Nitrogen-rich fused ring energetic compound and preparation method thereof

Abstract

The nitrogen-rich condensed ring energetic compound has the advantages that firstly, the nitrogen-rich condensed ring energetic compound is high in nitrogen content and energy density, and various performance indexes of the nitrogen-rich condensed ring energetic compound are superior to those of lead Stefan and DDNP; on the second aspect, the invention provides a preparation method of the nitrogen-rich fused ring energetic compound, according to the method, 3, 5, 6-trichloro-1, 2, 4-triazine is taken as a raw material, the energetic compound is obtained through two-step reaction of ammonification and azidation, the operation is simple and convenient, the reliability is high, the yield is high, the stability is good, the method is suitable for large-scale production, the raw material is easy to obtain, and the production cost is low.

Description

Technical Field

[0001] The present invention belongs to the technical field of energetic materials, and in particular relates to a nitrogen-rich fused-ring energetic compound and a preparation method thereof. Background Art

[0002] Primers are sensitive explosives that can generate heat and burn under weak external excitation energy, such as heat, electricity, light, mechanical, impact, and friction, and can quickly detonate and detonate. They are a type of energetic material. Primers have high sensitivity and a short detonation growth period. The detonation wave generated by the detonation is used to detonate the explosive, so they are also called primary explosives. Primers are the starting charge of explosive devices and are loaded in various detonating devices. They are widely used in pyrotechnic explosive devices. They are the filling agent of detonators and are usually used to detonate explosives. According to the composition, they can be divided into single explosives, mixed explosives and double salt explosives; according to the excitation method, they can be divided into piercing explosives, percussion explosives, friction explosives and conductive explosives.

[0003] A detonator should have certain temperature and humidity resistance, sufficient detonation ability, appropriate sensitivity, qualified stability, good charging process performance and other basic requirements; in addition, it is also required that the raw materials for preparation are cheap and easy to obtain, the production process is simple, the operation is safe, and environmental pollution is avoided, and it is green and environmentally friendly. The most commonly used detonators include lead azide, lead stevenate and 2,4-dinitrodiazophenol (DDNP), etc. However, the industrial application of the above detonators is prone to environmental pollution and health threats, and is listed as a "substance of high concern". Therefore, new environmentally friendly detonators have become a research trend of energetic compounds.

[0004] Polynitro nitrogen-rich energetic derivatives have the characteristics of high energy, high density and high formation enthalpy due to the presence of a large number of CN bonds and NN bonds in their molecular structure. At the same time, their decomposition products are pollution-free nitrogen gas, and they are considered to be substitutes for high-energy materials. Although polynitro nitrogen-rich compounds have good density and detonation properties, they are generally less stable. For example, 1,1'-dinitroamino-5,5'-tetrazole dipotassium salt (K2DNABT) has an extremely short deflagration to detonation (DDT) behavior and is highly sensitive to stimuli such as friction, impact and electrostatic discharge. However, its synthesis steps are complex (6-step reaction), the total yield is low (<14.7%), and the mechanical sensitivity is extremely high (IS=1J, FS≤1N), which limits its further application. Therefore, while increasing the nitrogen content of energetic materials, further improving the stability of energetic materials is the focus of current research.

[0005] In summary, it is of great significance to develop new nitrogen-rich energetic materials with simple synthesis steps, good stability and green and pollution-free. Summary of the invention

[0006] In the first aspect of the present invention, there is provided a 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine nitrogen-rich fused ring energetic compound; the fused ring molecular structure contains an N5 chain, an azide group and an amino structure, and its chemical structure is shown in Formula I:

[0007]

[0008] The second aspect of the present invention provides a method for preparing a 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine nitrogen-rich fused ring energetic compound, comprising the following steps:

[0009] Step 1, using 3,5,6-trichloro-1,2,4-triazine and an aminating agent as raw materials, dissolving 3,5,6-trichloro-1,2,4-triazine in a polar solvent, then adding an aminating agent to react, separating the solid phase, washing, and drying to obtain compound A; the structural formula of compound A is shown in formula II:

[0010]

[0011] Step 2, dissolving compound A in a mixed solvent, reacting with an azidating agent for nucleophilic substitution reaction, separating the solid phase, washing and drying, and obtaining a 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine nitrogen-rich fused ring energetic compound; the fused ring molecular structure contains an N5 chain, an azido group and an amino structure, and its chemical structure is shown in Formula I:

[0012]

[0013] As a preferred embodiment, the polar solvent in step 1 is one or more of acetonitrile and ethanol.

