can any1 give the tests to distinguish between primary, secondary and tertiary amines?

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Urvashi Yadav answered this

We have given all the distinguishing tests in our blog section, please refer to the given link:

http://blog.meritnation.com/

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Rashmi answered this

Primary, secondary and tertiary amines can be identified and distinguished by Hinsberg’s test. In this test, the amines are allowed to react with Hinsberg’s reagent, benzenesulphonyl chloride (C₆H₅SO₂Cl). The three types of amines react differently with Hinsberg’s reagent. Therefore, they can be easily identified using Hinsberg’s reagent.

Primary amines react with benzenesulphonyl chloride to form N-alkylbenzenesulphonyl amide which is soluble in alkali.

Due to the presence of a strong electron-withdrawing sulphonyl group in the sulphonamide, the H−atom attached to nitrogen can be easily released as proton. So, it is acidic and dissolves in alkali.

Secondary amines react with Hinsberg’s reagent to give a sulphonamide which is insoluble in alkali.

There is no H−atom attached to the N-atom in the sulphonamide. Therefore, it is not acidic and insoluble in alkali.

On the other hand, tertiary amines do not react with Hinsberg’s reagent at all.

Ayshwarya S Balan answered this

Yeah it's the Hinsberg test

R-NH2 + C6H5SO2Cl give R-NHSO2Cl. (soluble in NaOH) primary amine

R2NH + C6H5SO2Cl give R-NSO2Cl. ( in soluble in NaOH) secondary amine

Teritiary amine doesn't react

Pooja Shukla answered this

(i) Hinsberg’s Test: In this test, the amine is treated with Hinsberg’s reagent [benzene sulphonyl chloride] and shaken with aqueous KOH solution when the three amines behave in different ways.

A. 1º amine gives a clear solution which on acidification gives an insoluble N-alkyl benzene sulphonamide.

B. 2º amine gives an insoluble N, N dialkyl benzene-sulphonamide which remains unaffected on addition of acid.

C. 3º amine does not react at all. Therefore, it remains insoluble in KOH solution but dissolves on acidification to give a clear solution.

(ii) Isocyanide test (carbylamine test): Primary amines (aliphatic as well as aromatic) react with chloroform in the presence of alcoholic KOH to form foul smelling carbylamines.

Secondary and tertiary amines (aliphatic as well as aromatic) do not give this test.

Veeralakshmi answered this

We can apply Hinsberg's test to distinguish between primary, secondary and tertiary amines.

Primary amine reacts with benzenesulphonyl chloride forming N-alkyl benzenesulphonamide, which is soluble in alkali.

Secondary amine reacts with benzenesulphonyl chloride forming N, N-dialkyl benzenesulphonamide, which is insoluble in alkali.

Tertiary amines do not react with benzenesulphonyl chloride.

Veeralakshmi answered this

Test	Primary amine	Secondary amine	Tertiary amine
Action of CHCl₃ and alcoholic KOH. (Carbylamine test)	Bad smelling carbylamine (Isocyanide) is formed.	No action.	No action.
Action of CS₂ and HgCl₂. (Mustard oil test)	Alkyl isothiocyanate is formed which has pungent smell like mustard oil.	No action.	No action
Action of nitrous acid.	Alcohol is formed with evolution of nitrogen.	Forms nitrosoamine which gives green colour with phenol and conc. H₂SO₄(Liebermann's test).	Forms nitrite in cold which on heating gives nitrosoa- mine which responds to Liebermann's test.
Action of acetyl chloride.	Acetyl derivative is formed.	Acetyl derivative is formed.	No action.
Action of Hinsberg's reagent.	Monoalkyl sulphonamide is formed which is soluble in KOH.	Dialkyl sulphonamide is formed which is insoluble in KOH.	No action.
Action of methyl iodide.	3 molecules (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.