CN108329360B

CN108329360B - Ferrocene picrate ionic compound and preparation method thereof

Info

Publication number: CN108329360B
Application number: CN201810338709.0A
Authority: CN
Inventors: 张国防; 程文倩; 孙烈春; 刘漫漫; 姜丽萍; 张娜; 高子伟; 张伟强
Original assignee: Shaanxi Normal University
Current assignee: Shaanxi Normal University
Priority date: 2018-04-16
Filing date: 2018-04-16
Publication date: 2020-10-13
Anticipated expiration: 2038-04-16
Also published as: CN108329360A

Abstract

The invention discloses a kind of ferrocenyl picrate ionic compound and a preparation method thereof, wherein the structural formula of the ionic compound is as follows:

wherein R represents chlorine, 2,4, 6-trinitrophenol group or 2,4, 6-trinitroresorcinol group. The complex of the invention has simple preparation method, low cost and high yield, the ferrocenium picrate reduces the mobility and volatility of the ferrocene burning rate catalyst by introducing ferrocenium cations and picric acid radical anions and ionizing, and the picric acid radical anions and the cations also contain energetic groups, so the complex has higher generated heat and combustion heat, can improve the energy level of the solid propellant in the combustion process, and has better combustion catalysis effect on the main components of the composite solid propellant, such as ammonium perchlorate, hexogen and the like.

Description

Ferrocene picrate ionic compound and preparation method thereof

Technical Field

The invention belongs to the technical field of solid propellants, and particularly relates to an iron arylcene picrate ionic compound and a preparation method thereof.

Background

The hydroxyl-terminated polybutadiene (HTPB) composite solid propellant (a hydroxyl-terminated propellant for short) in the solid propellant is popular in the aerospace field at home and abroad due to excellent process performance, mechanical property and aging property, low price and low viscosity of a prepolymer body HTPB, and the composite solid propellant is suitable for high-solid-content formula charging and large-scale pouring process charging and becomes a propellant widely used in military strategy and tactical missile systems at home and abroad at present. Compared with other burning rate catalysts, the ferrocene compound has the advantages of better flammability, dispersibility, uniformity, compatibility and the like, becomes the most used burning rate catalyst of the existing composite propellant, particularly the AP/Al/HTPB hydroxyl butyl propellant, and is widely applied to various military medium and remote missile propulsion systems.

The ferrocene burning rate catalysts applied in the solid propellant so far mainly include n-butyl ferrocene, tert-butyl ferrocene, 2-bis (ethyl ferrocenyl) propane (Catocene), octyl ferrocene and bis-ethyl ferrocenyl methane (Hycat 6D). Although the commercial ferrocene burning rate catalysts can greatly improve the burning rate of propellants such as butylated hydroxytoluene and the like, the commercial ferrocene burning rate catalysts have the serious defects of easy migration, easy volatilization, low-temperature crystallization, no energy and the like in application, and researchers put forward a series of improvement schemes aiming at the problems.

