220 Proceedings of the Royal Irish Acafi< y >/t>.. 



into tetrabromo-, and even into hexabronio-diphenylaruine. the mononitro- 

 aud diiiitro-diphenylauiiues, examined by ns, formed, only dibromo deriva- 

 tives ; and the tetranitro-diphenylamine did uot brominate at all. under 

 the same conditions. 



In connexion with a volumetric process such as that of Berger, or a 

 gravimetric process like that of Dieger Ztschr. f. d. yes. Sehiess. u. Sprengs- 

 toftwesen, iv. 1909. ]•. 123), for the estimation >>i diphenylauline in a 

 powder, which depends on the action of bromine on diphenylamine, we may 

 point >'iit that dipheuylnitrosaiuine and 4-nitro-diphenylnitrosamine are 



itile with steam: and that any of these which may have escaped 

 interaction with the alkali will volatilise during the experiment, and will be 



-••iit with diphenylamine in the distillate. The higher nitro derivatives 



are not appreciably volatile with steam. Also the temperature at which 



the bromination occurs, and the time allowed for the completion of the 



change, will affect the estimation. A rise o| temperature, due, for instance, 



the bromine, or contact of the bromine solution with the 



-. produces a mixture of tetrabromo- and hexa- 



iiylamines. In cases Bueh as these the estimation of the 



diphenylamine on the assumption that the only product formed is tetra- 



lylamine must necessarily give inaccurate resn '• - 



Experimental. 



I. .: on D 



- of diphenylnitrosamine.ro 5.c.& of chloroform*, 



lution • grains of bromine ii reform was added in 



a ;\ time. At first nitrous fumes robed ^ and 



when a oniine solution had been added, a copious 



- noticed. Towards the end of the reaction 



ibromic acid olve<L The mixture was allowed to 



ad in the morning it was placed in the sunlight for an 



hour. The run and I mine were then removed by 



and the residue, which consisted of a brownish 



from chloroform. The chloro-' 



- lution "i. _ . a white solid which, when purified by further 



: in, formed white, monocliiiic plates (or Hat 



prisms) mell _ 11 The parent liquids from this substance yiei 



a yellow solid whi illised in Hue needles melting at 17" 



the bromination in the following manner a much larger 



tained : — 1 ^jam 

 Ived in ldc.e. of chloroform, was added rapidly. 



