a)
Interpretation:
The product of the Wolff-Kishner reduction reaction shown is to be given. The electron-pushing mechanism, beginning from the hydrazone intermediate is to be provided.
Concept introduction:
In Wolff-Kishner reduction
To give:
The product of the Wolff-Kishner reduction reaction shown.
To provide:
The electron-pushing mechanism, beginning from the hydrazone intermediate.
Answer to Problem 38MP
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism for the formation of the alkane, beginning from the hydrazone intermediate, is given below.
Explanation of Solution
The hydroxide ion from KOH abstracts a weakly acidic H from –NH2 of the hydrazone of isopropyl phenyl ketone to yield a carbanion which picks up a proton to yield a neutral intermediate. Deprotonation of the remaining hydrogen on N by the hydroxide ion occurs with the eliminartion of nitrogen to yield another carbanion which is protonated to give the alkane, ethyl benzene, as the product.
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism, beginning from the hydrazone intermediate is given below.
b)
Interpretation:
The product of the Wolff-Kishner reduction reaction shown is to be given. The electron-pushing mechanism, beginning from the hydrazone intermediate is to be provided.
Concept introduction:
In Wolff-Kishner reduction aldehydes and ketones react with hydrazine in the presence of a base to yield alkanes. First a hydrazone is formed which is then converted into an alkane.
To give:
The product of the Wolff-Kishner reduction reaction shown.
To provide:
The electron-pushing mechanism the formation of the alkane beginning from the hydrazone intermediate.
Answer to Problem 38MP
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism the formation of the alkane, beginning from the hydrazone intermediate, is given below.
Explanation of Solution
The hydroxide ion from KOH abstracts a weakly acidic H from –NH2 of the hydrazone of diethyl ketone to yield a carbanion which picks up a proton to yield a neutral intermediate. Deprotonation of the remaining hydrogen on N by the hydroxide ion occurs with the eliminartion of nitrogen to yield another carbanion which is protonated to give the alkane, n-pentane, as the product.
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism, beginning from the hydrazone intermediate is given below.
c)
Interpretation:
The product of the Wolff-Kishner reduction reaction shown is to be given. The electron-pushing mechanism, beginning from the hydrazone intermediate is to be provided.
Concept introduction:
In Wolff-Kishner reduction aldehydes and ketones react with hydrazine in the presence of a base to yield alkanes. First a hydrazone is formed which is then converted into an alkane.
To give:
The product of the Wolff-Kishner reduction reaction shown.
To provide:
The electron-pushing mechanism the formation of the alkane beginning from the hydrazone intermediate.
Answer to Problem 38MP
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism the formation of the alkane, beginning from the hydrazone intermediate, is given below.
Explanation of Solution
The hydroxide ion from KOH abstracts a weakly acidic H from –NH2 of the hydrazone of the ketone to yield a carbanion which picks up a proton to yield a neutral intermediate. Deprotonation of the remaining hydrogen on N by the hydroxide ion occurs with the eliminartion of nitrogen to yield another carbanion which is protonated to give the alkane as the product.
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism, beginning from the hydrazone intermediate is given below.
d)
Interpretation:
The product of the Wolff-Kishner reduction reaction shown is to be given. The electron-pushing mechanism, beginning from the hydrazone intermediate is to be provided.
Concept introduction:
In Wolff-Kishner reduction aldehydes and ketones react with hydrazine in the presence of a base to yield alkanes. First a hydrazone is formed which is then converted into an alkane.
To give:
The product of the Wolff-Kishner reduction reaction shown.
To provide:
The electron-pushing mechanism, beginning from the hydrazone intermediate.
Answer to Problem 38MP
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism for the formation of the alkane beginning from the hydrazone intermediate, is given below.
Explanation of Solution
The hydroxide ion from KOH abstracts a weakly acidic H from –NH2 of the hydrazone of ketone to yield a carbanion which picks up a proton to yield a neutral intermediate. Deprotonation of the remaining hydrogen on N by the hydroxide ion occurs with the eliminartion of nitrogen to yield another carbanion which is protonated to give the alkane as the product.
The product of the Wolff-Kishner reduction reaction shown is
The electron-pushing mechanism for the formation of the alkane beginning from the hydrazone intermediate, is given below.
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Chapter 19 Solutions
Organic Chemistry
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningEBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENT