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 π -bonds are broken to form two new σ -bonds and a new 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.

Question

Write a general rule that can be used to predict the major product of a Diels–Alder reaction between an alkene with an electron-withdrawing substituent and a diene with a substituent that can donate electrons by resonance depending on the location of the substituent on the diene.

Answer 1

Question

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 π-bonds are broken to form two new σ -bonds and a new 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.

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Write a general rule that can be used to predict the major product of a Diels–Alder reaction between an alkene with an electron-withdrawing substituent and a diene with a substituent that can donate electrons by resonance depending on the location of the substituent on the diene.

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