The major product formed in the following reaction is: (i) $\xrightarrow[\text { EtOH }]{\mathrm{LiBH}_{4}}$ major product (ii) $\mathrm{H}_{3} \mathrm{O}^{+}$

JEE Main · 2023 · 08 Apr 2023 · Shift 1 · Aldehydes Ketones and Carboxylic Acids

The major product formed in the following reaction is:

(i)

LiBH_{4} EtOH

major product
(ii)

H_{3} O^{+}

(A)(see structure)
(B)(see structure)
(C)(see structure)
✓ Correct
(D)(see structure)

Answer: (C)

Solution

LiB H_{4}

is a mild hydride reagent: it reduces esters to primary alcohols but leaves carboxylic acids untouched, because the carboxylate formed on deprotonation resists further hydride attack. In this substrate the ester arm

- C H_{2} C O_{2} Et

is reduced to the primary alcohol

- C H_{2} C H_{2} OH

, while the carboxylic acid arm

- C H_{2} C H_{2} C O_{2} H

survives both the reduction and the acidic workup unchanged. The major product therefore retains its carboxylic acid group and carries a new primary alcohol where the ester once stood.

JEE Main · 2023 · 08 Apr 2023 · Shift 1 · Single correct option

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JEE Main · 2023 · 08 Apr 2023 · Shift 1 · Aldehydes Ketones and Carboxylic Acids

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