A COF polymer based on double hydrogen bonds and its preparation method and application
By constructing a COF polymer based on double hydrogen bonds, the problem of catalyst deactivation was solved, and efficient and stable catalytic performance was achieved. It is suitable for multiple cycles and improves the efficiency and stability of the catalytic reaction.
Patent Information
- Application Number
- CN202411138546.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-19
- Publication Date
- 2025-09-23
- Estimated Expiration
- 2044-08-19
AI Technical Summary
Existing double hydrogen bond materials are easily deactivated in catalysts due to dimerization or polymerization, affecting catalytic efficiency and stability, making it difficult to meet the needs of chemical reactions.
By designing a COF polymer based on double hydrogen bonds, a specific precursor polymer and phenylhydrazine are used to construct a highly stable double hydrogen bond structure in a solvent thermal reaction, forming a triazole heterocycle, enhancing the number and strength of hydrogen bonds, and preparing a COF polymer with a porous structure.
It achieves high stability and efficient catalytic performance. As a catalyst, it can be recycled more than six times, maintaining more than 90% catalytic activity, significantly improving the yield of catalytic oxidation synthesis of benzylamine.
Smart Images
Figure CN119039544B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of porous organic polymer materials, and in particular to a COF polymer based on double hydrogen bonds, and a preparation method and application thereof. Background Art
[0002] The information disclosed in this background technology section is only intended to enhance 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 those 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 catalytic stability and activity.
[0004] Double hydrogen bonds, as an important non-covalent bond, have a wide range of applications in organic chemistry, biochemistry, and materials science. Among them, in organic synthesis, the application of double hydrogen bonds is reflected in many aspects. For example, by designing and developing new materials containing double hydrogen bonds, precise control of intermolecular interactions can be achieved, thereby affecting the rate of chemical reactions and product distribution. In addition, the polarity of double hydrogen bonds and interactions with solvents can also be used to optimize reaction conditions and improve the selectivity and yield of reactions. Organic small molecule compounds containing double 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 bond interactions, which inevitably leads to the deactivation of the catalyst in the reaction. Therefore, research and development of new and stable double hydrogen bond materials is of great significance to promoting the development of organic synthesis. Summary of the Invention
[0005] In order to overcome the above problems, the present invention provides a COF polymer based on double hydrogen bonds and a preparation method and application thereof.
[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:
[0007] The first aspect of the present invention provides a precursor polymer of a COF polymer based on double hydrogen bonds, wherein the precursor polymer has a structure represented by formula (I) as a structural repeating unit;
[0008]
[0009] Formula (I).
[0010] The second aspect of the present invention provides a method for preparing the precursor polymer described in the first aspect, comprising:
[0011] The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) and 1,4-diphenylurea (BDU) were dispersed in an organic solvent and subjected to solvothermal reaction to obtain a precursor polymer.
[0012] The third aspect of the present invention provides use of the precursor polymer described in the first aspect and / or the precursor polymer prepared by the preparation method described in the second aspect in the preparation of a COF polymer based on double hydrogen bonds.
[0013] The fourth aspect of the present invention provides a COF polymer based on double hydrogen bonds, wherein the COF polymer based on double hydrogen bonds has the structure represented by formula (II) as a structural repeating unit.
[0014]
[0015] Formula (II).
[0016] A fifth aspect of the present invention provides a method for preparing the COF polymer based on double hydrogen bonds according to the fourth aspect, comprising:
[0017] The precursor polymer described in the first aspect and phenylhydrazine (PHZ) are dispersed in an organic solvent, a catalyst is added, and a COF polymer based on double hydrogen bonds is obtained by solvent thermal reaction.
[0018] The sixth aspect of the present invention provides the use of the COF polymer based on double hydrogen bonds described in the third aspect and / or the COF polymer based on double hydrogen bonds prepared by the preparation method described in the fifth aspect as a catalyst.
[0019] The beneficial effects of the present invention include:
[0020] (1) In the present invention, the imine bond in the single hydrogen bond precursor polymer is locked to form a triazole heterocycle, thereby constructing a highly stable double hydrogen bond COF polymer. The synthetic method of locking the imine bond into a triazole heterocycle structure provides a novel method for the construction of double hydrogen bonds.
[0021] (2) The double hydrogen bond-based COF polymer provided in the present invention has a higher number and strength of hydrogen bonds than single hydrogen bond compounds, providing a good structural match for nitrogen-rich or oxygen-rich functional groups. This makes the double hydrogen bond-based COF polymer more suitable for binding to reaction substrates, thereby promoting chemical catalytic conversion and effectively improving the activity of benzylamine catalytic oxidation to N-benzyl-1-phenylformimine. At the same time, as a structurally stable heterogeneous catalyst, the double hydrogen bond-based COF polymer can be recycled more than six times, and the yield is maintained at more than 90%. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The accompanying drawings, 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.
