490 
DE. A. W. 1IOFMAA3 OX THE PHOSPHOEL'S-BASES. 
have described in one of the previous paragraphs of this paper, the idea suggested itself 
that the bromide of vinyl-triethylphosphonium might also be formed by the action of 
bromide of vinyl (0*2 H3 Br) on triethylphosphine : 
(C, p + c, H3 Br = [(C, H3) (C, H3)3 Pj Br. 
In performing the experiment, I had an opportunity of obsening the sluggishness 
of action of this bromide, often previously noticed in experimenting in the ammonium- 
series. When gaseous bromide of \inyl is passed through triethylphosphine, not a trace 
of it is fixed by the phosphorus-base. Triethylphosphine may be distilled in an atmo- 
sphere of the bromine-compound without under’gomg any alteration. Bromide of rinvL 
freed from every trace of adhering dibromide of ethylene by repeated distillation at a 
low temperature, and subsequent washing with lukewarm water, was therefore enclosed, 
together with triethylphosphine, in a strong glass tube. Xo change was perceptible 
after two days’ digestion at 100°; and it was only on the third day that a thin layer of 
viscid matter began to separate at the bottom of the tube. The digestion was then con- 
tinued at a higher temperature ; and after the mixture had been exposed for three days 
longer to a temperature varying from 160° to 180°, about half the fluid was found to be 
converted into a solid mass, while a limpid liquid floated on the top. On opening the 
tube, cooling it well at the time, the liquid effervesced strongly, and a gas escaped which 
burned with a green-edged flame, and appeared to consist, partly at all events, of the 
vapour of unaltered bromide of vinyl. In subsequent repetitions of the experiment, it 
frequently happened that the tubes were shattered by the sudden expansion of the com- 
pressed gas ; hence probably permanent gases are formed in the reaction. The liquid 
decanted from the solid proved to be a mixture of undecomposed bromide of vinyl with 
free phosphorus-base ; the solid mass was found to consist of several bodies. On dis- 
solving it in water, a rather small quantity of a sparingly soluble, beautifully crystalline, 
nacreous salt separated out, the composition of which is at present undetermined. By 
treatment of the filtered solution with oxide of silver, a strongly alkaline liquid was pro- 
duced, which, when neutralized with hydrochloric acid and precipitated with dichloride 
of platinum, gave at once the amorphous yellow platinum-salt easily soluble in dilute 
hydrochloric acid. 
On analysis, this platinum-salt furnished the followmg results. Analyses I. and II. 
were made with the salt obtained by the action of bromide of rinyl on triethylphosphine. 
The platinum-determmation III. refers to a salt prepared with the product of the action 
of heat on the hydrated diphosphonium. 
I. 0’5717 ,grm. of platinum-salt gave 0*5211 grm. of carbonic acid and 0*2538 grm. of 
water. 
II. 0*7623 grm. of platinum-salt, decomposed with hydro sulphiuic acid, tSec., ga^’e 
0*2228 grm. of platinum. 
III. 0*6531 grm. of platinum-salt, analysed in the same manner, gave 0*1895 grm. of 
platinum. 
