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XXXI. On the Direct Transformation of Chloriodide of Ethylene 

 into Glycol. By Maxwell Simpson, M.D., F.R.S.* 



CJOME years agof I discovered a compound having the compo- 

 sition C 9 II 4 " < | , which I called chloriodide of ethylene. 



With this body I have tried a great many experiments, in the 

 hope of being able, whilst retaining one of the metalloids in its 

 place, to substitute a monatomic radical, such as hydroxyl, cy- 

 anogen, &c, for the other. These experiments have all failed. 

 I have found that the metalloids in this compound always act in 

 concert, so that it is impossible to replace one of them by any 

 radical without at the same time replacing the other. One of 

 these experiments I will now describe, as it produced a definite 

 result. 



In the hope of forming a chloralcohol, I heated one molecule 

 of the chloriodide of ethylene with one molecule of moist oxide of 

 silver, expecting that the reaction would take place according to 

 the following equation : — 



C 2 II 4 " j j? 1 + ^' } 9 = C ~ II 4 CI . O H 4- Agl. 



]\Iy expectations, however, were not realized. Instead of a chlor- 

 alcohol 1 obtained cthylglycol as the product of the reaction, 

 both the metalloids having been replaced by hydroxyl: — 



C 2 II 4 '' { P+2(h S } 0)=C*H«' { [\ \\ +AgCl+AgI. 



Glycol. 



The experiment was performed in the following manner : — 

 Into a strong glass matrass with a Lone neck 1 introduced one 

 molecule of the chloriodide and one molecule of moist oxide of 

 silver. I then sealed the matrass and exposed it for twenty-four 

 hours to a temperature ranging between L60° and 200° C. At 

 the expiration of this time I opened the matrass and filtered its 

 contents. The filtered liquor, which was perfectly transparent 

 and colourless, was then subjected to distillation. As soon as 

 the water had passed over, the thermometer rose rapidly to 

 180° C. ; and between that temperature and 220° C. a consider- 

 able quantity of a syrupy liquid distilled over, which I recognized 

 to be glycol by the following properties : — It had a sweet taste, 

 it was soluble in water, it boiled between 195° and 200° C«, 

 and gave, when treated with hydriodic acid, iodide of ethylene. 

 The same results were obtained when one molecule of the chlor- 



* Communicated by the Author. 



t Proceedings of the Royal Society, vol. xii. p. 278. 



