162 Synthetic Routes to AromaticC-Nitro Compounds
which is synthesized from the reaction of 2,4-dinitrochlorobenzene (95) with aqueous sodium
hydroxide.^225
Cl
NO 2NO 2
95OH
NO 2NO 2
98N
NO 2MeHNO 2
100OH
NO 2NO 2
4O 2 NN
O 2 N NO 2NO 2
101O 2 NMeHNO 3OCH 3
NO 2NO 2
99OCH 3
NO 2NO 2
7O 2 NH 2 SO 4 , HNO 3H 2 SO 4 , HNO 3EtOH, refluxNaOH, H 2 Oreflux
91 %MeNH 2 ,93 %MeOH, NaOHreflux
95 %or
H 2 SO 4 , HNO 3
or
Ac 2 O, HNO 3Figure 4.37Other explosives, such as 2,4,6-trinitroanisole (7),33b,^226 2,4,6-trinitroaniline (picramide),^227
and tetryl (101),^40 ,^228 are conveniently prepared from the nitration of the corresponding
2,4-dinitro derivatives, which in turn, are prepared from the reaction of 2,4-dinitrochloro-
benzene with the appropriate nucleophile.
NO 2O 2 NH
NNH
NO 2O 2 NNO 2O 2 NNNO 2 NNO 2NO 2 O 2 NCl
NO 2NO 2
95NH 2 NH 2CaCO 3 , H 2 O
+90
(HNAB)1022H 2 SO 4 ,
HNO 3refluxFigure 4.382,2′,4,4′,6,6′-Hexanitroazobenzene (HNAB) (90) can be synthesized from the nitration–
oxidation of 2,2′,4,4′-tetranitrohydrazobenzene (102) with mixed acid, the latter synthesized
from the reaction of aqueous hydrazine with 2,4-dinitrochlorobenzene (95) in the presence of
an inorganic carbonate.^214