Organic Chemistry of Explosives

312 N-Heterocycles

4-Amino-5-nitro-1,2,3-triazole (ANTZ) (130), an explosive showing high thermal stability, has

been synthesized via this route; the reaction of sodium azide, acetaldehyde and 2,2-dinitroethyl

acetate forming 4-methyl-5-nitro-1,2,3-triazole, which on conversion of the methyl group to

an amino group yields ANTZ (130). Treatment of ANTZ (130) with hydrogen peroxide in

sulfuric acid yields 4,5-dinitro-1,2,3-triazole (DNTZ) (131).

NO 2

O 2 N

OAc

OAc

NO 2

NO 2

N

NNNN

H

N

O 2 N NO 2

H

132

MeOH, NaN 3

133

(DNBT)

Figure 7.50

Baryshnikov and co-workers^77 used the same methodology for the synthesis of 5,5’-dinitro-

4,4’-bis(1,2,3-triazole) (133) (DNBT) from 1,1,4,4-tetranitro-2,3-butanediol diacetate (132)

in the presence of sodium azide.

N

N

N

NO 2

Si(CH 3 ) 3

(CH 3 ) 3 Si C (CH 3 ) 3 SiN 3

135

+

134

136

C NO 2

Figure 7.51

Gilardi and co-workers^78 reported a synthesis of 4-(trimethylsilyl)-5-nitro-1,2,3-triazole

(136) via a cycloaddition between 1-nitro-2-(trimethylsilyl)acetylene (134) and trimethylsilyl

azide (135). This may provide a route to 4,5-dinitro-1,2,3-triazole via nitrodesilylation or lead

to the synthesis of 4-amino-5-nitro-1,2,3-triazole, an isomer of ANTA.

NN

N

N

N

NO 2

NO 2

138

K

N

N

N

NN

O 2 N NO 2

137 K

Figure 7.52

The two energeticN-nitroimide explosives (137) and (138) have been prepared from 1,2,3-

triazole and 1,2,4-triazole respectively.^79 ,^80 These and otherN-nitroimide-based energetic

compounds are discussed in more detail in Section 6.11.3.

7.4.2 Triazolones

3-Nitro-1,2,4-triazol-5-one (NTO) (140) is prepared from the nitration of 1,2,4-triazol-5-one

(139) under a variety of conditions; the latter prepared from the condensation of semicarbazide