WO2022105250A1

WO2022105250A1 - Preparation of catechol-derived porous polymer and photocatalytic use of catechol-derived porous polymer-supported high-spin monatomic iron

Info

Publication number: WO2022105250A1
Application number: PCT/CN2021/104480
Authority: WO
Inventors: 刘宇宙; 谷得发
Original assignee: 北京航空航天大学
Priority date: 2020-11-20
Filing date: 2021-07-05
Publication date: 2022-05-27
Also published as: CN112321804B; CN112321804A

Abstract

A porous polymer, and a catechol-derived porous polymer and a catechol-derived porous polymer-supported high-spin monatomic iron catalyst prepared on the basis of the porous polymer. Further disclosed are a method for preparing the catalyst, and the use of the catalyst in catalyzing styrene epoxidation under illumination to prepare styrene oxide. The catalyst has a high catalytic activity, a high selectivity and a high stability, and a simple preparation method, and can be reused.

Description

Preparation of catechol-derived porous polymers and their photocatalytic applications with high-spin single-atom iron supported

technical field

The invention relates to a preparation method of a catechol-derived porous polymer, and the preparation and catalytic application of the porous polymer as a skeleton-supported high-spin single-atom iron catalyst.

Background technique

Styrene oxide is an important fine chemical that is widely used in organic synthesis, pharmaceutical and perfume industries. Therefore, it has broad application prospects.

At present, the synthetic methods of styrene oxide mainly include the following: 1. Halohydrin method (Liao Weilin, Chen Feibiao, a method for preparing epoxide by halohydrin method, Chinese patent, CN106518811A): the method technique is simple, but in Chlorine gas will be used in the production process, and many by-products will be produced at the same time, and the material consumption is high, and it is not in line with the road of green and sustainable development; 2. Peroxide oxidation method (Tan Rong, Deng Jiang, Yin Donghong, Schiff base Mn Complex, preparation and application in catalytic epoxidation of olefins, Chinese patent, CN108484673A; Yue Shuang, Zang Shuliang, Li Jun, Zhang Tingting, Ye Qiaolin, Hao Xiujia, Zhang Weidong, A method for olefin epoxidation, Chinese patent, CN104387343A; Bao Keyan, Mao Wutao, Xie Haiquan, Liu Guangyin, Luo Baomin, Li Beibei, a tungsten oxide nanosheet and its preparation method and catalytic application, Chinese patent, CN105498748A): This method introduces an oxygen source through peroxide, but it is often in the production process 3. Molecular oxygen oxidation method (Tang Q, Zhang Q, Wu H, et al. Epoxidation of styrene with molecular oxygen catalyzed by cobalt (II) -containing molecular sieves. J. Catal. 2005, 230, 384-397.): This method uses oxygen as an oxygen source, which requires expensive catalysts in the production process and poses a safety hazard. To sum up, these traditional synthetic methods have their own limitations. Therefore, it is very meaningful to invent a cheap and easily available catalyst with high catalytic activity.

Iron is widely distributed in life, accounting for 4.75% of the crustal content, second only to oxygen, silicon, and aluminum, ranking fourth in the crustal content. At the same time, it has attracted widespread attention because of its special extranuclear electron arrangement and low price. At present, there are few studies on iron-catalyzed olefin epoxidation. For example, Ji Hongbing et al. used μ-oxygen-binuclear tetra-(o-nitrophenyl) iron porphyrin as a catalyst, and oxygen was used as an oxidant to realize the epoxidation of styrene, but this method required the addition of isobutyraldehyde as a sacrificial agent, And it needs to be heated and the yield is only 85% (Ji Hongbing, Zhou Xiantai, Xu Jianchang, Pei Lixia, Wang Lefu, biomimetic catalytic oxygen oxidation of alkene or cycloalkene to prepare epoxy compound, Chinese patent CN1915983A); Mukherjee et al. The porphyrin iron is used as a catalyst to realize the epoxidation of styrene, but it needs to use sodium periodate as an oxygen source, which will introduce new impurities into the system (Mukherjee, Monalisa and Srivastava, Ashwani K, Process for preparation of Iron (III) porphyrin catalyst immobilized on Dowex resin and its application thereof in biomimetic oxidation, Indian patent IN2009DE00813A); Fariba Jalilian et al. used heteropolyacid iron salt as catalyst and hydrogen peroxide as oxygen source to realize styrene epoxidation, but only 8% yield (Fariba Jalilian, Bahram Yadollahi, Mostafa Riahi Farsani, Shahram Tangestaninejad, Hadi Amiri Rudbaria and Rouhollah Habibic, Catalytic performance of Keplerate polyoxomolybdates in green epoxidation of alkenes with hydrogen peroxide, 7, RSC 4., 2015, 5) ; Yingmu Zhang et al. supported iron on the MOF framework as a catalyst, but it was necessary to introduce tert-butyl hydroperoxide as an oxygen source to realize the epoxidation of styrene, which would introduce new impurities and be unsafe (Yingmu Zhang, Jialuo Li , Xinyu Yang, Peng Zhang, Jiandong Pang, Bao Liand Hong-Cai Zhou, A mesoporous NNN-pincer-based metal–organic framework scaffold for the preparation of noble-metal-free catalysts, Chem.Comm un., 2019, 55, 2023). Zhuohong Zhou et al. supported iron catalysts on inorganic ligands, but hydrogen peroxide was needed as an oxygen source to achieve styrene oxidation, and new impurities were introduced during the reaction (Zhuohong Zhou, Guoyong Dai, Shi Ru, Han Yu and Yongge Wei , Highly selective and efficient olefin epoxidation with pure inorganic-ligand supported iron Catalysts, Dalton Trans., 2019, 48, 14201). However, these catalysts have a single structure and are mainly porphyrin iron, and most of these catalytic systems require the introduction of sacrificial agents or oxidants, which will cause system pollution, and some require heating to react.

At present, in the research on the reaction of preparing ethylene oxide by styrene (Ding Liqin, Zhang Juntao, Liang Shengrong, Wang Xiaoquan, Research progress on catalysts for the preparation of styrene oxide by epoxidation of styrene, Journal of Xi'an Petroleum University, 2011, 26, 71 -77; Bai Xiangxiang, Guan Xiuhua, Shen Jian, Research Progress in Styrene Epoxidation, Chemical Technology, 2010, 18, 78-84; , Applied Chemical Industry, 43, 1489-1492), the conversion rate of most styrene is lower than 90% or the selectivity of ethylene oxide is lower than 90% (such as the Chinese Patent Publication No. CN103012323A discloses styrene epoxidation Reaction to prepare ethylene oxide, the catalyst is molybdenum Schiff base complex 2-acetylpyridine condensed o-aminophenol molybdenum complex, the conversion rate of styrene is 69.35%, and the selectivity of ethylene oxide is 80.19% ; Publication No. CN103204830A discloses a method for catalyzing styrene oxidation with a soluble zinc salt-modified heteroatom molecular sieve catalyst, and the conversion rate of styrene and the selectivity of ethylene oxide are difficult to reach more than 80% at the same time; Publication No. The patent of CN101972665A uses Co2+ as the active component, and adopts amino-functionalized mesoporous molecular sieve SBA-15 ion adsorption method to adsorb Co2+ to prepare styrene epoxidation catalyst, and the selectivity of ethylene oxide is up to 63.4%), However, when both of them are higher than 90%, oxidants are often introduced or the reaction conditions are harsh, and the cost of industrial application is relatively high.

Therefore, it is very important to develop a new type of iron catalyst that can achieve high conversion of styrene and high selectivity to produce ethylene oxide at room temperature.

SUMMARY OF THE INVENTION

In order to solve the above problems, the present invention provides a method for preparing a novel high-spin single-atom iron catalyst, and also provides a method for preparing ethylene oxide, which can directly oxidize styrene by using air as an oxygen source under illumination. , to achieve high conversion and high selectivity to generate ethylene oxide, and the catalyst can be reused. The technical scheme adopted by the present invention is as follows:

A porous polymer is characterized in that having the structure of compound I, IV (IV'), VII in formula 1:

Or have the following structure:

Or have the following structure:

That is, from the above reaction, the porous polymer with the structure of I or IV(IV') or VII, the porous polymer derived from catechol with the structure of compound II or V(V') or VIII can be obtained in turn, and the compound Structures III or VI(VI') or IX Catechol-derived porous polymer-supported high-spin single-atom iron catalysts. Wherein, in the compound, R1, R4, R5, R6, R9 are selected from CH and its derived various alkyl chains, N, O, S; R2, R3 are selected from C1-C6 alkoxy groups, which can be the same respectively or different; n1, n2, n3 are integers respectively, and n1+n2+n3>=1 (that is, at least one is not 0); R7 is selected from CH and its derived various alkyl chains, benzene rings, 1,3 ,5-triazine; R8 is selected from C, C=C, porphyrin; R10, R11 can be two H or 1 FeCl, thereby obtaining the following structural fragments with adjacent groups:

In one of the porous polymer-supported high-spin single-atom iron catalyst structures (III or VI(VI') or IX),

The number is at least 1 (which is specifically positively related to the amount of iron).

The method for preparing a porous polymer having compound I, IV (IV') and VII structures is characterized in that hexaalkoxy-substituted tribenzylbenzene and dialdehyde (trialdehyde, tetraaldehyde) or derivatives thereof A catalyst is added to the mixed system of the compound to finally obtain a porous polymer;

The method for preparing a porous polymer is characterized in that it specifically comprises the following steps:

(1) in the mixed system of hexaalkoxy-substituted tribenzylbenzene, dialdehyde (trialdehyde, tetraaldehyde) or its derivative, acetic anhydride and catalyst, add solvent and heat up reaction;

(2) in step (1) gained mixed solution, add catalyst reaction;

(3) post-processing is carried out to the mixed solution obtained in step (2) to obtain compounds I, IV (IV') and VII;

The preparation method of the porous polymer is characterized in that the catalyst in the step (1) is FeCl ₃ , the solvent in the step (1) is dichloromethane, and the hexaalkoxy-substituted trichloromethane in the step (1) is The molar ratio of benzylbenzene, dialdehyde (trialdehyde, tetraaldehyde) or its derivatives, acetic anhydride and catalyst is n (hexaalkoxy-substituted tribenzylbenzene): n (dialdehyde (trialdehyde, tetraaldehyde) ) or its derivatives): n (acetic anhydride): n (catalyst) = 1:1:25:0.1 to n (hexaalkoxy-substituted tribenzylbenzene):n (dialdehyde (trialdehyde, tetraaldehyde) ) or its derivatives): n (acetic anhydride): n (catalyst) = 1:3:100:1, where n is the amount of substance;

The preparation method of any one of the porous polymers, wherein the catalyst in step (2) is FeCl ₃ , and the molar ratio of the amount of the catalyst to the amount of tribenzyl benzene substituted with hexaalkoxy is n(hexaalkoxy yl-substituted tribenzylbenzene):n(FeCl3)= ₁ :100 to n(hexaalkoxy-substituted tribenzylbenzene):n(FeCl3)= ₁ :200000, wherein n is the amount of substance;

The preparation method of the porous polymer is characterized in that the post-treatment in step (3) is: adding methanol to quench, then filtering, and washing the solid residue with methanol and water;

A catechol-derived porous polymer is characterized in that it has the structures of the above-mentioned compounds II, V(V') and VIII in formula 1; in the compound, R1, R4, R5, R6, R9 are selected from CH and its Various derived alkyl chains, N, O, S; n1, n2, n3 are integers, respectively, and n1+n2+n3>=1 (that is, at least one is not 0); R7 is selected from CH and its derivatives. Alkyl chain, benzene ring, 1,3,5-triazine; R8 is selected from C, C=C, porphyrin.

