Conjugation and thermally insensitive explosives 179
coupling of styphnyl chloride (106) with two equivalents of picryl chloride (87).^300 NONA
exhibits extremely high thermal stability (m.p. 440–450◦C with decomposition).
Cl
NO 2
Cl
NO 2
106
O 2 N O 2 N
O 2 N
O 2 N
O 2 N
Cl
NO 2
NO 2
87
NO 2
NO 2
NO 2
NO 2
NO 2
NO 2
+^2
158
(NONA)
Electrolytic
Cu powder,
PhNO 2 , 210 °C
Figure 4.70
Polynitropolyphenylene (PNP) (159), which is a polymeric explosive, exhibits high ther-
mal stability and possesses a low sensitivity to friction and impact. This polymeric mixture,
synthesized^301 from the reaction of styphnyl chloride (106) with copper powder in nitroben-
zene, has found use as a thermally stable binder in pyrotechnic compositions.^302 ,^303
Cl
NO 2
Cl
NO 2
106
O 2 N
Activated
Cu powder,
PhNO 2 , 210 °C
NO 2
O 2 N NO 2
n
159
n = 11 - 19
Figure 4.71
Similar routes have been used for the synthesis of other polynitrophenylenes. 1,3,5-
Tris(2,4,6-trinitrophenyl)-2,4,6-trinitrobenzene (160) is synthesized from the reaction of 1,3,5-
trichloro-2,4,6-trinitrobenzene with three equivalents of picryl chloride in the presence of ac-
tivated copper powder in refluxing mesitylene.^304 2,2′′,4,4′,4′′,6,6′,6′′-Octanitro-m-terphenyl
(161) has been synthesized from picryl chloride and 1,3-dichloro-4,6-dinitrobenzene.^305
O 2 N NO 2
O 2 N O 2 N
O 2 N
O 2 N
O 2 N
O 2 N O 2 N
NO 2
NO 2
NO 2 NO 2
NO 2
160
NO 2
NO 2
NO 2
NO 2
NO 2
NO 2
161
Figure 4.72