Chemistry of Essential Oils

190 THE CHEMISTEY OF ESSENTIAL OILS

pecific

Gravity.

•962

•966

•953

•963

•962

Solubility in

70 per Cent.

Alcohol.

1in80

1 „ 55

Insoluble in 80

80

80

Rotation.

+ 25°

+ 8°

+ 30°

+ 25°

30'

20'

'75'

Alcohols as

Santalol.

Per Cent.

42

50-5

30-1

32-1

1

2

3

4

5

Mr. E. M. Holmes examined the plant yielding this oil, and named

it Schimmelia oleifera after the firm who obtained the specimens for

him, but Urban has now proved definitely that the plant belongs to the

genus Amyris, and has identified it as Amyris baisamifera.

It is now well recognised that the alcoholic body or bodies of West

Indian santal oil differ from the alcohols of the East Indian oil.

This alcohol has now been isolated by H. von Soden and named by

him "amyrol". It forms an almost colourless, viscous liquid, which

forms a clear solution with 3 to 3-J parts of 70 per cent, alcohol. Specific

gravity at 15° = 0'98Q to 0-982 ; aD = + 27°. Boiling-point at 748 mm.

pressure = 299° to 301°, at 11 mm. 151° to 152°.

Amyrol cannot be esterified with phthalic acid anhydride; quanti-

tative acetylation is equally impossible. Amyrol is probably a ses-

quiterpene alcohol, C 15 H 26 O. In addition to this body, West Indian

=sandal-wood oil contains a sesquiterpene, whose nature has been

investigated by E. Deussen. He introduced hydrochloric acid gas up

to saturation into the oil dissolved in dry ether, and obtained crystals

of cadinene dihydrochloride. The corresponding compounds of hydro-

gen bromide and iodide, of which the constants are given below, were

produced in a similar manner:—

Dihydrochloride.

Dihydrobromide.

Dihydroiodide

Melting-point

117° to 118°

124° „ 125°

105° „ 106°

Per Cent.

Cl.

25-65

Br.

43-64

I.

54-96

- 36*65

°

• 36-26°

It has more recently been found that amyrol, like santalol, is not a
uniform body, but that by frequently repeated fractional distillation it
•can be separated into different alcohols. The higher boiling, very
viscous compound has a faint, characteristic, fragrant odour; its
formula C 15 H 25 OH. Specific gravity about 0*987; aD = about + 36°;
boiling-point 299°. The lower boiling alcohol appears to have the
formula C 16 H 23 OH, and to be optically inactive.
The liquid obtained on saponifying the original oil, when acidified
with sulphuric acid, yielded an oil, partly congealing in crystalline
form, with an odour strongly reminding of acetic acid. This oil was
shaken with carbonate of sodium solution to remove the acid. The
remaining crystals, after recrystallisation from methyl alcohol, melted
at 117°. This new body, to which the name amyrolin was given,
contains neither nitrogen nor methoxyl groups; its composition is
C14HLIO3. Amyrolin dissolves in alcoholic potash solution with a
yellowish-green fluorescence, absorbs bromine, and yields with the