V — 145 — 



In our Report of April 1912, p. 165, we mentioned a method devised 

 by Klimont and Neumann for determining a standard for the unsaturated 

 character of hydroaromatic compounds. G. O. Gaebel 1 ) has tested by this 

 method a series of bodies with double bonds and has found that peculi- 

 arities of a structural nature, such as the presence and position of highly 

 negative radicals, the. number of double bonds and steric conditions, 

 certainly play an important part, for which reasons the method is often 

 found wanting. 



C. Harries 2 ), in a recently-published communication, has expressed 

 the opinion that the so-called catalytic decomposition of ozone by soda 

 liquor and concentrated sulphuric acid depends in the first place upon 

 the destruction of oxozone (0 4 ). Harries, however, believed that the 

 ordinary 12 to 14 p. c. ozone contained comparatively little oxozone and 

 that liquefaction of the crude ozone was needed in order to accumulate 

 the oxozone content. More recent investigations have shown this assump- 

 tion to be incorrect, and Harries 3 ) now assumes that ordinary 11 to 14 p. c. 

 ozone, as prepared in parallel connected Berthelot-tubes at a tension of 

 about 8200 volts and a frequency of the alternating current of 100 second- 

 periods, consists to the extent of about one-third of oxozone. He assumes 

 this because soda liquor and concentrated sulphuric acid destroyed 

 4,7 p. c. out of 14 p. c. at 15 Z-hours' velocity, and 6,2 p. c. out of lip. c. 

 at 10 Z-hours' velocity. If this observation is correct, it follows that it 

 must be possible to obtain normal ozonides with washed ozone from all 

 the compounds which, up to the present, have yielded upon ozonisation 

 oxozonides or mixtures of 3 - and 4 - ozonides. As a matter of fact, 

 when 4,8 to 9,3 p. c. ozone was passed through a solution of pinene in 

 hexane, the ozonide Ci Hi 6 O 3 was separated out in the form of a solid 

 white mass. Terpineol in hexane solution also yielded a solid, white, 

 normal ozonide; from citronellal in hexane solution the normal ozonide 

 separated out in the form of a colourless oil. 



Hydrocarbons. 



By passing linalool vapour over active copper at 130 to 140°, 



»C. J. Enklaar 4 ) obtained a hydrocarbon Ci Hi6, which is probably identical 

 with myrcene: b. p. 62° (14 mm.), di 50 0,802, n D150 1,47. The same hydro- 

 carbon is generated when linalool is heated with phenyl zsocyanate. 

 Hydrogenation of the hydrocarbon with nickel and hydrogen at 130° 

 yields 2,6-dimethyloctane. 



*) Arch, der Pharm. 250 (1912), 72. 



2 ) Zeitschr. f. Elektrochemie 18 (1912), 130. 



3 ) Berl. Berichte 45 (1912), 936. 



*) Chern. Weekblad9 (1912), 68. Quoted from Chem. Zentralbl. 1912, I. 726. Also compare 

 Report October 1910, 187. 



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