6 / 5 / 6-type 1,2,3-triazine n-oxide ternary fused ring energetic compounds and methods of making the same

Abstract

The application discloses a 6 / 5 / 6 type 1,2,3-triazine N The application discloses an oxide ternary fused ring energetic compound and a preparation method thereof, and the preparation method comprises the following steps: taking 3,5-diamino-4-cyanopyrazole as raw material, and performing ring closing reaction under the action of acid to obtain an intermediate product; the intermediate product is reacted with a hydroxylamine solution to prepare an intermediate product with an ortho amino-hydroxylamine group, and the target compound is further prepared under the action of a diazotization reagent. The target compound has the characteristics of high energy, low sensitivity, good thermal stability and the like, and is an energetic material with potential application value.

Description

Technical Field

[0001] The present invention belongs to the field of energetic materials, and in particular relates to an energetic organic compound and a preparation method thereof. Background Art

[0002] The design and synthesis of energetic compounds with both high energy levels and excellent safety performance has long been a goal pursued by researchers in energetic materials. Nitrogen-containing fused ring compounds offer advantages such as high formation enthalpy, good molecular stability, and the decomposition product of nitrogen, a green and non-polluting gas. Therefore, the design and synthesis of novel nitrogen-rich fused ring energetic compounds with excellent performance have attracted widespread attention.

[0003] Currently, the most studied nitrogen-rich fused-ring energetic compounds focus primarily on binary fused-ring compounds (e.g., 5 / 5 and 5 / 6 types). Studies on ternary fused-ring energetic frameworks are limited, primarily focusing on 5 / 6 / 5 type compounds. These frameworks suffer from a single type of framework and limited modification sites, which restricts further exploration and application of this class of compounds. Therefore, designing a novel fused-ring energetic framework, further modifying it to synthesize high-performance energetic compounds, and then applying it to production is a scientific challenge that urgently needs to be addressed. Summary of the Invention

[0004] The present invention aims to provide an energetic compound 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide and a preparation method thereof.

[0005] An energetic compound I, named 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide, has the structural formula:

[0006]

[0007] An energetic compound II, named 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide, has the structural formula:

[0008]

[0009] The present invention also provides a method for synthesizing energetic compound I, comprising:

[0010] (1) reacting 3,5-diamino-4-cyanopyrazole (1) with malononitrile under the action of an acid to prepare a compound 2,5,7-triamino-3-cyanopyrazolo[1,5-a]pyrimidine (2);

[0011]

[0012] (2) a step of reacting 2,5,7-triamino-3-cyanopyrazolo[1,5-a]pyrimidine (2) in a hydroxylamine solution to prepare compound (Z)-2,5,7-triamino-3-aminoximopyrazolo[1,5-a]pyrimidine (3);

[0013]

[0014] (3) reacting (Z)-2,5,7-triamino-3-aminoximinopyrazolo[1,5-a]pyrimidine (3) with a diazotizing agent to prepare the target product 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I);

[0015]

[0016] Preferably, in step (1), the acid is any one of formic acid, acetic acid and hydrochloric acid.

[0017] Preferably, in step (1), the reaction is carried out in the presence of an organic solvent, which is any one of acetonitrile, methanol and ethanol.

[0018] Preferably, in step (1), the reaction temperature is 40-80° C. and the reaction time is 60-180 minutes.

[0019] Preferably, in step (2), the reaction is carried out in the presence of an organic solvent, which is any one of methanol, ethanol and acetonitrile.

[0020] Preferably, in step (2), the mass fraction of the hydroxylamine solution is 30% to 50%.

[0021] Preferably, in step (2), the reaction temperature is 60-80° C., and the reaction time is 3-12 hours.

[0022] Preferably, in step (3), the diazotization reagent is any one of tert-butyl nitrite, nitrosylsulfuric acid and sodium nitrite.

[0023] Preferably, in step (3), the reaction is carried out in the presence of an acid, which is any one of sulfuric acid, hydrochloric acid and acetic acid.

[0024] Preferably, in step (3), the reaction temperature is -5 to 5°C, and the reaction time is 30 to 180 minutes.

