Chemistry of Essential Oils

(Tuis.) #1

LABIATE 265


WD20O 1*48315; not soluble in 10 volumes 70 per cent, alcohol; soluble
in about 8 volumes and more 80 per cent, alcohol with slight tur-
bidity (separation of paraffin) ; soluble in every proportion in 90 per cent,
alcohol.
III. Oil from highly faded herb which had ceased blossoming:
due 0-9336 ; aD - 20° 26'; ND20O 1-48441; acid number 1-8 ; ester number
S'l; soluble in about 7 and more volumes 80 per cent, alcohol, with
slight turbidity (separation of paraffin).
For the following investigation they used oil III. After repeated
fractional distillation, the lowest-boiling fractions were combined and
distilled several times over sodium. The portions obtained at a pres-
sure of 758 mm. showed the following properties :—
B.-p. 164° to 166°, 3-1 per cent, of the oil, d^ 0-8650, aD - 19° 29', nD Q 1-47548
„ 166° „ 168°, 5-6 „ „ „ dig 0 0-8645, OD - 20° 16', n^ 1-47705
„ 168° „ 170°, 2-6 „ „ „ d 0-8632, AD - 20° 15', nD 1-47753
All three fractions had a turpentine-like odour, and on oxidation
with permanganate in the presence of free sodium hydroxide, yielded
sodium nopinate. They consequently contained /2-pinene (nopinene),
which was thus for the first time detected in large quantity in an es-
sential oil. The fraction of the boiling-point 164° to 166° contained the
largest quantity of /3-pinene, so that the constants for this fraction pos-
sibly approach those of the hydrocarbon most closely. The free nopinic
.acid obtained from the sodium salt crystallised from benzene in long
needles with a silken lustre, of the melting-point 126° to 127'5°.
The principal constituent of the oil is a saturated ketone of the
formula CIOH 16 O, which is the active variety of pino-camphone, which
has been prepared in the inactive form synthetically, by Wallach, by
the reduction of nitrosopinene. The characters of the two bodies are
as follows:—
i Pinocamphone (Wallach) : Z-Pinocamphone from hyssop oil:
Boiling-point 211° to 213°. Boiling-point 211° to 212°.
V
0
-959. duo 0-9662.



h> 1-47273. "D20o 1-47421.
Mol. refr. 44-44. Mol. refr. 44-40.
Optical rotation 0°. Optical rotation - 13° 42'.
OIL OF ELSHOLTZIA CRISTATA.
The dry herb, EUJioUzia cristata, yields 2 per cent, of an oil which
is esteemed in Japan as an antipyretic and diuretic. The oil has a
golden-yellow colour and has the following characters :—



Specific gravity 0-970
Optical rotation - 2-7°
Acid value 0
Ester „ 1-8
„ „ (after acetylation) 14-7
The oil contains a ketone, which has been examined by Asahina and
Murayama,^1 and which has the following constants :—
Boiling-point at 10 mm...87° to 88°
„ 760
Specific gravity
Optical rotation
Refractive index


210°


0-9817



1-4842


1
Schimmel's Report.
Free download pdf