5-Membered rings – 3N 311Laval and Vignane^73 reported the synthesis of the nitrotriazole (124) from the reaction of 3-
nitro-1,2,4-triazole with 3,5-diamino-1-chloro-2,4,6-trinitrobenzene. The nitrotriazole (124) is
a useful secondary high explosive, exhibiting high performance and a low sensitivity to impact.
N
N
HNH 2 N
NN
HNN
N
N
N
HN
NNNN
N
N
NNO 2 NNO 2KMnO 4
2(^125126)
(N-DNAT)
Ac 2 O, HNO 3
98
Figure 7.47
Chemists at Los Alamos National Laboratory (LANL) have shown interest in the 1,2,4-
triazole ring as a component of new energetic materials. During their study 1,1’-dinitro-
3,3’-azo-1,2,4-triazole (N-DNAT) (126), a potential additive for high-energy propellant for-
mulations, was synthesized from the oxidative coupling of 3-amino-1,2,4-triazole (98), fol-
lowed byN-nitration of the resulting product (125) with nitric acid in acetic anhydride.^74
N-Nitrotriazoles are less thermally stable than theirC-nitro isomers and so the isomeric
C-DNAT (127) is an important target. The thermal rearrangement of N-DNAT (126) to
C-DNAT (127) was not successful under the conditions employed.^75 C-DNAT (127) was
later synthesized from the oxidative coupling of the potassium salt of ANTA with potassium
permanganate. C-DNAT (127) burns without smoke or residue and has high potential for use
in advanced propellant formulations.^68
N
N
H
N
N
N
N
N
H
N
O 2 N NO 2
NN
N
O 2 N N NO 2
O 2 N NO 2
O 2 NNO 2
NN
N
N
N
N
O 2 N NO 2
O 2 N NO 2
128
(HNTP)
129
(TNBT)
127
(C-DNAT)
Figure 7.48
Thermodynamic calculations conducted at Los Alamos National Laboratory also identified
HNTP (128) and TNBT (129) as target molecules likely to exhibit high performance.^75
NN
N
H
H 2 N NO 2
NN
N
H
O 2 N NO 2
130
(ANTZ)
131
(DNTZ)
H 2 O 2 , H 2 SO 4
Figure 7.49
Baryshnikov and co-workers^76 synthesized some nitro-substituted 1,2,3-triazoles using an
ingenious cycloaddition reaction between sodium azide and 1,1-dinitroethene; the latter pre-
paredin situfrom a number of precursors including 2,2-dinitroethyl acetate (Section 1.10.2.3).