314 N-Heterocycles
O 2 N NH 2NO 2
143NHPh NNNNO Ph
2
144O 2 N
NNNNO 2O 2 NNO 2O 2 N145 NO 2
(BTX)NaNO 2 , AcOH HNO 3 , H 2 SO 4Figure 7.55latter with mixed acid yields BTX (145). The reaction of (144) with weaker nitrating agents
has been used to synthesize derivatives where the phenyl ring is either mono- or di-nitrated.^92
BTX has been suggested for use in thermally stable detonators, although its high sensitivity to
impact is a distinct disadvantage.
NO 2NO 2O 2 NHH
NO 2 NO 2 NNO 2146NO 2O 2 N NNN
NO 2O 2 NO 2 N
O
147conc. H 2 SO 4
NFigure 7.56The benzotriazene-1-oxide (147) has been synthesized from the intramolecular acid-induced
cyclisation ofN,N′-dipicrylhydrazine (146).^93
7.5 5-Membered rings – 4N
The high nitrogen content and the endothermic nature of the tetrazole ring lends itself to the
synthesis of energetic materials. Compounds such as 1-Htetrazole and 5-aminotetrazole can
be used as nucleophiles to incorporate the tetrazole ring into other molecules. 5-Aminotetrazole
is synthesized from the reaction of dicyandiamide with sodium azide in hydrochloric
acid.
Cl
NO 2NO 2
67O 2 N HN
NO 2NO 2
149O 2 NNNHNN
NNNN
HH 2 N148EtOH, 80 °C
70 %(PAT)Figure 7.57