PA-COF polymer as well as preparation method and application thereof
By synthesizing a highly stable hydrogen-bonded COF polymer with urea-like active sites, the problem of inactivation of existing catalysts due to intermolecular hydrogen bond interactions is solved, efficient and stable catalytic performance is achieved, and the utilization rate of the catalyst is significantly improved.
Patent Information
- Application Number
- CN202510047592.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-13
- Publication Date
- 2025-04-22
AI Technical Summary
In organic synthesis, existing hydrogen bond-containing catalysts are prone to dimerization or polymerization due to intermolecular hydrogen bond interactions, resulting in catalyst deactivation and difficulty in maintaining stability and efficient catalytic performance.
A highly stable hydrogen-bonded COF polymer with urea-like active sites was synthesized by solvothermal method using 1,4-diphenylurea (BDU) as a new monomer, combining 1,3,6,8-tetrade (4-formylphenyl)pyrene (TFPPy) and 4-hydrazine benzenesulfonic acid (PHPA).
PA-COF polymer has higher crystallinity and thermal stability, and can maintain high yields (up to 99%) in the Friedel-Crafts reaction of catalyzed nitrostyrene and indole, and maintain a catalytic efficiency of more than 90% after ten cycles, significantly improving the stability and utilization of the catalyst.
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Figure CN119859228A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of porous organic polymer materials, and specifically relates to a PA-COF polymer and a preparation method and application thereof. Background Art
[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.
[0003] Covalent organic frameworks (COFs), as an emerging type of porous crystalline polymers in two-dimensional materials, have size-adjustable nanopores, high specific surface area, good chemical stability, and uniformly dispersed catalytic active sites, thus improving the catalytic stability and catalytic activity.
[0004] Hydrogen bonding is an important intermolecular interaction force, which plays an important role in the structure, stability, physical properties and chemical reactions of molecules. Among them, in organic synthesis, the application of hydrogen bonding is reflected in many aspects. For example, hydrogen bonding can affect the product selectivity of chemical reactions. In organic synthesis, during the reaction, the presence or destruction of hydrogen bonding can lead to the generation of different conformations, thereby selectively forming specific products. The presence of hydrogen bonding can regulate the orientation of reactants, making specific reaction channels easier to proceed and producing specific products. In addition, the polarity of hydrogen bonds and the interaction with solvents can also be used to optimize reaction conditions and improve the selectivity and yield of reactions. The presence of hydrogen bonding can reduce the activation energy of the reaction, thereby accelerating the reaction rate. Organic small molecule compounds containing hydrogen bonds are a typical class of catalysts that can efficiently catalyze organic reactions. However, this type of compound is prone to self-dimerization or polymerization through intermolecular hydrogen bonding interactions, which inevitably leads to the deactivation of the catalyst in the reaction. Therefore, the research and development of new stable hydrogen-bonded materials is of great significance to promote the development of organic synthesis. Summary of the invention
[0005] In order to solve the deficiencies of the prior art, the object of the present invention is to provide a PA-COF polymer and a preparation method and application thereof.
[0006] In order to achieve the above object, the technical solution of the present invention is:
[0007] In a first aspect, the present invention provides a PA-COF polymer, wherein the PA-COF polymer has a structure represented by formula (I) as a structural repeating unit;
[0008]
[0009] The PA-COF polymer is a COF polymer containing hydrogen bonds.
[0010] In a second aspect, the present invention provides a method for preparing the PA-COF polymer described in the first aspect, comprising:
[0011] The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy), 1,4-diphenylurea (BDU) and 4-hydrazinobenzenesulfonic acid (PHPA) were dispersed in an organic solvent and the PA-COF polymer was obtained by solvothermal reaction.
[0012] In a third aspect, the present invention provides use of the PA-COF polymer described in the first aspect and / or the PA-COF polymer prepared by the preparation method described in the second aspect as a catalyst.
[0013] In a fourth aspect, the present invention provides a method for catalyzing the Friedel-Crafts alkylation reaction of nitrostyrene and indole, comprising the following steps:
[0014] The nitrostyrene derivative, the indole derivative and the above-mentioned PA-COF polymer are dissolved in an organic solvent and reacted at room temperature to obtain the product.
[0015] One or some of the above technical solutions have the following advantages or beneficial effects:
[0016] (1) In the present invention, 1,4-diphenylurea (BDU) is used as a new monomer to replace the conventional ammonia monomer and 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPY) and 4-hydrazinobenzenesulfonic acid (PHPA) to synthesize a highly stable hydrogen-bonded COF polymer (PA-COF) with urea-like active sites by a solvothermal method.
[0017] (2) The PA-COF of the present invention has higher crystallinity and stability (thermal stability up to 200° C.). PA-COF, as a heterogeneous catalyst, has a yield of up to 99% in the Friedel-Crafts reaction of nitrostyrene and indole, and can be repeatedly cycled ten times while retaining good crystallinity. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.
