A multi-azido-based heterocyclic energetic compound, a preparation method and application thereof

Abstract

The application discloses a multi-azido heterocyclic energetic compound with a structural formula I, and a chemical formula C5N 12 . A preparation method is as follows: 2,4,6-trichloro-5-cyanopyrimidine is reacted with sodium azide in a solvent to obtain the multi-azido heterocyclic energetic compound. The multi-azido heterocyclic energetic compound has good thermal stability and detonation performance, and the calculated detonation pressure of EXPLO5 is 23.6 GPa, and the detonation velocity is 7197 m / s ‑1 .

Description

Technical Field

[0001] This invention relates to an energetic compound, and more particularly to a polyazido-based heterocyclic energetic compound, its preparation method, and its application. Background Technology

[0002] Initiating explosives are a class of explosives that can be detonated by weak stimuli (such as impact, friction, vibration, heating, and static electricity). They are the most sensitive and first-acting agents in pyrotechnics, directly controlling the sensitivity, intensity, and effect of the pyrotechnics. Their role in pyrotechnics is irreplaceable by other energetic materials. Traditional lead-sensitive compounds such as lead stearate (LTNR) and lead azide (LA) are currently the most widely used key components of initiating explosives. These often contain toxic additives such as antimony sulfide and barium nitrate. These initiating explosives have excessively high sensitivity and contain heavy metals, which are harmful to the environment and affect human health. With the development of new initiating technologies for pyrotechnics, traditional initiating explosives can no longer meet the requirements of advanced pyrotechnics. Therefore, there is an urgent need to conduct research on green initiating explosives that are free of lead, mercury, and other heavy metals, have certain stability, and good explosive performance. Summary of the Invention

[0003] Objectives of the Invention: The first objective of this invention is to provide a polyazido-based heterocyclic energetic compound with good detonation performance; the second objective of this invention is to provide a method for preparing the polyazido-based heterocyclic energetic compound; and the third objective of this invention is to provide the application of the polyazido-based heterocyclic energetic compound as a green initiator.

[0004] Technical solution: The polyazido-based heterocyclic energetic compound of the present invention has the chemical formula C5N 12 The structural formula is:

[0005]

[0006] The crystal parameters of the compound are:

[0007] Crystal system: Monoclinic;

[0008] Point group: P21 / c;

[0009] Unit cell parameters: α=γ=90°, β=99.618(6)°;

[0010] Unit cell volume:

[0011] Z = 8.

[0012] The crystal exhibits an exothermic peak between 160 and 215 °C. The decomposition temperature (Tonset) is 168 °C (heating rate 5 °C / min). -1It exhibits a significant melting and endothermic process before thermal decomposition, and has the remarkable exothermic characteristics of energetic compounds.

[0013] The calculated explosion pressure of the compound using EXPLO5 was 23.6 GPa, and the explosion velocity was 7197 m·s. -1 .

[0014] The nitrogen content of the polyazido-based heterocyclic energetic compound is 73.87%.

[0015] The density of the polyazido-based heterocyclic energetic compound is 1.606 g·cm³. -3 .

[0016] The method for preparing the polyazido-based heterocyclic energetic compound of the present invention includes the following steps: reacting 2,4,6-trichloro-5-cyanopyrimidine with sodium azide in a solvent, the synthetic route is as follows:

[0017]

[0018] Preferably, the reaction temperature is 55–60°C and the reaction time is 12–14 h.

[0019] The solvent for the reaction is acetone.

[0020] The molar ratio of 2,4,6-trichloro-5-cyanopyrimidine to sodium azide is 1:3 to 3.5.

[0021] The application of the polyazido-based heterocyclic energetic compound described in this invention as a green initiator.

