— Ill — 



at 64 , and of the racemic linalool at 66°. For linalool, Tiemann- 

 Semmler's formula could be confirmed. The corresponding ocimenol 

 yielded a phenyl urethane of the melting point 7 2°. 



When heated in a reflux-condenser, ocimene is converted (accord- 

 ing to van Romburgh) into an isomeric "alloocimene" ; Enklaar 

 considers the latter a geometric-isomeride , as it yields on reduction 

 the same dihydro product as ocimene. Attempts made to arrive at 

 the corresponding alcohol by hydration with glacial acetic acid and 

 sulphuric acid failed and led back again to ocimene. 



Pinene. Concerning this terpene, Kondakow 1 ) gives a historical 

 retrospect of the development of the formulae drawn up for pinene 

 by Kannonikow, Wallach, Bredt, v. Baeyer and Wagner. 

 But while the structure of pinene itself has now become clear, this 

 is not yet the case with regard to the reaction-mechanism of the 

 principal conversions. A distinction must be made whether the 

 reaction occurs with the double-linking, or with the diagonal linking 

 of pinene. Thus, in the oxidation into pinene glycol and into 

 pinol, the latter appears to be split asunder and the double linking 

 to remain intact. In view of the spatial arrangement of the pinene 

 molecule, a direct conversion from the glycol to pinol with loss of water 

 might be accepted. On the other hand, in the treatment with acids, 

 in attaching HC1, etc., the bridge linking remains intact, and the 

 reactions takes place with the double linking. Kondakow includes 

 in this the formation of pinene hydrochloride and its isomerides, of 

 pinene dibromide, and also of terpineol, whereby S0 4 H 2 is said to 

 attach itself to the double linking, with erection (Kondakow says 

 not quite correctly "splitting -off") of the isopropyl-group, and in which 

 subsequently the ester and finally the alcohol itself is formed 2 ). Accord- 

 ing to Kondakow, the formation of the terpineol derivatives occurring 

 naturally results in a similar manner. The occurrence of isomeric 

 additional compounds is explained partly by re-grouping of the addi- 

 tive atom-arrangements in the finished product, and partly by their 

 entrance at various places in the picean ring. This appears to be 

 proved by the behaviour of the as yet little examined alcohol pinanol 

 [pino campheol] 3 ). 



With regard to the behaviour of pinene while being brominated, 

 and the occurrence of cyclene, the opinions have not yet become 



*) Chem. Ztg. 29 (1905), 1225. 



2 ) Kondakow's ideas about the reaction-process are, in our opinion, not 

 very clearly expressed. 



3 ) Whether, as Kondakow supposes, a migration of the carbon linkbgs in 

 the HC1 addition product of this alcohol, with formation of bornyl chloride and 

 Fenchyl chloride, actually takes place, will have to be proved by the further 

 experiments which are announced. 



