1866.] 



On the Action of Trichloride of Phosphorus, 



55 



I. " On tlie Action of Trichloride of Phosphorus on the Salts of 

 the Aromatic Monamines." ByA. W. Hofmann^ LL.D._, F.E.S., 

 &c. Received March 3, 1866. 



The starting-point of the following experiments was an accidental obser= 

 vation. Whilst investigating the chlorine-, bromine-, and nitro-derivatives 

 of aniline, I had prepared a large quantity of phenylacetamide by the action 

 of chloride of acetyl on-aniHne. From the hydrochlorate of aniline, abun- 

 dantly produced as a by-product in this reaction, the anihne was recovered 

 by treating the mother-liquors with hydrate of sodium. During the distil- 

 lation, after the greater part of the aniline had passed over and collected in 

 the receiver, a tenacious oily fluid began to come over, adhering to the tube 

 of the condenser and gradually becoming a crystalline mass. It was easily 

 purified by washing with cold, and crystallization from hot alcohol. 



Beautiful white leafy crystals were thus obtained, fusible at 137°, and 

 volatile without decomposition at a temperature beyond the range of the 

 mercury-thermometer. These crystals are almost insoluble in water, diffi-. 

 cultly soluble in cold, but soluble in hot alcohol, and also soluble in ether. 

 The solutions are neutral. 



In acids the crystals are also easily soluble ; an allcali precipitates the 

 original substance unaltered from the solutions. The hydrochloric-acid 

 sohition yields, with tetrachloride of platinum, a difficultly soluble crystal- 

 line precipitate. The new substance thus exhibits the deportment of a 

 well-characterized base. Its composition was readily determined by com- 

 bustion with oxide of copper, the analytical results pointing unequivocally 

 to the formula 



C, IL N 



as the simplest atomic expression for the body. But the whole beha- 

 viour of the substance, and more especially its transformation, by means 

 of concentrated sulphuric acid, into aniline and acetic acid, leave no doubt 

 that the above expression must be doubled, and that the new base is repre- 

 sented by the formula 



This formula was confirmed by the analysis of the platinum-salt already 

 mentioned, and that of the nitrate which separates from the solution as 

 an oily fluid, gradually changing to a beautiful crystaUine compound ; the 

 former contains 



2(C,, H,,N, HCl),Pt*Cl„ 



the latter 



C,,H,,N„IIN03. 



Whence is this body derived ? and how is its formula to be interpreted? 

 An answer to these questions was furnished by examining the chloride of 

 acetyl employed in preparing the phenylacetamide. When on distilling 

 the chloride the principal product had passed over, the thermometer gra- 



* Ptc=198. 



