1. Chapter 18 Amines and Amides

2. Preparation of Amides
Amides are prepared by heating a carboxylic acid with
ammonia or an amine (1° or 2°).

3. Amides
In amides, an amino group(–NH2) replaces the –OH group of carboxylic acids.

4. Guide to Naming Amides

5. Common Names of Amides
In the common names of amides, replace the ic acid ending of the corresponding carboxylic acid with amide.

6. IUPAC Names of Amides Write the IUPAC name for 
STEP 1 Identify the corresponding carboxylic acid.
butanoic acid
STEP 2 Replace oic acid with amide.
butanamide
STEP 3 Name a substituent on the N atom using the
prefix N- and the substituent name.
N-methylbutanamide

7. Examples of IUPAC and Common Names
N-Methylethanamide (IUPAC)
N-Methylacetamide (common)
N-Ethylpropanamide (IUPAC)
N-Ethylpropionamide (common)

8. Learning Check
Write the IUPAC name for the following:

9. Solution STEP 1 Identify the corresponding carboxylic acid.
pentanoic acid
STEP 2 Replace oic acid with amide.
pentanamide
STEP 3 Name substituents on the N atom using the
prefix N- and their names N,N-diethylpentanamide

10. Aromatic Amides
The amide of benzene is named benzamide.

11. Learning Check Draw the condensed structural formulas of:
A. pentanamide
B. N-methylbutyramide

12. Solution Draw the condensed structural formulas of: A. pentanamide
B. N-methylbutyramide

13. Classification of Amides
Amides are classified according to the number of carbon atoms bonded to the nitrogen atom.
Primary (1°) amide
Secondary (2°) amide
Tertiary (3°) amide

14. Learning Check Give the common and IUPAC names for the following
amides, and classify them as primary, secondary, or
tertiary.

15. Solution Give the common and IUPAC names for the following
amides, and classify them as primary, secondary, or tertiary.
Butryamide (common)
butanamide (IUPAC)
primary (1°)
N-Ethyl-N-methylacetamide (common)
N-ethyl-N-methylethanamide (IUPAC), tertiary (3°)

16. Some Amides in Health and Medicine
Amides found in health and medicine include the
following:
urea, the end product of protein metabolism
saccharin, an artificial sweetener
barbituarates, such as phenobarbital, Nembutal, and Seconal
acetaminophen, used to reduce fever and pain

17. Some Amides in Health and Medicine (continued)

18. Melting Points of Amides
that are primary and secondary form hydrogen bonds and have high melting points
that are tertiary (no H on N) do not form hydrogen bonds and have lower melting points

19. Solubility of Amides in Water
Primary, secondary, and tertiary amides with 1 to 5 carbon atoms
form hydrogen bonds with
water
are soluble in water