o.")4 PROF. LETTS AND MR R. F. BLAKE ON 



It is remarkable that the phosphine should thus seize upon the oxygen of the 

 c;irboxyl group, and not upon the halogen. 



It is probable that another reaction occurs to a slight extent, viz.: — 



C 7 H 7 PH 2 + CH.,C1 - COOH = (C 7 H 7 )(CH,)PH,HC1 + CO , . 



This equation, at all events, accounts for the liberation of carbonic anhydride, and is 

 supported to a certain extent by the experiments which one of us has made on the action 

 of chloracetic acid on triethyl-phosphine, or rather upon that of heat upon the product.* 



Action of Bromacetic Acid upon Monobenzijl Phosphine. — We have not fully 

 investigated the nature of this action, but we found that when the two substances 

 were mixed, the bromacetic acid dissolved, and in a short time a. crystalline product 

 resulted. In about half an hour's time, however, an explosive decomposition of this 

 substance occurred spontaneously, torrents of hydrobromic acid coming off, and a viscous 

 liquid resulting, which was insoluble in water. We did not investigate the product, as 

 nearly all of it was shot out of the vessel in which the experiment was made when the 

 explosive action occurred. It is probable, we think, that a, product of addition is first 

 formed, which may then decompose in the following way : — 



7 H%P<^2-COOH = C , 7 H 7 \ >p _ CHCOOH + HBr 



Action of Chlorocarhonic Ether on Monobenzijl Phosphine. — When the two sub- 

 stances are sealed up together a reaction gradually occurs, and thin quadratic plates of 

 fair size are slowly deposited. On opening the tube pressure is observed. We could 

 not obtain the crystals in a sufficiently pure state for analysis. They were so deliquescent 

 that on attempting to dry them on filter-paper, they almost instantly deliquesced. They 

 dissolved in alcohol, ether, and benzol. Alcoholic chloride of platinum gave a yellow 

 slimy precipitate ; alcoholic corrosive sublimate, a, white amorphous precipitate, which 

 soon turned grey. On warming them with baryta solution, carbonate of barium was 

 precipitated. We think that these properties indicate that the substance is a product of 



addition — 



C 7 H 7 . /C00C 9 H-, 



H / X C1 . 



Hofm ann's " Dibenzyl " Phosphine. 



In his well-known researches on the phosphines, Hofmann has apparently shown 

 that when an alkyl haloid is heated with phosphonium iodide and oxide of zinc, 

 primary and secondary phosphines alone result ; whereas when an alcohol is heated 

 with iodide of phosphonium alone, tertiary and quaternary phosphines are formed 

 exclusively. Thus the two reactions arc complementary to each other. Among the 



* Letts, these Transactions, xxx. part 1, p. 285. 