[0014] As a preferred embodiment, the amination reagent in step 1 is aqueous ammonia.

[0015] As a preferred embodiment, in step 1, the molar ratio of 3,5,6-trichloro-1,2,4-triazine to the aminating agent is 1:1.2 to 1:1.5, the reaction time is 12 hours to 24 hours, the temperature when adding the aminating agent is 0°C to 2°C, and the reaction temperature is 18°C ​​to 20°C.

[0016] As a preferred embodiment, the solid phase washing solvent in step 1 is deionized water.

[0017] As a preferred embodiment, the azidation reagent in step 2 is one or more of sodium azide, trimethylsilyl azido, and diphenylphosphoazide.

[0018] As a preferred embodiment, the mixed solvent in step 2 is one or more of a mixture of acetone and water and a mixture of acetonitrile and water.

[0019] As a preferred embodiment, in step 2, the molar ratio of compound A to the azidation reagent is 1:2.4 to 1:3.0, the reaction time is 18 hours to 36 hours, and the reaction temperature is 75°C to 85°C.

[0020] As a preferred embodiment, the solid phase washing solvent in step 2 is deionized water.

[0021] The third aspect of the present invention provides the use of the 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine in energetic materials. The energetic material is used as a new type of nitrogen-rich energetic material in the field of green explosives.

[0022] Through the above technical solution, the present invention produces the following beneficial effects:

[0023] (1) The 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine provided by the present invention has a high nitrogen content and a high energy density. Its impact sensitivity is 12 J, its friction sensitivity is 48 N, and its detonation velocity reaches 8761 m s -1 , the explosion pressure reaches 29.3GPa, and the above performance indicators are better than lead stevenate and DDNP.

[0024] (2) The present invention uses 3,5,6-trichloro-1,2,4-triazine as a raw material, and obtains the energetic compound through a two-step reaction of ammoniation and azidation. The method is simple to operate, has high reliability, high yield, good stability, is suitable for large-scale production, and its raw materials are easy to obtain and the production cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is the carbon NMR spectrum of compound A obtained in Example 1;

[0026] Figure 2 is the hydrogen nuclear magnetic resonance spectrum of compound A obtained in Example 1;

[0027] Figure 3 is the carbon NMR spectrum of compound I obtained in Example 1;

[0028] Figure 4 is the hydrogen nuclear magnetic resonance spectrum of compound I obtained in Example 1;

[0029] Figure 5 The single crystal molecular structure diagram of Compound I obtained in Example 1;

[0030] NMR Figure 1-4 The horizontal axis represents the chemical shift, and the vertical axis represents the peak intensity. DETAILED DESCRIPTION

[0031] In order to make the technical solution of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments. The embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by ordinary technicians in the field according to the above invention content still belong to the scope of protection of the present invention.

[0032] Example 1

[0033] Step 1: Add 15.0 g (0.081 mol) of 3,5,6-trichloro-1,2,4-triazine to 80 mL of acetonitrile; at 0°C, add 13.6 ml of 28% ammonia water, raise the temperature to 20°C, and react for 12 hours; after the reaction, filter under reduced pressure, wash with water and dry to obtain 12.2 g of a white solid, which is solid product A.

[0034] The obtained solid product A was subjected to elemental analysis, and the mass percentage of each element was found to be: C was 21.78%, H was 1.20%, Cl was 42.95%, and N was 34.07%.

