Chemistry of Essential Oils

(Tuis.) #1

CONIFEE^ 25


The oil had a very characteristic odour; it was pungent when freshly
distilled, and, after standing some time, was orange-like. The oil poly-
merised very considerably at its boiling-point. The 15 per cent, residue
remaining in the distilling flask solidified to a solid, amber-coloured mass
resembling colophony, insoluble in alcohol, but soluble in ether and
chloroform. To avoid loss of oil by polymerisation it must be distilled
under reduced pressure. The oil carefully purified and finally distilled
•over metallic sodium, had the following properties: Boiling-point, 60° at
21°
11 mm.; specific gravity, ^ 0*8460; refractive index, 1-4861; specific
rotation [a]D = - 12'36°.
This oil is also noteworthy, as it consists mainly of /2-phellandrene
which has.not previously been detected in any turpentine oil.


TURPENTINE FROM PINUS LAMBEKTIANA.


An oil obtained from oleo-resin collected during 1911 had the following
properties: specific gravity, 0'8663; index of refraction, 1-4728; specific
rotation [A]O = + 10*42°. Another sample of the oil had a specific
gravity of 0*8658 and an index of refraction of 1*4727, and gave the fol-
lowing results on fractionation :—

Temperature
(corrected).

°C


155-8-157-3


158-6


153-9


159-3


159-7


160-3


161*3


162-5


168-4


178-8


178-8 +


Distillate.

Observed.

2-98


9-33


10*78


10-34


10-70


9-79


9*94


9-54


7-67


5-11


13-62


Cumulative.

Per Cent.
2-98
12-31
23-09
33-43
44-13
53-92
63-86
73-40
81-07
86-18
99-80

d!5°
Specific
Gravity at
15° C.

0-9531


•S620


•8629


•8632


•8633


•8633


•8634


•8633


•8624


•8548


•9011


ND15°


Index of
Refraction
at 15° C.

1-4657


1-4693


1-4698


1-4701


1-4703


1-4708


1-4716


1-4726


1-4736


1-4721


1-4912


The oil contains a-pinene, /?-pinene, a very small amount of phellan-
drene (?), a hydrocarbon, probably of the aliphatic series, and a sesqui-
terpene which is probably aromadendrene.

TUEPENTINE FROM PLNUS EDULIS.

The oil had the characteristic odour of thuja leaf oil, due to the pre-
sence of a sesquiterpene; the specific gravity was 0*8680; the index of
refraction, 1-4707; and the specific rotation, [O]D = + 19-26°.
The oil contains a-pinene, /3-pinene, and cadinene, a compound which
has not previously been recorded as occurring in turpentine oils.
On fractional distillation the following results were obtained :—
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