- 174 — 



stants: b. p. 165 to 170° (10 mm.), d 20 o 1,0509, « D20O — 32°24 r , n D 1,4882.* 

 When oxidised with 27°/o nitric acid, cedrene keto acid yields an acid 

 C14H22O (m. p. 182,5°), to which the authors give the name of cedrene di- 

 carboxylic acid, and of which the dimethylester had the following characters : 

 b. p. 179 to 183° (13 mm.), d 20 o 1,0778, « D — 31°36 f , n D 1,48084. 



The fact that cedrene keto acid C15H24O3 is a methyl keto acid, which 

 compares uniformly with dicarboxylic acid C14H22O4 was confirmed by 

 its giving rise to dicarboxylic acid when oxidised with alkaline bromine 

 solution. 



Semmler and Risse consider that the preparation of cedrene dicarboxylic 

 acid C14H22O4 affords an excellent means of detecting the presence of cedrene 

 in essential oils. 



Caryophyllene. So far, the santalols and santalenes were the only 

 sesquiterpene bodies of which the structure was known, but recently 

 Semmler and E. W. Mayer 1 ) have succeeded in clearing up the principal 

 outlines of the molecular structure of caryophyllene. As the researches 

 of Deussen 2 ) have shown caryophyllene to consist of a mixture of several 

 hydrocarbons, it was not an easy matter to elucidate the structure of this 

 body. The proneness of caryophyllene to inversion renders its investigation 

 extraordinarily difficult. For example, the authors look upon the compound 

 C14H22O, which was obtained by Deussen and by Haarmann 3 ) in the course 

 of oxidation with permanganate of potassium, as being not a derivative of 

 the original caryophyllene, but a product of inversion, possibly of tricyclic 

 tsocaryophyllene. The only method by which useful results can be expected 

 is oxidation with ozone, and as a matter of fact, Semmler and Mayer have 

 succeeded, by gradually oxidising caryophyllene by means of ozone, in 

 obtaining bodies which are in the main derived from two caryophyllenes. 

 These they call terp.-caryophyllene and lim.-caryophyllene, and they assign 

 to them for the present two formula? which are analogous to those of 

 terpinolene and limonene, as follows: — 



H 3 CC 



CH2 CH 3 



H 2 C CH 3 



Terp. -Caryophyllene. 



*) Berl. Berichte 44 (1911), 3657. 



2 ) Comp. Report November 1908, 176; April 1909, 124; 



3 ) Comp. Report October 1909, 177. 



CH CH 3 



Lim. -Caryophyllene. 

 October 1909, 177; April 1910, 169. 



