Preparation method of olefin monomer of benzocrown ether imidazole polymerized ionic liquid

Abstract

The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of an olefin monomer of benzocrown ether imidazole polymerized ionic liquid. Comprising the following steps: adding benzo-12-crown-4-ether, iodo-alkyl acid and polyphosphoric acid into a heat preservation kettle, carrying out heating reaction, adding chloro-alkyl acid, carrying out heating reaction, dropwise adding water to hydrolyze residual polyphosphoric acid, extracting an organic phase by chloroform, washing chloro-alkyl acid by using a sodium carbonate aqueous solution, drying, carrying out suction filtration, and transferring into a reaction kettle; adding 1-methylimidazole, carrying out heating reaction, carrying out rotary evaporation to obtain chloroform, adding dioxane, triethylamine and hydroquinone, carrying out heating reaction, and carrying out rotary evaporation to obtain dioxane; the ionic liquid, organic salt and pure water are added into a dissolving kettle, dichloromethane is used for extracting an organic phase, pure water is used for washing chloride ions and iodide ions in the organic phase, dichloromethane is obtained through rotary evaporation, and a product is dried in vacuum. According to the method, the steps of acylation, quaternization and dehydrohalogenation are used, so that the steps are simplified, and the purification treatment process of acylation after quaternization is avoided.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, and specifically relates to a method for preparing olefin monomers of benzocrown ether imidazole polymeric ionic liquids. Background Technology

[0002] Crown ethers, with their unique cavity structure, can selectively complex and coordinate with various metal ions, and have wide applications in ion recognition, phase transfer catalysis, and isotope separation. 12-crown-4 ether and its derivatives, in particular, exhibit a unique role in stabilizing lithium ions in new energy batteries due to their effective complexation and coordination of lithium ions. Furthermore, they can be formulated into ionic liquids and used in conjunction with lithium sulfide in the preparation of solid-state electrolytes and lithium-sulfur batteries.

[0003] The aforementioned ionic liquids typically achieve their effects using crown ether imidazole ionic liquids and their derivatives, such as benzocrown ether imidazole ionic liquids and azacrown ether imidazole ionic liquids. Patent CN110396082A discloses a method for preparing 1-carboxy-3-methylimidazolium bromide from 1-methylimidazolium and bromoalkyl acids, followed by reaction with azacrown ethers to obtain 1-alkanoyl azacrown ether-3-methylimidazolium bromide, and then, through anion exchange, obtaining 1-alkanoyl azacrown ether-3-methylimidazolium bis(trifluoromethanesulfonate) imine salt / hexafluorophosphate ionic liquid. Patent CN110372678A discloses a method for reacting benzo[a]crown ether and bromoalkyl acid with polyphosphoric acid in a benzene ring carbonylation reaction, followed by a quaternization reaction with 1-methylimidazolium, purification, and anion exchange with lithium / sodium / potassium bis(trifluoromethanesulfonyl)imide (lithium / sodium / potassium hexafluorophosphate) to obtain a 1-alkanoylbenzo[a]crown ether-3-methylimidazolium bis(trifluoromethanesulfonyl)imide / hexafluorophosphate ionic liquid.

[0004] The ionic liquids prepared by the above-mentioned methods have a moderate melting point range of about 50~100℃, while the melting point of the ionic liquids required for solid electrolytes is 100~200℃. Therefore, although the above-mentioned ionic liquids can stabilize lithium ions through complexation coordination, they cannot meet the high melting point requirements of solid electrolytes. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides a method for preparing olefin monomers of benzocrown ether imidazole polymeric ionic liquids, thereby preparing monomers capable of low-degree polymerization, increasing the melting point of the ionic liquid, and simultaneously stabilizing the complexation and coordination with lithium ions.