[0023] Figure 1 is a scanning electron microscope image of the precursor polymer prepared in Example 1;
[0024] Figure 2 This is a thermogravimetric image of the precursor polymer prepared in Example 1;
[0025] Figure 3 is the PXRD pattern of the precursor polymer prepared in Example 1;
[0026] Figure 4 N2 adsorption image of the precursor polymer prepared in Example 1;
[0027] Figure 5 is a scanning electron microscope image of the double hydrogen bond-based COF polymer prepared in Example 2;
[0028] Figure 6 Thermogravimetric image of the COF polymer based on double hydrogen bonds prepared in Example 2
[0029] Figure 7 PXRD pattern of the COF polymer based on double hydrogen bonds prepared in Example 2
[0030] Figure 8 N2 adsorption image of the COF polymer based on double hydrogen bonds prepared in Example 2;
[0031] Figure 9 PXRD pattern of COF polymer based on double hydrogen bonds after 5 cycles. DETAILED DESCRIPTION
[0032] It should be noted that the following detailed descriptions are exemplary and 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.
[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.
[0034] 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 with reference to specific embodiments.
[0035] A first typical embodiment of the present invention provides a precursor polymer of a COF polymer based on double hydrogen bonds, wherein the precursor polymer has a structure represented by formula (I) as a structural repeating unit.
[0036]
[0037] Formula (I).
[0038] A second typical embodiment of the present invention provides a method for preparing the precursor polymer described in the first aspect, comprising:
[0039] The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) and 1,4-diphenylurea (BDU) were dispersed in an organic solvent and subjected to solvothermal reaction to obtain a precursor polymer.
[0040] In one or more embodiments, the ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene and 1,4-diphenylurea are dispersed in an organic solvent and then a catalyst is added to conduct a solvothermal reaction.
[0041] Preferably, the catalyst comprises glacial acetic acid.
[0042] More preferably, the molar ratio of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) to glacial acetic acid is 5:0.8-1.2, preferably 5:1.
[0043] In one or more embodiments, the organic solvent comprises a mixed solvent of o-dichlorobenzene and n-butanol;
[0044] Preferably, the volume ratio of o-dichlorobenzene to n-butanol is 8.8-9.2:1, preferably 9:1.
[0045] In one or more embodiments, the molar ratio of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene to 1,4-diphenylurea is 1:1.8-2.2, preferably 1:2.
[0046] In one or more embodiments, the concentration of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene in the organic solvent is 0.8-1.2 mmol / L, preferably 1.0 mmol / L.
[0047] In one or more embodiments, the temperature of the solvothermal reaction is 140-160° C., preferably 150° C.; the time of the solvothermal reaction is 115-125 h, preferably 120 h.
[0048] A third typical embodiment of the present invention provides use of the precursor polymer described in the first aspect and / or the precursor polymer prepared by the preparation method described in the second aspect in the preparation of a COF polymer based on double hydrogen bonds.
[0049] A fourth typical embodiment of the present invention provides a COF polymer based on double hydrogen bonds, wherein the COF polymer based on double hydrogen bonds has a structure represented by formula (II) as a structural repeating unit.
[0050]
[0051] Formula (II).
[0052] A fifth typical embodiment of the present invention provides a method for preparing the COF polymer based on double hydrogen bonds according to the fourth aspect, comprising:
[0053] The precursor polymer described in the first aspect and phenylhydrazine (PHZ) are dispersed in an organic solvent, a catalyst is added, and a COF polymer based on double hydrogen bonds is obtained by solvent thermal reaction.
[0054] In one or more embodiments, the organic solvent comprises a dimethyl sulfoxide aqueous solution, wherein the volume ratio of dimethyl sulfoxide to deionized water is 1.5 to 3:1, preferably 2:1.
[0055] In one or more embodiments, the molar ratio of the precursor polymer to phenylhydrazine is 65 to 75:1, preferably 70:1.
[0056] In one or more embodiments, the concentration of phenylhydrazine in the organic solvent solution is 0.8 to 1.2 mmol / L, preferably 1.0 mmol / L.
[0057] In one or more embodiments, the catalyst comprises potassium hydroxide.
[0058] Preferably, the molar ratio of phenylhydrazine to potassium hydroxide is 1.8 to 2.2:1, preferably 2:1.
[0059] In one or more embodiments, the temperature of the solvothermal reaction is 140-160° C., preferably 150° C.; the time of the solvothermal reaction is 70-80 h, preferably 72 h.
[0060] A sixth typical embodiment of the present invention provides the use of the COF polymer based on double hydrogen bonds described in the third aspect and / or the COF polymer based on double hydrogen bonds prepared by the preparation method described in the fifth aspect as a catalyst.
