3, 4-diazido ethoxy furazan compound as well as preparation method and application thereof

Abstract

The invention discloses a 3, 4-diazido ethyoxyl furazan compound and a preparation method and application thereof.The 3, 4-diazido ethyoxyl furazan compound is obtained by taking 3, 4-dinitrofurazan, potassium hydroxide and 2-azido ethanol as raw materials and dichloromethane as a solvent, heating to 35-37 DEG C, reacting for 2-4 hours, and after the reaction is finished, washing, drying and concentrating under reduced pressure to obtain the 3, 4-diazido ethyoxyl furazan compound. The prepared compound belongs to an energetic plasticizer, has the characteristics of good thermal stability, low sensitivity, low glass transition temperature, good plasticizing effect and the like, and can be used in the fields of solid propellants, propellant powder and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of energetic materials and relates to an energetic plasticizer - 3,4-diazideethoxyfuroxan compound and a preparation method and application thereof. Background Art

[0002] Energetic plasticizer is one of the main functional additives that are indispensable in explosives. Its application can expand the use temperature range of explosives, improve the overall energy level, improve the processing technology, improve the low-temperature mechanical properties, and greatly reduce its vulnerability. Azide ether compounds are a class of excellent energetic materials and are important energetic materials for improving the energy level and low-temperature performance of energetic materials.

[0003] For example, in 2019, DING Feng, WANG Wei and ZHAO Baodong et al. published the azido linear ether plasticizer 1,5-diazide-3-oxapentane (AZDEGDN) compound and its properties in the article "Synthesis and Properties of Diazido Linear Ether Plasticizers" (Chinese Journal of Energetic Material, 2019, 27(12): 1043-1049), and its structure is shown in (II):

[0004]

[0005] The density of this compound is 1.135 g / cm 3 , thermal decomposition temperature (DSC) 249.3℃, glass transition temperature (Tg) <-100℃, sensitivity (characteristic drop height H 50 )64.6cm, formation enthalpy 912.5kJ / mol, but the compound has low density and low energy level, which affects the overall energy of explosive products in application.

[0006] Research results over the past half century have shown that furazan ring is a very effective structural unit in designing high energy density compounds composed of carbon, hydrogen, oxygen and nitrogen elements. Therefore, furazan plasticizers have good physical, chemical and detonation properties, such as high density, high thermal stability, good impact sensitivity, good oxygen balance, high detonation pressure and detonation velocity. In terms of thermal stability, density, sensitivity and detonation parameters, it is superior to nitroglycerin. As a potential energetic plasticizer designed and synthesized with a high-energy dense structural skeleton, furazan is very meaningful in the propellant formulation to greatly increase the energy of low-signal propellants and clean propellants. It has broad application prospects and great research and application value. Summary of the invention

[0007] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a 3,4-diazideethoxyfuroxan compound and a preparation method and application thereof, so as to solve the shortcomings of the current azidoether energetic plasticizers, such as low density, low energy, high sensitivity and poor stability, and to develop a new energetic plasticizer with high energy, low sensitivity and meeting the requirements of green cleaning.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0009] A 3,4-diazide ethoxy furazan compound, wherein the furazan is connected to an energetic azide group via an ethyl ether molecular chain, and the structural formula thereof is shown in (I):

[0010]

[0011] The preparation method of the 3,4-diazideethoxyfuroxan compound uses 3,4-dinitrofuroxan, potassium hydroxide, and 2-azidoethanol as raw materials, uses dichloromethane as solvent, provides alkaline conditions through KOH, removes the proton of 2-azidoethanol and activates the nitro group of furazan, completes the nucleophilic substitution reaction, and obtains the target product, comprising the following steps:

[0012] Potassium hydroxide, 2-azidoethanol and 3,4-dinitrofuroxan are added to dichloromethane, the temperature is raised to 35°C to 37°C, and the reaction is carried out for 2 to 4 hours. After the reaction is completed, the mixture is washed with water, dried and concentrated under reduced pressure to obtain a 3,4-diazideethoxyfuroxan compound.

[0013] The present invention also includes the following technical features:

[0014] Specifically, in the method, the molar ratio of 3,4-dinitrofurazan, potassium hydroxide, and 2-azidoethanol is 1:2.0-3.0:2.0-3.0.

[0015] Specifically, the time for heating to the set temperature in the above steps is 5 to 10 minutes.

[0016] The 3,4-diazideethoxyfuroxan compound prepared by the preparation method of the 3,4-diazideethoxyfuroxan compound is used as an energetic plasticizer in solid propellants and propellants.

