CHAPTER 6

1. CHAPTER 6 AMINESANDAMIDES

2. Primary (1°) - one C attached to N Secondary (2°) - two C attached to N Tertiary (3°) - three C attached to N

3. Naming Amines • Primary Amines 1. Determine the longest carbon chain containing the NH2 group 2. Drop the (e) from the alkane name and add amine to the end 3. Indicate the position of the NH2 group

4. Methanamine 2-Propanamine Cyclopentamine

5. Name:

7. Secondary and Tertiary Amines Same attachments to nitrogen use di and tri

8. Secondary and Tertiary Amines Different attachments on the Nitrogen 1. Root name is based on the longest carbon chain Other attachments are based on the alkyl name N before attachment name indicates it is on the nitrogen

9. Longest carbon chain? 2 carbons=ethanamine Other attachments on nitrogen? 2 methyls N,N-dimethyl ethanamine Longest carbon chain? 3 carbons=propanamine Other attachments on nitrogen? methyl N-methyl propanamine • Draw N-ethyl N-methyl butanamine

10. Physical Properties • Like ammonia, low-molecular-weight amines have very sharp, penetrating odors. • Trimethylamine, for example, is the pungent principle in the smell of rotting fish. • Two other particularly pungent amines are 1,4-butanediamine (putrescine) and 1,5-pentanediamine (cadaverine).

11. Physical Properties of Amines • The N-H bond is not quite as polar as the O-H bond. • Primary and secondary amines can form hydrogen bonds between molecules.

12. Physical Properties • The N-H bond is not as polar as the O-H bond so amines have lower boiling points than alcohols of similar molecular weight

13. Physical Properties, cont. • Amines can hydrogen bond with water, making smaller amine molecules water soluble.

14. Basicity of Amines • Like ammonia, amines are weak bases, and aqueous solutions of amines are basic. • The acid-base reaction between an amine and water involves transfer of a proton from water to the amine.

15. Amine Neurotransmitters • Neurotransmitter – a chemical bridge between nerve cells.

16. Important Amine Neurotransmitters • Acetylcholine • Dopamine – synthesized from the amino acid tyrosine.

17. Norepinephrine – synthesized from dopamine, may be associated with mental illness. • Serotonin – synthesized from the amino acid tryptophan, may be associated with mental illness.

19. Epinephrine (adrenaline) – more important as a hormone than a neurotransmitter. Fight-or-flight hormone, released in response to pain, anger, or fear, increases blood glucose level for energy.

20. Amphetamines – nervous system stimulants, similar in structure to epinephrine.

21. Alkaloids – a class of nitrogen–containing organic compounds obtained from plants. • Examples include: • Nicotine – found in tobacco • Caffeine – found in coffee • and cola drinks • Quinine – used to treat malaria

22. Opium – used to make codeine (in cough medicines), morphine (pain killer) and heroin.

23. REACTIONS Carboxylic Acid + Amine Amide

25. Naming Amides O methanamide (IUPAC) HC–NH2 O propanamide (IUPAC) CH3CH2C–NH2

26. Naming Amides with N-Groups O  CH3C–NHCH3N-methylethanamide (IUPAC) O  CH3CH2C–N(CH3)2 N,N-dimethylpropanamide

27. Name the following amides: O  A. CH3CH2CH2C–NH2 O  B. CH3C–N(CH2CH3)2

28. Structure of 3-methyl pentamide Structure of N-methyl pentamide

29. Hydrolysis of Amides Hydrolysis – the reverse of amide formation, the amide linkage is cleaved using water to produce a carboxylic acid and an amine.

31. Amide linkage

32. Polyamides • Reaction of dicarboxylic acid with diamine • Nylon, Kevlar, amino acids