1-vinyl imidazole transition metal complex as well as preparation method and application thereof

Abstract

The invention discloses a 1-vinyl imidazole transition metal complex as well as a preparation method and application thereof, and belongs to the technical field of transition metal complexes. The structural formula of the 1-vinyl imidazole transition metal complex disclosed by the invention is ML4Cl2, CuL4 (NO3) 2 or CuL4 (ClO4) 2; wherein M is a cation corresponding to Mn, Cu, Co and Ni; and L is 1-vinyl imidazole. The 1-vinyl imidazole transition metal complex provided by the invention takes halogen, nitrate radical and perchlorate radical as coordination anions respectively, and can be prepared by reacting a metal salt solution with 1-vinyl imidazole. The 1-vinyl imidazole transition metal complex prepared by the invention can be spontaneously combusted with a strong oxidant such as fuming nitric acid, is short in ignition delay time, and can be applied to a solid-liquid propellant as a spontaneous combustion fuel or applied to a solid propellant as a solid fuel.

Description

Technical Field

[0001] The invention belongs to the technical field of transition metal complexes, and specifically relates to a 1-vinylimidazole transition metal complex and a preparation method and application thereof. Background Art

[0002] Propellants are a class of chemical substances that can quickly produce a large amount of high-temperature gas when burned. They can be used to launch projectiles such as gun projectiles, rockets and missiles. Propellants include solid-liquid propellants, liquid propellants and solid propellants. Solid-liquid propellants are also called solid-liquid mixed propellants, which include fuel and oxidizer. Usually, the propellant composed of solid fuel and liquid oxidizer is called standard type; conversely, the propellant composed of liquid fuel and solid oxidizer is reverse type, called reverse solid-liquid propellant.

[0003] Hypergolic fuels can self-ignite when in contact with the oxidizer in the propellant, without the need for an additional ignition device. They are extremely safe in applications such as rockets, missiles, and satellites that require thousands of ignitions. Hydrazine and its derivatives are currently the main hypergolic fuels used, but their disadvantages are high toxicity and volatility. However, among standard solid and liquid propellants, there are currently relatively few self-igniting solid fuels. Developing new self-igniting solid fuels is an important way to improve the combustion performance of hypergolic propellants.

[0004] Solid propellant is an energetic system composed of an oxidizer, a combustion agent and functional materials. With the development of science and technology, the requirements for the combustion performance of solid propellants are also constantly increasing. Combustion performance is the core of solid propellant technology, and plays a decisive role in the shooting accuracy and range of rocket weapons and the reliability of engine operation. Adding a combustion catalyst to solid propellant can increase the burning rate of the propellant, which is an important way to improve the combustion performance of solid propellant. The development of catalysts that can further improve the combustion performance of solid propellants is a topic that has been explored in this field. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and to provide a 1-vinylimidazole transition metal complex and a preparation method and application thereof. The prepared 1-vinylimidazole transition metal complex can spontaneously ignite with a strong oxidant such as fuming nitric acid, has a short ignition delay time, and can be used as a spontaneous combustion fuel in solid-liquid propellants or as a solid fuel in solid propellants.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows: The invention provides a 1-vinylimidazole transition metal complex, the structural formula of which is ML4Cl2, CuL4(NO3)2 or CuL4(ClO4)2; wherein M is a cation corresponding to Mn, Cu, Co or Ni; and L is 1-vinylimidazole.

[0007] Furthermore, the ML4Cl2 and CuL4(NO3)2 belong to the monoclinic crystal system and the P21 / n space group, and the CuL4(ClO4)2 belongs to the triclinc crystal system and the p-1 space group.

[0008] The present invention also provides a method for preparing the 1-vinylimidazole transition metal complex, comprising the following steps: The metal salt solution and 1-vinylimidazole are mixed and reacted at 60-80°C for 2-3 hours to obtain a reaction solution; the reaction solution is post-treated to obtain a precipitated product, which is washed and dried to obtain the 1-vinylimidazole transition metal complex; The solvent of the metal salt solution is water, and the molar ratio of metal ions to 1-vinyl imidazole in the metal salt solution is 1:4.

[0009] Furthermore, the metal salt is hydrochloride, nitrate or perchlorate.

[0010] Furthermore, the metal salt solution is one of a manganese chloride solution, a cobalt chloride solution, a nickel chloride solution, a cupric chloride solution, a cupric nitrate solution or a cupric perchlorate solution.

[0011] Furthermore, the mixing of the metal salt solution and 1-vinylimidazole is specifically: adding 1-vinylimidazole dropwise into the metal salt solution at a certain temperature.

[0012] Furthermore, the post-treatment of the reaction liquid is specifically: cooling the reaction liquid to room temperature and filtering; the washing is: washing with anhydrous ethanol.

[0013] The present invention also provides the use of the 1-vinylimidazole transition metal complex as a self-igniting fuel in a solid propellant.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) The present invention provides a 1-vinylimidazole transition metal complex, wherein the addition of an imidazole ligand in the complex enables the coordination polymer to stably burn, have a high heat of combustion, and provide high energy; the metal cation in the complex has a potential catalytic effect on solid propellants; (2) The present invention provides a method for preparing a 1-vinylimidazole transition metal complex. The raw materials used in the method are easily available, the reaction steps are simple and easy to operate, the conditions are mild, the risk factor is low, it is conducive to industrial production, and the environmental pollution is small, thereby making the application of the complex green and environmentally friendly; (3) The present invention provides an application of a 1-vinylimidazole transition metal complex, wherein the complex can spontaneously combust with a strong oxidant, such as fuming nitric acid, hydrogen peroxide, nitrogen tetroxide, etc., and can ignite without an ignition device, with a short ignition delay time; and the metal cations in the coordination polymer have a good catalytic effect on combustion, further improving the combustion performance of the propellant; the complex has a high nitrogen content, which can improve the combustion energy of the solid propellant, so the coordination polymer can be used as a self-igniting fuel in solid propellants. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the X-ray single crystal diffraction pattern of complex 1 prepared in Example 1; Figure 2 is the X-ray single crystal diffraction pattern of complex 2 prepared in Example 2; Figure 3 is the X-ray single crystal diffraction pattern of complex 3 prepared in Example 3; Figure 4 is the X-ray single crystal diffraction pattern of complex 4 prepared in Example 4; Figure 5 is the X-ray single crystal diffraction pattern of complex 5 prepared in Example 5; Figure 6 is the X-ray single crystal diffraction pattern of complex 6 prepared in Example 6; Figure 7 The results of the self-ignition delay time test of the complexes prepared in Examples 1 to 5 and fuming nitric acid. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below in conjunction with embodiments.

[0018] Those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If no specific techniques or conditions are specified in the examples, they are carried out according to the techniques or conditions described in the literature in this area or according to the product instructions. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased.

[0019] Example 1 A method for preparing tetrakis(1-vinylimidazole)manganese(II) chloride comprises the following steps: Dissolve 0.99 g (5 mmol) of manganese chloride tetrahydrate in 25 mL of deionized water to obtain a manganese chloride solution, place it in a round-bottom flask, and heat to 60 °C with stirring.

[0020] 1.88 g (20 mmol) of 1-vinyl imidazole was added dropwise to a 60 ℃ manganese chloride solution, and the mixture was reacted at 60 ℃ for 2 h to obtain a reaction solution, which was cooled to room temperature and filtered. The filtered solid was washed twice with anhydrous ethanol, and the washed precipitate was placed in a 60 ℃ oven and dried for 6 h to obtain complex 1.

[0021] In order to detect the crystal structure of the complex, the filtrate obtained by filtration is volatilized at room temperature to obtain a single crystal of the complex.

[0022] The single crystal of the complex was structurally detected by X-ray single crystal diffractometer. According to the detection results, the single crystal structure of the complex is MnL4Cl2, and L is 1-vinyl imidazole ligand.

[0023] Example 2 A method for preparing tetrakis(1-vinylimidazole)cobalt(II) chloride comprises the following steps: Dissolve 1.189 g (5 mmol) of cobalt chloride hexahydrate in 25 mL of deionized water to obtain a cobalt chloride solution, place it in a round-bottom flask, and heat to 60 °C with stirring.