[0017] Compared with the prior art, the present invention has the following technical effects:

[0018] (1) The compound of the present invention is composed of a furazan ring and an azidoethoxy group, and the nitrogen content reaches 42.0%. It has a high energy level and belongs to an energetic plasticizer. (2) The 3,4-diazideethoxyfurazan compound of the present invention has a low sensitivity, and the impact sensitivity reaches 50J, while the sensitivity of the comparative document AZDEGDN compound is only 12.92J. (3) The 3,4-diazideethoxyfurazan compound of the present invention has high thermal stability, and the thermal decomposition temperature (DSC) is 255.0℃, while the thermal decomposition temperature (DSC) of the comparative document AZDEGDN compound is 235℃. (4) The density of the 3,4-diazideethoxyfurazan compound of the present invention is 1.337g / cm 3 , while the density of the comparative document AZDEGDN compound is 1.135 g / cm 3 (5) The preparation process of the compound of the present invention is simple, safe and reliable. DETAILED DESCRIPTION

[0019] The present invention provides a 3,4-diazide ethoxy furazan compound and a preparation method and application thereof. In the 3,4-diazide ethoxy furazan compound, furazan is connected to an azide group via an ethyl ether bond, and the structural formula thereof is shown in (I):

[0020]

[0021] Synthesis route of 3,4-diazideethoxyfuroxan compounds:

[0022]

[0023] With 3,4-dinitrofurazan, potassium hydroxide and 2-azidoethanol as raw materials and dichloromethane as solvent, 3,4-dinitrofurazan undergoes aromatic nucleophilic substitution reaction with 2-azidoethanol under the catalysis of potassium hydroxide base to obtain 3,4-diazideethoxyfurazan.

[0024] The preparation method comprises the following steps:

[0025] Potassium hydroxide, 2-azidoethanol and 3,4-dinitrofuroxan are added to a solvent of dichloromethane, and the temperature is raised to 35°C to 37°C, and the reaction is carried out for 2 to 4 hours. After the reaction is completed, the mixture is washed with water, dried and concentrated under reduced pressure to obtain a 3,4-diazideethoxyfuroxan compound.

[0026] The time for heating to the set temperature in the above steps is 5 to 10 minutes.

[0027] In the method, the molar ratio of 3,4-dinitrofurazan, potassium hydroxide and 2-azidoethanol is 1:2.0-3.0:2.0-3.0.

[0028] Application of 3,4-diazideethoxyfuroxan compounds as energetic plasticizers in solid propellants and propellants.

[0029] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0030] Embodiment 1:

[0031] The present embodiment provides a 3,4-diazideethoxyfuroxan compound and a preparation method thereof. 2.18 g (0.025 mol) of 2-azidoethanol, 1.40 g (0.025 mol) of potassium hydroxide, 1.60 g (0.010 mol) of 3,4-dinitrofuroxan and 50 mL of dichloromethane are added to a reaction bottle, heated to 35° C. to 37° C., refluxed at this temperature for 3 h, washed with water, dried and concentrated under reduced pressure to obtain a light yellow liquid, i.e., 3,4-diazideethoxyfuroxan, 2.27 g, with a yield of 93.5%.

[0032] Structure identification:

[0033] Infrared spectrum: IR (KBr, cm -1 ),υ:2945,2886(-CH2-),2109(-N3),1602,1574,1453,1306

[0034] (-C=N)1276,1033(-COC-);

[0035] NMR spectrum: 1 H NMR (DMSO, 500MHz), δ: 3.76~3.78(t,2H,CH2), 4.49~4.50(t,2H,CH2), 2.51(p,H,DMSO); 13 C NMR (DMSO, 500MHz), δ: 156.45 (N=CO), 71.62 (CH2), 49.59 (CH2), 39.82~40.16 (m, C, DMSO).

[0036] Elemental analysis: Molecular formula C6H8N8O3

[0037] Theoretical value (%): C 30.00, H 3.36, N 46.65;

[0038] Found (%): C 30.08, H 3.47, N 45.77.

[0039] It was confirmed that the substance obtained by the above preparation method was 3,4-diazideethoxyfuroxan, with the molecular formula of C6H8N8O3.

