1863.] 



J)r. Hofmann on Aniline-blue. 



11 



Free Base, — The separation of the base from the hydrochlorate presents 

 no difficulty. This salt dissolves in alcoholic ammonia, giving rise to a 

 wine-yellow solution. This liquid contains the base in the free state, 

 together with chloride of ammonium. On ebullition the blue colour re- 

 appears, the salt being reproduced with evolution of ammonia. Addition 

 of water, on the other hand, produces a white or greyish precipitate, con- 

 sisting of triphenylic rosaniline. The best mode of procuring this com- 

 pound in a state fit for analysis is to pour the concentrated solution of the 

 hydrochlorate in ammoniacal alcohol into water, when the base separates 

 as a curdy mass which soon collects upon the surface of the liquid. 

 During the process of washing, and especially of drying, even in vacuo, 

 the greyish powder gradually assumes a blue tint. The vacuum-dry sub- 

 stance, when exposed to 100°, assumes a deep brown colour, which it retains 

 on cooling ; at 100° it slightly fuses, but does not change weight. 



Triphenylic rosaniline shows a tendency to crystallize, but hitherto I have 

 not been able to obtain it in distinct crystals. The solution in alcohol and 

 also in ether (which dissolves the base with the greatest facility) have, 

 even on spontaneous evaporation, deposited the base in the form of an 

 almost amorphous residue. 



Analysis assigns to this base the composition which corresponds to that 

 of the hydrochlorate previously examined, namely 



C33 H33 N3 0=C,„ H,. (Ce H,)3 N3, H, O. 

 Triphenylic rosaniline is thus seen to separate from its saline combinations 

 in the state of hydrate, exactly like rosaniline itself. 



I have endeavoured to obtain further confirmation of these results by the 

 analysis of several salts of triphenylic rosaniline. These salts were inva- 

 riably prepared by treatment of the free base with the free acids. They 

 resemble in their properties the hydrochlorate — so much so, indeed, that 

 they could not possibly be distinguished without analysis. The nitrate 

 is perhaps a little more, the sulphate a little less soluble in alcohol than 

 the hydrochlorate. The following salts were submitted to analysis : — 



Hydrohr ornate. 

 C33 H33 N3 Br =C,o H,3 (Ce H,)3 N3, HBr. 



Hydriodate. 

 C33H3,N3l =C,,H,3(C,H,)3N3,HI. 



N^'itvate m 



C„H3,N,03 =C,„H,,(C3H,)3N3,HN03. 

 Sulphate. 



C TT N SO —^20 (Cg 115)3 Na"! HI 



-1^64 ^^C H,3 (Ce HJ3 N3 / H / 



Rosaniline, it will be remembered, forms, in addition to its ordinary 

 monatomic compomids, a series of triatomic salts, which are more soluble 

 and comparatively colourless. I have vainly endeavoured to prepare similar 

 compounds with the triphenylic derivative of rosaniline. . . 