The method for preparing a catechol-derived porous polymer represented by compounds II, V(V') and VIII is characterized in that a reagent is added to the compound to carry out a hydrolysis reaction to finally obtain a catechol-derived porous polymer. polymer;

The method for preparing a catechol-derived porous polymer is characterized in that it specifically comprises the following steps:

(1) adding solvent in the mixed system of compound I, IV (IV'), VII and catalyst, then stirring reaction;

(2) post-processing the obtained mixed solution in step (1) to obtain compound II, V(V') and VIII;

The preparation method of the catechol-derived porous polymer is characterized in that, the catalyst described in step (1) is boron tribromide, and the ratio of the amount of the catalyst to the amount of compound I/IV(IV')/VII is 1 mg (Compound I, IV (IV'), VII): 1 mL (boron tribromide) to 500 mg (compound I, IV (IV'), VII): 1 mL (boron tribromide), most preferably 100 mg (compound I, IV(IV'), VII): 1 mL (boron tribromide).

The preparation method of the catechol-derived porous polymer is characterized in that the post-treatment described in the step (2) is: adding water to quench, then filtering, and washing the solid residue with an organic solvent and water;

A catechol-derived porous polymer-supported single-atom iron catalyst with high spin , R9 is selected from CH and various alkyl chains derived from it, N, O, S; n1, n2, n3 are integers respectively, and n1+n2+n3>=1 (that is, at least one is not 0); R7 is selected Various alkyl chains, benzene rings, 1,3,5-triazine derived from CH and its derivatives; R8 is selected from C, C=C, porphyrin; R10, R11 can be two H or one FeCl, thus The following structural fragments are obtained with adjacent groups:

In one of the porous polymer-supported high-spin single-atom iron catalyst structures,

The number is at least 1.

The method for preparing a catechol-derived porous polymer-supported high-spin single-atom iron catalyst with compounds III, VI(VI'), and IX is characterized by adding compounds II, V(V'), VIII to compounds II, V(V'), and VIII. Add alkali to react and then add iron salt to catalyze the reaction to finally obtain a porous polymer-supported high-spin single-atom iron catalyst derived from catechol;

The method for preparing a catechol-derived porous polymer-supported high-spin single-atom iron catalyst is characterized in that it specifically comprises the following steps:

(1) disperse the catechol-derived porous polymer with the general formula of compound II, V(V') and VIII in formula 1 in a solvent, add an alkali, and after the reaction, filter and wash to obtain a solid powder;

(2) dispersing the solid powder obtained in step (1) in a solvent, then adding an iron source, after the reaction, after post-processing to obtain a catechol-derived porous polymer-supported high-spin single-atom iron catalyst;

The preparation method of the catalyst is characterized in that the solvent described in the step (1) is ethanol, the alkali described in the step (1) is NaOH, and the amounts of compounds II, V(V') and VIII in the step (1) are the same as The amount of the base is mixed in a mass ratio of m (compound II/V(V')/VIII): m (base) = 1: 0.0001 to m (compound II, V(V'), VIII): m (base) = 1 : 1, wherein m is quality; The reaction conditions described in step (1) are ultrasonic reaction or magnetic stirring reaction, use ethanol and deionized water to wash;

The preparation method of the catalyst is characterized in that, in step ( ₂ ), the iron source is FeX or its hydrate, X is -Cl or -Br, and the mass ratio of the amount of iron source to the amount of compound II is m (compound II). II): m(iron source) = 1:0.0001 to m(compound II/V(V')/VIII): m(iron source) = 1:1, where m is mass; the reaction described in step (2) The condition is an ultrasonic reaction or a magnetic stirring reaction, and the post-processing described in the step (2) is, filtering, and washing the solid residue with an organic solvent and water;

The application of the catalyst in the epoxidation of styrene is characterized in that the above-mentioned porous polymer derived from catechol is used to support a high-spin single-atom iron catalyst, and under illumination, air is used as an oxygen source to realize the ring of styrene. oxidation reaction;

The application includes: mixing styrene and a catalyst, adding a solvent, reacting with light, sampling the mixture, and measuring the product yield; the specific steps include:

(1) mixing styrene and the above-mentioned catechol-derived porous polymer-supported high-spin single-atom iron catalyst, and adding a solvent;

(2) Under the illumination of 10-35°C, the magnetic stirring reaction is performed for 3-12h;

(3) The mixture was sampled to determine the product yield.

The application is characterized in that the solvent in step (1) is preferably DMF; the molar ratio of mixing in step (1) is n (styrene): n (catalyst) = 1: 0.01 to n (benzene Ethylene): n(catalyst)=1:0.1, where n is the amount of substance; the yield is preferably determined by a high performance gas mass spectrometer; the oxygen source used for the catalytic reaction is air.

The catalyst can be reused for more than 3 times without loss of catalytic activity and selectivity. The present invention adopts the above-mentioned technical side to have the following beneficial effects:

1. The present invention creatively provides a method for preparing a catechol-derived porous polymer with a new structure

2. The present invention also provides a preparation method capable of successfully preparing the catechol-derived porous polymer-supported high-spin single-atom iron catalyst.

3. The present invention also provides an application method of a high-spin single-atom iron catalyst supported by a catechol-derived porous polymer of a described brand-new structure, and found that it can effectively catalyze the styrene epoxidation reaction, and its conversion The rate can reach 100% and the selectivity is 94%. It can be seen that the catechol-derived porous polymer-supported high-spin single-atom iron catalyst synthesized in this application has the advantages of high reactivity and good selectivity. Compared with the iron catalyst, higher styrene conversion rate and ethylene oxide selectivity are simultaneously achieved, which is difficult to achieve in the prior art.

4. Most of the catalysts used in the prior art cannot be recycled because they have no recovery value, are difficult to separate or are difficult to ensure the purity after separation, and the above-mentioned catalysts of the present application can overcome the above-mentioned defects of the catalysts, and can be used multiple times, at least 3 times. At the same time, the catalytic activity and selectivity are not lost.