A U.S. patent published in Huskins in 1972 proposed the introduction of allyl alcohol structure into ferrocene to produce mononuclear ferrocene containing bisallyl alcohol, the introduction of hydroxyl groups significantly reducing migration and volatility. In 1974, Huskens subsequently tried to introduce an isopropylcyano group into ferrocenylbutadiene, reduce the mobility and volatility by increasing the carbon chain and introducing an active group, cyanic acid, and obtain better catalytic activity. Bis- (methylferrocenyl) -methane, 2-bis- (methylferrocenyl) -propane and 2, 2-bis (methylferrocenyl) -butane were also synthesized by wu shong et al in 1989. Two high-efficiency burning rate catalysts, BBFPr (2, 2-bis- (butylferrocene) propane) and BBFPe (1, 1-bis- (butylferrocene) pentane), were synthesized by modifying Catocene in Brutode oil Co., Ltd., Germany in 1995. In 2001, 1, 4-bisferrocenyl imidazole is synthesized by Klimova and the like for the reference of the Yuanfeng and the like, so that three bisferrocene high-nitrogen derivatives are designed and prepared, and the stability and the burning rate catalysis effect of the synthesized compound are tested. Two series of compounds, 2-bis- (monoalkylferrocenyl) -propane and 2, 2-bis (alkylferrocenyl) -propane, were successfully synthesized by people on the verge of happiness in 2004. A novel ethylidene ferrocene derivative is prepared in a patent published in 2009 by Lizang and Tangxiaoming, and the product has the advantages of low synthesis cost, relatively simple preparation process and good catalytic action. In 2010, ferrocene alkynone compounds are modified and improved while occupying a topic group, ferrocene triazole derivatives are synthesized, and are combined with transition metals Cu and Zn in a coordination mode to prepare a series of ferrocene complexes, and the electrochemical performance and the combustion catalytic performance of the ferrocene complexes are researched. Then the subject group synthesizes a novel ferrocene burning-rate catalyst biferrocene unsaturated beta-diketone transition metal complex and a ferrocene aryl beta-diketone metal complex by introducing active groups with large polarity (ferrocene beta-diketone) and metal (Cu and Ni) in a coordination mode. In 2011, Zhang rock et al prepared an epoxidized hydroxyl-terminated polybutadiene ferrocenecarboxylic acid (EHTPB) burning rate catalyst by in-situ grafting ferrocenecarboxylic acid and high-performance adhesive epoxidized hydroxyl-terminated polybutadiene EHTPB. In 2014, Wangchun swallow takes ferrocene tetrazole as a main ligand, 2, 2-bipyridine and 1, 10-phenanthroline as auxiliary ligands, and forms a series of ferrocene tetrazole metal complexes with transition metals.

Disclosure of Invention

The invention aims to overcome the defects of easy migration, easy volatilization and no energy per se of the existing ferrocene catalyst, provide the ferrocenium picrate ionic compound which has good thermal stability under natural conditions, higher heat of formation and combustion and adjustable catalytic performance, and provide a preparation method which is simple to operate and has lower cost for the ionic compound.

The structural formula of the aromatic ferrocene picrate ionic compound adopted for solving the technical problems is as follows:

wherein R represents chlorine, 2,4, 6-trinitrophenol group or 2,4, 6-trinitroresorcinol group.

When R represents chlorine, the preparation method of the ferrocenyl picrate ionic compound comprises the following steps: uniformly mixing ferrocene, aluminum powder, anhydrous aluminum trichloride and chlorobenzene, refluxing for 3-4 hours at 120-140 ℃, adding methanol and ice water, filtering, separating filtrate to obtain a water phase, extracting the water phase with cyclohexane, adding a sodium picrate water solution into the extracted water phase under a dark condition, stirring at normal temperature for reacting for 20-30 minutes, filtering, and drying in vacuum to obtain a cyclopentadienyl iron picrate ionic compound, namely [ cyclopentadiene-iron-chlorobenzene ] picrate; wherein the molar ratio of the ferrocene, the aluminum powder, the anhydrous aluminum trichloride, the chlorobenzene and the sodium picrate is 1: 2.5-3.5: 1-1.5: 1.

When R represents 2,4, 6-trinitrophenol, the preparation method of the ferrocenium picrate ionic compound comprises the following steps: under the condition of keeping out of the sun, dissolving [ cyclopentadiene-iron-chlorobenzene ] picrate, picric acid and potassium carbonate in N, N-dimethylformamide according to the molar ratio of 1: 1-1.5: 2.5-3.5, reacting for 2-3 hours, adding ice water, filtering, washing with absolute ethyl alcohol, and drying in vacuum to obtain the aromatic cyclopentadienyl iron picrate ionic compound.

When R represents 2,4, 6-trinitroresorcinol group, the preparation method of the ferrocenium picrate ionic compound comprises the following steps: under the condition of keeping out of the sun, dissolving [ cyclopentadiene-iron-chlorobenzene ] picrate, trinitroresorcinol and potassium carbonate in N, N-dimethylformamide according to the molar ratio of 1: 1-1.5: 2.5-3.5, reacting for 2-3 hours, adding ice water, filtering, washing with absolute ethyl alcohol, and drying in vacuum to obtain the aromatic cyclopentadienyl iron picrate ionic compound.

The invention has the following advantages:

1. the ferrocenium in the ferrocenium picrate has a sandwich structure similar to ferrocene, and is mainly formed by complexing negatively charged cyclopentadiene negative ions and electrically neutral arene ligands with metallic iron to form stable cations with a positive charge, and then combining with anionic picric acid radicals. The ionic compound takes picric acid radicals as anions, has high nitrogen content, also takes the picric acid radicals and trinitroresorcinol ions of a cation aromatic ring part as nitrogen-rich energetic groups, has extremely low vapor pressure and volatility, has higher generated heat and combustion heat, and is beneficial to solving the problems of easy migration and easy volatilization of ferrocene combustion regulators in propellants.

2. The ionic compound can regulate and control the catalytic performance of ammonium perchlorate, hexogen and otto gold which are main components of the composite solid propellant, change the chemical reaction speed of the propellant during low-pressure combustion, reduce the sensitivity of the burning rate of the propellant influenced by temperature and pressure, improve the ignition performance of the propellant, improve the combustion stability of the propellant and regulate the burning rate of the propellant, thereby realizing different thrust schemes required by the design of the propellant.

3. The ionic compound of the invention has simple preparation method, lower cost and higher yield, and overcomes the defects of complicated synthesis process, high cost, long synthesis period and the like of the existing ferrocene burning-rate catalyst.

Drawings

FIG. 1 is a differential scanning calorimetry analysis of ammonium perchlorate with 5% of the compounds of examples 1 to 3 added thereto.

FIG. 2 is a differential scanning calorimetry analysis of hexogen with 5% of the compound of examples 1-3 added.

FIG. 3 is a differential scanning calorimetry analysis of Auktogin with 5% of the compound of examples 1-3 added.

Detailed Description

The invention will be further described in detail with reference to the following figures and examples, but the scope of the invention is not limited to these examples.

Example 1

Adding 0.93g (5.0mmol) of ferrocene, 0.405g (15.0mmol) of aluminum powder, 2g (15.0mmol) of anhydrous aluminum trichloride and 5mL of chlorobenzene into a 50mL round-bottom flask, magnetically stirring uniformly, heating the flask in an oil bath to 130 ℃, refluxing for 4 hours, transferring the flask into an ice water bath for full cooling, slowly injecting 2mL of methanol into the flask in batches through a condensation tube under the condition of continuous stirring, then pouring 20mL of ice water into the flask, removing the aluminum powder by reduced pressure filtration after the reaction liquid does not release heat any more and is fully cooled, separating the filtrate, extracting the separated water phase for 3 times (10 mL each time) by cyclohexane to obtain [ cyclopentadiene-iron-chlorobenzene ] aluminum tetrachloride salt, wherein the reaction equation is as follows:

dissolving 1.255g (5.0mmol) of sodium picrate in 2.5mL of distilled water, adding the extracted water phase in a dark place, wherein a large amount of light yellow solid can be separated out, continuously stirring in the dark place for 30 minutes, filtering under reduced pressure, and drying in a vacuum drying oven at 40 ℃ to obtain a light yellow powdery solid product [ cyclopentadiene-ferrum-chlorobenzene ] picrate, wherein the yield is 49.5%, and the reaction equation is as follows:

the above-mentioned [ cyclopentadiene-iron-chlorobenzene ]]The solubility of the picrate in water is very small, the picrate can be dissolved in acetonitrile, acetone and DMSO, and the structural characterization data is as follows:¹H NMR(400MHz,CDCl₃-d₆):8.55(s,2H),6.78(s,2H),6.42(s,2H),66.28(m,1H),5.19(s,5H)。