[0061] In one or more embodiments, the application includes catalyzing the synthesis of N-benzyl-1-phenylformimine from benzylamine.
[0062] 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 with reference to specific embodiments.
[0063] Example 1
[0064] Preparation of the precursor polymer represented by formula (I):
[0065] The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene (0.05 mmol, 15.0 mg) and 1,4-phenylenediurea (0.1 mmol, 10.0 mg) were placed in a pressure-resistant glass tube, acetic acid (0.01 mmol, 20 μL) was added as a catalyst, and then 35 mL of a mixed solution of o-dichlorobenzene and n-butanol (volume ratio of 9:1) was added. The mixed solution was placed in a liquid nitrogen bath, frozen-thawed, and degassed three times. After sealing, it was placed in an oven and programmed to rise from room temperature to 150 °C within 24 h. The reaction was continued at 150 °C for 120 h, and then the heating was stopped. After the oven temperature dropped to room temperature, the solid in the glass tube was removed, washed thoroughly with DMF, H2O, and tetrahydrofuran, respectively, and dried in vacuo to obtain a yellow crystalline powder, which is the precursor polymer represented by formula (I).
[0066] The precursor polymer represented by formula (I) prepared in this example was characterized. Figure 1 is the scanning electron microscope image of the precursor polymer. Figure 2 is the thermogravimetric image of the precursor polymer, Figure 3 is the PXRD pattern of the precursor polymer, Figure 4 This is the N2 adsorption image of the precursor polymer. Figure 1 、 Figure 3 and Figure 4 It can be seen from the figure that the precursor polymer prepared in this embodiment has a porous structure. Figure 2 and Figure 3 It can be seen that the precursor polymer is a crystalline porous material with high thermal stability.
[0067] Example 2
[0068] Preparation of COF polymers based on double hydrogen bonds:
[0069] The precursor polymer represented by formula (I) prepared in Example 1 (31.5 mmol, 18.0 mg) and phenylhydrazine (0.45 mmol, 4.8 μL) were placed in a pressure-resistant glass tube, potassium hydroxide (0.315 mmol, 17.8 mg) was added as a catalyst, and then 0.5 mL of an aqueous solution of dimethyl sulfoxide (DMSO) was added (volume ratio of 2:1). The mixed solution was placed in a liquid nitrogen bath and frozen-thawed and degassed three times. After sealing, it was placed in an oven and programmed to rise from room temperature to 150°C within 24 hours. After reacting at 150°C for 72 hours, heating was stopped. After the oven temperature dropped to room temperature, the solid in the glass tube was taken out, washed thoroughly with DMF, H2O and tetrahydrofuran, respectively, and then dried in vacuum to obtain a yellow crystalline powder, which is a COF polymer based on double hydrogen bonds.
[0070] The double hydrogen bond-based COF polymer prepared in this example was characterized. Figure 5 This is a scanning electron microscope image of a COF polymer based on double hydrogen bonds. Figure 6 Thermogravimetric images of COF polymers based on double hydrogen bonds. Figure 7 PXRD pattern of COF polymer based on double hydrogen bonds. Figure 8 This is the N2 adsorption image of COF polymer based on double hydrogen bonds. Figure 5 、 Figure 7 and Figure 8 It can be seen from the figure that the COF polymer based on double hydrogen bonds prepared in this embodiment has a porous structure. Figure 6-Figure 7 It can be seen that the COF polymer based on double hydrogen bonds is a crystalline porous material with high thermal stability.
[0071] Experimental Example 1
[0072] The double hydrogen bond-based COF polymer prepared in Example 2 was used as a catalyst to catalyze the oxidation reaction of benzylamine.
[0073] The preparation process involved adding benzylamine (0.25 mmol, 26.8 mg) and a dihydrogen-bonded COF polymer (0.01 mmol, 16.0 mg) to a 25 mL reaction vial. 2 mL of water was added as solvent. The reaction was allowed to proceed at 60°C for 10 h. After the reaction, the temperature was lowered to room temperature, and the TBA-COF was isolated by centrifugation. The reaction yield was determined using gas chromatography-mass spectrometry (GC-MS).
[0074] The specific reaction equation is as follows:
[0075]
[0076] 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 six cycles. The reaction yield was determined by gas chromatography-mass spectrometry (GC-MS). The catalytic effect is shown in Table 1. Figure 9 The PXRD pattern of the catalyst after 5 cycles is shown in Figure 2. Figure 9 It can be seen that after five cycles of the catalyst, the COF polymer framework based on double hydrogen bonds has not changed. As can be seen from Table 1, the product yield remains basically consistent, showing only a slight downward trend after six cycles, reflecting the excellent stability of the catalyst. It can be reused more than six times, which can significantly improve catalyst utilization and reduce production costs.
