M, Wurtz on Dioxy ethylene. 23 



Acetylene is not an isolated substance, but presents a starting- 

 point for the formation of other' bodies. Berthelot has shown 

 that by simple addition of hydrogen it can be changed into 

 defiant gas ; by means of olefiant gas, alcohol can be formed, 

 and thus a commencement made with the chain of compounds 

 which constitute organic chemistry. To all syntheses and pro- 

 gressive formations, that of acetylene furnishes the first step. 



In continuation of his researches on oxide of ethylene, Wurtz* 



tried the action of bromine on this substance. When oxide of 



ethylene was mixed with a suitable quantity of bromine, and the 



mixture kept cool, it was transformed into a mass of red crystals 



impregnated by a thick red mother-liquor. This was poured off 



and the crystals pressed between porous earthen plates. These 



crystals melt at 65° to a deep-red liquid, which boils at 95°, 



emitting an orange vapour, which on condensing reproduces the 



liquid and the red crystals. The crystals are insoluble in water, 



but dissolve in alcohol and in ether. The composition of the 



£ 2 H 4 01 

 crystals is expressed by the formula p2Tj4ri f Br 2 , — an instance 



of the simple addition of bromine to an oxidized body, the mole- 

 cule oxide of ethylene being doubled in combining. The bro- 

 mine is but loosely combined, and may readily be removed either 

 by sulphuretted hydrogen or metals, of which the most conve- 

 nient is mercury. The body formed by this reaction is a colour- 

 less liquid, with a feeble but pleasant odour. At a low tempe- 

 rature, it solidifies to a crystalline mass, which melts at -f- 9°. It 

 boils at 102°. Analysis and a determination of the vapour-den- 



f G 2 H 4 

 sity showed that its composition is € 4 H 8 2 = -j n2u4Q> ft ^ s 



oxide of ethylene doubled, or dioxy ethylene. It is an isomer of 

 the compound of aldehyde and oxide of ethylene discovered by 

 Wurtz, and may probably be regarded as the ether of diethyl- 

 enic alcohol, 



€ 2 H 4 1 



£2H 4 lo 3 -H 2 = € 4 H 8 2 . 



H 



2 



It is completely soluble in alcohol, ether, and water. It com- 

 bines with difficulty with anhydrous acetic acid. 



Wurtz placed an aqueous solution of oxide of ethylene in a 

 cooled vessel containing sodium-amalgam. On the following 

 morning the aqueous alkaline liquid was distilled, and the distil- 

 late rectified over carbonate of potash. It had the properties and 



* Comptes Rendus, February 10, 1862. 



