Chemistry of Essential Oils

CONIFERS 55

08698, refractive index 14696, and yields a nitrosochloride melting at
109° to 111°. Pinene is present in its various stereo-isomeric forms, as
well as camphene and phellandrene. The chief constituent, from the
odour point of view, is bornyl acetate. The sesquiterpene bisabolene is
present to a small extent in the high boiling fractions of the oil. Esters
of terpineol are also present to a small extent.

3. Oil of Pinus longifolia.—The leaves of the Indian pine tree, Pinus
   longifolia—the so-called " Chir " pine—yield an essential oil having the
   following characters :—
   Specific gravity at 20°.0-874
   Optical rotation
   Acid value
   Ester „
   Saponification value
   Iodine value
   Distils from 160° to 165°
   „ 165° „ 170°
   „ 170
   °
   „ 180°
   „ „ 180° „ 200°
   „ 200° „ 215°
   Residue above 215°

- 6° 15'

1-03

14-51

15-54

271-2

23-8 per cent.

29-0

19-8

15-1

6-7

5-6

These five fractions had the following physical characters :—

Fraction.

160° to 165°

165° „ 170°

170° „ 180°

180° „ 200°

200° „ 215°

Specific

Gravity at 20°

0-860

0-861

0-863

0-868

0-909

Rotation.

• 12° 12'


• 9° 15'


• 6°


• 3°


• 2°
  The ester value of this oil is 14

• 5, which corresponds to about 5 per
  cent, of esters calculated as bornyl acetate, which is, of course, to be ex-
  pected with an oil with the range of distillation temperatures indicated
  above; for bornyl acetate is sought for in essential oils in the fraction
  boiling at 220° to 230°, which is practically non-existent in the oil in
  question.

4. Oil of Pinus pumilio.—This oil, although usually classed as a pine-
   needle oil, is usually distilled from the leaves mixed with small twigs and
   woody portions of the branches of Pinus pumilio (Pinus montana Mill.).
   It is principally distilled in the Austrian Alps, largely in the Tyrol, and
   in several other districts. The yield of oil is, as would be expected, very
   variable, as low as 025 per cent, being obtained, or as much as 075 per
   cent. The oil has the following characters :—
   Specific gravity 0-863 to 0-876
   Optical rotation - 5° to - 10° (rarely to - 16°)
   Refractive index 1-4740 to 1-4800
   Esters as bornyl acetate ... 3 to 10 per cent.
   It is soluble in 5 to 10 volumes of 90 per cent, alcohol.
   These limits may be exceeded if the distillation material is not fresh,
   and oils with a specific gravity up to 0*892 have been recorded. The
   following fractions were obtained on distilling an authentic specimen of
   the oil:—x
   155° to 165°.
   165° „ 180°.
   180° „ 200°.
   above 200°.

2 per cent.

59 „

20

18

(^1) Umney, Pharm. Jour., 55 (1895), 163.