3, 6-bis (4-N-nitrofurazanyl)-1, 2, 4, 5-tetrazine compound and synthesis method thereof

Abstract

The invention discloses a 3, 6-bis (4-N-nitro furazanyl)-1, 2, 4, 5-tetrazine compound and a synthesis method thereof, the 3, 6-bis (4-N-nitro furazanyl)-1, 2, 4, 5-tetrazine compound has a cis-structure or a trans-structure as shown in the specification: the 3, 6-bis (4-amino furazanyl)-1, 2, 4, 5-tetrazine synthesized by the invention belongs to an energetic compound in which 3 and 6 sites of 1, 2, 4, 5-tetrazine are connected with a furazan ring, and the 3, 6-bis (4-amino furazanyl)-1, 2, 4, 5-tetrazine can be used as an energy-containing compound. A new variety can be provided for the 1, 2, 4, 5-tetrazine energetic compound; according to the method disclosed by the invention, the cis / trans-3, 6-bis (4-N-nitrofurazanyl)-1, 2, 4, 5-tetrazine can be obtained at the same time. According to the method, trans-3, 6-bis (4-N-nitrofurazan)-1, 2, 4, 5-tetrazine and cis / trans-3, 6-bis (4-N-nitrofurazan)-1, 2, 4, 5-tetrazine can be obtained at the same time through different nitration reagents, the blank of cis-trans configuration energetic materials is filled, and basic research data is provided for cis-trans isomer eutectic energetic materials.

Description

Technical Field

[0001] The present invention belongs to the field of energetic material preparation, and in particular relates to a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound and a synthesis method thereof. Background Art

[0002] In the field of energetic materials, 1,2,4,5-tetrazine ring is an important high-energy explosive unit. It has the advantages of high nitrogen content, high density, high formation enthalpy, good detonation performance, and environmental friendliness. Many scientific researchers at home and abroad have conducted research and exploration on it.

[0003] At present, many energetic compounds with 1,2,4,5-tetrazine connected to the 3,6 positions by rings, oxygen bridges, nitrogen bridges, and azole rings have been synthesized, but there have been no reports on the synthesis of energetic compounds connected to the furazan ring. However, as one of the important representative rings of energetic compounds, the furazan ring also has the advantages of high density, high formation enthalpy, and high detonation performance. If it can be connected to the 3,6 positions of 1,2,4,5-tetrazine and synthesized, it will be of great significance for the research and development of new 1,2,4,5-tetrazine energetic compounds. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the object of the present invention is to provide a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound and a synthesis method thereof, so as to solve the technical problem that the prior art lacks energetic compounds with furazan rings connected at the 3,6 positions of 1,2,4,5-tetrazine.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound having a cis structure or a trans structure as shown below:

[0007]

[0008] The present invention also protects a method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound, comprising the following steps:

[0009] Step 1, adding 1,4-dioxane to 3-amino-4-cyanofurazan, adding hydrazine acetate and a catalyst under stirring, stirring at room temperature, heating to 75-80° C., stirring at constant temperature for 22-26 hours, cooling and filtering, washing with 1,4-dioxane and distilled water in sequence to obtain 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine;

[0010] Step 2: adding dichloromethane and urea hydrogen peroxide complex to the obtained 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, cooling the reaction system to 0°C and stirring for 30 to 60 minutes; adding trifluoroacetic anhydride dropwise to the reaction system, reacting for 10 to 14 hours, then warming to room temperature and continuing to stir for 10 to 14 hours; filtering and washing to obtain 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine;

[0011] Step 3: adding the 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 to the mixed acid at 0-5° C., stirring for 30-40 minutes, then warming the reaction system to room temperature and stirring for 2-3 hours; pouring the reaction system into ice water; filtering the generated solid and recrystallizing it with distilled water to obtain trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine; the volume ratio of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine to the mixed acid is 1:20-40;

[0012] or,

[0013] At 0-5° C., the 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 is added to fuming nitric acid, the mixture is heated to room temperature and stirred for 2-3 hours, and the fuming nitric acid is removed under reduced pressure to obtain a crude compound; the obtained crude compound is recrystallized from distilled water to obtain cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine; the volume ratio of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine to the fuming nitric acid is 1:5-15.

