Concept explainers
(a)
Interpretation:
The possible structures of the starting materials of the given Diels-Alder product are to be given.
Concept introduction:
In order to find the starting materials of the given compounds follows the rules are given below.
First, label the double bond carbons as
In order to complete the diene structure, eliminate the double bonds between
In order to complete the dienophile structure, add the double bonds between its carbons.
Also, dienophile is substituted with electron withdrawing groups.
Answer to Problem 15.20P
The possible structures of starting materials of given compound can be as follows.
Explanation of Solution
First designate the double bond carbon atoms as
Figure 1
In order to complete the structure of diene, remove the double bonds present between carbons
Figure 2
Finally, complete the dienophile structure by adding the double bonds between carbons.
Figure 3
Similarly, second possibility on the basis of above mentioned steps will be as follows.
First designate the double bond carbons as
Figure 4
In order to complete the structure of diene, remove the double bonds present between carbons
Figure 5
Finally, complete the dienophile structure by adding the double bonds between carbons
Figure 6
The possible starting materials of the given compound are shown in Figure 3 and Figure 6.
(b)
Interpretation:
The possible structures of the starting materials of the given Diels-Alder product are to be given.
Concept introduction:
First, label the double bond carbons as
In order to complete the diene structure, eliminate the double bonds between
In order to complete the dienophile structure, add the double bonds between its carbons.
Also, dienophile is substituted with electron withdrawing groups.
Answer to Problem 15.20P
The possible structures of starting materials of given compound are shown below.
Explanation of Solution
First designate the double bond carbons as
Figure 7
In order to complete the structure of diene, remove the double bonds present between carbons
Figure 8
Finally, complete the dienophile structure by adding the double bonds between carbon atoms.
Figure 9
The possible starting materials of given compound are shown in Figure 9.
(c)
Interpretation:
The possible structures of the starting materials of the given Diels-Alder product are to be given.
Concept introduction:
First, label the double bond carbons as
In order to complete the diene structure, eliminate the double bonds between
In order to complete the dienophile structure, add the double bonds between its carbons.
Also, dienophile is substituted with electron withdrawing groups.
Answer to Problem 15.20P
The possible structures of starting materials of given compound are as follows.
Explanation of Solution
First designate the double bond carbons as
Figure 10
In order to complete the structure of diene, remove the double bonds present between carbons
Figure 11
Finally, complete the dienophile structure by adding the double bonds between carbons.
Figure 12
The possible starting materials of given compound are shown in Figure 12.
(d)
Interpretation:
The possible structures of the starting materials of the given Diels-Alder product are to be given.
Concept introduction:
First, label the double bond carbons as
In order to complete the diene structure, eliminate the double bonds between
In order to complete the dienophile structure, add the double bonds between its carbons.
Also, dienophile is substituted with electron withdrawing groups.
Answer to Problem 15.20P
The possible structures of starting materials of given compound are as follows.
Explanation of Solution
First designate the double bond carbons as
Figure 13
In order to complete the structure of diene, remove the double bonds present between carbons
Figure 14
Finally, complete the dienophile structure by adding the double bonds between carbons.
Figure 15
The possible starting materials of given compound are shown in 15.
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Chapter 15 Solutions
Organic Chemistry
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