286 



XIV. "Researches on the Phosphorus-Bases." No. XIII. 

 Sulphuretted Derivatives of Triethylphosphine. By A. W. 

 HOFMANN, LL.D., F.R.S. Received May 24, 1861. 



In the former Notes of my researches on the phosphorus-bases, 1 

 have repeatedly alluded to the beautiful red crystals, 



C 7 H 15 PS 2 =(C 2 H 5 ) 3 P,CS 2 , 



which are formed by the action of disulphide of carbon on triethyl- 

 phosphine. I have pointed out that the facility and rapidity with 

 which they are formed, render disulphide of carbon a most valuable 

 reagent for the phosphorus-bases (trimethylphosphine exhibiting a 

 perfectly similar deportment), since neither the monarsines nor the 

 monostibines are in any way affected by this substance. 



On the other hand, triethylphosphine may be employed with the 

 greatest advantage as a test for disulphide of carbon. There is, in 

 fact, no test for this substance which in delicacy could be compared 

 with triethylphosphine. By its aid the presence of the disulphide 

 in the most volatile fractions of coal-tar-benzol is readily proved ; 

 even the exceedingly small quantity of disulphide of carbon diffused 

 in the most carefully purified coal-gas, may, as I have shown already 

 in another place*, be recogized without any difficulty. 



In describing in a previous Note the formation and composition of 

 the disulphide-of-carbon-compound, I have already mentioned the 

 peculiar transformation which this substance suffers under the in- 

 fluence of water, being converted under these circumstances into the 

 sulphide of triethylphosphine. 



I have of late minutely examined this remarkable reaction. 



The transformation is most conveniently studied by digesting the 

 disulphide-of-carbon-compound with water in sealed tubes. After 

 three or four days' exposure to 100, the red crystals have disappeared, 

 being replaced by the slender crystals of the sulphide. The latter 

 compound is accompanied by several other products, the nature of 

 which varies according to the duration of the reaction. In the first 

 stages of the process considerable quantities of disulphide of carbon 

 are separated, which in the latter stages may be traced in its products 

 of decomposition, carbonic acid and sulphuretted hydrogen. The 



* Quarterly Journal of the Chemical Society, vol. xiii. p. 87. 



