( 56fi ) 



compounds not looking fil for furtlier investigation. By cantious 

 treatment witli formic acid tlie difoi-mate was, however, readily 

 obtained (see p. 544). 



In order to convert this into the h3'drocarbon, a reaction was 

 applied which one of us had previonsly nsed for preparing allyl 

 alcohol from the diformate of glycerol, and which consists in heating 

 that compound with glycerol. 



And, indeed, a mixture of the diformate of divinyl glycol with 

 the glycol when heated slowly, first at 165^ and then gradually to 

 200"', evolves carbon dio.xide and a little carbon monoxide and yields 

 a distillate consisting of two layers, the upper one of which consists 

 of a hydrocarbon. 



The triformate of glycerol, like the diformate of divinyl glycol, 

 may be distilled without notable decomposition by heating it some- 

 what rapidly at the ordinary pressure. Recently' one of us (v. R.) found 

 however that it is decomposed b}' prolonged heating at a temperature 

 a little below the boiling point and it then yields the same decom- 

 position products as the diformate of glycerol. 



If now the diformate of s. divinyl glycol is heated at J 65^ and 

 the temperature allowed to rise very slowly, an evolution of gas is 

 observed and in the receiver is collected a liquid consisting of two 

 layers. The upper layer again consists of a h^-drocarbon identical 

 with the one cited aboxe. 



Probably, the simplest way to explain this reaclion is to assume 

 that the diformate contains a little monoformate which is decomposed 

 in the desired sense, with formation of water which in turn regene- 

 rates monoformate from liie diformate. Finally, a residue consisting 

 of glycol (respectively, polyglycols) is obtained and in the distillate 

 a little formic acid is found, besides water, whilst tiie gases evolved 

 consist of carbon dioxide and carbon monoxide. The last method 

 appears to give a better yield than the first one. 



The hydrocarbon formed is separated and distilled, the portion 

 distilling up to 95° being collected. It is then dried over a piece 

 of caustic potash, which also removes traces of formic acid and then 

 rectified a few times over metallic sodium. 



It then forms a colourless, strongly refracti\e liquid with a slight 

 pungent odour ; in contact with the air it appears to slowly oxidise. 

 Tlie boiling ])oint lies between 77°— 82°, the main traction boils 

 between 78*,5 — 80° (corr. ; pressure 766 m.ni.) 



The analysis and the vapour density ga\e \aluos leading to the 

 composition C, H^. 



For the physical constants of the main fraction was found ; 