[0019] Figure 1 is a scanning electron microscope image of the PA-COF polymer prepared in Example 1 of the present invention;
[0020] Figure 2 This is a thermogravimetric image of the PA-COF polymer prepared in Example 1 of the present invention;
[0021] Figure 3 is the PXRD image of the PA-COF polymer prepared in Example 1 of the present invention;
[0022] Figure 4 is an infrared image of the PA-COF polymer prepared in Example 1 of the present invention;
[0023] Figure 5 This is the N2 adsorption image of the PA-COF polymer prepared in Example 1 of the present invention;
[0024] Figure 6 This is the PXRD image of PA-COF polymer after 10 cycles as a catalyst in Experimental Example 1 of the present invention. DETAILED DESCRIPTION
[0025] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.
[0026] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.
[0027] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.
[0028] A first typical embodiment of the present invention provides a PA-COF polymer, wherein the PA-COF polymer has a structure represented by formula (I) as a structural repeating unit,
[0029]
[0030] The PA-COF polymer is a COF polymer containing hydrogen bonds. PA-COF refers to a COF containing sulfonic acid.
[0031] A second typical embodiment of the present invention provides a method for preparing the PA-COF polymer according to the first aspect, comprising:
[0032] The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy), 1,4-diphenylurea (BDU) and 4-hydrazinobenzenesulfonic acid (PHPA) were dispersed in an organic solvent and the PA-COF polymer was obtained by solvothermal reaction.
[0033] In one or more embodiments, ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy), 1,4-diphenylurea (BDU) and 4-hydrazinobenzenesulfonic acid (PHPA) are dispersed in an organic solvent, and a catalyst is added to perform a solvothermal reaction.
[0034] In one or more embodiments, the catalyst includes acetic acid.
[0035] In one or more embodiments, the organic solvent comprises a mixed solution of o-dichlorobenzene and n-butanol, wherein the volume ratio of o-dichlorobenzene to n-butanol is (8.8-9.2):(0.8-1.2), preferably 9:1.
[0036] In one or more embodiments, the molar ratio of 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) to 1,4-diphenylurea (BDU) to 4-hydrazinobenzenesulfonic acid (PHPA) is (0.8-1.2):(1.8-2.2):(0.8-1.2), preferably 1:2:1.
[0037] In one or more embodiments, the concentration of 4-hydrazinobenzenesulfonic acid (PHPA) in the organic solvent solution is 20 to 30 mmol / L, preferably 25 mmol / L.
[0038] In one or more embodiments, the molar ratio of 4-hydrazinobenzenesulfonic acid (PHPA) to the catalyst is 1:(20-25), preferably 1:24.
[0039] In one or more embodiments, the temperature of the solvothermal reaction is 140 to 160° C., preferably 150° C.; the time of the solvothermal reaction is 96 to 144 h, preferably 120 h.
[0040] A third typical embodiment of the present invention provides use of the PA-COF polymer described in the first aspect and / or the PA-COF polymer prepared by the preparation method described in the second aspect as a catalyst.
[0041] Preferably, the application includes catalyzing the Friedel-Crafts reaction of nitrostyrene and indole.
[0042] A fourth typical embodiment of the present invention provides a method for catalyzing the Friedel-Crafts alkylation reaction of nitrostyrene and indole, comprising the following steps:
[0043] The nitrostyrene derivative, the indole derivative and the above-mentioned PA-COF polymer are dissolved in an organic solvent and reacted at room temperature to obtain the product.
[0044] Preferably, the organic solvent is toluene, dichloromethane, acetonitrile, methanol or chloroform, preferably dichloromethane.
[0045] Preferably, the reaction is carried out for 12-24 hours, preferably 24 hours.
[0046] Preferably, the nitrostyrene derivative is
[0047] Preferably, the indole derivative is
[0048] Preferably, the usage ratio of nitrostyrene derivative, indole derivative, PA-COF polymer and organic solvent is (80-90 mg):(90-100 mg):(10-20 mg):(1-5 mL), preferably (84-86 mg):(95-100 mg):(12-18 mg):(1-2 mL).
[0049] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.
[0050] Example 1
[0051] Preparation of COF (PA-COF) polymers containing hydrogen bonds:
[0052] The ligand 1,3,6,8-tetrakis (4-formylphenyl) pyrene (0.05mmol, 15.0mg) and 1,4-phenylenediurea (0.1mmol, 10.0mg) and 4-hydrazinobenzenesulfonic acid (PHPA) (0.05mmol, 9.4mg) were placed in a pressure-resistant glass tube, 200μL of 6M acetic acid (HOAc) and 2mL of o-dichlorobenzene / n-butanol (o-DCB / n-BuOH) (9:1v / v) were added and mixed and sealed in a Pyrex tube (35mL) and heated at 150°C for 5 days under N2. After cooling to room temperature, the solid was separated by centrifugation. The resulting powder was thoroughly washed with dichloromethane and ethanol and dried in a vacuum to obtain a yellow-green COF crystalline powder with a yield of about 74%.
[0053] The PA-COF polymer prepared in this example was characterized. Figure 1 Transmission electron microscope image of PA-COF polymer. Figure 2 Thermogravimetric image of PA-COF polymer. Figure 3 is the PXRD pattern of PA-COF polymer, Figure 4 Infrared spectrum image of PA-COF polymer. Figure 5This is the N2 adsorption image of PA-COF polymer. Figure 1 , Figure 3 and Figure 5 It can be seen from the above that the PA-COF polymer prepared in this example has a porous structure. Figure 2 It can be seen that PA-COF polymer has high thermal stability. Figure 4 The molecular structure and chemical bonds of the PA-COF polymer can be seen.
