Furazan hydrazone energetic compound and synthesis method thereof

Abstract

The invention discloses a furazan hydrazone energetic compound and a synthesis method thereof. The preparation method comprises the following steps: reacting trans-butenal with sodium nitrite to obtain 3-methyl-4-formyl-2-furoxan, reacting the 3-methyl-4-formyl-2-furoxan with a sodium nitrite solution and a stannous chloride dihydrate in the presence of hydrogen chloride gas to obtain 3-hydrazino-4-amino-1, 2, 4-triazole hydrochloride, and carrying out column chromatography on the 3-hydrazino-4-amino-1, 2, 4-triazole hydrochloride to obtain 3-methyl-4-amino-1, 2, 4-triazole. And then, carrying out condensation reaction with 3-methyl-4-formyl-2-furazan to obtain a target product. The density is 1.610 g / cm < 3 >, the theoretical detonation velocity is 7677 m / s, the detonation pressure is 21.0 GPa and is close to that of 2, 4, 6-trinitrotoluene (TNT, the detonation velocity is 6881 m / s, and the detonation pressure is 19.5 GPa), the test friction sensitivity is about 360 N, the impact sensitivity is greater than 40 J and is lower than that of TNT (352N, 15J), and the method for synthesizing the furazan hydrazone energetic compound is simple to operate, high in yield and high in safety.

Description

Technical Field

[0001] The invention belongs to the field of energetic materials and relates to an oxidized furazanhydrazone energetic compound and a synthesis method thereof. Background Art

[0002] Nitrogen-rich heterocyclic compounds are an important new class of high energy density materials (HEDM) because they are generally characterized by high density and high enthalpy of formation. Among all five-membered heterocyclic rings, oxadiazoles have attracted widespread attention due to the fact that they contain oxygen atoms, which can increase the oxygen content and improve the oxygen balance, thereby improving the performance of the compound. There are five forms of oxadiazole: 1,2,4-oxadiazole, 1,2,5-oxadiazole (furazan), 1,3,4-oxadiazole, 1,2,3-oxadiazole, and 1,2,5-oxadiazole-2-oxy (furazan oxide). The furazan ring has a high positive enthalpy of formation (219 kJ mol -1 ) has potential for application in the fields of propellants and explosives. In addition, furazan oxide is an N-oxidized derivative of furazan, which further improves the oxygen balance and formation enthalpy of the furazan ring skeleton (226 kJ mol -1 ). Studies have shown that by introducing an oxidized furazan ring into the molecular skeleton, the molecular density can be increased by about 0.06-0.08 g cm -3 , the detonation velocity increases by about 300 m s -1 Therefore, a large number of energetic compounds containing furazan oxide have been studied, and the modification strategy of combining furazan oxide with other nitrogen-rich heterocyclic skeletons is one of the more active research directions in the synthesis of energetic materials.

[0003] In recent years, two energetic materials based on furazan oxide skeletons have been synthesized. For example, the tricyclic compound bis(nitrofurazan) (A) furazan oxide has excellent detonation performance (D = 8930 m s -1 ). Another example, 3,3'-dinitro-4,4'-azofurazan (B), showed a high density (2.0 g cm -3 ) and excellent detonation performance (D = 10000ms -1 ), both significantly better than RDX. Unfortunately, these two compounds have high impact sensitivity (A: 3J; B: <1J). Summary of the invention

[0004] The present invention aims to provide an oxidized furazanhydrazone energetic compound and a synthesis method thereof.

[0005] The technical solution to achieve the purpose of the present invention is: an oxidized furazanhydrazone energetic compound having the following structure:

[0006]

[0007] The method for synthesizing the above compound comprises:

[0008] (1) a step of preparing 3-methyl-4-formyl-2-furoxan (2) by reacting trans-crotonaldehyde with sodium nitrite,

[0009]

[0010] (2) a step of reacting 3,5-diaminotriazole with a sodium nitrite solution and stannous chloride dihydrate under hydrogen chloride gas conditions to obtain 3-hydrazino-4-amino-1,2,4-triazole hydrochloride (4),

[0011]

[0012] (3) a step of reacting 3-hydrazino-4-amino-1,2,4-triazole hydrochloride (4) with 3-methyl-4-formyl-2-oxidofuroxan (2) to obtain the final product 3-amino-5-(3-methyl-4-oxidofuroxanyl)-methylenehydrazino)-1,2,4-triazole (5),

[0013]

[0014] Preferably, in step (1), the molar ratio of trans-crotonaldehyde to sodium nitrite is 1:4.

[0015] Preferably, in step (1), the reaction is carried out in the presence of glacial acetic acid as a solvent, the reaction temperature is room temperature, and the reaction time is more than 12 hours.

[0016] Preferably, in step (2), the molar ratio of 3,5-diaminotriazole to sodium nitrite and stannous chloride dihydrate is 2:1:2.

[0017] Preferably, in step (2), the reaction temperature is 80±5° C. and the reaction time is more than 2 h.

[0018] Preferably, in step (3), the molar ratio of 3-hydrazino-4-amino-1,2,4-triazole hydrochloride to 3-methyl-4-formyl-2-furoxan is 1:1.

[0019] Preferably, in step (3), the reaction is carried out in the presence of anhydrous ethanol as a solvent, the reaction temperature is reflux temperature, and the reaction time is more than 24 hours.

[0020] Compared with the prior art, the advantages of the present invention are:

[0021] (1) The reaction steps of the present invention are simple, the experimental process is safe and efficient, and meets the conditions for scale-up production.

[0022] (2) The target energetic compound obtained by the present invention has good detonation performance, and the detonation velocity of 3-amino-5-(3-methyl-4-oxyfuroxanyl)-methylenehydrazine)-1,2,4-triazole can reach 7677ms -1 The explosion pressure can reach 21.0GPa, which is similar to that of TNT. Its actual impact sensitivity is greater than that of RDX and TNT, and it has the potential to be used as a high-performance insensitive material. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the H NMR spectrum of 3-hydrazino-4-amino-1,2,4-triazole hydrochloride.

[0024] Figure 2 This is the carbon NMR spectrum of 3-hydrazino-4-amino-1,2,4-triazole hydrochloride.

[0025] Figure 3 This is the H NMR spectrum of 3-amino-5-(3-methyl-4-oxidofuroxanyl)-methylenehydrazine)-1,2,4-triazole.

[0026] Figure 4 This is the NMR carbon spectrum of 3-amino-5-(3-methyl-4-oxidofuroxanyl)-methylenehydrazine)-1,2,4-triazole.

[0027] Figure 5 This is the crystal structure diagram of 3-amino-5-(3-methyl-4-oxidofuroxanyl)-methylenehydrazine)-1,2,4-triazole. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the embodiments.

[0029] Embodiment 1:

[0030] Trans-butylene aldehyde (5.91 ml, 71 mmol) was added to glacial acetic acid (20 ml), and an aqueous solution of NaNO2 (17.2 g, 0.285 mmol) (100 ml) was added, and the resulting solution was stirred at 25° C. for 12 h. The reaction mixture was neutralized with NaHCO3, extracted 3 times with CH2Cl2, and the organic phases were combined, washed with saturated NaCl solution, dried over anhydrous magnesium sulfate, concentrated, and then recrystallized with petroleum ether (5 ml), dried, and 3-methyl-4-formyl-2-furoxan was obtained in a yield of 45%.

[0031] Embodiment 2:

[0032] Weigh 10g (100.1mmol) of 3,5-diamino-1,2,4-triazole into a three-necked round-bottom flask, add 200ml of 10mol / L hydrochloric acid, and cool to 0°C in an ice bath. Under stirring conditions, add 25ml of sodium nitrite solution dropwise to the hydrochloric acid solution of 3,5-amino-1,2,4-triazole to carry out a diazotization reaction; weigh 22.6g (100mmol) of stannous chloride dihydrate, add it to the reaction solution within a period of not less than 1.5h to carry out a reduction reaction of the diazonium salt, continue stirring the reaction for 1h, heat to 80°C, filter the reaction solution hot, and pass hydrogen chloride gas into the saturated reaction solution, and a white solid precipitates; then filter with suction, wash with anhydrous ethanol and anhydrous methanol in turn, and dry the filter cake to obtain 11.5g of white powder with a yield of 63%. Its H NMR spectrum and C NMR spectrum are shown respectively. Figure 1 and Figure 2 .

