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A : Esters on reduction with LiAlH(4) fo...

A : Esters on reduction with `LiAlH_(4)` forms alcohols.
R : Esters having at least two `alpha`-Hydrogen atoms undergo Claisen condensation.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).

C

If Assertion is true statement but Reason is false, then mark (3).

D

If both Assertion and Reason are false statements, then mark (4).

Text Solution

AI Generated Solution

The correct Answer is:
To analyze the question, we have two statements: **Assertion (A):** Esters on reduction with LiAlH₄ form alcohols. **Reason (R):** Esters having at least two alpha-hydrogen atoms undergo Claisen condensation. Let's evaluate both statements step by step. ### Step 1: Understanding the Assertion - **Assertion (A):** Esters on reduction with LiAlH₄ form alcohols. - Lithium aluminum hydride (LiAlH₄) is a strong reducing agent. - When an ester (RCOOR') is treated with LiAlH₄, it undergoes reduction. - The carbonyl carbon (C=O) of the ester is attacked by the hydride ion (H⁻) from LiAlH₄. - This leads to the formation of an intermediate alkoxide (RCO⁻R'). - Upon hydrolysis (reaction with water), this alkoxide is converted into a primary alcohol (RCH₂OH). **Conclusion for Assertion:** The assertion is correct because esters do indeed form alcohols when reduced with LiAlH₄. ### Step 2: Understanding the Reason - **Reason (R):** Esters having at least two alpha-hydrogen atoms 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. - For Claisen condensation to occur, at least one of the reactants must have alpha-hydrogens that can be deprotonated to form an enolate ion. - The presence of two alpha-hydrogens allows for the formation of the enolate ion, which can then attack the carbonyl carbon of another ester. - However, it is important to note that at least one alpha-hydrogen is sufficient for the reaction to occur, not necessarily two. **Conclusion for Reason:** The reason is incorrect because while having two alpha-hydrogens allows for Claisen condensation, it is not a requirement; only one alpha-hydrogen is necessary. ### Final Conclusion - The assertion is correct, but the reason is incorrect. Therefore, the correct answer is that the assertion is true, but the reason is false. ### Summary - **Assertion (A)** is true: Esters reduce to alcohols with LiAlH₄. - **Reason (R)** is false: Only one alpha-hydrogen is needed for Claisen condensation.
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