Mesoporous covalent organic framework-anchored single-atom copper catalysts, methods of making and applications thereof

Abstract

The application provides a mesoporous covalent organic framework anchored single-atom copper catalyst and a preparation method and application thereof, the catalyst is prepared by taking a mesoporous covalent organic framework material PyT-Phen-COF or PyT-Bpy-COF as a carrier and loading copper single atoms on the carrier; and the covalent organic framework material is synthesized by reacting 2,4,6-tris(4-aminophenyl)-1,3,5-triazine with 4,4'-(pyridine-2,6-diyl)dibenzaldehyde or 4,4'-(pyridine-3,5-diyl)dibenzaldehyde. The application also provides a light-driven continuous flow system which is composed of an integrated multi-channel tubular reactor module and a photocatalytic membrane. The catalyst of the mesoporous covalent organic framework anchored single-atom copper synthesized by the application is applied to the light-driven continuous flow system, and can efficiently catalyze the carboxylation and cyclization reaction of CO2 and propargylamine to generate oxazolidinone compounds without an additional alkaline cocatalyst.

Description

Technical Field

[0001] This invention belongs to the field of catalyst synthesis and application, specifically relating to a mesoporous covalent organic framework anchored single-atom copper catalyst, its preparation method, and its application. Background Technology

[0002] Converting carbon dioxide (CO2) into value-added chemicals is an effective strategy for mitigating global climate change caused by excessive CO2 emissions. To date, various attractive studies have been conducted worldwide, such as using CO2 as a C1 source to obtain carbonylated products, including acids, cyclic carbonates, and polycarbonates. Among various CO2 chemical fixation methods, the reaction of propyneamine with CO2 carboxylation cyclization to produce oxazolidinones is particularly attractive due to its significant pharmaceutical value and high global market demand.

[0003] Recent studies have shown that low-valent copper (Cu) is an excellent catalyst for the carboxylation-cyclization reaction of propyneamine with CO2. However, low-valent Cu is readily oxidized to a higher valence state in air, leading to a decrease in catalytic activity, and controlling the oxidation state of Cu in heterocomposite materials is also quite challenging.

[0004] Furthermore, most current catalysts typically require additional bases (such as DBU, DABCO, and Et3N) as co-catalysts to achieve substrate deprotonation and CO2 activation under harsh conditions such as high pressure and / or high temperature. The use of these environmentally unfriendly bases reduces economic efficiency and complicates the product purification process. Most importantly, strong bases also affect the stability of heterogeneous catalysts, severely hindering their practicality.

[0005] Therefore, how to develop a robust catalyst that can control the specific oxidation state of the active site and achieve the carboxylation-cyclization reaction of base-free propyneamine with CO2 in a green and sustainable manner remains a highly anticipated but unsolved challenge. Summary of the Invention

[0006] The purpose of this invention is to provide a mesoporous covalent organic framework-anchored single-atom copper catalyst, its preparation method, and a light-driven continuous flow system composed of an integrated multi-channel tubular reactor module and a photocatalytic membrane. Applying the catalyst of this invention to a light-driven continuous flow system allows for efficient catalysis of the carboxylation and cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds without the need for an additional alkaline co-catalyst.

[0007] The present invention adopts the following technical solution: A catalyst for anchoring single-atom copper in a mesoporous covalent organic framework, the catalyst being represented by Cu-PyT-Phen-COF or Cu-PyT-Bpy-COF, is prepared by loading single copper atoms onto a mesoporous covalent organic framework material PyT-Phen-COF or PyT-Bpy-COF as a support. The PyT-Phen-COF material is synthesized by reacting 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde with 1,3,6,8-tetra-(p-aminophenyl)-pyrene; the PyT-Bpy-COF material is synthesized by reacting 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde with 1,3,6,8-tetra-(p-aminophenyl)-pyrene.

