MOFs (Metal-Organic Frameworks) catalyst for synthesizing diether fluorene as well as preparation method and application thereof
By using MOFs catalysts, the equipment corrosion and environmental protection problems caused by acidic catalysts in the prior art are solved, and the efficient and environmentally friendly synthesis of bis ether fluorene is achieved, and the colority and purity of the product meet the optical application requirements.
Patent Information
- Application Number
- CN202411165339.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-23
- Publication Date
- 2025-02-18
AI Technical Summary
In the existing bis ether fluorene synthesis technology, a large number of acidic catalysts used cause equipment corrosion and contamination, and the color and purity of the products cannot meet the requirements of optical use, and there are environmental protection problems.
Using MOFs catalyst, materials such as imidazole-2-formaldehyde, zinc nitrate hexahydrate and sodium bisulfite were reacted to form ZIF-90-SO3Na by preparation method, and further processing was obtained for bis ether fluorene synthesis. The catalyst has a porous structure, high acidic position density, good thermal stability, and can be recycled and used.
It has achieved efficient synthesis of bis ether fluorene, high catalytic efficiency, no easy corrosion of equipment, product chromaticity and purity meet the requirements of optical use, and excellent environmental protection performance. The catalyst can be recycled several times.
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of bisetherfluorene synthesis, and in particular to a MOFs catalyst for bisetherfluorene synthesis and a preparation method and application thereof. Background Art
[0002] In recent years, fluorene derivatives, especially bis(ether)fluorene (BPEF), have gradually become the raw materials for epoxy resins, polyesters, polyethers, polycarbonates and other materials due to their good heat resistance, transparency, high refractive index, etc.; they are mainly used in mid-to-high-end fields such as optical lenses, optical discs, films, engineering plastics, etc., and have good development prospects.
[0003] There are two synthetic routes for bisether fluorene: (1) Using 9-fluorenone and phenoxyethanol as starting materials, reacting in the presence of a strong acid catalyst and a thiol compound as an auxiliary agent to generate bisether fluorene, and then preparing high-purity bisether fluorene by recrystallization. Among them, the strong acid catalysts used are roughly divided into several categories such as concentrated inorganic acids, heteropoly acids, and strong acid cation exchange resins. Although this synthetic route has cheap raw materials, low cost, simple synthesis, and high yield; however, the large amount of acid catalyst used in the preparation process will cause irreversible corrosion to metal equipment and accelerate equipment aging; at the same time, the bisether fluorene obtained by this method has S residues, making it impossible to obtain the color or purity required for optical materials in subsequent material synthesis; in addition, this process will produce a large amount of three wastes, which is not in line with the concept of green development, and environmental post-treatment is more difficult.
[0004] (2) 9,9-bis(4-hydroxyphenyl)fluorene and ethylene oxide or 2-halogenated alcohol or ethylene glycol carbonate are used as starting materials, and react in the presence of an alkaline catalyst such as sodium hydroxide, potassium hydroxide, sodium ethoxide, triethylamine, imidazole, pyridine, etc. to generate the target product, diether fluorene. Although this synthetic route is simple, has a high yield, and generates little waste, its raw material 9,9-bis(4-hydroxyphenyl)fluorene is complicated and expensive to prepare, so the cost is high, the economic benefits cannot be satisfied, and it has now been gradually eliminated.
[0005] In view of this, the present invention is proposed. Summary of the invention
[0006] The purpose of the present invention is to provide a MOFs catalyst for the synthesis of bisetherfluorene, a preparation method and an application thereof. The MOFs catalyst of the present invention can better catalyze the synthesis of bisetherfluorene, and has high catalytic efficiency, good thermal stability and small dosage; in addition, the MOFs catalyst has the advantages of being porous, recyclable and not prone to corrosion of containers.
[0007] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:
[0008] The first aspect of the present invention provides a method for preparing a MOFs catalyst for the synthesis of bisetherfluorene, the preparation method comprising the following steps:
[0009] (a) dissolving imidazole-2-carboxaldehyde and triethylamine in methanol to obtain solution A; dissolving zinc nitrate hexahydrate in methanol to obtain solution B; mixing solution A and solution B and heating them under reflux for reaction, cooling, washing and drying after the reaction is completed to obtain white powder ZIF-90;
[0010] (b) dissolving ZIF-90 in methanol, adding sodium bisulfite solution and heating under reflux reaction, cooling, washing and drying after the reaction is completed to obtain white powder ZIF-90-SO3Na;
[0011] (c) placing ZIF-90-SO3Na in an acid solution for a period of time, washing, and drying to obtain the MOFs catalyst for the synthesis of bisetherfluorene.
[0012] Preferably, in the step (a), the molar ratio of imidazole-2-carboxaldehyde to zinc nitrate hexahydrate is (2-2.2):1.
[0013] Preferably, in step (a), the mass volume ratio of imidazole-2-carboxaldehyde to triethylamine is 7:(8-12).
[0014] Preferably, in step (a), the heating reflux reaction temperature is 65 to 80° C. and the time is 20 to 50 min.
[0015] Preferably, in step (b), the mass volume ratio of ZIF-90 to sodium bisulfite solution is 1:(0.8-1.2).
[0016] Preferably, in step (b), the sodium bisulfite solution is a saturated solution with a pH value of 6.0.
[0017] Preferably, in step (b), the heating reflux reaction temperature is 60 to 80° C. and the time is 8 to 30 hours.
[0018] Preferably, in step (c), the acid solution is dilute sulfuric acid with a pH value of 4; and the treatment time is 20 to 30 hours.
[0019] The second aspect of the present invention provides a MOFs catalyst for the synthesis of bisetherfluorene obtained by the above preparation method.
[0020] The third aspect of the present invention provides an application of the MOFs catalyst for bisether fluorene synthesis obtained by the above preparation method in catalyzing the synthesis of bisether fluorene.
[0021] The fourth aspect of the present invention also provides a method for catalytically synthesizing bisether fluorene based on the above-mentioned MOFs catalyst for synthesizing bisether fluorene, the method comprising the following steps:
[0022] 9-Fluorenone, phenoxyethanol, solvent, thioglycolic acid and MOFs catalyst are mixed, and heated under stirring conditions for reflux reaction. After the reaction is completed, the catalyst is removed by suction filtration, the solvent is removed by rotary evaporation, and then diether fluorene is obtained by recrystallization.
[0023] The molar ratio of the MOFs catalyst, thioglycolic acid, 9-fluorenone and phenoxyethanol is (0.02-0.10):0.002:(0.9-1.1):(2-3);
[0024] The reflux reaction temperature is 60-100°C and the time is 1-8h;
[0025] The solvent used for recrystallization was acetone-toluene.
[0026] Compared with the prior art, the beneficial effects of the present invention include at least:
[0027] The MOFs catalyst for the synthesis of bisetherfluorene of the present invention has good water and thermal stability; there are strong acid functional groups in the structure, the acid strength is evenly distributed, and the acid site density is high; in addition, the MOFs catalyst has a porous structure, a large specific surface area, and a high catalytic efficiency.
[0028] The MOFs catalyst for bisetherfluorene synthesis of the present invention is in solid state, easy to separate, does not corrode equipment, does not generate harmful gases, has little environmental pollution, and has good recyclability; moreover, it can be recycled for more than 5 times through simple treatment, and the activity of the MOFs catalyst decreases less. DETAILED DESCRIPTION
[0029] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.
[0030] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.
[0031] The embodiment of the present invention provides a method for preparing a MOFs catalyst for the synthesis of bisetherfluorene, the preparation method comprising the following steps:
[0032] (a) dissolving imidazole-2-carboxaldehyde and triethylamine in methanol to obtain solution A; dissolving zinc nitrate hexahydrate in methanol to obtain solution B; mixing solution A and solution B and heating them under reflux for reaction, cooling, washing and drying after the reaction is completed to obtain white powder ZIF-90;
[0033] (b) dissolving ZIF-90 in methanol, adding sodium bisulfite solution and heating under reflux reaction, cooling, washing and drying after the reaction is completed to obtain white powder ZIF-90-SO3Na;
[0034] (c) placing ZIF-90-SO3Na in an acid solution for a period of time, washing, and drying to obtain the MOFs catalyst for the synthesis of bisetherfluorene.
[0035] The MOFs catalyst for bisetherfluorene synthesis prepared by the preparation method of the present invention has a strong acid functional group in its structure, has a uniform acid strength distribution, a high acid site density, and good water and thermal stability; in addition, the MOFs catalyst has a porous structure, a large specific surface area, and a high catalytic efficiency.
[0036] In some embodiments, in the step (a), the molar ratio of imidazole-2-carboxaldehyde to zinc nitrate hexahydrate may be (2-2.2):1.
[0037] In some embodiments, in the step (a), the mass volume ratio of imidazole-2-carboxaldehyde to triethylamine may be 7:(8-12).
[0038] In some embodiments, in step (a), the heating reflux reaction temperature is 65 to 80° C. and the time is 20 to 50 min.
[0039] In some embodiments, in step (b), the mass volume ratio of ZIF-90 to sodium bisulfite solution is 1:(0.8-1.2).
[0040] In some embodiments, in step (b), the sodium bisulfite solution is a saturated solution with a pH value of 6.0.
[0041] In some embodiments, in step (b), the heating reflux reaction temperature is 60 to 80° C. and the time is 8 to 30 hours.
[0042] In some embodiments, in step (c), the acid solution is dilute sulfuric acid with a pH value of 4; and the treatment time is 20 to 30 hours.