[0024] 1.88 g (20 mmol) of 1-vinyl imidazole was added dropwise to a 60 ℃ cobalt chloride solution, and the mixture was reacted at 60 ℃ for 2 h to obtain a reaction solution, which was cooled to room temperature and filtered. The filtered solid was washed twice with anhydrous ethanol, and the washed precipitate was placed in a 60 ℃ oven and dried for 6 h to obtain complex 2.

[0025] In order to detect the crystal structure of the complex, the filtrate obtained by filtration is volatilized at room temperature to obtain a single crystal of the complex.

[0026] The single crystal of the complex was structurally detected by X-ray single crystal diffractometer. According to the detection results, the single crystal structure of the complex is CoL4Cl2, and L is 1-vinyl imidazole ligand.

[0027] Example 3 A method for preparing tetrakis(1-vinylimidazole)nickel(II) chloride comprises the following steps: Dissolve 1.19 g (5 mmol) nickel chloride hexahydrate in 25 mL deionized water to obtain a nickel chloride solution, place it in a round-bottom flask, and heat to 60 °C with stirring.

[0028] 1.88 g (20 mmol) of 1-vinyl imidazole was added dropwise to a 60 ℃ nickel chloride solution, and the mixture was reacted at 60 ℃ for 2 h to obtain a reaction solution, which was cooled to room temperature and filtered. The filtered solid was washed twice with anhydrous ethanol, and the washed precipitate was placed in a 60 ℃ oven and dried for 6 h to obtain complex 3.

[0029] In order to detect the crystal structure of the complex, the filtrate obtained by filtration is volatilized at room temperature to obtain a single crystal of the complex.

[0030] The single crystal of the complex was structurally detected by X-ray single crystal diffractometer. According to the detection results, the single crystal structure of the complex is NiL4Cl2, and L is 1-vinyl imidazole ligand.

[0031] Example 4 A method for preparing tetrakis(1-vinylimidazole)copper(II) chloride comprises the following steps: Dissolve 0.85 g (5 mmol) of cupric chloride dihydrate in 25 mL of deionized water to obtain a cupric chloride solution, place it in a round-bottom flask, heat it to 60 °C and stir.

[0032] 1.88 g (20 mmol) of 1-vinyl imidazole was added dropwise to a 60 ℃ copper chloride solution, and the mixture was reacted at 60 ℃ for 2 h to obtain a reaction solution, which was cooled to room temperature and filtered. The filtered solid was washed twice with anhydrous ethanol, and the washed precipitate was placed in a 60 ℃ oven and dried for 6 h to obtain complex 4.

[0033] In order to detect the crystal structure of the complex, the filtrate obtained by filtration is volatilized at room temperature to obtain a single crystal of the complex.

[0034] The single crystal of the complex was structurally detected by X-ray single crystal diffractometer. According to the detection results, the single crystal structure of the complex is CuL4Cl2, and L is 1-vinylimidazole ligand.

[0035] Example 5 A method for preparing tetrakis(1-vinylimidazole)copper(II) nitrate comprises the following steps: Dissolve 1.21 g (5 mmol) of copper nitrate trihydrate in 25 mL of deionized water to obtain a copper nitrate solution, place it in a round-bottom flask, heat it to 60 °C and stir.

[0036] 1.88 g (20 mmol) of 1-vinyl imidazole was added dropwise to a 60 ℃ copper nitrate solution, and the mixture was reacted at 60 ℃ for 2 h to obtain a reaction solution, which was cooled to room temperature and filtered. The filtered solid was washed twice with anhydrous ethanol, and the washed precipitate was placed in a 60 ℃ oven and dried for 6 h to obtain complex 5.

[0037] In order to detect the crystal structure of the complex, the filtrate obtained by filtration is volatilized at room temperature to obtain a single crystal of the complex.

[0038] The single crystal of the complex was structurally detected by X-ray single crystal diffractometer. According to the detection results, the molecular formula of the repeating unit of the single crystal of the complex is CuL4(NO3)2, and L is 1-vinyl imidazole ligand.

[0039] Example 6 A method for preparing tetrakis(1-vinylimidazole)cobalt(II) perchlorate, the method comprising the following steps: Dissolve 1.85 g (5 mmol) of copper perchlorate hexahydrate in 25 mL of deionized water to obtain a copper perchlorate solution, place it in a round-bottom flask, heat it to 60 °C and stir.

