sp 2 c-covalent organic framework materials and their preparation methods
Patent Information
- Application Number
- CN202310446647.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-04-24
- Publication Date
- 2026-09-25
- Estimated Expiration
- 2043-04-24
AI Technical Summary
[0024]本发明以1,3,5-三(4-氰基甲基苯)苯(CPTDD)为三角对称的接头分别和2,5-二乙烯基-1,4-苯二甲醛(TPA-CH＝CH2)、对苯二甲醛(TPA)、2,5-二甲氧基苯-1,4-二甲醛(TPA-OCH3)等三种醛单体缩合成一种二维蜂窝状聚合物，依次得到绿色、淡黄色和橙红色的三种sp2c-共价有机框架材料。本发明主要通过醛单体所带侧链不同，通过侧链调控制备了三种发不同荧光的sp2c-共价有机框架材料。
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Figure CN117164797B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of fluorescent material synthesis technology, and more particularly to sp 2 c-covalent organic framework materials and their preparation methods. Background Technology
[0002] Fluorescent covalent organic frameworks (LCOFs) have attracted widespread attention due to their tunable structure and unique photophysical and luminescent properties. Currently, the emission colors of LCOFs are mostly concentrated in blue, green, and yellow. To change the fluorescence of LCOFs and produce other fluorescent colors, it is usually achieved by adjusting their conjugation degree. However, how to prepare LCOFs with other emission colors remains a problem to be solved. Summary of the Invention
[0003] (a) Technical problems to be solved
[0004] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a sp 2 c-covalent organic framework materials and their preparation methods were described, including the synthesis of three sp materials in green, pale yellow, and orange-red colors. 2 c-covalent organic framework materials enrich the variety of fluorescent covalent organic frameworks (LCOFs) and expand their applicable environments.
[0005] (II) Technical Solution
[0006] Firstly, the present invention provides sp 2 c-covalent organic framework materials are two-dimensional honeycomb polymers composed of the following structural units;
[0007]
[0008] Wherein, R = H, OCH3, or CH = CH2.
[0009] Preferably, the product fluoresces pale yellow when R=H; orange-red when R=OCH3; and green when R=CH=CH2.
[0010] Secondly, this invention provides sp 2 A method for preparing c-covalent organic framework materials, the method comprising:
[0011] S1. The aldehyde monomer and CPTDD are dissolved in a mixed solvent of mesitylene and 1,4-dioxane, and ultrasonically mixed to obtain a mixed solution; the aldehyde monomer is 2,5-divinyl-1,4-phenylenedialdehyde, terephthalaldehyde, or 2,5-dimethoxybenzene-1,4-dicarboxaldehyde.
[0012] S2. Under inert atmosphere or vacuum conditions, add acid or alkaline solution as a catalyst to the mixed solution to cause the aldehyde monomer to undergo a condensation reaction with CPTDD. React at 105℃-125℃ for 60-84h. After the reactor is cooled to room temperature, centrifuge at 8000-12000rpm to obtain the precipitate.
[0013] S3. The precipitate was centrifuged and washed sequentially with DMF and ethanol as detergents to remove adsorbed impurities. The precipitate was then dried and ground to obtain a powder. 2 c-covalent organic framework materials.
[0014] Wherein, when the aldehyde monomer is 2,5-divinyl-1,4-benzaldehyde, the product is a green fluorescent powder (denoted as: CPTDD-TPA-CH=CH2 material); when the aldehyde monomer is terephthalaldehyde, the product is a pale yellow fluorescent powder (denoted as: CPTDD-TPA material); and when the aldehyde monomer is 2,5-dimethoxybenzaldehyde-1,4-dicarboxaldehyde, the product is an orange-red fluorescent powder (denoted as: CPTDD-TPA-OCH3 material).
[0015] Preferably, in step S1, the concentration of the aldehyde monomer in the mixed solution is 0.14-0.20 mmol / mL, and the concentration of CPTDD in the mixed solution is 0.014-0.02 mmol / mL. Preferably, the concentration of the aldehyde monomer in the mixed solution is 0.15 mmol / mL, and the concentration of CPTDD in the mixed solution is 0.015 mmol / mL.
[0016] Preferably, in S1, the mixed solvent is a mixture of mesitylene and 1,4-dioxane in a volume ratio of 1:5.
[0017] Preferably, in S2, the acid solution used as a catalyst is a 4M acetic acid solution, and the alkaline solution used as a catalyst is a 4M sodium hydroxide solution; the amount of acid solution or alkaline solution added is 0.2-0.25 times the volume of the mixed solution in S1.
[0018] Preferably, in S2, the reaction conditions are: under vacuum and oxygen-free conditions, the reaction is carried out at 120°C for 72 hours; after the reactor is cooled to room temperature, the precipitate is obtained by centrifugation at 10,000 rpm.
[0019] Preferably, in S3, the adsorbed impurities include the aldehyde monomer, CPTDD, solvent impurities, and intermediate products.
[0020] Preferably, in S3, the drying is performed in an oven at 60°C.
[0021] Preferably, sp is prepared in the laboratory. 2When using c-covalent organic framework materials, the reaction is carried out in a Schlenk tube. The mixed solution is transferred into the Schlenk tube and the catalyst is added before sealing. The Schlenk tube is then frozen, degassed, and thawed in liquid nitrogen. This process is repeated three times to remove all oxygen and ensure that the condensation reaction is carried out under vacuum.
[0022] (III) Beneficial Effects
[0023] The technical advantages of this invention are as follows:
[0024] This invention uses 1,3,5-tris(4-cyanomethylbenzene)benzene (CPTDD) as a triangularly symmetrical linker and condenses it with three aldehyde monomers—2,5-divinyl-1,4-phenylenedialdehyde (TPA-CH=CH2), terephthalaldehyde (TPA), and 2,5-dimethoxyphenyl-1,4-dicarboxaldehyde (TPA-OCH3)—to form a two-dimensional honeycomb polymer, successively yielding three sps: green, pale yellow, and orange-red. 2 c-covalent organic framework materials. This invention mainly utilizes the different side chains of the aldehyde monomers to prepare three sps materials emitting different fluorescence through side chain modulation. 2 c-covalent organic framework materials. Attached Figure Description
[0025] Figure 1 There are three types of SP. 2 Scanning electron microscope images of c-covalent organic framework materials (CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3).
[0026] Figure 2 There are three types of SP. 2 X-ray diffraction patterns of c-covalent organic framework materials (CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3) and Fourier transform infrared spectrum of product CPTDD-TPA-CH=CH2.
[0027] Figure 3 There are three types of SP. 2 Pore size distribution of c-covalent organic framework materials (CPTDD-TPA-CH=CH2, CPTDD-TPA and CPTDD-TPA-OCH3) calculated by N2 adsorption / desorption isotherm method.
[0028] Figure 4 For three types of sp 2 Fluorescence emission patterns of c-covalent organic framework materials (CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3) in aqueous solution and solid state. Detailed Implementation
[0029] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
[0030] Example 1
[0031] The product prepared in this embodiment is a two-dimensional honeycomb polymer composed of structural units as shown in I, where R is -CH=CH2, named CPTDD-TPA-CH=CH2. The preparation method is as follows:
[0032] (1) 2,5-Divinyl-1,4-phenylenedialdehyde (TPA-CH=CH2) and 1,3,5-tris(4-cyanomethylbenzene)benzene (CPTDD) were dissolved in a mixed solvent of mesitylene / 1,4-dioxane = 1:5, and ultrasonically mixed to obtain a mixed solution. In the mixed solution, the concentration of TPA-CH=CH2 was 0.15 mmol / mL, and the concentration of CPTDD was 0.015 mmol / mL.
[0033] (2) Transfer the mixed solution into a Schlenk tube, add 4M NaOH solution as a catalyst to the mixed solution and then seal it; perform freezing-degassing-thawing in liquid nitrogen, repeat the operation three times to remove oxygen, and react at 120°C under vacuum for 72 hours; after the reaction, cool to room temperature and centrifuge at 10,000 rpm to obtain the precipitate.
[0034] (3) The precipitate was washed five times with DMF and ethanol to remove unreacted monomers and impurities, dried in an oven at 60°C, and ground in an agate mortar to obtain green fluorescent powder.
[0035] Example 2
[0036] The product prepared in this embodiment is a two-dimensional honeycomb polymer composed of structural units as shown in I and where R is -H, named CPTDD-TPA. The preparation method is as follows:
[0037] (1) Terephthalaldehyde (TPA) and 1,3,5-tris(4-cyanomethylbenzene)benzene (CPTDD) were dissolved in a mixed solvent of mesitylene / 1,4-dioxane = 1:4.5, and the mixture was ultrasonically mixed to obtain a mixed solution. In the mixed solution, the concentration of TPA was 0.16 mmol / mL and the concentration of CPTDD was 0.014 mmol / mL.
[0038] (2) Transfer the mixed solution into a Schlenk tube, add 4M NaOH solution as a catalyst to the mixed solution and then seal it; perform freezing-degassing-thawing in liquid nitrogen, repeat the operation three times to remove oxygen, and react at 118°C under vacuum for 75 hours; after the reaction, cool to room temperature and centrifuge at 10,000 rpm to obtain the precipitate.
[0039] (3) The precipitate was washed five times with DMF and ethanol to remove unreacted monomers and impurities, dried in an oven at 60°C, and ground in an agate mortar to obtain a pale yellow fluorescent powder.
[0040] Example 3
[0041] The product prepared in this embodiment is a two-dimensional honeycomb polymer composed of structural units as shown in I, with R being -OCH3, named CPTDD-TPA-OCH3. The preparation method is as follows:
[0042] (1) 2,5-Dimethoxybenzene-1,4-dicarboxaldehyde (TPA-OCH3) and 1,3,5-tris(4-cyanomethylbenzene)benzene (CPTDD) were dissolved in a mixed solvent of mesitylene / 1,4-dioxane = 1:5.2, and the mixture was ultrasonically mixed to obtain a mixed solution. In the mixed solution, the concentration of TPA-OCH3 was 0.155 mmol / mL, and the concentration of CPTDD was 0.016 mmol / mL.
[0043] (2) Transfer the mixed solution into a Schlenk tube, add 4M NaOH solution as a catalyst to the mixed solution and then seal it; freeze-degas-thaw in liquid nitrogen, repeat the operation three times to remove oxygen, and react at 122℃ under vacuum for 70h; after the reaction, cool to room temperature and centrifuge at 10000rpm to obtain the precipitate.
[0044] (3) The precipitate was washed five times with DMF and ethanol to remove unreacted monomers and impurities, dried in an oven at 60°C, and ground in an agate mortar to obtain an orange-red fluorescent powder.
[0045] The three sp3 compounds, CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3, prepared in Examples 1-3, were compared. 2 The morphology of c-covalent organic framework materials was observed using scanning electron microscopy, and the results are as follows: Figure 1 As shown in the figure, a) is a 15000x SEM image, b) is a 15000x SEM image, and c) is a 20000x SEM image. (From...) Figure 1 It can be seen that CPTDD-TPA-CH=CH2 has a wrinkled two-dimensional lamellar structure; CPTDD-TPA has a small circular plate morphology; and CPTDD-TPA-OCH3 has a short rod shape.
[0046] like Figure 2 The images show three sp3 formulations prepared in Examples 1-3: CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3. 2 X-ray diffraction patterns of c-covalent organic framework materials and Fourier transform infrared (FTIR) patterns of CPTDD-TPA-CH=CH2. In the figures, a) corresponds to the X-ray diffraction pattern of CPTDD-TPA-CH=CH2, b) to CPTDD-TPA, c) to CPTDD-TPA-OCH3, d) to CPTDD-TPA-CH=CH2 and its corresponding monomers, e) to CPTDD-TPA and its corresponding monomers, and f) to CPTDD-TPA-OCH3 and its corresponding monomers. Figure 2 The AC values show that CPTDD-TPA-CH=CH2 and CPTDD-TPA exhibit a broad diffraction peak around 24°, indicating poor crystallinity. CPTDD-TPA-OCH3 shows sharp peaks at 2.82° (100 crystal plane) and 5.68° (200 crystal plane), indicating that CPTDD-TPA-OCH3 has good crystallinity. Figure 2 df shows that the stretching vibration peaks corresponding to the C=O and CH groups in the aldehyde monomer almost disappear; in CPTDD, the 2250 cm⁻¹ peak... -1 The C≡N stretching vibration shifted to 2212 cm. -1 The left and right positions indicate the successful synthesis of COFs.
[0047] like Figure 3 The images show three sp3 formulations prepared in Examples 1-3: CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3. 2 Pore size distribution diagrams of c-covalent organic framework materials calculated using the N2 adsorption / desorption isotherm method. Figure a) shows the pore size distribution of material CPTDD-TPA-CH=CH2, b) shows the pore size distribution of material CPTDD-TPA, and c) shows the pore size distribution of material CPTDD-TPA-OCH3. Figure 3 It can be seen that the pore sizes of CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3 are approximately 3.311 nm, 3.315 nm, and 3.135 nm, respectively, indicating that the introduction of side chains has caused the pore size to be reduced to a certain extent.
[0048] like Figure 4The images show three sp3 formulations prepared in Examples 1-3: CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3. 2 c-Fluorescence emission diagrams of covalent organic framework materials in aqueous solution and solid state. Figure a) shows the fluorescence emission diagrams of the three materials in solid state; the leftmost curve corresponds to CPTDD-TPA-CH=CH2, the middle curve to CPTDD-TPA, and the rightmost curve to CPTDD-TPA-OCH3. Figure b) shows the fluorescence emission diagrams of the three materials in aqueous solution; the leftmost curve corresponds to CPTDD-TPA-CH=CH2, the middle curve to CPTDD-TPA, and the rightmost curve to CPTDD-TPA-OCH3. Figure 4 It can be seen that the fluorescence emission peak positions of CPTDD-TPA-CH=CH2, CPTDD-TPA, and CPTDD-TPA-OCH3 in the solid state have a similar trend to those in the aqueous solution, all showing a change from green to orange-red, which proves that the side chain can regulate the fluorescence color of COF.
[0049] This invention uses 1,3,5-tris(4-cyanomethylbenzene)benzene (CPTDD) as a trigonal symmetrical linker and condenses it with three aldehyde monomers—2,5-divinyl-1,4-phenylenedialdehyde (TPA-CH=CH2), terephthalaldehyde (TPA), and 2,5-dimethoxybenzene-1,4-dicarboxaldehyde (TPA-OCH3)—to form two-dimensional honeycomb polymers, yielding three sps in green, pale yellow, and orange-red colors, respectively. 2 c-covalent organic framework materials enrich the variety of fluorescent covalent organic frameworks (LCOFs) and expand their applicable environments.
[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. sp 2 c-covalent organic framework material, which is a two-dimensional honeycomb polymer composed of the following structural units; the covalent organic framework material emits pale yellow or green fluorescence; ； in, R=H or CH=CH2; When R is H, the polymer emits a pale yellow fluorescence; when R is CH=CH2, the polymer emits a green fluorescence.
2. The sp as described in claim 1 2 The method for preparing c-covalent organic framework materials is characterized by... The preparation method of the covalent organic framework material is as follows: S1. Dissolve the aldehyde monomer and 1,3,5-tris(4-cyanomethylbenzene)benzene CPTDD in a mixed solvent of mesitylene and 1,4-dioxane, and mix ultrasonically to obtain a mixed solution; the aldehyde monomer is 2,5-divinyl-1,4-phenylenedialdehyde or terephthalaldehyde. S2. In an inert atmosphere or under vacuum, add an acid or alkali solution as a catalyst to the mixed solution to induce a condensation reaction between the aldehyde monomer and CPTDD. The reaction is carried out at 105 ℃-125 ℃ for 60-84 h. After the reactor is cooled to room temperature, the precipitate is obtained by centrifugation at 8000-12000 rpm. S3. The precipitate was centrifuged and washed sequentially with DMF and ethanol as detergents to remove adsorbed impurities. The precipitate was then dried and ground to obtain a powder. 2 c-covalent organic framework materials.
3. The preparation method according to claim 2, characterized in that, In S1, the concentration of the aldehyde monomer in the mixed solution is 0.14-0.20 mmol / mL, and the concentration of CPTDD in the mixed solution is 0.014-0.02 mmol / mL.
4. The preparation method according to claim 2, characterized in that, In S1, the mixed solvent is a mixture of mesitylene and 1,4-dioxane in a volume ratio of 1:
5.
5. The preparation method according to claim 2, characterized in that, In S2, the acid solution used as a catalyst is a 4M acetic acid solution, and the alkaline solution used as a catalyst is a 4M sodium hydroxide solution; the amount of acid solution or alkaline solution added is 0.2-0.25 times the volume of the mixed solution in S1.
6. The preparation method according to claim 2, characterized in that, In S2, the reaction conditions were as follows: under vacuum and oxygen-free conditions, the reaction was carried out at 120 °C for 72 h; after the reactor was cooled to room temperature, the precipitate was obtained by centrifugation at 10,000 rpm.
7. The preparation method according to claim 2, characterized in that, In S3, the adsorbed impurities include the aldehyde monomer, CPTDD, solvent impurities, and intermediate products.
8. The preparation method according to claim 2, characterized in that, In S3, the drying is performed in an oven at 60°C.
9. The preparation method according to claim 2, characterized in that, Preparation of sp in the laboratory 2 When using c-covalent organic framework materials, the reaction is carried out in a Schlenk tube. The mixed solution is transferred into the Schlenk tube and the catalyst is added before sealing. The Schlenk tube is then frozen, degassed, and thawed in liquid nitrogen. This process is repeated three times to remove all oxygen and ensure that the condensation reaction is carried out under vacuum.