Cage-shaped trinuclear pyrazole cuprous energetic complex with ultrahigh thermal stability and synthesis method thereof

Abstract

The invention discloses a cage-shaped trinuclear pyrazole cuprous energetic complex with ultrahigh thermal stability and a synthesis method thereof. The energetic complex is applied to an energetic material. 3-nitropyrazole and copper nitrate are mixed, the cage-shaped trinuclear pyrazole cuprous energetic complex is synthesized through self-assembly, and the triangular stable pi-pi stacking structure has high density, good thermal stability and low sensitivity and is not oxidized into bivalent copper after being stored in carrier air for a long time.

Description

Technical Field

[0001] This invention belongs to the field of energetic materials, specifically involving a method for preparing an energetic metal-organic framework crystal material (Cu-MOF) self-assembled from Cu(NO3)2 and 3-nitropyrazole. This invention is expected to have good application prospects in the field of heat-resistant energetic materials. Background Technology

[0002] The study of metal coordination polymers is at the forefront of modern inorganic chemistry. These polymers utilize metal ions as nodes and organic ligands as linkers, leveraging the varied geometric coordination of metal ions and the symmetry of organic ligands to assemble interesting topological structures under suitable conditions. This represents a new stage in supramolecular chemistry and is an important field in crystal engineering. Due to their unique structures, tunable properties, and potential applications in chemistry, metal coordination polymers have attracted widespread attention in coordination chemistry and materials science, showing promise for applications in sensors, gas storage, magnetic materials, and energetic materials. Notably, the high density, good thermal stability, and low sensitivity of metal coordination polymers have garnered increasing attention for their development in the field of energetic materials.

[0003] In the prior art, Zhiwen Ye et al. (New J. Chem., 2024, 48, 16331–16336) reported the synthesis of metal coordination polymers of triazolotriazine compounds coordinated with Cu(NO3)2, but these were coordinated with oxygen in the form of ionic salts and did not form a stable cage-like framework. This study combines the previously unreported triangular prism-shaped cage-like cuprous complex (Cu-MOF) with the field of energetic materials to explore the impact of its novel structure on performance. Summary of the Invention

[0004] The purpose of this invention is to provide an energetic metal coordination compound and its method for one-pot hydrothermal synthesis. This compound possesses a triangular prism-cage-like stable structure with an attractive π-π stacking structure between metal cations. The compound exhibits strong thermal stability.

[0005] In a first aspect, the present invention provides a cage-like trinuclear pyrazole copper(II) energetic complex (Cu-MOF) with ultra-high thermal stability, having the following structure:

[0006]

[0007] The preferred unit cell parameters for the cage-like trinuclear pyrazolium copper complex are: α = 92.716(4)°, β = 97.813(3)°, γ = 105.297(3)°, Z = 2, cell volume

[0008] In a second aspect, the present invention provides a method for synthesizing the cage-like trinuclear pyrazole cuprous energetic complex described in the first aspect, comprising the steps of mixing 3-nitropyrazole with copper nitrate and then self-assembling to synthesize a triangular prism-like cage-like cuprous complex.

[0009]

[0010] Preferably, it includes the following steps:

[0011] At a certain temperature, 3-nitropyrazole is dispersed in a reaction solvent, copper nitrate trihydrate is added, and after sonication, the mixture is reacted in a reaction vessel at a certain temperature. After natural cooling, it is centrifuged, filtered, washed, and dried to obtain Cu-MOF.

[0012] Preferably, the reaction temperature can be 90℃~100℃.

[0013] Preferably, the reaction solvent is a mixture of water, methanol and N,N-dimethylformamide in a volume ratio of 1:1:1.

[0014] Ideally, the reaction time can be 10-14 hours.

[0015] Thirdly, the present invention provides the use of the cage-like trinuclear pyrazole copper energized complex described in the first aspect as an initiating explosive.

[0016] Compared with the prior art, the present invention has significant advantages: the present invention synthesizes an attractive π-π stacking structure between metal cations, a structurally stable cage-like trinuclear pyrazolium copper energetic complex, which has high density, good thermal stability and low sensitivity, and is not oxidized to divalent copper in long-term storage in air. Further addition of energetic molecules to the structure is expected to synthesize energetic materials with good application value. Attached Figure Description

[0017] Figure 1 This is the crystal structure diagram of a cage-like trinuclear pyrazolium copper(II) energetic complex (Cu-MOF).

[0018] Figure 2 Image of a crystal sample of cage-like trinuclear pyrazolium copper(II) energetic complex (Cu-MOF).

[0019] Figure 3 The simulated XRD pattern of the cage-like trinuclear pyrazolium copper-containing energetic complex (Cu-MOF).

[0020] Figure 4 The measured XRD pattern of the cage-like trinuclear pyrazolium copper-containing energetic complex (Cu-MOF).

