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AMINES
Amines: amines are derivatives of ammonia (NH3), obtained by replacement of one, two or all the three hydrogen
atoms by alkyl and/or aryl groups.
Example:
In nature amines are present in - proteins, vitamins, alkaloids and hormones.
Synthetic amines are present in polymers, dyestuffs and drugs.
Table 1 -Some amines, their nature and function
Name of some
compounds
Nature Function/Use
Adrenaline secondary amine increase blood pressure
Ephedrine secondary amine increase blood pressure
Novocain synthetic amino compound an anaesthetic in dentistry
Benadryl Compound having tertiary amino
group
antihistaminic drug
Cationic Detergent Quaternary ammonium salts surfactants
Diazonium salts Have diazo group the preparation of a variety of aromatic
compounds including dyes
STRUCTURE OF FUNCTIONAL GROUP:
Nitrogen orbitals in amines are sp3 hybridised and the geometry of
amines is pyramidal.
Each of the three sp3 hybridised orbitals of nitrogen overlap with orbitals
of hydrogen or carbon depending upon the type of the amines.
The fourth orbital of nitrogen in all amines contains a loan pair of
electrons.
Due to the presence of loan pair of electrons, the angle C–N–E, (where E
is C or H) is less than 109.5° (in case of trimethylamine, it is 108o)
Due to the presence of loan pair of electron, amines are basic in nature.
CLASSIFICATION:
If 1 hydrogen atom of ammonia is replaced by R or Ar , we get
RNH 2 or ArNH2, a primary amine (1o).
If 2 hydrogen atoms of ammonia or one hydrogen atom of R-
NH2 are replaced by another alkyl/aryl (R’) we get R-NHR’,
secondary (20) amine.
If all the 3 hydrogen atoms of ammonia or two hydrogen atom
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of R-NH2 are replaced by another alkyl/aryl (R’) we get R-
NRR’, tertiary (30) amine.
Amines are said to be ‘simple’ when all the alkyl or aryl groups
are the same, and ‘mixed’ when they are different.
Amines in which the nitrogen atom is directly linked to 1, 2 or 3
(same or different) alkyl groups are called aliphatic amines.
These may be 10, 20 or 30
Amines in which the nitrogen atom is directly linked to 1, 2 or 3
(same or different) aromatic rings or aryl group are called aryl
amines. These may be 10, 20 or 30
Amines in which the nitrogen atom is linked to side chain/s of
1, 2 or 3 (same or different) aromatic rings are called aryl
amines. These may be 10, 20 or 30
Aniline Diphenylamine
Triphenylamine
Benzylamine Dibenzylamine
Nomenclature
i. Common name = alkyl amines (name of the
alkyl groups + amine using the prefixes di-
and tri-)
Example: CH3CH2NH2 (CH3CH2)2NH
(CH3CH2)3N
Ethylamine diethylamine
triethylamine
Common name of mixed amines = N-substituted
derivatives of the largest group of primary amine.
Example: (C2H5)2NCH2CH2CH2CH3 - N, N - diethyl
butylamine
ii. IUPAC name = alkane - e + amines =
alkanamine
Example: CH3NH2 is methanamine.
In case, more than one amino group is present at
different positions in the parent chain, their positions are
specified by giving numbers to the carbon atoms bearing
–NH2 groups and suitable prefix such as di, tri, etc. is
attached to the amine. The letter ‘e’ of the suffix of the
hydrocarbon part is retained.
Example : H2N –CH2–CH2–NH2 is named as ethane-1,
2-diamine
When additional functional groups such as -OH or
double bond are present in an amine, the prevailing
priority order for nomenclature is observed.
H2NCH2CH2OH2 is Amino ethanol
H2N CH2 CH = CH2 is Prop-2-ene-1 – amine.
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ISOMERISM IN AMINES:
TYPE OF ISOMERISM EXAMPLE
1. Chain isomerism is shown by amines having
four or more carbon atoms.
Butan-1-amine: CH3- CH2- CH2-CH2- NH2
2-Methyl propane -1-amine: (CH3)2CH-CH2-
NH2
2-Methyl propane -1-amine: (CH3)3C-NH2
2. Aliphatic amines having the same molecular
formula but different alkyl groups on the either
side of the nitrogen atom of –NH2 group show
metamerism.
