186 PROFESSOR LETTS AND N. COLLIE ON THE 
account of the uncertainty of the reaction, the frequent explosions, and the 
great difficulties in separating the resulting phosphines from each other,—“ not 
to speak of the difficulty of obtaining the phosphide of sodium fit for the 
reaction.” 
It seemed to us, however, that in phosphide of sodium an admirable reagent 
was at hand for the preparation of tertiary phosphines—provided only, to quote 
again Hormann’s words, that it can be obtained in a state “fit for the 
reaction.” 
This conclusion has been borne out by our experiments. With proper 
precaution, phosphide of sodium may be obtained in any quantity, and in a 
perfectly safe condition. It reacts with haloid ethers in a perfectly smooth 
manner, nor have we ever had an explosion, nor remarked the production of 
explosive bodies. 
Our first experiments were made with iodide of ethyl. The reaction occurs 
at ordinary temperatures with ease, the iodide of ethyl boils violently, and the 
chief product of the reaction appears to be the iodide of tetrethyl-phosphonium. 
We have not as yet, however, brought these experiments to a conclusion, 
because of the difficulties which we experienced in separating the phosphines 
and phosphonium salt from the iodide of sodium produced along with them in 
the reaction. 
Our next experiments were made in the benzyl series, which we chose 
partly because neither tribenzyl-phosphine nor tetrabenzyl-phosphonium salts 
have hitherto been obtained, and partly because no deliquescent or volatile 
bodies were likely to be formed, thus rendering the investigation free from 
those difficulties which cause experiments in the methyl and ethyl series to be 
so troublesome and laborious. To these reasons for our choice of benzyl must 
be added its similarity to fatty radicals and the well-known ease with which its 
compounds react. 
Before proceeding to describe our experiments on the preparation of phos- 
phide of sodium, and on its action on chloride of benzyl, we consider it 
necessary to give a short account of Hormann’s researches on monobenzyl- 
and dibenzyl-phosphine, which we believe to be the only ones that have been 
made on benzyl-phosphines. 
Benzyl-Phosphines. 
The following is an abstract of Hormann’s paper on “ Aromatic Phos- 
phines” :*— 
He was induced to experiment on the aromatic series, in consequence of the 
readiness with which, by the use of iodide of phosphonium, he had obtained 
* Hormann, Ber. d. deutsch. chem, Ges., iv. p. 100. 
