WHICH NITROGEN IS SUBSTITUTED EOR HYDROGEN. 
711 
ON THE PRODUCTS OF DECOMPOSITION OF THE DIAZONITROBENZOL COMPOUNDS. 
These substances, as far as my observations go, are decomposed under the influence 
of reagents like the other diazobenzol compounds; and their transformations may be 
expressed by corresponding equations. The nature of their products of decomposition 
may in fact be safely predicted beforehand, as the same isomerism which characterizes the 
compounds already described is observable. It appeared of sufficient interest to trace them 
somewhat more fully. I could not have given the comparative history of the products 
of decomposition, however, without deviating too far from the main direction of this 
investigation, and I must therefore reserve for a future opportunity a more intimate 
acquaintance with these interesting bodies. A few illustrations will show how promising 
a harvest of interesting results may be expected from such an investigation. One 
peculiar fact deserves mention here. I had taken it for granted that the same relations 
would be exhibited between the isomeric diazonitrobenzol compounds and the isomeric 
acids of the formula € 6 H 5 (NG 2 ) 0 (the nitrocarbolic acid of Hofmann and the isonitro- 
carbolic acid of Fritsche) as that observed between the compounds of diazobenzol and 
carbolic acid, and that their deportment would be represented by the formula 
€ 6 H 3 (NG 2 ) N 2 , NHG 3 +H 2 G=€ 6 H 5 (NG 2 )G+NHG 3 +N 2 . 
V ) V. . ) 
V m V 
a-f 3 Nitrate of diazonitro- a-/3 Nitrocarbolic 
benzol. acid. 
The assumption has not been verified. On boiling these diazonitrobenzol compounds 
with water, they are certainly decomposed, after some time, with evolution of nitrogen 
gas, but neither the a nor (3 compound furnishes under these circumstances either of 
the well-known phenylic substitutes. In both cases a brownish and easily fusible sub- 
stance is obtained, which readily dissolves in alcohol and ether, but which can in no 
manner be made to crystallize. I have not ascertained whether this substance deports 
itself differently according to its origin (from the a or / 3 compound), nor have I analyzed 
it, but I presume that, judging from the progress of its formation, and also from the 
weak acid properties it exhibits (dissolving in potassa and being reprecipitated by hydro- 
chloric acid), its composition is probably represented by the formula 
€ 6 H 5 (NG 2 )G. 
On heating an alcoholic solution of the perbromide of a diazonitrobenzol, it is readily 
decomposed according to the equation 
€ 6 H 3 (NG 2 ) N 2 , HBr 3 =G 6 H 4 (NG 2 )Br+N 2 +Br 2 . 
V -V ' ' V ’ 
a perbromide. Bromonitrobenzol. 
A portion of the bromonitrobenzol formed in this manner separates in crystals on 
cooling, provided the amount of alcohol employed has not been too large ; the rest is 
precipitated on the addition of water. The crystals are purified by pressure between 
filter paper and distillation, when they pass over as a slightly yellowish oil, which soon 
solidifies to a crystalline mass. The bromonitrobenzol thus prepared is.difficultly soluble 
