OF ARTS AND SCIENCES. 251 



obtained a liquid dibromtoluol, which on oxidation with nitric acid 

 yielded the dibrombenzoic acid melting at 151°-153° previously made 

 by Von Richter* from paradibrombenzol. 



The only point therefore not settled in regard to the constitution 

 of Grete's metabromdinitrotoluol was the position of the second nitro 

 group, which might be either para or ortho to the methyl. To deter- 

 mine this the metabromdinitrotoluol was heated with alcoholic ammo- 

 nia! Iq sealed tubes to 100° for 12 hours, when it was found to be 

 converted into a yellow substance, which had partly separated in the 

 solid state, and partly remained in solution in the alcohol, from which 

 it was obtained by evaporation. The product was purified by wash- 

 ing with water to remove the ammonic bromide, and crystallization 

 from hot glacial acetic acid, until it showed a constant melting point 

 (193°-194°), when it was dried at 135°, and the following analysis 

 showed that a dinitrometatoluidine had been formed. 



0.2658 gr. of the substance gave 51.2 c.c. of nitrogen at a temper- 

 ature of 24° and a pressure of 767.5 mm. 



Nitrogen 



The melting point showed that this substance is identical with the 

 dinitrotoluidine made by Hepp t by the action of alcoholic ammonia on 

 his y trinitrotoluol, but the constitution of this trinitrotoluol had not 

 been determined. Staedel § has also announced recently that one of 

 his students, Herr Adalbert Kolb, has prepared a dinitrotoluidine from 

 diuitrokresolether and determined its constitution as CHg, NH2, NO2, 

 NO2, 1, 3, 4, 6 ; but, as he neglected to give the melting point, we were 

 unable to tell whether it was identical with ours or not, and have 

 been forced to work out the constitution of our dinitrotoluidine by the 

 replacement of the araido group by hydrogen. In doing this some 

 difficulty was encountered because of the very slight solubility of the 

 dinitrotoluidine in alcohol, but we found on experiment that the Griess 

 reaction would take place satisfactorily in a mixture of acetone and 

 alcohol, and accordingly proceeded as follows. 2 grs. of the dinitro- 



* Ber. d. ch. G., vii. 1146. 



t When metabromdinitrotoluol was allowed to stand with alcoholic ammonia 

 in the cold, a dark blue solution was fornied at first, but the color gradually 

 changed to reddish brown. 



J Ann. Chem., ccxv. 371. 



§ Ber. d. ch. G., x.xii. 215. 



