Chemistry. — “On some nitro-derivatives of dimethylaniline’’. 
By M. J. Sur. (Communicated by Prof. van Rompuren). 
(Communicated at the meeting of June 28 1919). 
In 1914 a paper was published by van Rompuren and Miss Wensink ') 
in which the action of ammonia and methylamine on 1, 2, 3, 4. 
trinitrodimethylaniline was described. The remarkable phenomenon 
was here described that, besides the nitro-group in the 3-position, 
also the dimethylamino-group was replaced by the amino- or 
the methylamino-group as the case might be. At the instigation of 
Prof. van Romsuren 1 have undertaken a more extensive investi- 
gation into the behaviour of amines and, in general, of compounds 
containing an amino-group, with respect to the trinitro-derivatives 
of dimetbylaniline, in particular the 1.3.4.6. isomeride. These investi- 
gations are, however, still in the initial stage, and will be deseribed 
in due course in a thesis. 
Before undertaking the research above indicated, it appeared to 
me desirable to study somewhat more accurately the reaction in 
which the two isomeric trinitro derivatives of dimethylaniline are 
produced. In the nitration of 1.3.4 dinitromethylaniline?) the prin- 
cipal product is always the 1.3.4.6. derivative; the isomeric 1.2.3.4. 
compound is only formed in small quantities. Since, however, it is 
precisely the latter, in consideration of the position of the nitro- 
groups, which reacts the most easily, it seemed to me to be worth 
while to try to establish the conditions in which a better yield of 
this substance could be obtained. 
In spite of numerous attempts in which the experimental conditions 
were varied between the widest limits, [ was not successful in so 
modifying the conditions that the yield of 1.2.3.4 trinitro-dimethylamine 
was increased to any appreciable extent. In these experiments the 
great influence which the presence of nitrous acid exerts on the 
reaction velocity, was again most distinctly apparent; a phenomenon 
which has already been repeatedly observed in nitration experiments, 
') These Proceedings, XVII, 1034 (1915). 
2) Van Rougvrou, Verslagen Kon. Akad. v. Wet. 23 Webr. 189h, III, 257. 