[0025] The present invention also provides a method for synthesizing energetic compound II, comprising:

[0026] (1) reacting 3,5-diamino-4-cyanopyrazole (1) with 3,3-diethoxypropionitrile under the action of an acid to prepare a compound 2,7-diamino-3-cyanopyrazolo[1,5-a]pyrimidine (2a);

[0027]

[0028] (2) a step of reacting 2,7-diamino-3-cyanopyrazolo[1,5-a]pyrimidine (2a) in a hydroxylamine solution to prepare compound (Z)-2,7-diamino-3-aminoximopyrazolo[1,5-a]pyrimidine (3a);

[0029]

[0030] (3) a step of reacting (Z)-2,7-diamino-3-aminoximinopyrazolo[1,5-a]pyrimidine (3a) with a diazotizing agent to prepare 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (II);

[0031]

[0032] Preferably, in step (1), the acid is any one of formic acid, acetic acid and hydrochloric acid.

[0033] Preferably, in step (1), the reaction is carried out in the presence of an organic solvent, which is any one of acetonitrile, methanol and ethanol.

[0034] Preferably, in step (1), the reaction temperature is 40-80° C. and the reaction time is 60-180 minutes.

[0035] Preferably, in step (2), the reaction is carried out in the presence of an organic solvent, which is any one of methanol, ethanol and acetonitrile.

[0036] Preferably, in step (2), the mass fraction of the hydroxylamine solution is 30% to 50%.

[0037] Preferably, in step (2), the reaction temperature is 60-80° C., and the reaction time is 3-12 hours.

[0038] Preferably, in step (3), the diazotization reagent is any one of tert-butyl nitrite, nitrosylsulfuric acid and sodium nitrite.

[0039] Preferably, in step (3), the reaction is carried out in the presence of an acid, which is any one of sulfuric acid, hydrochloric acid and acetic acid.

[0040] Preferably, in step (3), the reaction temperature is -5 to 5°C, and the reaction time is 30 to 180 minutes.

[0041] The present invention also provides the use of the energetic compound I as a heat-resistant explosive.

[0042] The present invention also provides the use of the energetic compound II as a heat-resistant explosive.

[0043] Compared with the prior art, the present invention has the following advantages: (1) The energetic compound 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide is a novel 6 / 5 / 6-type ternary fused ring energetic compound with more modification sites and functional derivatization characteristics, and has good thermal stability (thermal decomposition temperature: 182°C), making it an energetic material with potential application value. (2) The raw materials for preparing the compound are readily available, and the synthetic route is simple and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a real sample image of 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I).

[0045] Figure 2 This is the H NMR spectrum of 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I).

[0046] Figure 3 This is the C NMR spectrum of 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I).

[0047] Figure 4 This is the DSC chart of 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I).

[0048] Figure 5 This is the H NMR spectrum of 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (II).

[0049] Figure 6 This is the C NMR spectrum of 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (II).

[0050] Figure 7This is the DSC chart of 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (II). DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0052] The specific steps are as follows:

[0053] (1) Synthesis of 2,5,7-triamino-3-cyanopyrazolo[1,5-a]pyrimidine (2)

[0054] 3,5-Diamino-4-cyanopyrazole (1) is dispersed in an organic solvent and stirred at 40-80°C. Malononitrile and acid are sequentially added to the solution and stirred for 60-180 minutes. The solution is then filtered, washed, and dried to obtain 2,5,7-triamino-3-cyanopyrazolo[1,5-a]pyrimidine (referred to as compound 2). The organic solvent used is any one of acetonitrile, methanol, and ethanol, and the acid used is any one of formic acid, acetic acid, and hydrochloric acid.

[0055] (2) Synthesis of (Z)-2,5,7-triamino-3-aminoxime-pyrazolo[1,5-a]pyrimidine (3)

[0056] Compound 2 is dispersed in an organic solvent, and then a hydroxylamine solution is added dropwise, wherein the mass fraction of the hydroxylamine solution used is 30% to 50%, and the organic solvent is any one of methanol, ethanol and acetonitrile; then the temperature of the reaction system is raised to 60 to 80°C, and the reaction time is 3 to 12 hours. The reaction system is then cooled, filtered, washed, and dried to obtain a solid product (Z)-2,5,7-triamino-3-aminoximopyrazolo[1,5-a]pyrimidine (referred to as compound 3).

[0057] (3) Synthesis of 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I)

[0058] Compound 3 is dissolved in an acid, wherein the acid used is any one of concentrated sulfuric acid, concentrated hydrochloric acid, and acetic acid; then, a sufficient amount of a diazotization reagent is added to the solution in batches, wherein the diazotization reagent used is any one of tert-butyl nitrite, nitrosylsulfuric acid, and sodium nitrite. After the addition, the system is heated to -5 to 5°C and reacted for 30 to 180 minutes. The reaction system is then cooled and poured into ice water, filtered, washed, and dried to obtain the target product 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (referred to as target product I).