[0014] Furthermore, the catalyst described in step 1 includes a Lewis acid metal catalyst and a non-metallic catalyst, wherein the Lewis acid metal catalyst is selected from any one of zinc trifluoromethanesulfonate, nickel trifluoromethanesulfonate, cerium trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, scandium trifluoromethanesulfonate and cuprous trifluoromethanesulfonate; and the non-metallic catalyst is selected from any one of sulfur powder, 3-mercaptopropionic acid, L-cysteine, 1,3-propanedithiol, 2-aminoethanethiol and thioacetic acid.

[0015] Furthermore, the molar ratio of 3-amino-4-cyanofurazan, 1,4-dioxane, hydrazine acetate and Lewis acid metal catalyst in step 1 is 1:5-20:1-10:0.01-0.1.

[0016] Furthermore, the molar ratio of 3-amino-4-cyanofurazan, 1,4-dioxane, hydrazine acetate and non-metallic catalyst in step 1 is 1:5-20:1-10:0.1-5.0.

[0017] Furthermore, the molar ratio of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, dichloromethane, urea hydrogen peroxide complex and trifluoroacetic anhydride in step 2 is 1:100-150:10-20:5-15.

[0018] Furthermore, the molar ratio of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, dichloromethane, urea hydrogen peroxide complex and trifluoroacetic anhydride in step 2 is 1:110:15:10.

[0019] Furthermore, the mixed acid in step 3 is prepared by mixing fuming nitric acid and concentrated sulfuric acid, and the molar ratio of the fuming nitric acid to the concentrated sulfuric acid is 1:1-10.

[0020] Furthermore, the mixed acid in step 3 is prepared by mixing fuming nitric acid and concentrated sulfuric acid, and the molar ratio of the fuming nitric acid to the concentrated sulfuric acid is 1:2.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine synthesized in the present invention is an energetic compound in which the 3 and 6 positions of 1,2,4,5-tetrazine are connected to the furazan ring, and can provide a new variety of 1,2,4,5-tetrazine energetic compounds.

[0023] (2) The method of the present invention can obtain trans-3,6-bis(4-N-nitrofuroxanyl)-1,2,4,5-tetrazine and cis / trans-3,6-bis(4-N-nitrofuroxanyl)-1,2,4,5-tetrazine by using different nitrating reagents, thus filling the gap in cis-trans configuration energetic materials and providing basic research data for cis-trans isomer cocrystal energetic materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The single crystal structure of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine in Example 1;

[0025] Figure 2 The structures of five solvate single crystals and one ansolvate single crystal of 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine in Example 1 are shown;

[0026] Figure 3 This is the single crystal structure of trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine in Example 1;

[0027] Figure 4This is a single crystal structure diagram of cis / trans 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine in Example 1. DETAILED DESCRIPTION

[0028] The present invention is further described below with reference to the following examples, the purpose of which is to provide a better understanding of the essential features of the present invention as embodied in the contents of the present invention. Therefore, the examples given should not be regarded as limiting the scope of protection of the present invention.

[0029] It should be noted that, unless otherwise specified, all raw materials in the present invention are raw materials known in the prior art.

[0030] The present invention provides a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound having a cis structure or a trans structure as shown below:

[0031]

[0032]

[0033] The synthetic route of 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine of the present invention is as follows:

[0034]

[0035] Among them, (a) is 3-amino-4-cyanofurazan, (b) is 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, (c) is 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine, (d) is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine, and (e) is cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0036] The synthesis method of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound of the present invention comprises the following steps:

[0037] Step 1, adding 1,4-dioxane to 3-amino-4-cyanofurazan, adding hydrazine acetate and a catalyst under stirring, stirring at room temperature, heating to 75-80° C., stirring at a constant temperature for 22-26 hours, then cooling to 18-25° C., filtering, washing with 1,4-dioxane and distilled water in sequence to obtain 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine;

[0038] Preferably, the catalyst comprises a Lewis acid metal catalyst and a non-metallic catalyst, wherein the Lewis acid metal catalyst is selected from any one of zinc trifluoromethanesulfonate, nickel trifluoromethanesulfonate, cerium trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, scandium trifluoromethanesulfonate and cuprous trifluoromethanesulfonate; and the non-metallic catalyst is selected from any one of sulfur powder, 3-mercaptopropionic acid, L-cysteine, 1,3-propanedithiol, 2-aminoethanethiol and thioacetic acid.

[0039] Preferably, the molar ratio of the 3-amino-4-cyanofurazan, 1,4-dioxane, hydrazine acetate and Lewis acid metal catalyst is 1:5-20:1-10:0.01-0.1.

[0040] Preferably, the molar ratio of the 3-amino-4-cyanofurazan, 1,4-dioxane, hydrazine acetate and non-metallic catalyst is 1:5-20:1-10:0.1-5.0.

