Organic Chemistry of Explosives

Azetidines – 1,3,3-trinitroazetidine 265

paraformaldehyde in 80 % aqueous sulfuric acid yields octahydro-1,3,4,6-tetranitro-3a,3b,6a,

6b-cyclobuta[1,2-d:3,4-d′]diimidazole (11).

N

NN

N

12

NOON

ON NO

NO 2

NO 2

O 2 N

O 2 N

Me Me

Me Me

N

NN

N

13

Me Me

Me Me

Figure 6.3

The tetranitrosamine (12) and the tetranitramine (13) are also synthesized from the bis-urea

(8), although these are less energetic and have less favourable oxygen balances than (9), (10)

and (11).^2

6.3 Azetidines – 1,3,3-trinitroazetidine (TNAZ)

1,3,3-Trinitroazetidine (TNAZ) (18) is the product of a search for high performance explosives

which also exhibit desirable properties, such as high thermal stability and low sensitivity to

shock and impact. TNAZ is a powerful explosive which exhibits higher performance than RDX

and HMX in the low vulnerability ammunition XM-39 gun-propellant formulations, while also

showing low sensitivity to impact and good thermal stability.^3 TNAZ has a convenient low

melting point (101◦C) which allows for the melt casting of charges. TNAZ is also fully miscible

in molten TNT. These favourable properties have meant that TNAZ has been synthesized by

numerous routes^4 −^9 and is now manufactured on a pilot plant scale.

Cl

O

t-BuNH 2

N

H OMs

O 2 N

MeSO 2 Cl

Et 3 N

tBu

14

+

1. NaOH (aq)


2. NaNO 2 , Na 2 S 2 O 8
   K 3 Fe(CN) 6 , 60 %

HNO 3 , Ac 2 O

35 %

C 6 H 3 (OH) 3 ,

NaNO 2 ,

MeOH, H 2 O

8%

OH

N

H

tBu

15

N

H

tBu

16

NO 2

N

tBu

17

O 2 N NO 2

N

NO 2

18

(TNAZ)

NO 2

Figure 6.4 Archibald and co-workers route to TNAZ^4