A chloramphenicol-containing organic porous polymer catalyst and a synthesis method and application thereof

Abstract

The application provides a chloramphenicol-containing organic porous polymer catalyst and a synthesis method and application thereof, and belongs to the technical field of organic synthesis. The polymer catalyst comprises intermediates A, B and C, the intermediates A and B are styrene and divinylbenzene isomer mixtures respectively, and the intermediates A, B and C are synthesized through a polymerization reaction under the action of a free radical initiator. The polymer catalyst is a heterogeneous catalyst with a chloramphenicol chiral skeleton structure, can be synthesized by taking industrial waste chloramphenicol as a starting material, has the advantages of low cost, good catalytic efficiency, high enantioselectivity and multiple recycling, etc. The asymmetric catalytic synthesis using the catalyst can separate and recycle the catalyst from the reaction system through a simple filtration operation, has the technical advantages of simple experimental operation steps, recyclable catalyst, etc. The chloramphenicol polymer catalyst has good industrial application prospect when applied to the asymmetric alcoholysis ring-opening of a cyclic anhydride.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, and particularly relates to a chloramphenicol-containing organic porous polymer catalyst, its synthesis method, and its application. Background Technology

[0002] Since mesocyclic cyclic anhydrides are easy to prepare, enantioselective ring-opening reactions of cyclic anhydride intermediates have undoubtedly become an important type of asymmetric synthetic reaction. Furthermore, the asymmetric alcoholysis ring-opening of substrate anhydrides using inexpensive and readily available nucleophilic alcohols can be used to prepare important chiral synthetic intermediates (half-esters or thioesters) in organic synthesis, showing broad application prospects in the asymmetric synthesis of natural products.

[0003] Numerous studies have been reported on the asymmetric catalytic alcoholysis of cyclic anhydrides. However, although traditional homogeneous chiral small molecule catalysts have advantages such as high catalytic activity and good enantioselectivity of products, their synthesis steps are lengthy and they require post-processing to separate from the products after the reaction, which limits their further industrial application.

[0004] The most common solution currently is to use immobilization to address the difficulty in separating homogeneous catalysts from products. However, the catalytic activity of immobilized catalysts is somewhat reduced compared to small-molecule homogeneous catalysts. Therefore, it is necessary to design a novel heterogeneous catalyst with reactivity and enantioselectivity comparable to or even exceeding that of homogeneous catalysts, for use in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. This would enable the acquisition of chiral half-ester products with high yield and high enantioselectivity under heterogeneous reaction conditions, as well as rapid separation and recovery of the catalyst from the product. Summary of the Invention

[0005] The present invention aims to provide a chloramphenicol-containing organic porous polymer catalyst, its synthesis method, and its application. The catalyst comprises intermediates A, B, and C, which are synthesized by polymerization reaction under the action of a free radical initiator at equivalent ratios of 20:0.4:1 or 10:0.2:1, respectively. In the polymer catalyst, intermediate A is styrene; intermediate B is a mixture of 55% by mass of divinylbenzene isomers; and the structural formula of intermediate C is as follows:

[0006]

[0007] The free radical initiator is azobisisobutyronitrile or 2,2-azobis(2-methylpropylimidazolium) hydrochloride; R1 is an aromatic substituent; R2 is an aromatic substituent or an aralkyl substituent.

[0008] Furthermore, when R1 is 4-vinylphenyl, R2 is triphenylmethyl, the free radical initiator is azobisisobutyronitrile, and the equivalent ratio of intermediate A, intermediate B, and intermediate C is 20:0.4:1, or when R1 is 4-vinylphenyl, R2 is triphenylmethyl, the free radical initiator is 2,2-azobis(2-methylpropylimidazolium) hydrochloride, and the equivalent ratio of intermediate A, intermediate B, and intermediate C is 10:0.2:1, intermediate C is intermediate D;

[0009] When R1 is 4-vinylbenzyl, R2 is triphenylmethyl, the free radical initiator is azobisisobutyronitrile, and the equivalent ratio of intermediate A, intermediate B and intermediate C is 20:0.4:1, intermediate C is intermediate E;

[0010] When R1 is 3,5-bis(trifluoromethyl)phenyl, R2 is 4-vinylbenzoyl, the free radical initiator is 2,2-azobis(2-methylpropylimidazolium) hydrochloride, and the equivalence ratio of intermediates A, B, and C is 20:0.4:1, intermediate C is intermediate F.

[0011] The amount of free radical initiator used is the same as the amount of the corresponding intermediate B used.

[0012] Furthermore, when R1 is 4-vinylphenyl and R2 is triphenylmethyl, intermediate C is intermediate D; when R1 is 4-vinylbenzyl and R2 is triphenylmethyl, intermediate C is intermediate E; when R1 is 3,5-bis(trifluoromethyl)phenyl and R2 is 4-vinylbenzoyl, intermediate C is intermediate F.

[0013] Furthermore, the structural formula of intermediate D is expressed as:

[0014]

[0015] The structural formula of intermediate E is expressed as follows:

[0016]

[0017] The structural formula of intermediate F is expressed as follows:

[0018]

[0019] Furthermore, the synthesis steps of intermediate D are as follows:

[0020]

[0021] The specific steps for synthesizing intermediate E are as follows:

[0022]

[0023] The specific steps for synthesizing intermediate F are as follows:

[0024]

[0025] A method for synthesizing an organic porous polymer catalyst, characterized by comprising the following steps:

[0026] S1: Under nitrogen protection, gum arabic and salt are dissolved in deionized water, intermediate D or E or F is dissolved in chlorobenzene, then intermediate A, intermediate B and free radical initiator are added, and then the organic phase and aqueous phase are mixed.

[0027] S2: The reaction mixture is heated to a certain temperature while being continuously stirred. After stirring the reaction, the reaction mixture is cooled to room temperature to obtain the polymer.

