( 298 ) 
(D. 1.48) we obtain 1.2.4 dinitrodiaethylaniline (m.p. 80°) as I have 
demonstrated previously *). 
If, however, diethylaniline (1 mol.) is dissolved in twenty times 
its weight of sulphuric acid (D. 1.84) and if to this solution are 
cautiously added 2 mols. of nitric acid dissolved in about five 
times the weight of sulphuric acid, care being taken that the tempe¬ 
rature of the nitrating mixture does not rise above 5°, and if, after 
a few hours it is poured into iced water, a more or less deep yellow, 
crystalline product is obtained. 
If this is collected and the filtrate neutralised to a large extent 
with sodium carbonate, a fine dark red compound is separated. 
It may be stated here that this experiment has been carried out 
many times; strange to say the results were often quite different 
although the conditions of working were practically the same; as 
will now appear, it depends on the quantity of iced water into 
which the mixture is poured. 
Recrystallisation of the yellow crystalline mass from alcohol gave 
as main product a compound melting at 59°, a small quantity of a 
fine orange red product m.p. 95°, being also occasionally deposited. 
If the latter was recrystallised I often obtained yellow as well as 
orange red crystals which, however, melted at the same temperature 
(95 ). Sometimes, on recrystallising the compound melting at 59°, 
the orange crystals melting at 95° were obtained, so that it looked 
as if the compound with the lower melting point passed into that 
with the higher one. 
The dark red substance separated by means of the alkali, when 
recrystallised from alcohol, melted at 76°. 
The elementary analysis gave the same result for all these sub¬ 
stances ; the figures obtained showed that they all had the composi¬ 
tion of dinitrodiethylaniline. 
The peculiar behaviour of the above products melting at 59° and 
95 rendered a closer investigation desirable and finally I succeeded 
m finding the key to the problem; the substance melting at 59° is 
a compound of two different dinitroderivatives of diethylaniline, and 
t e one melting at 95° occurs in two, and probably more, modifications. 
If we dissolve one part of the substance melting at 59° in 11.4 
parts of hydrochloric acid (D. 1.14) and then cautiously add water 
whilst shaking, a yellow product separates, which, however, soon 
turns oiange, as a rule. After 6 parts of water have been added 
the crystals are collected and washed with a little hydrochloric acid 
l ) Rec. T. II p. 36 [1888]. 