[0035] The obtained solid product A was subjected to NMR analysis. In addition to the water peak and solvent peak, there was only one group of amino peaks, which was consistent with the structural characteristics. The NMR analysis results are shown in Figure 1 , Figure 2 .

[0036] Step 2: Weigh 1.65 g (0.01 mol) of solid product A, add the solid product A to a mixed solution of 30 mL of acetone and water (the volume ratio of acetone to water is 5:1) at room temperature, then add 2.76 g of azidotrimethylsilylating agent (0.024 mol) to the reaction system in batches. After the addition is complete, gradually heat the mixture to reflux and react for 24 hours. After the reaction is completed, filter under reduced pressure, wash with deionized water and dry to obtain 1.57 g of white solid product I, which is 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine.

[0037] Elemental analysis of the obtained solid product I showed that the mass percentage of each element was: C was 20.31%, H was 1.17%, and N was 78.52%, which was consistent with the mass percentage of the elements in the compound 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine (C: 20.23%, H: 1.13%, N: 78.64%).

[0038] The solid product I was subjected to NMR analysis and the NMR chemical shifts were assigned. It was found that there was only one group of amino peaks besides the water peak and solvent peak, which was consistent with the structural characteristics. The NMR analysis results are shown in Figure 3 , Figure 4 .

[0039] The obtained solid product I was subjected to crystal structure analysis, and combined with the crystal structure diagram, it was proved that the prepared solid product I was a 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine nitrogen-rich fused ring energetic compound. The crystal structure diagram is shown in Figure 5 .

[0040] The above structural identification data confirmed that the obtained solid product I was 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine.

[0041] Example 2

[0042] Step 1: Add 10.0 g (0.081 mol) of 3,5,6-trichloro-1,2,4-triazine to 80 mL of ethanol, add 9.1 ml of 28% ammonia water at 0°C, heat to 20°C, and react for 12 hours; after the reaction, filter under reduced pressure, wash with water and dry to obtain 7.6 g of white solid, which is solid product A.

[0043] The obtained solid product A was subjected to elemental analysis, and the mass percentage of each element was found to be: C was 21.75%, H was 1.24%, Cl was 42.91%, and N was 34.10%.

[0044] The obtained solid product A was subjected to NMR analysis. In addition to the water peak and the solvent peak, there was only one group of amino peaks, which was consistent with the structural characteristics. The NMR analysis results were consistent with those in Example 1. Figure 1 , Figure 2 .

[0045] Step 2: Weigh 3.30g (0.02mol) of solid product A, add it to a mixed solution of 60mL acetonitrile and water (volume ratio of acetone to water is 5:1) at room temperature, then add 13.76g diphenylphosphoryl azide (0.050mol) to the reaction system in batches, after the addition is complete, gradually raise the temperature to reflux state, and react for 24h. After the reaction is completed, 3.20g of white solid product I is obtained by vacuum filtration, washing with deionized water and drying, which is 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine.

[0046] The obtained solid product I was subjected to elemental analysis, and the mass percentage of each element was found to be: C was 20.33%, H was 1.19%, and N was 75.48%.

[0047] The solid product I obtained was subjected to NMR analysis. In addition to the water peak and solvent peak, there was only one group of amino peaks, which was consistent with the structural characteristics. The NMR analysis results were consistent with those of Example 1. Figure 3 , Figure 4 .

[0048] The obtained solid product I was subjected to crystal structure analysis, and combined with the crystal structure diagram, it was proved that the prepared product was a nitrogen-rich fused ring energetic compound of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine. The crystal structure was consistent with that of Example 1, see Figure 5 .

[0049] The above structural identification data confirmed that the obtained solid product I was 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine.

[0050] Example 3

[0051] EXPL05 software (version 6.05) was used to calculate the detonation velocity and detonation pressure of the nitrogen-rich energetic compound of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine prepared in Example 1 to predict the detonation performance; a differential calorimeter was used to measure the decomposition temperature of the nitrogen-rich energetic compound of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine prepared in Example 1. The specific results are shown in Table 1.