[0028] S3: Filter the polymer, and wash the filtered polymer in sequence with methanol, deionized water, methanol and ethanol. After vacuum drying, the polymer catalyst is obtained.

[0029] Furthermore, in S1, there are 1.62 g of gum arabic; 1.1 g of salt; 32.00 mL of deionized water; 1 mmol each of intermediate D, intermediate E, or intermediate F; 3.60 mL of chlorobenzene; 20 mmol of intermediate A, totaling 2.22 mL; 0.4 or 0.2 mmol of intermediate B, totaling 0.06 or 0.03 mL respectively; and 0.4 or 0.2 mmol of the free radical initiator.

[0030] In S2, the specific temperature is 90℃; the stirring reaction time is 24 hours.

[0031] In step S3, the filtered polymer was washed sequentially with 50.00 mL of methanol, 50.00 mL of deionized water, 50.00 mL of methanol, and 50.00 mL of ethanol.

[0032] Furthermore, polymer catalysts are applied to the alcoholysis and ring-opening of cyclic acid anhydrides.

[0033] Furthermore, the alcoholysis of cyclic anhydrides is an asymmetric alcoholysis of cyclic anhydrides.

[0034] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in:

[0035] 1. The chloramphenicol-containing organic porous polymer catalyst provided by this invention has good chemical stability and recyclability. The catalyst can be separated from the reaction system by simple filtration and can be reused multiple times after washing. The experimental operation and post-processing are simple. Furthermore, the optical purity and separation yield of the product are higher than those of the unsupported homogeneous catalyst, which solves the problem of decreased catalytic activity and enantioselectivity of homogeneous catalysts after immobilization. It also has low environmental pollution and good prospects for industrial application.

[0036] 2. The synthesis of the chloramphenicol-containing organic porous polymer catalyst provided by this invention uses chloramphenicol, a byproduct of industrial chloramphenicol production, as a chiral starting material for chemical synthesis. The organic porous polymer catalyst prepared by this inexpensive and readily available chiral source through a simple reaction has the technical advantages of high efficiency, practicality, and low cost. Attached Figure Description

[0037] Figure 1 This is a SEM image of the chloramphenicol-containing organic porous polymer catalyst of the present invention.

[0038] Figure 2 This is a TEM image of the chloramphenicol-containing organic porous polymer catalyst of the present invention in diethyl ether.

[0039] Figure 3 This is an EDS mapping diagram of the chloramphenicol-containing organic porous polymer catalyst of the present invention.

[0040] Figure 4 This is the Fourier transform infrared spectrum of the chloramphenicol-containing organic porous polymer catalyst of the present invention.

[0041] Figure 5 The image shows the XRD pattern of the chloramphenicol-containing organic porous polymer catalyst of this invention.

[0042] Figure 6 The thermogravimetric curve of the chloramphenicol-containing organic porous polymer catalyst of this invention is shown.

[0043] Figure 7 The image shows the hydrogen nuclear magnetic resonance spectrum of intermediate D in this invention.

[0044] Figure 8 This is the carbon NMR spectrum of intermediate D in this invention.

[0045] Figure 9 The above is the hydrogen nuclear magnetic resonance spectrum of intermediate E of this invention.

[0046] Figure 10 This is the carbon NMR spectrum of intermediate E in this invention.

[0047] Figure 11 The image shows the hydrogen nuclear magnetic resonance spectrum of intermediate F in this invention.

[0048] Figure 12 This is the carbon NMR spectrum of intermediate F in this invention. Detailed Implementation

[0049] The following is a more detailed description of a chloramphenicol-containing organic porous polymer catalyst, its synthesis method, and its application, with reference to schematic diagrams. Preferred embodiments of the invention are shown. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0050] A method for synthesizing a chloramphenicol-containing organic porous polymer catalyst includes intermediates A, B, and C. Intermediates A, B, and C are polymerized via a polymerization reaction under the action of a free radical initiator to synthesize the polymer catalyst. The intermediates A, B, and C react in an equivalent ratio of 20:0.4:1 or 10:0.2:1. Intermediate A is styrene, intermediate B is a mixture of 55% by mass of divinylbenzene isomers, and the structural formula of intermediate C is as follows:

[0051]

[0052] Wherein, R1 is an aromatic substituent, and further, the aromatic substituent is 4-vinylphenyl, 4-vinylbenzyl or 3,5-bis(trifluoromethyl)phenyl;

[0053] R2 is an aromatic substituent or an aralkyl substituent. Further, the aromatic substituent is 4-vinylbenzoyl, and the aralkyl substituent is triphenylmethyl.

[0054] The structural formula of intermediate A is as follows:

[0055]

[0056] The structural formula of intermediate B is as follows:

[0057]

[0058] The polymer catalyst of the present invention, its synthesis method and application are further described below through specific embodiments.

[0059] Example 1:

[0060] When R1 is 4-vinylphenyl, R2 is triphenylmethyl, the equivalent ratio of intermediates A, B, and C is 20:0.4:1, and the free radical initiator is azobisisobutyronitrile, intermediate C is intermediate D; furthermore, intermediate D is chemically synthesized from chloramphenicol as a chiral starting material, and the structural formula of intermediate D is as follows:

[0061]

[0062] The specific steps for synthesizing intermediate D are as follows:

[0063]

[0064] The synthesis of intermediate J uses chloramphenicol G, a byproduct of industrial chloramphenicol production, as a chiral starting material and can be carried out according to the methods reported in the literature (Org. Lett., 2002, 4, 3451; Angew. Chem. Int. Ed., 2003, 43, 216; New J. Chem., 2022, 46, 13269).

[0065] Then, (1R,2R)-2-(N,N-dimethylamino)-1-(p-nitrophenyl)-3-triphenylmethoxy-1,2-propanediamine (intermediate J, 2 mmol), triethylamine (8 mmol), and dichloromethane (20 mL) were added sequentially to a round-bottom flask at room temperature. The reaction mixture was cooled to 0°C in an ice-water bath and stirred for 10 min. Then, 4-vinylbenzenesulfonyl chloride (3 mmol, preparation method can be found in the literature: Bull. Chem. Soc. Jpn., 1983, 56, 762) was slowly added dropwise to the reaction mixture over 30 min. The reaction mixture was naturally heated to room temperature and stirred continuously for 2 h, with TLC monitoring during the reaction. After the reaction was completed, the crude product was washed sequentially with water (2 × 20.00 mL) and saturated NaCl solution (2 × 20.00 mL), dried over anhydrous Na2SO4, filtered, and the filtrate was concentrated under reduced pressure to obtain a yellow solid product. The crude product was purified by column chromatography (PE:EA = 2:1) to obtain intermediate D in 70% yield. mp: 188.5-189.5℃; [α] D 25 = +73.6 (c 0.05, CHCl3).

[0066] Figure 7 The following is the proton NMR spectrum of intermediate D, with the specific structural characterization as follows: 11H NMR (400 MHz, CDCl3) δ 7.96 - 7.76 (m, 2H), 7.53 (d, J = 8.4 Hz, 2H), 7.35 (d, J = 8.4 Hz, 2H), 7.24 - 6.97 (m, 17H), 6.68 (dd, J = 17.6, 10.9 Hz, 1H), 5.83 (d, J = 17.6 Hz, 1H), 5.42 (d, J = 10.9 Hz, 1H), 3.93 (d, J = 10.6 Hz, 1H), 3.08 (dd, J = 10.6, 6.1 Hz, 1H), 2.93 (dd, J = 10.6, 3.4 Hz, 1H), 2.70 (ddd, J = 9.9, 6.1, 3.3 Hz, 1H), 2.25 (s, 6H). Figure 8 13C NMR spectrum of intermediate D is shown below, and the specific structural characterization is as follows: 13 13C NMR (100 MHz, CDCl3): δ 143.14, 135.25, 129.15, 128.53, 127.82, 127.26, 126.39, 123.44, 117.73, 87.66, 68.03, 58.05, 56.51, 40.95. Based on the comprehensive analysis of the spectra of Figure 7 and Figure 8 the chemical structure of intermediate D was confirmed.

[0067] The steps for synthesizing the chloramphenicolamine-containing organic porous polymer catalyst are as follows:

[0068] Under nitrogen protection, a certain amount of gum arabic (0.81 g) and sodium chloride (0.55 g) were dissolved in deionized water (16 mL), and then a certain amount of N-((1R,2R)-2-(dimethylamino)-1-(4-nitrophenyl)-3-(trityloxymethyl)propyl)-4-vinylbenzenesulfonamide (intermediate D, 0.5 mmol) was dissolved in chlorobenzene (1.80 mL). Then styrene (intermediate A, 10 mmol), a 55% mass fraction mixture of divinylbenzene isomers (intermediate B, 0.2 mmol), and initiator azobisisobutyronitrile (0.2 mmol) were added. The resulting aqueous and organic solutions were mixed. The obtained reaction mixture was heated to 90 °C under continuous stirring, and after stirring for 24 h, the reaction solution was cooled to room temperature. The polymer was filtered and washed successively with 50 mL of methanol, 50 mL of deionized water, 50 mL of methanol, and 50 mL of ethanol, and finally dried under vacuum to obtain the polymer catalyst. The yield was 77%.

[0069] Example 2

[0070] In this example, the sulfur element analysis of the polymer catalyst in Example 1 was carried out by high-temperature combustion method.

[0071] Organic element content analysis value

[0072]

[0073] Furthermore, Fourier transform infrared spectroscopy (FT-IR) was used in this example to further confirm the successful immobilization of intermediate D. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were also used to investigate the surface morphology, surface elemental distribution, bulk structure, and thermal stability of the polymer catalyst.

[0074] like Figure 1 and Figure 2 As shown, the polymer catalyst exhibits an irregular blocky morphology; Figure 3 This shows that C, O, and S elements are uniformly distributed on the surface of the polymer catalyst, indicating that the polymer catalyst can play a good heterogeneous catalytic role. Figure 4 a shows the infrared absorption peak (1156 cm⁻¹) of symmetric and asymmetric stretching vibrations of sulfone groups on the polymer in Example 1. -1 1341cm -1 ) and the infrared absorption peak of the carbon-hydrogen stretching vibration of the benzene ring on the polymer (2922 cm⁻¹) -1 2848cm -1 This indicates that intermediate D was successfully immobilized and highly polymerized with intermediates A and B; Figure 5 Further evidence shows that the polymer catalyst consists of amorphous particles and is highly polymerized; Figure 6 This shows that the chloramphenicol-containing organic porous polymer catalyst in Example 1 has good thermal stability at temperatures below 250°C and can be applied to most common organic reactions.

[0075] Example 3

[0076] This embodiment investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst of Example 1 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in methyl tert-butyl ether (10.00 mL), and the polymer catalyst of Example 1 (0.05 mmol) was added, with the reaction temperature controlled at 25 °C. Methanol (2.5 mmol) was slowly added dropwise to the reaction system, and the reaction was continued with stirring for 72 h. After the reaction was completed, the reaction solution and polymer catalyst were separated by filtration. The recovered polymer catalyst was then washed sequentially with pure diethyl ether (20.00 mL), methanol (20.00 mL), and ethanol (20.00 mL) to remove product and reactant residues from the catalyst surface. After vacuum drying, it can be recycled as a catalyst again. The washing liquid was combined with the aforementioned supernatant and concentrated under reduced pressure to obtain the corresponding ring-opening product (1S,6R)-6-(methoxycarbonyl)cyclohex-3-ene-1-carboxylic acid, with a yield of 94% and an ee value of 90%. 1 H NMR (400MHz, CDCl3) δ = 4.93 (dd, J = 24.1, 3.6Hz, 2H), 3.67 (s, 3H), 3.05-2.99 (m, 2H), 1.84-1.82 (m, 2H), 1.56-1.51 (m, 2H)ppm; 13 C NMR (100MHz, CDCl3) δ = 179.7, 173.7, 125.1, 125.0, 51.9, 39.6, 39.4, 25.7, 25.5ppm.

[0077] This example compares the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst and intermediate D from Example 1 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment is as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in methyl tert-butyl ether (10.00 mL), intermediate D (0.05 mmol) was added, and the reaction temperature was controlled at 25 °C. Methanol (2.5 mmol, 5 equiv.) was slowly added dropwise to the reaction system, and the reaction was continued with stirring for 60 h. After the reaction was completed, the reaction solution was concentrated under reduced pressure, and the crude product was purified by column chromatography (PE:EA = 4:1) to obtain the corresponding ring-opening product (1S,6R)-6-(methoxycarbonyl)cyclohexyl-3-en-1-carboxylic acid, with a yield of 95% and an ee value of 87%. As the results show, the enantioselectivity of the chloramphenicol-containing organic porous polymer catalyst in Example 1 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides is better than that of intermediate D. It can not only significantly simplify the post-reaction processing steps, but also be reused multiple times by simple filtration recovery.

[0078] Example 4

[0079] This embodiment investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst of Example 1 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (5.00 mL), and the polymer catalyst of Example 1 (0.25 mmol) was added, with the reaction temperature controlled at -10 °C. (E)-2-nitro-3-phenylprop-2-en-1-ol (0.55 mmol, 1.1 equiv.) was slowly added dropwise to the reaction system, and the reaction was continued with stirring for 24 h. After the reaction was complete, the reaction solution and polymer catalyst were separated by filtration. The recovered polymer catalyst was then washed sequentially with pure diethyl ether (20.00 mL), methanol (20.00 mL), and ethanol (20.00 mL) to remove product and reactant residues from the catalyst surface. After vacuum drying, it could be recycled as a catalyst again. The washing solution was combined with the aforementioned supernatant and concentrated under reduced pressure. The crude product was separated and purified by column chromatography (PE:EA = 3:1) to obtain the corresponding ring-opening product (1R,6S)-6-((((E)-2-nitro-3-phenylallyl)oxy)carbonyl)cyclohex-3-en-1-carboxylic acid, with a yield of 87% and an ee value of 99%. 1 HNMR (400MHz, CDCl3): δ=2.35-2.42(m,2H),2.56-2.62(m,2H),3.10-3.16( m,2H),5.17-5.25(m,2H),5.70(s,2H),7.42-7.48(m,5H),8.34(s,1H)ppm; 13 C NMR (100MHz, CDCl3): δ = 25.6, 25.6, 39.5, 39.6, 58.3, 125.0, 125.1, 129.3, 130.1, 130.91, 131.3, 140.2, 145.0, 172.4, 178.9ppm.

[0080] Example 5

[0081] This example investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst recovered in Example 4 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (5.00 mL), and the polymer catalyst recovered in Example 4 (0.25 mmol) was added, with the reaction temperature controlled at -10 °C. (E)-2-nitro-3-phenylprop-2-en-1-ol (0.55 mmol, 1.1 equiv.) was slowly added dropwise to the reaction system, and the reaction was continued with stirring for 24 h. After the reaction was complete, the reaction solution and polymer catalyst were separated by filtration. The recovered polymer catalyst was then washed sequentially with pure diethyl ether (20.00 mL), methanol (20.00 mL), and ethanol (20.00 mL) to remove product and reactant residues from the catalyst surface. After vacuum drying, it could be recycled as a catalyst again. The washing liquid was combined with the aforementioned supernatant and concentrated under reduced pressure. The crude product was purified by column chromatography (PE:EA = 3:1) to obtain the corresponding ring-opening product (1R,6S)-6-((((E)-2-nitro-3-phenylallyl)oxy)carbonyl)cyclohex-3-en-1-carboxylic acid, with a yield of 86% and an ee value of 99%. As the results show, the chloramphenicol-containing organic porous polymer catalyst recovered in Example 4 still exhibits excellent catalytic activity and enantioselectivity in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides.

[0082] Example 6

[0083] This embodiment investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst of Example 1 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (5.00 mL), and the polymer catalyst of Example 1 (0.25 mmol) was added, with the reaction temperature controlled at -10 °C. Propylene alcohol (0.15 mmol, 3 equiv.) was slowly added dropwise to the reaction system, and the reaction was continued with stirring for 12 h. After the reaction was complete, the reaction solution and polymer catalyst were separated by filtration. The recovered polymer catalyst was then washed sequentially with pure diethyl ether (20.00 mL), methanol (20.00 mL), and ethanol (20.00 mL) to remove product and reactant residues from the catalyst surface. After vacuum drying, it can be recycled as a catalyst again. The washing solution was combined with the aforementioned supernatant and concentrated under reduced pressure. The crude product was separated and purified by column chromatography (PE:EA = 4:1) to obtain the corresponding ring-opening product (1S,6R)-6-((prop-2-yn-1-oxy))carbonyl)cyclohex-3-ene-1-carboxylic acid, with a yield of 96% and an ee value of 97%. 1H NMR (400MHz, CDCl3) δ = 5.69 (s, 2H), 4.70 (d, J = 2.5Hz, 2H), 3.10 (dtd, J = 32.7, 6.4,3.6Hz,2H),2.71-2.54(m,2H),2.48(t,J=2.5Hz,1H),2.45-2.26(m,2H). 13 C NMR (126MHz, CDCl3) δ = 179.56, 172.42, 125.06, 125.04, 77.44, 77.31, 77.06, 76.81, 75.05, 52.28, 39.55, 39.34, 25.62, 25.40.

[0084] Example 7

[0085] This embodiment investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst of Example 1 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (5.00 mL), and the polymer catalyst of Example 1 (0.25 mmol) was added, with the reaction temperature controlled at -10 °C. 2,2-diphenylethanol (0.55 mmol, 1.1 equiv.) was slowly added to the reaction system, and the reaction was continued with stirring for 24 h. After the reaction was complete, the reaction solution and polymer catalyst were separated by filtration. The recovered polymer catalyst was then washed sequentially with pure diethyl ether (20.00 mL), methanol (20.00 mL), and ethanol (20.00 mL) to remove product and reactant residues from the catalyst surface. After vacuum drying, it can be recycled as a catalyst again. The washing solution was combined with the aforementioned supernatant and concentrated under reduced pressure. The crude product was separated and purified by column chromatography (PE:EA = 6:1) to obtain the corresponding ring-opening product (1S,6R)-6-((2,2-diphenylethoxy)carbonyl)cyclohex-3-ene-1-carboxylic acid, with a yield of 93% and an ee value of 93%. 1 H NMR (500MHz, CDCl3): δ=2.24-2.30(m,2H),2.41-2.49(m,2H),2.92–2.98(m,2H),4.35(t,J=7.5,1H ),4.62(dd,J=11.0,7.5,1H),4.67(dd,J=11.0,7.5,1H),5.55-5.61(m,2H),7.18-7.29(m,10H)ppm; 13C NMR (125MHz, CDCl3): δ = 25.5, 39.26, 39.34, 49.6, 66.9, 125.0, 125.1, 126.7, 128.1, 128.5, 140.9, 173.0, 179.5ppm.

[0086] Example 8:

[0087] When R1 is 4-vinylphenyl, R2 is triphenylmethyl, the equivalent ratio of intermediates A, B, and C is 10:0.2:1, and the free radical initiator is 2,2-azobis(2-methylpropylimidazolium) hydrochloride, intermediate C is intermediate D; furthermore, intermediate D is chemically synthesized from chloramphenicol as a chiral starting material, and the structural formula of intermediate D is as follows:

[0088]

[0089] The steps for synthesizing chloramphenicol-containing organic porous polymer catalysts are as follows:

[0090] Under nitrogen protection, a certain amount of gum arabic (0.81 g) and sodium chloride (0.55 g) were dissolved in deionized water (16.00 mL), and a certain amount of N-((1R,2R)-2-(dimethylamino)-1-(4-nitrophenyl)-3-(triphenylmethoxy)propyl)-4-vinylbenzenesulfonamide (intermediate D, 0.5 mmol) was dissolved in chlorobenzene (1.80 mL). Then, styrene (intermediate A, 5 mmol), a 55% (w / w) mixture of divinylbenzene isomers (intermediate B, 0.1 mmol), and the initiator 2,2-azobis(2-methylpropylimidazolium) dihydrochloride (0.1 mmol) were added. The resulting aqueous and organic solutions were mixed. The resulting reaction mixture was heated to 90°C under continuous stirring and reacted for 24 hours. The reaction solution was then cooled to room temperature. The polymer was filtered and washed sequentially with 50.00 mL of methanol, 50.00 mL of deionized water, 50.00 mL of methanol, and 50.00 mL of ethanol. Finally, the polymer catalyst was obtained by vacuum drying. The yield was 77%.

[0091] Example 9:

[0092] In this embodiment, the high-temperature combustion method was used to analyze the sulfur content of the polymer catalyst in Example 8.

[0093] Organic element content analysis value

[0094]

[0095] In addition, Fourier transform infrared spectroscopy (FT-IR) was used in this example to further confirm the successful immobilization of intermediate D. Thermogravimetric analysis was also used to investigate the thermal stability of the polymer catalyst in this example.

[0096] like Figure 4 As shown in b, the polymer exhibits infrared absorption peaks at 1156 cm⁻¹ due to the symmetric and asymmetric stretching vibrations of the sulfone group. -1 1341cm -1 ) and the infrared absorption peak of the carbon-hydrogen stretching vibration of the benzene ring on the polymer (2848 cm⁻¹) -1 2922cm -1 This indicates that intermediate D was successfully immobilized and highly polymerized with intermediates A and B; Figure 6 This shows that the chloramphenicol-containing organic porous polymer catalyst has good thermal stability at temperatures below 250°C and can be applied to most common organic reactions.

[0097] Example 10:

[0098] This embodiment investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst of Example 8 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in methyl tert-butyl ether (10.00 mL), and the polymer catalyst of Example 8 (0.05 mmol) was added, with the reaction temperature controlled at 25 °C. Methanol (2.5 mmol, 5 equiv.) was slowly added dropwise to the reaction system, and the reaction was continued with stirring for 60 h. After the reaction was completed, the reaction solution and polymer catalyst were separated by filtration. The recovered polymer catalyst was then washed sequentially with pure diethyl ether (20.00 mL), methanol (20.00 mL), and ethanol (20.00 mL) to remove product and reactant residues from the catalyst surface. After vacuum drying, it could be recycled as a catalyst again. The washing liquid was combined with the aforementioned supernatant and concentrated under reduced pressure to obtain the corresponding ring-opening product (1S,6R)-6-(methoxycarbonyl)cyclohexyl-3-ene-1-carboxylic acid, with a yield of 86% and an ee value of 88%. As the results show, the enantioselectivity of the chloramphenicol-containing organic porous polymer catalyst in Example 8 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides is also superior to that of intermediate D.

[0099] Example 11:

[0100] When R1 is 4-vinylbenzyl, R2 is triphenylmethyl, the equivalent ratio of intermediates A, B, and C is 20:0.4:1, and the free radical initiator is azobisisobutyronitrile, intermediate C is intermediate E; furthermore, intermediate E is chemically synthesized from chloramphenicol as a chiral starting material, and the structural formula of intermediate E is as follows:

[0101]

[0102] The specific steps for synthesizing intermediate E are as follows:

[0103]

[0104] The synthesis of intermediate J uses chloramphenicol G, a byproduct of industrial chloramphenicol production, as a chiral starting material and can be carried out according to the methods reported in the literature (Org. Lett., 2002, 4, 3451; Angew. Chem. Int. Ed., 2003, 43, 216; New J. Chem., 2022, 46, 13269).

