1868.] Dr. Hofmann on the Mustard Oil of the Ethyl Series. 257 



but diiFer from the ethylsulphocarbamate by their insolubility in water. 

 Hydrochloric acid dissolves them ; the solution yields, with perchloride of 

 platinum, a light-yellow precipitate. The new substance is diethylsul- 

 phocarbamide or sulphuretted diethylurea, the formation of which is repre- 

 sented by the following equation : — 



[(C S) " (C,H,) HN] 1 g_H 1 g , 1 N 



On gently heating a mixture of diethylsulphocarbamide with anhy- 

 drous phosphoric acid, pungent vapours are evolved, which are con- 

 densed to a yellowish liquid possessing in a remarkable manner the odour 

 of mustard oil. "When rectified, this liquid becomes colourless ; it boils 

 constantly at 134°, and has the same composition as the sulphocyanide of 

 ethyl which is formed by the action of a metallic sulphocyanide upon 

 sulphethylate of potassium. The new substance is formed by the sepa- 

 ration from the diethylsulphocarbamide of one molecule of ethylamine, 

 which unites with the phosphoric acid. 



ss|:x}n.=(oa)},,(cs)^^},. 



In its properties, the new compound essentially differs from the known 

 sulphocyanic ethylether. The boiling-point of the latter is 147°; the new 

 substance therefore boils 13° lower than the old one. The powerfully irri- 

 tating odour of the new ether is absolutely different from that of the 

 ordinary sulphocyanic ether, which, though by no means agreeable, exerts 

 no marked action either upon nose or eyes. 



By far the most characteristic feature of the new compound, however, 

 is the facility with which it acts upon ammonia and its derivatives. Dis- 

 solved in alcoholic ammonia and digested for a few hours at 100°, the ether 

 is converted into ethyhulphocarhamide or sxdphuretted ethyl-urea. 



(aiy}N + H3N=(CA)HlN,. 



'2 > 



with methylamine a mixed urea is formed, 



(C.A)}^+ I N = (CH,)(CA) 



Ethylamine produces the dietliylated compound which has served in 

 the preparation of the ether ; aniline, lastly, gives rise to the formation of 

 a mixed urea of the fatty and aromatic series. 



(C S)" 1 , 



C.H, (CS)" 

 N+ H In = (C„H,)(C,HJ^N, 

 li H. 



