444 
DE. A. W. HOFMAXX OX THE PHOSPHOEUS-BASES. 
represented by the equation 
C N ■] 
H 
S + 2 [(C^ H5)3 P] + jj ^ O = (<^2 ^ 5)3 P S + 
H 
O + H C X. 
I have not been able to trace directly the hydrocyanic acid which figures in this 
equation, but this acid appears unmistakeably in its products of decomposition. The 
brown substance which accompanies the sulphide of triethylphosphine and the hydrate 
of tetrethylphosphonium is rich in nitrogen ; boiled for some time with hydrochloiic 
acid, it yields abundance of chloride of ammonium. In fact, it was on account of the 
presence of ammonia among the products of the reaction, that it became necessary to pre- 
cipitate the tetrethylphosphonium in the first place in the form of the gold-compound. 
I have likewise examined the behaviour of disulphocyanate of ethylene with triethyl- 
phosphine. The reaction takes place ttfith energy at ordinary temperatiu-es. TMien 
triethylphosphine is poured into a concentrated alcoholic solution of sulphocyanate of 
ethylene, the liquid immediately solidifies to a dazzling white ciystaUine mass of sul- 
phide of triethylphosphine. It deserves to be noticed that the same decomposition 
takes place also when the substances are allowed to react in the presence of anhydrous 
ether. The transformation which the sulphocyanate of ethylene undergoes under the 
infiuence of triethylphosphine is perfectly analogous to the change of the ethyl-compoimd 
when submitted to the same agent. Instead of a derivative of tetrethylphosphonium. 
the sulphocyanate of ethylene produces the cyanide of a diatomic metal, of ethylene- 
]iexeth,yl-di])liospJionium. 
(c,h')'1®^ + ^KC2H5)3P] 
2 [(C 3 Hj), P S] + (G, HJ' I I ]’'(C y),. 
-v 
Sulphocyanate 
of ethylene. 
Triethylphos- 
phine. 
■v" 
L. 
V_ 
Sulphide of 
triethylphos- 
phine. 
Dicyanide of ethylene-hex- 
ethyl-dipliosphonium. 
Owing to the low temperature at which the reaction is accomplished, the hydrocyanic 
acid is not changed in this case, and may be recognized without ditficulty by the ordi- 
nary reagents. The diphosphonium, which is simultaneously formed, was traced as 
platinum-salt, exactly in the same manner as the tetrethylphosphonium in the process 
previously mentioned. The product of the reaction, freed as far as possible from the 
sulphide by repeated evaporation and ultimately by treatment with ether, was preci- 
pitated by dichloride of platinum. The dingy platinum-salt was purified by treatment 
with sulphuretted hydrogen and reprecipitation. Eepeatedly treated in this manner, it 
assumed the character of a pure compound. 
0-2745 grm. of this salt gave 0-0804 gnu. =29-29 per cent, of platinum. 
The formula 
(C.H5)3PT' 
Cri,2PtCI, 
requires 29-27 per cent, of platinum. Since I shall have to give a detailed account of 