Diethylamine: CH3-CH2-NH- CH2-CH3
Methyl n-propylamine: CH3- NH-CH2- CH2-
CH3
Isopropylmethylamine: CH3- NH-CH(CH3)2
3. Aliphatic amines containing 3 or more carbon
atoms show position isomerism due to the
difference in position of the amino group.
Aromatic amines
i.Pran-1-amine: CH3- CH2- CH2-NH2 &
Propan-2-amine: (CH3)2CH-NH2
ii.Butan-1-amine: CH3- CH2- CH2-CH2- NH2
&
Butan-2-amine: CH3- CH2- CH( NH2)-CH3
Similarly o-Toluidine, p-Toluidine, m-
Toluidine, show position isomerism.
4. 10, 20 & 30 amines having same molecular
formula show functional isomerism among
themselves.
Pran-1-amine: CH3- CH2- CH2-NH2 (10
amine)
N-methyl-ethylamine: CH3- CH2- NH-CH3
(20 amine)
N,N-dimethyl-methylamine: (CH3)3N (30
amine)
5. Tertiary amines of the type R1R2R3N though chiral exist as racemic mixtures which cannot be
resolved.
Quaternary ammonium salts of the type R1R2R3 R4N+X- exist as enantiomers.
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PREPARATION OF AMINES:
(Memory aid=[GHAR] means G=Gabriel , H= Hoffman bromamide, A= Ammonolysis, R= Reduction)
i.Gabriel phthalimide synthesis: Phthalimide on
treatment with ethanolic KOH forms potassium salt of
phthalimide which on heating with alkyl halide(R-X)
followed by alkaline hydrolysis produces the
corresponding primary amine.
Note:
This method is used for the preparation of 10
amines only.
Aromatic primary amines cannot be prepared by
this method because aryl halides do not undergo
nucleophilic substitution with the anion formed
by phthalimide.
2. Hoffmann bromamide degradation reaction- an
amide on reaction with bromine in an aqueous or
ethanolic solution of sodium hydroxide gives a primary
amine with one carbon less than the amide.
Significance Of this reaction: The reaction is used as-
i. method of preparation of 1amine
ii. step down conversion
Amide 1ºamine
Example:
CH3CONH2 + Br2 + 4NaOHCH3NH2
+Na2CO3+2NaBr +2H2O
Ethanamide Methylamine
C6H5CONH2 + Br2 + 4NaOHC6H5NH2
+Na2CO3+2NaBr +2H2O
Benzenamide Aniline
3. Ammonolysis of alkyl halides: the process of
cleavage of the C–X bond of alkyl halide by ammonia
molecule is known as ammonolysis.
RX + NH3 → RNH2 +HX [RNH3]+X-
The free amine can be obtained from the ammonium salt
by treatment with a strong base:
The order of reactivity of halides with amines: RI >
RBr >RCl
Aryl amines cannot be prepared by this method because
The process of converting an amine (10, 20 or 30) in to its
quaternary ammonium slat on treatment with excess of
an alky halide is called Exhaustive alkylation
Limitation:The product formed is a mixtur of 1º, 2 º, 3 º
amine and quaternary ammonium salt
4.BY REDUCTION:
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a. Reduction of nitriles (Mendius Reaction): both
aromatic and aliphatic nitriles on reduction with
lithium aluminium hydride(LiAlH4) or catalytic
hydrogenation or Na/C2H5OH produce
corresponding 1ºamine.
Significance: This reaction is used for ascent of
amine series, i.e., for preparation of amines
containing one carbon atom more than the
starting amine.
CH3C≡N –(H2/Ni) CH3CH2NH2
Ethanenitrile Ethylamine
C6H5C≡N + --(H2/Ni ) C6H5CH2NH2
Benzonitrile Benzylamine
b. Reduction of amides: amides on reduction with
lithium aluminium hydride (LiAlH4) or
Na/C2H5OH give 10 amine
c. Reduction of nitro compounds: Nitro
compounds are reduced to 10 amines by
I. passing H2 gas in the presence of Ni, Pd
or Pt
II. with metals in acidic medium (EG.
Sn+HCl)
III. LiAlH4
IV. Reduction of oximes: oxime can be
redueced into 10 amines using reducing
agents like Na/C2H5OH, or LiAlH4.
