Question

The reagent used for the conversion of carboxylic acids to primary alcohols is

• A. PCC
• B. LiAlH\(_4\) / H\(_2\)O
• C. NaNO\(_2\) / HCl
• D. Pd / H\(_2\)
• E. Pt / H\(_2\)

Hint:

LiAlHâ‚„ is a very powerful reducing agent that can reduce carboxylic acids, esters, aldehydes, and ketones to alcohols.

Answer 1

The Correct Option is B

To reduce carboxylic acids to primary alcohols, a strong reducing agent is required. - Option (A): PCC (Pyridinium chlorochromate) is a selective oxidizing agent, but it is used for the oxidation of alcohols to aldehydes or ketones. It is not a reducing agent and cannot reduce carboxylic acids to alcohols. - Option (B): LiAlH\(_4\) (Lithium aluminum hydride) is a strong reducing agent that can reduce carboxylic acids to primary alcohols. The addition of water (Hâ‚‚O) helps in the hydrolysis process to convert the intermediate into the alcohol. - Option (C): NaNO\(_2\) (Sodium nitrite) and HCl are involved in the diazotization reaction for aromatic compounds and do not reduce carboxylic acids to alcohols. - Option (D): Pd / H\(_2\) (Palladium on hydrogen) is used for hydrogenation reactions but is typically used for the reduction of alkenes to alkanes, not for reducing carboxylic acids. Thus, the correct answer is (B) LiAlHâ‚„ / Hâ‚‚O, as it is the correct reagent for reducing carboxylic acids to primary alcohols.