The constituents of an essential oil of rue / by Frederick B. Power and Frederic H. Lees. Methyl beta-methylhexyl ketone / by Frederic H. Lees.

  • Frederick Belding Power
Date:
[1902]
Catalogue details

Licence: In copyright

Credit: The constituents of an essential oil of rue / by Frederick B. Power and Frederic H. Lees. Methyl beta-methylhexyl ketone / by Frederic H. Lees. Source: Wellcome Collection.

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    6. Acetic acid, in combination with the alcohols. 7. A basic substance, having the odour of quinoline. • 8. A mixture of free fatty acids. 9. Methyl salicylate. 10. Ester of valeric acid, apparently ethyl valerate. 11. Pinene. 12. Z-Limonene. 13. Cineol. The relative proportion of the above constituents is approximately as follows : The two ketones represented 80 percent, of the oil, and were present in about equal amounts. The two alcohols represented about 10 per cent., and were present partly in the uncombined state and partly as acetic esters. The methyl-w-heptylcarbinol preponderated. • The two terpenes, together with cineol, represented about 1 per cent, of the oil. There was very little pinene, and the amounts of limonene and cineol were about equal. The amount of blue oil was about 0‘5 per cent., and finally there was separated from the non-ketonic portion of the oil a small amount of undistillable, viscous substance, which was probably a decomposition product. The fact that the substances associated with the ketones and alcohols are present in such small amount, and that the limonene is the more rarely occurring £-form, enables us to conclude that all these substances are natural constituents of the oil. The Wellcome Chemical Research Laboratories. CLIX.—Methyl fi-Methylliexyl Ketone. By Frederic Herbert Lees. In the course of an investigation of the ketones contained in an essential oil of rue (this vol., p. 1585), methyl fi-methylhexyl ketone, CH3*CO*CH2,CH(CH3)*[CH2]3,CH3, was prepared and characterised. It was obtained by the hydrolysis of ethyl seQ.-hexylacetoacetaie, CH3,C0*CH(C6H13)*C02Et, which was prepared by the condensa¬ tion of sec.-hexyl iodide (from mannitol) with ethyl acetoacetate. Ethyl sec.-hexylacetoacetate.—Sodium (5‘8 grams) was dissolved in absolute alcohol (60 c.c.), and to the solution were successively added, ethyl acetoacetate (32*5 grams), and sec.-hexyl iodide (53 grams). The
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