— 198 — 



1-camphor. Synthetic borneol from d-pinene is therefore a mixture of 

 d-borneol and l-?so-borneol, and at least one of these constituents is 

 accompanied by its optical antipode. Experiments made with French 

 turpentine oil (1-pinene) as crude material gave an analogous result, the 

 borneol thus obtained being composed of 1-borneol and d-?wborneol, ac- 

 companied by small proportions of their optical isomerides. The purpose 

 of the investigation, i. e. to prepare synthetically active d- or 1-camphor with 

 a high rotation, had been attained. By slightly modifying the conditions 

 of his experiments, for instance by keeping the temperature of the reaction 

 down to a still lower point, Darmois hopes to succeed in preparing a 

 camphor of the same rotatory power as the natural product. 



On the behaviour of camphor when exposed to light, see p. 167. 



Fenchone. Bouveault and Levallois' 1 ) paper on the constitution of 

 fenchone, which was published some time ago in the Comptes rendus. has 

 recently also appeared elsewhere with full experimental details 2 ). 



On the behaviour of fenchone when exposed to light, see p. 168. 



Thujone. In a paper read before the London Chemical Society, 

 D. Thomson 3 ) describes a series of derivatives of /^-thujone (tanacetone). 

 When this substance is treated with magnesium methyl iodide, two 

 tertiary homothujyl alcohols 



C 3 H 7 c^ /CH 3 



CH 3 OH 



are formed, one of which is solid (m. p. 84; [«] D — 30,5°), while the other 

 appears in the form of a liquid boiling at 204°; [«] D + 35°. The cyclo- 

 propane ring of these alcohols is not disrupted by cold 5°/o sulphuric 

 acid. The author also states that «-thujaketonic acid 



C 3 H 7 <^ x COCH 3 



is decomposed by being boiled with 20°/o hydrochloric acid, the reaction 

 giving rise to an unsaturated hydrocarbon, of which the odour and the b. p. 

 agree with those of dihydro-pseudocumene. Oxidation of «-thujaketonic acid 

 yields «-thujadicarboxylic acid, an acid which remains stable when boiled 



x ) Compt. rend. 146 (1908), 180; Report April 1908, 189. 



2 ) Bull. Soc. chim. IV. 7 (1910), 542, 683, 736, 807. 



5 ) Proceed, chem. Soc. 26 (1910), 177; Journ. chem. Soc. 97 (1910), 1502. 