[0022] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The polyazide-based heterocyclic energetic compound has good thermal stability and detonation performance. The EXPLO5 calculated detonation pressure is 23.6 GPa and the detonation velocity is 7197 m·s. -1 (2) The preparation method is simple and easy to industrialize; (3) The polyazido-based heterocyclic energetic compound is environmentally friendly and can be used as a promising green initiator. Attached Figure Description

[0023] Figure 1 The crystal structure diagram of 2,4,6-triazidopyrimidine-5-carboxynitrile prepared in Example 1 of the present invention (viewing angle perpendicular to the pyrimidine ring plane);

[0024] Figure 2 The crystal structure diagram of 2,4,6-triazidopyrimidine-5-carboxynitrile prepared in Example 1 of the present invention (viewing angle parallel to the pyrimidine ring plane);

[0025] Figure 3 This is a unit cell packing diagram of 2,4,6-triazidopyrimidine-5-carboxynitrile prepared in Example 1 of the present invention;

[0026] Figure 4 The carbon NMR spectrum of 2,4,6-triazidopyrimidine-5-carboxynitrile prepared in Example 1 of this invention (solvent is deuterated dimethyl sulfoxide);

[0027] Figure 5 The infrared spectrum of 2,4,6-triazidopyrimidine-5-carboxynitrile prepared in Example 1 of this invention;

[0028] Figure 6 Differential scanning calorimetry (DSC) of 2,4,6-triazidopyrimidine-5-carboxynitrile prepared in Example 1 of this invention (heating rate 5 °C·min) -1 ). Detailed Implementation

[0029] The technical solution of the present invention will be further described below with reference to the embodiments.

[0030] Example 1

[0031] The method for preparing the polyazido-based heterocyclic energetic compound of the present invention is as follows:

[0032] 2,4,6-trichloro-5-cyanopyrimidine (2.08 g, 10.0 mmol) was dissolved in acetone (25 mL), and sodium azide (1.95 g, 30 mmol) was added. The mixture was refluxed at 55 °C and stirred for 10 h. After cooling to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to give 2,4,6-triazidopyrimidine-5-carboxynitrile (1.89 g), with a yield of 82.8%.

[0033] Example 2

[0034] The method for preparing the polyazido-based heterocyclic energetic compound of the present invention is as follows:

[0035] 2,4,6-trichloro-5-cyanopyrimidine (2.08 g, 10.0 mmol) was dissolved in acetone (25 mL), and sodium azide (1.95 g, 30 mmol) was added. The mixture was refluxed at 60 °C and stirred for 11 h. After cooling to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to give 2,4,6-triazidopyrimidine-5-carboxynitrile (1.97 g), with a yield of 86.3%.

[0036] Example 3

[0037] The method for preparing the polyazido-based heterocyclic energetic compound of the present invention is as follows:

[0038] 2,4,6-trichloro-5-cyanopyrimidine (2.08 g, 10.0 mmol) was dissolved in acetone (25 mL), sodium azide (1.95 g, 30 mmol) was added, the mixture was refluxed at 65 °C and stirred for 12 h, cooled to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to give 2,4,6-triazidopyrimidine-5-carboxynitrile (1.91 g), with a yield of 83.7%.

[0039] Example 4

[0040] The method for preparing the polyazido-based heterocyclic energetic compound of the present invention is as follows:

[0041] 2,4,6-trichloro-5-cyanopyrimidine (2.08 g, 10.0 mmol) was dissolved in acetone (25 mL), sodium azide (1.95 g, 30 mmol) was added, the mixture was refluxed at 60 °C and stirred for 12 h, cooled to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to give 2,4,6-triazidopyrimidine-5-carboxynitrile (2.13 g), with a yield of 93.4%.

[0042] Comparative Example 1

[0043] Sodium azide (1.6 g, 24.4 mmol) was added to a 100 mL two-necked round-bottom flask, followed by 20 mL of deionized water. The flask was then placed in an ice-water bath. 2,4,6-Trichloro-5-cyanopyrimidine (1.12 g, 5.4 mmol) was added to the reaction mixture in portions. A large amount of white precipitate formed with each addition. After the addition was complete, stirring was continued for 4 hours. The solid in the reaction flask was filtered, washed with water, and dried at 60 °C to obtain a white powder. The reaction failure was confirmed by the peak values ​​in the nuclear magnetic resonance (NMR) spectrum.

[0044] Comparative Example 2

[0045] 2,4,6-trichloro-5-cyanopyrimidine (2.08 g, 10.0 mmol) was dissolved in a mixture of acetone and water (50 ml), and sodium azide (1.95 g, 30 mmol) was added. The mixture was stirred overnight at 50 °C and cooled to room temperature to obtain an oily liquid. The reaction failed.

