19.2.3—Hydrolysis of nitriles with dil. acid or dil.
- Syllabus
- 9701–2028–2029
- Objective
- 19.2.3
- Level
- AS
Nitrile hydrolysis converts –C≡N into a carboxylic acid after acidification
Dilute acid or dilute alkali hydrolyses a nitrile through amide/carboxylate stages. Acid work-up gives the carboxylic acid; alkaline conditions initially give a carboxylate salt.
The nitrile carbon becomes the carboxyl carbon, so the chain is retained after the earlier KCN extension. State whether the reaction mixture is acidic or alkaline at the final step.
CH₃CH₂CN + 2H₂O → CH₃CH₂COOH + NH₃ under acid hydrolysis (simplified overall equation). In alkali, propanoate forms first and is then acidified.
Do not lose the nitrile carbon or report a carboxylate as the acid before acidification.
ConceptA-Level CAIE Chemistry AS