Preparation method of zinc coordination polymer and application thereof in catalysis of conversion of aryl-substituted ethylene into aryl carboxaldehyde / aryl ketone derivatives
The zinc coordination polymer catalyst prepared by the catalyst solves the problems of complex preparation process, expensive raw materials and environmental unfriendliness of aryl formaldehyde/aryl ketone derivatives in the existing technology, and realizes inexpensive and readily available highly selective catalytic conversion, which is suitable for large-scale production.
Patent Information
- Application Number
- CN202411191715.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2044-08-28
AI Technical Summary
Existing methods for preparing arylformaldehyde/aryl ketone derivatives are complex, use expensive raw materials, have poor reaction selectivity, and are environmentally unfriendly, which limits their application.
A zinc coordination polymer was prepared by reacting pyromellitic acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine and zinc nitrate hexahydrate in methanol and N,N-dimethylacetamide solution using a zinc coordination polymer as a catalyst. The zinc coordination polymer was then used to catalyze the conversion of aryl-substituted ethylene to aryl formaldehyde/aryl ketone derivatives.
It achieves catalytic conversion with inexpensive and readily available raw materials, high reaction selectivity, mild conditions, simple operation, and environmental friendliness. It has high catalytic activity and stability and is suitable for large-scale production.
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Figure CN119019703B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of catalyst technology, and particularly relates to a method for preparing a zinc coordination polymer and its application in the catalytic conversion of aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives. Background Technology
[0002] Arylformaldehyde / aryl ketone derivatives are a class of commonly used chemical raw materials and important intermediates in organic synthesis. Traditional methods for preparing arylformaldehyde include the hydrolysis of chlorinated aromatics, toluene oxidation, aryl methanol oxidation, hydrogenation reduction of arylformic acid, and indirect electro-oxidation. However, these methods have many drawbacks, such as complex synthesis processes, expensive initial raw materials, poor reaction selectivity and low efficiency, the need for inert gas protection, and environmental unfriendliness, thus limiting the further application of arylformaldehyde / aryl ketone derivatives.
[0003] Therefore, developing a method with inexpensive and readily available reaction raw materials, high reaction selectivity, mild reaction conditions, and environmental friendliness will have significant research and application value. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention proposes a method for preparing a zinc coordination polymer and its application in the catalytic conversion of aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives. This invention provides a novel zinc coordination polymer that can be used as a catalyst for the selective catalytic conversion of aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives. The method for selectively catalyzing the conversion of aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives using this novel zinc coordination polymer as a catalyst has the advantages of inexpensive and readily available reactants, high reaction selectivity, mild reaction conditions, ease of operation, and environmental friendliness.
[0005] To achieve the above objectives, the present invention provides the following technical solution:
[0006] One of the technical solutions of the present invention:
[0007] A method for preparing a zinc coordination polymer includes the following steps:
[0008] Tristyric acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine and zinc nitrate hexahydrate were dissolved in a mixed solution of methanol and N,N-dimethylacetamide and stirred until homogeneous to obtain a solution. The solution was heated at 90-110°C and cooled to room temperature to obtain pale yellow crystals, which are the zinc coordination polymer.
[0009] Preferably, in the method for preparing the zinc coordination polymer, the trimellitic acid... 2,4,6-Tris(4-pyridyl)-1,3,5-triazine The molar ratio of zinc nitrate hexahydrate to zinc nitrate is 1:1:2.
[0010] Preferably, in the method for preparing the zinc coordination polymer, the volume ratio of methanol to N,N-dimethylacetamide is 1:(3-3.5).
[0011] Preferably, in the method for preparing the zinc coordination polymer, the heating time is 48 to 72 hours, and the cooling rate is 10 to 15 °C / min.
[0012] The second technical solution of the present invention:
[0013] The present invention also provides a zinc coordination polymer prepared by the above method.
[0014] The zinc coordination polymer provided by this invention can be used as a green catalyst to directly convert aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives.
[0015] The third technical solution of the present invention:
[0016] The present invention also provides the application of the zinc coordination polymer in the catalytic conversion of aryl-substituted ethylene to aryl formaldehyde / aryl ketone derivatives (aryl formaldehyde or aryl ketone derivatives).
[0017] In the above-described applications of the present invention, the aryl-substituted ethylene includes styrene and its derivatives.
[0018] The fourth technical solution of the present invention:
[0019] This invention also provides a method for catalytically converting aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives. The aryl-substituted ethylene is dissolved in ethanol, and then the zinc coordination polymer and hydrogen peroxide are added. The resulting mixture is heated to 60°C. After the raw material (i.e., aryl-substituted ethylene) has reacted completely, ethyl acetate is added for extraction, and the solvent is dried to obtain a crude product. The crude product is then separated by column chromatography to obtain the aryl formaldehyde / aryl ketone derivative.
[0020] Preferably, in the method for catalytically converting aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives, the amount of zinc coordination polymer added is 0.1 mol% of the aryl-substituted ethylene, such that when the amount of aryl-substituted ethylene added is 1 mol, the amount of zinc coordination polymer added is 0.001 mol.
[0021] Preferably, in the method for catalytically converting aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives, the reaction time is 6 to 12 hours.
[0022] Preferably, in the method for catalytically converting aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives, the molar ratio of the aryl-substituted ethylene to the hydrogen peroxide is 1:3, and the mass fraction of the hydrogen peroxide is 30%.
[0023] Preferably, in the method for catalytically converting aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives, the eluent is petroleum ether and ethyl acetate, the volume ratio of petroleum ether to ethyl acetate is 1:0 to 20:1, and the volume of ethyl acetate is not 0.
[0024] More preferably, the general structural formula of aryl-substituted ethylene is: Where R 1 =H, 4-OMe, 4-Br or 4-F, R 2 =Ph or H, the reaction route for producing aryl formaldehyde or aryl ketone products is as follows:
[0025]
[0026] In the method of the present invention for catalytic conversion of aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives, the yield of aryl formaldehyde / aryl ketone derivatives is 91-97%.
[0027] Compared with the prior art, the present invention has the following advantages and technical effects:
[0028] (1) The method of the present invention has low requirements for synthesis equipment, is simple and convenient to operate, has readily available raw materials, is inexpensive, has mild reaction conditions, can be produced on a large scale, and produces zinc coordination polymer materials with high yield and good purity.
[0029] (2) The zinc coordination polymer prepared by the present invention has good chemical stability and thermal stability. It can be stably present for 24 hours in an aqueous solution with pH 2-12 and has a maximum heat resistance of 300℃.
[0030] (3) The zinc coordination polymer prepared by this invention has the characteristics of high conversion rate and high chemical stability as a catalyst. It has extremely high catalytic activity for the reaction of aryl-substituted ethylene to aryl formaldehyde / aryl ketone derivatives. Moreover, the amount used is low (only 0.1 mol%), the catalytic reaction conditions are mild and easy to operate, and it has good practical value and application prospects. Attached Figure Description
[0031] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:
[0032] Figure 1 This is an X-ray single-crystal structure diagram of the zinc coordination polymer prepared in Example 1 of the present invention;
[0033] Figure 2 This is a three-dimensional structural diagram of the zinc coordination polymer prepared in Example 1 of the present invention;
[0034] Figure 3 Thermogravimetric curve of the zinc coordination polymer obtained in Example 1 of this invention;
[0035] Figure 4 The XRD pattern of the zinc coordination polymer obtained in Example 1 of this invention;
[0036] Figure 5 The XRD patterns of the zinc coordination polymer obtained in Example 1 of this invention after being soaked in aqueous solutions at pH 2 and 12 for 24 hours are shown.
[0037] Figure 6 Thermogravimetric curve of the zinc coordination polymer obtained in Example 2 of this invention;
[0038] Figure 7 The XRD pattern of the zinc coordination polymer obtained in Example 2 of this invention;
[0039] Figure 8 This is a catalytic yield diagram of the zinc coordination polymer prepared in Example 2 of the present invention for the catalytic conversion of styrene to benzaldehyde and its recycling.
[0040] Figure 9 The XRD patterns of the zinc coordination polymer prepared in Example 2 of this invention before and after catalytic conversion of styrene to benzaldehyde and recycling are shown. Detailed Implementation
[0041] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.
[0042] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0043] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.
[0044] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.
[0045] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0046] All raw materials used in the embodiments of this invention were obtained through commercial purchase.
[0047] In the embodiments of the present invention, pyromellitic acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine, zinc nitrate hexahydrate, methanol, and N,N-dimethylacetamide were all of analytical grade. Aryl-substituted ethylene and hydrogen peroxide (30% by mass) were both of analytical grade. Ethanol, petroleum ether, and ethyl acetate were all of analytical grade.
[0048] In the embodiments of the present invention, unless otherwise specified, the room temperature is 25±2℃.
[0049] The technical solution of the present invention will be further illustrated by the following embodiments.
[0050] Example 1
[0051] A method for preparing a zinc coordination polymer:
[0052] 0.1 mmol of trimesic acid, 0.1 mmol of 2,4,6-tris(4-pyridyl)-1,3,5-triazine, and 0.2 mmol of zinc nitrate hexahydrate were added to a mixed solution containing 1 mL of methanol and 3 mL of N,N-dimethylacetamide. The mixture was stirred for 5 minutes at room temperature in air. The stirred solution was then transferred to a 15 mL Teflon autoclave and heated to 100 °C in an oven for 48 hours. After the reaction was completed, the temperature was lowered to room temperature at a rate of 10 °C / h to obtain pale yellow crystals. After filtration, washing with methanol, and vacuum drying for 2 hours, the zinc coordination polymer was obtained with a yield of 72%. The synthesized zinc coordination polymer was ground through a 100-mesh sieve and set aside for later use.
[0053] The X-ray single-crystal structure of the zinc coordination polymer prepared in this embodiment is shown in the figure. Figure 1 See the three-dimensional structure diagram. Figure 2 .from Figure 1 and Figure 2 As can be seen, each zinc atom coordinates with two carboxyl groups of pyromellitic acid and two pyridine nitrogen atoms of 2,4,6-tris(4-pyridyl)-1,3,5-triazine to form a tetrahedral configuration; then the carboxyl groups of pyromellitic acid and the pyridine nitrogen atoms of 2,4,6-tris(4-pyridyl)-1,3,5-triazine are all coordinated with zinc atoms to form a three-dimensional coordination polymer.
[0054] Thermogravimetric analysis (TGA) was used to characterize the thermal stability of the zinc coordination polymer product prepared in this embodiment. Specifically, the temperature was increased at a rate of 10 °C / min under nitrogen purging, and the thermogravimetric curve of the zinc coordination polymer was measured. The results are shown in [Figure number missing]. Figure 3 It can be seen that approximately 15% weight loss occurs within the temperature range of room temperature to 140℃, indicating that the zinc coordination polymer product contains a relatively large number of solvent molecules. After the solvent molecules evaporate, the zinc coordination polymer product shows almost no weight loss between 140 and 350℃, indicating that the zinc coordination polymer product can exist stably within this temperature range and has good thermal stability. In the temperature range of 350–800℃, the zinc coordination polymer product experiences rapid weight loss, indicating that the zinc coordination polymer product begins to decompose.
[0055] XRD analysis was performed on the zinc coordination polymer prepared in this embodiment, and the results are shown in the figure. Figure 4 It can be seen that the characteristic peaks of the powder diffraction XRD pattern are consistent with the positions of the characteristic peaks in the theoretical simulation, indicating that the structure of the synthesized zinc coordination polymer is consistent with the simulated structure and is a pure phase.
[0056] The chemical stability of the zinc coordination polymer prepared in this embodiment was analyzed, and the results are shown in the figure. Figure 5It can be seen that after immersing the zinc coordination polymer prepared in this embodiment in acidic and alkaline aqueous solutions with pH values of 2 and 12, respectively, for 24 hours, its XRD spectra are consistent with the theoretically simulated spectra. Figure 1 The results indicate that the structure of the coordination polymer did not change in acidic and alkaline aqueous solutions with pH values of 2 and 12, respectively, demonstrating good chemical stability.
[0057] The X-ray single-crystal diffraction data of the coordination polymer prepared in this embodiment are shown in Table 1.
[0058] Table 1. X-ray single-crystal diffraction data of zinc coordination polymers
[0059]
[0060]
[0061] Example 1 (using the zinc coordination polymer prepared in Example 1 as an example)
[0062] Catalytic synthesis of aryl formaldehyde / aryl ketone derivatives by aryl substitution of ethylene 2a~2f:
[0063] (1) Synthesis of compound 2a
[0064] 0.001 mol styrene 1a Dissolved in 2 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.003 mol hydrogen peroxide were added to the above solution. The mixture was then heated to 60 °C and reacted for 8 hours until the reactant 1a was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2a. The yield was 91%. NMR spectral data for compound 2a: 1 H NMR (400MHz, CDCl3): δ = 10.0 (s, 1H, ArCHO), 7.90 (d, J = 8.0Hz, 2H, ArH), 7.63-7.67 (m, 1H, ArH), 7.53-7.57 (m, 2H, ArH); 13 CNMR (100MHz, CDCl3): δ = 192.5, 136.4, 134.5, 129.8, 129.0.
[0065] (2) Synthesis of compound 2b
[0066] 0.001 mol 4-methoxystyrene 1b Dissolved in 2 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.003 mol hydrogen peroxide were added to the above solution. The mixture was then heated to 60 °C and reacted for 8 hours until the reactant 1b was completely reacted. Subsequently, the mixture was extracted twice with 10 mL of ethyl acetate each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with a mixture of petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2b. The yield was 93%. NMR spectral data for compound 2b: 1 H NMR (400MHz, CDCl3): δ = 9.89 (s, 1H, ArCHO), 7.85 (d, J = 8.8Hz, 2H, ArH), 7.01 (d, J = 8.8Hz, 2H, ArH), 3.89 (s, 3H, ArCH3); 13 C NMR (100MHz, CDCl3): δ = 190.9, 164.6, 132.0, 129.9, 114.3, 55.6.
[0067] (3) Synthesis of compound 2c
[0068] 0.001 mol 4-fluorostyrene 1c Dissolved in 2 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.003 mol hydrogen peroxide were added to the above solution. The mixture was then heated to 60 °C and reacted for 8 hours until the reactant 1c was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with a mixture of petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2c. The yield was 96%. Compound 2c NMR spectral data: 1 H NMR (400MHz, CDCl3): δ = 9.98 (s, 1H, ArCHO), 7.90-7.94 (m, 2H, ArH), 7.22 (t, J = 8.4Hz, 2H, ArH); 13 C NMR (100MHz, CDCl3): δ=190.6, 167.8, 165.3, 132.9 (J=2.7Hz), 132.3 (J=9.8Hz), 116.5 (J=22.1Hz).
[0069] (4) Synthesis of compound 2d
[0070] 0.001 mol 4-bromostyrene 1 day Dissolved in 2 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.003 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 8 hours until the reactant 1d was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2d. The yield was 92%. 2d NMR spectral data of the compound: 1 H NMR (400MHz, CDCl3): δ = 9.98 (s, 1H, ArCHO), 7.75-7.77 (m, 2H, ArH), 7.69-7.71 (m, 2H, ArH); 13 C NMR (100MHz, CDCl3): δ = 191.2, 135.1, 132.5, 131.0, 129.8.
[0071] (5) Synthesis of compound 2e
[0072] 0.001 mol of 1,1-diphenylethylene 1e Dissolved in 2 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.003 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 12 hours until the reactant 1e was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2e. The yield was 97%. Compound 2e NMR spectral data: 1 H NMR (400MHz, CDCl3): δ = 7.81 (d, J = 7.6Hz, 4H, ArH), 7.58-7.61 (m, 2H, ArH), 7.47-7.50 (m, 4H, ArH); 13 C NMR (100MHz, CDCl3): δ = 196.9, 137.6, 132.5, 130.1, 128.3.
[0073] The general structural formula of aryl-substituted ethylene is: R from 1a to 1e 1 and R 2 See Table 2.
[0074] Table 2
[0075]
[0076]
[0077] Example 2
[0078] A method for preparing a zinc coordination polymer:
[0079] Weigh 0.2 mmol of mesitylene benzoic acid, 0.2 mmol of 2,4,6-tris(4-pyridyl)-1,3,5-triazine, and 0.4 mmol of zinc nitrate hexahydrate, and add them to a mixed solution containing 1 mL of methanol and 3.5 mL of N,N-dimethylacetamide. Stir for 5 minutes at room temperature in air. Then, transfer the stirred solution to a 15 mL Teflon autoclave and heat to 110 °C in an oven for 72 hours. After the reaction is complete, cool to room temperature at a rate of 15 °C / h to obtain pale yellow crystals. After filtration, washing with methanol, and vacuum drying for 2 hours, the zinc coordination polymer is obtained with a yield of 68%. Grind the obtained coordination polymer through a 100-mesh sieve for later use.
[0080] Thermogravimetric analysis (TGA) was used to characterize the thermal stability of the zinc coordination polymer prepared in this embodiment. Specifically, the temperature was increased at a rate of 10 °C / min under nitrogen purging, and the thermogravimetric curve of the zinc coordination polymer was measured. The results are shown in [Figure number missing]. Figure 6 It can be seen that the zinc coordination polymer product prepared in this embodiment exhibits good thermal stability below 350°C, similar to that in Example 1.
[0081] XRD analysis was performed on the zinc coordination polymer prepared in this embodiment, and the results are shown in the figure. Figure 7 It can be seen that the characteristic peaks of the powder diffraction XRD pattern are consistent with the positions of the characteristic peaks in the theoretical simulation, indicating that the structure of the synthesized zinc coordination polymer is consistent with the simulated structure and is a pure phase.
[0082] Example 2 (using the zinc coordination polymer prepared in Example 2 as an example)
[0083] Catalytic synthesis of aryl formaldehyde / aryl ketone derivatives by aryl substitution of ethylene 2a~2f:
[0084] (1) Synthesis of compound 2a
[0085] 0.002 mol styrene 1a Dissolved in 3 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.006 mol hydrogen peroxide were added to the above solution. The mixture was then heated to 60 °C and reacted for 6 hours until the reactant 1a was completely reacted. Subsequently, the mixture was extracted twice with 10 mL of ethyl acetate each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with a mixture of petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2a. The yield was 93%. Nuclear magnetic resonance (NMR) spectral data for compound 2a: 1 H NMR (400MHz, CDCl3): δ = 10.0 (s, 1H, ArCHO), 7.90 (d, J = 8.0Hz, 2H, ArH), 7.63-7.67 (m, 1H, ArH), 7.53-7.57 (m, 2H, ArH); 13 CNMR (100MHz, CDCl3): δ = 192.5, 136.4, 134.5, 129.8, 129.0.
[0086] (2) Synthesis of compound 2b
[0087] 0.002 mol 4-methoxystyrene 1b Dissolved in 3 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.006 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 10 hours until the reactant 1b was completely reacted. Subsequently, the mixture was extracted twice with 10 mL of ethyl acetate each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with a mixture of petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2b. The yield was 94%. NMR spectral data for compound 2b: 1 H NMR (400MHz, CDCl3): δ = 9.89 (s, 1H, ArCHO), 7.85 (d, J = 8.8Hz, 2H, ArH), 7.01 (d, J = 8.8Hz, 2H, ArH), 3.89 (s, 3H, ArCH3); 13 C NMR (100MHz, CDCl3): δ = 190.9, 164.6, 132.0, 129.9, 114.3, 55.6.
[0088] (3) Synthesis of compound 2c
[0089] 0.002 mol 4-fluorostyrene 1c Dissolved in 3 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.006 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 10 hours until the reactant 1c was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2c. The yield was 97%. Compound 2c NMR spectral data: 1H NMR (400MHz, CDCl3): δ = 9.98 (s, 1H, ArCHO), 7.90-7.94 (m, 2H, ArH), 7.22 (t, J = 8.4Hz, 2H, ArH); 13 C NMR (100MHz, CDCl3): δ=190.6, 167.8, 165.3, 132.9 (J=2.7Hz), 132.3 (J=9.8Hz), 116.5 (J=22.1Hz).
[0090] (4) Synthesis of compound 2d
[0091] 0.002 mol 4-bromostyrene 1d Dissolved in 3 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.006 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 10 hours until the reactant 1d was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2d. The yield was 93%. 2d NMR spectral data of the compound: 1 H NMR (400MHz, CDCl3): δ = 9.98 (s, 1H, ArCHO), 7.75-7.77 (m, 2H, ArH), 7.69-7.71 (m, 2H, ArH); 13 C NMR (100MHz, CDCl3): δ = 191.2, 135.1, 132.5, 131.0, 129.8.
[0092] (5) Synthesis of compound 2e
[0093] 0.002 mol of 1,1-diphenylethylene 1e Dissolved in 3 mL of ethanol, 0.1 mol% zinc coordination polymer and 0.006 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 10 hours until the reactant 1e was completely reacted. Subsequently, the mixture was extracted twice with ethyl acetate, 10 mL each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (first eluted with pure petroleum ether, then eluted with petroleum ether and ethyl acetate in a volume ratio of 20:1) to obtain compound 2e. The yield was 95%. Compound 2e NMR spectral data: 1H NMR (400MHz, CDCl3): δ = 7.81 (d, J = 7.6Hz, 4H, ArH), 7.58-7.61 (m, 2H, ArH), 7.47-7.50 (m, 4H, ArH); 13 C NMR (100MHz, CDCl3): δ = 196.9, 137.6, 132.5, 130.1, 128.3.
[0094] Example 3
[0095] The catalyst used in Example 2 for the catalytic synthesis of benzaldehyde 2a was subjected to three catalytic cycles under the same experimental conditions as described above (the catalyst was collected by centrifugation after each reaction for the next reaction). The yield of benzaldehyde 2a after each cycle was calculated. Simultaneously, the zinc coordination polymer after three catalytic cycles was characterized by X-ray powder diffraction. The results are shown in [Figure 1]. Figure 8 and Figure 9 .from Figure 8 and Figure 9 As can be seen, the zinc coordination polymer prepared in Example 2 did not change its catalytic activity after three cycles, and the structure of the material remained unchanged, indicating that the material has good chemical and catalytic stability.
[0096] Comparative Example 1
[0097] Aryl formaldehyde / aryl ketone derivatives were synthesized by directly catalyzing the aryl substitution of ethylene with 2,4,6-tris(4-pyridyl)-1,3,5-triazine. The structural formula of 2,4,6-tris(4-pyridyl)-1,3,5-triazine is as follows:
[0098]
[0099] The specific application method is as follows:
[0100] 0.001 mol styrene 1a Dissolved in 2 mL of ethanol, 0.1 mol% 2,4,6-tris(4-pyridyl)-1,3,5-triazine and 0.003 mol hydrogen peroxide were added to the above solution. The mixture was then transferred to 60 °C and reacted for 8 hours until the reactant 1a was completely reacted. Subsequently, the mixture was extracted twice with 10 mL of ethyl acetate each time, and the solvent was dried under vacuum. The crude product was separated by column chromatography (the specific procedure is the same as in Example 1) to obtain compound 2a. The yield was 38%. NMR spectral data for compound 2a: 1H NMR (400MHz, CDCl3): δ = 10.0 (s, 1H, ArCHO), 7.90 (d, J = 8.0Hz, 2H, ArH), 7.63-7.67 (m, 1H, ArH), 7.53-7.57 (m, 2H, ArH); 13 C NMR (100MHz, CDCl3): δ = 192.5, 136.4, 134.5, 129.8, 129.0.
[0101] This comparative example directly used 2,4,6-tris(4-pyridyl)-1,3,5-triazine as a catalyst. The yield of its catalytic reaction of aryl-substituted ethylene to synthesize aryl formaldehyde / aryl ketone derivatives was significantly lower than that of the zinc coordination polymers prepared in Examples 1 and 2. This indicates that coordination of 2,4,6-tris(4-pyridyl)-1,3,5-triazine with zinc ions can significantly improve its catalytic activity.
[0102] Comparative Example 2
[0103] The same as step (1) in Example 1, except that the coordination polymer prepared in Example 2 is replaced with trimellitic acid, that is, trimellitic acid is directly used as a catalyst to catalyze styrene 1a. Transformation.
[0104] According to the results of proton nuclear magnetic resonance spectroscopy and column chromatography, benzaldehyde 2a was not detected. This indicates that pyromellitic acid cannot catalyze the conversion of styrene to benzaldehyde.
[0105] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. The application of a zinc coordination polymer in the catalytic conversion of aryl-substituted ethylene to aryl formaldehyde / aryl ketone derivatives, characterized in that, The preparation method of the zinc coordination polymer includes the following steps: Tristyric acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine and zinc nitrate hexahydrate were dissolved in a mixed solution of methanol and N,N-dimethylacetamide and stirred until homogeneous to obtain a solution. The solution was heated at 90-110°C and cooled to room temperature to obtain pale yellow crystals, which are the zinc coordination polymer.
2. The application of the zinc coordination polymer according to claim 1 in the catalytic conversion of aryl-substituted ethylene to aryl formaldehyde / aryl ketone derivatives, characterized in that, The molar ratio of the pyromellitic acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine and zinc nitrate hexahydrate is 1:1:
2.
3. The application of the zinc coordination polymer according to claim 1 in the catalytic conversion of aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives, characterized in that, The volume ratio of methanol to N,N-dimethylacetamide is 1:(3-3.5).
4. The application of the zinc coordination polymer according to claim 1 in the catalytic conversion of aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives, characterized in that, The heating time is 48 to 72 hours, and the cooling rate is 10 to 15 °C / min.
5. The application of the zinc coordination polymer according to claim 1 in the catalytic conversion of aryl-substituted ethylene to aryl formaldehyde / aryl ketone derivatives, characterized in that, The aryl-substituted ethylene includes styrene and its derivatives.
6. A method for catalytically converting aryl-substituted ethylene into aryl formaldehyde / aryl ketone derivatives, characterized in that, Aryl-substituted ethylene was dissolved in ethanol, and then a zinc coordination polymer and hydrogen peroxide were added. The resulting mixture was heated to 60°C. After the raw materials reacted completely, ethyl acetate was added for extraction, and the solvent was dried to obtain a crude product. The crude product was separated by column chromatography to obtain the aryl formaldehyde / aryl ketone derivative, wherein the zinc coordination polymer is the zinc coordination polymer of claim 1.
7. The method for catalytically converting aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives according to claim 6, characterized in that, The reaction time is 6 to 12 hours.
8. The method for catalytically converting aryl-substituted ethylene to arylformaldehyde / aryl ketone derivatives according to claim 6, characterized in that, The molar ratio of the aryl-substituted ethylene to the hydrogen peroxide is 1:3.