— 5 o — 



whereas the fraction boiling at 168 to 169 showed a jy-\- 14° 40', that 

 boiling at 17 8° showed only <* D -(- o°35'. Warren, Beilstein and 

 Kupfer, as well as Wolpian, have isolated from cumin oil a hydro- 

 carbon, of which the b. p. is given as 15 6° and as 157 to 15 8°, and 

 to which Wolpian gave the name of hydrocuminene. After repeated 

 fractionation we succeeded in obtaining from i 1 ^ kilos hydrocarbon 

 11 g of a body with b. p. 158 to 168 and an odour of pinene. 

 Treated with nitrosylchloride a very small quantity of a nitroso- 

 chloride was obtained, of which the benzylamine-combination melted 

 at 120 to 1 2 3 . The presence of a -pinene could be more 

 readily proved by oxidation into active d-pinonic acid. The acid 

 melted at 68 to 69 and was identical with d-pinonic acid from 

 Greek oil of turpentine. It follows that the oil contains i- and 

 d-a-pinene. 



The fractions with higher b. p. contained, besides p-cymene, small 

 quantities of terpene hydrocarbons. p-Cymene was identified in the 

 familiar manner by oxidising with permanganate (hydroxy-z^propyl ben- 

 zoic acid, m. p. 155 to 156 ). When the cymene fraction was oxidised 

 it yielded a small proportion of sodium nopinate. The free nopinic 

 acid had m. p. 125 to 12 6° and was lsevorotatory. On oxidation 

 with permanganate it yielded nopinone, of which the semicarbazone 

 melted at 1 8 7 to 1 8 8 °, thus proving the presence of/?-pinene. Wolpian, 

 who had isolated considerable proportions of hydrocuminene from the 

 oil, has probably had to deal with a sample which was adulterated 

 with turpentine oil, and his hydrocuminene was certainly only a mix- 

 ture of a-pinene, /?-pinene, and p-cymene. 



Although it was just the fraction boiling at 17 8° which showed 

 the smallest rotation (<*d -f- °°35')> ^ y et absorbed about io°/o °f 

 bromine. With hydrochloric acid it yielded a solid dihydrochloride, 

 m. p. 4 8°, which, when mixed with dipentene dihydrochloride suffered 

 no reduction of the m. p. From the same fraction a nitrosochloride 

 was also obtained, but this only appeared in very small quantities 

 and only separated out in the solid form upon the addition of water, 

 alcohol and ether. These facts in any case point to the presence of 

 dipentene. 



The presence of terpinene could not be proved, neither from the 

 nitrosite, nor from the dihydrochloride of m. p. 5 2°, or the products of 

 oxidation. No fraction gave the nitrite reaction, and a considerable 

 phellandrene content is therefore out of the question. The results 

 of the oxidation with permanganate indicate a high probability of the 

 presence of /S-phellandrene, which proves that when small quantities 

 of phellandrene are present, identification by the nitrite reaction is 

 very often a failure. This also agrees with our observations in the 

 case of other oils. 200 g. of the fraction, b. p. 173 , were oxidised 



