Commercial and scientific notes on essential oils. 67 



the other species the following are mentioned: — Thymus hirtus, Willd., which thrives in 

 Central and southern Spain, on the calcareous hills round Granada and in the lower 

 regions of the Pinsapo Forest, Thymus hyemalis, Lange, in south-eastern Spain, Thymus 

 ccphalotus. L., in Valencia, in lower Asturia and, according to Dorronsoro 1 ) in Almeria, 

 Thymus ewspiticus, Brot, in Estremadura and Galicia, Thymus Piperella, L, in Valencia 

 on rocky slopes, Thymus cerpylloides, Bory, (Samarilla) in the alps of the Sierra Nevada. 

 To quite another species belongs the so-called Andalusian thyme (Tomillo andaluz 

 = tomillo carrasqueno) or Corydothymus, which according to Bias Lazaro 1 ) is Corydo- 

 thymus capitatus, Rchb. B. Dorronsoro' 2 ) writes about it as follows: — "Various kinds 

 of thyme are distilled in Spain, viz., the tomillo corriente (common thyme) === tomillo 

 aceitunero (olive thyme) = Thymus vidgaris. L., the tomillo risquero (thyme of the rocks) = 

 Thymus Zygis. L., the tomillo sanjuanero (St. John's thyme) = Thymus hyemalis, Lg., 

 and the tomillo carrasqueno (holm-oak thyme) or tomillo andaluz (Andalusian thyme), 

 which latter, however, is no real thyme, but Corydothymus capitatus, Rchb., belonging 

 to an allied species." 



In August 1915, we examined in our research laboratory a Spanish oil from 

 Barcelona, on whose botanical origin, unfortunately, nothing definite could be as- 

 certained. Since only very little positive is known as to the chemical composition of 

 the Spanish oils, the results of the following investigation gave no clue concerning 

 the botanical source of the oil. Owing to the war, the work had unfortunately to be 

 discontinued and was terminated only before long, when the oil had been left standing 

 for nearly six years (protected from direct light) after having been fractionated and 

 freed from phenols by treatment with dilute caustic lye. 



The original oil showed the following constants: — di 6 o 0.9297, « D -j-0°35', soluble 

 in 3.5 vols, and more of 70 per cent, alcohol; phenols 45 per cent., for the greater 

 part thymol. 



The most volatile fraction of the b. p. 130 to 132° smelled of amyl alcohol and 

 gave the characteristic naphthylurethane, m. p. 51 to 52° obtained by us on a previous 

 occasion. In the fractions of b. p. range 132 to 150° we suspected owing to their 

 amylaceous smell the presence of amylcarbinols. Since they consisted doubtlessly of 

 mixtures, contaminated possibly with small amounts of amylic or similar ketones, we 

 refrained from further isolation and identification. We only by way of experiment, 

 succeeded in isolating a naphthylurethane, m. p. 47 to 48°. We were unable to prove the 

 existence of a ketone, nor the formation of such by oxidation with bichromate solution. 



A small fraction, b. p. 145 to 150° (d l5 o 0.8495, « D -f-3°28', n D20 o 1.45052), yielded 

 on benzoylation with the aid of pyridine a benzoate, b. p. 134 to 135° (6 mm.), which 

 on saponification gave rise to an alcohol with the characteristic odour of fi,y-hexenol. 

 This alcohol had previously 3 ) been obtained by us in shape of its phenylacetate from 

 the last runnings of Japanese peppermint oil. Although the oil showed the same 

 boiling point (156°) as the above-mentioned alcohol, we were unable to raise the 

 melting point of the naphthylurethane beyond 58 to 60°, whereas the derivative of 

 the pure alcohol from peppermint oil melts at 72°. In spite of this discrepancy we 

 do not hesitate to accept the identity «of the alcohol with /? ; /-hexenol. A closer 

 examination carried out with more material will in all probability confirm this identity 

 and thus prove the existence of free /?.;'-hexenol in Spanish thyme oil. 



*) Cf. Bericht (German) 1921, 87. — 2 ) Estudio quvmico de esencias naturales espanolas. Madrid 1919, 

 p. 134. — *) R H)t ,rt 1918, 39; Walbaum, Journ. f. prakt. Chem. II. 96 (1918), 245. 



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