— n5 — 



not accepted by Wallach 1 ), as just these terpenes are not "false", 

 but are specially characteristic. But as the need is felt to give a 

 name to this : C H 2 -group, which for example is present in limonene, 

 carvone, citronellal, isopulegone, and the phenols examined by Auwers 

 and Zincke, he calls it "methene". 



Terpinene. T. Amenomiya 2 ) supplies a contribution to the 

 constitution of terpinene with the continuation of his studies 3 ) of the 

 nitro-nitrosite of this terpene. If 5 gm. of this compound with 50 cc. 

 75 per cent, alcohol and 15 gm. zinc dust are heated to boiling, a 

 brisk reaction takes place, with development of nitrous acid. When 

 water is added, a syrup is precipitated, which finally becomes solid. 

 When distilled in a current of steam, a colourless oil passes over 

 which soon becomes crystalline. The product purified with methyl 

 alcohol melts at 91 to 92 °, and proved to be carvenone oxime. The 

 melting point of the semicarbazone of the carvenone obtained from 

 it lies at 204 . In the same manner terpinene nitrosite can be 

 reduced. According to this result one feels inclined to believe that 

 terpinene must be the carvenene which is derived from carvenone: 



CH, CH, 



CH 



H 9 C 



H 9 C 



C:N-OH 



CH 



H,C 



HX 1 



CH 



CH 



C.CH(CH 3 ) 2 



C.CH(CH 3 



Although the above result renders it probable that terpinene 

 nitronitrosite has the same carbon arrangement in respect of the 

 position of the double linkings, as terpinene, and that therefore during 

 the treatment with nitric acid a migration of the double linking from 

 Zl 4 to A s has not taken place, this does not settle the question whether 

 the very small quantity of carvenone oxime from the nitrosite must 

 not be considered as a product of conversion during the reduction. 

 But it may now be concluded from the formation of carvenone oxime, 

 that in the terpinene molecule a double linking is -in the A 1 position. 

 It would be a matter of interest to try whether a hydrocarbon can 

 be produced from carvenone which is identic with terpinene. 



1 ) Liebig's Annalen 343 (1905), 28. 



2 ) Berl Berichte 38 (1905), 2730. 



3 ) Berl. Berichte 38 (1905), 2022; Report October 1905, 100. 



