The document provides an extensive overview of amines, including their classification, physical properties, and basicity. It discusses their preparation methods, reactions, and qualitative tests for identification. Additionally, it highlights specific amines and their applications in various fields.

1. AMINES
Mr. Mote G.D.
ADCBP, Ashta Dist: Sangli
Maharashtra

2. AMINES
• Amines are derivatives of ammonia in which
one or more hydrogen atoms have been
replaced by alkyl group.
CH3 NH2
Methyl amine
CH3 N H
CH3
Dimethyl amine
CH3 N CH3
CH3
Trimethyl amine

3. AMINES
Physical Properties:
1. Lower amines are liquid in nature.
2. IR stretch for N-H 3300-3500cm-1
3. Amines water insoluble because of N-H
bonds they are not forming hydrogen bond
with water, but soluble in organic solvents.
4. H1NMR shows peak between 0.5-5.0 

4. Classification of amines
• Primary amines: A amine has only one alkyl group directly
attached to the nitrogen.
• Secondary amines: A amine has two alkyl group directly
attached to the nitrogen.
• Tertiary amine: A amine has three alkyl group directly
attached to the nitrogen.
CH3 NH2
Methyl amine
CH3 N H
CH3
Dimethyl amine
CH3 N CH3
CH3
Trimethyl amine

5. Basicity of amines
• Amines are act as Lewis base because it denotes lone pair of
electron to form a new bond to a hydrogen.
R NH2
H2O RNH3
OH
Kb= (RNH3)(OH-)
(RNH2)
If the base is strong at that time equilibrium shifted to right and Kb value is higher
The strength of base is measured in terms of pKa value, more pka value indicates more
basic.
Kb= (H3O)(RNH2)
(RNH3)
R NH3
H2O H3O RNH2
Measurement of amine basicity through acidity of conjugate acids.
Equilibrium shifted to right and pKa value will be greater for conjugated acid.

6. Basicity of amines.
Sr. No name Pka of conjugate
acid
1 Diethyl amine 10.98
2 Dimethyl amine 10.64
3 Ethyl amine 10.63
4 Triethyl amine 10.65
5 Methyl amine 10.62
6 ammonia 9.3

7. Substituent effect on basicity
• Alkylation effect:
• Any factor that increases electron density on the N atom
increase an amine basicity.
• E. g. ammonia is least basic , alkyl group having electron
density hence alkyl group adds electron density means
alkylated ammonia is strong base
N
H
H H N
H
R H N
R
R H N
R
R R
1° 2° 3°
< < <
Ammonia
primary amine sec amine ter amine

8. Substituent effect on basicity
• Nature of amine:
• Any factor that decreases electron density on N atom, decreases
basicity.
• E.g the amine containing sp3 hybrid orbital having more electron
density but when carbon is sp2 and sp hybrid at that time electron
density on nitrogen decreases hence alkyl cyanides are least basic
than imines and amines.
RCH2NH2
RCH=NH
R-C N> >
AMINE
IMINE CYANIDE

9. Preparation of amines
1. Reaction of alkyl halide with ammonia.
2. Gabriel phthalimide method.
3. Reduction of nitroalkanes.
4. Reduction of nitriles.
5. Reduction of oximes
6. Reduction of isonitriles.
7. Reduction of amides.
8. Reductive amination of aldehyde and ketones.
9. Reduction of alkyl azide
10. Hoffman degradation of amide
11. Reduction of acyl azide( Curtis rearrangment)

10. 1. Reaction of alkyl halides with ammonia to form
amine
• Alkyl halides react with alcoholic solution of ammonia to form
amines.
10Mr. Mote G.D
H3C
H2
C NH3
CH3 CH2 NH2
ethyl amine
Br
HBr
ethyl bromide
Ethanol

