15.17 Chemical Properties of Amides: Hydrolysis

Learning Objective

  1. Identify the typical reaction that amides undergo.

Generally, amides resist hydrolysis in plain water, even after prolonged heating. In the presence of added acid or base, however, hydrolysis proceeds at a moderate rate. In living cells, amide hydrolysis is catalyzed by enzymes. Amide hydrolysis is illustrated in the following example:

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Note

Hydrolysis of an amide in acid solution actually gives a carboxylic acid and the salt of ammonia or an amine (the ammonia or amine initially formed is neutralized by the acid). Basic hydrolysis gives a salt of the carboxylic acid and ammonia or an amine.

Example 17

Write the equation for the hydrolysis of each compound.

  1. butyramide
  2. benzamide

Solution

  1. The hydrolysis of a simple amide produces an organic acid and ammonia. Butyramide thus yields butyric acid and ammonia.

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  2. The hydrolysis of an amide produces an organic acid and ammonia. Benzamide thus yields benzoic acid and ammonia.

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Skill-Building Exercise

Write the equation for the hydrolysis of each compound.

  1. propionamide (propanamide)

  2. hexanamide

Concept Review Exercises

  1. What are the products of the hydrolysis of an amide?

  2. When the amide CH3CH2CH2CH2CONH2 is hydrolyzed in an NaOH solution, the products are CH3CH2CH2CH2COO−Na+ and NH3. What products are obtained when CH3CH2CH2CH2CONH2 is hydrolyzed in an hydrochloric acid solution?

Key Takeaway

  • The hydrolysis of an amide produces a carboxylic acid and ammonia or an amine.

Exercises

  1. Complete each equation.

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  2. Complete each equation.

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