[0059] The present invention has a second synthetic route:

[0060]

[0061] The specific steps are as follows:

[0062] (1) Synthesis of 2,7-diamino-3-cyanopyrazolo[1,5-a]pyrimidine (2a)

[0063] 3,5-Diamino-4-cyanopyrazole (1) is dispersed in an organic solvent and stirred at 40-80°C. 3,3-diethoxypropionitrile and an acid are sequentially added to the solution and stirred for 60-180 minutes. The solution is then filtered, washed, and dried to obtain 2,7-diamino-3-cyanopyrazolo[1,5-a]pyrimidine (referred to as compound 2a). The organic solvent used is any one of acetonitrile, methanol, and ethanol, and the acid used is any one of formic acid, acetic acid, and hydrochloric acid.

[0064] (2) Synthesis of (Z)-2,7-diamino-3-aminoxime pyrazolo[1,5-a]pyrimidine (3a)

[0065] Compound 2a is dispersed in an organic solvent, and a hydroxylamine solution is added dropwise, wherein the mass fraction of the hydroxylamine solution used is 30% to 50%, and the organic solvent is any one of methanol, ethanol, and acetonitrile; then the temperature of the reaction system is raised to 60 to 80°C, and the reaction time is 3 to 12 hours. The reaction system is then cooled, filtered, washed, and dried to obtain a solid product (Z)-2,7-diamino-3-aminoximopyrazolo[1,5-a]pyrimidine (referred to as compound 3a).

[0066] (3) Synthesis of 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (II)

[0067] Compound 3a is dissolved in an acid, which is any one of concentrated sulfuric acid, concentrated hydrochloric acid, and acetic acid. A sufficient amount of a diazotization reagent, which is any one of tert-butyl nitrite, nitrosylsulfuric acid, and sodium nitrite, is then added to the solution in batches. After the addition, the system is heated to -5 to 5°C and reacted for 30 to 180 minutes. The reaction system is then cooled and poured into ice water, filtered, washed, and dried to obtain the target product 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (referred to as target product II).

[0068] Example 1

[0069] 1.23 g (10.0 mmol) of 3,5-diamino-4-cyanopyrazole (prepared with reference to WJ Middleton, VA Engelhardt, J.Am.Chem.Soc.1958,80,2829–2832) was dispersed in 20 mL of acetonitrile and stirred. Malononitrile (0.66 g, 10.0 mmol) and formic acid (1 mL) were then added to the solution in sequence. After the addition was completed, the mixture was stirred at 80°C for 3 hours, then cooled, filtered, washed, and dried to obtain compound 2 (yield: 70%, 1.32 g).

[0070] Compound 2 (1.88 g, 10.0 mmol) was dispersed in 20 mL of methanol solution, and 30% hydroxylamine solution (1.65 g, 15.0 mmol) was added dropwise to the solution. The temperature was raised to 60 ° C and heated for 3 hours. After the heating was completed, the reaction system was cooled, filtered and dried to obtain compound 3 (yield: 85%, 1.89 g). Compound 3 (0.45 g, 2.0 mmol) was then added to 10 mL of concentrated sulfuric acid, and tert-butyl nitrite (0.23 g, 2.2 mmol) was slowly added dropwise to the reaction solution. The mixture was stirred at -5 ° C for 30 minutes, and then the reaction solution was poured into ice water, filtered, washed and dried to obtain the target product I (yield: 90%, 0.42 g), as shown in the photo. Figure 1 shown.

[0071] Example 2

[0072] 1.23 g (10.0 mmol) of 3,5-diamino-4-cyanopyrazole was dispersed in 20 mL of ethanol and stirred. Malononitrile (0.66 g, 10.0 mmol) and concentrated hydrochloric acid (1 mL) were then added to the solution in sequence. After the addition was completed, the mixture was stirred at 40°C for 1.5 hours, filtered, washed, and dried to obtain compound 2 (yield: 67%, 1.27 g).

