6. TEST FOR PHELLANDRENE
Phellandrene readily yields a solid nitrite which
occurs as a voluminous flocculent precipitate in the following test.
Procedure:145 Into a test tube introduce a solution of 5 g.
of sodium nitrite in 8 cc. of water. Superimpose a solution of 5 cc. of the oil
in 10 cc. of petroleum ether. Add slowly 5 cc. of glacial acetic acid, shaking the
tube gently with a rotatory motion. A flocculent precipitate at the junction of
the two layers indicates the presence of phellandrene.
If large amounts of phellandrene are present,
the petroleum ether layer will solidify to a gel-like mass.
The crystals may be separated with a Blichner
funnel, and purified by filtering, washing with water and methyl alcohol, and finally
by dissolving the crystals in chloroform and then precipitating with methyl alcohol.
Since there are eight possible isomers, the melting point has little meaning unless
the physical isomers are separated.
0 Comment:
Post a Comment