[0006] This invention is achieved through the following technical solution: A method for preparing olefin monomers for benzocrown ether imidazole polymeric ionic liquids, wherein the molecular formula of the olefin monomer is: , Where n takes values ​​from 1 to 2, m takes values ​​from 2 to 4, and X - It is an acid radical anion. Includes the following steps: (1) Add a certain amount of benzo-12-crown 4-ether, iodoalkyl acid and polyphosphoric acid to a thermostatic reactor, heat to 65~75℃, turn on the stir, seal and keep warm for 8~10h, continue to add a certain amount of chloroalkyl acid, heat to 85~95℃, seal and keep warm for 10~12h, cool in an ice bath, add pure water dropwise to hydrolyze the remaining polyphosphoric acid, use a certain amount of chloroform to extract the organic phase 3~5 times, wash the chloroform extract 1~2 times with saturated sodium carbonate aqueous solution to remove the remaining chloroalkyl acid, add a certain amount of anhydrous sodium sulfate to dry and remove water, filter, and transfer the filtrate into the reaction vessel; (2) Add a certain amount of 1-methylimidazole to the reaction vessel, heat to 40~50℃, seal and stir for 20~24h, evaporate chloroform, add a certain amount of dioxane, triethylamine and hydroquinone, turn on the stirrer, heat and reflux for 12~16h, cool to room temperature, filter, filter the filtrate through activated carbon adsorption, evaporate dioxane to obtain the intermediate product benzocrown ether imidazole iodide ionic liquid; (3) Add the above benzocrown ether imidazole iodide ionic liquid, a quantitative amount of organic salt and pure water to a dissolving vessel, and carry out an ion exchange reaction for 14-18 h under stirring at 40-50℃. Extract the organic phase 3-5 times with a quantitative amount of dichloromethane. Wash the extract 3-5 times with a quantitative amount of pure water to remove chloride and iodide ions from the organic phase. Rotary distillation of dichloromethane and vacuum drying to obtain the target product.

[0007] According to the method for preparing olefin monomers of a benzocrown ether imidazole polymeric ionic liquid, the molar ratio of benzo-12-crown 4-ether, iodoalkyl acid and chloroalkyl acid in step (1) is 1:1:(1.1~1.3).

[0008] According to the method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid, in step (1) X - The anion is any one of tetrafluoroborate, acetate, or hexafluorophosphate anions.

[0009] According to the method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid, in step (1), the amount of polyphosphoric acid used is 15 to 20 times the mass of the benzo-12-crown 4-ether, the amount of pure water used for hydrolysis is 1 to 1.5 times the mass of the polyphosphoric acid, the mass of chloroform used in each extraction is 0.3 to 0.4 times the mass of the polyphosphoric acid, the mass of saturated sodium carbonate aqueous solution used in each washing is 0.1 to 0.2 times the mass of the polyphosphoric acid, and the amount of anhydrous sodium sulfate used is 0.05 to 0.1 times the total mass of chloroform used for extraction.

[0010] According to the method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid, in step (2), the amount of 1-methylimidazol is 1 times the molar amount of benzo-12-crown 4-ether, the amount of triethylamine is 1.3 to 1.5 times the molar amount of benzo-12-crown 4-ether, and the amount of hydroquinone is 0.01 to 0.03 times the molar amount of benzo-12-crown 4-ether.

[0011] According to the method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid, in step (2), the amount of dioxane used is 15 to 20 times the mass of 1-methylimidazolium, and the amount of activated carbon used is 0.03 to 0.05 times the mass of dioxane.

[0012] According to the method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid, in step (3), the organic salt is any one of sodium or potassium salts of tetrafluoroborate, acetate, or hexafluorophosphate, and the amount used is 1.1 to 1.2 times the molar amount of benzo-12-crown 4-ether; the amount of pure water used as solvent is 15 to 20 times the mass of benzo-12-crown 4-ether; the amount of dichloromethane used in each extraction is 0.2 to 0.3 times the mass of pure water used as solvent; and the amount of pure water used in each washing is 0.1 to 0.2 times the mass of pure water used as solvent.

[0013] Beneficial effects of this invention: The present invention provides a method for preparing olefin monomers of benzocrown ether imidazole polymeric ionic liquids. First, two different haloamino acids are acylated with benzo-12-crown 4-ether. By controlling the reaction conditions, 1-methylimidazolium is selectively quaternized to form a monoquaternary ammonium salt, and the remaining haloalkyl group is dehalogenated to form an olefin. This method uses acylation, quaternization, and dehydrohalogenation instead of the steps of acylation, quaternization, acylation, and dehydrohalogenation in the synthesis process. This not only simplifies the steps but also avoids the necessary purification process required for quaternization followed by acylation, further simplifying the process and reducing time and cost. Detailed Implementation

[0014] The specific details of this invention will be further explained below: This invention discloses a method for preparing olefin monomers of benzo[a]crown ether imidazole polymeric ionic liquids, wherein the molecular formula of the olefin monomer is […]. , Where n takes values ​​from 1 to 2, m takes values ​​from 2 to 4, and X - The anions are tetrafluoroborate, acetate, or hexafluorophosphate.