[0073] Compound 2 (1.88 g, 10.0 mmol) was dispersed in 20 mL of acetonitrile solution, and 50% hydroxylamine solution (0.99 g, 15.0 mmol) was added dropwise to the solution. The temperature was raised to 80°C and heated for 12 hours. After the heating was completed, the reaction system was cooled, filtered, and dried to obtain compound 3 (yield: 89%, 1.98 g). Compound 3 (0.45 g, 2.0 mmol) was then added to 10 mL of acetic acid, and sodium nitrite (0.15 g, 2.2 mmol) was slowly added dropwise to the reaction solution. The mixture was stirred at 0°C for 3 hours, and then the reaction solution was poured into ice water, filtered, washed, and dried to obtain the target product I (yield: 86%, 2.00 g). The photo is shown as follows. Figure 1 shown.

[0074] Example 3

[0075] 1.23 g (10.0 mmol) of 3,5-diamino-4-cyanopyrazole was dispersed in 20 mL of methanol and stirred. Then, 3,3-diethoxypropionitrile (1.43 g, 10.0 mmol) and acetic acid (1 mL) were added to the solution in sequence. After the addition was completed, the mixture was stirred at 50°C for 3 hours, then cooled, filtered, washed, and dried to obtain compound 2a (yield: 85%, 1.47 g).

[0076] Compound 2a (1.73 g, 10.0 mmol) was dispersed in 20 mL of ethanol solution, and 40% hydroxylamine solution (1.24 g, 15.0 mmol) was added dropwise to the solution. The temperature was raised to 70°C and heated for 5 hours. After heating, the reaction system was cooled, filtered, and dried to obtain compound 3a (yield: 83%, 1.72 g). Compound 3a (0.42 g, 2.0 mmol) was then added to 10 mL of concentrated sulfuric acid, and nitrosylsulfuric acid (0.28 g, 2.2 mmol) was slowly added dropwise to the reaction solution. The mixture was stirred at 5°C for 60 minutes, and the reaction solution was poured into ice water, filtered, washed, and dried to obtain the target product II (yield: 83%, 0.36 g).

[0077] Example 4

[0078] 1.23 g (10.0 mmol) of 3,5-diamino-4-cyanopyrazole was dispersed in 20 mL of ethanol and stirred. 3,3-diethoxypropionitrile (1.43 g, 10.0 mmol) and concentrated hydrochloric acid (1 mL) were then added to the solution in sequence. After the addition was completed, the mixture was stirred at 70°C for 2 hours, then cooled, filtered, washed, and dried to obtain compound 2a (yield: 89%, 1.54 g).

[0079] Compound 2a (1.73 g, 10.0 mmol) was dispersed in 20 mL of methanol solution, and 50% hydroxylamine solution (0.99 g, 15.0 mmol) was added dropwise to the solution. The temperature was raised to 75°C and heated for 8 hours. After heating, the reaction system was cooled, filtered, and dried to obtain compound 3a (yield: 85%, 1.76 g). Compound 3a (0.42 g, 2.0 mmol) was then added to 10 mL of concentrated hydrochloric acid, and sodium nitrite (0.15 g, 2.2 mmol) was slowly added dropwise to the reaction solution. The mixture was stirred at 0°C for 90 minutes, and then the reaction solution was poured into ice water, filtered, washed, and dried to obtain the target product II (yield: 80%, 0.35 g).

[0080] The target product I obtained in Example 1 was subjected to spectral analysis, as shown in FIG. Figure 2 and Figure 3 As shown, the test results are as follows: 1 HNMR(DMSO-d6,500MHz)δ:9.69(s,2H),8.81(s,2H),7.93(s,2H),5.85(s,1H). 13 CNMR(DMSO-d6,125MHz)δ:161.1,152.5,148.6,145.7,144.9,85.7,78.8.IR(KBr,ν / cm –1 ):3443,3025,1682,1638,1547,1370,1276,1191,1134,1074,998,841,814,757,599,557. Elemental analysis C7H7N9O: Calculated value (%): C 36.05, H 3.03, N 54.06. Found value (%): C 36.26, H 3.12, N 53.87. The initial thermal decomposition temperature of the compound is 195 ° C (such as Figure 4 The density is 1.81 g·cm –3 , the formation enthalpy is 500.2 kJ mol –1 The theoretical detonation velocity is 8076 m s –1 , explosion pressure is 21.5Gpa, explosion heat is 2751kJ kg –1 , exhibiting good detonation performance. Impact sensitivity: >40J, friction sensitivity: >360N. Can be used as a heat-resistant explosive.

