Organic Chemistry of Explosives

5-MEMBERED RINGS – 4N 315

Agrawal and co-workers reported the synthesis of two tetrazole-based explosives, namely, 5-

picrylamino-1,2,3,4-tetrazole^94 (PAT) (149) and 5,5’-styphnylamino-1,2,3,4-tetrazole^95 (SAT)

(150) from the reaction of 5-amino-1,2,3,4-tetrazole (148) with picryl chloride and styphnyl

chloride respectively. These explosives have been studied for their thermal and explosive

properties. The thermal stability of SAT (exotherm peak at 123◦C) is lower than PAT (exotherm

peak at 185◦C), which is possibly attributed to the decreased electron-withdrawing power of

the picryl group by being attached to two tetrazole units. PAT and SAT have calculated VODs

of 8126 m/s and 8602 m/s respectively.^95

HN

NO 2

NO 2

151

O 2 N

N

N

HN N

H 2 N NH 2

H

N

H

N

NO 2

O 2 N NO 2

HNN

NN NN

N NH

150

(SAT)

Figure 7.58

The reaction of 5-aminotetrazole with 3,5-diamino-2,4,6-trinitrofluorobenzene generates

the energetic tetrazole (151).^96

N

N

N N

N

N

N

NN

H 2 N N

H 2 N

O

H

H

N

N

H

H

N N

N

N

N

N

N N

N

N

NO 2

155

NO 2

NaBH 4 HNO 3

Ac 2 O

+

152 153

154

O

Figure 7.59

The bis-nitramine (155) has been prepared from the reaction of 1,5-diaminotetrazole (152)

with glyoxal, followed by reduction of the resulting fused heterocycle (153) with sodium

borohydride and subsequentN-nitration of the piperazine nitrogens of (154).^97

N

N

N

N

N

N

N

N

N

2 X

156

N

Figure 7.60

Salts of azotetrazole (156) are energetic compounds, the guanidinium and methylammonium

salts finding use as gas generators when mixed with inorganic oxidizers.^98 ,^99 Thiele^100 ,^101