Multi-azido heterocyclic energetic compound as well as preparation method and application thereof

Abstract

The invention discloses a multi-azido heterocyclic energetic compound with a structural formula I, the chemical formula of the multi-azido heterocyclic energetic compound is C5N12, and the multi-azido heterocyclic energetic compound is prepared by reacting 2, 4, 6-trichloro-5-cyanopyrimidine with sodium azide in a solvent. The multi-azido heterocyclic energetic compound disclosed by the invention has good thermal stability and detonation performance, and the detonation pressure is 23.6 GPa and the detonation velocity is 7197m. S <-1 > calculated by EXPLO5. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to an energetic compound, in particular to a polyazido heterocyclic energetic compound and a preparation method and application thereof. Background Art

[0002] Explosives are a type of explosive that can be detonated under weak stimulation (such as impact, friction, vibration, heating and static electricity). They are the most sensitive and first-acting agents in pyrotechnics. They directly control the sensitivity, intensity and effect of pyrotechnics, and their position in pyrotechnics cannot be replaced by other energetic materials. Traditional lead-sensitive compounds such as lead styphnate (LTNR) and lead azide (LA) are the key components of the most widely used pyrotechnics. Toxic additives such as antimony sulfide and barium nitrate are often used. These pyrotechnics are too sensitive and contain heavy metal substances, which are harmful to the environment and affect human health. With the development of new pyrotechnic detonation technology, traditional pyrotechnics can no longer meet the requirements of advanced pyrotechnics. Therefore, it is urgent to carry out research on green pyrotechnics that do not contain heavy metals such as lead and mercury, have certain stability and good explosive performance. Summary of the invention

[0003] Purpose of the invention: The first purpose of the present invention is to provide a polyazido-heterocyclic energetic compound with good detonation performance; the second purpose of the present invention is to provide a method for preparing the polyazido-heterocyclic energetic compound; the third purpose of the present invention is to provide the application of the polyazido-heterocyclic energetic compound as a green explosive.

[0004] Technical solution: The polyazido heterocyclic energetic compound of the present invention has the chemical formula C 5 N 12 , the structural formula is:

[0005]

[0006] The crystal parameters of the compound are:

[0007] Crystal system: monoclinic;

[0008] Point group: P2 1 / c;

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

[0010] Unit cell volume:

[0011] Z=8.

[0012] The crystal has an exothermic peak at 160-215°C. The decomposition temperature Tonset is 168°C (heating rate 5°C·min-1 ), there is an obvious melting endothermic process before thermal decomposition, and it has significant exothermic characteristics of energetic compounds.

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

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

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

[0016] The method for preparing the polyazido heterocyclic energetic compound of the present invention comprises the following steps: reacting 2,4,6-trichloro-5-cyanopyrimidine with sodium azide in a solvent, and the synthesis 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 the 2,4,6-trichloro-5-cyanopyrimidine to sodium azide is 1:3 to 3.5.

[0021] The polyazido heterocyclic energetic compound of the present invention is used as a green explosive.

[0022] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The polyazido 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 heterocyclic energetic compound is environmentally friendly and can be used as a promising green detonator. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

[0027] Figure 5 This is the infrared spectrum of 2,4,6-triazidopyrimidine-5-carbonitrile prepared in Example 1 of the present invention;

[0028] Figure 6 The differential scanning calorimetry (heating rate 5°C·min) of 2,4,6-triazidopyrimidine-5-carbonitrile prepared in Example 1 of the present invention -1 ). DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described below in conjunction with embodiments.

[0030] Example 1

[0031] The method for preparing the polyazido 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), sodium azide (1.95 g, 30 mmol) was added, and the mixture was refluxed at 55°C with stirring for 10 h. The mixture was cooled to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to obtain 2,4,6-triazidopyrimidine-5-carbonitrile (1.89 g) with a yield of 82.8%.

[0033] Example 2

[0034] The method for preparing the polyazido 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), sodium azide (1.95 g, 30 mmol) was added, refluxed and stirred at 60°C for 11 h, cooled to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to obtain 2,4,6-triazidopyrimidine-5-carbonitrile (1.97 g) with a yield of 86.3%.

[0036] Example 3

[0037] The method for preparing the polyazido 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, refluxed at 65°C with stirring for 12 h, cooled to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to obtain 2,4,6-triazidopyrimidine-5-carbonitrile (1.91 g) with a yield of 83.7%.