[0021] Figure 5This is a DSC diagram of a cage-like trinuclear pyrazolium copper(II) energetic complex (Cu-MOF). Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] Example 1

[0024] At room temperature, 3 mmol (339 mg) of 3-nitropyrazole was dispersed in a 50 mL polytetrafluoroethylene liner containing 2 mL of water, 2 mL of methanol, and 2 mL of LDMF (N,N-dimethylformamide) mixed solvent. Then, 3 mmol (723 mg) of copper nitrate trihydrate was added in a single batch. After sonication for 10 minutes, the mixture was transferred to a muffle furnace and reacted at 100 °C for 12 hours, followed by slow recovery to room temperature. Centrifugation was performed to remove the supernatant, yielding deep yellow crystals, i.e., Cu-MOF (yield: 85%), with the following crystal structure: Figure 1 As shown in the photos, the actual product is as follows. Figure 2 As shown.

[0025] The crystallographic data of the cage-like trinuclear pyrazolium copper(II) energetic complex (Cu-MOF) are shown in Table 1.

[0026] Table 1. Crystallographic data of cage-like trinuclear pyrazolium copper(II)

[0027]

[0028] In Example 2, at room temperature, 3 mmol (339 mg) of 3-nitropyrazole was dispersed in a 50 mL polytetrafluoroethylene liner containing 2 mL of water and 2 mL of methanol solvent. Then, 3 mmol (723 mg) of copper nitrate trihydrate was added at once. After sonication for 10 minutes, the mixture was transferred to a muffle furnace and reacted at 100°C for 12 hours. Afterward, it was allowed to slowly return to room temperature. After centrifugation, the supernatant was removed, and no deep yellow crystals were obtained.

[0029] Example 3

[0030] At room temperature, 3 mmol (339 mg) of 3-nitropyrazole was dispersed in a 50 mL polytetrafluoroethylene liner containing 2 mL of water and 2 mL of DMF (N,N-dimethylformamide) mixed solvent. Then, 3 mmol (723 mg) of copper nitrate trihydrate was added in a single batch. After sonication for 10 minutes, the mixture was transferred to a muffle furnace and reacted at 100 °C for 12 hours, followed by slow recovery to room temperature. Centrifugation was performed to remove the supernatant, yielding deep yellow crystals, i.e., Cu-MOF (yield: 65%).

[0031] Example 4

[0032] At room temperature, 3 mmol (339 mg) of 3-nitropyrazole was dispersed in a 50 mL polytetrafluoroethylene liner containing 2 mL of water, 2 mL of methanol, and 2 mL of LDMF (N,N-dimethylformamide) solvent. Then, 3 mmol (723 mg) of copper nitrate trihydrate was added in a single batch. After sonication for 10 minutes, the mixture was transferred to a muffle furnace and reacted at 90 °C for 12 hours, followed by a slow return to room temperature. Centrifugation was performed to remove the supernatant, yielding deep yellow crystals, i.e., Cu-MOF (yield: 75%).

[0033] The analytical results of the target product, a yellow solid, are as follows:

[0034] Actual XRD measurements Figure 3 As shown: 1 XRD (2θ): 7.89, 9.46°, 10.11°.

[0035] Simulated XRD, such as Figure 4 As shown: XRD(2θ): 7.82, 9.45, 10.15.

[0036] Thermal stability curve as shown Figure 5 As shown: DSC (356℃, 40℃-400℃, 20℃·min) -1 ).

[0037] The physical and chemical test results are as follows:

[0038] Density (g / cm³) 3 ): 2.262 g / cm³ 3 Detonation velocity (m / s): 6100m / s; Detonation pressure (Gpa): 16.96 (Gpa); Impact sensitivity: greater than 40J; Friction sensitivity: greater than 360N.

[0039] Although the invention has been described herein with reference to illustrative embodiments, the above embodiments are merely preferred embodiments of the invention, and the implementation methods of the invention are not limited to the above embodiments. It should be understood that those skilled in the art can devise many other modifications and implementations, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A cage-like trinuclear pyrazolium copper complex with ultra-high thermal stability, characterized in that, It has the following structure:

2. The cage-like trinuclear pyrazole copper(II) energetic complex as described in claim 1, characterized in that, Its unit cell parameters are: α = 92.716(4)°, β = 97.813(3)°, γ = 105.297(3)°, Z = 2, cell volume 3. A method for synthesizing the cage-like trinuclear pyrazolium copper energetic complex as described in claim 1 or 2, characterized in that, include: The step involves mixing 3-nitropyrazole with copper nitrate and then self-assembling to synthesize a cage-like trinuclear pyrazole cuprous energetic complex.

4. The method as described in claim 3, characterized in that, Specifically, the following steps are included: At a certain temperature, 3-nitropyrazole is dispersed in a reaction solvent, copper nitrate trihydrate is added, and after sonication, the mixture is reacted in a reaction vessel at a certain temperature. After natural cooling, it is centrifuged, filtered, washed, and dried to obtain a cage-like trinuclear pyrazole copper(II) energetic complex.

5. The method as described in claim 3 or 4, characterized in that, The reaction temperature is 90℃~100℃.

6. The method as described in claim 3 or 4, characterized in that, The reaction solvent is a mixture of water, methanol and N,N-dimethylformamide in a volume ratio of 1:1:

1.

7. The method as described in claim 3 or 4, characterized in that, The reaction time can be 10-14 hours.

8. Use of the cage-like trinuclear pyrazole copper energized complex as described in claim 1 or 2 as an initiating explosive.

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