Synthesis method of dihydroxylamine 6, 6 '-dinitramine-3, 3'-azo-1, 2, 4 triazolo [4, 3-b] [1, 2, 4, 5] tetrazine

Abstract

The invention discloses a synthesis method of dihydroxylamine 6, 6 '-dinitramine-3, 3'-azo-1, 2, 4 triazolo [4, 3-b] [1, 2, 4, 5] tetrazine, and relates to the technical field of chemical synthesis. The method comprises the following steps: by taking 3, 6-bis (3, 5-dimethylpyrazole)-1, 2, 4, 5-tetrazine as a substrate, reacting with a nucleophilic reagent hydrazine hydrate under a weakly alkaline condition to prepare a compound 2; under an acidic condition, carrying out [3 + 2] cyclization reaction on the compound 2 and cyanogen bromide to generate a compound 3; performing oxidative coupling, ammoniation and nitration on the compound 3 to obtain a precursor compound 6; and carrying out direct acid-base neutralization on the precursor compound 6 and a hydroxylamine aqueous solution to generate a target compound. The synthesis method is simple, the target compound is generated through direct acid-base neutralization of 6, 6 '-dinitramine-3, 3'-azo-1, 2, 4 triazolo [4, 3-b] [1, 2, 4, 5] tetrazine and hydroxylamine, the reaction yield is high, and ten-gram-level batch production can be achieved.

Description

Technical Field

[0001] The invention belongs to the field of energetic materials and relates to a method for synthesizing dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine. Background Art

[0002] In the study of energetic materials, tetrazines are one of the most comprehensively studied materials, and tetrazines fused ring energetic materials also have great research potential. Tetrazines fused ring compounds have multiple rings and usually exist in a coplanar state, with a conjugated system, thus showing higher density and better stability. Due to the presence of ring tension, they have a higher positive formation enthalpy, thus showing more amazing detonation performance (Zhu Wangying. Synthesis and performance research based on tetrazines fused ring energetic compounds [D]. Nanjing University of Science and Technology, 2020.). In the study of energetic materials, nitro groups are often introduced into the synthesis of compounds as a group to improve the oxygen balance of the compound system, and can significantly increase the density of the compound, thereby improving the detonation performance (Zhou Yang, Long Xinping, Wang Xin, etc. New progress in the study of high nitrogen energetic compounds [J]. Energetic Materials, 2006 (04): 315-320.). Tetrazines fused ring energetic materials usually appear in the form of energetic organic salts, energetic organics, energetic metal salts and energetic complexes.

[0003] Nowadays, tetrazine-based energetic materials have been widely reported. The dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine synthesized by Jean'ne M.Shreeve's research group has a density of 1.99 g / cm 3 , with a detonation velocity of 10223 m / s, but the reported synthesis scale remains at the milligram level, and large-dose synthesis cannot be carried out, which has become a fatal drawback of its application. In addition, the target product needs to be obtained through an intermediate silver salt, and the synthesis route is complicated and cumbersome (Hu L, Yin P, Zhao G, et al. Conjugated Energetic Salts Based on Fused Rings: Insensitive and Highly Dense Materials[J]. Journal of the American Chemical Society, 2018, 140(44): 15001-15007.). Summary of the invention

[0004] The object of the present invention is to provide a simple and scalable method for synthesizing dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine.

[0005] The technical solution for achieving the purpose of the present invention is as follows:

[0006] The synthesis method of the synthesis method of dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine is as follows:

[0007] The specific steps are as follows:

[0008] (1) Add a hydrazine hydrate solution dropwise to an acetonitrile suspension of 3,6-di(3,5-dimethylpyrazole)-1,2,4,5-tetrazine (Compound 1), filter after the reaction, wash with toluene, and dry to obtain 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazine-1,2,4,5-tetrazine (Compound 2);

[0009] (2) dissolving 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4,5-tetrazine in an acid aqueous solution, adding cyanogen bromide, stirring at room temperature until the reaction is complete, filtering and washing with ice water, and drying to obtain 3-amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 3);

[0010] (3) a sodium hypochlorite solution with a concentration of 7.5 wt.% was added dropwise to a water suspension of 3-amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, and the mixture was reacted for 30 min to 1 h. After the reaction, the mixture was washed with ice water and filtered to obtain 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 4);

[0011] (4) Add 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, acetonitrile and an aminating agent into a pressure reactor, heat to 80-100°C for sufficient reaction, cool to room temperature after the reaction is completed, filter the solid, wash with ether and dry to obtain 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 5);

[0012] (5) Add 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine to pure nitric acid or fuming nitric acid, stir at a low temperature of -5 to 0°C, and after the reaction is complete, pour the solution into crushed ice, filter, wash with cold water, and air-dry to obtain 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 6);

[0013] (6) 6,6'-dinitroxy-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine was dissolved in acetonitrile, and an aqueous solution of hydroxylamine was added dropwise at a low temperature of -40 to -20°C. After the addition was complete, the mixture was filtered, and the filter cake was washed with acetonitrile and ethyl acetate, and dried naturally in air to obtain dihydroxyamine 6,6'-dinitroxy-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 7).

