21G MM. Kekule and Linncmann on Bisulphide of Acetyle. 



could not be quite freed. In this condition it was quite soluble 

 in acetic acid; but when dried, it could be broken into vitreous 

 fragments, and was no longer soluble in that reagent. 



By employing a more dilute solution of the silk and the appli- 

 cation of heat, the solution was obtained quite clear; all the 

 chloride of zinc could then be separated by the dialyser, and an 

 insipid colourless liquid was finally obtained, which on evapora- 

 tion left a golden brittle varnish. 



Kekule and Linnemann* have investigated the action of iodine 

 on some organic sulphur- compounds. 



When iodine is added to a solution of sodium-mercaptan, a 

 brisk action takes place, the colour of the iodine disappears, and 

 an oily layer separates on the surface which has all the properties 

 of bisulphide of ethyle. The reaction may be thus expressed ; — 



2G *Nl} S+2I=2NaI + SS} S9 - 



Sodium- Bisulphide 



mercaptau. of ethyle. 



The action of iodine on the thiacetates of sodium, potassium, 

 and barium was also investigated. The reaction is in all cases the 

 same ; an iodide of the metal is formed and bisulphide of acetylc, 

 thus 



2G2H3 m} s+2I=3MI+ §h3©} s5 - 



The raw product from this reaction contains some free sulphur, 

 resulting from an action of water on the bisulphide. It is purified 

 by washing with water, drying over CaCl, and filtering. A pro- 

 duct is thus obtained which, in winter, gradually solidifies to a 

 crystalline mass. This substance still contains free sulphur; it 

 is accordingly exposed to a temperature of 15°, upon which it 

 partially crystallizes ; the liquid is poured off from the crystals, 

 which are then melted and again allowed to crystallize, and the 

 process is repeated several times. Finally, the crystals are dissolved 

 in a small quantity of bisulphide of carbon, the solution cooled, 

 and a crystal of bisulphide of acetyle added, on which large 

 colourless transparent crystals gradually form. 



Pure bisulphide of acetyle melts at 20°; it has a peculiar, very 

 slightly hepatic odour. It is insoluble in water, but readily so in 

 alcohol, ether, and bisulphide of carbon. It is decomposed by 

 water, with formation of thiacetic acid and separation of free 

 sulphur. It is decomposed with violence by strong nitric acid. 

 It is also decomposed by heat. When distilled, thiacetic acid 

 passes over at 93°, {he temperature gradually rises to 160°; the 



* Liebig's Annalen, September 1862. 



