294 Scientific Proceedings^ Royal Dublin Society. 



5. Action of Nitric Acid on 2-Nitrophenyl'benzylether. 



2-Nitrophenylbenzylether was prepai-ed synthetically by heating equivalent 

 quantities of 0-nitrophenol, benzyl chloride, and sodium ethylate on a water- 

 bath for 5 or 6 hours. The purified substance melted at 29° C. 



42 g. of this 2-nitrophenylbenzylether was gradually added to 168 c.c. of 

 nitric acid (Sp. g. 1-5) in a small round flask, which was kept cool by immersion 

 in a freezing mixture. 



The clear red solution so obtained was allowed to stand overnight, during 

 which time much crystalline matter separated. The contents were then poured 

 into a mixture of ice and water, and the yellowish-white precipitate isolated 

 by filtration, washed free from acid and dried. The yellow solid thus obtained 

 was boiled with benzene, and filtered while hot. The filtrate on cooling gave 

 white crystals, which, after repeated recrystallisations from chloroform, melted 

 at 187-188° C, and proved to be identical with 2-4-2'-trinitrophenylbenzylether 

 [mentioned in par. 4 (d)]. 



The white matter insoluble in boiling benzene after recrystallisation from 

 glacial acetic acid melted at 207-208° C, and was identical with 2-4-4'-trinitro- 

 phenylbenzylether. 



6. Action of Nitric Acid on 4-4-Dinitrophenylbenzylether. 



In the Absence of Solvents. — 1 g. of 4-4'-dinitrophenylbenzylether was 

 gradually added to 3 g. of nitric acid (Sp. g. 1-5) at 30-40° C. in a small 

 round flask and allowed to stand overnight, during which time some colourless 

 crystals separated. 50 c.c. of water was then added to the contents of the 

 flask, and the yellowish-white precipitate, which was isolated by filtration, 

 was washed free from acid and dried. 



On recrystallisation from glacial acetic acid, colourless, platy prisms were 

 obtained, which melted at 207-208° C, whilst a mixture of it with 2-4-4'-trinitro- 

 phenylbenzylether melted at the same temperature. Thus nitric acid acts on 

 4-4'-dinitrophenylbenzylether giving 2-4-4'-trinitrophenylbenzylether. 



2-4-4'-trinitrophenylbenzylether is insoluble in water, ether, chloroform, 

 alcohol, or benzene, either hot or cold. It is scarcely soluble in cold xylene 

 or glacial acetic acid, but dissolves fairly easily on boiling. 



7. Action of Nitric Acid on 2-4-4'-Trinitrophenylb6nzyl6ther. 



(a) In the Absence of Solvents. — 1-0 g. of 2'4-4'-trinitrophenylbenzylether 

 was added slowly with shaking to 4 c.c. of fuming nitric acid (Sp. g. 1'52) in 

 a small round flask. No heat was evolved, and no apparent change was 

 observed. The yellow mixture was allowed to stand overnight and then poured 

 into water. A yellowish-whita precipitate was formed, which, after isolation, was 

 washed, dried, and recrystallised from glacial acetic acid. Colourless prisms 

 of unchanged 2-4-4'-trinitrophenylbenzylether were obtained. 



Under these conditions nitric acid is without action on 2-44'-trinitrophenyl- 

 benzylether. 



(5) The above experiment was repeated, but the mixture was this time heated 

 on a water-bath for 6 or 7 hours and allowed to stand overnight. The mixture 

 was then poured into water and the precipitate examined as before. 2-4-4'- 

 trinitrophenylbenzylether was again recovered unchanged. 



(c) The experiment was next attempted in the presence of 4 c.c. of fuming 

 sulphuric acid (20 per cent. SO3) — 1 g. of the 2-4-4'-trinitrophenylbenzylether 