[0014] Preferably, in step (1), the reaction temperature is 15-25° C., the reaction time is 30 min, and the concentration of the hydrazine hydrate solution is 40 wt.%-85 wt.%.

[0015] Preferably, in step (2), the reaction temperature is 20-25° C., the reaction time is 24 h, the acid is hydrochloric acid or sulfuric acid, and the concentration of the acid aqueous solution is 15 wt.%.

[0016] Preferably, in step (3), the reaction temperature is 10 to 40°C, more preferably 15 to 20°C.

[0017] Preferably, in step (4), the aminating agent is methanolic ammonia, ethanolic ammonia or aqueous ammonia; and the molar ratio of 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine to the aminating agent is 1:3.7.

[0018] Preferably, in step (6), the reaction temperature is -40 to -30°C, the reaction time is 3 hours, and the concentration of the hydroxylamine aqueous solution is 25 wt.% to 75 wt.%, more preferably 50 wt.%.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] (1) The present invention generates dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (target compound) by direct acid-base neutralization of 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (compound 6), and hydroxylamine, and the reaction yield is very high, and a large amount of synthesis can be achieved, and mass production of ten grams can be achieved.

[0021] (2) The method of the present invention has easy synthesis conditions, simple steps and considerable reaction yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 1HNMR (DMSO-d6) spectrum of 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 4);

[0023] Figure 2 13CNMR (DMSO-d6) spectrum of 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 4);

[0024] Figure 3 1H NMR (DMSO-d6) spectrum of 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 5);

[0025] Figure 4 13C NMR (DMSO-d6) spectrum of 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 5);

[0026] Figure 5 1HNMR (DMSO-d6) spectrum of 6,6'-dinitramido-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 6);

[0027] Figure 6 13CNMR (DMSO-d6) spectrum of 6,6'-dinitramido-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 6);

[0028] Figure 7 1H NMR (DMSO-d6) spectrum of dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 7);

[0029] Figure 8 13C NMR (DMSO-d6) spectrum of dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 7);

[0030] Fig. 9The crystal structure diagram of dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (Compound 7). DETAILED DESCRIPTION

[0031] The present invention is further described below in conjunction with specific embodiments and drawings.

[0032] Example 1

[0033] (1) Synthesis of 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4,5-tetrazine:

[0034] At room temperature, 85wt.% hydrazine hydrate solution (0.05mmol) was added dropwise to a suspension of 3,6-di(3,5-dimethylpyrazole)-1,2,4,5-tetrazine (13.5g, 50mmol) in acetonitrile (150mL). After reacting for 30min, the mixture was filtered, washed with toluene and dried in air to obtain 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazine-1,2,4,5-tetrazine with a yield of 93%.

[0035] Compound structure analysis:

[0036] 1HNMR (500MHz, DMSO-d6): δ2.21(s,3H),2.37(s,3H),4.60(s,2H),6.17(s,1H),9.75(s,1H)ppm;

[0037] 13C NMR (126MHz, DMSO-d6): δ12.0, 13.2, 108.3, 141.2, 149.9, 156.95, 162.9ppm.

[0038] (2) Synthesis of 3-amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine:

[0039] At room temperature, 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazine-1,2,4,5-tetrazine (2.06 g, 10 mmol) was added to 1N hydrochloric acid (30 mL), and then cyanogen bromide (1.06 g, 10 mmol) was added, and the mixture was stirred for 24 hours. After the reaction, the purple precipitate was filtered, washed with ice water, and air-dried to obtain 3-amino-6-(3,5-dimethylpyrazole)-1,2,4 triazolo[4,3-b][1,2,4,5]tetrazine with a yield of 65%.

[0040] Compound structure analysis:

[0041] 1H NMR (500MHz, DMSO-d6): δ2.25(s,3H),2.60(s,3H),6.28(s,1H),7.60(s,2H)ppm;

[0042] 13C NMR (126MHz, DMSO-d6): δ13.0, 13.1, 110.4, 143.7, 149.2, 149.7, 150.0, 152.1ppm.

[0043] (3) Synthesis of 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine:

[0044] 3-Amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (2.31 g, 10 mmol) was suspended in 50 mL of deionized water, and a 7.5 wt.% aqueous sodium hypochlorite solution was slowly added dropwise at room temperature until the color of the solution changed from purple to yellow. The mixture was reacted for 30 min, and then washed with ice water and filtered to obtain 10 g of yellow solid 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine with a yield of 79.5%.

