Organic chemistry ii
lab#6
Lab#6
Amines
Jawza A. Al mutairi
Teaching Assistant
Princess Norah Bint Abdulrahman University
Collage of pharmacy
Pharmaceutical Chemistry
Department
Introduction:
• Amines are derivatives of ammonia in
which one or more of the hydrogen's has
been replaced by an alkyl or aryl group.
Nomenclature:
• Amines are described as primary (1o),
secondary (2o), tertiary (3o) or quaternary
(4o) depending on how many alkyl
substituents are attached to the N atom
Nomenclature:
N-methyl aniline
N,N-dimethyl aniline
Aniline
Physical properties
Physical prosperities
Color: all amines are colorless, but when
expose to light the color well change.
Odor: characteristic.
Flammability: flammable with dark black
smock.
Solubility: immiscible in water, but micible in
HCL.
Effect in L.P: blue ( most of amines are base).
Chemical test
Chemical test
• Generalized test:
• FeCl3 test:
• Procedure: dissolve 1ml of amine in 3ml of
dil.HCL, then add 1ml of FeCl3.
Aniline: green color.
N-methyl amine: green color.
N,N-methyl amine: green color.
Aniline
N-methyl aniline
N,N-dimethyl aniline
Chemical test
• Specific test for aniline:
• Nitrous acid reaction:
• Procedure:
1) In test tube “1”, add 3 drops of aniline and
dissolve it with 2ml of dil.HCL, shack well.
2) Cool the test tube in iced water.
3) In test tube “2”, dissolve 0.5gm of NaNO2 in
5ml distal water.
Chemical test
4) add test tube “2” in test tube “1”, while
shaking gently.
P.S: if any ppt. formed, that mean the amount
dil.HCL that been added is not enough to
dissolve the aniline.
Chemical test
5) in beaker mix 1ml of phenol with 2ml of
30%NaOH, and add it to test tube “1”.
Result: crimson color [known as Azo pigment]
Aniline
Chemical test
• Specific test for aniline:
• Krbel amine test:
• Procedure:
add few drops of cloroform to the amine, then
add 2ml of NaOH or KOH. Heat on water
bath.
Result: Krbel amine odor.
Chemical test
• Specific test for 2nd and 3ry amine:
• Nitrous acid reaction:
• Procedure:
1) In test tube “1”, add 3 drops of aniline and
dissolve it with 2ml of dil.HCL, shack well.
2) Cool the test tube in iced water.
3) In test tube “2”, dissolve 0.5gm of NaNO2 in
5ml distal water.
Chemical test
4) add test tube “2” in test tube “1”, while
shaking gently.
Result:
N-methyl aniline: oily yellowish.
N,N-dimethyl aniline: red.
N-methyl aniline
N,N-dimethyl aniline
Chemical test
 For the N,N-dimethyl aniline, add few drops
of 10% NaOH, and leave it for 5 min.
Result: formation of green ppt.
N,N-dimethyl aniline
Chemical test
• Specific test for 3ry amine:
• Methylene Orange test:
• Procedure:
1) In test tube “1”, add few mg of HSo3 in 1ml
Na2CO3.
2) In test tube “2”, dissolve 0.5 mg of NaNO2 in
5ml distal water.
Chemical test
3) add 2-3ml of test tube “2” in test tube “1”,
while cooling it in iced water, the add few ml
of dil.HCL
4) in test tube “3”, dissolve 2-3 drops of amine
in 2 ml dil.HCL
5) add test tube “3” to test tube “1”.
Result: yellow color.
Chemical test
• Specific test for 3ry amine:
• Picric test:
• Procedure:
1) Dessolve 0.5ml of amine in acetone.
2) Add 2ml of Picric acetone solution, with
shaking.
Result: formation of yellow ppt.
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