The chemistry of essential oils and artificial perfumes / by Ernest J. Parry.

  • Parry, Ernest J. (Ernest John)
Date:
1908
Catalogue details

Licence: In copyright

Credit: The chemistry of essential oils and artificial perfumes / by Ernest J. Parry. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    ESSENTIAL OILS. carbon recovered is not pinene, but camphene. The further action of hydrochloric acid on pinene results in the forma- tion of dipentene dihydrochloride, showing that a molecular rearrangement has taken place. Pinene yields a character- istic compound with nitrosylchloride, C10H16NOC1, which is of great use in identifying the hydrocarbon. It is best pre- pared (Ann. Chem., ccliii., p. 251) by adding 15 c.c. of fuming hydrochloric acid to a well-cooled mixture of 50 c.c. each of turpentine, glacial acetic acid, and ethyl nitrite. The nitroso- chloride separates as a crystalline precipitate, and can be washed with alcohol to purify it. It then melts at 103° and is optically inactive. By the action of alcoholic solutions of various amines on the nitrosochloride, characteristic nitrol- amines are formed, of the general formula /NO CioH16\ NHB1 where E is the amine radicle. Of these pinene nitrol-piperi- dine melts at 118° and pinene nitrol-benzylamine at 122°. By treating pinene nitrosochloride with alcoholic potash nitroso- pinene C10H15NO is obtained. This body forms monoclinic crystals melting at 132°. The action of bromine on pinene gives rise to a solid di-bromide C10H16Br2 melting at 169°, and possibly to a liquid tetrabromide. The exact constitution of pinene is still a matter of doubt, but the most probable formula for this, and those for several of the other terpenes, are given below. Camphene.—This is the only solid terpene known. It occurs to a small extent in a few essential oils, such as citronella, ginger and camphor oils. It occurs to a greater extent in the oil from Pinus Siberica, from which it can be separated in an impure condition. It is prepared artificially, 1 Baeyer, however, holds that their constitution is C,0H,a(NHR)Ns-O2 (RHN)C]0H]6.