(a)
Interpretation: The diene and dienophile from the given compounds has to be predicted.
Concept Introduction:
Diels-Alder reaction:
A conjugated diene reacts with a compound containing a carbon-carbon double bond. It is a cycloaddition reaction, where two reactants form a cyclic product.
Conformation of Diene:
S-Cis Conformer: The double bonds are cis about the single bond (s stands for single), in an s-cis conformer.
S-trans Conformer: The double bonds are trans- about the single bond (s stands for single) in an s-trans conformer.
Condition for Diels-Alder reaction:
The conjugate diene must be in an s-cis conformation because when it is in an S-trans conformation, C-1 and C-4 are too far apart to react with the dienophile in a concerted reaction.
(b)
Interpretation: The diene and dienophile from the given compounds has to be predicted.
Concept Introduction:
Diels-Alder reaction:
A conjugated diene reacts with a compound containing a carbon-carbon double bond. It is a cycloaddition reaction, where two reactants form a cyclic product.
Conformation of Diene:
S-Cis Conformer: The double bonds are cis about the single bond (s stands for single), in an s-cis conformer.
S-trans Conformer: The double bonds are trans- about the single bond (s stands for single) in an s-trans conformer.
Condition for Diels-Alder reaction:
The conjugate diene must be in an s-cis conformation because when it is in an S-trans conformation, C-1 and C-4 are too far apart to react with the dienophile in a concerted reaction.
(c)
Interpretation: The diene and dienophile from the given compounds have to be predicted.
Concept Introduction:
Diels-Alder reaction:
A conjugated diene reacts with a compound containing a carbon-carbon double bond. It is a cycloaddition reaction, where two reactants form a cyclic product.
Conformation of Diene:
S-Cis Conformer: The double bonds are cis about the single bond (s stands for single), in an s-cis conformer.
S-trans Conformer: The double bonds are trans- about the single bond (s stands for single) in an s-trans conformer.
Condition for Diels-Alder reaction:
The conjugate diene must be in an s-cis conformation because when it is in an S-trans conformation, C-1 and C-4 are too far apart to react with the dienophile in a concerted reaction.
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Organic Chemistry (8th Edition)
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning