which are known as “dienophiles”. The reaction is a $4+2$ cycloaddition reaction that results in the formation of a six membered cyclic product which is known as “adduct”.

Example:

This mechanism shown that three $\text{π}$-bonds are broken to form two new $\text{σ}$ -bonds and a new $\text{π}$-bond.

Intramolecular reaction:

In the word “Intramolecular”- “Intra”- means “within” or “in”. So an intramolecular reaction means the reaction is taking place within one molecule itself without the involvement of any other molecules.