The constituents of the essential oil of Californian laurel / by Frederick B. Power and Frederic H. Lees.

  • Frederick Belding Power
Date:
[1904]
Catalogue details

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: The constituents of the essential oil of Californian laurel / by Frederick B. Power and Frederic H. Lees. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    an excess of an alcoholic solution of sodium hydroxide, its pungent odour was not destroyed. The separation of the small amount of uncombined acids was effected by shaking the oil four times with dilute aqueous sodium carbonate and finally with water. The combined aqueous liquids, after shaking with ether to remove adhering oil, were evaporated to a small volume, acidified with sulphuric acid, and distilled in steam. From the distillate, ether extracted 2’3 grams of a light yellow, somewhat pungent, oily acid, which was converted through the ammonium salt into a silver salt. The latter formed a dense, white, amorphous precipitate, and was obtained in two fractions, which were analysed : (a) 0T523 gave 0'0495 Ag. Ag = 32'5. (b) 0T277 „ 0‘0599 Ag. Ag = 46'9 per cent. The aqueous liquid from which the oily acids had been extracted still contained an acid, which was converted into its barium salt. This was crystalline, but, in attempting to prepare the corresponding silver salt, the dense, white precipitate first produced almost immediately became reduced. Another portion of the barium salt gave a precipitate of calomel with a solution of mercuric chloride. The oil thus evidently contains an exceedingly small amount of formic acid, associated with a mixture of some higher fatty acids. Identification of Eugenol. The whole of the oil, after the removal of the fatty acids, was shaken six times with 5 per cent, aqueous potassium hydroxide, and finally several times with water. The combined alkaline liquids were then shaken with ether to remove adhering oil, and acidified with sulphuric acid, when a quantity of an oily liquid separated this was taken up with ether, the ethereal solution washed, dried, and the ether removed. The residual oil, amounting to 20 grams, was then dis- tilled under 80 mm. pressure, when it passed over completely between 170° and 175°, but principally at 170—172°. A fraction collected at the latter point was analysed : 0-1106 gave 0-2964 OO2 and 0-0749 Ufi). C = 73-l ; H = 7-5. requires C = 73-2 ; H = 7-3 per cent. It gave a blue coloration with ferric chloride, and afforded a benzoyl derivative, which, after crystallisation from alcohol, melted at 69—70°. It is thus shown that the oil contains an appreciable amount of eugenol.
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