[0033] 1 H NMR (500MHz, DMSO-d6): δ (ppm) 9.79 (s, 1H). 13 C NMR (125MHz, DMSO-d6): δ (ppm) 151.7, 150.7.C, H, N analysis (%): C2H7N6 + (115.12), calculated result: C 20.87, H6.13, N 70.00; found: C 20.88, H 6.14, N 70.02.

[0034] Embodiment 3:

[0035] Take 1.89g of 3-hydrazine-4-amino-1,2,4-triazole hydrochloride in a 50ml three-necked flask, add 25mL of anhydrous ethanol, add 1.54g of 3-methyl-4-formyl-2-furoxan in batches under stirring, raise the temperature to reflux and react for 24h. Cool and a white precipitate will precipitate. Filter and wash with cold ethanol to obtain 2.13g of a white product with a yield of 89%. Its H NMR spectrum and C NMR spectrum are shown as follows: Figure 3 and Figure 4 , the crystal structure is shown in Figure 5 .

[0036] 1 H NMR (500MHz, DMSO-d6): δ (ppm) 12.71 (s, 1H), 8.25 (s, 1H), 2.40 (s, 3H). 13C NMR (125MHz, DMSO-d6): δ (ppm) 154.2, 151.5, 149.3, 131.7, 112.1, 10.1. IR (KBr): 3248.91, 2650.85, 16 89.73,1571.82,1445.39,1366.60,1120.58,989.92,984.06,849.52,816.87,789.17,699.04,654.68cm -1 .C, H, N analysis (%): C6H8N8O2 (224.08), calculated result: C 32.15, H 3.60, N 49.98; found: C 32.28, H 3.46, N 49.33.

[0037] The compound density is 1.610g / cm 3 The BKW state equation predicts that the theoretical detonation velocity of the product is 7677m / s, and the theoretical detonation pressure is 21.0GPa, which is close to 2,4,6-trinitrotoluene (TNT, detonation velocity: 6881m / s, explosion pressure: 19.5GPa). The tested friction sensitivity is about 360N, and the impact sensitivity is greater than 40J, which is lower than TNT (352N, 15J).

Claims

1. An oxidized furazanhydrazone energetic compound, characterized in that: It has the following structure:

2. A method for synthesizing an oxidized furazone energetic compound, characterized in that: include: (1) a step of preparing 3-methyl-4-formyl-2-furoxan (2) by reacting trans-crotonaldehyde with sodium nitrite, (2) a step of reacting 3,5-diaminotriazole with a sodium nitrite solution and stannous chloride dihydrate under hydrogen chloride gas conditions to obtain 3-hydrazino-4-amino-1,2,4-triazole hydrochloride (4), (3) a step of reacting 3-hydrazino-4-amino-1,2,4-triazole hydrochloride (4) with 3-methyl-4-formyl-2-oxidofuroxan (2) to obtain the final product 3-amino-5-(3-methyl-4-oxidofuroxanyl)-methylenehydrazino)-1,2,4-triazole (5), 3. The method according to claim 2, characterized in that In step (1), the molar ratio of trans-crotonaldehyde to sodium nitrite is 1:

4.

4. The method according to claim 2, characterized in that In step (1), the reaction is carried out in the presence of glacial acetic acid as a solvent, the reaction temperature is room temperature, and the reaction time is more than 12 hours.

5. The method according to claim 2, characterized in that In step (2), the molar ratio of 3,5-diaminotriazole to sodium nitrite and stannous chloride dihydrate is 2:1:

2.

6. The method according to claim 2, characterized in that In step (2), the reaction temperature is 80 ± 5 o C, the reaction time is more than 2h.

7. The method according to claim 2, characterized in that In step (3), the molar ratio of 3-hydrazino-4-amino-1,2,4-triazole hydrochloride to 3-methyl-4-formyl-2-furoxan is 1:

1.

8. The method according to claim 2, characterized in that In step (3), the reaction is carried out in the presence of anhydrous ethanol as a solvent, the reaction temperature is reflux temperature, and the reaction time is more than 24 hours.

9. Use of the oxidized furazanhydrazone energetic compound as claimed in claim 1 as an insensitive explosive.

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