Interpretation:
The observation that 1, 3-cyclopentadiene is very reactive in Diels-Alder reaction, but 1, 3-cyclohexadiene is less reactive and 1, 3-cycloheptadiene is inert is to be explained.
Concept introduction:
In Diels-Alder reaction, a dienophile reacts with a diene to yield a cyclic adduct. The reaction takes place through 1, 4 addition of the dienophile into the diene through a cyclic transition state. These reactions occur rapidly with dienophiles having electron withdrawing substituent groups in conjugation with the double bond and if the diene adapts a s-cis conformation during the reaction.
To explain:
The observation that 1, 3-cyclopentadiene is very reactive in Diels-Alder reaction, but 1, 3-cyclohexadiene is less reactive and 1, 3-cycloheptadiene is inert.
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Chapter 14 Solutions
Organic Chemistry
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning