Ryan and Glovkr — Nitro Derivatives of Diphenylamine. 103 



%4-10-Trinitiv-5-Meileyl-diphenylamine consists of glistening straw- 

 coloured, prismatic needles, which are only slightly soluble in most organic 

 solvents, excepting acetone. 



The crystals were turned red by contact with concentrated sulphuric acid, 

 in which they dissolved, forming a faintly yellow-coloured solution which 

 remained apparently unchanged on addition of a crystal of sodium nitrite. 



9. 2.6.9- l'rinitro-3-Methyl- Diphenylamine 



(0,N) s (CH,)C,H*NH . C.H 4 N0 2 . 



A substance which is probably 2.6.9-trinitro-3-methyl-diphenylamine was 

 obtained in small quantity by prolonged heating of an alcoholic solution 

 of |3-trinitro-toluene and m-nitraniline. It consists of glistening, straw- 

 coloured, prismatic needles, melting with slight decomposition at 199 3 C, 

 and sparingly soluble in most organic solvents. Its amount was insufficient 

 for analysis. 



1). I'etranitro-Diphenylamines. 



10. $4.8.10- Tdranitro-Diphenylamine (0 2 N) 2 C c H 3 . NH . C 6 H 3 (N0 2 ) 2 . 



The symmetrical tetranitro-diphenylamine was obtained in a poor yield' 

 by heating 3 g. of 2.4-dinitro-bromobenzene and 2 g. of 2.4-dinitro-aniline ' 

 in nitro-benzene solution with 2 g. of anhydrous potassium carbonate, traces of 

 copper dust, and potassium iodide for several hours to a temperature of about 

 160° C. The residue left after distilling the nitro-benzene in a current of steam 

 solidified on cooling. It was filtered, washed with alcohol, and re-crystallised 

 a few times from glacial acetic acid. Prepared in this way it consisted of 

 brownish prisms which melted at 199-200° C. A mixture of it with an equal 

 amount of the symmetrical tetranitro-diphenylamine obtained by the direct 

 nitration of diphenyl-nitrosamine also inelted at the same temperature. 



11. $4.6.9- Tetranilro-Diphenylamine (0 2 N) 3 C„ 1 1 .. . N II . CcH.NO,.. 



Picryl-m-nitraniline was obtained by Austen (he. cit.) by boiling an 

 alcoholic solution of picryl chloride with m-nitraniline. We obtained it by 

 a similar method, and found that it consisted of short yellow prisms melting 

 at 210° C. (corr.) — a temperature slightly higher than that (205°) given by 

 Austen. 



It is not identical with the tetranitro-diphenylamine (MP 190° C.) 

 obtained by the prolonged action of isoamyl nitrite and air (see below) 

 on 2.4.9.-trinitro-diphenylamine. 



1 Dinitro-anilinecan be conveniently prepared, in almost quantitative yield, by allowing 

 a solution of dinitro-bromo-benzene in alcoholic ammonia to remain in a stoppered flask 

 for a few days at the ordinary temperature. 



