244 Royal Society : — 



pounds, however concentrated. But on adding the anhydrous oxide 

 to a concentrated solution of dichloride of platinum in absolute 

 alcohol, a crystalline platinum-compound is deposited after a few 

 moments. This compound is exceedingly soluble in water, easily 

 soluble in alcohol, insoluble in ether. On adding ether to the 

 alcoholic solution, the salt is precipitated, although with difficulty, 

 in the crystalline state. The alcoholic solution, when evaporating 

 spontaneously, yields beautiful hexagonal plates of the monoclinic 

 system, frequently of very considerable dimensions. The crystals 

 have the rather complex formula 



C 24 H M P 4 3 Pt, Cl e = 3[(C 2 H 5 ) 8 PO] + (C 2 H 5 ) 3 PC1 2 , 2Pt Cl 2 . 



On mixing the concentrated solution of the oxide with trichloride 

 of gold, a deep yellow oil is separated, which crystallizes with diffi- 

 culty after considerable standing. This compound is exceedingly 

 soluble in water and in alcohol. When the aqueous solution is 

 heated, the gold is reduced ; the transformation which the oxide of 

 triethylphosphine undergoes in this reaction is not examined. 



Chloride of tin forms likewise an oily compound with the oxide : 

 I have not succeeded in crystallizing this compound. 



Chloride of mercury is without any action on oxide of triethyl- 

 phosphine. 



Oxychloride of Triethylphosphine. — On passing a current of dry 

 hydrochloric acid through a layer of oxide of triethylphosphine 

 which is fused in a U-shaped tube surrounded by boiling water, 

 brilliant crystals are soon deposited. These crystals disappear, how- 

 ever, rapidly, the compound formed in the commencement of the 

 reaction uniting with an excess of hydrochloric acid. The viscous 

 liquid which ultimately remains behind, when heated loses the excess 

 of hydrochloric acid, leaving an exceedingly deliquescent crystalline 

 mass, very soluble in alcohol, insoluble in ether. 



For analysis, the new compound was washed with absolute ether 

 and dried over sulphuric acid in vacuo, either at the common tem- 

 perature or at 40°. Three chlorine-determinations in specimens of 

 different preparations, which, owing to the extraordinary avidity of 

 this compound for moisture, exhibit greater discrepancies than are 

 generally observed in experiments of this description, lead to the 

 f jrmula q^ h q p Cl - ^ H ^ POj ^ jy g p^ 



The dichloride of triethylphosphine cannot be formed by the action 

 of hydrochloric acid upon the oxide. 



The oxychloride exhibits with other compounds the deportment 

 of the oxide. It furnishes with dichloride of platinum the same 

 platinum-salt which is obtained with the oxide. In a similar man- 

 ner it gives with iodide of zinc the iodide of zinc-compound of the 

 oxide previously described. Only once — under conditions not sharply 

 enough observed at the time, and which I was afterwards unable 

 to reproduce in repeated experiments — a compound of the oxy- 

 chloride with iodide of zinc was formed. This substance, readily 

 soluble in water and alcohol, crystallized from the latter solvent in 

 beautiful colourless, transparent octahedra of the composition 

 C 12 H 30 P 2 O Cl 2 Zn 2 I 2 =(C 2 H 5 ) 3 PO, (C 2 U.) t PCI, 2ZnI. 



