306 N-Heterocycles
NH
NH
NNO 2 O 2 N
O 2 N NO 2NO
N NO
NNONONH
NH
NNO 2 N NNOO O O
N NO
NNONOO ONH
O 2 NO 2 NNONON
ON
O
8990N
ONON
ONOFigure 7.33The incorporation of amino groups into high molecular weight benzofuroxans has been
explored in an attempt to improve thermal stability and lower sensitivity to impact. Some of
these compounds have been specifically designed to exhibit these desirable properties, and
although of high molecular weight, many of these compounds can be synthesized in relatively
few synthetic steps. The synthesis of (88) (calculated VOD∼8570 m/s,d= 1 .92 g/cm^3 )
starts from the condensation ofp-phenylenediamine (84) with two equivalents of styphnyl
chloride (85), tri-nitration of the phenylenediamine rings, displacement of the chloro groups
of (87) with azide nucleophile, followed by thermolysis of the resulting azide.^52 ,^53 Other
complex benzofuroxans prepared by similar routes include the triazine (89)^54 (calculated VOD
∼8630 m/s,d= 1 .90 g/cm^3 , m.p. 231◦C) and the pyridine (90)^55 (calculated VOD∼ 8695
m/s,d= 1 .90 g/cm^3 , m.p. 316◦C).
NN
NNNN NNNO 2 NO 2O 2 N NO 2O 2 NO 2 NO 2 N NO 2NO 2O 2 NO 2 NNNNO 2NON
O
NONONN (^3) N
N 3 N 3
N 3
N
NNN
o-C 6 H 4 Cl 2
91
NN
NN
92
95
(γ-DBBD)
150 °C
93
94
H 2 SO 4
90 % HNO 3
NaN 3 , DMSO
75 °C
90 %
HNO 3
Figure 7.34
N N
NN
NO 2
O 2 N
N
O
N N
O
N
O
O
96
(z-DBBD)
Figure 7.35