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 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.
d)
Interpretation: The diene and dienophile from the given compounds 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.
e)
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.
f)
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.
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Chapter 8 Solutions
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