Gem-dinitrobitetrazole and ammonium salt, preparation method and application thereof

Abstract

The invention relates to gem-dinitrobitetrazole and ammonium salt thereof, a preparation method and application, and belongs to the technical field of energetic materials. The molecular formula of the gem-dinitro bistetrazole is C4H2N12O8, and the molecular formula of the gem-dinitro bistetrazole diammonium salt is C4H8N14O8. Bitetrazole reacts with NaOH and bromoacetone to obtain isomers of three diacetone bitetrazole compounds, and gem-dinitrobitetrazole can be obtained by adopting three different nitration methods. And reacting the gem-dinitro bistetrazole with ammonia water to prepare the gem-dinitro bistetrazole diammonium salt. The density of the two is more than 1.85 g / cm < 3 >, the oxygen balance is close to 0, the detonation performance is good, the explosive does not contain halogen, has the characteristics of greenness and high energy, and is a good high explosive.

Description

Technical Field

[0001] The invention relates to gem-dinitrobistetrazole and its ammonium salt, a preparation method and application, and belongs to the technical field of energetic materials. Background Art

[0002] In recent years, due to the excellent detonation performance of high nitrogen compounds, their development has received widespread attention. High nitrogen compounds are increasingly becoming a new generation of energetic materials. This compound composed of a large number of N=N bonds or NN bonds decomposes into N2 molecules and releases a large amount of energy at the same time. Its energy storage and release law is also different from that of traditional CHON energetic materials. Theoretical calculations show that total nitrogen compounds have a higher formation enthalpy (8×10 3 ~2×10 4 kJ kg -1 ), the energy can reach 3 to 8 times of TNT equivalent, the formation enthalpy is high, and the detonation products are clean and pollution-free. However, high-nitrogen compounds often have low density, which seriously limits their detonation ability. How to improve the density of nitrogen-rich skeletons has become the focus of research. Summary of the invention

[0003] In view of this, the object of the present invention is to provide a gem-dinitrobistetrazole and its ammonium salt, a preparation method and application.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows.

[0005] A geminal dinitrobitriazole with the molecular formula C4H2N 12 O8, structural formula:

[0006]

[0007] A geminal dinitrobiquatrazolium diammonium salt, molecular formula C4H8N 14 O8, structural formula:

[0008]

[0009] A method for preparing gem-dinitrobistetrazole according to the present invention comprises the following steps:

[0010] (1) dissolving bitetrazole in water, adding NaOH and bromoacetone, reacting at 20-80° C. for 8-24 hours, filtering and collecting the solid to obtain a mixture of intermediate products;

[0011] (2) separating the mixture to obtain a first intermediate product, a second intermediate product, and a third intermediate product, respectively;

[0012] Among them, the structural formula of the first intermediate product is:

[0013] The structural formula of the second intermediate product is:

[0014] The structural formula of the third intermediate product is:

[0015] (3) adding the first intermediate product to the nitration system under stirring at -5 to 5°C, heating to 70±5°C within 20 to 30 minutes, then stopping the heating, cooling to 20 to 30°C, filtering, washing, and crystallizing to obtain gem-dinitrobiquatrazol; preferably, adding nitric acid with a mass fraction of 63% to 67% to sulfuric acid with a mass fraction of 98%, adding trifluoroacetic acid, adding the first intermediate product in batches under stirring at -5 to 5°C, heating to 70±5°C within 20 to 30 minutes, then stopping the reaction, cooling to 20 to 30°C, filtering, washing, and crystallizing to obtain gem-dinitrobiquatrazol; more preferably, the volume ratio of nitric acid, sulfuric acid and trifluoroacetic acid is 1:0.5 to 1.5:1; and the dosage ratio of the first intermediate product to nitric acid is 1g:3 to 6ml.

[0016] The second intermediate product is added to the nitrating agent under stirring at a temperature below -10°C, the temperature is raised to 0-5°C, the reaction is stirred for more than 24 hours, the product is filtered, washed, and crystallized to obtain gem-dinitrobiquatrazol; preferably, nitric acid with a mass fraction of 63% to 67% is added to sulfuric acid with a mass fraction of 98%, the second intermediate product is added in batches under stirring at a temperature below -10°C, the temperature is raised to 0-5°C, the reaction is stirred for 24-48 hours, the product is filtered, washed, and crystallized to obtain gem-dinitrobiquatrazol; more preferably, the volume ratio of nitric acid to sulfuric acid is 1:1.5-2.5; and the dosage ratio of the second intermediate product to nitric acid is 1g:3-6ml.

