— 144 — 



The first originates from Wallach (1891), the second from 

 Harries 1 ), and the last has up to the present not yet been taken 

 into account, but comes to the front owing to the relationship between 

 sabinene and terpinene. This formula would not, however, explain 

 the derivation of the nitrosite from a semicyclic methene hydrocarbon, 

 as in such case the reduction should yield an aldehyde, and not a ketone 

 of the carvone series. The situation would become clear if, as 

 Wallach accepts, there were several modifications of terpinene. 



To Semmler's statement that previous to the discovery of 

 terpinene dihydrochloride it was possible to form exactly the same 

 picture of the relations of sabinene, Wallach 2 ) replies that not 

 theoretical discussions, but only the experimental realisation enable 

 one to form a clear idea of a reaction. 



A further communication by Semmler 3 ) regarding the con- 

 stitution of terpinene, origanol, sabinene, dipentene, and 

 their derivatives, deals only with the above-mentioned works of 

 Wallach, and supplies no fresh experimental material. Semmler 

 endeavours to defend his views, and to put an end to differences of 

 opinion which have arisen. 



Phellandrene. As a supplement to their work 4 ) on the synthesis 

 of phellandrene from carvomenthene dibromide, Kondakow and 

 Schindelmeiser 5 ) state that they have obtained from their inactive 

 hydrocarbon two nitrites whose melting points (102 to 103,5°, an d 

 94 to 95°) very nearly agree with those of the /?-phellandrene nitrites 6 ). 

 The formation of phellandrene from carvomenthene dibromide proceeds 

 therefore as follows: — 



CHBrCH 2 CHCH 



H 3 C— Brc/ ~\CH-C 8 H 7 = 2HBr + H 2 C:c/" =\CH — C 8 H 7 . 



C H 2 C H 2 C H 2 C H 2 



From the previously obtained chlorides of ^-phellandrene from oil 

 of water fennel, there were produced, by means of further purification, 

 two solid chlorides, viz., dipentene dihydrochloride (m. p. 50°), and 

 pinene hydrochloride (m. p. 12 6°). But the manner of identifying these 

 bodies is not mentioned. The intermediate fraction obtained in the 



1 ) Berl. Berichte 35 (1902), 1169. 



2 ) Berl. Berichte 40 (1907), 584. 



3 ) Berl. Berichte 40 (1907), 751. 



4 ) Journ. f. prakt. Chem. II. 72 (1905), 193; Report April 1906, 113. 



5 ) Journ. f. prakt. Chem. II. 75 (1907), 141, 



6 ) Instead of the designations pseudo- and /^-phellandrene which Kondakow 

 and Schindelmeiser use in turn, the uniform name /^-phellandrene may be 

 recommended. 