[0052] Table 1: Performance data of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine nitrogen-rich energetic compounds prepared in Example 1

[0053]

[0054] Where [a] represents the thermal decomposition temperature in [℃]; [b] represents the density in [g·cm 3 ]; [c] represents oxygen balance (C0), in [%]; [d] represents molar enthalpy of formation, in [kJ·mol 1 ]; [e] represents the detonation velocity, the unit is [m·s 1 ]; [f] represents explosion pressure, the unit is [GPa]; [g] represents impact sensitivity, the unit is [J]; [h] represents friction sensitivity, the unit is [N].

[0055] EXPL05 software (version 6.05) was used to calculate the detonation velocity and detonation pressure of the nitrogen-rich energetic compound 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine prepared in Example 2 to predict the detonation performance. A differential calorimeter was used to measure the decomposition temperature of the nitrogen-rich energetic compound 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine prepared in Example 2. The specific results were basically consistent with those in Example 1.

[0056] The above test results show that according to the preparation method shown in Examples 1 and 2, a nitrogen-rich energetic compound of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine can be prepared, and the compound has excellent performance, high nitrogen content, high energy density, and its impact sensitivity, friction sensitivity, detonation velocity, and detonation pressure performance indicators are better than lead stevenate and DDNP.

[0057] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A nitrogen-rich fused-ring energetic compound, characterized in that: The nitrogen-rich fused ring energetic compound is 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine, and its chemical structure is shown in Formula I:

2. A method for preparing the nitrogen-rich fused-ring energetic compound as claimed in claim 1, characterized in that: The following steps are involved: Step 1, using 3,5,6-trichloro-1,2,4-triazine and an aminating agent as raw materials, dissolving 3,5,6-trichloro-1,2,4-triazine in a polar solvent, then adding an aminating agent to react, separating the solid phase, washing, and drying to obtain compound A; the structural formula of compound A is shown in formula II: Step 2, dissolving compound A in a mixed solvent (the volume ratio of organic solvent to water is 5:1), reacting with an azidating agent for nucleophilic substitution, separating the solid phase, washing and drying, and obtaining 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine.

3. The method for preparing the nitrogen-rich fused-ring energetic compound according to claim 2, characterized in that: In step 1, the polar solvent is one or more of acetonitrile and ethanol.

4. The method for preparing the nitrogen-rich fused-ring energetic compound according to claim 3, characterized in that: In the step 1, the amination reagent is aqueous ammonia.

5. The method for preparing the nitrogen-rich fused-ring energetic compound according to claim 4, characterized in that: In the step 1, the molar ratio of 3,5,6-trichloro-1,2,4-triazine to the aminating agent is 1:1.2 to 1:1.5, the reaction time is 12 hours to 24 hours, the temperature when adding the aminating agent is 0°C to 2°C, and the reaction temperature is 18°C ​​to 20°C.

6. The method for preparing the nitrogen-rich fused-ring energetic compound according to claim 5, characterized in that: In step 2, the azidation reagent is one or more of sodium azide, trimethylsilyl azido, and diphenylphosphoazide.

7. The method for preparing the nitrogen-rich fused-ring energetic compound according to claim 6, characterized in that: The mixed solvent in step 2 is one or more of a mixture of acetone and water and a mixture of acetonitrile and water.

8. The method for preparing the nitrogen-rich fused-ring energetic compound according to claim 2, characterized in that: In the step 2, the molar ratio of compound A to the azidation reagent is 1:2.4 to 1:3.0, the reaction time is 18 hours to 36 hours, and the reaction temperature is 75° C. to 85° C.

9. Use of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine as claimed in claim 1 in energetic materials.

10. Use of 6-azidotetrazolyl[1,5-b][1,2,4]triazine-7-amine as claimed in claim 1 in detonating explosives.

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