[0017] The third intermediate product is added to the nitrating agent under stirring at -5 to 5°C, reacted at 20 to 30°C for more than 4 hours, filtered, washed, and crystallized to obtain gem-dinitrobiquatrazol. Preferably, nitric acid with a mass fraction of 63% to 67% is added to sulfuric acid with a mass fraction of 98%, the third intermediate product is added in batches under stirring at -5 to 5°C, reacted at 20 to 30°C for more than 4 hours, filtered, washed, and crystallized to obtain gem-dinitrobiquatrazol; more preferably, the volume ratio of nitric acid to sulfuric acid is 1:1 to 1.2; the dosage ratio of the third intermediate product to nitric acid is 1g:3 to 6ml.

[0018] Preferably, in step (1), the tetrazole is prepared by the following method: dissolving tetrazole diammonium salt in water, adding sulfuric acid for acidification; then extracting with ethyl acetate, and drying by spin drying to obtain tetrazole.

[0019] Preferably, in step (1), the molar ratio of the tetrazole to NaOH is 1:2-3; the molar ratio of the tetrazole to bromoacetone is 1:2-3.

[0020] Preferably, in step (2), the mixture is slurried in acetonitrile, filtered and separated, and the solid is collected to obtain a first intermediate product; the filtrate is collected, evaporated and recrystallized to obtain a second intermediate product; and the residual liquid after recrystallization is spin-dried to obtain a third intermediate product.

[0021] Preferably, during slurrying, the ratio of the mixture to acetonitrile is 1-2 g:10-15 ml.

[0022] A method for preparing the gem-dinitrobistetrazole diammonium salt of the present invention comprises the following steps:

[0023] The gem-dinitrobistetrazole is dissolved in methanol, and aqueous ammonia is added dropwise until precipitation is complete. The precipitate is collected by filtration to obtain gem-dinitrobistetrazole diammonium salt.

[0024] Preferably, the molar ratio of ammonium ions to gem-dinitrobistetrazole in the ammonia water is 2 to 3.5:1.

[0025] An application of the gem-dinitrobitetrazole of the present invention, wherein the gem-dinitrobitetrazole is used as a high explosive.

[0026] An application of the gem-dinitrobi-tetrazolyl diammonium salt of the present invention, wherein the gem-dinitrobi-tetrazolyl diammonium salt is used as a high explosive.

[0027] Beneficial Effects

[0028] The present invention provides a geminal dinitro tetrazolyl and its ammonium salt, which realizes the introduction of geminal dinitro into the nitrogen-rich skeleton tetrazolyl, and successfully improves the density and detonation performance of the nitrogen-rich skeleton. The density of both is 1.85g / cm 3 Above, the oxygen balance is close to 0 oxygen balance, the detonation performance is good, it does not contain halogen, has the characteristics of greenness and high energy, and is a good high explosive.

[0029] The invention provides a method for preparing gem-dinitrobitetrazole and its ammonium salt. The bitetrazole reacts with NaOH and bromoacetone to obtain three isomers of diacetonylbitetrazole compounds. The gem-dinitrobitetrazole can be obtained by adopting three different nitration methods. The first intermediate product and the second intermediate product are nitrated to a stable meta-substituted gem-dinitrobitetrazole after rearrangement, and the yield of the gem-dinitrobitetrazole can reach more than 80%. The gem-dinitrobitetrazole reacts with ammonia water to prepare the gem-dinitrobitetrazole diammonium salt. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the single crystal structure diagram of the first intermediate product in Example 1 by X-ray diffraction.

[0031] Figure 2 This is the single crystal structure diagram of the third intermediate product in Example 1 by X-ray diffraction.

[0032] Figure 3 This is the single crystal structure diagram of gem-dinitrobitetrazole in Example 1 by X-ray diffraction.

[0033] Figure 4 This is the single crystal structure diagram of the gem-dinitrobistetrazole diammonium salt in Example 2 by X-ray diffraction. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below in conjunction with specific embodiments.

[0035] In the following examples or comparative examples:

[0036] (1) Single crystal X-ray diffraction: The instrument is Bruker D2 Advance with a Cu Karadiation, and the test temperature is 170K.

[0037] (2) Nuclear magnetic resonance testing: The instrument used was a Bruker Ascend 400 MHz nuclear magnetic spectrometer.

[0038] (3) Thermal decomposition temperature test: The instrument is TA-DSC Q2000 differential scanning calorimeter.

[0039] (4) Impact sensitivity test: The instrument is a BAM drop weight sensitivity meter.

[0040] (5) Friction sensitivity test: The instrument is FSKM-10BAM friction sensitivity meter.

[0041] (6) Density, oxygen balance, oxygen content and nitrogen and oxygen content are calculated values.

[0042] Example 1

[0043] 5,5'-bis-tetrazole (4.14g 30mmol) is dissolved in the water containing 2.2eq NaOH. Subsequently, bromoacetone (4.52g 33mmol) dissolved in 15mL acetone is added to the obtained solution at room temperature. The reaction mixture is then heated to 70 ℃ (or at 20 ℃) ​​and stirred for 16 hours. Remove the solvent under reduced pressure to obtain an intermediate product mixture 5.72g (productivity 76.24%).

[0044] 5.72 g of the intermediate product mixture was added to 58 ml of acetonitrile, stirred for 15 min, filtered, and dried to obtain 1.27 g of the first intermediate product. The filtrate was naturally evaporated to 10 ml remaining, and colorless crystals were precipitated. The second intermediate product was filtered and dried to obtain 3.44 g of the second intermediate product. The remaining filtrate was spin-dried to obtain 1.01 g of the third intermediate product as a white solid. The structural formula of the first intermediate product is: The results of H-NMR and C-NMR are: 1H NMR (deuterated dimethyl sulfoxide): δ=2.34 (S, 6H) δ=6.14 (S, 4H). 13 C NMR (deuterated dimethyl sulfoxide): δ = 199.58, 143.42, 58.67, 27.59. The single crystal structure is shown in Figure 1 shown.

[0045] The structural formula of the second intermediate product is: The results of H-NMR and C-NMR are: 1 HNMR (deuterated acetone): δ = 2.41 (d, 6H), δ = 6.05, 6.02 (d, 4H). 13 C NMR (deuterated acetonitrile): δ = 199.42, 198.81, 154.01, 146.27, 62.35, 58.43, 27.19, 27.09.

[0046] The structural formula of the third intermediate product is: The results of H-NMR and C-NMR are: 1 H NMR (deuterated dimethyl sulfoxide): δ=2.39(S,6H)δ=6.04(S,4H). 13 C NMR (deuterated dimethyl sulfoxide): δ = 199.58, 143.42, 58.67, 27.59. The single crystal structure is shown in Figure 2 shown.

[0047] HNO3 (67%, 5mL) was added to H2SO4 (98%, 5ml), followed by 5ml of trifluoroacetic acid, stirred at 0°C, and then the first intermediate product (1.0g) was added to the mixed acid in batches, heated to 70°C in 30 minutes, the reaction was immediately stopped, cooled to room temperature, filtered, washed with CF3COOH (10mL), and crystallized from dichloromethane to obtain geminal dinitrotetrazole with a yield of 84% (1.1g).

[0048] HNO3 (67%, 5 mL) was added to H2SO4 (98%, 10 ml), stirred at -10°C, and then the second intermediate product (1.0 g) was added to the mixed acid in batches. After 0.5 hours, the reaction mixture was heated to 0°C and stirred for 24 hours, then the product was isolated by filtration, washed with CF3COOH (10 mL), and crystallized from dichloromethane to obtain a 55% yield (720 mg) of gem-dinitrobistetrazole.

[0049] HNO3 (67%, 5 mL) was added to H2SO4 (98%, 5 ml), stirred at 0°C, and then the third intermediate product (1.0 g) was added to the mixed acid in batches, warmed to room temperature and reacted for 4 hours. The product was then filtered and separated, washed with CF3COOH (10 mL), and crystallized from dichloromethane to obtain geminal dinitrotetrazole with a yield of 47% (615 mg).