RCH=NOH + 4[H] LiAlH4 RCH2NH2 + H2O
V. Reductive amination of aldehydes and
ketones: Aldehydes and ketones react
with NH3/RNH2/R2NH in the presence of
reducinga agent like H2/Raney Ni or
sodiumcyano borohydride(NaBH3CN) to
give 10/20/30amines respectively.
5.aliphatic amines of low molecular mass are prepared
on industrial scale by passing amixture of an alcohol and
ammonia in the vapour phase over heated
alumina(Al2O3)
ROH + NH3 –( Al2O3, 575K) RNH2 –(ROH)
R2NH –(ROH) R3N
(R may be –CH3 or –CH2CH3)
Physical Properties:
1 Physical state: The lower aliphatic amines are gases with fishy odour. 10 amines with three or more carbon
atoms are liquid and still higher ones are solid.
2. Colour and odour: Aniline and other arylamines are usually colourless but get coloured on storage due to
atmospheric oxidation.
3. Solubility :
Lower aliphatic amines are soluble in water because they can form hydrogen bonds with water
molecules.
Solubility decreases with increase in molar mass of amines due to increase in size of the hydrophobic
alkyl part.
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4. Boiling point: 1º & 2º amines form intermolecular H- bonding. This H-Bonding is more in 1º amines
than in 2º amines as there are 2 hydrogen atoms available for H-bond formation in it. 3º amines do not form
H- bond. Therefore, the B.Pt. of isomeric amines follows the order: 1º> 2º > 3º
5. Basic Nature of amines: The reaction of amines with mineral acids to form ammonium salts shows
basic nature of amines. Amines have an unshared pair of electrons on N- atom due to which they act as
Lewis base.
For comparison of the basic character of amines, the equilibrium constant of following reaction is a measure of
their basic character.
Larger the value of Kb or smaller the value of pKb, stronger is the base.
Reaction of amine with mineral acid
Factors affecting basic strength of amines:
a) Inductive effect: Alkyl groups by their electron releasing effect, increase the electron density on
nitrogen and hence make the lone pair of nitrogen more easily available for sharing with acids. Also the
electron releasing effect of alkyl groups stabilizes the alkyl ammonium ion formed and hence shifts the
equilibrium in forward direction making the alkylamines stronger bases than ammonia
b) Steric effect the crowding of alkyl groups around N atom hinders the attack of proton on the amine
molecule and this decreases its basic strength. Since crowding of alkyl groups around N atom increases
from 1o to 3o amines, the basic strength of amine should decrease in the order 1o > 2o> 3o.
c) Hydration effect refers to the stabilization of the protonated amine by water molecules. The water
molecules from H - bonds with the protonated amine and release energy called hydration energy.
Greater the extent of H - bonding in protonated amine more will be its stabilization and consequently
greater will be the basic strength of the corresponding amine.
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a. Aliphatic amines are stronger bases then ammonia
Like ammonia, amines are strong bases and react with mineral acids to form ammonium salts from which they
can be liberated by treatment with a strong base like NaOH.
That alkylamines are stronger bases then ammonia due to electron releasing inductive effect of alkyl
groups. Alkyl groups by their electron releasing effect increase the electron density on nitrogen and
hence make the lone pair of nitrogen more easily available for sharing with acids. Also the electron
releasing effect of alkyl groups stabilizes the alkyl ammonium ion formed and hence shifts the
equilibrium in forward direction making the alkylamines stronger bases than ammonia.
stronger Lewis base stable alkyl ammonium ion
Thus the basic character of aliphatic amines in the gas phase should increase with increase of alkyl
substitution. In the gas phase, the expected order of basic strength is: 30 amine > 20amine > 10 amine >
ammonia(NH3)
b. Basicity of amines in the aqueous phase, the substituted ammonium cations get stabilized not only by
electron releasing effect of the alkyl group (+I) but also by solvation with water molecules. The greater
the size of the ion, lesser will be the solvation and the less stabilised is the ion. The order of stability of
ions are as follows:
When the -R group is small, like –CH3 group, there is no steric hindrance to H-bonding. In case the alkyl
group is bigger than -CH3 group, there will be steric hinderance to H-bonding. Therefore, the change of
nature of the alkyl group from -CH3 to –C2H5 results in change of the order of basic strength.