[0105] (1R,2R)-2-(N,N-dimethylamino)-1-(p-nitrophenyl)-3-triphenylmethoxy-1,2-propanediamine (intermediate J, 2 mmol), triethylamine (8 mmol), and dichloromethane (20 mL) were added sequentially to a round-bottom flask at room temperature. The reaction mixture was cooled to 0°C in an ice-water bath and stirred for 10 min. Then, 4-vinylphenylmethanesulfonyl chloride (3 mmol, preparation method can be found in patent: WO 2022 / 254012 A1) was slowly added dropwise over 30 min. The reaction mixture was naturally heated to room temperature and stirred continuously for 2 h, with TLC monitoring maintained throughout the reaction. After the reaction was completed, the crude product was washed sequentially with water (2 × 20.00 mL) and saturated NaCl solution (2 × 20.00 mL), dried over anhydrous Na2SO4, filtered, and the filtrate was concentrated under reduced pressure to obtain a yellow solid product. The crude product was purified by column chromatography (PE:EA = 6:1) to obtain intermediate E in 42% yield. mp84.0-85.1℃; [α] D 26 = -206.40 (c 0.05, CH2Cl2).

[0106] Figure 9 The following is the proton NMR spectrum of intermediate E, with the specific structural characterization as follows: 11H NMR (400 MHz, CDCl3) δ = 8.03 (d, J = 8.7 Hz, 2H), 7.27 (d, J = 8.0 Hz, 4H), 7.17 (s, 15H), 7.08 (d, J = 8.2 Hz, 2H), 6.66 (dd, J = 17.6, 10.9 Hz, 1H), 5.73 (d, J = 17.6 Hz, 1H), 5.34–5.19 (m, 1H), 4.31 (d, J = 10.6 Hz, 1H), 3.77 (s, 2H), 3.17 (dd, J = 10.5, 6.2 Hz, 1H), 2.94 (dd, J = 10.5, 3.4 Hz, 1H), 2.82–2.71 (m, 1H), 2.37 (s, 6H). Figure 10 13C NMR spectrum of intermediate E, and the specific structural characterization is as follows: 13 13C NMR (100 MHz, CDCl3): δ = 147.59, 147.54, 143.27, 138.10, 136.18, 130.88, 129.43, 128.60, 127.91, 127.33, 126.46, 123.88, 115.00, 87.75, 67.62, 60.27, 58.51, 56.41, 41.00. Comprehensive analysis of the Figure 9 and Figure 10 spectra confirmed the chemical structure of intermediate E.

[0107] The steps for synthesizing the chloramphenicolamine-containing organic porous polymer catalyst are as follows:

[0108] Under nitrogen protection, a certain amount of gum arabic (0.81 g) and sodium chloride (0.55 g) were dissolved in deionized water (16.00 mL), and then a certain amount of N-((1R,2R)-2-(dimethylamino)-1-(4-nitrophenyl)-3-(trityloxymethyl)propyl)-4-vinylbenzenesulfonamide (intermediate E, 0.5 mmol) was dissolved in chlorobenzene (1.80 mL). Then, styrene (intermediate A, 10 mmol), a 55% mass fraction mixture of divinylbenzene isomers (intermediate B, 0.2 mmol), and the initiator azobisisobutyronitrile (0.2 mmol) were added. The resulting aqueous and organic solutions were mixed. The resulting reaction mixture was heated to 90 °C under continuous stirring, and after stirring for 24 h, the reaction solution was cooled to room temperature. The polymer was filtered and washed successively with 50.00 mL of methanol, 50.00 mL of deionized water, 50.00 mL of methanol, and 50.00 mL of ethanol, and finally obtained the polymer catalyst by vacuum drying. The yield was 74%.

[0109] Example 12:

[0110] In this embodiment, the high-temperature combustion method was used to analyze the sulfur content of the polymer catalyst in Example 11.

[0111] Organic element content analysis value

[0112]

[0113] In addition, Fourier transform infrared spectroscopy (FT-IR) was used in this example to further confirm the successful immobilization of intermediate E. Thermogravimetric analysis (TGA) was also used in this example to study the thermal stability of the polymer catalyst.

[0114] like Figure 4 As shown in c, the polymer catalyst exhibits infrared absorption peaks (1154 cm⁻¹) due to the symmetric and asymmetric stretching vibrations of the sulfone group. -1 1348cm -1 ) and the infrared absorption peak of the carbon-hydrogen stretching vibration of the benzene ring on the polymer (2847 cm⁻¹) -1 2920cm -1 This indicates that intermediate E was successfully immobilized and highly polymerized with intermediates A and B; Figure 6 This shows that the chloramphenicol-containing organic porous polymer catalyst has good thermal stability at temperatures below 250°C and can be applied to most common organic reactions.

[0115] Example 13:

[0116] This embodiment investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst from Example 11 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (20.00 mL), intermediate E (0.25 mmol) was added, and the reaction temperature was controlled at -10 °C. Cinnamyl alcohol (0.55 mmol, 1.1 equiv.) was slowly added to the reaction system, and the reaction was continued with stirring for 24 h. After the reaction was complete, the reaction solution was concentrated under reduced pressure, and the crude product was purified by column chromatography (PE:EA = 4:1) to obtain the corresponding ring-opening product (1S,6R)-6-((cinnamyloxy)carbonyl)cyclohex-3-ene-1-carboxylic acid, with a yield of 95% and an ee value of 94%. 1 H NMR (400MHz, CDCl3) δ = 7.42-7.29 (m, 5H), 6.64 (d, J = 3.2Hz, 2H), 6.41-6.36 (m, 1H), 5.73 (s,2H),4.34-4.33(m,2H),3.14-3.09(m,2H),2.66-2.62(m,2H),2.43-2.39(m,2H)ppm; 13C NMR (100MHz, CDCl3) δ = 177.7, 173.2, 136.7, 131.0, 128.5, 127.6, 126.4, 125.1, 123.1, 65.3, 63.4, 39.7, 39.6, 25.8, 25.6ppm.

[0117] This example compares the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst and intermediate E from Example 11 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment is as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (20.00 mL), intermediate E (0.05 mmol) was added, and the reaction temperature was controlled at -10 °C. Cinnamyl alcohol (0.55 mmol, 1.1 equiv.) was slowly added to the reaction system, and the reaction was continued with stirring for 18 h. After the reaction was completed, the reaction solution was concentrated under reduced pressure, and the crude product was purified by column chromatography (PE:EA = 4:1) to obtain the corresponding ring-opening product (1S,6R)-6-(methoxycarbonyl)cyclohexyl-3-ene-1-carboxylic acid, with a yield of 93% and an ee value of 89%. As the results show, the enantioselectivity of the chloramphenicol-containing organic porous polymer catalyst of Example 11 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides is better than that of intermediate E.

[0118] Example 14:

[0119] When R1 is 3,5-bis(trifluoromethyl)phenyl, R2 is 4-vinylbenzoyl, the equivalence ratio of intermediate A, intermediate B, and intermediate C is 20:0.4:1, and the free radical initiator is 2,2-azobis(2-methylpropylimidazolium) hydrochloride, intermediate C is intermediate F; furthermore, intermediate F is chemically synthesized from chloramphenicol as a chiral starting material, and the structural formula of intermediate F is as follows:

[0120]

[0121] The specific steps for synthesizing intermediate F are as follows:

[0122]

[0123] The synthesis of intermediate H uses chloramphenicol G, a byproduct of industrial chloramphenicol production, as a chiral starting material and can be carried out according to the methods reported in the literature (Org. Lett., 2002, 4, 3451; Angew. Chem. Int. Ed., 2003, 43, 216; New J. Chem., 2022, 46, 13269).

[0124] Then, at room temperature, (1S,2S)-2-(N,N-dimethylamino)-1-(4-nitrophenyl)propane-1,3-diol (intermediate H, 8.32 mmol) and triethylamine (16.65 mmol) were placed in a three-necked flask, dissolved in dichloromethane (50 mL), and the reaction apparatus was sealed and purged three times with N2 to remove air from the reaction system. The three-necked flask was then cooled to 0°C in an ice-water bath. Next, a solution of 4-vinylbenzoyl chloride (9.16 mmol) in dichloromethane (20 mL) was added dropwise. The mixture was then heated to room temperature and stirred for 10 h, with TLC monitoring maintained throughout the reaction. After the reactants had completely reacted, water (10 mL) was added to quench the reaction. The organic phase was then washed three times with water (3 × 15 mL), dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a yellow oily crude product. The crude product can be purified once by column chromatography (PE:EA = 3:1) to obtain intermediate K in 23% yield. [α] D 23 = +31.95 (c 0.12, CH2Cl2). 1 HNMR (400MHz, CDCl3) δ = 8.16 (d, J = 8.8Hz, 2H), 7.75 (d, J = 8.4Hz, 2H), 7.58 (d, J = 8.7Hz, 2H), 7.41 (d, J = 8.3Hz, 2H), 6.73 (dd, J = 17.6, 1 0.9Hz,1H),5.86(d,J=17.6Hz,1H),5.40(d,J=10.9Hz,1H),4.62(d,J=9.8Hz,1H),4.40–4.17(m,2H),2.97–2.84(m,1H),2.56(s,6H). 13 C NMR (100MHz, CDCl3): δ=164.63,148.04,146.70,141.46,134.75,128.71,127.31, 127.12,125.16,122.74,116.00,69.44,67.85,58.49,40.19.HRMS(ESI)m / z:[M+H] + Calculated for C 20 H 22 N2O5 370.1529, found 371.1595.

[0125] Next, (2S,3S)-2-(N,N-dimethylamino)-3-hydroxy-3-(4-nitrophenyl)-4-vinylbenzoate propyl ester (intermediate K, 10 mmol) and Ph3P (12 mmol) were placed in a three-necked flask at room temperature and dissolved in anhydrous tetrahydrofuran (20 mL). The reaction apparatus was sealed and purged three times with N2 to remove air from the reaction system. The three-necked flask was then cooled to 0°C in an ice-water bath. After stirring for 10 min, anhydrous THF (10 mL) solutions of diisopropyl azodicarbonate (12 mmol) and diphenylphosphoazide (12 mmol) were added dropwise. The mixture was then heated to room temperature and stirred for 10 h, with TLC monitoring throughout the reaction. After the reactants had reacted completely, the mixture was heated to 50°C and held for 2 h. Ph3P (12.5 mmol) was then added, and the reaction was stirred for another 2 h. The reaction mixture was cooled to room temperature, and H₂O (1 mL) was added, with stirring continued for 2 h. After the reaction was complete, dichloromethane (50 mL) was added, and the resulting reaction solution was washed three times with water (3 × 20 mL). The organic phase was then dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a reddish-brown oily crude product. The crude product was dissolved in anhydrous THF (50 mL), and an appropriate amount of anhydrous calcium bromide (36 mmol) was added. The mixture was stirred for 5 h until a large amount of white precipitate appeared in the solution. The solution was filtered, and the filtrate was concentrated under reduced pressure to obtain a yellow oily substance. The crude product could be purified once by column chromatography (PE:EA = 2:1) to obtain crude product L. Crude product L can be directly added to the next reaction step.

