Tetrethylphosphonium and their Decomposition by Heat. 201 



phosphine, and some oxide of triethylphosphine were pro- 

 duced. Probably also a gaseous hydrocarbon was evolved. 

 Mixed with the' triethylphosphine and insoluble either in 

 water or hydrochloric acid were a few drops of a liquid smell- 

 ing of acetonitrile, and evolving ammonia when boiled with 

 caustic potash. The production of free phosphine and aceto- 

 nitrile indicate that part of the cyanide at least decomposes 

 according to the equation 



(C 2 H 5 ) 8 P<§f 6 =(0 2 H 5 ) 3 + C 2 H 5 CN. 



The decomposition, however, is complex, owing to the high 

 temperature at which it occurs. 



We may mention that the cyanide when heated with cold 

 caustic-potash solution is not changed, and appears to be 

 quite insoluble if the solution is strong. On warming the 

 mixture a copious evolution of inflammable gas occurs, and 

 the whole of the cyanide decomposes according to the 

 equation. 



(C 2 H 5 ) 3 P<^ 5 + KOH=(C 2 H 5 ) 3 PO + KCN + C 2 H 6 . 



The action of heat on the iodide was also investigated: it 

 first fuses, but does not suffer any further change until the 

 temperature has risen above the boiling-point of mercury. 

 It then turns brown and splits up into hydriodic acid, free 

 phosphorus, and gaseous products, and a charred residue 

 remains. 



The decomposition is therefore complex, and cannot be ex- 

 pressed by an equation. 



Although the iodide is not attacked by an aqueous solution 

 of caustic potash, yet when boiled with a concentrated alco- 

 holic solution it slowly decomposes in the same manner as 

 the cyanide. 



Action of Heat on the Chloride of Tetrethylphosphonium. 



After finding that neither the cyanide nor the iodide of 

 the phosphonium when heated yield triethylphosphine in large 

 quantities, it was hardly thought probable that by the action 

 of heat on the chloride the tertiary base would be produced. 

 The results obtained were, however, of the most unexpected 

 nature. 13*5 grins, of the phosphonium iodide were con- 

 verted first into hydrate, and then, by careful addition of 

 hydrochloric acid till the solution was neutral, into the chlo- 

 ride. The solution was evaporated on the water-bath until 