The combination of inductive effect, solvation effect and steric hinderance of the –R group which
decides the basic strength of alkyl amines in the aqueous state.
The order of basic strength in case of methyl substituted amines and ethyl substituted amines in
aqueous solution is as follows:
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c. Aromatic amines are weaker bases than ammonia and aliphatic amines.
Reason :
(i) Delocalization of one pair of electrons on the nitrogen atom
Due to resonance in aniline as shown below the lone pair of electrons on nitrogen is withdrawn from it and is
being partially shared with the benzene ring. Thus, in aniline the electron donating capacity of nitrogen for
protonation is considerably decreased as compared to that of ammonia and aliphatic amines. Hence aniline is a
weaker base than aliphatic amines and ammonia.
(ii) Lower stability of the anilinium ion
Anilinium ion formed by aniline by accepting a proton is not stabilized by resonance.
Anilinium ion only two canonical structures therefore less stable than aniline.
Anilinium ion is less stable as compared to aniline. Therefore, aniline has less tendency to accept proton to form
anilinium ion. This accounts for the lower basic strength of aniline.
d. Basicity of substituted aniline-
An electron releasing group present in an aromatic amine ring especially in ortho / para position will stabilize
the ammonium cation formed after the protonation of amine and hence increases the basic strength of
aromatic amine.
The electron releasing groups (like -OCH3, -CH3, -NH2 etc) enhance the availability of unshared electrons on
nitrogen and increases the basic strength.
Electrons withdrawing groups like (-NO2, -CN, -X etc) affect the stability of an aromatic ammonium cation
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and decreases the basic strength of parent aromatic amine.
The electron withdrawing groups decrease the availability of unshared electrons on nitrogen and thereby
decrease the basic strength of aromatic amines.
Ortho effect: Orthosubstituted anilines are generally weaker bases than aniline irrespective of the
electron releasing or electron withdrawing nature of the substituent. This is known as ortho effect and
may probably be due to combined electronic and steric factors.
Chemical Reactions:
The reactions of amines are mainly due to participation of unshared pair of electrons of nitrogen which makes them
react as a nucleophile. In aromatic amines, the unshared pair of electrons on the N atom facilitates electrophilic
substitution in the phenyl ring. The number of hydrogen atoms on the amine ring also effect the reactions.
Key Concept Reaction Example Note/ Comment
Nucleophilic
substitution
reaction: Like
ammonia(:NH3)
amines have lone
pair of electrons
therefore act as
nucleophile and
hence react with
electron deficient
compounds
(electrophiles) like
metal ions, alkyl
halides, acid
chlorides
With metal ions like
Ag+, Cu+2, etc.
AgCl + 2RNH2
[Ag(RNH2)2]Cl
AgCl + 2CH3NH2 [Ag(CH3NH2)2]Cl Only 10 amine shows
this reaction
Alkylation of 10
amine (RNH2)
RNH2 + R-X R2NH + H-X
CH3NH2 + CH3-Cl (CH3)2NH + H-Cl
Nucleophilic
substitution reaction
Alkylation of 20
amine (R2NH)
R2NH + R-X R3N + H-X
(CH3)2NH + H-Br (CH3)3N + H-Br
Alkylation of 30
amine , formation of
quaternary
ammonium salt
(CH3)3N + HCl(CH3)4N+Cl-
(This is Acid base reaction like NH3 +
HClNH4Cl
[R4N]+Cl- on
reaction with NaOH
regenerate amine
Acylation both
aliphatic and aromatic
1º and 2º amines react
with acid chlorides,
anhydrides and esters
to give amide
i. this is nucleophilic
substitution reaction
ii. reaction is carried
out in the presence
of a base stronger
than the amine, like
pyridine, which
removes HCl and
favours forward
reaction.
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Benzoylation of 10
amine- Nucleophilic
substitution reaction
(Schotten-Baumann
Reaction)
C6H5COCl + RNH2 C6H5CONHR + HCl
30 amines do not
show this reaction
With
Benzenesulphonyl
chloride
C6H5SO2Cl +
RNH2 C6H5SO2
NHR
C6H5SO2Cl +
HNR2 C6H5SO2
NR2
This compound is
acidic in nature,
soluble in alkali,
insoluble in base.
This compound is
insoluble soluble in
acid and alkali.
C6H5SO2Cl + NR3(30 amine) No reaction Guess why.
