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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


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


(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


Hinsberg's test: Shake

the sample of amine with

benzenesulphonyl chloride

Phenylmethyl


which is insoluble in KOH.

A clear solution of

ethylsulphonamide is

formed which is soluble in

KOH and insoluble in acid


(C6H5NHCH3)

Aniline (C6H5NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.






Phenylmethyl



A clear solution of

phenylsulphonamide is




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(C6H5NHCH3)

Benzylamine

(C6H5CH2NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.






Phenylmethyl



A clear solution of

benzylsulphonamide is




(C6H5NHCH3)

Triemethylamine

(CH3)3N




Phenylmethyl



No reaction

TEST Trimethylamine (CH3)3N Ethyl amine (C2H5NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.



TEST Trimethylamine (CH3)3N Aniline (C6H5NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.



TEST Trimethylamine (CH3)3N Benzylamine

(C6H5CH2NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.



TEST Trimethylamine (CH3)3N Dimethylamine

(CH3)2NH

Hinseberg test:

Hinsberg's test:Shake the



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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in KOH.

TEST Dimethylamine (CH3)2NH Ethyl amine (C2H5NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.



TEST Dimethylamine (CH3)2NH Aniline (C6H5NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.



TEST Dimethylamine (CH3)2NH Benzylamine

(C6H5CH2NH2)

Carbylamine test:


with CHCl3 in the


KOH

No action.



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)




aqueous solution of

NaNO2 is added

Ethanol is formed with

evolution of nitrogen gas as

bubble

Formation of

diazoniumchloride

TEST Methylamine (CH3NH2) Aniline (C6H5NH2)




aqueous solution of

NaNO2 is added

methanol is formed with


bubble

Formation of

diazoniumchloride

TEST Methylamine (CH3NH2) Dimethylamine

(CH3)2NH




aqueous solution of

Methanol is formed with


bubble

No evolution of nitrogen

gas



of 19

NaNO2 is added

TEST Methylamine (CH3NH2) Diethylamine (C2H5)2NH




aqueous solution of

NaNO2 is added



bubble


gas

TEST Methylamine (CH3NH2) Trimethylamine (CH3)3N




aqueous solution of

NaNO2 is added



buble


gas



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