[0081] The target product II obtained in Example 3 was subjected to spectral analysis, as shown in FIG. Figure 5 and Figure 6 As shown, the test results are as follows: 1 HNMR(CF3COOD-d,500MHz)δ:8.65(d,1H),7.28(d,1H). 13C NMR(CF3COOD-d,125MHz)δ:154.2,154.4,147.0,145.5,140.2,99.5,88.2.IR(KBr,ν / cm –1 ):3237,2849,1657,1557,1469,1407,1363,1320,1245,1208,1132,1039,863,818,769,598,545. Elemental analysis C7H6N8O: Calculated value (%): C 38.54, H 2.77, N 51.36. Found value (%): 38.41, H 2.68, N 51.52. The initial thermal decomposition temperature of the compound is 223 ° C (such as Figure 7 The density is 1.78 g·cm –3 , the formation enthalpy is 519.0 kJ mol –1 The theoretical detonation velocity is 7691 m s –1 , explosion pressure is 19.7Gpa, explosion heat is 2950kJ kg –1 , impact sensitivity: >40J, friction sensitivity: >360N. Can be used as heat-resistant explosive.

[0082] Table 1 Physicochemical properties and energy performance parameters of compounds I and II

[0083]

[0084] a Test density (25℃), b Initial decomposition temperature, c Enthalpy of formation, d Theoretical calculation of detonation velocity, e Theoretical calculation of explosion pressure, f Impact sensitivity, g Friction sensitivity, h Hot.

[0085] Although the present invention is described herein with reference to illustrative implementations of the present invention, the above embodiments are merely preferred embodiments of the present invention, and the implementation methods of the present invention are not limited to the above embodiments. It should be understood that those skilled in the art can design many other modifications and implementations, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. An energetic compound I, characterized in that It is named 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide, and its structural formula is:

2. An energetic compound II, characterized in that It is named 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide, and its structural formula is:

3. A method for synthesizing an energetic compound I, characterized in that: include: (1) reacting 3,5-diamino-4-cyanopyrazole (1) with malononitrile under the action of an acid to prepare a compound 2,5,7-triamino-3-cyanopyrazolo[1,5-a]pyrimidine (2); (2) a step of reacting 2,5,7-triamino-3-cyanopyrazolo[1,5-a]pyrimidine (2) in a hydroxylamine solution to prepare compound (Z)-2,5,7-triamino-3-aminoximopyrazolo[1,5-a]pyrimidine (3); (3) reacting (Z)-2,5,7-triamino-3-aminoximinopyrazolo[1,5-a]pyrimidine (3) with a diazotizing agent to prepare the target product 4,6,8-triaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (I); 4. A method for synthesizing an energetic compound II, characterized in that: include: (1) reacting 3,5-diamino-4-cyanopyrazole (1) with 3,3-diethoxypropionitrile under the action of an acid to prepare a compound 2,7-diamino-3-cyanopyrazolo[1,5-a]pyrimidine (2a); (2) a step of reacting 2,7-diamino-3-cyanopyrazolo[1,5-a]pyrimidine (2a) in a hydroxylamine solution to prepare compound (Z)-2,7-diamino-3-aminoximopyrazolo[1,5-a]pyrimidine (3a); (3) a step of reacting (Z)-2,7-diamino-3-aminoximinopyrazolo[1,5-a]pyrimidine (3a) with a diazotizing agent to prepare 4,8-diaminopyrimido[1',2':1,5]pyrazolo[3,4-d][1,2,3]triazine 3-oxide (II); 5. The method according to claim 3 or 4, wherein: In step (1), the acid is any one of formic acid, acetic acid and hydrochloric acid; the reaction temperature is 40 to 80° C.; and the reaction time is 60 to 180 minutes.

6. The method according to claim 3 or 4, wherein: In step (2), the reaction is carried out in the presence of an organic solvent, which is any one of methanol, ethanol and acetonitrile; the reaction temperature is 60-80° C., and the reaction time is 3-12 hours.

7. The method according to claim 3 or 4, characterized in that In step (3), the diazotizing agent is any one of tert-butyl nitrite, nitrosylsulfuric acid and sodium nitrite; the reaction is carried out in the presence of an acid, which is any one of sulfuric acid, hydrochloric acid and acetic acid; in step (3), the reaction temperature is -5 to 5°C, and the reaction time is 30 to 180 minutes.

8. Use of the energetic compound I as claimed in claim 1 as a heat-resistant explosive.

9. Use of the energetic compound II as claimed in claim 1 as a heat-resistant explosive.

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