[ 113 ] 



No. 14. 



THE ACTIOlSr OF THE OXIDES AND THE OXYACIDS OF NITEOGEN 



OK DIPHENYLURETHANE. 



By HUGH EYAN, D.Sc, 



AND 



ANNE DONNELLAN, M.Sc, 

 University College, Dublin. 



[Kead December 19, 1922. Printed February 22, 1923.] 



Inteoduction. 



It has been shown by one of ns, in conjunction with Miss P. Ryan (Pioc. E.I.A., 

 xxxiv, B, pp. 194 and 212), that d'iphenylnitrosamine can be converted by 

 nitric acid into nitro derivatives of diphenylamine and of diphenylnitrosamine more 

 easily and more smoothly than diphenylamine. Thus diphenylnitrosamine reacted 

 with nitric acid at the ordinary temperature and at low concentrations of the acids 

 with formation of mononitro- and dinitro-diphenylamines with their nitro- 

 samines, a trinitro- and a tetranitro-diphenylame. Under the same conditions 

 diphenylamine reacted less smoothly with nitric acid with formation of similar 

 nitro derivatives, together with relatively large amounts of brown resinous products, 

 obviously arising from a secondary oxidation process. The difference in the 

 behaviour of the two substances is probably due to the protective influence of the 

 nitroso group during the nitration, and in this connexion the results which we 

 obtained during the nitration of diphenylurethane may be of interest. 



By the action of concentrated nitric acid on diphenylurethane Hager(Ber. Dtsch. 

 Chem. Ges., xviii (1885), p. 2574) obtained 4-10-dinitro-dipbenylurethane and a 

 syrupy substance, which proved to be 210-dinitro-diphenyluretliane. So far as we 

 are aware, no other nitro derivatives of the substance have been obtained, nor has 

 its behaviour towards nitric acid at low concentrations of the interacting substances 

 been hitherto investigated. 



In our experiments we found that cold concentrated nitric acid converted 

 diphenylurethane into 4-nitro-diphenylurethane ; and we established the constitu- 

 tion of the latter substance by converting it, by means of alcoholic potash, into 

 4-nitro-diphenylamine melting at 133°-134° 0. 



With fuming nitric acid, on the other hand, we obtained the 410- and 

 2-10-dinitro derivatives, already described by Hager (loc.cit.). 



Tetranitro-diphenylurethane, hitherto unknown, was formed by the action ol a 

 mixture of sulphuric and nitric acids on diphenylurethane, and also on 4-nitro- 

 diphenylurethane. Since the tetranitro compound was converted by concentrated 

 hydrochloric acid into 2-4-8-10-tetranitro-diphenylurethane, it must be regarded 

 as 2-4-8-10-tetranitro-diphenylurethane. By the further nitration of the tetra- 

 nitro-urethane symmetrical hexanitro-diphenylamine was formed. 



SCIENT. PKOC. R.D.S., VOL. XVII, NO. 1\. ^ 



