E,YAN AND Egan — The Acttoti of Nitrous Acid, Sfc, on Urethanes. 167 



its solutions in glacial acetic acid and carbon tetrachloride after these had 

 been treated with nitrous acid for lengthy periods. 



We found that nitrous fumes reacted with a cold ten per cent, solution of 

 the urethane in carbon tetrachloride solution, yielding 4-nitro-phenyl-benzyl 

 ether. When the reaction was allowed to proceed for a longer period, 

 4-10-dinitro-phenyl-benzyl ether was the main product. 



In contrast with the other bodies examined, nitrous acid reacted quickly 

 with diphcnylamine m both acetic and carbon tetrachloride solutions; 4-nitro- 

 diphenyl-nitrosamine \_cf. H. Kyan and V. Kyan, Proc. ll.I.A., vol. xx.xiv, Nos. 

 10 and 1 2J was obtained in quantity after six weeks from a five per cent, solution 

 of diphenylamine in glacial acetic acid to which butyl nitrite had been added, 

 and which had been allowed to remain at the room temperature for six weeks. 

 From a similar solution in carbon tetrachloride, this compound was also 

 obtained together with a mixture, the constituents of which were not 

 separated. 



EXI'EUIMENTAL. 



A. — Action of Nitrous Acid and Nitrous Fumes on Urethanes. 



I. Phenylurethane. 



(«) Nitrous Acid. — 1. Six molecular amounts of butyl nitrite wore added 

 to a solution of 5 grams of phenylurethane in 100 grams of glacial acetic 

 acid, and the solution was allowed to remain in a stoppered flask at the 

 temperature of the room for two months. The mixture acquired a slight 

 yellow colour, but otherwise its appearance did not change appreciably. It 

 was poured into twice its volume of water. The upper, oily layer was 

 separated, and from it, by evaporation at the room temperature, a crystalline 

 solid was got, which after recrystallisation from alcohol, proved to be 

 unchanged phenylurethaiw. A further quantity of phenylurethane was 

 extracted by ether from the lower, aqueous layer. 



2. In another and similar experiment in which alcohol was the solvent, 

 butyl nitrite and hydrochloric acid gave after two months a mixture from 

 which the only substance isolated was unchanged phenylurethane. 



3. Nitration took place, however, in a third experiment which was similar 

 to the other two, but in which carbon tetrachloride was the solvent. After 

 remaining at the room temperature for about two months some crystalline 

 matter with a little oil floated on the surface of the carbon tetrachloride. The 

 solid matter did not increase in quantity appreciably when the reaction was 

 allowed to proceed for another month. The colourless, tabular crystals melted 

 at 128-130'' C. On recrystallisation from diluted alcohol, colourless needles 

 were obtained melting at 131°-132° C. The melting point "was not changed 