Description of drawings

Fig. 1 Nitrogen adsorption-desorption isotherms and pore size distributions of catechol-derived porous polymers (POG-OMe).

Fig.2 Infrared absorption spectra of POG-OMe and POG-OH

Fig.3 UV absorption spectrum of POG-OH

Fig.4 C NMR spectra of POG-OMe and POG-OH

Fig.5 HAADF-STEM image of 5%Fe@POG-OH (5% is the mass ratio of Fe to the catalyst)

Figure 6. High-efficiency gas mass spectrometry of photocatalytic reaction

Figure 7 Photocatalytic cycle data graph

Detailed ways

The present invention will be further described below in conjunction with specific embodiments. It should be understood that these implementations are only used to illustrate the present invention,

It is not intended to limit the scope of the present invention.

Example 1

A kind of preparation of porous polymer, the steps are as follows:

In 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4mmol), 9,9-dimethyl-2,7-fluorene dialdehyde (0.6mmol), acetic anhydride (20mmol) 100 mL of dichloromethane solvent was added to the mixed system with ferric chloride (0.08 mmol), and the reaction was conducted under magnetic stirring at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 2 (POG-OMe) with a yield of 91%. BET characterization of POG-OMe (see Figure 1 of the accompanying drawings) showed that it exhibited rapid absorption at lower relative pressures (P/P ₀ <0.001), indicating the presence of a large number of micropores. NLDFT calculations revealed that POG-OMe mainly contained micropores with a size of 1.67 nm, which was consistent with the calculated value of 1.68 nm derived from the structural model of POG-OMe. In addition, we calculated the BET surface area of POG-OMe to be as high as 848m ² g ^-1 from the data obtained from the test. Afterwards, POG-OMe was characterized by infrared and nuclear magnetic properties (see Figure 2 of the accompanying drawings), and the infrared characteristic peak of COC at 1112 cm ^-1 could be seen through the infrared test; at the same time, CO-CH at 55 ppm could be seen from the solid carbon spectrum nuclear magnetic resonance ₃ signal peaks.

Example 2

A kind of preparation of catechol-derived porous polymer, the steps are as follows:

Weigh 100 mg of POG-OMe and then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath, magnetically The reaction was stirred for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 3 (POG-OH) in 95% yield. At the same time, POG-OH was characterized by infrared and NMR (see Figure 4), and the characteristic peak signal of -OH at 3500cm ^-1 could be seen through infrared test; at the same time, the signal peak of C-OH appeared at 150ppm. Then the POG-OH was tested by UV, and the results are shown in Figure 3 of the accompanying drawings.

Example 3

A kind of preparation that contains the porous polymer derived from nitrogen heterocyclic catechol, the steps are as follows:

in 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4 mmol), 9H-carbazole-2,7-dialdehyde (0.6 mmol), acetic anhydride (20 mmol) and trichloride 100 mL of dichloromethane solvent was added to the iron (0.08 mmol) mixed system, and the reaction was conducted under magnetic stirring at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. The system was then quenched by adding methanol, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product (shown in formula 4). By performing BET test on the product, it can be calculated from the obtained data that the BET surface area of the product represented by formula 4 is as high as 893 m ² g ^-1 .

Example 4

Weigh the product of formula 4 (100 mg) and then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -78 °C, add boron tribromide (1 mL), and transfer the reaction system to a 50 °C oil bath, Magnetic stirring reaction for 48h. The reaction was quenched by adding deionized water, and the solid residue was washed with water and methanol to obtain the product shown in formula 5

Example 5

In a mixed system of 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4mmol), isophthalaldehyde (0.6mmol), acetic anhydride (20mmol) and ferric chloride (0.08mmol) 100 mL of dichloromethane solvent was added to the solution, and the reaction was magnetically stirred at 25 °C for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 6.

Example 6

Weigh 100 mg of the product shown in formula 6, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20 ° C, add boron tribromide (1 mL), and transfer the reaction system to a 50 ° C oil bath , the magnetic stirring reaction was carried out for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 7.

Example 7

in 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4 mmol), 3,5-dialdehyde pyridine (0.6 mmol), acetic anhydride (20 mmol) and ferric chloride (0.08 mmol), 100 mL of dichloromethane solvent was added to the mixed system, and the reaction was conducted under magnetic stirring at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 8.

Example 8

Weigh 100 mg of the product shown in formula 8, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath , the magnetic stirring reaction was carried out for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 9.

Example 9

in 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4 mmol), 2,6-dialdehyde naphthalene (0.6 mmol), acetic anhydride (20 mmol) and ferric chloride (0.08 mmol), 100 mL of dichloromethane solvent was added to the mixed system, and the reaction was conducted under magnetic stirring at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 10.

Example 10

Weigh 100 mg of the product shown in formula 10, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath , the magnetic stirring reaction was carried out for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 11.

Example 11

in 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4 mmol), 2,6-dialdehyde anthracene (0.6 mmol), acetic anhydride (20 mmol) and ferric chloride (0.08 mmol), 100 mL of dichloromethane solvent was added to the mixed system, and the reaction was conducted under magnetic stirring at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 12.

Example 12

Weigh 100 mg of the product shown in formula 12, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath , the magnetic stirring reaction was carried out for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 13.

Example 13

in 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4 mmol), thieno[3,2-B]thiophene-2,5-dicarbaldehyde (0.6 mmol), acetic anhydride ( 20 mmol) and ferric chloride (0.08 mmol) were added to the mixed system of 100 mL of dichloromethane solvent, and the reaction was magnetically stirred at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 14.

Example 14

Weigh 100 mg of the product shown in formula 14, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath , the magnetic stirring reaction was carried out for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 15.

Example 15

In 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4mmol), 1,3,5-tris(p-formylphenyl)benzene (0.6mmol), acetic anhydride (20mmol) 100 mL of dichloromethane solvent was added to the mixed system with ferric chloride (0.08 mmol), and the reaction was conducted under magnetic stirring at 25° C. for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. Then methanol was added to the system to quench, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 16.