[0039] Example 4

[0040] The method for preparing the polyazido 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, refluxed at 60°C with stirring for 12 h, cooled to room temperature, the precipitate was filtered off, and the filtrate was concentrated under reduced pressure to obtain 2,4,6-triazidopyrimidine-5-carbonitrile (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, deionized water (20 mL) was added, and the reaction flask was placed in an ice-water bath. Then 2,4,6-trichloro-5-cyanopyrimidine (1.12 g, 5.4 mmol) was added to the reaction in portions. A large amount of white precipitate was generated as the reactants were added. After the addition was completed, stirring was continued for 4 h. The solid in the reaction flask was filtered, washed with water, and dried at 60 ° C to obtain a white powder solid. The peak of the nuclear magnetic resonance spectrum confirmed the failure of the reaction.

[0044] Comparative Example 2

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

[0046] The 2,4,6-triazidopyrimidine-5-carbonitrile obtained in Example 1-4 was dissolved in methanol and slowly evaporated at room temperature to obtain a pale yellow block single crystal. The single crystal X-ray diffraction test was performed, and the crystal structure was as follows: Figure 1-3 As shown, the unit cell parameters are the same, as shown in Table 1 below.

[0047] Table 1 Crystal data of 2,4,6-triazidopyrimidine-5-carbonitrile

[0048]

[0049] Structural characterization

[0050] The 2,4,6-triazidopyrimidine-5-carbonitrile obtained in Example 1 was characterized, and the analysis results are shown in Figures 4 to 6 shown.

[0051] Depend on Figure 4 NMR spectra are available. 13 C NMR (DMSO-d 6 ): δ167.05, 162.49, 111.57, 80.83ppm.

[0052] Depend on Figure 5 Infrared spectrum is available, IR (ATR): 2366.22,2339.27,2234.44(-CN),2211.98,2156.44(-N 3 ),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): Found (calculated) C 26.13 (26.32), N 73.87 (73.68).

[0054] like Figure 6 The differential scanning calorimeter shown in the figure is as follows: DSC: the exothermic section is 160-215°C, the decomposition temperature Tonset is 160°C (heating rate 5°C·min -1 ), there is an obvious melting endothermic process before thermal decomposition, and it has significant exothermic characteristics of energetic compounds.

[0055] Performance Testing

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

[0057] 2. The density of 2,4,6-triazidopyrimidine-5-carbonitrile obtained in Example 1 was tested to be 1.606 g·cm -3 , with good detonation performance, EXPLO5 calculated detonation pressure is 23.6GPa, detonation velocity is 7197m·s -1 .

[0058] 3. Sensitivity test

[0059] The test method is: impact sensitivity and friction sensitivity both adopt the standard BAM method.

[0060] The 2,4,6-triazidopyrimidine-5-carbonitrile 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 heterocyclic energetic compound, characterized in that: The chemical formula is C5N 12 , the structural formula is:

2. The polyazido heterocyclic energetic compound according to claim 1, characterized in that: The crystal parameters of the compound are: Crystal system: monoclinic; Point group: P21 / c; Unit cell parameters: α=γ=90°, β=99.618(6)°; Unit cell volume: Z＝8。 3. The polyazido heterocyclic energetic compound according to claim 2, characterized in that: The crystal has an exothermic peak at 160-215°C.

4. The polyazido heterocyclic energetic compound according to claim 1, characterized in that: The compound's explosion pressure calculated by EXPLO5 is 23.6 GPa, and its explosion velocity is 7197 m·s -1 .

5. A method for preparing the polyazido heterocyclic energetic compound according to claim 1, characterized in that: The method comprises the following steps: reacting 2,4,6-trichloro-5-cyanopyrimidine with sodium azide in a solvent, and the synthesis route is as follows:

6. The method for preparing the polyazido heterocyclic energetic compound according to claim 5, characterized in that: The reaction temperature is 55-60°C.

7. The method for preparing the polyazido heterocyclic energetic compound according to claim 5, characterized in that: The molar ratio of the 2,4,6-trichloro-5-cyanopyrimidine to sodium azide is 1:3 to 3.

5.

8. The method for preparing the polyazido heterocyclic energetic compound according to claim 6, characterized in that: The reaction time is 12 to 14 hours.

9. The method for preparing the polyazido heterocyclic energetic compound according to claim 5, characterized in that: The solvent for the reaction is acetone.

10. Use of the polyazido heterocyclic energetic compound according to any one of claims 1 to 4 as a green explosive.

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