1. Amines Chapter 20

2. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

3. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

4. Examples:
Amines are much more polar, than hydrocarbons, especially in acidic conditions

5. Priority of citation: -COOH > -CHO > -OH > -NH2 > C=C
The atom of N has the trigonal pyramid or trigonal planar geometry (favored by conjugation)

6. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

7. Amines are typical bases due to the lone electron pair at nitrogen

8. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

9. 3. Alkylation of amines

10. More examples of alkylation:
4. Reductive amination
This reaction provides an efficient approach to primary and secondary amines

11. Borch reduction (one-step reductive amination)

12. Borch reduction is also efficient to synthesize tertiary amines

13. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

14. As opposed to alkylation, acylation efficiently produces all types of amides, because amides are weaker nucleophiles, than the starting amines, and do not react further

15. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

16. Because of the steric hindrance, created by the bulky trimethylammonium group,
the reaction proceeds against the Zaitsev’s rule

17. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

19. A standard sequence of protection-deprotection allows to synthesize p-nitroaniline
in a high yield

20. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

22. Examples:

23. The reaction does not yield a product for alkylamines, however,
nitrosation can occur at an aryl substituent

24. Reactions of diazonium salts with loss of nitrogen

25. Reactions of diazonium salts without loss of nitrogen
Diazonium salts also act as weak electrophiles with phenols, and produce a vast variety
of azo-dyes. Many of these dyes are acid-base indicators.

26. Outline
1. Structure, nomenclature and physical properties of amines
2. Acidity and basicity of amines
3. Alkylation of amines
4. Reductive amination
5. Acylation of amines
6. Hoffmann elimination
7. Electrophilic reactions of aniline
8. Reaction of amines with nitrous acid. Diazonium salts
9. Synthesis of amines

27. Gabriel synthesis of primary amines

29. Curtius rearrangement
Example:

30. Hoffmann rearrangement
(an alternative way to produce an isocyanate)