Example 16

Weigh 100 mg of the product shown in formula 16, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath , the reaction was magnetically stirred for 48 h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 17 (POG-3S-OH).

Example 17

in 1,3,5-tris(3,4-dimethoxybenzyl)benzene (0.4mmol), tetrakis(4-formylbenzene)methane (0.6mmol), acetic anhydride (20mmol) and ferric chloride ( 0.08 mmol) was added to the mixed system with 100 mL of dichloromethane solvent, and the reaction was conducted under magnetic stirring at 25 °C for 48 h. Ferric chloride (72 mmol) was added to the system again, and the reaction was magnetically stirred for 12 h at 25° C. under an argon atmosphere. The system was then quenched by adding methanol, filtered under reduced pressure, and the solid residue was washed with water and methanol to obtain the product shown in formula 18.

Example 18

Weigh 100 mg of the product represented by formula 18, then add 200 mL of CH ₂ Cl ₂ under argon, place the reaction system at -20°C, add boron tribromide (1 mL), and transfer the reaction system to a 50°C oil bath , the magnetic stirring reaction was carried out for 48h. Deionized water was added to quench the reaction, and the solid residue was washed with water and methanol to give the product of formula 19 (POG-4S-OH).

Example 19

A kind of preparation of catechol-derived porous polymer-supported high-spin single-atom iron catalyst, the steps are as follows:

Weigh POG-OH (100mg) and sodium hydroxide (40mg) and add 200mL of ethanol, i.e. m(POG-OH): m(sodium hydroxide)=1:0.4 meets the standard of claim 15, ultrasonicate for 1h at room temperature, filter And washed the solid 3 times with deionized water, transferred to a beaker and added FeCl ₂ ·4H ₂ O (18 mg), i.e. m(POG-OH): m(FeCl ₂ ·4H ₂ O)=1:0.18 according to claim 16 , 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed with water and ethanol for 3 times to obtain the catechol-derived porous polymer supported high-spin single-atom iron catalyst 5% Fe@POG-OH (5% as shown in formula 20). % is the mass ratio of iron to the catalyst), and the yield is 100%. 5%Fe@POG-OH means that the mass ratio of iron atoms in the catalyst to the mass of the whole catalyst is 5%. At the same time, the catalyst was characterized by HAADF-STEM (see Figure 5 in the accompanying drawings), and the results showed that iron ions were uniformly distributed on the entire framework. Metal content was determined by ICP.

Example 20

The preparation of 3% Fe@POG-OH (3% is the mass ratio of iron to the catalyst), the steps are as follows: Weigh POG-OH (100mg) and sodium hydroxide (24mg) and add 200mL of ethanol, namely m(POG-OH ): m (sodium hydroxide) = 1:0.24 meets the standard of claim 15, sonicated for 1 h at room temperature, filtered and washed the solid with deionized water 3 times, transferred to a beaker and added FeCl ₂ ·4H ₂ O (10.8 mg) , that is, m(POG-OH): m(FeCl ₂ ·4H ₂ O)=1:0.108, which meets the standard of claim 16, 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed with water and ethanol for 3 times to obtain phthalate Phenol-derived porous polymer supported high-spin single-atom iron catalyst (3% Fe@POG-OH) with 100% yield. Metal content was determined by ICP.

Example 21

The preparation of 1% Fe@POG-OH (1% is the mass ratio of iron to the catalyst), the steps are as follows: Weigh POG-OH (100mg) and sodium hydroxide (8mg) and add 200mL of ethanol, namely m(POG-OH ): m (sodium hydroxide) = 1:0.08 meets the standard of claim 15, sonicated for 1 h at room temperature, filtered and washed the solid with deionized water 3 times, transferred to a beaker and added FeCl ₂ ·4H ₂ O (3.6 mg) , that is, m(POG-OH): m(FeCl ₂ ·4H ₂ O)=1:0.036, which meets the standard of claim 16, 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed with water and ethanol 3 times to obtain phthalate Phenol-derived porous polymer supported high-spin single-atom iron catalyst (1% Fe@POG-OH) with 100% yield. Metal content was determined by ICP.

Example 22

The preparation of 0.5% Fe@POG-OH (0.5% is the mass ratio of iron to the catalyst), the steps are as follows: Weigh POG-OH (100 mg) and sodium hydroxide (4 mg) and add 200 mL of ethanol, namely m(POG-OH ): m (sodium hydroxide) = 1:0.04 meets the standard of claim 15, sonicated for 1 h at room temperature, filtered and washed the solid with deionized water 3 times, transferred to a beaker and added FeCl ₂ ·4H ₂ O (1.8 mg) , that is, m(POG-OH): m(FeCl ₂ ·4H ₂ O)=1:0.018, which meets the standard of claim 16, 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed with water and ethanol 3 times to obtain phthalate Phenol-derived porous polymer supported high-spin single-atom iron catalyst (0.5% Fe@POG-OH) with 100% yield. Metal content was determined by ICP.

Example 23

The preparation of 0.01% Fe@POG-OH (0.01% is the mass ratio of iron to the catalyst), the steps are as follows: Weigh POG-OH (100mg) and sodium hydroxide (0.08mg) and add 200mL of ethanol, namely m(POG- OH): m (sodium hydroxide) = 1:0.0008 meets the standard of claim 15, sonicated for 1 h at room temperature, filtered and washed the solid with deionized water 3 times, transferred to a beaker and added FeCl ₂ ·4H ₂ O (0.036 mg ), that is, m(POG-OH): m(FeCl ₂ ·4H ₂ O)=1:0.00036, which meets the standard of claim 16, 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed with water and ethanol 3 times to obtain o-benzene Diphenol-derived porous polymer supported high-spin single-atom iron catalyst (0.01% Fe@POG-OH) with 100% yield. Metal content was determined by ICP.