11. 2. Gabriel phthalimide method
• This involves the treatment of phthalimide with pottasium
hydroxide to form the potassium salt.
11Mr. Mote G.D
C
C
O
O
NH
KOH
C
C
O
O
NK
CH3CH2Cl
C
C
O
O
NCH2CH3
KOH/H2O
COOK
COOK
+ CH3CH2NH2
ethyl amine
Potassium phthalate
Phthalimide Potassiumphthalimide
n-ethyl phthalimide

12. 3. Reduction of nitroalkanes
• Primary amines can be obtained by reduction of nitroalkanes
with Ni or Pt.
12Mr. Mote G.D
H3C
H2
C H2
CH3 CH2 NH2
ethyl amine
H2O
Pt
3 2
NO2
Nitroethane

13. 4. Reduction of nitriles
• Primary amines can be obtained by reduction of nitriles with
Ni or Pt.
13Mr. Mote G.D
H3C
H2
C H2
CH3 CH2 CH2
n- propyl amine
Pt
2C N
ethyl cyanide
NH2

14. 5. Reduction of oximes
• Primary amines can be obtained by reduction of nitriles with
Ni or Pt.
14Mr. Mote G.D
H3C
H2
C H2
CH3 CH2 CH2
n- propyl amine
Pt
2C
H
N NH2
OH
+ H2O
propionaldehyde oxime

15. 6. Reduction of isonitriles
• Secondary amines may be obtained by reduction of isonitriles
with Pt.
15Mr. Mote G.D
H3C
H2
C H2
CH3 CH2 NH
Pt
2N C
ethyl isocyanides
CH3
N-methylethanamine

16. 7. Reduction of amides
• Primary amines can be obtained by reduction of simple
amides with lithium aluminium hydride
16Mr. Mote G.D
H3C
H2
C H2
CH3 CH2 CH2
LiAlH4
C NH2
NH2
propyl amine
O
Propionamide
2
-H2O

17. 8. Reductive amination of aldehyde and ketone
• Primary amines can be obtained by reduction of aldehyde with
ammonia with Ni or Pt.
• Secondary amine produced with treatment with primary amines
17Mr. Mote G.D
H3C
H2
C H2
CH3 CH2 CH2
NH3
C H
NH2
propyl amine
O
Propionaldehyde
-H2O
H3C
H2
C H2
CH3 CH2 CH2
CH3NH2
C H
H
N
O
Propionaldehyde
-H2O
CH3
N-methylpropan-1-amine

18. 9. Reduction of alkyl azides.
• Primary alkyl halides react with sodium azide to form alkyl
azides and further reduction with lithium aluminium hydride
to give primary amines.
18Mr. Mote G.D
H3C
H2
C CH3 CH2 CH2
NaN3H2
C Cl N
Propionaldehyde
ethanol
N N
LiAlH4
CH3 CH2 CH2 NH2
N2+
propyl amine

19. 10. Hofmann’s degradation of amides.
• Conversion amide into amine with the help of sodium hypo
halides is known as hofmann’s degradation.
19Mr. Mote G.D
H3C
H2
C Br2
CH3 CH2 NH2
NaOH
C NH2
O
Propionamide
4
Na2CO3
2NaBr
H2O
+
+ 2
ethyl amine
H3C
H2
C C N
O
NaOH Na+
+ OH-
H
H
+ OH-
-H2O H3C
H2
C C N
O
H
Br Br
H3C
H2
C C N
O
H
Br
OH-
+
-H2OH3C
H2
C C N
O Br
+Na
NaBr
H3C
H2
C C N_
O
N CH2 CH3CO H2O
CH3 CH2 NH2
Mechanism

20. 11. Curtis rearrangement.
• This reaction converts acyl azide to primary amine.
20Mr. Mote G.D
H3C
H2
C CH3 CH2 C
NaN3
C Cl
O
propanoyl chloride
O
N N N
H2OHeat
CH3 CH2 NH2
CO2 N2++
ethyl amine

