Amines And Amides

Carboxylic Acids Esters, Amines and Amides Amines Reactions of Amines Amides Reactions of Amides

1

Amines • Organic compounds of nitrogen N • Classified as primary, secondary, tertiary CH3 CH3   CH3—NH2 CH3—NH CH3—N — CH3 1°

2°

3°

2

Naming Amines IUPAC aminoalkane CH3CH2NH2 aminoethane (ethylamine)

Common alkylamine CH3—NH —CH3 N-methylaminomethane NH (dimethylamine) 2

NH CH3

NH2 | CH3CHCH3 2-aminopropane (isopropylamine)

Aniline

N-methylaniline 3

Learning Check AM1 Give the common name and classify: A. CH3NHCH2CH3 CH3 | B. CH3CH2NCH3

4

Solution AM1 A. CH3NHCH2CH3 ethylmethylamine, 2°

•

CH3 | CH3CH2NCH3 ethyldimethylamine, 3° 5

Reactions of Amines • Act as weak bases in water CH3NH2 + H2O CH3NH3+ + OH– methylammonium hydroxide • Neutralization with acid gives ammonium salt CH3NH2 + HCl CH3NH3+ Cl– methylammonium chloride 6

Alkaloids • Physiologically active nitrogen-containing compounds • Obtained from plants • Used as anesthetics, antidepressants, and stimulants • Many are addictive

7

Nicotine

CH3 N

Nicotine, leaves of tobacco plant 8

Caffeine O CH3 O

CH3 N

N N

N

CH3 Caffeine, coffee beans and tea

9

Procaine CH3CH2

O N

CH2CH2 O C

NH2

CH3CH2 Procaine (novocaine), painkiller

10

Leaning Check AM2 Write a structural formula for C.

2-aminopentane

B.

1,3-diaminocyclohexane

11

Solution AM2 A.

B.

1-aminopentane CH3CH2CH2CH2CH2-NH2 1,3-diaminocyclohexane NH2

NH2

12

Amides Derivatives of carboxylic acids where an amino (-NH2) group replaces the –OH group. O O ||

CH3 — C—OH carboxylic acid acetic acid

||

CH3 — C—NH2 amide acetamide 13

Naming Amides Alkanamide O || HC–NH2

from acid name methanamide (IUPAC) formamide (common)

O || CH3CH2C–NH2

propanamide (IUPAC) propionamide(common) 14

Naming Amides with N-Groups O || CH3C–NHCH3

N-methylethanamide (IUPAC) N-methylacetamide (common)

O || CH3CH2C–N(CH3)2 N,N-dimethylpropanamide N,N-dimethylpropionamide

15

Aromatic Amides O

O

C NH2

C NHCH 3

Benzamide

N -methylbenzamide 16

Learning Check AM3 Name the following amides: O || A. CH3CH2CH2C–NH2 O || B.

CH3C–N(CH2CH3)2 17

Solution AM3 O ||

A.

CH3CH2CH2C–NH2 butanamide; butryamide (common) O ||

B.

CH3C–N(CH2CH3)2 N,N-diethylethanamide; N,N-diethylacetamide

18

Learning Check AM4 Draw the structures of A. Pentanamide B. N-methylbutyramide

19

Solution AM4 A.

Pentanamide O ||

CH3CH2CH2CH2C–NH2 B.

N-methylbutyramide O ||

CH3CH2CH2C–NHCH3

20

Reactions of Amides Amides undergo acid hydrolysis

base hydrolysis

carboxylic acid ammonium salt

salt of carboxylic acid and an amine or ammonia 21

Reactions of Amides acid hydrolysis

O ||

O

HCl + H2O

CH3COH + NH4+Cl–

||

CH3CNH2

O NaOH

||

CH3CO– Na+ + NH3 base hydrolysis

22

Learning Check AM5 Write the products of the hydrolysis of N- ethylpropanamide with NaOH.

23

Solution AM5 Hydrolysis of N-ethylpropanamide with NaOH gives the following products. O ||

CH3CH2CO– Na+ + CH3CH2NH2

24