[0041] Step 2: adding dichloromethane and urea hydrogen peroxide complex to the obtained 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, cooling the reaction system to 0°C and stirring for 30 to 60 minutes; adding trifluoroacetic anhydride dropwise to the reaction system, reacting for 10 to 14 hours, then warming to room temperature and continuing to stir for 10 to 14 hours; filtering and washing to obtain 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine;

[0042] Preferably, the molar ratio of the 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, dichloromethane, urea hydrogen peroxide complex and trifluoroacetic anhydride is 1:100-150:10-20:5-15.

[0043] Step 3: adding the 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 to the mixed acid at 0-5° C., stirring for 30-40 minutes, then warming the reaction system to room temperature and stirring for 2-3 hours; pouring the reaction system into ice water; filtering the generated solid and recrystallizing it with distilled water to obtain trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine; the volume ratio of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine to the mixed acid is 1:20-40;

[0044] or,

[0045] At 0-5° C., the 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 was added to fuming nitric acid, the mixture was heated to room temperature and stirred for 2-3 h, and the fuming nitric acid was removed under reduced pressure to obtain a crude compound; the obtained crude compound was recrystallized from distilled water to obtain cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0046] The volume ratio of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine to the fuming nitric acid is 1:5-15.

[0047] Preferably, the mixed acid is prepared by mixing fuming nitric acid and concentrated sulfuric acid, and the molar ratio of the fuming nitric acid to the concentrated sulfuric acid is 1:1-10.

[0048] Example 1

[0049] In accordance with the above technical scheme, this embodiment provides a method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound, comprising the following steps:

[0050] Step 1. 0.5 g, 4.55 mmol of 3-amino-4-cyanofurazan was placed in a 25 ml single-necked bottle, 5 ml of 1,4-dioxane was added, and 5.0 eq., 2.1 g of hydrazine acetate and 0.05 eq., 133.6 mg of cerium trifluoromethanesulfonate (as a catalyst) were added under stirring. After stirring at room temperature for 30 min, the temperature was raised to 80 ° C. and stirred at this temperature for 24 h. After TLC detection, it was determined that the raw materials were completely reacted; the temperature was cooled and filtered, and the mixture was washed with 5 mL of 1,4-dioxane and 10 mL of distilled water, respectively, to obtain 182.1 mg of a slightly yellow solid compound with a yield of 32%.

[0051] Structure identification:

[0052] NMR spectroscopy: 1 H NMR (400MHz, DMSO), δ: 9.53 (s, 2H), 6.23 (s, 4H)

[0053] 13 C NMR (101MHz, DMSO), δ: 154.86, 139.08, 137.48

[0054] HRMS(ESI):m / z calcd for C6H6N 10 O2+H + :251.0748[M+H] + :found:251.0751

[0055] HRMS(ESI):m / z calcd for C6H6N10O2+H+:251.0748[M+H]+:found:251.0751

[0056] The above structural identification data confirmed that the product is 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, and its single crystal structure is as follows: Figure 1 As shown;

[0057] Step 2: 338 mg, 1.43 mmol of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine was placed in a 25 mL single-necked bottle, 10 mL of dichloromethane and 15.0 eq., 1.91 g of urea hydrogen peroxide complex were added, the reaction system was cooled to 0°C and stirred for 30 min; 10.0 eq., 1.9 mL of trifluoroacetic anhydride was slowly added dropwise to the reaction system for about 15 min; the reaction was allowed to react at 0°C for 12 h, then warmed to room temperature and stirred for 12 h. TLC analysis showed that the reaction of the raw material was complete; the mixture was filtered and washed three times with 10 mL of distilled water to obtain 308.5 mg of a blood-red solid compound with a yield of 92%.

[0058] Structure identification:

[0059] NMR spectroscopy: 1 H NMR (400MHz, DMSO), δ: 3.53 (s, 4H)

[0060] 13 C NMR (101MHz, DMSO), δ: 158.75, 156.18, 141.39

[0061] HRMS(ESI):m / z calcd for C6H4N 10 O2+H + :249.0591[M+H] + :found:249.0593

[0062] The above structural identification data confirmed that the product is 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine, and its five solvate single crystals and one ansolvate single crystal structure are as follows: Figure 2 As shown;

[0063] Step 3. Slowly add 0.5 g, 2.015 mmol of 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 to a mixed acid consisting of 5.0 mL of fuming nitric acid (100%) and 10 mL of concentrated sulfuric acid at 0°C. After stirring at 0°C for 30 min, the reaction system is warmed to room temperature and stirred for 2 h. The reaction system is poured into 25 mL of ice water, the formed solid is filtered and recrystallized with distilled water to obtain 647.3 mg, 1.914 mmol, of a blood-red solid compound with a yield of 95%.

