292 



obtained in this manner is obviously the dichloride of methylene-hex- 

 ethyldiphosphonium, 



[(0 H a Cl) (C, H s ) a P] Cl + (C, H s ) 3 P= [(C H 2 )" jg j^lT*- 



I have not succeeded in seizing the dichloride in a state fit for 

 analysis, since this compound cannot be brought in contact with 

 water without undergoing immediate decomposition; but I have 

 been able to trace the diatomic compound in its products of decom- 

 position. The solution of the dichloride is not precipitated by 

 dichloride of platinum, but, on evaporation, orange-yellow, well-deve- 

 loped octohedra are deposited, which are the platinum-salts of methyl- 

 trie thylphosphonium. The mother-liquor of the octohedra furnishes 

 the six-sided tables of the platinum-salt of triethylphosphine. 



The following equation represents the transformation of the di- 

 chloride of the diphosphonium under the influence of water, 



'[g*^ 



It is thus seen that the diatomic compounds of the methylene- 

 series undergo, even in the form of salts and at the common tempe- 

 rature, a change which in the ethylene-series is observed only with the 

 free bases and under the influence of a high temperature. When 

 hydrate of ethylene-hexethyldiphosphonium is heated, hydrate of 

 tetrethylphosphonium and oxide of triethylphosphine are prominent 

 among the products of decomposition, 



KC, H.HC, H 5)e pj j _KC, HO. P] j 0+ (Ct Hs)3 pa 



Di-iodide of methylene (obtained by the action of heat upon iodo- 

 form) imitates in every respect the deportment of the chlorine-com- 

 pound with triethylphosphine. The dibromide, on the other hand, 

 which is formed by the action of bromine upon the di-iodide, acts 

 in a perfectly different manner. I propose to examine this reaction 

 in a subsequent communication. 



The action of tetrachloride of carbon, C C1 4 , on triethylphosphine 

 gives rise to changes resembling in many respects the transformations 

 which I have described. On submitting tetrachloride of carbon to 

 the action of triethylphosphine, I was surprised to find that the 

 chloride, which resists with such pertinacity the influence of the 



