BENZYL PHOSPHINES AND THEIR DERIVATIVES. 585 



Thus- 





Calculated for 





C 14 H 15 PO 





(Cu 



H l5 P0) 2 CdI 2 



... 







13-56 

 30-85 



7304 







4068 



6-52 







363 



13-48 







750 



Cadmium, 

 Iodine, 

 Carbon, . 

 Hydrogen, 

 Phosphorus, 



This would be the formula of an oxide of dibenzyl phosphine, 



C 7 H 7 . 



C 7 H 7 ->P = 0, 

 H' 



a substanee which would probably not have acid properties, and which would easily be 

 oxidised to dibenzyl phosphinic acid. 



We may mention that quite accidentally we discovered that when the high boiling 

 residues obtained in fractionating the primary phosphine are allowed to oxidise spon- 

 taneously, the crystalline oil is produced; and as we have shown that the secondary 

 phosphine is formed in the sealed tube reaction, we think it quite possible that the 

 crystalline oil is its oxide. 



No such body has been obtained hitherto, but then the products of the spontaneous 

 oxidation of secondary phosphines have scarcely if at all been investigated. The point is 

 one of some interest, and we intend to submit it to enquiry. 



E. " Insoluble Crystalline Body." — We obtained this substance in some of our later 

 experiments. It remained undissolved when the oily mass containing the secondary and 

 tertiary phosphine was treated with ether, accompanied by oxide of tribenzyl phosphine. 

 It was separated from this latter body by boiling with alcohol, in which it was 

 insoluble. 



We also found it in the ethereal solution of the phosphines, from which it was slowly 

 deposited spontaneously. 



It was insoluble in water, alcohol, and ether, but sparingly soluble in boiling glacial 

 acetic acid, from which it was deposited on cooling in colourless needles of characteristic 

 crooked form. Twice recrystallised from acetic acid, its corrected melting point was 

 found to be 27 6° -27 7°. Two analyses were made, one a combustion with oxide of copper 

 and chromate of lead, the other a combustion with pure oxide of copper, in order to 

 determine the phosphorus as well as carbon and hydrogen. 



Analysis. 



(l) Combustion with oxide of copper and chromate of lead. 



( 0-6355 C0 2 = 0-173318 C = 75-75 per cent. 

 0-^88 gave j . 136() H Q = . 015in H = 6 . 6Q : 