Electrophilic
substitution
reaction on
benzene ring of
Arylamines- due to
resonance in aniline
–NH2 group is
activating group and
meta director
Nitration on heating
with conc.HNO3 in
the presence of
conc.H2SO4
In strongly acidic
medium aniline is
protonated to form
Anilinium ion which
is m-director. That is
why beside o and p –
derivative ,
significant amount
of m-derivative is
formed
Bromination on
reaction with bromine
water
To prepare mono
substituted aniline , -
NH2 group is
protected by
acylation prior to
bromination
Sulphonation on
reaction with
conc.H2SO4
An ion which has
charge separation
but no net charge is
called Zwitter ion.
Friedel-Crafts
reaction (alkylation
and
acetylation)
Aniline does not undergo Friedel-Crafts
reaction
due to salt formation with aluminium
chloride, the
Lewis acid, which is used as a catalyst.
Due to this, nitrogen
of
aniline acquires
positive charge and
hence acts as a
strong deactivating
group for further
reaction.
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Carbylamine reaction/ isocyanide test:
Both 1º Aliphatic and aromatic amines on heating with chloroform and ethanolic KOH form isocyanides or
carbylamines which have foul smell.
Significance of the reaction:
i. This is a method of preparation of isocyanide
ii. 2º and 3ºamines do not show this reaction so this reaction is used – as a test for 1º amines.
Reaction with nitrous acid (HNO2)
a.1º aliphatic amines react with nitrous acid to form aliphatic diazonium salts which are unstable & decompose to
liberate N2 gas and alcohols.
b. 1ºAromatic amines react with HNO2 at low temperatures (0-5ºC) to form diazonium salts.
Significance: This reaction is used to –distinguish between 1º aliphatic & 1º aromatic amines
DIAZONIUM SALTS: General formula= ArN2 +X- , where Ar = an aryl group and X- may be Cl–, Br-, HSO4- ,
BF4- , etc.
Example: C6H5N2+Cl- is Benzenediazonium chloride.
C6H5N2+ HSO4
- is Benzenediazonium hydrogensulphate
(Named by suffixing diazonium to the name of the parent hydrocarbon from which they are formed, followed by
the name of anion. The
-N2+ group is called diazonium group.)
Preparation:
By diazotization: by the reaction of aniline with nitrous acid (HNO2) at 273-278K. HNO2 is produced in the
reaction mixture by the reaction of NaNO2 with HCl. The reaction is known as diazotisation.
Note:
i. 1º aliphatic amines form highly unstable alkyldiazonium salts.
ii. 1º aromatic amines form arenediazonium salts which are stable at low temperatures (273-278 K) due to
resonance.
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Due to its instability, the diazonium salt cannot be stored and is used immediately after its preparation.
Reactions involving displacement of nitrogen:
1. Replacement by halide or cyanide ion:
i. Sandmeyer reaction: Benzene The Cl–, Br– and CN– nucleophiles can easily be introduced in the benzene
ring by treating benzenediazoniumchloride with Cu2Cl2/ Cu2Br2/CuCN respectively in the presence
HCl/HBr/KCN.
ii. Gatterman reaction: Cl- or Br- can be introduced in the benzene ring by treating benzenediazonium salt
solution with corresponding halogen acid HCl/HBr in the presence of Cu powder.
2. Replacement of diazo group by iodide ion by warming with KI .
3. Replacement by fluoride ion:
Balz Schimann reaction:When arenediazonium chloride is treated with fluoroboric acid, arene diazonium
fluoroborate is
precipitated which on heating decomposes to yield aryl fluoride.
4. Replacement by H: Certain mild reducing agents like hypophosphorous acid (phosphinic acid) or ethanol
reduce diazonium salts to arenes and themselves get oxidised to phosphorous acid and ethanal, respectively.
The complete set of reactions starting from diazotization of aniline followed by reduction of diazonium salt or
replacement of the diazo group by hydrogen is called deamination.
5. Replacement by hydroxyl group(-OH): On heating diazonium salt solution upto 283 K, the salt gets
hydrolysed to phenol.
6. Replacement by –NO2 group: When diazonium fluoroborate is heated with aqueous sodium nitrite solution
in the presence of Cu, the diazonium group is replaced by –NO2 group.