[0064] Structure identification:

[0065] NMR spectroscopy: 1 H NMR (600MHz, DMSO), δ: 12.77 (s, 2H)

[0066] 13 C NMR (151MHz, DMSO), δ: 159.08, 154.35, 147.04

[0067] Infrared spectroscopy: IR(film)ν max =3727.88,3443.67,2926.00,1615.94,1384.85,1313.84,1229.02,1141.53,1078.55,1054.94,1023.32,929.14,856.53,778.41,592.70cm -1

[0068] HRMS(ESI):m / z calcd for C6N 12 O6Na2+H + :382.9932[M+H] + :found:382.9932

[0069] The above structural identification data confirmed that the product is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine, and its single crystal structure is as follows: Figure 3 shown.

[0070] In this example, 0.4 g, 1.612 mmol of 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine was slowly added to 4.0 mL of fuming nitric acid (100%) at 0°C, then the temperature was raised to room temperature and stirred for 2 h. The fuming nitric acid was removed under reduced pressure to obtain a crude compound, which was recrystallized from distilled water to obtain 534.2 mg, 1.58 mmol, of a blood-red solid compound in a yield of 98%.

[0071] Structure identification:

[0072] NMR spectroscopy: 1 H NMR (600MHz, DMSO), δ: 6.57 (s, 2H)

[0073] 13 C NMR (151MHz, DMSO), δ: 159.28, 159.24, 154.80, 154.57,

[0074] 147.08(2C)

[0075] Infrared spectroscopy: IR(film)ν max =3453.26,2923.31,1619.62,1573.48,1452.25,1385.44,1308.06,1257.39,1233.23,1141.59,1115 .68,1080.23,1060.12,1023.78,888.38,873.82,853.67,830.71,755.59,593.81,581.03,505.27cm -1

[0076] HRMS(ESI):m / z calcd for C6N 12 O6Na2+H + :382.9932[M+H] + :found:382.9929

[0077] The above structural identification data confirmed that the product is cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine, and its single crystal structure is as follows: Figure 4 shown.

[0078] The 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound of the present invention has a stable structure and contains both nitramine and tetrazine groups, showing promising application prospects in the field of energetic materials technology. Furthermore, the tetrazine group can undergo a cycloaddition reaction with compounds containing unsaturated double bonds, enabling its application in the non-isocyanate room-temperature curing molding of solid propellants.

[0079] Example 2

[0080] This example provides a method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound. The components and preparation method used in this example are substantially the same as those in Example 1, with the only difference being that the catalyst used in Step 1 is zinc trifluoromethanesulfonate (0.05 eq.). Calculated, the yield of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine is 9%.

[0081] In this embodiment, when a mixed acid is used, a blood-red product is finally obtained, which is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0082] When fuming nitric acid was used, a blood-red product was finally obtained, which was cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0083] Example 3

[0084] This example provides a method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound. The components and preparation method used in this example are substantially the same as those in Example 1, with the only difference being that the catalyst used in Step 1 is nickel trifluoromethanesulfonate (0.05 eq.). Calculated, the yield of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine is 14%.

[0085] In this embodiment, when a mixed acid is used, a blood-red product is finally obtained, which is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0086] When fuming nitric acid was used, a blood-red product was finally obtained, which was cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0087] Example 4

[0088] This example provides a method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound. The components and preparation method used in this example are substantially the same as those in Example 1, with the only difference being that the catalyst used in Step 1 is copper trifluoromethanesulfonate (0.05 eq.). Calculated, the yield of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine is 6%.

[0089] In this embodiment, when a mixed acid is used, a blood-red product is finally obtained, which is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0090] When fuming nitric acid was used, a blood-red product was finally obtained, which was cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0091] Example 5

[0092] This example provides a method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound. The components and preparation method used in this example are basically the same as those in Example 1, except that the catalyst used in step 1 is 3-mercaptopropionic acid (0.1 eq.). Calculated, the yield of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine is 20%.