[0077] Table 1 Catalytic effect of multiple cyclic reactions of COF polymers based on double hydrogen bonds
[0078]
[0079] The COF polymer based on double hydrogen bonds provided by the present invention was used as a catalyst for the oxidation of benzylamine, achieving a yield of 96%. Furthermore, after six cycles of reaction, the COF polymer based on double hydrogen bonds maintained a catalytic yield exceeding 90%. This demonstrates that the COF polymer based on double hydrogen bonds provided by the present invention has efficient and stable catalytic performance and can be recycled multiple times.
[0080] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.
Claims
1. A COF polymer based on double hydrogen bonds, characterized in that The COF polymer based on double hydrogen bonds has the structure shown in formula (II) as the structural repeating unit. Formula (II).
2. The method for preparing a COF polymer based on double hydrogen bonds according to claim 1, wherein: include: The precursor polymer and phenylhydrazine are dispersed in an organic solvent, a catalyst is added, and a COF polymer based on double hydrogen bonds is obtained by solvothermal reaction; The precursor polymer has the structure shown in formula (I) as a structural repeating unit, Formula (I).
3. The preparation method according to claim 2, wherein The organic solvent includes a dimethyl sulfoxide aqueous solution, wherein the volume ratio of dimethyl sulfoxide to deionized water is 1.5 to 3:1; Alternatively, the molar ratio of the precursor polymer to phenylhydrazine is 65 to 75:1; Alternatively, the concentration of phenylhydrazine in the organic solvent solution is 0.8 to 1.2 mmol / L; Alternatively, the catalyst comprises potassium hydroxide; the molar ratio of phenylhydrazine to potassium hydroxide is 1.8 to 2.2:1; Alternatively, the temperature of the solvothermal reaction is 140-160 °C; the time of the solvothermal reaction is 70-80 h.
4. The preparation method according to claim 3, wherein The volume ratio of dimethyl sulfoxide and deionized water is 2:
1.
5. The preparation method according to claim 3, wherein The molar ratio of the precursor polymer to phenylhydrazine was 70:
1.
6. The preparation method according to claim 3, wherein The concentration of phenylhydrazine in the organic solvent solution is 1.0 mmol / L.
7. The preparation method according to claim 3, wherein The molar ratio of phenylhydrazine to potassium hydroxide is 2:
1.
8. The preparation method according to claim 3, wherein The solvothermal reaction temperature was 150 °C and the solvothermal reaction time was 72 h.
9. The preparation method according to claim 2, wherein The method for preparing the precursor polymer comprises: The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene and 1,4-diphenylurea are dispersed in an organic solvent and subjected to a solvothermal reaction to obtain a precursor polymer.
10. The preparation method according to claim 9, wherein The ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene and 1,4-diphenylurea were dispersed in an organic solvent and then a catalyst was added to carry out a solvothermal reaction.
11. The preparation method according to claim 10, characterized in that The catalyst includes glacial acetic acid.
12. The preparation method according to claim 11, characterized in that The molar ratio of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene to glacial acetic acid is 5:0.8~1.
2.
13. The preparation method according to claim 12, wherein The molar ratio of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene to glacial acetic acid is 5:
1.
14. The preparation method according to claim 9, wherein The organic solvent includes a mixed solvent of o-dichlorobenzene and n-butanol; Alternatively, the molar ratio of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene to 1,4-diphenylurea is 1:1.8-2.2; Alternatively, the concentration of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene in the organic solvent is 0.8 to 1.2 mmol / L; Alternatively, the temperature of the solvothermal reaction is 140-160°C; the time of the solvothermal reaction is 115-125 h.
15. The preparation method according to claim 14, wherein The volume ratio of o-dichlorobenzene to n-butanol is 8.8~9.2:
1.
16. The preparation method according to claim 15, characterized in that The volume ratio of o-dichlorobenzene to n-butanol is 9:
1.
17. The preparation method according to claim 14, wherein The molar ratio of the ligands 1,3,6,8-tetrakis(4-formylphenyl)pyrene and 1,4-diphenylurea was 1:
2.
18. The preparation method according to claim 14, wherein The concentration of the ligand 1,3,6,8-tetrakis(4-formylphenyl)pyrene in the organic solvent was 1.0 mmol / L.
19. The preparation method according to claim 14, wherein The solvothermal reaction temperature was 150 °C and the solvothermal reaction time was 120 h.
20. Use of the COF polymer based on double hydrogen bonds according to claim 1 and / or the COF polymer based on double hydrogen bonds prepared by the preparation method according to any one of claims 2 to 19 as a catalyst.
21. The use according to claim 20, characterized in that The application includes catalyzing the synthesis of N-benzyl-1-phenylformimine from benzylamine.