330 



Proceedings of the Royal Irish Academy. 



boiled, the indamiue is converted into an eurhodine, Neutral Eed, mixed 

 with the leuco componnd of the indaniine : — 



ci 



"(^"3). 



NH 



CH 



-NH, 



(CHjlN 



Neuteal Red. 



Leuco Tolylene Blue. 



In a similar manner the indamine Phenylene Blue and the eurhodine 

 Neutral Violet were obtained from the hydrochloride of nitrosodimethyl- 

 aniline and 5;i-phenylenediamine. 



By causing nitrosophenylurethane and the hydrochloride of wi-toluylene- 

 diamine to interact under conditions such as those which obtain in the 

 preparation of the above dyestuffs, we hoped to prepare an indamine or an 

 eurhodine of the formula 



CH OOCNH- 

 2 5 



CH, 



'VX/'^NH 



or 





CgHjOOC- NH 



respectively. 



When solutions of the two substances in warm methylated spirit were 

 inixed and carefully concentrated, a small amount of bluish-black prismatic 

 crystals' with a purple lustre separated on cooling. It was not, however^ 

 found possible to obtain a satisfactory yield of the substance, slight variations 

 in the method invariably giving a negative result. This crystalline substance 

 proved to be the hydrochloride of an amorphous, reddish-brown, fluorescent 

 base. 



In addition to the hydrochloride of the base, a straw-coloured, crystalline, 

 neutral substance was sometimes got by the action of «i-toluylenediamine 

 hydrochloride on the nitrosourethane. Although this substance has a per- 

 centage of nitrogen approximating to that of an indamine from the 

 nitrosourethane and toluylenediamine, it cannot be regarded as a derivative 

 of the amine, since the same substance was formed by the action of a-naph- 

 thylamine on the nitrosourethane. The body was, therefore, simply a 

 derivative of the latter substance. 



The analysis of the hydrochloride of the base showed clearly that the 

 substance was neither an indamine nor an eurhodine from nitrosophenylure- 

 thane and m-toluylenediamine. As the formation of the straw-coloured 

 by-product indicated that the nitrosourethane could also undergo a change, 



