Interpretation: In the given intramolecular Diels-Alder reaction, the structural formula of the product has to be predicted.
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
Example:
This mechanism shown that three
Diels-Alder reaction to form bicyclic system:
The Diels-Alder adduct formed in the Diels-Alder reaction can also be a bicyclic system which will be obtained when cylopentadiene is used as the diene as shown here:
In this reaction, the cylopentadiene acts as both diene and dienophile and formed a bicyclic system. When it is heated to
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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Chapter 20 Solutions
Organic Chemistry
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- a-Tetralone undergoes Birch reduction to give an excellent yield of a single product. Predict the structure of the product, and propose a mechanism for its formation.arrow_forwardTreating cyclohexene with HBr in the presence of acetic acid gives bromocyclohexane(85%) and cyclohexyl acetate (15%).Propose a mechanism for the formation of the latter productarrow_forwardTreatment of 3-chloro-2-cyclohexenone with sodium ethoxide in methanol gives 3-ethoxy-2-cyclohexene. Propose a mechanism for this reaction that accounts for the formation of the product.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning