(a)
Interpretation:
Whether the carbocation formed by protonation of isoprene at
Concept introduction:
The delocalization of electrons results in the formation of resonance structure. The curved-arrow notation traces the flow of the electrons in a compound. This notation is used to derive the resonance structure.
Answer to Problem 15.65AP
The carbocation which is formed by protonation of isoprene at
Explanation of Solution
The given structure of isoprene is shown below.
Figure 1
At the time of protonation at carbon
Figure 2
At the time of protonation at carbon
Figure 3
The more stable carbocation is selected on the basis of inductive effect as both carbocation at carbon
Therefore, tertiary carbocation formed at carbon
The carbocation which is formed by protonation of isoprene at
(b)
Interpretation:
The products that are formed by the addition of one equivalent of
Concept introduction:
The delocalization of electrons results in the formation of resonance structure. The curved-arrow notation traces the flow of the electrons in a compound. This notation is used to derive the resonance structure.
Answer to Problem 15.65AP
The products that are formed by the addition of one equivalent of
Explanation of Solution
The given structure of isoprene is shown below.
Figure 1
An isoprene always forms the
Figure 4
Therefore, the products formed by the conjugated diene, isoprene are
The products,
(c)
Interpretation:
The products that are formed the addition of one equivalent of
Concept introduction:
The delocalization of electrons results in the formation of resonance structure. The curved-arrow notation traces the flow of the electrons in a compound. This notation is used to derive the resonance structure.
Answer to Problem 15.65AP
The products that are formed the addition of one equivalent of
Explanation of Solution
In case of
The protonation of
Figure 5
The reaction of
The products,
(d)
Interpretation:
The products which are formed in part (b) and (c) whether kinetically controlled products or
Concept introduction:
In the given conditions of the reaction, if the products of any reaction do not attain the equilibrium then the reaction is known as kinetically controlled reaction.
In the given conditions of the reaction, if the products of any reaction attain the equilibrium then the reaction is known as thermodynamically controlled reaction.
Answer to Problem 15.65AP
In part (b),
In part (c),
Explanation of Solution
The kinetically controlled products are formed much faster than thermodynamically controlled products. So, the
In part (b), the reaction of the given isoprene with
Figure 6
In part (c), the slowest addition is the
Therefore,
Figure 7
In part (b),
In part (c),
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Chapter 15 Solutions
Organic Chemistry Study Guide and Solutions
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