[0045] Compound structure analysis:

[0046] 1 HNMR (500MHz, DMSO-d6): δ2.33(s,3H),2.69(s,3H),6.46(s,1H)ppm;

[0047] 13 C NMR (126MHz, DMSO-d6): δ12.5, 13.8, 111.9, 144.2, 151.0, 151.3, 153.91, 153.94ppm.

[0048] (4) Synthesis of 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine:

[0049] Add yellow solid 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4 triazolo[4,3-b][1,2,4,5]tetrazine (1.37 g, 3 mmol) and acetonitrile (50 mL) into a 100 mL pressure reactor and fully dissolve it. Then introduce 7 M methanolic ammonia (1.6 mL, 11.2 mmol, the molar ratio of the raw material to it is 1:3.7) into the container through a syringe. Heat the reactor to 90 ° C, react for 4 hours, and then cool to room temperature. The solid is filtered, washed with ether and dried to obtain 0.79 g of compound 6,6'-diamino-3,3'-azo-1,2,4 triazolo[4,3-b][1,2,4,5]tetrazine, with a yield of 88%.

[0050] Compound structure analysis:

[0051] 1 HNMR (500MHz, DMSO-d6): δ8.59(s,4H)ppm;

[0052] 13 C NMR (126MHz, DMSO-d6): δ151.1,158.3ppm.

[0053] (5) Synthesis of 6,6'-dinitramido-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine:

[0054] Slowly add 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (0.5 g) to pure nitric acid (5 mL) and stir at a low temperature of -5 ° C. After complete addition, the reaction mixture is stirred for another 3 hours at the same temperature. After the reaction is completed, the solution is poured into crushed ice. The precipitate is filtered, rinsed with cold water, and air-dried to obtain a yellow solid 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (0.47 g) with a yield of 72%.

[0055] Compound structure analysis:

[0056] 1 HNMR (500MHz, DMSO-d6): δ5.50(s,2H)ppm;

[0057] 13 C NMR (126MHz, DMSO-d6): δ150.3, 151.6, 158.2ppm.

[0058] (6) Synthesis of dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine:

[0059] 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (0.39 g, 1 mmol) was dissolved in 20 mL of acetonitrile. A 50 wt.% aqueous solution of hydroxylamine (0.5 g) was diluted in an equal volume of acetonitrile and slowly added dropwise at -40°C, and the reaction temperature was maintained. After the addition was completed, the mixture was quickly filtered, and the filter cake was washed with acetonitrile and ethyl acetate, and dried naturally in the air to obtain the final product, dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine 0.44 g, with a yield of 96.5%.

[0060] Compound structure analysis:

[0061] 1 HNMR (500MHz, DMSO-d6): δ9.84(s,1H)10.03(s,3H)ppm;

[0062] 13 C NMR (126MHz, DMSO-d6): δ149.9, 151.7, 160.7ppm.

[0063] Example 2

[0064] This embodiment is substantially the same as Embodiment 1, except that:

[0065] The concentrations of hydrazine hydrate selected in step (1) are 40wt.%, 65wt.%, and 80wt.%, respectively, and the yields of the intermediate product 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazine-1,2,4,5-tetrazine are 62%, 75%, and 88%, respectively.

[0066] Example 3

[0067] This embodiment is substantially the same as Embodiment 1, except that:

[0068] The acid selected in step (2) is sulfuric acid, the reaction time is 36 hours, and the yield of the intermediate 3-amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine is 59.3%.

[0069] Example 4

[0070] This embodiment is substantially the same as Embodiment 1, except that:

[0071] The sodium hypochlorite concentration selected in step (3) is 7.5wt.%, the reaction time is 1h, and the yield of the intermediate product 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine is 49.6%.

[0072] Example 5

[0073] This embodiment is substantially the same as Embodiment 1, except that:

[0074] In step (4), the aminating agent is ethanol ammonia or aqueous ammonia, and the yield of the intermediate product 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine is 52%.

[0075] Example 6

[0076] This embodiment is substantially the same as Embodiment 1, except that:

[0077] In step (5), 5 mL of fuming nitric acid was used for nitration reaction, and the yield of the intermediate product 6,6'-dinitramido-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine was 68.4%.

[0078] Example 7

[0079] This embodiment is substantially the same as Embodiment 1, except that:

[0080] In step (6), compound 6 is directly neutralized with a hydroxylamine aqueous solution at -20°C to generate the target product, dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, with a yield of 62.7%.