[0015] The specific preparation steps are as follows: (1) Add a certain amount of benzo-12-crown 4-ether, iodoalkyl acid and polyphosphoric acid to a thermostatic reactor, heat to 65~75℃, turn on the stir, seal and keep warm for 8~10h, continue to add a certain amount of chloroalkyl acid, heat to 85~95℃, seal and keep warm for 10~12h, cool in an ice bath, add pure water dropwise to hydrolyze the remaining polyphosphoric acid, use a certain amount of chloroform to extract the organic phase 3~5 times, wash the chloroform extract 1~2 times with saturated sodium carbonate aqueous solution to remove the remaining chloroalkyl acid, add a certain amount of anhydrous sodium sulfate to dry and remove water, filter, and transfer the filtrate into the reaction vessel; The molar ratio of benzo-12-crown 4-ether, iodoalkyl acid, and chloroalkyl acid is 1:1:(1.1~1.3); the amount of polyphosphoric acid used is 15~20 times the mass of benzo-12-crown 4-ether; the amount of pure water used for hydrolysis is 1~1.5 times the mass of polyphosphoric acid; the mass of chloroform used in each extraction is 0.3~0.4 times the mass of polyphosphoric acid; the mass of saturated sodium carbonate aqueous solution used in each washing is 0.1~0.2 times the mass of polyphosphoric acid; and the amount of anhydrous sodium sulfate used is 0.05~0.1 times the total mass of chloroform used for extraction.

[0016] (2) Add a measured amount of 1-methylimidazole to the reaction vessel, heat to 40-50℃, seal and stir for 20-24 hours, evaporate chloroform, add a measured amount of dioxane, triethylamine and hydroquinone, start stirring, heat to reflux for 12-16 hours, cool to room temperature, filter, filter the filtrate through activated carbon adsorption, evaporate dioxane to obtain the intermediate product benzocrown ether imidazole iodide ionic liquid; wherein the amount of 1-methylimidazole is 1 times the molar amount of benzo-12-crown 4-ether, the amount of triethylamine is 1.3-1.5 times the molar amount of benzo-12-crown 4-ether, the amount of hydroquinone is 0.01-0.03 times the molar amount of benzo-12-crown 4-ether, the amount of dioxane is 15-20 times the mass of 1-methylimidazole, and the amount of activated carbon is 0.03-0.05 times the mass of dioxane.

[0017] (3) The above-mentioned benzocrown ether imidazole iodide ionic liquid, a quantitative amount of organic salt, and pure water are added to a dissolving vessel, and an ion exchange reaction is carried out at 40-50℃ with stirring for 14-18 hours. The organic phase is extracted with a quantitative amount of dichloromethane 3-5 times, and the extract is washed with a quantitative amount of pure water 3-5 times to remove chloride and iodide ions from the organic phase. The dichloromethane is evaporated by rotary evaporation, and the product is obtained by vacuum drying. The organic salt is any one of the sodium or potassium salts of tetrafluoroborate, acetate, or hexafluorophosphate, and the amount used is 1.1-1.2 times the molar amount of the benzo-12-crown 4-ether; the amount of pure water used as solvent is 15-20 times the mass of the benzo-12-crown 4-ether; the amount of dichloromethane used in each extraction is 0.2-0.3 times the mass of the pure water used as solvent; and the amount of pure water used in each washing is 0.1-0.2 times the mass of the pure water used as solvent.

[0018] The reaction equations for the above process are as follows: , The following detailed description of the invention is difficult to provide with specific parameters and embodiments: Example 1

[0019] Step 1: Add 22.4g of benzo-12-crown 4-ether, 18.6g of iodoacetic acid, and 336g of polyphosphoric acid to a thermostatically insulated reactor. Start stirring and maintain the temperature at 70±5℃. Seal and keep the reactor at this temperature for 8 hours. Then add 15g of 5-chlorovaleric acid and maintain the temperature at 90±5℃. Continue to seal and keep the reactor at this temperature for 10 hours. Cool down to room temperature and add 336g of pure water dropwise under an ice bath to hydrolyze the remaining polyphosphoric acid. Then extract with 100g of chloroform each time. After 5 extractions, wash all the extracts with 33.6g of saturated sodium carbonate aqueous solution, then add 25g of anhydrous sodium sulfate to dry. After standing for 8 hours, filter and transfer the filtrate to the reactor.

[0020] Step 2: Add 8.2g of 1-methylimidazole to the reactor, start stirring, control the temperature at 45±5℃, seal and stir for 20h, evaporate chloroform under normal pressure, then add 123g of dioxane, 132g of triethylamine and 0.1g of hydroquinone in sequence, start stirring, heat to reflux for 12h, cool to room temperature, filter, add 3.7g of activated carbon to the filtrate and stir to adsorb for 4h, then filter, evaporate dioxane from the filtrate, the remaining solid is the intermediate product benzo[a]crown ether imidazole iodide ionic liquid.

[0021] Step 3: Transfer the above intermediate product into a dissolving vessel, add 12g sodium tetrafluoroborate and 336g pure water, start stirring, and carry out ion exchange reaction at 45±5℃ for 14h. Use 67g dichloromethane for extraction each time. After extraction 5 times, wash all the extract with pure water 5 times, using 34g of pure water each time. After washing, dichloromethane is evaporated from the extract and dried under vacuum at 70℃ for 2h to obtain 36.8g of the target product 1-{3-[2-(4-enyl)pentanoyl]benzo-12-crown 4-ether} acylethyl-3-methylimidazolium tetrafluoroborate.

[0022] Testing revealed a product purity of 95.45% and a yield (based on crown ether) of 67.71% (theoretical yield 51.88%). Example 2

[0023] Step 1: Add 22.4g of benzo-12-crown 4-ether, 18.6g of iodoacetic acid, and 448g of polyphosphoric acid to a thermostatically insulated reactor. Start stirring and maintain the temperature at 70±5℃. Seal and maintain the temperature for 10h. Then add 17.8g of 5-chlorovaleric acid and maintain the temperature at 90±5℃. Continue to seal and maintain the temperature for 12h. Cool down to room temperature and add 672g of pure water dropwise under ice bath to hydrolyze the remaining polyphosphoric acid. Then extract with 180g of chloroform each time. After three extractions, wash all the extracts with 33.6g of saturated sodium carbonate aqueous solution, then add 54g of anhydrous sodium sulfate to dry. After standing for 8h, filter and transfer the filtrate to the reactor.

[0024] Step 2: Add 8.2g of 1-methylimidazole to the reactor, start stirring, control the temperature at 45±5℃, seal and stir for 24h, evaporate chloroform under normal pressure, then add 164g of dioxane, 152g of triethylamine and 0.3g of hydroquinone in sequence, start stirring, heat to reflux and react for 16h, cool to room temperature, filter, add 8.2g of activated carbon to the filtrate and stir to adsorb for 4h, then filter, evaporate dioxane from the filtrate, the remaining solid is the intermediate product benzo[a]crown ether imidazole iodide ionic liquid.

[0025] Step 3: Transfer the above intermediate product into a dissolving vessel, add 13.2g of sodium tetrafluoroborate and 448g of pure water, start stirring, and carry out the ion exchange reaction at 45±5℃ for 18h. Use 134g of dichloromethane for extraction each time. After extraction 3 times, wash all the extract with pure water 3 times, using 90g of pure water each time. After washing, dichloromethane is evaporated from the extract by rotary evaporation. After vacuum drying at 70℃ for 2h, the target product 1-{3-[2-(4-enyl)pentanoyl]benzo-12-crown 4-ether} acylethyl-3-methylimidazolium tetrafluoroborate 34.7g is obtained.

[0026] Testing revealed a product purity of 96.17% and a yield (based on crown ether) of 64.32% (theoretical yield 51.88%). Example 3

[0027] Step 1: Add 22.4g of benzo-12-crown 4-ether, 20g of 3-iodopropionic acid iodoacetic acid, and 336g of polyphosphoric acid to a thermostatically insulated reactor. Start stirring and maintain the temperature at 70±5℃. Seal and keep the reactor at this temperature for 8 hours. Then add 16.6g of 6-chlorohexanoic acid and maintain the temperature at 90±5℃. Continue to seal and keep the reactor at this temperature for 10 hours. Cool down to room temperature and add 336g of pure water dropwise under an ice bath to hydrolyze the remaining polyphosphoric acid. Then extract with 100g of chloroform each time. After 5 extractions, wash all the extracts with 33.6g of saturated sodium carbonate aqueous solution, then add 25g of anhydrous sodium sulfate to dry. After standing for 8 hours, filter and transfer the filtrate to the reactor.

