130 ODOROGRAPHIA. 



The investigations of Semmler,* show that its principal con- 

 stituent, amounting to 90 per cent, is an alcohol, C\ ^ H^ g 0, which 

 he named Coriandrol \ this boils at 194^-198° and is optically 

 dextro-rotatory, and has a sp. gr. of 0-8679 at 20*^ C. Eecent 

 investigations have been madef to determine the nature of the 

 other constituents of Coriander oil ; the first portions that distilled 

 over on rectification with steam w"ere repeatedly fractionated with 

 the aid of a Lebel-Henninger's column, and finally a fraction 

 was obtained boiling between loG^-lGO*^ C, with a sp. gr. of 

 0'861 at 15° C. In a 100 m. m. tube this showed an optical 

 rotation of + 32° 42'. The nitrosyl-chloride compound yielded 

 w^ith benzylamine, a base w^ith the melting point of 123°-124° 

 C, so that it evidently consisted of Pinene-nitrolbenzylamine. 

 Coriander oil therefore contains Dextro-pinene, the quantity of 

 which is estimated at about 5 per cent. 



According to a recent paper by Barbier,;!: coriandrol when 

 treated with acetic anhydride, gives rise to a dextro-rotatory 

 limonene, of which the physical and chemical properties are 

 identical with those of licarene (a dextrogyre variety of linalool), 

 together with an acetic ether of a stereo-isomeric alcohol corres- 

 ponding to licarJiodol and apparently identical with it. Barbier 

 considers therefore that coriandrol is but a dextro-rotatory 

 modification of licareol, differing in odour, but otherwise possessing 

 similar properties. The aldehyde (citral) formed from it by 

 oxydation is apparently identical with that derived from licareol, 

 and the evidence tends to prove that this alcohol exists in the two 

 modifications, differing in the direction of their rotatory power, 

 but otherwise practically identical. 



The frequency with which adulterated coriander oils occur, 

 especially in the American markets, renders it desirable to place 

 within the reach of consumers an easily applicable test for the 

 recognition of added foreign matter. The property of coriander 

 oil to dissolve in dilute alcohol offers a good starting point to 

 judge of its purity. Messrs. Schimmel & Co. state§ : — " Genuine 

 coriander oil should yield a clear solution when mixed with three 



* Ber. Deutsch, Chem. Ges., xxiv. p. 208. 

 t Schimmel and Co., Bericht, April, 1892. 

 Z Comptes Rendus, cxvi. [1893], p. 1459. 

 § Bericht, October, 1893. 



