WHICH NITROGEN IS SUBSTITUTED EOR HYDROGEN. 
683 
PRODUCTS OF DECOMPOSITION OF THE DIAZOBENZOL COMPOUNDS. 
The transformations which the molecule of diazobenzol undergoes through the influ- 
ence of various reagents are numerous, and there is probably no other body to be met 
with in the large field of organic chemistry that surpasses it in this respect. The pro- 
ducts of decomposition to which it gives rise frequently possess new and very distinctive 
features ; more frequently, however, they belong to the benzol or phenyl group, in which 
latter case their formation depends upon the great inclination which the two nitrogen 
atoms of the diazobenzol exhibit to escape and to cede their place to other atomic groups 
of the same value (HH). 
Deportment of Diazobenzol Compounds when boiled in an aqueous solution. 
The transformation of nitrate of diazobenzol, under the influence of boiling water, 
has already been noticed. A similar change is observed with regard to its sulphate and 
hydrobromate, as will be seen from the following equations : — 
Sulphate Pbenylic 
of diazobenzol. acid. 
Hydrobromate Pbenybc 
of diazobenzol. acid. 
On the other hand, the compounds of diazobenzol with metallic hydrates exhibit a very 
different deportment with boiling water. By neutralizing the metal, however, with a 
mineral acid, the decomposition takes place in accordance with the above equations. 
Action of Alcohol upon Nitrate of Diazobenzol. 
By gradually and cautiously introducing the nitrate of diazobenzol into a moderate 
quantity of alcohol (previously warmed to about 50° C. in order to accelerate the solu- 
tion), and submitting the whole to distillation in a water-bath, a yellow residue remains, 
which solidifies to a crystalline mass on cooling, and dissolves readily in alkaline solu- 
tions, whence it was inferred that it had the character of an acid. There was, in fact, 
no difficulty in ascertaining that this body was nothing else than dinitrophenylic acid, 
possessing all the well-pronounced properties of this compound ; and to prove this most 
conclusively, it was converted into the characteristic amidonitrophenylic acid. Dinitro- 
phenylic acid, however, is not the only product to which this reaction gives rise ; for on 
mixing the distillate with water an oily body separates, which collects upon the fluid, 
especially when its specific gravity has been increased by the addition ®of a solution 
of chloride of sodium. This oil may be removed by means of a separating funnel and 
dried over chloride of calcium. It possesses, when rectified by distillation, all the pro- 
perties of ordinary benzol. I have converted it into dinitrobenzol by the action of 
fuming nitric acid, and have found this latter identical with that prepared from coal-tar 
mdccclxiv. 4 Y 