example 2

0.461g (1.0mmol) of [ cyclopentadiene-iron-chlorobenzene ] picrate, 0.287g (1.25mmol) of picric acid, 0.382g (2.77mmol) of potassium carbonate and 5mLN, N-dimethylformamide are added into a 10mL brown reaction flask, stirred at room temperature in a dark place for 2 hours, then 5mL of ice water is added into the reaction flask, at which time a large amount of dark yellow solid is separated out, and then the mixture is filtered under reduced pressure, and after being washed with absolute ethyl alcohol, the filter cake is dried in a vacuum drying oven at 40 ℃ to obtain a yellow flocculent solid product [ cyclopentadiene-iron-2, 4, 6-trinitrodiphenyl ether ] picrate, the yield of which is 82.4%, and the reaction equation is as follows:

the above-mentioned [ cyclopentadiene-Fe-2, 4, 6-trinitrodiphenyl ether ]]The solubility of the picrate in water is very small, the picrate can be dissolved in acetonitrile, acetone and DMSO, and the structural characterization data is as follows:¹H NMR(400MHz,CDCl₃-d₆):8.59(s,4H),6.83(s,2H),6.48(s,2H),6.35(s,1H),5.23(s,5H)。

example 3

Adding 0.461g (1.0mmol) of [ cyclopentadiene-iron-chlorobenzene ] picrate, 0.306g (1.25mmol) of trinitroresorcinol, 0.382g (2.77mmol) of potassium carbonate and 5mLN, N-dimethylformamide into a 10mL brown reaction flask, stirring at room temperature in the dark for 2 hours to ensure that a large amount of dark yellow solid is separated out, then adding 5mL of ice water into the reaction flask, standing, filtering under reduced pressure, washing a filter cake with a small amount of absolute ethyl alcohol, and drying in a vacuum drying oven at 40 ℃ to obtain a yellow solid product [ cyclopentadiene-iron-2, 4, 6-trinitro-3-hydroxydiphenyl ether ] picrate, wherein the yield is 62.6%, and the reaction equation is as follows:

the above-mentioned [ cyclopentadiene-Fe-2, 4, 6-trinitro-3-hydroxydiphenyl ether ]]The solubility of the picrate in water is very small, the picrate can be dissolved in ethanol, acetonitrile, acetone and DMSO, and the structural characterization data is as follows:¹H NMR(400MHz,CDCl₃-d₆):8.59(s,1H),8.55(s,2H),6.74(s,2H),6.40(s,2H),6.29(s,1H),5.17(s,5H)。

in order to prove the beneficial effects of the invention, the inventors tested the catalytic performance of the ferrocenium picrate ionic compound prepared in examples 1-3, and the specific test is as follows:

(1) respectively taking 5mg of each compound prepared in the examples 1-3 and 95mg of powdery AP, and uniformly grinding and mixing;the catalytic performance of the catalyst was measured by a differential scanning calorimeter, and the results are shown in FIG. 1. As can be seen from fig. 1, the thermal decomposition of AP can be divided into three stages: the first process is the phase transition endothermic process of AP, the peak temperature is 237.9 ℃, the peak temperature of the second stage is 286.0 ℃, the process is the low-temperature decomposition process of AP, the peak temperature of the third stage is 404.6 ℃, the process is called the pyrolysis stage, the downward endothermic peak is shown from the low-temperature pyrolysis stage to the pyrolysis stage, and the gas (HCl, NH) formed by the thermal decomposition of AP at the stage is the endothermic peak₃) The absorbed heat is larger than the released heat by the decomposition of the AP, so the heat release of the AP by the thermal decomposition process is not obvious. After 5% of the compound of example 1-3 was added to AP, the crystal transition temperature of AP shifted backwards from 237.9 ℃ to about 10 ℃. Meanwhile, the pyrolysis stage of AP is shifted backwards from the original 286.0 ℃ by about 5 ℃. The most varied is that the original heat absorption peak of AP at the high-temperature decomposition stage disappears, namely the peak at 404.6 ℃ in the figure shows new heat release peaks at 358.4 ℃, 374.5 ℃ and 366.1 ℃, and the heat release peaks are advanced to a greater extent than the heat absorption peak at 404.6 ℃ of AP, and the heat release amount is up to 990.3-1092.2J/g, so that the compounds 1-3 can be analyzed to have obvious catalytic action on the thermal decomposition of AP. Therefore, compared with pure AP, the compound of the invention has the advantages that the high-temperature decomposition stage of the system shows a concentrated heat release phenomenon after the compound is added, the heat release peak temperature is advanced, and the released heat is obviously increased, which shows that the compound of the invention has good combustion catalysis effect on the thermal decomposition of AP.