[0040] Embodiment 2:

[0041] The present embodiment provides a 3,4-diazideethoxyfuroxan compound and a preparation method thereof. 1.74 g (0.020 mol) of 2-azidoethanol, 1.12 g (0.020 mol) of potassium hydroxide, 1.60 g (0.010 mol) of 3,4-dinitrofuroxan and 50 mL of dichloromethane are added to a reaction bottle, heated to 35° C. to 37° C., refluxed at this temperature for 3 h, washed with water, dried and concentrated under reduced pressure to obtain a light yellow liquid, i.e., 3,4-diazideethoxyfuroxan, 2.14 g, with a yield of 79.0%.

[0042] Embodiment 3:

[0043] The present embodiment provides a 3,4-diazideethoxyfuroxan compound and a preparation method thereof. 2.18 g (0.025 mol) of 2-azidoethanol, 1.40 g (0.025 mol) of potassium hydroxide, 1.60 g (0.010 mol) of 3,4-dinitrofuroxan and 50 mL of dichloromethane are added to a reaction bottle, heated to 35° C. to 37° C., refluxed at this temperature for 4 hours, washed with water, dried and concentrated under reduced pressure to obtain a light yellow liquid, i.e., 3,4-diazideethoxyfuroxan, 2.21 g, with a yield of 84.3%.

[0044] Embodiment 4:

[0045] The present embodiment provides a 3,4-diazideethoxyfuroxan compound and a preparation method thereof. 2.61 g (0.030 mol) of 2-azidoethanol, 1.68 g (0.030 mol) of potassium hydroxide, 1.60 g (0.010 mol) of 3,4-dinitrofuroxan and 50 mL of dichloromethane are added to a reaction bottle, heated to 35° C. to 37° C., refluxed at this temperature for 3 h, washed with water, dried and concentrated under reduced pressure to obtain a light yellow liquid, i.e., 3,4-diazideethoxyfuroxan, 2.24 g, with a yield of 91.4%.

[0046] Properties of 3,4-diazideethoxyfuroxan

[0047] (1) Physical and chemical properties

[0048] Appearance: Yellow liquid; Solubility: Soluble in acetone, dichloromethane, ethyl acetate, dimethyl sulfoxide (DMSO), dimethylformamide (DMF) and other solvents, insoluble in water, ethanol, etc.; Density: 1.337 g / cm 3 (20℃, density meter).

[0049] (2) Glass transition temperature and decomposition temperature

[0050] The glass transition temperature Tg of 3,4-diazideethoxyfuroxan is -63.4°C (DSC method), the melting point is 34.1°C (DSC method), and the decomposition temperature is 255.0°C (DSC method, pressure 2MPa).

[0051] (3) Sensitivity

[0052] Impact sensitivity: 50J; Test conditions: drop weight: 10Kg, dosage: 30mg.

[0053] Application of 3,4-diazideethoxyfuroxan of the present invention:

[0054] The 3,4-diazideethoxyfuroxan compound of the present invention has the characteristics of low sensitivity, good thermal stability and high nitrogen content, and can be widely used in propellants, propellants and mixed explosives as an energetic plasticizer.

Claims

1. A 3,4-diazideethoxyfuroxan compound, characterized in that: In the compound, furazan is connected to the energetic azide group through an ethyl ether molecular chain, and its structural formula is shown in (I):

2. The method for preparing the 3,4-diazideethoxyfuroxan compound according to claim 1, characterized in that: The method uses 3,4-dinitrofurazan, potassium hydroxide, and 2-azidoethanol as raw materials, uses dichloromethane as solvent, provides alkaline conditions through KOH, removes the proton of 2-azidoethanol and activates the nitro group of furazan, completes the nucleophilic substitution reaction, and obtains the target product, including the following steps: Potassium hydroxide, 2-azidoethanol and 3,4-dinitrofuroxan are added to dichloromethane, the temperature is raised to 35°C to 37°C, and the reaction is carried out for 2 to 4 hours. After the reaction is completed, the mixture is washed with water, dried and concentrated under reduced pressure to obtain a 3,4-diazideethoxyfuroxan compound.

3. The method for preparing the 3,4-diazideethoxyfuroxan compound according to claim 2, characterized in that: In the method, the molar ratio of 3,4-dinitrofurazan, potassium hydroxide and 2-azidoethanol is 1:2.0-3.0:2.0-3.

0.

4. The method for preparing the 3,4-diazideethoxyfuroxan compound according to claim 2, characterized in that: The time for heating to the set temperature in the above steps is 5 to 10 minutes.

5. Use of the 3,4-diazideethoxyfuroxan compound obtained by the preparation method of the 3,4-diazideethoxyfuroxan compound according to claim 2 as an energetic plasticizer in solid propellants and propellants.

Images