224 



Qi \-chloro-2,^d,'i-trinltrohenzene. Iii Ihe nitmtion of 



/\ l-cIiloro-2,3-dinitrobeiizejie by tlie method given 



III. I I " under II, tlie oil from which II was crystallized 

 \//N0, contains this third isomei'. When the oil stands for 



^^"i a long time, the isomer crystallizes out of it in 



colourless needles of the melting-point of 69°. They are purified by 

 recrystallization from alcohol. The structure of this compound can 

 also be determined by treatment with alcoholic ammonia. If the 

 action of the ammonia is allowed to last only for a short time, 

 only one of the nitro-groups is replaced by NH,. q| 



The aniline formed is 3-chloro-2, 6-dinitraniline for /A ^^^^ 



/ \ N() 



l-chloro-2, 4-dinitrobenzene is obtained from it II' 



by deamidation. This aniline has the melting-point \/^H, 



112°; it was unknown up to now. ^^ 



n\ i-chloro-^,4:,Q-i>'i7iitrobenzeiie. This compound was 



^0 y\ already prepared by Nietzki by nitration of J -chloro- 



IV. I I 3,4-dinitrobenzene. On repetition of his experiments 

 \/^NOj it appeared to me that tlie yield was small, and 



» especially very uncertain, because either the nitration 



remains incomplete, or the reaction is so violent that total destruction 

 ensues. It is therefore, better to proceed as follows : 



CI NH, NO, 



N0,/\ N0,//\ N0,/\ 



\/Cl \/Cl \/Cl 



NO, NO, NO, 



The substitution of NH, for Gl takes place in alcoholic solution 

 on the waterbath with addition of gaseous ammonia, till a test- 

 sample shows the correct melting-point of 174°. According to Körner 

 and CoNTARDi NO, Gan then be substituted for NH,. The crude 

 product is coloured black. It can be purified by boiling with nitric 

 acid 1.4, followed by recrystallisation from alcohol. The melting- 

 point is 116°, as has been given by Nietzki. 



No method of preparation CI has as yet been found for the 



last isomer, the l-chloro-2, 3,^0, /\N0, 6-trinitro-benzene ; probably 

 it is also present in the oil I .L^.^ obtained in the nitration of 

 l-chloro-2,3-dinitrobenzene. ^^ * 



Amsterdam, June 1922. Org. Cliem. Lab. of the University. 



