Catalytic hydrogenation of ketones with lithium aluminium hydride gives

Secondary alcohols

The correct answer is Option (2) → Secondary alcohols

Core Concept

LiAlH₄ is a strong reducing agent that converts ketones into secondary alcohols.

Reaction

R–CO–R' → (LiAlH₄ / H₂O) → R–CHOH–R'

Explanation of Each Option

1. Primary alcohols are formed when aldehydes are reduced, not ketones. Since ketones contain two alkyl groups attached to the carbonyl carbon, their reduction does not produce primary alcohols.

2. Secondary alcohols are formed when ketones are reduced because the carbonyl carbon already has two alkyl groups attached. Reduction converts the C=O group into C–OH while retaining the two alkyl groups, giving a secondary alcohol.

3. Tertiary alcohols are not formed by simple reduction of ketones. They are usually formed through reactions like Grignard addition to ketones followed by hydrolysis.

4. Esters are not produced during reduction; instead, reduction leads to alcohol formation by addition of hydride ion to the carbonyl group.