Chemistry of Essential Oils

(Tuis.) #1

MONIMIACE^E 177


MONIMIACE^E.


OIL OF PABACOTO BAKK.
Paracoto bark is derived from an unknown species of Monimiacea,
which is found in Bolivia. Its essential oil has a specific gravity 0*9275
and optical rotation - 2° 8'.
The oil has been investigated by Jobst and Hesse
l
who isolated two
hydrocarbons which they termed a-paracotene and /3-paracotene, to
which they assigned the improbable formulae C 12 H 18 and C^H^ re-
spectively. Cadinene and methyl-eugenol are present in the oil.
Wallach and Eheindorff^2 consider that the two hydrocarbons above
mentioned were not pure individuals, but mixtures of terpenes. The
three bodies described by Jobst and Hesse as a-, /?-, and y-paracotol
have also been found to be mixtures of methyl-eugenol and cadinene.


OIL OF ATHEBOSPEKMA MOSCHATUM.
The leaves of Atherosperma moschatum yield from 17 to 27 per
cent, of essential oil, which has been investigated by Miss M. E. Scott.
3


The tree flourishes in the gullies among the Victorian ranges, and a
yield of from 17 to 2-65 per cent, of oil is obtained from the leaves.
During the steam distillation of the oil it was noticed that the first
portion of the oil (about 30 per cent.) was lighter than water, whilst
that which subsequently passed over was heavier than water and sank
to the bottom of the vessel. The oil has the following characters :—
Specific gravity 1
0270
Opt.cal rotation + 7-5°
Refractive index 1*5211
The oil was distilled at 100 mm. pressure and divided into 16
fractions boiling from 99° to 183°. The optical rotation of fractions
1 to 9 ranged from + 61



  • 7° to 17°, the remaining fractions being optically
    inactive. The specific gravity of the first fraction was 0
    881 and that
    of the last 1034, the corresponding refractive indices being 14687 and
    15322.
    The sixteen fractions were subsequently subjected to repeated frac-
    tional distillation at ordinary pressure and the following compounds
    identified:—
    (a) Pinene C 10 H 16. A fraction was obtained boiling at 157° to 158°.
    Its combustion figures agreed very closely with the formula C 10 H 16 , and
    it yielded a hydrochloride melting at 130° and a nitrosochloride melting
    at 103°.
    (b) Camphor C 10 H 16 O. Five successive fractions yielded a solid
    substance, which, when freed from adherent oil, was white and crystal-
    line, and possessed the characteristic odour of camphor. It melted at
    174° to 176°, and had a specific rotation of + 40
    66° in 10 per cent,
    alcoholic solution. Its combustion figures agreed with those for C 10 H 16 O.
    (c) Eugenol methyl ether C 1 1HJ 4 O 2. The greater portion of the oil,
    after repeated fractionation was a pale yellow liquid distilling at 251°
    to 252° at 755 mm. pressure. Its combustion figures agreed with the
    formula CnH 14 O 2 , and it formed a bromo derivative melting at 75°. Its
    identity with eugenol methyl ether was therefore established.
    l
    Annalen, 199 (1879), 75.
    2
    3 Ibid., 271 (1892), 300.
    Jour. Chem. Soc. (1912), 1612.
    VOL. I. 12

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