[0054] Experimental Example 1
[0055] The PA-COF polymer prepared in Example 1 was used as a catalyst in the Friedel-Crafts alkylation reaction of nitrostyrene and indole.
[0056] The preparation process is as follows: a mixture of trans-nitrostyrene (85 mg, 0.57 mmol), indole (98 mg, 0.84 mmol), and PA-COF (15 mg, 3 mol%) was dissolved in CH2Cl2 (1.5 ml), stirred at room temperature for 24 h, and after the reaction was completed, COF was separated by centrifugation. 1 H NMR) to determine the product, all of which were isolated yields, and the reaction yield was determined.
[0057] The specific reaction equation is as follows:
[0058]
[0059] The reaction was tracked by TLC. After the reaction was completed, the catalyst was recovered by centrifugation and directly put into the next cycle reaction. According to the above conditions, the catalyst was used for ten cycles. The H NMR spectrum ( 1 H NMR) was used to determine the reaction yield. The catalytic effect is shown in Table 1. Figure 5 Figure 1 shows the PXRD image of the catalyst after 10 cycles. It can be seen from Figure 1 that the PA-COF polymer framework has not changed after 10 cycles. It can be seen from Table 1 that the yield of the product remains basically the same. After ten cycles, it only shows a slight downward trend, reflecting the excellent stability of the catalyst. It can be reused for more than ten times, which can significantly improve the utilization rate of the catalyst and reduce production costs.
[0060] Table 1 Catalytic effect of multiple cycles of PA-COF polymer
[0061]
[0062] When the PA-COF polymer provided by the present invention is used as a catalyst to catalyze the Friedel-Crafts alkylation reaction of nitrostyrene and indole, the yield can reach 99%. At the same time, after the PA-COF polymer is cyclically reacted ten times, the catalytic yield is still maintained at more than 90%, which proves that the PA-COF polymer provided by the present invention has efficient and stable catalytic performance and can be recycled for multiple times.
[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A PA-COF polymer, characterized in that The PA-COF polymer has the structure shown in formula (I) as a repeating unit.
2. A method for preparing the PA-COF polymer according to claim 1, characterized in that: The following steps are involved: The ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene, 1,4-diphenylurea and 4-hydrazinobenzenesulfonic acid are dispersed in an organic solvent, and the PA-COF polymer is obtained by solvothermal reaction.
3. The preparation method according to claim 2, characterized in that: The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene, 1,4-diphenylurea and 4-hydrazinobenzenesulfonic acid are dispersed in an organic solvent, and a catalyst is added to carry out a solvothermal reaction.
4. The preparation method according to claim 3, characterized in that: The catalyst includes acetic acid; Preferably, the organic solvent comprises a mixed solution of o-dichlorobenzene and n-butanol, wherein the volume ratio of o-dichlorobenzene to n-butanol is (8.8-9.2):(0.8-1.2), and more preferably 9:
1.
5. The preparation method according to claim 3, characterized in that: The molar ratio of 1,3,6,8-tetrakis(4-formylphenyl)pyrene to 1,4-diphenylurea to 4-hydrazinobenzenesulfonic acid is (0.8-1.2):(1.8-2.2):(0.8-1.2), and more preferably 1:2:1; Preferably, the concentration of 4-hydrazinobenzenesulfonic acid in the organic solvent solution is 20 to 30 mmol / L, more preferably 25 mmol / L; Preferably, the molar ratio of 4-hydrazinobenzenesulfonic acid to the catalyst is 1:(20-25), more preferably 1:
24.
6. The preparation method according to claim 3, characterized in that: The temperature of the solvent thermal reaction is 140-160° C., preferably 150° C.; the time of the solvent thermal reaction is 96-144 h, preferably 120 h.
7. Use of the PA-COF polymer according to claim 1 and / or the PA-COF polymer prepared by the preparation method according to any one of claims 2 to 6 as a catalyst.
8. The use according to claim 7, characterized in that: The applications include catalyzing the Friedel-Crafts alkylation of nitrostyrene and indole.
9. A method for catalyzing the Friedel-Crafts alkylation reaction of nitrostyrene and indole, characterized in that: The following steps are involved: The nitrostyrene derivative, the indole derivative and the PA-COF polymer according to claim 1 are dissolved in an organic solvent and reacted at room temperature to obtain the product.
10. The method according to claim 9, characterized in that The organic solvent is toluene, dichloromethane, acetonitrile, methanol or chloroform; Preferably, the reaction is carried out for 12-24 hours; Preferably, the nitrostyrene derivative is Preferably, the indole derivative is Preferably, the usage ratio of nitrostyrene derivative, indole derivative, PA-COF polymer and organic solvent is (80-90 mg):(90-100 mg):(10-20 mg):(1-5 mL), preferably (84-86 mg):(95-100 mg):(12-18 mg):(1-2 mL).