Concept explainers
a)
Interpretation:
The dehydration product formed in the addition reaction of butanal along with the mechanism of its formation is to be predicted.
Concept introduction:
The β- hydroxyl aldehyde or ketone obtained loses a molecule of water upon heating to give an α, β- unsaturated aldehyde or ketone.
To predict:
The dehydration product formed in the addition reaction of butanal along with the mechanism of its formation.
Answer to Problem 28MP
The dehydration product formed in the addition reaction of butanal is 2-ethyl-2-hexenal.
The mechanism of its formation is
Explanation of Solution
In the first step the base picks up an acidic proton from the diketone to produce the enolate anion. In the next step the nucleophilic enolate anion attacks the electrophilic carbon of the other carbonyl group in the same molecule to give an alkoxide. In the next step the alkoxide intermediate is protonated to yield the β- hydroxyl aldehyde. Removal of a proton by the base from the hydroxy aldehyde leads to the formation of α, β- unsaturated aldehyde.
The dehydration product formed in the addition reaction of butanal is 2-ethyl-2-hexenal.
The mechanism of its formation is
b)
Interpretation:
The dehydration product formed in the addition reaction given along with the mechanism of its formation is to be predicted.
Concept introduction:
Aldehydes and ketones that have α- hydrogen atom undergo aldol condensation to yield a β- hydroxyl aldehyde or ketone as the product. The reaction occurs in three steps i) Abstraction of α- hydrogen by a base to yield an enolate anion ii) Attack of the anion on the carbonyl carbon of another molecule iii) Protonation of the alkoxide intermediate.
The β- hydroxyl aldehyde or ketone obtained on heating loses a water molecule to yield an α, β- unsaturated aldehyde or ketone.
To identify:
The dehydration product formed in the addition reaction of cyclobutanone along with the mechanism of its formation.
Answer to Problem 28MP
The dehydration product formed in the addition reaction of cyclobutanone is
The mechanism of its formation is
Explanation of Solution
In the first step the base picks up a proton from the α-carbon of one cyclobutanone molecule to produce the enolate anion. In the next step the nucleophilic enolate anion attacks the electrophilic carbonyl carbon of another cyclobutanoe molecule to give an alkoxide. In the next step the alkoxide intermediate is protonated to yield a β- hydroxyketone. In the final step the base picks up a proton from the hydroxyl group that leads to the formation of α, β- unsaturated ketone.
The dehydration product formed in the addition reaction of cyclobutanone is
The mechanism of its formation is
c)
Interpretation:
The dehydration product formed in the addition reaction given along with the mechanism of its formation is to be predicted.
Concept introduction:
The reaction given is a mixed aldol reaction. Aldehydes and ketones that have α- hydrogen atom undergo aldol condensation to yield a β- hydroxyl aldehyde or ketone as the product. The reaction occurs in three steps i) Abstraction of α- hydrogen by a base to yield an enolate anion ii) Attack of the anion on the carbonyl carbon of another molecule iii) Protonation of the alkoxide intermediate.
The β- hydroxyl aldehyde or ketone loses a molecule of water when heated in the presence of a base to yield α, β- unsaturated aldehyde or ketone.
To identify:
The dehydration product formed in the addition reaction given along with the mechanism of its formation.
Answer to Problem 28MP
The dehydration product formed in the addition reaction given is
The mechanism of its formation is
Explanation of Solution
In the first step the base picks up a proton from the α-carbon of acetaldehyde as it has α- hydrogen atoms to produce the enolate anion. In the next step the nucleophilic enolate anion attacks the electrophilic carbonyl carbon of benzaldehyde to give an alkoxide. In the next step the alkoxide intermediate is protonated to yield a β- hydroxyaldehyde. In the final step the base picks up a proton from the hydroxyl group that leads to the formation of α, β- unsaturated aldehyde.
The dehydration product formed in the addition reaction given is
The mechanism of its formation is
d)
Interpretation:
The product formed in the addition reaction given along with the mechanism of its formation is to be predicted.
Concept introduction:
In intramolecular aldol reactions dicarbonyl compounds such as diketones react with a base to yield a cyclic enone as the products. The reaction occurs in four steps i) Abstraction of α-hydrogen by a base to yield an enolate anion ii) Attack of the anion on the carbonyl carbon in another molecule iii) Protonation of the alkoxide intermediate. iv) Loss of water from the keto alcohol upon heating.
To identify:
The product formed in the addition reaction given along with the mechanism of its formation.
Answer to Problem 28MP
The product formed in the addition reaction given is
The mechanism of its formation is
Explanation of Solution
In the first step the base picks up an acidic proton from the diketone to produce the enolate anion. In the next step the nucleophilic enolate anion attacks the electrophilic carbon of the other carbonyl group in the same molecule to give an alkoxide. In the next step the alkoxide intermediate is protonated to yield a hydroxyl ketone. In the final step the base picks up a proton from the hydroxyl group that leads to the formation of α, β- unsaturated aldehyde.
The product formed in the addition reaction given is
The mechanism of its formation is
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Chapter 23 Solutions
EBK ORGANIC CHEMISTRY
- Hi!! Please provide a solution that is handwritten. Ensure all figures, reaction mechanisms (with arrows and lone pairs please!!), and structures are clearly drawn to illustrate the synthesis of the product as per the standards of a third year organic chemistry course. ****the solution must include all steps, mechanisms, and intermediate structures as required. Please hand-draw the mechanisms and structures to support your explanation. Don’t give me AI-generated diagrams or text-based explanations, no wordy explanations on how to draw the structures I need help with the exact mechanism hand drawn by you!!! I am reposting this—ensure all parts of the question are straightforward and clear or please let another expert handle it thanks!!arrow_forwardHi!! Please provide a solution that is handwritten. Ensure all figures, reaction mechanisms (with arrows and lone pairs please!!), and structures are clearly drawn to illustrate the synthesis of the product as per the standards of a third year organic chemistry course. ****the solution must include all steps, mechanisms, and intermediate structures as required. Please hand-draw the mechanisms and structures to support your explanation. Don’t give me AI-generated diagrams or text-based explanations, no wordy explanations on how to draw the structures I need help with the exact mechanism hand drawn by you!!! I am reposting this—ensure all parts of the question are straightforward and clear or please let another expert handle it thanks!!arrow_forward. (11pts total) Consider the arrows pointing at three different carbon-carbon bonds in the molecule depicted below. Bond B 2°C. +2°C. < cleavage Bond A • CH3 + 26. t cleavage 2°C• +3°C• Bond C Cleavage CH3 ZC '2°C. 26. E Strongest 3°C. 2C. Gund Largest BDE weakest bond In that molecule a. (2pts) Which bond between A-C is weakest? Which is strongest? Place answers in appropriate boxes. Weakest C bond Produces A Weakest Bond Most Strongest Bond Stable radical Strongest Gund produces least stable radicals b. (4pts) Consider the relative stability of all cleavage products that form when bonds A, B, AND C are homolytically cleaved/broken. Hint: cleavage products of bonds A, B, and C are all carbon radicals. i. Which ONE cleavage product is the most stable? A condensed or bond line representation is fine. 人 8°C. formed in bound C cleavage ii. Which ONE cleavage product is the least stable? A condensed or bond line representation is fine. methyl radical •CH3 formed in bund A Cleavagearrow_forward
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Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning