112 
DR. A. W. HOFMANN’S RESEARCHES REGARDING THE 
of chlorine or bromine into the compound. Bromaniline still retains a strongly 
alkaloidal character which in dibromaniline is so far impaired that by simple ebulli- 
tion it is separated from its aqueous saline solutions ; tribromaniline, lastly, is a per- 
fectly indifferent compound. Now if we recollect that in monobrominated and dibro- 
minated phenole (obtained by M. Cahours, by distilling respectively, bromosalicylic 
and dibrornosalicylic acid), the original character of hydrated oxide of phenyl is 
gradually altered and becomes in tribromophenole (brornophenisic acid of M. Lau- 
rent) powerfully acid, we cannot be surprised to find that the gradual development 
of electronegative properties in the radical should affect the nature of a basic system 
in which it replaces hydrogen. We have two parallel groups of bodies, the chemical 
character of which is differently affected by the modification induced in the radical, 
existing in both, by the assimilation of bromine. 
Hydrated protoxide) , 
of phenyl J 
Tribromophenole ) 
Brornophenisic acidj 
f ^ 
2 H3 
0, slightly acid. 
Phenylamine 
'“LBrJ 
H 
0, more so. 
Bromophenylamine ... 
fH,l 
“[Br.J 
H 
■ 0, more so. 
Dibromophenylamine < 
H 
\BtJ 
H 
I 
[BrJ 
0, powerfully acid. 
Tribromophenylamine < 
N, powerfully 
basic. 
N, less so. 
N, less so. 
N, neutral. 
Tribromophenylamine (tribromaniline) is a compound differing in its nature in no 
way from oxamide. Both these substances are ammonia, whose basic character has 
been counterbalanced by the insertion of a powerfully electronegative radical in 
the place of one of the hydrogen-equivalents. These two substances, when subjected 
to the influence of strong acids, comport themselves in exactly the same manner; 
they both reproduce ammonia, the one with formation of tribromophenisic, the other 
of oxalic acid. 
The paragraphs nov/ following are devoted to a brief account of the bases derived 
from aniline by the insertion of methyl and amyl. I have not however followed out 
the examination of these substances to the same extent, the principle having been in 
fact sufficiently established by the formation of the ethyl bodies. 
