Question

Primary alcohols are prepared by the reduction of carboxylic acids. Though lithium aluminium hydride is a strong reducing agent, it is not used in the reaction. This is so because:

Options

• Only used for secondary and tertiary alcohols

• It is an expensive reagent

• Yield is low

• None of these

Answer 1

It is an expensive reagent

Explanation:

Carboxylic acids are reduced to primary alcohols in excellent yields by lithium aluminium hydride, a strong reducing agent.

However, LiAlH₄ is an expensive reagent, and therefore, used for preparing special chemicals only.

Commercially, acids are reduced to alcohols by converting them to esters followed by their reduction using hydrogen in the presence of a catalyst (catalytic hydrogenation).