Organic Chemistry of Explosives

5-Membered rings – 2N 301

N

O

N

H 2 N

N

H

H

N

N

H

H

N

N

O

N N

O

N

NO 2 NO 2

NO 2 NO 2

OO

HH

+

HCl (aq) TFAA, HNO 3

45

N

N

N

N

N

O

N N

O

N

46

24

NH 2

Figure 7.18

Moore and Willer^27 –^29 reported the synthesis of some nitramine explosives containing a

furazan ring fused to a piperazine ring. The tetranitramine (46) is synthesized from the con-

densation of 3,4-diaminofurazan (DAF) (24) with glyoxal under acidic conditions followed by

N-nitration of the resulting heterocycle (45). The calculated performance for the tetranitramine

(46) is very high but the compound proves to be unstable at room temperature. Instability is a

common feature of heterocyclic nitramines derived from the nitration of aminal nitrogens.

N

N N

O

N N

N

NO 2 NO 2

NO 2 NO 2

47

NO 2

48

N

O

N N

O

N N

N

H NO^2

NO 2

Figure 7.19

Sun and co-workers^30 synthesized the furazans (47) and (48) from the nitration of the

products derived from the reaction of 3,4-diaminofurazan (DAF) (24) withN,N′-diformyl-

4,5-dihydroxyimidazole and 4,5-dihydroxyimidazolid-3-one, respectively.

N

H

49

H

N NOH

NOH N

H

50

H

N

N

O

N

N

N

N

O

N

NO 2

TFAA, HNO 3

NaOH,

HOCH 2 CH 2 OH

150 °C

NO 2

51

Figure 7.20

Willer^31 synthesized the bis-nitramine (51) via the cyclodehydration of the dioxime (49)

with sodium hydroxide in ethylene glycol followed by subsequent nitration of the resulting

heterocycle (50).

N

N

R

R

N

O

N N

O

N

52, R = H

53, R = NO 2

54, R = picryl

Figure 7.21

Tselinskii and co-workers^32 reported the synthesis of the bis(furazano)piperazine (52) and

its nitration to the energetic bis-nitramine (53) (calculated VOD∼9700 m/s) with nitrogen