[0040] 1.88 g (20 mmol) of 1-vinyl imidazole was added dropwise to a 60 ℃ copper perchlorate solution, and the mixture was reacted at 60 ℃ for 2 h to obtain a reaction solution, which was cooled to room temperature and filtered. The filtered solid was washed twice with anhydrous ethanol, and the washed precipitate was placed in a 60 ℃ oven and dried for 6 h to obtain complex 6.

[0041] In order to detect the crystal structure of the complex, the filtrate obtained by filtration is volatilized at room temperature to obtain a single crystal of the complex.

[0042] The single crystal of the complex was structurally detected by X-ray single crystal diffractometer. According to the detection results, the molecular formula of the repeating unit of the single crystal of the complex is CuL4(ClO4)2, and L is 1-vinylimidazole ligand.

[0043] The structures of the complexes 1 to 6 obtained in the above examples 1 to 6 are shown in Table 1 below:

[0044] The complexes prepared in Examples 1 to 6 were tested as follows: The complex and fuming nitric acid were tested for the self-ignition delay time. The specific method was as follows: 1 g of the final product of Examples 1 to 6 was placed in a plastic tube, and 1 mL of fuming nitric acid was added dropwise at a distance of 3 cm above the surface of the final product in the plastic tube; before adding the fuming nitric acid, the ignition process was filmed with a high-speed camera with a frame rate of 1000, and the contact time between the fuming nitric acid and the sample was set to 0 ms. The test results are shown in Figure 7 It can be seen that the ignition delay time of 1-vinyl imidazole copper complex with fuming nitric acid is only 17 ms, which is short and has good self-ignition properties. Complex 6 cannot spontaneously ignite after contacting with oxidants.

[0045] The above embodiments describe the implementation methods of the present invention in detail, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The above description is only a preferred feasible embodiment of the present invention, and does not limit the scope of rights of the present invention. All equivalent structural changes made by using the contents of the present invention specification are included in the scope of rights of the present invention.

Claims

1. 1-vinylimidazole transition metal complex, characterized in that Its structural formula is ML4Cl2, CuL4(NO3)2 or CuL4(ClO4)2; wherein M is a cation corresponding to Mn, Cu, Co, or Ni; and L is 1-vinylimidazole.

2. The 1-vinylimidazole transition metal complex according to claim 1, characterized in that The ML4Cl2 and CuL4(NO3)2 belong to the monoclinic crystal system and the P21 / n space group, and the CuL4(ClO4)2 belongs to the triclinc crystal system and the p-1 space group.

3. The method for preparing the 1-vinylimidazole transition metal complex according to claim 1, characterized in that: The steps include: The metal salt solution and 1-vinylimidazole are mixed and reacted at 60-80°C for 2-3 hours to obtain a reaction solution; the reaction solution is post-treated to obtain a precipitated product, which is washed and dried to obtain the 1-vinylimidazole transition metal complex; The solvent of the metal salt solution is water, and the molar ratio of metal ions to 1-vinyl imidazole in the metal salt solution is 1:

4.

4. The method for preparing the 1-vinylimidazole transition metal complex according to claim 3, characterized in that: The metal salt is hydrochloride, nitrate or perchlorate.

5. The method for preparing the 1-vinylimidazole transition metal complex according to claim 4, characterized in that: The metal salt solution is one of a manganese chloride solution, a cobalt chloride solution, a nickel chloride solution, a cupric chloride solution, a cupric nitrate solution or a cupric perchlorate solution.

6. The method for preparing the 1-vinylimidazole transition metal complex according to claim 3, characterized in that: The mixing of the metal salt solution and 1-vinylimidazole is specifically: adding 1-vinylimidazole dropwise into the metal salt solution at a certain temperature.

7. The method for preparing the 1-vinylimidazole transition metal complex according to claim 3, characterized in that: The post-treatment of the reaction liquid specifically includes: cooling the reaction liquid to room temperature and filtering; the cleaning includes: cleaning with anhydrous ethanol.

8. Use of the 1-vinylimidazole transition metal complex according to claim 1 as a hypergolic fuel in solid propellants.

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