100 Proceedings of the Royal Irish Academy. 



constant stirring. The colourless precipitate was filtered, washed free from 

 salt by water, and then washed with a little alcohol and ether. The pure 

 substance, the yield of which was about 80 per cent., consisted of colourless 

 needles melting at S9-90 3 C, and gave on analysis the following results : — 



01 368 g. substance gave 204 cc. moist nitrogen at 22° C. and 

 704 m.m.p. 



corresponding to X 170 

 CH.OjXj requires N 17-3. 



S-Xfitro-dtphenylwUrosamine consists of colourless, acicular crystals, which 

 are readily soluble in acetone or chloroform, and sparingly in alcohol or 

 acetic acid. Its solution in concentrated sulphuric acid had a violet colour. 



B. Dinitro-Diphenylamines. 

 3. J. 'rl'in Uro-dipkmylam ine (0,N),C,H,NH . C 11 



Following the method of Clemm(Ber. d.Dtsch.Chem.Ges. hi (1870), p. 128) 

 we obtained 2.4-dinitro-diphenylamine by the action of aniline en 2.4-dinitro- 

 chlorobenzene. The prod in t after being washed with dilute hydrochloric acid, 

 .!H>>"1 from alcohol and chloroform. It consisted of long orange- 

 red needles, melting at 156 157 «'.. which were soluble in acetone or glacial 

 acetic acid, slightly in ether or carbmi tetrachloride, sparingly in alcohol, and 

 readily in chloroform or benzene. 



With alcoholic potash it formed an orange-red solution which became 

 blood-red on being wanned, and with concentrated sulphuric acid it gave a 

 nearly colourless solution which lutame brown on addition of a trace of 

 sodium nitril 



[-Dintiro-diphenyfa To a solution of 1 g. of 2.4-dinitro- 



diphenylamine in 60 cc. of glacial acid, 2 cc. of isoamyl nitrite were added, 

 and the mixture was allowed to remain in a cold room for a few days. 

 The solution, which was at first orange in colour, gradually became much 

 lighter in colour, with simultaneous separation of a pale yellow solid. 



After addition of water the solid was filtered and washed, first with water, 

 afterwards with alcoboL When re-crystallised from chloroform it melted at 

 149-151" C, and gave on analysis the following results : — 



01 029 g. substance gave 162 cc. moist nitrogen at 14 c C. 

 and 759 m.m.p. 



corresponding t" X 192 

 I 11 X, 1 ' requires N 194. 