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7. Replacement by phenyl group- Gomberg Bachman Reaction: Benzene diazonium chloride on
reaction with benzene in alkaline medium gives diphenyl.
Reactions involving retention of diazo group- coupling reactions
Benzene diazonium chloride reacts with phenol in which the phenol molecule at its para
position is coupled with the diazonium salt to form p-hydroxyazobenzene. This type of
reaction is known as coupling reaction. Similarly the reaction of diazonium salt with aniline yields
p-aminoazobenzene. This is an example of electrophilic substitution reaction.
(The azo products obtained have an extended conjugate system having both the aromatic rings
joined through the –N=N– bond. These compounds are often coloured and are used as dyes.) Importance of of Diazonium Salts in Synthesis - diazonium salts are very good intermediates for the introduction of –F, –Cl, –Br, –I, –CN, –OH, –NO2 groups into the aromatic ring.
(Note: Aryl fluorides and iodides cannot be prepared by direct halogenation. The cyano group cannot be introduced by
nucleophilic substitution of chlorine in chlorobenzene but cyanobenzene can be easily obtained from diazonium
salt.)
Liebermann nitroso reaction: Both aliphatic and aromatic secondary amines on reaction with nitrous acid(HNO2)
give yellow oily nitroso amines. Only aryl nitroso amines on heating with pheniol and conc H2SO4 acid gives
green colour which soon changes to blue –green which on dilution changes to red ad to blue or violet on reaction
with alkali.
(C2H5)2NH + [HNO2] --(NaNO2 + HCl) (C2H5)2N-N=O
Diethyl amine N- Diethylnitrosoamine
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Uses of amines:
1. Methylamine(CH3NH2): as refrigerant
2. Ethylamine(CH3CH2NH2):
For solvent extraction
In perfume industry
As stabilizer for rubber latex
3. Aniline (C6H5NH2):
For preparation of benzenediazonium salt
For synthesis of azodyes
For preparation of phenyl isocyanide
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Distinction between 10, 20 and 30 aliphatic amines
Test Primary amine Secondary amine Tertiary amine
1. Carbylamine test:
Sample of amine is
heated with CHCl3 in
the presence of
alcoholic KOH
Bad smelling
carbylamine
(Isocyanide) is formed.
R-NH2 +CHCl3+
KOH(alc)R-
NC+KCl+H2O
No action. No action.
2. Action of CS2 and
HgCl2. (Mustard oil
test)
Alkyl isothiocyanate is
formed which has
pungent smell like
mustard oil.
No action. No action
3. Action of nitrous
acid: Sample is
dissolved in HCl at
0-50C and to it cold
aqueous solution of
NaNO2 is added
Alcohol is formed with
evolution of nitrogen
gas as buble
R-NH2 +HNO2R-OH
+ N2
Forms yellow oily
product nitrosoamine
R2NH +HNO2R2-
N-N=O + H2O
This gives green
colour with phenol
and conc. H2SO4
(Liebermann's test).
Forms nitrite which is
soluble in water
R3N +HNO2
[R3NH]NO2
4. Action of acetyl
chloride.
Acetyl derivative is
formed.
Acetyl derivative is
formed.
No action.
5. Hinsberg's
test:Shake the
sample of amine with
benzenesulphonyl
chloride
A clear solution of
Monoalkyl
sulphonamide is formed
which is soluble in KOH
and insoluble in acid
Dialkyl sulphonamide
is formed which is
insoluble in KOH.
No action.
6. Action of methyl
iodide.
3 moles of CH3I to form
quaternary salt with one
mole of primary amine.
2 moles of CH3I to
form quaternary salt
with one mole of
secondary amine.
One mole of CH3I to
form quaternary salt
with one mole of
tertiary amine.
Conversion:
i. Step up Conversions: in this category of conversion the number of carbon atoms in the chain increases
,functional group remains the same.
Example: R-NH2 into R-CH2-NH2
Steps:
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ii. Step down Conversions: in this category of conversion the number of carbon atoms in the chain decreases
,functional group remains the same.
Example: R-CH2-NH2 to R-NH2
Steps:
Distinction between some important pairs of compounds:
TEST N-methylaniline
(C6H5NHCH3)
Ethyl amine
(C2H5NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
Hinsberg's test: Shake
the sample of amine with
benzenesulphonyl chloride
Phenylmethyl
sulphonamide is formed
which is insoluble in KOH.