[0081] Example 8

[0082] This embodiment is substantially the same as Embodiment 1, except that:

[0083] Step (6) is a 10g-scale enlargement operation, and the steps are as follows: 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine (11.7 g, 30 mmol) is dissolved in 560 mL of acetonitrile, and a 50 wt.% hydroxylamine aqueous solution (4.5 g, 68 mmol) is diluted in an equal volume of acetonitrile and slowly added dropwise at -40°C, and the reaction temperature is maintained. After the addition is completed, the mixture is quickly filtered, the filter cake is washed with acetonitrile and ethyl acetate, and dried naturally in air to obtain 12.1 g of the final product, dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, with a yield of 88.5%.

[0084] Comparative Example 1

[0085] This comparative example is substantially the same as Example 1, except that:

[0086] In step (1), the 1,2,4,5-tetrazine compound with disubstituted 3,6 positions of the substrate is 3-(3,5-dimethylpyrazole)6-chloro-1,2,4,5-tetrazine, and the yield of the intermediate product 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4,5-tetrazine is 21.5%, which is relatively low.

[0087] Comparative Example 2

[0088] This comparative example is substantially the same as Example 1, except that:

[0089] The concentration of sodium hypochlorite selected in step (3) is 5 wt.%, and the yield of the intermediate product 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine is 19.3%, which is relatively low.

[0090] Comparative Example 3

[0091] This comparative example is substantially the same as Example 1, except that:

[0092] In step (4), the molar ratio of 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine to methanol ammonia is 1:4.2, and the specific amounts used are 1 g and 1.31 mL. The yield of the intermediate product 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine is 21.6%, which is relatively low.

[0093] Comparative Example 4

[0094] This comparative example is substantially the same as Example 1, except that:

[0095] The sodium hypochlorite concentration selected in step (3) was 15 wt.%, the reaction failed, and the yield of the intermediate product 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine was 0%.

Claims

1. A method for synthesizing dihydroxyamine 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, It is characterized in that The specific steps are as follows: (1) Add a hydrazine hydrate solution dropwise to an acetonitrile suspension of 3,6-di(3,5-dimethylpyrazole)-1,2,4,5-tetrazine, filter after the reaction is complete, wash with toluene, and dry to obtain 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazine-1,2,4,5-tetrazine; (2) dissolving 3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazino-1,2,4,5-tetrazine in an acid aqueous solution, adding cyanogen bromide, stirring at room temperature until the reaction is complete, filtering and washing with ice water, and drying to obtain 3-amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine; (3) Add a 7.5 wt.% sodium hypochlorite solution to a water suspension of 3-amino-6-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, and react for 30 min to 1 h. After the reaction, wash with ice water and filter to obtain 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine; (4) Add 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine, acetonitrile and an aminating agent into a pressure reactor, heat to 80-100°C for sufficient reaction, cool to room temperature after the reaction is completed, filter the solid, wash with ether and dry to obtain 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine; (5) Add 6,6'-diamino-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine to pure nitric acid or fuming nitric acid, stir at a low temperature of -5 to 0°C, and after the reaction is complete, pour the solution into crushed ice, filter, wash with cold water, and air-dry to obtain 6,6'-dinitramine-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine; (6) Dissolve 6,6'-dinitroxy-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine in acetonitrile, add dropwise hydroxylamine aqueous solution at -40 to -20°C, filter after completion of the addition, wash the filter cake with acetonitrile and ethyl acetate, and dry naturally in air to obtain dihydroxyamine 6,6'-dinitroxy-3,3'-azo-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine.

2. The synthesis method according to claim 1, It is characterized in that In step (1), the reaction temperature is 15-25° C., the reaction time is 30 min, and the concentration of the hydrazine hydrate solution is 40 wt.%-85 wt.%.

3. The synthesis method according to claim 1, It is characterized in that In step (2), the reaction temperature is 20-25° C. and the reaction time is 24 h.

4. The synthesis method according to claim 1, It is characterized in that In step (2), the acid is hydrochloric acid or sulfuric acid, and the concentration of the acid aqueous solution is 15 wt.%.

5. The synthesis method according to claim 1, It is characterized in that In step (3), the reaction temperature is 10-40°C.

6. The synthesis method according to claim 1, It is characterized in that In step (3), the reaction temperature is 15-20°C.

7. The synthesis method according to claim 1, It is characterized in that In step (4), the aminating agent is methanolic ammonia, ethanolic ammonia or aqueous ammonia; the molar ratio of 6,6'-bis-(3,5-dimethylpyrazole)-1,2,4-triazolo[4,3-b][1,2,4,5]tetrazine to the aminating agent is 1:3.

7.

8. The synthesis method according to claim 1, It is characterized in that In step (6), the reaction temperature is -40~-30°C and the reaction time is 3h.

9. The synthesis method according to claim 1, It is characterized in that In step (6), the concentration of the hydroxylamine aqueous solution is 25 wt.% to 75 wt.%.

10. The synthesis method according to claim 1, It is characterized in that In step (6), the concentration of the hydroxylamine aqueous solution is 50 wt.%.

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