[0028] Step 2: Add 8.2g of 1-methylimidazole to the reactor, start stirring, control the temperature at 45±5℃, seal and stir for 20h, evaporate chloroform under normal pressure, then add 123g of dioxane, 132g of triethylamine and 0.1g of hydroquinone in sequence, start stirring, heat to reflux for 12h, cool to room temperature, filter, add 3.7g of activated carbon to the filtrate and stir to adsorb for 4h, then filter, evaporate dioxane from the filtrate, the remaining solid is the intermediate product benzo[a]crown ether imidazole iodide ionic liquid.

[0029] Step 3: Transfer the above intermediate product into a dissolving vessel, add 20.3g of potassium hexafluoroborate and 336g of pure water, start stirring, and carry out ion exchange reaction at 45±5℃ for 14h. Use 67g of dichloromethane for extraction each time. After extraction 5 times, wash all the extract with pure water 5 times, using 34g of pure water each time. After washing, dichloromethane is evaporated from the extract by rotary evaporation. After vacuum drying at 70℃ for 2h, the target product 1-{3-[2-(5-enyl)hexanoyl]benzo-12-crown 4-ether}acylpropyl-3-methylimidazolium tetrafluoroborate 40.1g is obtained.

[0030] Testing revealed a product purity of 95.71% and a yield (based on crown ether) of 63.44% (theoretical yield 60.5%). Example 4

[0031] Step 1: Add 22.4g of benzo-12-crown 4-ether, 20g of 3-iodopropionic acid and 448g of polyphosphoric acid to a thermostatically insulated reaction vessel, start stirring, control the temperature to 70±5℃, and keep the vessel sealed for 10h. Then add 19.6g of 6-chlorohexanoic acid, control the temperature to 90±5℃, and continue to keep the vessel sealed for 12h. Cool down to room temperature, add 672g of pure water dropwise under ice bath to hydrolyze the remaining polyphosphoric acid, and then extract with 180g of chloroform each time. After three extractions, wash all the extract with 33.6g of saturated sodium carbonate aqueous solution, then add 54g of anhydrous sodium sulfate to dry, let stand for 8h and filter, and transfer the filtrate to the reaction vessel.

[0032] Step 2: Add 8.2g of 1-methylimidazole to the reactor, start stirring, control the temperature at 45±5℃, seal and stir for 24h, evaporate chloroform under normal pressure, then add 164g of dioxane, 152g of triethylamine and 0.3g of hydroquinone in sequence, start stirring, heat to reflux and react for 16h, cool to room temperature, filter, add 8.2g of activated carbon to the filtrate and stir to adsorb for 4h, then filter, evaporate dioxane from the filtrate, the remaining solid is the intermediate product benzo[a]crown ether imidazole iodide ionic liquid.

[0033] Step 3: Transfer the above intermediate product into a dissolving vessel, add 22g of potassium hexafluoroborate and 448g of pure water, start stirring, and carry out ion exchange reaction at 45±5℃ for 18h. Use 134g of dichloromethane for extraction each time. After extraction 3 times, wash all the extract with pure water 3 times, using 90g of pure water each time. After washing, dichloromethane is evaporated from the extract and dried under vacuum at 70℃ for 2h to obtain 41.2g of the target product 1-{3-[2-(5-enyl)hexanoyl]benzo-12-crown 4-ether}acylpropyl-3-methylimidazolium tetrafluoroborate.

[0034] Testing revealed a product purity of 95.92% and a yield (based on crown ether) of 65.32% (theoretical yield 60.5%). This invention proposes an acylation reaction using two different haloamino acids with benzo-12-crown 4-ether. By controlling the reaction conditions, 1-methylimidazolium is selectively quaternized to form a monoquaternary ammonium salt, and the remaining haloalkyl group is dehalogenated to form an alkene. This method uses acylation, quaternization, and dehydrohalogenation instead of the steps of acylation, quaternization, acylation, and dehydrohalogenation in the synthesis process. This not only simplifies the steps but also avoids the necessary purification process required for quaternization followed by acylation, further simplifying the process and reducing time and cost.