A clear solution of
ethylsulphonamide is
formed which is soluble in
KOH and insoluble in acid
TEST N-methylaniline
(C6H5NHCH3)
Aniline (C6H5NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
Hinsberg's test: Shake
the sample of amine with
benzenesulphonyl chloride
Phenylmethyl
sulphonamide is formed
which is insoluble in KOH.
A clear solution of
phenylsulphonamide is
formed which is soluble in
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KOH and insoluble in acid
TEST N-methylaniline
(C6H5NHCH3)
Benzylamine
(C6H5CH2NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
Hinsberg's test: Shake
the sample of amine with
benzenesulphonyl chloride
Phenylmethyl
sulphonamide is formed
which is insoluble in KOH.
A clear solution of
benzylsulphonamide is
formed which is soluble in
KOH and insoluble in acid
TEST N-methylaniline
(C6H5NHCH3)
Triemethylamine
(CH3)3N
Hinsberg's test: Shake
the sample of amine with
benzenesulphonyl chloride
Phenylmethyl
sulphonamide is formed
which is insoluble in KOH.
No reaction
TEST Trimethylamine (CH3)3N Ethyl amine (C2H5NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
TEST Trimethylamine (CH3)3N Aniline (C6H5NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
TEST Trimethylamine (CH3)3N Benzylamine
(C6H5CH2NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
TEST Trimethylamine (CH3)3N Dimethylamine
(CH3)2NH
Hinseberg test:
Hinsberg's test:Shake the
sample of amine with
benzenesulphonyl chloride
No reaction Dimethyl sulphonamide is
formed which is insoluble
in KOH.
TEST Trimethylamine (CH3)3N Diethylamine (C2H5)2NH
Hinseberg test:
Hinsberg's test:Shake the
No reaction Diethyl sulphonamide is
formed which is insoluble
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sample of amine with
benzenesulphonyl chloride
in KOH.
TEST Dimethylamine (CH3)2NH Ethyl amine (C2H5NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
TEST Dimethylamine (CH3)2NH Aniline (C6H5NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
TEST Dimethylamine (CH3)2NH Benzylamine
(C6H5CH2NH2)
Carbylamine test:
Sample of amine is heated
with CHCl3 in the
presence of alcoholic
KOH
No action.
Bad smelling carbylamine
(Isocyanide) is formed.
TEST Benzylamine
(C6H5CH2NH2)
Aniline (C6H5NH2)
Action of nitrous acid:
Sample is dissolved in
HCl at 0-50C and to it cold
aqueous solution of
NaNO2 is added
Benzylalcohol is formed
with evolution of nitrogen
gas as bubble
Formation of
diazoniumchloride
TEST Ethyl amine (C2H5NH2) Aniline (C6H5NH2)
Action of nitrous acid:
Sample is dissolved in
HCl at 0-50C and to it cold
aqueous solution of
NaNO2 is added
Ethanol is formed with
evolution of nitrogen gas as
bubble
Formation of
diazoniumchloride
TEST Methylamine (CH3NH2) Aniline (C6H5NH2)
Action of nitrous acid:
Sample is dissolved in
HCl at 0-50C and to it cold
aqueous solution of
NaNO2 is added
methanol is formed with
evolution of nitrogen gas as
bubble
Formation of
diazoniumchloride
TEST Methylamine (CH3NH2) Dimethylamine
(CH3)2NH
Action of nitrous acid:
Sample is dissolved in
HCl at 0-50C and to it cold
aqueous solution of
Methanol is formed with
evolution of nitrogen gas as
bubble
No evolution of nitrogen
gas
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NaNO2 is added
TEST Methylamine (CH3NH2) Diethylamine (C2H5)2NH
Action of nitrous acid:
Sample is dissolved in
HCl at 0-50C and to it cold
aqueous solution of
NaNO2 is added
Methanol is formed with
evolution of nitrogen gas as
bubble
No evolution of nitrogen
gas
TEST Methylamine (CH3NH2) Trimethylamine (CH3)3N
Action of nitrous acid:
Sample is dissolved in
HCl at 0-50C and to it cold
aqueous solution of
NaNO2 is added
Methanol is formed with
evolution of nitrogen gas as
buble
No evolution of nitrogen
gas
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