Ryan & Drumm — Action of Oxides of Nitrogen on Dipheny tether. 317 



less plates, which melted at 56° C. As a mixture oJ; it with 4-nitrodipheiiyl- 

 ether (melting at 61° C.) melted about 58° C, and as the two bodies 

 crystallised in truncated rhombohedral plates, having an obtuse angle of" 112° 

 and an acute angle of 68°, the substance melting at 56° C. was probably 

 slightly impure 4-nitrodiphenylether. This compound, which was the chief 

 product of the reaction, was very soluble in ether or benzene, and moderately 

 soluble in cold alcohol. 



4. Action of Nitric Acid on DipJienylether. 



(a) In the Absence of Solvents. — 3 g. of diphenylether was added slowly to 

 15 g. of nitric acid (Sp. g. 1-4), contained in a flask, and the contents were 

 shaken. As the ether remained undissolved in the cold, the contents of the 

 flask were heated on a water-bath for an hour, when a copious evolution 

 of oxides of nitrogen took place. After heating for 5 hours a deep-red solution 

 with a small amount of a dark-red oil floating on top of the acid layer was 

 obtained. When the mixture was poured into a large excess of water a 

 dark-red oil was precipitated. This was extracted with ether, and the ether 

 layer was washed with alkali. The ether on evaporation gave a yellow oil, 

 which was warmed with petroleum ether in which a portion of it dissolved. 

 The petroleum ether on evaporation left a somewhat oily solid. This was 

 dissolved in alcohol, which on concentration gave colourless plates, melting 

 about 56° C, and probably consisting of slightly impure 4-nitrodiphenylether. 



The oil which remained undissolved by the petroleum ether was light-yellow 

 in colour, and was treated with various organic solvents from which, however, 

 it did not crystallise. On further nitrating this oil with nitric acid (Sp. g. 1-52) 

 a yellow crystalline solid was obtained which gave the following results on 

 analysis : — 



01000 g. substance gave 13-7 c.c. of moist nitrogen at 14° C. and 756 m.m. 



corresponding to N 16-02 

 CiaHeOgN, requires N 16-0. 



As it agreed in melting-point (195° C.) with the 2-4-810-t6tranitro compound 

 obtained from 2-4-dinitrochlorobenzene and 2-4-dinitrophenol, it must have been 

 2 4- 8- 10-tetranitrodiphenylether. 



(b) Action of Fmning Nitric Acid. — Nitric Acid (Sp. g. 1-52) was cooled 

 in a freezing mixture and diphenylether (1 g. of the ether to 5 g. of the acid) 

 was slowly added. A small amount of charring occurred, and there was a 

 copious evolution of oxides of nitrogen. The ether quickly dissolved in the 

 acid giving a red solution which, after remaining overnight at the temjierature 

 of the room, was poured into water. The white solid which was precipitated was 

 washed with alkali. After recrystallisation from acetone a solid separated, 

 which, when again crystallised from acetic acid, melted at 195° C, and was 

 identical with the tetranitro compound obtained in the last experiment. The 

 acetone filtrate on concentration gave a solid, which, after recrystallisation 

 from benzene, melted at 143° C, and consisted therefore of 410-d)nitrodiphenyl- 

 ether. 



(c) Action of Mixed Acids. — The sole product of the action at the ordinary 

 temperature of a mixtux*e of 5 parts of nitric acid (Sp. g. 152) and 5 parts of 

 concentrated " sulphuric acid on diphenylether was 2-4-8-10-tetranitrodiphenyl- 

 ether, melting at 195° C. 



(fZ) In Acetic Acid Solutiori at loiv concentrations. — To 5 solutions, containing 