Example 24

Weigh POG-3S-OH (100mg) and sodium hydroxide (40mg) and add 200mL of ethanol, i.e. m(POG-3S-OH): m(sodium hydroxide)=1:0.4 meets the standard of claim 15, at room temperature Sonicated for 1 h, filtered and washed the solid 3 times with deionized water, transferred to a beaker and added FeCl ₂ ·4H ₂ O (18 mg), i.e. m(POG-3S-OH): m(FeCl ₂ ·4H ₂ O)=1 : 0.18 meets the standard of claim 16, 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed with water and ethanol 3 times to obtain a catechol-derived porous polymer supported high-spin single-atom iron catalyst 5% Fe as shown in formula 21 @POG-3S-OH (5% is the mass ratio of iron to the catalyst), the yield is 100%. Metal content was determined by ICP.

Example 25

Weigh POG-4S-OH (100mg) and sodium hydroxide (40mg) and add 200mL of ethanol, i.e. m(POG-4S-OH): m(sodium hydroxide)=1:0.4 meets the standard of claim 15, at room temperature Sonicated for 1 h, filtered and washed the solid 3 times with deionized water, transferred to a beaker and added FeCl ₂ ·4H ₂ O (18 mg), i.e. m(POG-4S-OH): m(FeCl ₂ ·4H ₂ O)=1 : 0.18 meets the standard of claim 16, 200 mL of ethanol, sonicated for 1 h at room temperature, filtered and washed 3 times with water and ethanol to obtain a catechol-derived porous polymer-supported high-spin single-atom iron catalyst 5% Fe as shown in formula 22 @POG-4S-OH (5% is the mass ratio of iron to the catalyst), the yield is 100%. Metal content was determined by ICP.

Example 26

A kind of preparation of catechol-derived porous polymer-supported single-atom palladium catalyst, the steps are as follows:

Weigh POG-OH (100 mg) and sodium hydroxide (40 mg), add 200 mL of ethanol, sonicate for 1 h at room temperature, filter and wash the solid with deionized water 3 times, transfer to a beaker and add PdCl ₂ (8.33 mg) 200 mL of ethanol, room temperature Ultrasonic for 1 h, filtered and washed with water and ethanol for 3 times to obtain a catechol-derived porous polymer-supported single-atom palladium catalyst 5% Pd@POG-OH (5% is the mass ratio of palladium to the catalyst), and the yield is is 100%. Metal content was determined by ICP.

For the epoxidation of styrene, different contents of Fe@POG-OH, 5%Pd@POG-3S-OH, 5%Pd@POG-4S-OH, ferric chloride, ferric chloride and trichloride were taken respectively. Iron/catechol system makes catalyzer, also tested the reaction situation under conditions such as no catalyzer simultaneously, comparative data is shown in Table 1:

Application Example 1

Weigh styrene (0.1 mmol) and catechol-derived porous polymer-supported high-spin single-atom iron catalyst (1 mol%, 5% Fe@POG-OH) into a 10 mL quartz tube, add 1 mL N,N- Using air as oxygen source, dimethylformamide was magnetically stirred under white light at room temperature for 10 hours. The styrene conversion rate was 100% and the yield of ethylene oxide was 94% by high performance gas mass spectrometry. The catalyst was recovered by centrifugation, used again, and circulated 3 times, and the catalyst still maintained its original catalytic activity and selectivity (the cycle result is shown in Figure 7 of the accompanying drawings). All the yields and selectivities were determined by high performance gas mass spectrometry, using dodecane as the internal standard, and the gas quality results of the first catalytic results are shown in Figure 6 of the accompanying drawings. Before the reaction of the system, styrene peaked at t=2.2min , the raw material peak disappeared after the reaction, and the characteristic peak of epoxy styrene appeared at t=3.1min, and the non-target product peak (minimal amount) appeared at t=3.0min.

Application Example 2

Weigh styrene (0.1 mmol) and catechol-derived porous polymer-supported high-spin single-atom iron catalyst (1 mol%, 3% Fe@POG-OH) into a 10 mL quartz tube, add 1 mL of N,N-di Methylformamide was magnetically stirred under white light at room temperature for 10 h with air as the oxygen source. The styrene conversion rate was 85% and the yield of ethylene oxide was 90% by high performance gas mass spectrometry.

Application Example 3

Weigh styrene (0.1 mmol) and catechol-derived porous polymer-supported high-spin single-atom iron catalyst (1 mol%, 1% Fe@POG-OH) into a 10 mL quartz tube, add 1 mL of N,N-di Methylformamide, using air as the oxygen source, was magnetically stirred under white light at room temperature for 10 hours, and the styrene conversion rate was 96% and the yield of ethylene oxide was 89% by high-performance gas mass spectrometry.

Application Example 4

Weigh styrene (0.1 mmol) and catechol-derived porous polymer-supported high-spin single-atom iron catalyst (1 mol%, 5% Fe@POG-3S-OH) into a 10 mL quartz tube, add 1 mL N,N - Dimethylformamide, using air as the oxygen source, magnetic stirring for 10 hours under white light at room temperature, the styrene conversion rate is 100% and the yield of ethylene oxide is 93% by high performance gas mass spectrometry detection.

Application Example 5

Weigh styrene (0.1 mmol) and catechol-derived porous polymer-supported high-spin single-atom iron catalyst (1 mol%, 5% Fe@POG-4S-OH) into a 10 mL quartz tube, add 1 mL N,N - Dimethylformamide, using air as the oxygen source, magnetic stirring for 10 hours under white light at room temperature, the styrene conversion rate is 98% and the yield of ethylene oxide is 93% by high performance gas mass spectrometry detection.

Application Example 1

Weigh styrene (0.1 mmol) and catechol-derived porous polymer-supported single-atom palladium catalyst (1 mol%, 5% Pd@POG-OH) into a 10 mL quartz tube, add 1 mL of N,N-dimethylformaldehyde Using air as the oxygen source, magnetic stirring was performed for 10 h under white light at room temperature. The styrene conversion rate was 0% and the yield of ethylene oxide was 0% by high-performance gas mass spectrometry.

