Question

Preparation of benzamide from benzoyl chloride and ammonia principle

Answer 1

After the removal of hydrochloric acid from the reactants benzoyl chloride and ammonia, the product benzamide obtained.

Answer 2

Below are the steps involved in synthesis of benzamide from benzoyl chloride and ammonia:

1. Initially, benzoic acid is prepared from benzaldehyde
2. Then, using benzaldehyde, benzoyl chloride is prepared
3. Finally benzamide is synthesized using benzoyl chloride in addition with ammonia
4. About 5ml of concentrated ammonia is added with 5ml of water in a clean conical flask.
5. About 2ml of benzoyl chloride is added to this flask and shaken forcefully.
6. This hot shaken mixture is cooled, filtered, washed in cold water.
7. Colorless crystals of benzamide are obtained.

Principle: Cl- explosion occurs because of regeneration of carbonyl group.