Which of the following is a strong reducing agent used to reduce aldehydes, ketones, esters, carboxylic acid chlorides, carboxylic acids and even carboxylate salts to alcohols?

Correct option is B

The correct answer is (b) Lithium aluminium hydride.

• Lithium aluminium hydride (LiAlH₄) is a very strong reducing agent in organic chemistry.

• It can reduce a wide range of carbonyl and carboxylic derivatives to alcohols, including:

  • Aldehydes → primary alcohols

  • Ketones → secondary alcohols

  • Esters → primary alcohols

  • Acid chlorides → primary alcohols

  • Carboxylic acids → primary alcohols

  • Even carboxylate salts → alcohols (under suitable conditions)

• LiAlH₄ is stronger than NaBH₄ (sodium borohydride).

• It reacts violently with water, so reactions are carried out in dry ether solvents (like diethyl ether).

• Final work-up is done using water or dilute acid to liberate the alcohol.

• Sodium borohydride (NaBH₄) can reduce only aldehydes and ketones, not carboxylic acids or esters.

• Calcium hydride (CaH₂) is mainly used as a drying agent, not as a reducing agent.

• Titanium hydride and bismuth hydride are not commonly used as organic reducing agents.

• LiAlH₄ is extensively used in pharmaceutical and fine chemical synthesis.