Amines

Amines

nitrogen-containing organic compounds which can be classified as primary, secondary, or tertiary based on the number of alkyl (R-) groups attached to the nitrogen atom

Amines

basic and have a characteristic fishy odor and can exist as liquids (low carbon) or solids (higher carbon) depending on the number of carbons.

hydrogen bonding

The presence of H atoms results into ______________ which cause higher boiling for primary amines (BP primary > secondary > tertiary).

water

Amines are soluble in __________ due to its ability to undergo H-bonding.

decreases

as the size of the alkyl group increases, water solubility _________________

Aromatic amines (ex. Aniline)

readily undergoes atmospheric oxidation can gets colored as a result

Hinsberg Test

Procedure:

1. In a test tube, place approximately 0.3 mL of the sample.

2. Add 5 mL 10% NaOH and 0.4 mL benzene sulfonyl chloride.

3. Cover the test tube (with parafilm). Shake vigorously for 5 mins. Observe for results.

10% NaOH and benzene sulfonyl chloride

reagents of Hinsberg Test

Hinsberg Test

uses benzene sulfonyl chloride to differentiate between primary, secondary, and tertiary amines

Solubiliity with HCl and NaOH

Procedure:

1. Test the resulting solution from Hinsberg test for alkalinity using a litmus paper.

2. If solution is not alkaline, add 4M KOH dropwise until alkalinity is achieved.

3. Place test tube in a rack and stand the alkaline solution for 10 minutes.

4. After standing, add 6M HCl dropwise, until solution is acidic. Note for results.

5. If a precipitate forms, collect the precipitate. Place the precipitate in a test tube with 3 ML of 2.5 NaOH.

6. Heat the solution in a water bath. Shake for 2 mins. Note for results.

alkali soluble sulfonamide product

HINSBERG TEST:

a. Primary amines forms __________________________________.

b. Secondary amines forms ___________________________________.

c. Tertiary amines __________.

a = ?

alkali insoluble sulfonamide product

HINSBERG TEST:

a. Primary amines forms __________________________________.

b. Secondary amines forms ___________________________________.

c. Tertiary amines ________________.

b = ?

do not react

HINSBERG TEST:

a. Primary amines forms __________________________________.

b. Secondary amines forms ___________________________________.

c. Tertiary amines ______________________

c = ?