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Assertion: Esters which contain alpha-hy...

Assertion: Esters which contain `alpha-`hydrogens undergo Claisen condensation.
Reason : `LiAIH_(4)` reduction of esters gives acids

A

a. If both assertion and reason are true and reason is the correct explanation of assertion

B

b. If both assertion and reason are true but reason is not the correct explanation of assertion

C

c. If assertion is true but reason is false

D

d. If both assertion and reason are false.

Text Solution

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The correct Answer is:
To solve the question, we will analyze the assertion and the reason provided separately. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that "Esters which contain alpha-hydrogens undergo Claisen condensation." - Claisen condensation is a reaction between two esters or an ester and a carbonyl compound in the presence of a strong base, resulting in the formation of a β-keto ester or a β-diketone. - For Claisen condensation to occur, the ester must have at least one alpha-hydrogen. This is because the alpha-hydrogen is necessary for the formation of an enolate ion, which acts as a nucleophile in the reaction. 2. **Understanding the Reason**: - The reason states that "LiAlH₄ reduction of esters gives acids." - Lithium aluminum hydride (LiAlH₄) is a strong reducing agent that can reduce esters to primary alcohols, not acids. The reduction of esters by LiAlH₄ results in the formation of alcohols and not acids. Therefore, this statement is incorrect. 3. **Conclusion**: - The assertion is true because esters with alpha-hydrogens do undergo Claisen condensation. - The reason is false because the reduction of esters by LiAlH₄ yields alcohols, not acids. - Based on this analysis, the correct answer is that the assertion is true, but the reason is false. ### Final Answer: Assertion is true, but the reason is false. Therefore, the correct option is **C**. ---
To solve the question, we will analyze the assertion and the reason provided separately. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that "Esters which contain alpha-hydrogens undergo Claisen condensation." - Claisen condensation is a reaction between two esters or an ester and a carbonyl compound in the presence of a strong base, resulting in the formation of a β-keto ester or a β-diketone. - For Claisen condensation to occur, the ester must have at least one alpha-hydrogen. This is because the alpha-hydrogen is necessary for the formation of an enolate ion, which acts as a nucleophile in the reaction. ...
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