Chemistry of Essential Oils

(Tuis.) #1

SANTALACE^E 187


(a) a-santalol, boiling at 300° to 301° at 760 mm., or at 162° to 163°
at 13 mm.; of specific gravity 0-9854 at 0° and optical rotation - 1° 20'.
(b) 0-santalol, boiling at 170° to 171° at 14 mm., or 309° to 310° at
760 mm.; of specific gravity 0*9869 at 0° and optical rotation - 56°.
a-santalyl acetate boils at 308° to 310°. /3-santalyl acetate boils at
316° to 317
°
.
Schimmel & Co., on the other hand (loc. cit.), give the following
characters for the two bodies :—

Specific gravity
Optical rotation.
Refractive index.
Boiling point at 5 mm..

a-Santalol.

. 0-9788 at 15°



  • 1° 13'
    1-49915
    148°


/3-Santalol.
0*9728


  • 41° 47'
    1-5091
    158°
    /?-santalene boils at 125° to 127° at 9 mm., has a specific gravity
    0892 at 20°, refractive index 1-4932, and optical rotation - 35°.
    Semmler and Bode
    l
    have shown that santalol is a primary alcohol
    (or alcohols), by its oxidation to santal aldehyde. According to these
    chemists this aldehyde boils at 152° to 155° at 10 mm., has a specific
    gravity 0-995 at 20°, refractive index 1
    51066, and is dextro-rotary. Its
    semicarbazone melts at 230°.
    Santalyl chloride, obtained by the action of phosphorus pentachloride
    on the alcohol, has a specific gravity 1-0398. Its formula is C 15 H 23 C1
    according to Semmler, who regards santalols as C 15 H 24 O.
    Semmler regards a-santalol as a tricyclic compound, which, when
    heated to 160° with alcoholic potash for two hours, is ruptured at the
    double bond in the side chain, and the tricyclic compound is converted
    into a dicyclic alcohol which he calls dicycloeksantalol. The formulae
    for the a and /2-santalols which he suggests are as follows :—


^ CH : CH. CH 2. CH. CH 2. OH.

a-Santalol.

CH : CH. CH 2. CH 2. CH 2. OH.


0-Santalol.
These abstruse points are dealt with fully in the following papers—
Berichte, 1907, 40, 1120, and 1907, 40, 1124.
By means of the strychnine salts, Paolini and Divizia
2
have separated
the two alcohols in a pure state. The mixture of the two alcohols as
found in sandal-wood oil is first carefully fractionated and the fractions
separately treated with sodium and converted into the hydrogen phthalate,
in the usual manner. The strychnine salts are then formed and recry-
stallised until the melting-point and rotatory power are constant. The
pure isomerides are then obtained by saponification. The purity ia
confirmed by reconverting into the strychnine salts, which should yield
on saponification a santalol of identical properties. The strychnine
phthalate of a-santalol melts at 155°, and has an optical rotation of


'Berichte (1907), 1124.
*
Alt. R. Acad. Lin. (1914), 23, 226.
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