(2) Respectively taking 5mg of each compound prepared in the examples 1-3 and 95mg of powdered hexogen (RDX), grinding and uniformly mixing; the catalytic performance of the catalyst was measured by a differential scanning calorimeter, and the results are shown in FIG. 2. As can be seen from figure 2, RDX has a remarkable exothermic decomposition peak at 229.2 ℃, and the heat released is 803.6J/g; when 5% of the compound of examples 1 to 3 was added to RDX, the heat release of RDX was increased, and the compound of example 1 maximized the heat release of RDX to 1278.3J/g. After the compounds of examples 1-3 were added, the peak temperature values of pure RDX at 230.0 ℃ were increased by 1.9 ℃, 2.8 ℃ and 2.3 ℃ respectively, but the heat release was changed from 803.6J/g to 1278.3J/g, 925.2J/g and 893.3J/g, respectively, which were all improved to some extent, and particularly, the increase was very significant after the compound of example 1 was added. It can be seen that the compounds of examples 1-3 play a certain catalytic role in RDX thermal decomposition in the aspect of heat release.

(3) Respectively taking 1mg of each compound prepared in the embodiments 1-3 and 99mg of powdered octogen (HMX), grinding and uniformly mixing; the catalytic performance of the catalyst was measured by a differential scanning calorimeter, and the results are shown in FIG. 3. It can be seen from the figure that, when 1% of the compounds of examples 1 to 3 was added to HMX under the same external conditions, the decomposition temperature of HMX was lowered although the amount of heat release did not change much before and after the addition. The addition of the compounds of examples 1 and 2 reduced the decomposition temperature by 0.2 ℃ and 2 ℃ respectively, while the addition of the compound of example 3 resulted in a partial decomposition of HMX at 241.8 ℃ and a reduction of the peak temperature by 5.1 ℃ when it was completely decomposed. The compounds of examples 1-3 are shown to have a certain catalytic effect on HMX at the thermal decomposition temperature.

From the above series of catalytic performance test experiments, it can be concluded that: the catalytic action of the compounds of the embodiments 1 to 3 on AP is most obvious, so that the peak temperature of thermal decomposition is more concentrated, and the heat release is also obviously increased; the compounds of examples 1 to 3 did not lower the peak temperature of RDX, but increased the amount of heat release of RDX to some extent; the compounds of examples 1-3 lead to a thermal decomposition temperature of HMX.

Claims

1. An iron arylcyclopentadienyl picrate ionic compound, which is characterized in that the structure of the ionic compound is as follows:

wherein R represents 2,4, 6-trinitrophenol group or 2,4, 6-trinitroresorcinol group.

2. A process for the preparation of an iron arylmetallocene picrate ionic compound of claim 1, wherein R represents a 2,4, 6-trinitrophenol group, characterized in that: under the condition of keeping out of the sun, dissolving [ cyclopentadiene-iron-chlorobenzene ] picrate, picric acid and potassium carbonate in N, N-dimethylformamide according to the molar ratio of 1: 1-1.5: 2.5-3.5, reacting for 2-3 hours, adding ice water, filtering, washing with absolute ethyl alcohol, and drying in vacuum to obtain the aromatic cyclopentadienyl iron picrate ionic compound.

3. A process for the preparation of an iron arylmetallocene picrate ionic compound of claim 1, wherein R represents 2,4, 6-trinitroresorcinol group, characterized in that: under the condition of keeping out of the sun, dissolving [ cyclopentadiene-iron-chlorobenzene ] picrate, trinitroresorcinol and potassium carbonate in N, N-dimethylformamide according to the molar ratio of 1: 1-1.5: 2.5-3.5, reacting for 2-3 hours, adding ice water, filtering, washing with absolute ethyl alcohol, and drying in vacuum to obtain the aromatic cyclopentadienyl iron picrate ionic compound.