318 Scientific Proceedings, Royal Dublin Society ^ 



in each case 2 g. of diphenylether in 40 g. ol' acetic acid, 1, 2, 3, 4, and 5 

 molecular amounts of nitric acid (Sp. g. 1-52) were added. A light-yellow 

 coloration was developed, which deepened, in the case of the solutions containing 

 4 and 5 molecular amounts of the acid, to a light red. When the contents 

 of each bottle were poured into water a colourless oil separated. The oil 

 rapidly changed into a crystalline solid, which melted at 28° C, and proved 

 to be unchanged diphenylether. About 90 per cent, of the ether was recovered 

 in each case. 



(e) In Acetic Acid Solution at ordinary concentrations. — Using two similar 

 solutions of the ether in acetic acid containing, however, 12 and 24 molecular 

 amounts of nitric acid respectively, deep-red solutions were obtained with 

 a considerable evolution of heat. On pouring either of the solutions into 

 water a light-red oil was precipitated. The oil was extracted with ether, and the 

 ether layer was freed from 2-4-dinitrophenol by washing it with dilute alkali. 

 The ether on evaporation left a solid which separated from alcohol in the 

 form of prisms, melting at 56° C!., and probably consisting of slightly impure 

 4-nitrodiphenylether. 



(/) In Carbon Tetrachloride Solution. — To each of three solutions containing 

 2 g. of diphenylether in 40 c.c. of carbon tetrachloride were added 1, 3, and 5 

 molecular amounts of nitric acid (Sp. g. 1-52) respectively. These solutions 

 were allowed to remain at the temperature of the room for 6 weeks. The 

 bottle to which 1 molecular amount of acid had been added was at first yellow 

 in colour, and contained a few transparent prisms mixed with a deep-red 

 oil floating on top of the carbon tetrachloride. As the reaction progressed the 

 oil was gradually converted into a brown-tariy substance. The carbon 

 tetrachloride was distilled, and the oil which remained was. extracted with 

 ether. The ether layer was freed from 2-4-dinitrophenol by washing it with 

 dilute alkali. The ether on evaporation left an oil which on distillation with 

 steam was found to contain unchanged diiahenylether. The residual oil gave 

 a few crystals which were washed with alcohol, and were then found to be 

 4-nitrodiphenylether. 



The remaining sohitions were examined in a different manner. The carbon 

 tetrachloride was orange-yellow in colour and had a dark-red oily layer above 

 it, containing large thick prisms. An equal volume of water was added to 

 the mixture, and the carbon tetrachloride was separated from the aqueous 

 layer, Avhich was extracted with ether. When the ether solution was freed 

 from 2-4-dinitrophenol, by washing it with dilute potash, it left on evaporation 

 a somewhat oily solid. On crystallising this solid from benzene it separated in 

 the form of blunt prisms, which melted at 143° C, and consisted of 4-10- 

 dinitrodiphenylether. When the carbon tetracliloride layer was washed with 

 dilute alkali and allowed to remain for some time a solid separated, and this 

 was filtered. The filtrate on complete evaporation left an oil containing some 

 unchanged diphenylether. The solid which had separated from the carbon 

 tetrachloride was warmed with alcohol. A portion which had not dissolved 

 proved to be 4-10-dinitrodiphenylether. By evaporating the alcoholic solution 

 a solid was obtained. This was dissolved in warm petroleum ether from which 

 it separated as colourless crystals, melting about 95° C, and obviously 

 consisting of 2-10-dinitrodiphenylether, which melts, when pure, at 103-5° C. 

 Similar results were obtained from the solutions to which 3 and 5 molecular 

 amounts of nitric acid had been added, different amounts of the nitro compounds 

 being, however, obtained from the different solutions. 