21. Reactions of amines.
1. Salt formation
2. Reaction with alkyl halides
3. Reaction with acid chlorides
4. Reaction with nitrous acid
5. Reaction with benzenesulfonyl chloride
6. Carbylamines reaction
21Mr. Mote G.D

22. 1. Salt formation.
• Amines are bases and react with mineral acid to form
ammonium salt.
22Mr. Mote G.D
CH3 CH2 NH2
ethyl amine
H-Cl+ CH3 CH2 NH3Cl
ethyl ammonium chloride

23. 2. Reaction with alkyl halides.
• Primary amines can be obtained by reduction of nitriles with
Ni or Pt.
23Mr. Mote G.D
CH3 CH2 NH2
ethyl amine
CH3-Cl+
CH3 CH2 NH CH3
CH3-Cl
CH3 CH2 N CH3
CH3
-HCl
-HCl
N-methylethanamine
N,N-dimethylethanamine
CH3Cl
CH3 CH2 N CH3
CH3
CH3
Quaternary ammonium salt

24. 3. Reaction with acid chlorides.
• Primary amines react with acid chloride to form N-substitutes
amides
24Mr. Mote G.D
CH3 CH2
H
N
ethyl amine
H + CH3 C
O
Cl
-HCl
CH3 CH2
H
N C
O
CH3
acetyl chloride N-ethylacetamide

25. 4. Reaction with nitrous acid.
• Primary amines react with nitrous acid to form diazonium
salts and salt hydrolyzes to form alcohol
25Mr. Mote G.D
CH3 C
H
NH2
propyl amine
CH3
NaNO2
HCl, 0°C CH3 C
H
N2Cl
CH3
-N2, -Cl2
CH3 CH
CH3
H2O
CH3 CH
CH3
OH
propan-2-ol

26. 5. Reaction with benzenesulfonyl chloride
• Primary amines react with benzene sulfonyl chloride to form
n-alkyl benzene sulfonamide.
26Mr. Mote G.D
CH3 C
H
NH2
CH3
+ S
O
O
Cl
S
O
O
NH C
H
CH3
CH3
N-isopropylbenzenesulfonamide
HCl+

27. 6. Carbylamines reaction.
• Primary amines react with chloroform and solution of KOH in
ethanol to form isocyanides.
27Mr. Mote G.D
CH3 NH2
+ CHCl3 + KOH CH3 N C + KCl3 + 3H2O
methyl amine methyl isocyanide

28. Qualitative test for amines
Name of test Observation Inference
1. Salt test: 0.1 gm sample and 5 ml
10% HCl
Clear solution Amine present
2. Carbylamines test: 0.1 gm sample+2
drops of chloroform+ 2 ml Alc. KOH
Foul smell of
isocyanides
Primary Aliphatic or
Aromatic amine
3. Diazotization test: 0.1 gm of sample
+ 10 Drops of Conc. HCl, boil and cool
in ice water + 4-5 drops of NaNO2 in
water and 2-naphtol in NaOH
Yellow solid
Red color
Orange ppt
Secondary amine
Tertiary amine
Primary amine
4. Hinsberg Test: 0.1 gm sample+ 0.3
gm of benzene sulfonyl chloride+ 5-10
ml ice cold water
Yellow ppt dissolves
in 5% NaOH
PPT insoluble in 5%
NaOH
PPt soluble in 10%
HCl
Primary amine
Secondary Amine
Tertiary amine

29. Structure and uses
• Ethylene diamine: used in manufacturing of fuel additives,
bleach activators, chelating agents, corrosion inhibitors.
• Ethanolamine: it is used as feedstock in the production of
detergents, emulsifier, polishes, corrosion inhibitors, chemical
intermediates.
• Amphetamine: nerve stimulants, it treats attention deficit
hyperactivity disorder.
29Mr. Mote G.D
H2
C
H2
C NHO
H2C
CH2OH
CH2CH2OH
ethanolamine
C
H2
H2C
H2N
NH2
ethylene diamine
NH2
CH3
amphetamine