Explosive stable to over 500ºC: BTDAONAB

BTDAONAB (N,N'-Bis (1,2,4-triazol-3-yl)-4,4'-diamino-2,2',3,3',5,5',6,6'-octanitroazo-benzene) is among the most thermally stable explosives known. It is stable at up to 550ºC.



The surprising thing is how few specialty chemicals are required. Here is the list of materials used in the synthesis:

chloroform
acetone
ethyl acetate
methanol
oleum (25% SO3 by mass)
nitric acid (98% or higher)
sodium azide
p-chlorobenzoic acid
3-amino-1,2,4-triazole

Since the original journal publication is in password-protected PDF form in an obscure journal, I will manually type out the synthesis instructions here:

4-Chloro-3,5-dinitrobenzoic acid

40 mL of oleum (25%) was transferred carefully to a 250 mL three-necked round-bottomed flask fitted with a mechanical stirrer, dropping funnel and reflux condenser and 36 mL of fuming nitric acid was added drop-wise under stirring and maintaining the temperature = 25-30°C (ice bath cooling). To this nitrating mixture, 4-chlorobenzoic acid (10 g, 63.9 mmol) was added slowly with continuous stirring. After the addition, reaction mixture was heated on a water bath to achieve a temperature of 92-95°C which was maintained for 4 h under continuous stirring. The reaction mixture was allowed to cool to ambient temperature followed by pouring into the crushed-ice. The pale yellow compound, thus obtained, was filtered and washed thoroughly with cold water till it is acid-free. The product was crystallized from ethyl acetate. The yield was 12.8 g (81.2%) and m.p. was 162-63°C.

4-Chloro-3,5-dinitroaniline

20 mL of oleum (25%) was carefully transferred to a three-necked round-bottomed flask fitted with a mechanical stirrer, reflux condenser and dropping funnel followed by the drop-wise addition of 4 mL of concentrated sulfuric acid (98%) To this, 4-chloro-3,5-dinitrobenzoic acid (10 g, 40.56 mmol) was added slowly under continuous stirring. After complete dissolution, 40 mL of chloroform was also added through a dropping funnel and the temperature of the reaction mixture was raised to 35-40° C. Sodium azide (4 g, 61.5 mmol) was added in small portions under vigorous stirring followed by reflux for 4 h. The reaction mixture was allowed to cool and then poured into the crushed ice. The dark yellow product thus obtained was filtered and washed with water till it is acid-free. The product was crystallized from ethyl acetate. The yield was 7.4 g {- 84%) with a mp. of 188-190°C.

4,4'-Dichloro-2,2',3,3',5,5',6,6'-octanitroazobenzene

To a 500 mL three-necked round-bottomed flask fitted with a mechanical stirrer, thermometer pocket and dropping funnel 250 mL of concentrated sulfuric acid (98%) was carefully transferred followed by drop-wise addition of 15 mL fuming nitric acid (98%) under vigorous stirring at 25-30°C (in an ice bath). 4-chloro-3,5-dinitroaniline (10 g, 45.97 mmol) was slowly added to this nitrating mixture while maintaining the same temperature. The temperature of reaction mixture was slowly raised to 85-90°C over approximately one hour and maintained for 2.5 hrs. The reaction mixture was subsequently cooled to ambient temperature and poured into the crushed ice. A light yellow product was obtained, filtered and washed with distilled water till it became acid-free. It was then dried to yield 11.0 g (~38%) with DTA exotherm at 340°C.

N,N'-Bis (1,2,4-triazol-3-yl)-4,4'-diamino-2,2',3,3',5,5',6,6'-octanitroazo-benzene

In a three-necked mund-bottomed flask fitted with a reflux condenser and additional funnel 4,4'-dichloro-2,2', 3,3', 5,5', 6,6 -octanitroazobenzene (5 g, 8.18 mmol) was transferred followed by addition of 100 mL of methanol. 3-amino-1,2,4-triazole (5 g, 41.66 mmol) was added to this slowly with occasional swirling. The reaction mixture was refluxed for 5 h followed by cooling to ambient temperature and pouring into the ice-cooled water. The resulting brown precipitate was allowed to settle overnight. The product was filtered, washed thoroughly with distilled water and dried in a water jacketed oven at 60ºC. The compound was further washed with acetone to remove any impurities and finally air-dried to yield 3.6 g (64%) and DTA exotherm at 550ºC.

[Edited on 2-10-2013 by killswitch]

Quote: Originally posted by killswitch

Since the original journal publication is in password-protected PDF form in an obscure journal...

Quote: Originally posted by Ral123

Thanks, I'm not to good with chemistry. If that 550C is so far beyond it's comfortable temperature, then I can imagine it. Does that mean that TATB(TATNB?) is much more stable then TNB?