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UNIVERSITY OP COLORADO STUDIES 



contains a benzene rest having all its central bonds intact. Thus, 

 for example, it was not possible to obtain the compounds in the cases 

 of pyridine, isoquinoline, and oxyquinoline. In the case of paratolu- 

 quinoline, one would expect, however, that the reaction would take 

 place, and this was indeed found to be true, since, as will be shown in 

 the experimental part, a sulphur body was obtained which was an 

 exact analogue to those obtained by Edinger, and in which the methyl 

 group was retained. In the light of the previous researches, the 

 following formula would be given to this body: — 



The strange fact here also developed that, by the analysis of the 

 compound, in spite of its careful purification by several recrystalliza- 

 tions, a too high percentage of hydrogen to conform to the above 

 formula was found. The possibility had then to be taken into 

 account that an addition of hydrogen in the course of the reaction 

 might have taken place. All experiments calculated to show such 

 an addition of hydrogen in the quinoline molecule were fruitless. It 

 finally became necessary therefore to consider the assumption that an 

 addition of hydrogen had taken place on the sulphur atoms and that 

 consequently, in these compounds, sulphur is tetravalent and not 

 divalent, as heretofore assumed. The most remarkable examples of 

 tetrav alent sulphur in organic compounds are the sulphur bases 

 E.3SOH, all of which show an alkaline reaction. Kehrman* and 

 Werner have also lately noticed organic compounds in which sul- 

 phur shows basic properties. The question therefore came into the 



(1 ) Berliner Berichte. 34. 4172. 



(2) Berliner Berichte. 34. 3311. 



