222 Proceedings of the Royal Irish Academy. 



diphenylamine in a manner similar to that described for the broniination of 

 diphenylnitrosamine. 



Two grams of bromine dissolved in 125 c.c of chloroform were added 

 slowly to a solution of 3 grams of tetrabromo-diphenylamine in 15 c.c of 

 chloroform. The mixture was then placed in bright sunlight for about six 

 hours, hydrobromic acid being evolved, but not very copiously. After 

 remaining overnight the solvent was evaporated, and the residue was washed 

 with chloroform. The product consisted of white prismatic crystals, mixed 

 with a small amount of an oily substance which was difficult to remove. The 

 substance, which melted at 221-:: ('.. wa< evidently identical with the hexa- 



mo- diphenylamine obtained from diphenylnitrosamine. 



III. ./ / nine o,i b-Nitro-Diphmylnitrosamint. 



A solution e ! bromine in 25 c.c. of chloroform was added in 



ill quantil itiou of 1 gram of 4-nitro-diphenylnitiosamine in 



10 c.c. of chloroform. When about half the bromine had been added, the 



ition of nitrous fume- iced, and a thick yellow precipitate formed. 



The evolution of hj .... acid was not observed. The mixture was 



to remain in sunlight for a quarter of an hour, alter which, by 



evaporation of the chloroform and the excess of bromine, a yellow solid 



which was purified by llisation from chloroform. "When 



beat) _ _ ind melted at 2 It consists of fine bright 



yell rhich are soluble in chloroform, alcohol, and benzene. A 



d of bromine in the compound gave the following result : — 



gram of the Bubstance on treatment with sodium and alcohol gave 



an amount of sodium bromide which on precipitation with Bilver nitrate 



led (M52 _ :omide. 



sponding i" Bi 42*3 



H.T.i N'"_, nh requin - Bi 272 

 il I. ,NO.) NH requires Br 42-9 

 ii Nil requires Bi 53*1 



Tli*- i dibromo-4-nitro-diphenylamine, which so 



far as we are aware has not been previously obtained. 



In carrying out the analysis of this substance, as also in the analysis of the 

 compound obtained in the following experiment, the ordinary method of 

 estimating the bromi iing ex 10 AgNO, and titrating the 



excess ins of a thiocyanate, could not be employed owing to the deep 



colour of the solution The silver bromide precipitated from the acid 

 sol'. re, weighed. 