[0008] The aforementioned mesoporous covalent organic framework-anchored single-atom copper catalyst was prepared by the following method: (a) Add 1,3,6,8-tetra-(p-aminophenyl)-pyrene and 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde or 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde to a vacuum reaction vessel, add an organic solvent and ultrasonically disperse, mix evenly, add acetic acid solution, then vacuum seal the reaction system and react at 80~160 ℃ for 2~7 days to obtain mesoporous covalent organic framework materials PyT-Phen-COF or PyT-Bpy-COF; (b) The mesoporous covalent organic framework material PyT-Phen-COF or PyT-Bpy-COF and copper salt are added to an organic solvent and placed in an oil bath reactor at 20-100°C. The mixture is heated and stirred for 20-28 hours under an inert gas atmosphere. After cooling to room temperature, the precipitate is collected by filtration, washed, and vacuum dried to obtain the catalyst Cu-PyT-Phen-COF or Cu-PyT-Bpy-COF.

[0009] Furthermore, in step (a), the vacuum reaction vessel is a thick-walled pressure-resistant bottle with a vacuum shut-off valve, and the molar ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde or 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde is 1:0.5~3, preferably 1:2.

[0010] Further, in step (a), the initial concentration of 1,3,6,8-tetra-(p-aminophenyl)-pyrene, 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde or 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde is 1~100 g / L, preferably 10~40 g / L.

[0011] Further, in step (a), the organic solvent is any two of the following selected organic solvents mixed in a volume ratio of 1:0.5 to 3:1:0.5:3:2 ...

[0012] Further, in step (a), the concentration of the acetic acid solution is 3-9 mol / L, and the amount used is 0.05-0.5 times the total amount of organic solvent. Preferably, the concentration of the acetic acid solution is 6 mol / L, and the amount used is 0.1 times the total amount of organic solvent.

[0013] Furthermore, in step (a), the stirring rate of the reaction process is 0 to 1000 rpm, preferably 600 rpm.

[0014] Further, in step (b), the copper salt is any one of copper nitrate, copper acetate, copper chloride, copper sulfate, or copper carbonate, wherein the amount of copper salt used is 0.01-3 times the mass of the covalent organic framework material, preferably 0.2 times. More preferably, the copper salt is copper acetate.

[0015] Furthermore, in step (b), the organic solvent is methanol.

[0016] The above-mentioned mesoporous covalent organic framework-anchored single-atom copper catalyst is used in the catalytic carboxylation and cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds.

[0017] This invention also provides a light-driven continuous flow system, which consists of an integrated multi-channel tubular reactor module and a photocatalytic membrane. The specific construction method is as follows: (a) Preparation and fixation of photocatalyst film: First, the photocatalyst film is prepared by coating method. The prepared photocatalyst film is wrapped on a quartz rod, and a small section of polytetrafluoroethylene (PTFE) tube is added to both ends of the rod to fix the catalyst film. The photocatalyst is Cu-PyT-Phen-COF or Cu-PyT-Bpy-COF. (b) Assembling a single-channel reactor: A glass rod with a photocatalyst membrane is placed inside a quartz tube to form a single-channel reactor. Multiple single-channel reactors are prepared by repeating this method. (c) Connecting the multi-channel reactor module: PTFE pipes are connected to multiple single-channel reactors using a polytetrafluoroethylene (PTFE) reducing straight-through pipe, and simultaneously connected to a peristaltic pump to form a multi-channel tubular reactor module.

[0018] Furthermore, the operation of preparing the photocatalyst film by coating method is as follows: the photocatalyst and polyvinylidene fluoride (PVDF) powder are dispersed in 1-methyl-2-pyridone (NMP) and ultrasonically stirred at room temperature to obtain a uniform slurry; then, the slurry is coated on aluminum foil using a four-sided coating tool and dried to obtain the photocatalyst film.

[0019] Furthermore, when preparing the photocatalyst film, the mass ratio of the photocatalyst to the polyvinylidene fluoride (PVDF) powder is 1:0.01~1, with the optimal mass ratio being 1:0.1; the initial concentration of the photocatalyst is 0.1~100g / L, preferably 1g / L; and the thickness of the aluminum foil is 0.01mm~2mm, preferably 0.05mm.

[0020] Furthermore, the length and width of the photocatalyst film are the same as the length and diameter of the quartz rod, respectively.

[0021] Furthermore, the inner diameter of the polytetrafluoroethylene tube is 0.1mm to 10mm, preferably 1mm, and the thickness is 0.1mm to 10mm, preferably 1mm.

[0022] Furthermore, when assembling the single-channel reactor, the wall thickness of the quartz tube is 0.1mm to 10mm, preferably 1mm; the inner diameter is 2mm larger than the diameter of the glass rod with the photocatalyst film.

[0023] Furthermore, when assembling the multi-channel tubular reactor module, the diameter-adjustable straight-through specification of the PTFE tube is consistent with the outer diameter of the quartz tube and the PTFE tube, respectively.

[0024] The above-mentioned light-driven continuous flow system is used in the catalytic carboxylation and cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds.

[0025] In application, the multi-channel tubular reactor is filled with CO2 through displacement, and the reaction mixture is injected into the multi-channel tubular reactor module via a peristaltic pump and then illuminated to achieve continuous cyclic catalysis. The light source for illumination can be an LED lamp, a xenon lamp, or natural light.

[0026] Furthermore, the solvent for the carboxylation-cyclization reaction is methanol, the reaction gas is carbon dioxide, the reaction pressure is atmospheric pressure, the reaction temperature is room temperature, and the substrate is acetylacetylpropylamine.

[0027] The beneficial effects of this invention are as follows: 1. The mesoporous covalent organic framework-anchored single-atom copper catalyst provided by this invention exhibits excellent catalytic activity and selectivity in the baseless carboxylation cyclization reaction of propyneamine and carbon dioxide, with a target product yield as high as 99.9%; and it maintains high catalytic performance in multiple cycle experiments, showing good stability and durability, and is suitable for long-term continuous operation.

[0028] 2. The photocatalyst membrane in the light-driven continuous flow system provided by this invention promotes the mass transfer of reactants and effectively utilizes active sites. The multi-channel tubular reactor module has a simple and compact structure, readily available materials, low space requirements and high utilization rate, is easy to install, and its inner diameter, wall thickness and tube length are adjustable. At the same time, the photocatalyst membrane almost completely occupies the volume of the reactor, which can ensure the full absorption of incident light, thereby significantly shortening the reaction time and improving production efficiency. It is especially suitable for large-scale production to realize the large-scale photothermal carboxylation and cyclization of CO2.

[0029] 3. When the mesoporous covalent organic framework-anchored single-atom copper catalyst synthesized in this invention is applied to a light-driven continuous flow system, it can efficiently catalyze the carboxylation and cyclization reaction of CO2 with propargylamine to generate oxazolidinone compounds without the need for additional alkaline co-catalysts. Attached Figure Description

[0030] Figure 1 This is a schematic diagram illustrating the preparation of the catalyst materials in Examples 1-4.

[0031] Figure 2 The image shows the infrared spectra of the raw materials and the prepared PyT-Phen-COF in Example 1.

[0032] Figure 3 The nitrogen isothermal adsorption-desorption curve of PyT-Phen-COF prepared in Example 1 is shown.

[0033] Figure 4 The image shows the pore size distribution of PyT-Phen-COF prepared in Example 1.

[0034] Figure 5 The image shows the powder X-ray diffraction pattern of PyT-Phen-COF prepared in Example 1.

[0035] Figure 6 The image shows the infrared spectra of the raw materials and the prepared PyT-Bpy-COF in Example 2.

[0036] Figure 7 The nitrogen isothermal adsorption-desorption curve of PyT-Bpy-COF prepared in Example 2 is shown.

[0037] Figure 8 The image shows the pore size distribution of PyT-Bpy-COF prepared in Example 2.

[0038] Figure 9 The image shows the powder X-ray diffraction pattern of PyT-Bpy-COF prepared in Example 2.

[0039] Figure 10The image shows the powder X-ray diffraction pattern of Cu-PyT-Phen-COF prepared in Example 3.

[0040] Figure 11 The image shows the powder X-ray diffraction pattern of Cu-PyT-Bpy-COF prepared in Example 4.

[0041] Figure 12 This is a schematic diagram of the single-channel tubular reactor module device prepared in Example 6. In the diagram, 1 is a photocatalyst membrane, 2 is a quartz tube, and 3 is a polytetrafluoroethylene tube.

[0042] Figure 13 This is a schematic diagram of the multi-channel tubular reactor module device prepared in Example 6. 1. Light source, 2. Balloon, 3. Polytetrafluoroethylene tube, 4. Round-bottom flask, 5. Peristaltic pump. Detailed Implementation

[0043] The present invention will be further described below with reference to the embodiments. The embodiments described below are for illustration only and do not limit the scope of protection of the present invention in any way.

[0044] The processes and methods not described in detail in the following embodiments are conventional methods known in the art. All reagents used in the embodiments are analytically pure or chemically pure, and are commercially available or prepared by methods well known to those skilled in the art. The following embodiments all achieve the objectives of the present invention.

[0045] Unless otherwise specified, the two mesoporous covalent organic framework-anchored single-atom copper catalysts prepared by the method described in this invention are named Cu-PyT-Phen-COF and Cu-PyT-Bpy-COF, respectively, in the specification.

[0046] like Figure 1 The diagram shows the preparation of the catalysts PyT-Phen-COF, PyT-Bpy-COF, Cu-PyT-Phen-COF, and Cu-PyT-Bpy-COF described in Examples 1-4. The specific preparation process for each catalyst is as follows.

[0047] Example 1 1,3,6,8-tetra-(p-aminophenyl)pyrene (56.7 mg, 0.1 mmol) and 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde (77.7 mg, 0.2 mmol) were added to a thick-walled pressure tube (15 mL) equipped with a vacuum switch. A mixed solution of mesitylene and 1,4-dioxane (6 mL, v / v ratio 1:1) was then added and ultrasonically dispersed for 30 min. Subsequently, 0.6 mL of 6 M acetic acid (AcOH) was added to the mixture, and ultrasonic dispersion was repeated. After three freeze-thaw cycles for degassing, the mixture was heated and stirred at 120°C for 3 days. After cooling to room temperature, the precipitate was collected by filtration and washed successively with excess methanol, tetrahydrofuran, and acetone. Finally, it was dried under vacuum at 60°C for 24 h to obtain PyT-Phen-COF in 90% yield.

[0048] like Figure 2 The image shows the infrared spectra of the prepared PyT-Phen-COF and its raw materials. As can be seen from the figure, the characteristic amino group (NH) of the monomer is in the range of 3200~3500 cm⁻¹. -1 ) and aldehyde group (at 1680cm -1 The stretching vibration almost completely disappeared at 1620cm. -1 A new (C=N) stretching vibration peak was observed, indicating that the catalyst was successfully synthesized.

[0049] like Figure 3 The figure shows the nitrogen isotherm adsorption-desorption curves of the prepared PyT-Phen-COF. It can be seen that PyT-Phen-COF exhibits a type IV reversible isotherm, and the material has a specific surface area of ​​975.5 m². 2 g -1 .

[0050] like Figure 4 The image shows the pore size distribution of the prepared PyT-Phen-COF. It can be seen that the pore size of PyT-Phen-COF is mainly distributed at 3.3 nm, which conforms to mesoporous characteristics.

[0051] like Figure 5 The image shows the powder X-ray diffraction pattern of the prepared PyT-Phen-COF. It can be seen that PyT-Phen-COF exhibits high crystallinity and a 2D layered structure with AA stacking.

[0052] Example 2 1,3,6,8-tetra-(p-aminophenyl)pyrene (56.7 mg, 0.1 mmol) and 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde (72.8 mg, 0.2 mmol) were added to a thick-walled pressure tube (15 mL) equipped with a vacuum switch. A mixed solution of mesitylene and benzyl alcohol (6 mL, v / v = 2:1) was then added, and the mixture was ultrasonically dispersed for 30 min. Subsequently, 0.6 mL of 6 M acetic acid (AcOH) was added to the mixture, and the mixture was ultrasonically dispersed again. After three freeze-thaw cycles for degassing, the mixture was heated and stirred at 120°C for 3 days. After cooling to room temperature, the precipitate was collected by filtration and washed successively with excess methanol, tetrahydrofuran, and acetone. Finally, it was dried under vacuum at 60°C for 24 h to obtain PyT-Bpy-COF in 87% yield.

[0053] like Figure 6 The image shows the infrared spectra of the prepared PyT-Bpy-COF and its raw materials. As can be seen from the figure, the characteristic amino group (NH) of the monomer is in the range of 3200~3500 cm⁻¹. -1 ) and aldehyde group (at 1680cm -1 The stretching vibration almost completely disappeared at 1620cm. -1 A new (C=N) stretching vibration peak was observed, indicating that the catalyst was successfully synthesized.

[0054] like Figure 7 The figure shows the nitrogen isotherm adsorption-desorption curves of the prepared PyT-Bpy-COF. It can be seen that PyT-Phen-COF exhibits a type IV reversible isotherm, and the material has a specific surface area of ​​114.1 m². 2 g -1 .

[0055] like Figure 8 The image shows the pore size distribution of the prepared PyT-Bpy-COF. It can be seen that the pore size of PyT-Bpy-COF is mainly distributed at 3.3 nm, which is consistent with mesoporous characteristics.

[0056] like Figure 9 The image shows the powder X-ray diffraction pattern of the prepared PyT-Bpy-COF. It can be seen that PyT-Bpy-COF exhibits high crystallinity and a 2D layered structure with AA stacking.

[0057] Example 3 PyT-Phen-COF (50.0 mg) and Cu(OAc)2⋅H2O (10.0 mg) were added to 15 mL of methanol and placed in an oil bath reactor at 80°C. The mixture was heated and stirred for 12 hours under a nitrogen atmosphere. After cooling to room temperature, the precipitate was collected by filtration and washed successively with methanol, tetrahydrofuran, and acetone. The precipitate was then dried overnight under vacuum at 60°C to obtain the catalyst Cu-PyT-Phen-COF.

[0058] like Figure 10 The image shows the powder X-ray diffraction pattern of Cu-PyT-Phen-COF prepared in Example 3. It can be seen that the powder X-ray diffraction pattern of Cu-PyT-Phen-COF does not show significant changes compared to PyT-Phen-COF, indicating that the original COF structure remains unchanged after metal loading.

[0059] Example 4 PyT-Bpy-COF (50.0 mg) and Cu(OAc)₂⋅H₂O (10.0 mg) were added to 15 mL of methanol, sonicated, and then refluxed in an oil bath at 20-70°C for 20-28 h. The mixture was then stirred for 12 h under a nitrogen atmosphere at 80°C. After cooling to room temperature, the precipitate was collected by filtration, washed successively with methanol, tetrahydrofuran, and acetone, and dried overnight under vacuum at 60°C to obtain Cu-PyT-Bpy-COF.

[0060] like Figure 11 The image shows the powder X-ray diffraction pattern of Cu-PyT-Bpy-COF prepared in Example 4. It can be seen that the powder X-ray diffraction pattern of Cu-PyT-Bpy-COF does not show significant changes compared to PyT-Bpy-COF, indicating that the original COF structure remains unchanged after metal loading.

[0061] Example 5 In a self-designed 70 mL quartz reactor, four catalysts (10 mg each) were added to mixtures of propargylamine (0.5 mmol) and methanol (5.0 mL), respectively. A blank control was prepared using only propargylamine (0.5 mmol) and methanol (5.0 mL). The quartz reactor was then sealed with a quartz glass top, purified, and filled with 99.999% CO2. The reaction temperature was maintained at 25 °C. After irradiating the reaction mixture with a 60 W LED light source at room temperature for 1 h, the reaction mixture was qualitatively analyzed using gas chromatography (GC, Agilent 7820A). To obtain pure products, the crude product was concentrated and purified by column chromatography. All purified products were subjected to... 1 H NMR and 13C10 NMR identification. The catalytic performance results of different catalysts are shown in Table 1.

[0062] Table 1 Comparison of catalytic performance of different catalysts Example 6 To achieve large-scale application of CO2 photothermal carboxylation and cyclization, a light-driven continuous flow system consisting of an integrated multi-channel tubular reactor module and a photocatalytic membrane was constructed.

[0063] First, 50 mg of Cu-PyT-Phen-COF catalyst and 5 mg of polyvinylidene fluoride powder were uniformly dispersed in 1-methyl-2-pyridone (1 ml) and ultrasonically stirred at room temperature for 20 min to obtain a homogeneous slurry. Then, the slurry was coated onto a 0.05 mm thick aluminum foil using a four-sided coating tool. Finally, it was dried at 80 °C to obtain a photocatalyst film. The prepared photocatalyst film was cut into rectangles 200 mm long and 6 mm wide, and then wrapped around a quartz rod with a diameter of 6 mm and a length of 200 mm. 10 mm polytetrafluoroethylene (PTFE) tubes were added to both ends of the rod to fix the catalyst film.

[0064] A single-channel reactor was obtained by placing a glass rod with a photocatalyst film into a quartz tube with an inner diameter of 8 mm and a length of 200 mm. This method was repeated to prepare 5 single-channel reactors. A polytetrafluoroethylene (PTFE) reducing tube was used to connect the PTFE tube to the 5 prepared single-channel reactors, and simultaneously connected to a peristaltic pump to form the final multi-channel tubular reactor module.

[0065] Figure 12 This is a schematic diagram of the single-channel tubular reactor module device prepared in Example 6. As shown in the figure, the device consists of a photocatalyst membrane 1, a quartz tube 2, and a polytetrafluoroethylene tube 3.

[0066] Figure 13 This is a diagram of the multi-channel tubular reactor module device prepared in Example 6. As shown in the figure, the device includes a light source 1, a balloon 2, and multiple single-channel reactors connected to a round-bottom flask 4 via polytetrafluoroethylene tubes 3, and is also connected to a peristaltic pump 5.

[0067] Example 7 A 250 mL three-necked flask was filled with 10 mol of different amounts of propargylamine and 100 mL of methanol. One end of the flask was connected to a CO2 balloon, and the other end was connected to the inlet and outlet of the multi-channel tubular reactor module of the light-driven continuous flow system prepared in Example 6. Before the reaction, to remove residual air, CO2 was repeatedly purged and purged, and finally, CO2 was blown into the reaction system. The reaction mixture was injected into the tubular reactor module using a peristaltic pump, and the reaction module was simultaneously irradiated with an LED panel for 8 hours. During the reaction, the reaction mixture was qualitatively analyzed using gas chromatography (GC, Agilent 7820A). After the reaction, the solvent was removed directly by vacuum distillation, and all products were... 1 H NMR and 13 C10 NMR identification. The results are shown in Table 2.

[0068] Table 2 Catalytic performance of Cu-PyT-Phen-COF catalysts for different derivatives in light-driven continuous flow systems Example 8 N-phenylmethylprop-2-yn-1-amine (10 mmol, 1.45 g) and 100 mL of methanol were added to a 250 mL three-necked flask. One end of the flask was connected to a CO2 balloon, and the other end was connected to the inlet and outlet of the multi-channel tubular reactor module of the light-driven continuous flow system prepared in Example 6. Before the reaction, residual air was removed by repeated purging and charging with CO2, and finally, CO2 was blown into the reaction system. The reaction mixture was injected into the multi-channel tubular reactor module using a peristaltic pump, and the photothermal catalytic reaction was carried out under outdoor sunlight from May 13th to 15th, 2024, from 08:00 to 16:00 each day, with a sunlight intensity between 53 and 112 mW / cm². The results showed that after 3 days (24 hours in total), a high-purity target product 2a (as shown in Formula I) was obtained, with a yield close to 100%. After the reaction, the solvent was removed directly from the mixture by vacuum distillation, and the product was... 1 H NMR and 13 C NMR identification.

Claims

1. A mesoporous covalent organic framework-anchored single-atom copper catalyst for the alkali-free catalytic carboxylation-cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds, characterized in that, The catalyst is represented by Cu-PyT-Phen-COF or Cu-PyT-Bpy-COF, which is prepared by loading copper single atoms onto the mesoporous covalent organic framework material PyT-Phen-COF or PyT-Bpy-COF as a support. The PyT-Phen-COF material is synthesized by reacting 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde with 1,3,6,8-tetra-(p-aminophenyl)-pyrene; the PyT-Bpy-COF material is synthesized by reacting 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde with 1,3,6,8-tetra-(p-aminophenyl)-pyrene.

2. A method for preparing a catalyst with a mesoporous covalent organic framework anchored to a single atom of copper as described in claim 1, characterized in that, Includes the following steps: (a) Add 1,3,6,8-tetra-(p-aminophenyl)-pyrene and 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde or 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde to a vacuum reaction vessel, add an organic solvent and ultrasonically disperse, mix evenly, add acetic acid solution, then vacuum seal the reaction system and react at 80~160 ℃ for 2~7 days to obtain mesoporous covalent organic framework materials PyT-Phen-COF or PyT-Bpy-COF; (b) The mesoporous covalent organic framework material PyT-Phen-COF or PyT-Bpy-COF and copper salt are added to an organic solvent and placed in an oil bath reactor at 20-100°C. The mixture is heated and stirred for 20-28 hours under an inert gas atmosphere. After cooling to room temperature, the precipitate is collected by filtration, washed, and vacuum dried to obtain the catalyst Cu-PyT-Phen-COF or Cu-PyT-Bpy-COF.

3. The method for preparing the catalyst with mesoporous covalent organic framework anchored single-atom copper according to claim 2, characterized in that, In step (a), the molar ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to 4,4'-(1,10-phenanthroline-3,8-diyl)dibenzaldehyde or 4,4'-([2,2'-bipyridine]-5,5'-diyl)dibenzaldehyde is 1:0.5~3; the concentration of the acetic acid solution is 3~9 mol / L, and the amount used is 0.05~0.5 times the total amount of organic solvent.

4. The method for preparing the catalyst with mesoporous covalent organic framework anchored single-atom copper according to claim 2, characterized in that, In step (b), the amount of copper salt used is 0.01-3 times the mass of the covalent organic framework material.

5. The method for preparing the catalyst with mesoporous covalent organic framework anchored single-atom copper according to claim 2, characterized in that, In step (a), the organic solvent is any two of the following: tert-butanol, benzyl alcohol, 1,4-dioxane, n-butanol, mesitylene, o-dichlorobenzene, or tetrahydrofuran, mixed in a volume ratio of 1:0.5 to 3.

6. The application of the mesoporous covalent organic framework-anchored single-atom copper catalyst of claim 1 or the mesoporous covalent organic framework-anchored single-atom copper catalyst prepared according to any one of claims 2 to 5 in catalyzing the carboxylation and cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds.

7. A light-driven continuous flow system for alkali-free catalytic carboxylation-cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds, characterized in that, The light-driven continuous flow system consists of an integrated multi-channel tubular reactor module and a photocatalytic membrane, and the construction method is as follows: (a) Preparation and fixation of photocatalyst film: First, the photocatalyst is prepared into a photocatalyst film by coating method. The prepared photocatalyst film is wrapped on a quartz rod, and a short section of polytetrafluoroethylene tube is added to both ends of the rod to fix the catalyst film. The photocatalyst is the mesoporous covalent organic framework anchored single-atom copper catalyst as described in claim 1. (b) Assembling a single-channel reactor: A glass rod with a photocatalyst membrane is placed in a quartz tube to form a single-channel reactor. This method is repeated to prepare multiple single-channel reactors. (c) Connecting the multi-channel reactor module: PTFE pipes are connected to multiple single-channel reactors using a polytetrafluoroethylene (PTFE) reducing straight-through pipe, and simultaneously connected to a peristaltic pump to form a multi-channel tubular reactor module.

8. The optically driven continuous flow system according to claim 7, characterized in that, The process of preparing a photocatalyst film by coating method is as follows: the photocatalyst and polyvinylidene fluoride powder are dispersed in 1-methyl-2-pyridone and ultrasonically stirred at room temperature to obtain a uniform slurry; then, the slurry is coated on aluminum foil with a four-sided coating tool and dried to obtain a photocatalyst film.

9. The application of the light-driven continuous flow system of claim 7 in catalyzing the carboxylation and cyclization reaction of propyneamine with CO2 to generate oxazolidinone compounds.

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