Interpretation:
The observation that photolysis of cis-cyclobutene yields cis-cyclododecaen-7-yne but photolysis of trans-cyclobutene yields trans-cyclododecaen-7-yne is to be explained by identifying the type and stereochemistry of the pericyclic reaction involved.
Concept introduction:
An electrocyclic reaction involves the cyclization of a conjugated acyclic system. These reactions are reversible and are highly stereospecific.
In elecrocyclic reactions involving even number of electron pairs, a thermal reaction occurs in conrotatory manner and a photochemical reaction occurs in disrotatory manner.
In elecrocyclic reactions involving odd number of electron pairs, a thermal reaction occurs in disrotatory manner and a photochemical reaction occurs in conrotatory manner.
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Organic Chemistry
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning