Chapter 11.16, Problem 24P

Interpretation Introduction

Interpretation

The structure for the derivative of divinylcyclopropane including its stereochemistry is to be deduced.

Concept introduction:

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Reactions of dienes that proceed in a single step by way of cyclic transition state are called pericyclic reactions.

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Compounds having $\text{1,5-diene}$ unit undergo an intramolecular reaction that converts it into a different $\text{1,5-diene}$ unit. This is known as Cope rearrangement.

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Cope rearrangement is a type of pericyclic reaction in which one $\text{1,5-diene}$ unit is converted to another through a cyclic transition state.

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The reactant molecule must have two isolated double bonds at $\text{C-1 and C-5}$ carbon atoms.

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The reaction must pass through a cyclic transition state to produce two cis double bonds in the ring.

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The product of the Cope rearrangement has double bonds at $\text{C-1 and C-4}$ carbon atoms.