[0046] The 2,4,6-triazidopyrimidine-5-carboxynitrile obtained in Examples 1-4 was dissolved in methanol and slowly evaporated at room temperature to obtain pale yellow blocky single crystals. Single-crystal X-ray diffraction tests were performed, and its crystal structure is as follows. Figure 1-3 As shown, their unit cell parameters are the same, as shown in Table 1 below.

[0047] Table 1. Crystal data for 2,4,6-triazidopyrimidine-5-formonitrile

[0048]

[0049] Structural characterization

[0050] The 2,4,6-triazidopyrimidine-5-carboxynitrile obtained in Example 1 was characterized, and the analytical results are shown in [Figure 1]. Figures 4-6 As shown.

[0051] Depend on Figure 4 The NMR spectrum can be obtained as follows: 13 C NMR (DMSO-d6): δ167.05, 162.49, 111.57, 80.83ppm.

[0052] Depend on Figure 5 From the infrared spectrum, we can obtain IR(ATR): 2366.22,2339.27,2234.44(-CN),2211.98,2156.44(-N3),2123.36,2092.18,1612.98,1558.71,1522.72,1418 .41,1365.52,1235.50,1205.07,1153.68,1133.54,1002.12,808.39,779.01,738.46,656.07,615.64,543.71cm -1 .

[0053] Elemental analysis C5N12 (228.07): Measured (calculated) C 26.13 (26.32), N 73.87 (73.68).

[0054] like Figure 6 The differential scanning calorimetry (DSC) curve shown indicates that the exothermic zone is 160–215 °C, and the decomposition temperature (Tonset) is 160 °C (heating rate 5 °C / min). -1 It exhibits a significant melting and endothermic process before thermal decomposition, and has the remarkable exothermic characteristics of energetic compounds.

[0055] Performance testing

[0056] 1. The nitrogen content of the 2,4,6-triazidopyrimidine-5-carboxynitrile obtained in Example 1 was calculated to be 73.87%.

[0057] 2. The density of the 2,4,6-triazidopyrimidine-5-carboxynitrile obtained in Example 1 was tested to be 1.606 g·cm³. -3 It exhibits excellent detonation performance, with a calculated detonation pressure of 23.6 GPa and a detonation velocity of 7197 m / s based on EXPLO5. -1 .

[0058] 3. Sensitivity Test

[0059] The testing method is as follows: both impact sensitivity and friction sensitivity are tested using the standard BAM method.

[0060] The 2,4,6-triazidopyrimidine-5-carboxynitrile obtained in Example 1 was tested and found to have an impact sensitivity of 5 J and a friction sensitivity of 120 N.

Claims

1. A polyazido-based heterocyclic energetic compound, characterized in that, Chemical formula C5N 12 Structural formula: ； The crystal parameters of the compound are: Crystal system: monoclinic; Point group: P21 / c; Cell parameters: a = 11.494 (3) Å, b = 10.725 (3) Å, c = 15.525 (4) Å, α = γ = 90°, β = 99.618 (6) °; Volume of the unit cell: 1887.0 (7) A3 3 ; Z = 8。 2. The polyazido-based heterocyclic energetic compound according to claim 1, characterized in that The crystal has one exothermic peak at 160-215 °C.

3. The polyazido-based heterocyclic energetic compound according to claim 1, characterized in that The EXPLO5 calculated detonation pressure of the compound is 23.6 GPa, and the detonation velocity is 7197 m-s -1 .

4. A process for the preparation of the polyazido-based heterocyclic energetic compound according to claim 1, characterized in that, The method comprises the following steps: 2,4,6-trichloro-5-cyanopyrimidine is reacted with sodium azide in a solvent of acetone, and the reaction temperature is 55-60 °C; The synthesis route is as follows: 。 5. Process for the preparation of a polyazido-based heterocyclic energetic compound according to claim 4, characterized in that, The molar ratio of 2,4,6-trichloro-5-cyanopyrimidine to sodium azide is 1:3-3.

5.

6. The process for the preparation of a polyazido-based heterocyclic energetic compound according to claim 4, characterized in that, The reaction time is 12-14 h.

7. Use of the multi-azido heterocyclic energetic compound according to any one of claims 1-3 as a green primary explosive.

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