~ 210 
198—199°. By treating this nitrate, in the manner described, with 
absolute nitric acid in the cold it is recovered unchanged but if the 
solution is heated to boiling the nitroderivative NO,N(CH,CO,CH,), 
is formed which is not, or but little, soluble in cold water so that 
it may be precipitated by pouring the nitric acid solution into coid 
water. From acetic ether, in which it is soluble, it is obtained in 
silky delicate scales which melt at 63°.5. 
Iminodiacetamide HN(CH,—CONH,), gave with one mol. of NO,H 
a nitrate which was obtained from the aqueous solution, by addition 
of absolute alcohol, in beautiful lustrous leaflets which melt at 206° 
with decomposition. If this nitrate is placed in absolute nitric acid, 
an evolution of gas takes place after a short time, as in the case 
of all amides of N,O; when this has ceased, or has been accelerated 
by warming, the nitro-iminodiacetic acid is obtained. 
Iminodiacetimide HN(CH,CO),NH, which was made according to 
the directions of Jonekrrs, also gave compounds with acids. We 
prepared: (1) the HCl compound in lustrous, beautiful crystals which 
are decomposed on heating above 180°; (2) the NO,H compound, also 
white crystals with a strong lustre, which when heated above 180°, 
are decomposed and turn a bluish-green. Both compounds contain 
one mol. of acid. 
When iminodiacetimide or its nitrate is dissolved in absolute nitric 
acid and the solution evaporated in vacuo over lime a crystal-cake 
is obtained which may be recrystallised from boiling dry chloroform 
in which it is very little soluble. It then forms beautiful colourless 
needles which have the empirical composition of a mononitroderivative. 
This nitroiminodiacetimide NO,N(CH,CO)NH spontaneously turns a 
dark blue, especially in not quite dry air and its aqueous solution 
on warming first turns green, then blue and deposits an almost 
black amorphous substance soluble only in strong sulphuric acid 
with an indigo-blue colour. 
In order to render it more probable still that the nitro-group 
is attached to the nitrogen situated between the CH,-groups, the 
acetyliminodiacetimide CH,CON(CH,CO),NH was prepared first of all 
by subliming in vacuo acetyliminodiacetamide, which according to 
JoNGkEES decomposes at 203°. On recrystallising the sublimate from 
methvlaleoho] splendid small crystals were obtained which melt at- 
167—168° and according to analysis, have the empirical composition 
of acetyliminodiacetimide. They are insoluble in benzene, petroleum 
ether and acetic ether. The same substance was prepared by boiling 
iminodiacetimide with acetic anhydride. This acetyl derivative was 
dissolved in absolute nitric acid and the solution evaporated in vacuo 