[0050] The reaction route is as follows:

[0051]

[0052] The results of H NMR and C NMR of the geminal dinitrobitetrazole are: 1 H NMR (deuterated chloroform): δ=8.33 (S, 1H). 13 C NMR (deuterated acetonitrile): δ = 157.21, 105.78. The single crystal structure is shown in Figure 3 shown.

[0053] The thermal decomposition temperature, density, impact sensitivity, friction sensitivity, and oxygen balance results of the gem-dinitrobistetrazole are shown in Table 1. Calculations show that the formation enthalpy of the compound is 597.1 KJ / mol, the detonation velocity is 9305 m / s, and the detonation pressure is 38.0 GPa.

[0054] In conclusion, gem-dinitrobitetrazole can be used as a high explosive due to its excellent detonation velocity and detonation pressure.

[0055] Example 2

[0056] 1 g of gem-dinitrobitetrazole prepared in Example 1 was dissolved in 2 ml of methanol, and 0.5 ml of 28% ammonia water was added dropwise to precipitate solid, which was filtered and naturally air-dried to obtain 0.8 g of yellow-white solid gem-dinitrobitetrazole diammonium salt.

[0057] The reaction route is as follows:

[0058]

[0059] The NMR carbon spectrum results of the gem-dinitrobistetrazole diammonium salt are: 13 C NMR (deuterated methanol): δ = 155.73, 131.03. The single crystal structure is shown in Figure 4 shown.

[0060] The thermal decomposition temperature, density, impact sensitivity, friction sensitivity and oxygen balance results of the gem-dinitrobistetrazole diammonium salt are shown in Table 1.

[0061] Table 1

[0062]

[0063] Comparative Example 1

[0064] At room temperature, tetrazolyl was dissolved in water, 2.2 molar equivalents of sodium hydroxide were added, and chloroacetone was used instead of bromoacetone at room temperature. No solid was precipitated, the reaction did not occur, and no intermediate product could be obtained.

[0065] Comparative Example 2

[0066] At room temperature, a mixed acid of 67% nitric acid: 98% sulfuric acid = 1:1 (volume ratio) was prepared, and then the second intermediate product was added and reacted at room temperature. Finally, no solid precipitation was observed, and the product did not rearrange but decomposed.

[0067] Comparative Example 3

[0068] At 0°C, a mixed acid of 67% nitric acid: 98% sulfuric acid: trifluoroacetic acid = 1:1:1 (volume ratio) was prepared and the second intermediate product was added. The temperature was raised to 70°C within 30 minutes and then the reaction was stopped and the temperature was lowered. Finally, no solid precipitation was observed and the product did not rearrange but decomposed.

[0069] Comparative Example 4

[0070] At room temperature, after preparing a mixed acid of 67% nitric acid: 98% sulfuric acid = 1:1 (volume ratio), the first intermediate product was added and reacted at room temperature. Finally, no solid precipitation was observed, and the product did not rearrange but decomposed.

[0071] At -10°C, a mixed acid of 67% nitric acid: 98% sulfuric acid = 1:2 was prepared, and the first intermediate product was added and reacted at 0°C. Finally, no solid precipitation was observed, and the product did not rearrange but decomposed.

[0072] Comparative Example 5

[0073] When the nitration temperature of the first intermediate product was increased to 80°C, the product decomposed; when the nitration temperature of the compound was lowered to 50°C, the product did not completely rearrange and partially decomposed, and no pure product was obtained.

[0074] Comparative Example 6

[0075] In both the examples and comparative examples, 100% nitric acid was used instead of 67% nitric acid for adding materials and reacting at 0° C. Finally, no solid precipitation was observed, and the pure compound could not be obtained.

[0076] In summary, the invention includes but is not limited to the above embodiments. Any equivalent substitution or partial improvement made under the spirit and principle of the invention shall be deemed to be within the protection scope of the invention.

Claims

1. A geminal dinitrobiquatrazol, characterized in that: The molecular formula is C4H2N 12 O8, structural formula:

2. A gem-dinitrobistetrazole diammonium salt as claimed in claim 1, characterized in that: The molecular formula is C4H8N 14 O8, structural formula:

3. A method for preparing gem-dinitrobitetrazole as claimed in claim 1, characterized in that: The method steps include: (1) dissolving bitetrazole in water, adding NaOH and bromoacetone, reacting at 20-80° C. for 8-24 hours, filtering and collecting the solid to obtain a mixture of intermediate products; (2) separating the mixture to obtain a first intermediate product, a second intermediate product, and a third intermediate product, respectively; Among them, the structural formula of the first intermediate product is: The structural formula of the second intermediate product is: The structural formula of the third intermediate product is: (3) adding nitric acid with a mass fraction of 63% to 67% to sulfuric acid with a mass fraction of 98%, adding trifluoroacetic acid, adding the first intermediate product in batches under stirring at -5 to 5°C, heating to 70±5°C within 20 to 30 minutes, then stopping the reaction, cooling to 20 to 30°C, filtering, washing, and crystallizing to obtain gem-dinitrobistetrazole; Add nitric acid with a mass fraction of 63% to 67% to sulfuric acid with a mass fraction of 98%, add the second intermediate product in batches under stirring at a temperature below -10°C, raise the temperature to 0 to 5°C, stir and react for 24 to 48 hours, filter, wash, and crystallize to obtain gem-dinitrobistetrazole; Nitric acid with a mass fraction of 63% to 67% is added to sulfuric acid with a mass fraction of 98%, and the third intermediate product is added in batches under stirring at -5 to 5°C, reacted at 20 to 30°C for more than 4 hours, filtered, washed, and crystallized to obtain gem-dinitrobistetrazole.

4. A method for preparing a gem-dinitrobistetrazole as claimed in claim 3, characterized in that: In step (1), the tetrazole is prepared by the following method: dissolving tetrazole diammonium salt in water, adding sulfuric acid for acidification; then extracting with ethyl acetate, and spinning to dryness to obtain tetrazole; preferably, the molar ratio of the tetrazole to NaOH is 1:2-3; the molar ratio of the tetrazole to bromoacetone is 1:2-3.

5. A method for preparing gem-dinitrobistetrazole as claimed in claim 3, characterized in that: In step (2), the mixture is slurried in acetonitrile, filtered and separated, and the solid is collected to obtain a first intermediate product; The filtrate is collected, evaporated and recrystallized to obtain the second intermediate product; The residual liquid after recrystallization is spin-dried to obtain the third intermediate product.

6. A method for preparing gem-dinitrobistetrazole as claimed in claim 5, characterized in that: During slurrying, the ratio of the mixture to acetonitrile is 1-2 g:10-15 ml.

7. A method for preparing gem-dinitrobistetrazole as claimed in claim 3, characterized in that: In step (3), when the first intermediate product is reacted, the volume ratio of nitric acid, sulfuric acid and trifluoroacetic acid is 1:0.5 to 1.5:1; The dosage ratio of the first intermediate product to nitric acid is 1g:3-6ml; When the second intermediate product is reacted: the volume ratio of nitric acid to sulfuric acid is 1:1.5-2.5; the dosage ratio of the second intermediate product to nitric acid is 1g:3-6ml; When the third intermediate product is reacted, the volume ratio of nitric acid to sulfuric acid is 1:1-1.2; the dosage ratio of the third intermediate product to nitric acid is 1g:3-6ml.

8. A method for preparing the gem-dinitrobistetrazole diammonium salt as claimed in claim 2, characterized in that: The method steps include: The gem-dinitrobitetrazole prepared by the method according to any one of claims 3 to 7 is dissolved in methanol, ammonia water is added dropwise until precipitation is complete, and the precipitate is collected by filtration to obtain gem-dinitrobitetrazole diammonium salt; preferably, the molar ratio of ammonium ions to gem-dinitrobitetrazole in the ammonia water is 2 to 3.5:

1.

9. A use of the gem-dinitrobistetrazole as claimed in claim 1, characterized in that: The gem-dinitrobitetrazole is used as a high explosive.

10. An application of the gem-dinitrobistetrazole diammonium salt as claimed in claim 2, characterized in that: The gem-dinitrobistetrazole diammonium salt is used as a high explosive.

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