[0093] In this embodiment, when a mixed acid is used, a blood-red product is finally obtained, which is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0094] When fuming nitric acid was used, a blood-red product was finally obtained, which was cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0095] Example 6

[0096] This example provides a method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound. The components and preparation method used in this example are basically the same as those in Example 1, with the only difference being that in step 1, the catalyst used is sulfur powder (4.0 eq.). Calculated, the yield of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine is 25%.

[0097] In this embodiment, when a mixed acid is used, a blood-red product is finally obtained, which is trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0098] When fuming nitric acid was used, a blood-red product was finally obtained, which was cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine.

[0099] It can be seen from Examples 1 to 6 that compound b is prepared by hydrazine acetate under catalyst conditions, and the catalyst plays a crucial role in the yield. Subsequently, compound c is obtained in high yield by oxidation under the conditions of an oxidant urea-hydrogen peroxide complex. Subsequently, energetic material compound d and mixture d / e are obtained under different nitrating reagent conditions.

[0100] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound, characterized in that: It has a cis or trans structure as shown below:

2. A method for synthesizing a 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound, characterized in that: The following steps are involved: Step 1, adding 1,4-dioxane to 3-amino-4-cyanofurazan, adding hydrazine acetate and a catalyst under stirring, stirring at room temperature, heating to 75-80° C., stirring at a constant temperature for 22-26 hours, then cooling to 18-25° C., filtering, washing with 1,4-dioxane and distilled water in sequence to obtain 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine; Step 2: adding dichloromethane and urea hydrogen peroxide complex to the obtained 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, cooling the reaction system to 0°C and stirring for 30 to 60 minutes; adding trifluoroacetic anhydride dropwise to the reaction system, reacting for 10 to 14 hours, then warming to room temperature and continuing to stir for 10 to 14 hours; filtering and washing to obtain 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine; Step 3: adding the 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 to the mixed acid at 0-5° C., stirring for 30-40 minutes, then warming the reaction system to room temperature and stirring for 2-3 hours; pouring the reaction system into ice water; filtering the generated solid and recrystallizing it with distilled water to obtain trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine; the volume ratio of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine to the mixed acid is 1:20-40; or, At 0-5° C., the 3,6-bis(4-aminofurazanyl)-1,2,4,5-tetrazine obtained in step 2 is added to fuming nitric acid, the mixture is heated to room temperature and stirred for 2-3 hours, and the fuming nitric acid is removed under reduced pressure to obtain a crude compound; the obtained crude compound is recrystallized from distilled water to obtain cis / trans-3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine; the volume ratio of the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine to the fuming nitric acid is 1:5-15.

3. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 2, wherein: The catalyst described in step 1 includes a Lewis acid metal catalyst and a non-metallic catalyst, wherein the Lewis acid metal catalyst is selected from any one of zinc trifluoromethanesulfonate, nickel trifluoromethanesulfonate, cerium trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, scandium trifluoromethanesulfonate and cuprous trifluoromethanesulfonate; and the non-metallic catalyst is selected from any one of sulfur powder, 3-mercaptopropionic acid, L-cysteine, 1,3-propanedithiol, 2-aminoethanethiol and thioacetic acid.

4. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 3, wherein: The molar ratio of 3-amino-4-cyanofurazan, 1,4-dioxane, hydrazine acetate and Lewis acid metal catalyst in step 1 is 1:5-20:1-10:0.01-0.

1.

5. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 3, wherein: The molar ratio of 3-amino-4-cyanofurazan, 1,4-dioxane, hydrazine acetate and non-metallic catalyst in step 1 is 1:5-20:1-10:0.1-5.

0.

6. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 3, wherein: The molar ratio of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, dichloromethane, urea hydrogen peroxide complex and trifluoroacetic anhydride in step 2 is 1:100-150:10-20:5-15.

7. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 2, wherein: The molar ratio of 3,6-bis(4-aminofurazanyl)-1,2,4,5-dihydrotetrazine, dichloromethane, urea hydrogen peroxide complex and trifluoroacetic anhydride described in step 2 is 1:110:15:

10.

8. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 2, wherein: The mixed acid in step 3 is prepared by mixing fuming nitric acid and concentrated sulfuric acid, and the molar ratio of the fuming nitric acid to the concentrated sulfuric acid is 1:1-10.

9. The method for synthesizing the 3,6-bis(4-N-nitrofurazanyl)-1,2,4,5-tetrazine compound according to claim 2, wherein: The mixed acid in step 3 is prepared by mixing fuming nitric acid and concentrated sulfuric acid, and the molar ratio of the fuming nitric acid to the concentrated sulfuric acid is 1:2.

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