Application Comparative Example 2 (Example 5 of CN101972665A)

Using Co2+ as the active component, the styrene epoxidation catalyst was prepared by adsorbing Co2+ on an amino-functionalized mesoporous molecular sieve SBA-15 ion adsorption method. For the reaction under oxygen conditions, taking Example 5 as an example, the highest selectivity of ethylene oxide is 63.4%, corresponding to a styrene conversion rate of 81.7%.

Application Comparative Example 3 (Example 3 of CN103012323A)

Firstly, 2-acetylpyridine condensed o-aminophenol molybdenum complex was synthesized and used as catalyst. Take 2.5mmol (0.29ml) of styrene, 5mmol (0.72ml) of tert-butyl hydroperoxide (TBHP), 6ml of benzene as solvent, 0.025mmol of catalyst, add to 25ml single-necked flask, place in 80°C oil bath and stir, condensate and reflux 9h. The molar ratio of styrene to catalyst was 100:1. The final conversion rate of styrene was 69.35%, and the selectivity of ethylene oxide was 80.19%.

Application Comparative Example 4

Weigh styrene (0.1 mmol) into a 10 mL quartz tube, add 1 mL of N,N-dimethylformamide, use air as the oxygen source, and magnetically stir for 10 h under white light at room temperature. The styrene is detected by high-efficiency gas mass spectrometry. The conversion was 0% and the yield of ethylene oxide was 0%.

Application Comparative Example 5

Weigh styrene (0.1 mmol) and ferric chloride (1 mol%) into a 10 mL quartz tube, add 1 mL of N,N-dimethylformamide, use air as the oxygen source, and stir magnetically for 10 h under white light at room temperature , the styrene conversion rate was 22% and the yield of ethylene oxide was 64% by high-efficiency gas mass spectrometry.

Application Comparative Example 6

Weigh styrene (0.1 mmol) and ferric chloride (1 mol%) into a 10 mL quartz tube, add 1 mL of N,N-dimethylformamide, use air as the oxygen source, and stir magnetically for 10 h under white light at room temperature , the styrene conversion rate was 20% and the yield of styrene oxide was 59% by high-efficiency gas mass spectrometry.

Application Example 7

Weigh styrene (0.1mmol) and ferric chloride/catechol (1mol%, ferric chloride:catechol=1:1) into a 10mL quartz tube, add 1mL N,N-diphenol Methylformamide, using air as the oxygen source, was magnetically stirred for 6 hours under white light at room temperature, and the styrene conversion rate was 29% and the yield of ethylene oxide was 68% by high-performance gas mass spectrometry.

Table 1:

It can be seen that, according to the selected initial reaction raw materials such as tribenzylbenzene and polyaldehydes, the content of iron with the porous polymer-supported high-spin single-atom iron catalyst derived from catechol is finally obtained as shown in Application Examples 1-3, Compared with the comparative example, it can be seen that the catechol-derived porous polymer-supported high-spin single-atom iron catalyst synthesized in the present application has the advantages of high reactivity and good selectivity. Compared with other kinds of metals and other iron catalysts, At the same time, higher conversion rate of styrene and selectivity of ethylene oxide are realized, which can fully meet the needs of existing production.

In addition, it should be mentioned that most of the catalysts used in the prior art cannot be recycled because they have no recovery value, are difficult to separate, or are difficult to ensure the purity after separation. It is used for at least 3 times and the catalytic activity and selectivity are not lost.

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 the protection scope of the present invention. Although the present invention is described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that, The technical solutions of the present invention may be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention.

Claims

A porous polymer, characterized in that it has the structure of the following compound I or IV (IV') or VII:

In the compound, R1, R6 are selected from CH and various alkyl chains derived from it, N, O, S; R2, R3 are selected from C1-C6 alkoxy groups, which can be the same or different respectively; R4, R5, R9 Selected from CH and various alkyl chains derived from it, N, O, S; n1, n2, n3 are integers respectively, and n1+n2+n3>=1; R7 is selected from CH and various alkyl derived from it chain, benzene ring, 1,3,5-triazine; R8 is selected from C, C=C, porphyrin.
A method for preparing a porous polymer with compound I or IV (IV') or VII structure as claimed in claim 1, characterized in that hexaalkoxy-substituted tribenzylbenzene and dialdehyde (trialdehyde, tetraaldehyde) ) or its derivatives in the mixed system by adding a catalyst to react to finally obtain a porous polymer.
A kind of preparation method of the porous polymer with compound I or IV (IV') or VII structure as claimed in claim 2, is characterized in that specifically comprises the steps:

(1) in the mixed system of hexaalkoxy-substituted tribenzylbenzene, dialdehyde (trialdehyde, tetraaldehyde) or its derivative, acetic anhydride and catalyst, add solvent and heat up reaction;

(2) in step (1) gained mixed solution, add catalyst reaction;

(3) Post-processing the mixed solution obtained in step (2) to obtain compounds I, IV (IV') and VII.
The method for preparing a porous polymer according to claim 2 and 3, wherein the catalyst in step (1) is FeCl 3 , the solvent in step (1) is dichloromethane, and in step (1) six Alkoxy-substituted tribenzylbenzene, dialdehyde (trialdehyde, tetraaldehyde) or its derivatives, acetic anhydride and catalyst mixed molar ratio is n (hexaalkoxy-substituted tribenzylbenzene): n (dialdehyde (trialdehyde, tetraaldehyde) or derivatives thereof): n (acetic anhydride): n (catalyst) = 1:1:25:0.1 to 1:3:100:1, where n is the amount of substance.
The method for preparing a porous polymer according to any one of claims 2 and 3, wherein the catalyst in step (2) is FeCl 3 , and the molar ratio of the hexaalkoxy-substituted tribenzylbenzene to the amount of the catalyst is: n(hexaalkoxy-substituted tribenzylbenzene):n(FeCl3)= 1 :100 to 1:200000, where n is the amount of substance.
The method for preparing a porous polymer according to any one of claims 2 and 3, wherein the post-treatment in step (3) is: adding methanol to quench, then filtering, and washing the solid residue; wherein methanol is preferably used and water wash.
A catechol-derived porous polymer characterized by having the structure of compound II or V(V') or VIII:

In the compound, R1, R6 are selected from CH and various alkyl chains derived from it, N, O, S; R4, R5, R9 are selected from CH and various alkyl chains derived from CH and its derivatives, N, O, S; n1 , n2 and n3 are integers respectively, and n1+n2+n3>=1; R7 is selected from CH and its derived various alkyl chains, benzene rings, 1,3,5-triazine; R8 is selected from C, C =C, porphyrin.
A method for preparing a catechol-derived porous polymer with compound II or V(V') or VIII as claimed in claim 7, wherein the compound I or IV(IV' as claimed in claim 1 is used ) or VII for hydrolysis to finally obtain a catechol-derived porous polymer.
The preparation method of a kind of catechol-derived porous polymer as claimed in claim 8, is characterized in that specifically comprises the following steps:

(1) in the mixed system of the compound described in claim 1 and catalyzer, add solvent, then stir reaction;

(2) Post-processing the mixed solution obtained in step (1) to obtain compound II.
The preparation method of the catechol-derived porous polymer according to any one of claims 8 and 9, wherein the catalyst described in the step (1) is boron tribromide, and the catalyst dosage is the same as that of compound I/IV ( The dosage ratio of IV')/VII is 1 mg (compound I, IV(IV'), VII): 1 mL (boron tribromide) to 500 mg (compound I, IV (IV'), VII): 1 mL (boron tribromide) ).
The method for preparing a catechol-derived porous polymer according to any one of claims 8 and 9, wherein the post-treatment described in the step (2) is: adding water to quench, then filtering, and washing the solid residue ; Among them, washing with organic solvent and water is preferred.
A catechol-derived porous polymer-supported high-spin single-atom iron catalyst is characterized by having the structure of compound III or VI(VI') or IX:

In the compound, R1, R6 are selected from CH and various alkyl chains derived from it, N, O, S; R4, R5, R9 are selected from CH and various alkyl chains derived from CH and its derivatives, N, O, S; n1 , n2 and n3 are integers respectively, and n1+n2+n3>=1; R7 is selected from CH and its derived various alkyl chains, benzene rings, 1,3,5-triazine; R8 is selected from C, C =C, porphyrin; R10, R11 can be two H or one FeCl, thus obtaining the following structural fragments with adjacent groups:

In one of the porous polymer-supported high-spin single-atom iron catalyst structures,
The number is at least 1.
A method for preparing a high-spin single-atom iron catalyst supported by a catechol-derived porous polymer represented by compound III or VI (VI') or IX as claimed in claim 12, characterized in that the structure of claim 7 After the catechol-derived porous polymer is added to the base for reaction, and then the iron source is added for the reaction, the catechol-derived porous polymer supported high-spin single-atom iron catalyst is finally obtained.
The preparation method of a catechol-derived porous polymer-supported high-spin single-atom iron catalyst according to claim 13, characterized in that it specifically comprises the following steps:

(1) the catechol-derived porous polymer with the described structure of claim 7 is dispersed in the solvent, adds alkali, after the reaction, filters and washes, obtains solid powder;

(2) dispersing the solid powder obtained in step (1) in a solvent, then adding an iron source, after the reaction, and post-processing to obtain a catechol-derived porous polymer-supported high-spin single-atom iron catalyst.
The preparation method of the catalyst according to claims 13 and 14, wherein the solvent in the step (1) is ethanol, the base in the step (1) is NaOH, and the compound II/V(V) in the step (1) ')/VIII consumption and the mixed mass ratio of alkali consumption is m(compound II/V(V')/VIII): m (base)=1:0.0001 to 1:1, wherein m is mass; in step (1) The reaction conditions were ultrasonic reaction or magnetic stirring reaction, and washed with ethanol and deionized water.
The preparation method of the catalyst according to claims 13 and 14, wherein the iron source in step ( 2 ) is FeX or its hydrate, X is -Cl or -Br, and the dosage ratio is m (compound II/ V(V')/VIII): m (iron source)=1:0.0001 to 1:1, where m is mass; the reaction conditions described in step (2) are ultrasonic reaction or magnetic stirring reaction, in step (2) The work-up is filtration, and the solid residue is washed with organic solvent and water.
A kind of application in the epoxidation of styrene by utilizing the catalyst obtained by the catalyst described in claim 12 or the preparation method described in claims 13-16, characterized in that: utilizing the catechol derivative described in claim 12 The porous polymer-supported high-spin single-atom iron catalyst or the catechol-derived porous polymer-supported high-spin single-atom iron catalyst obtained by the corresponding preparation method according to claims 13-16, realizes the epoxidation of styrene through an oxygen source under illumination reaction.
The application according to claim 17, characterized in that it comprises: mixing styrene with the catalyst according to claim 12 or the catalyst obtained by the preparation method according to claims 13-16, adding a solvent, reacting with light, sampling and measuring the mixture product yield.
Application as claimed in claim 17, 18, is characterized in that, comprises the following steps:

(1) mixing styrene with the catalyst described in claim 12 or the catalyst obtained by the preparation method described in claims 13-16, and adding a solvent;

(2) Illumination and magnetic stirring at 10-35°C for 6-12h;

(3) The mixture was sampled to determine the product yield.
Application according to claim 17-19 is characterized in that: the solvent described in the step (1) is preferably DMF; the mixed molar ratio described in the step (1) is n (styrene): n (catalyst)=1: 0.01 to 1:0.1, where n is the amount of substance; the yield is preferably determined by a high performance gas mass spectrometer.
The application according to claims 17-19 is characterized in that: the catalyst can be reused for at least 3 cycles without loss of catalytic activity and selectivity.
The application according to claims 17-19, wherein air is used as the oxygen source in the catalytic reaction.