[0043] Another embodiment of the present invention provides a MOFs catalyst for the synthesis of bisetherfluorene prepared by the above preparation method.
[0044] Another embodiment of the present invention provides an application of the MOFs catalyst for bisether fluorene synthesis obtained by the above preparation method in catalyzing the synthesis of bisether fluorene.
[0045] Another embodiment of the present invention provides a method for catalytically synthesizing bisether fluorene based on the above-mentioned MOFs catalyst for bisether fluorene synthesis, the method comprising the following steps:
[0046] 9-fluorenone, phenoxyethanol, solvent, thioglycolic acid and MOFs catalyst are mixed, and heated under reflux reaction under stirring conditions. After the reaction is completed, the catalyst is removed by suction filtration, the solvent is removed by rotary evaporation, and then recrystallization is performed to obtain bisetherfluorene.
[0047] Furthermore, the molar ratio of the MOFs catalyst, thioglycolic acid, 9-fluorenone, and phenoxyethanol is (0.02-0.10): 0.002: (0.9-1.1): (2-3);
[0048] The reflux reaction temperature is 60-100°C and the time is 1-8h;
[0049] The solvent used for recrystallization was acetone-toluene.
[0050] The technical solution of the present invention is further described in detail below through specific embodiments.
[0051] Example 1
[0052] This embodiment is a method for preparing a MOFs catalyst for the synthesis of bisetherfluorene, and the preparation method comprises the following steps:
[0053] (a) 7 g of imidazole-2-carboxaldehyde and 10 ml of triethylamine were dissolved in 250 ml of methanol under stirring conditions, which was recorded as solution A. 10 g of Zn(NO3)2·6H2O was dissolved in 250 ml of methanol, which was recorded as solution B. Solution B was poured into solution A, refluxed at 70°C for 30 min, cooled naturally to room temperature, washed with methanol and filtered three times, and dried at 60°C to obtain white powder ZIF-90 with a yield of about 30%;
[0054] (b) Prepare a saturated sodium bisulfite solution with a pH of 6 for later use; dissolve 1 g of ZIF-90 in 200 ml of methanol solution, add 1 ml of sodium bisulfite solution, reflux at 60° C. for 24 h, cool naturally to room temperature, wash and filter three times with methanol, and dry at 60° C. to obtain white powder ZIF-90-SO3Na;
[0055] (c) ZIF-90-SO3Na was treated in dilute sulfuric acid at pH 4 for 24 h, washed with methanol for 3 times, filtered, and dried at room temperature to obtain a MOFs catalyst for the synthesis of bisetherfluorene.
[0056] Example 2
[0057] This embodiment is a method for preparing a MOFs catalyst for the synthesis of bisetherfluorene, and the preparation method comprises the following steps:
[0058] (a) 7 g of imidazole-2-carboxaldehyde and 10 ml of triethylamine were dissolved in 250 ml of methanol under stirring conditions, which was recorded as solution A. 10 g of Zn(NO3)2·6H2O was dissolved in 250 ml of methanol, which was recorded as solution B. Solution B was poured into solution A, refluxed at 70°C for 30 min, cooled naturally to room temperature, washed with methanol and filtered three times, and dried at 60°C to obtain white powder ZIF-90 with a yield of about 30%;
[0059] (b) Prepare a saturated sodium bisulfite solution with a pH of 6 for later use; dissolve 1 g of ZIF-90 in 200 ml of methanol solution, add 1 ml of sodium bisulfite solution, reflux at 60° C. for 8 h, cool naturally to room temperature, wash and filter three times with methanol, and dry at 60° C. to obtain white powder ZIF-90-SO3Na;
[0060] (c) ZIF-90-SO3Na was treated in dilute sulfuric acid at pH 4 for 24 h, washed with methanol for 3 times, filtered, and dried at room temperature to obtain a MOFs catalyst for the synthesis of bisetherfluorene.
[0061] Example 3
[0062] This embodiment is a method for synthesizing bisether fluorene, and the method for synthesizing bisether fluorene comprises the following steps:
[0063] In a 100mL reactor, 30ml of solvent methanol, the MOFs catalyst for the synthesis of bisether fluorene in Example 1, thioglycolic acid, 9-fluorenone, and phenoxyethanol were added in sequence, wherein the molar ratio of the MOFs catalyst for the synthesis of bisether fluorene, thioglycolic acid, 9-fluorenone, and phenoxyethanol was 0.10:0.002:1:2.8; then, under stirring conditions, slowly heated to 80°C for reflux reaction for 5h. After the reaction was completed, the catalyst was removed by suction filtration, the solvent was removed by rotary evaporation, and then recrystallization was performed using an acetone-toluene solution to obtain pure bisether fluorene with a yield of about 94%.