[0035] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing an olefin monomer of a benzo[a]crown ether imidazole polymeric ionic liquid, characterized in that the olefin... The molecular formula of the monomer is , Where n takes values ​​from 1 to 2, m takes values ​​from 2 to 4, and X - It is an acid radical anion. Includes the following steps: (1) Add a certain amount of benzo-12-crown 4-ether, iodoalkyl acid and polyphosphoric acid to a thermostatic reactor, heat to 65~75℃, turn on the stir, seal and keep warm for 8~10h, continue to add a certain amount of chloroalkyl acid, heat to 85~95℃, seal and keep warm for 10~12h, cool in an ice bath, add pure water dropwise to hydrolyze the remaining polyphosphoric acid, use a certain amount of chloroform to extract the organic phase 3~5 times, wash the chloroform extract 1~2 times with saturated sodium carbonate aqueous solution to remove the remaining chloroalkyl acid, add a certain amount of anhydrous sodium sulfate to dry and remove water, filter, and transfer the filtrate into the reaction vessel; (2) Add a certain amount of 1-methylimidazole to the reaction vessel, heat to 40~50℃, seal and stir for 20~24h, evaporate chloroform, add a certain amount of dioxane, triethylamine and hydroquinone, turn on the stirrer, heat and reflux for 12~16h, cool to room temperature, filter, filter the filtrate through activated carbon adsorption, evaporate dioxane to obtain the intermediate product benzocrown ether imidazole iodide ionic liquid; (3) Add the above benzocrown ether imidazole iodide ionic liquid, a quantitative amount of organic salt and pure water to a dissolving vessel, and carry out an ion exchange reaction for 14-18 h under stirring at 40-50℃. Extract the organic phase 3-5 times with a quantitative amount of dichloromethane. Wash the extract 3-5 times with a quantitative amount of pure water to remove chloride and iodide ions from the organic phase. Rotary distillation of dichloromethane and vacuum drying to obtain the target product.

2. The method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid according to claim 1, characterized in that, The molar ratio of benzo-12-crown 4-ether, iodoalkyl acid and chloroalkyl acid in step (1) is 1:1:(1.1~1.3).

3. The method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid according to claim 1, characterized in that, In step (1), X - The anion is any one of tetrafluoroborate, acetate, or hexafluorophosphate anions.

4. The method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid according to claim 1, characterized in that, In step (1), the amount of polyphosphoric acid used is 15 to 20 times the mass of benzo-12-crown 4-ether, the amount of pure water used for hydrolysis is 1 to 1.5 times the mass of polyphosphoric acid, the mass of chloroform used in each extraction is 0.3 to 0.4 times the mass of polyphosphoric acid, the mass of saturated sodium carbonate aqueous solution used in each washing is 0.1 to 0.2 times the mass of polyphosphoric acid, and the amount of anhydrous sodium sulfate used is 0.05 to 0.1 times the total mass of chloroform used for extraction.

5. The method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid according to claim 1, characterized in that, In step (2), the amount of 1-methylimidazole used is 1 times the molar amount of benzo-12-crown 4-ether, the amount of triethylamine used is 1.3 to 1.5 times the molar amount of benzo-12-crown 4-ether, and the amount of hydroquinone used is 0.01 to 0.03 times the molar amount of benzo-12-crown 4-ether.

6. A method for preparing an olefin monomer for a benzocrown ether imidazole polymeric ionic liquid according to claim 1 or 5, characterized in that, In step (2), the amount of dioxane used is 15 to 20 times the mass of 1-methylimidazole, and the amount of activated carbon used is 0.03 to 0.05 times the mass of dioxane.

7. The method for preparing an olefin monomer of a benzocrown ether imidazole polymeric ionic liquid according to claim 3, characterized in that, The organic salt mentioned in step (3) is any one of the sodium or potassium salts of tetrafluoroborate, acetate, or hexafluorophosphate, and the amount used is 1.1 to 1.2 times the molar amount of benzo-12-crown 4-ether; the amount of the solvent pure water is 15 to 20 times the mass of benzo-12-crown 4-ether; the amount of dichloromethane used in each extraction is 0.2 to 0.3 times the mass of the solvent pure water; and the amount of pure water used in each washing is 0.1 to 0.2 times the mass of the solvent pure water.

Images