486 
DE. A. ^Y. HOPMAXy OX THE PHOSPHOEUS-BASES. 
The theoretical platinum percentage of the compound 
[(C 2 H 3 )(C 2 H,) 3 P]C 1 , PtCl 2 
is 28T9. The formation of the \inyl-compound under these circumstances is easily 
explained. 
C, H, Br, + 2 [(C^ HJ., P] = [(C, H 3 )(C, H 3)3 P] Br + [(C^ B,}, H P] Br. 
The amount of vinyl-compound produced is but ver}' small in proportion to that of 
the other salts which are formed in the mutual action between tiiethylphosphine and 
dibromide of ethylene. 
Action of Heat upon the Hydrate of the Hiphosphonium. 
The hydrate, when submitted to the action of heat, undergoes a series of remarkable 
changes, which I have studied with lively interest. The decomposition commences at 
160°; on raising the temperature gradually to 250°, the whole of the hydrate passes 
over in the form of liquid and gaseous products. The liquid product consists of 
triethylphosphine and oxide of tiiethylphosphine ; the gas contams a considerable pro- 
portion of ethylene, which is readily characterized by its deportment uith bromine. 
This transformation may be represented by the following equation : — 
H‘)" = (C 3 Hj);, P + (C 3 Hj), P O + a H, + H, O. 
The succession of changes, however, through which the hydrate runs before it is 
broken up, shows unmistakeably that this equation can represent but one phase, ei'en of 
the final transformation of the diphosphonium-compound. The study of the inter- 
mediate changes presents unusual difficulties, and I confess at once that I have failed to 
solve the problem to my entire satisfaction. 
The experiments performed with a tdew of disentangling the intricacies of these 
reactions, will perhaps be better understood if I commence uith setting forth the ideas 
which I have ultimately formed of these metamorphoses, and then state the anahtical 
results which have assisted me in forming them. 
Under the influence of heat, the hydrate of the diphosphonium undergoes two prin- 
cipal transformations, which are accomplished side by side. A portion of this compound 
gives rise to the formation of oxide of triethylphosphine and hydrate of tetrethylphos- 
phonium, 
H4r(C,H3)6PJ'l 
H J 
the latter splitting ultimately into oxide of triethylphosphine and hydride of ethyl, 
[(C 2 H5)4 P]|q ^ p Q jj . 
a second portion is resolved into triethylphosphine and hydrate of oxethyl-triethyl- 
phosphonium, 
H4)"(C,H3)ePJ' 
H., 
o, = (c, 143)3 P + 
H 
O; 
,= (C,H3)3P0 + 
[(aH3),P] 
H 
O, 