[0064] Example 4
[0065] This embodiment is a method for synthesizing bisether fluorene, and the method for synthesizing bisether fluorene comprises the following steps:
[0066] In a 100mL reactor, 30ml of solvent methanol, the MOFs catalyst for the synthesis of bisether fluorene in Example 2, thioglycolic acid, 9-fluorenone, and phenoxyethanol were added in sequence, wherein the molar ratio of the MOFs catalyst for the synthesis of bisether fluorene, thioglycolic acid, 9-fluorenone, and phenoxyethanol was 0.10:0.002:1:2.8; then, under stirring conditions, slowly heated to 80°C for reflux reaction for 5h. After the reaction was completed, the catalyst was removed by suction filtration, the solvent was removed by rotary evaporation, and then recrystallization was performed using acetone-toluene solution to obtain pure bisether fluorene with a yield of about 78%.
[0067] Example 5
[0068] This embodiment is a method for synthesizing bisether fluorene, and the method for synthesizing bisether fluorene comprises the following steps:
[0069] In a 100mL reactor, 30ml of solvent methanol, MOFs catalyst for synthesis of bisetherfluorene, thioglycolic acid, 9-fluorenone, and phenoxyethanol were added in sequence, wherein the molar ratio of MOFs catalyst for synthesis of bisetherfluorene, thioglycolic acid, 9-fluorenone, and phenoxyethanol was 0.10:0.002:1:2.8; then, under stirring conditions, slowly heated to 80°C for reflux reaction for 5h. After the reaction was completed, the catalyst was removed by suction filtration, the solvent was removed by rotary evaporation, and then pure bisetherfluorene was obtained by recrystallization using acetone-toluene solution with a yield of 80%.
[0070] The MOFs catalyst used for the synthesis of bisetherfluorene is the catalyst obtained by washing and drying the catalyst after the reaction in Example 3 with methanol and then reusing the catalyst for the second time.
[0071] Comparative Example 1
[0072] This comparative example is a method for synthesizing bisether fluorene, which comprises the following steps:
[0073] In a 100mL reaction kettle, 30ml of solvent methanol, thioglycolic acid, 9-fluorenone and phenoxyethanol were added in sequence. The molar ratio of thioglycolic acid, 9-fluorenone and phenoxyethanol was 0.002:1:2.8. Then, under stirring conditions, the mixture was slowly heated to 80°C for reflux reaction for 5h. After the reaction was completed, the solvent was removed by rotary evaporation, and then recrystallization was performed using acetone-toluene solution to obtain pure diether fluorene with a yield of 25%.
[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.
Claims
1. A method for preparing a MOFs catalyst for the synthesis of bisetherfluorene, characterized in that: The preparation method comprises the following steps: (a) dissolving imidazole-2-carboxaldehyde and triethylamine in methanol to obtain solution A; dissolving zinc nitrate hexahydrate in methanol to obtain solution B; mixing solution A and solution B and heating them under reflux for reaction, cooling, washing and drying after the reaction is completed to obtain white powder ZIF-90; (b) dissolving ZIF-90 in methanol, adding sodium bisulfite solution and heating under reflux reaction, cooling, washing and drying after the reaction is completed to obtain white powder ZIF-90-SO3Na; (c) placing ZIF-90-SO3Na in an acid solution for a period of time, washing, and drying to obtain the MOFs catalyst for the synthesis of bisetherfluorene.
2. The preparation method according to claim 1, characterized in that: In the step (a), the molar ratio of imidazole-2-carboxaldehyde to zinc nitrate hexahydrate is (2-2.2):
1.
3. The preparation method according to claim 1, characterized in that: In the step (a), the mass volume ratio of imidazole-2-carboxaldehyde to triethylamine is 7:(8-12).
4. The preparation method according to claim 1, characterized in that: In the step (a), the heating reflux reaction temperature is 65 to 80° C. and the time is 20 to 50 minutes.
5. The preparation method according to claim 1, characterized in that: In the step (b), the mass volume ratio of ZIF-90 to the sodium bisulfite solution is 1: (0.8-1.2).
6. The preparation method according to claim 1, characterized in that: In the step (b), the sodium bisulfite solution is a saturated solution with a pH value of 6.
0.
7. The preparation method according to claim 1, characterized in that: In the step (b), the heating reflux reaction temperature is 60 to 80° C. and the time is 8 to 30 hours.
8. The preparation method according to claim 1, characterized in that: In the step (c), the acid solution is dilute sulfuric acid with a pH value of 4; and the treatment time is 20 to 30 hours.
9. A MOFs catalyst for the synthesis of bisetherfluorene obtained by the preparation method according to any one of claims 1 to 8.
10. Use of the MOFs catalyst for bisetherfluorene synthesis obtained by the preparation method according to any one of claims 1 to 8 in catalyzing the synthesis of bisetherfluorene.