[0126] Finally, (1R, 2R)-N were added sequentially to the round-bottom flask at room temperature. 2 N 2 Dimethyl-1-(4-nitrophenyl)-3-(4-vinylbenzoyloxy)propane-o-phenylenediamine (intermediate L, 2 mmol), triethylamine (4 mmol), and dichloromethane (20 mL) were reacted. The reaction mixture was cooled to 0 °C in an ice-water bath and stirred for 10 min. Then, 3,5-bis(trifluoromethyl)benzenesulfonyl chloride (3 mmol) was slowly added dropwise to the reaction mixture over 30 min. The reaction mixture was allowed to warm naturally to room temperature and stirred continuously for 6 h. TLC was maintained during the reaction. After the reaction was completed, the crude product was washed successively with water (2 × 20 mL) and saturated NaCl solution (2 × 20 mL), dried over anhydrous Na2SO4, filtered, and the filtrate was concentrated under reduced pressure to obtain a yellow oily product. The crude product was purified by column chromatography (PE:EA = 7:1) to obtain intermediate F in 54% yield. mp 68.4-69.7 °C; [α] D 26 = -86.698 (c 0.05, CH2Cl2).

[0127] Figure 111H NMR spectrum of intermediate F, and the specific structural characterization is as follows: 1 H NMR(400MHz,CDCl3)δ7.91(d,J=8.7Hz,2H),7.88(s,3H),7.70(d,J=8.3Hz,2H),7.40(d,J=8.3Hz,2H),7.26(d,J=8.7Hz,2H),6.73(dd,J=17.6,10.9Hz,1H),5.86(d,J=17.6Hz,1H),5.42(d,J=10.9Hz,1H),4.53(d,J=10.7Hz,1H),4.31-4.10(m,2H),3.04-2.94(m,1H),2.50(s,6H). Figure 12 13C NMR spectrum of intermediate F, and the specific structural characterization is as follows: 13 C NMR(100MHz,CDCl3):δ164.36,146.73,143.24,142.08,141.69,134.67,131.60,131.26,128.66,128.17,126.91,126.42,126.39,125.24,124.93,124.90,124.86,122.65,119.81,116.20,64.69,57.88,55.61,39.69. Comprehensive analysis of Figure 11 and Figure 12 the spectra confirmed the chemical structure of intermediate F.

[0128] The steps for synthesizing the chloramphenicolamine-containing organic porous polymer catalyst are as follows:

[0129] Under nitrogen protection, a certain amount of gum arabic (0.81 g) and sodium chloride (0.55 g) were dissolved in deionized water (16.00 mL), and a certain amount of N-((1R,2R))-2-(dimethylamino)-1-(4-nitrophenyl)-3-((4-vinylbenzoyloxy)propionyl)-3,5-bis(trifluoromethyl)benzenesulfonamide (intermediate F, 0.47 mmol) was dissolved in chlorobenzene (1.80 mL). Then, styrene (intermediate A, 9.4 mmol), a 55% (w / w) mixture of divinylbenzene isomers (intermediate B, 0.188 mmol), and the initiator 2,2-azobis(2-methylpropylimidazolium) dihydrochloride (0.188 mmol) were added. The resulting aqueous and organic solutions were mixed. The resulting reaction mixture was heated to 90°C under continuous stirring and reacted for 24 hours. The reaction solution was then cooled to room temperature. The polymer was filtered and washed sequentially with 50.00 mL of methanol, 50.00 mL of deionized water, 50.00 mL of methanol, and 50.00 mL of ethanol. Finally, the polymer catalyst was obtained by vacuum drying. The yield was 63%.

[0130] Example 15:

[0131] In this embodiment, the high-temperature combustion method was used to analyze the sulfur content of the polymer catalyst in Example 14.

[0132] Organic element content analysis value

[0133]

[0134] Furthermore, Fourier transform infrared spectroscopy (FT-IR) was used in this example to further confirm the successful immobilization of intermediate F. Thermogravimetric analysis (TGA) was also used in this example to investigate the thermal stability of the polymer catalyst.

[0135] like Figure 4 As shown in Figure d, the polymer exhibits infrared absorption peaks (1140 cm⁻¹) due to the symmetric and asymmetric stretching vibrations of the sulfone group. -1 1352cm -1 ) and the infrared absorption peak of the carbon-hydrogen stretching vibration of the benzene ring on the polymer (2850 cm⁻¹) -1 2920cm -1 This indicates that intermediate F was successfully immobilized and highly polymerized with intermediates A and B; Figure 6 This shows that the chloramphenicol-containing organic porous polymer catalyst has good thermal stability at temperatures below 250°C and can be applied to most common organic reactions.

[0136] Example 16:

[0137] This example investigated the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst from Example 14 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment was as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (20.00 mL), and the polymer catalyst from Example 14 (0.25 mmol) was added, with the reaction temperature controlled at -10°C. Cinnamyl alcohol (0.55 mmol, 1.1 equiv.) was slowly added to the reaction system, and the reaction was continued with stirring for 30 h. After the reaction was complete, the reaction solution was concentrated under reduced pressure, and the crude product was purified by column chromatography (PE:EA = 4:1) to obtain the corresponding ring-opening product (1S,6R)-6-((cinnamyloxy)carbonyl)cyclohex-3-en-1-carboxylic acid, with a yield of 94% and an ee value of 96%.

[0138] This example compares the catalytic activity of the chloramphenicol-containing organic porous polymer catalyst and intermediate F from Example 14 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides. The specific experiment is as follows: cis-1,2,3,6-tetrahydrophthalic anhydride (0.5 mmol) was dissolved in diethyl ether (20.00 mL), intermediate F (0.05 mmol) was added, and the reaction temperature was controlled at -10 °C. Cinnamyl alcohol (0.55 mmol, 1.1 equiv.) was slowly added to the reaction system, and the reaction was continued with stirring for 20 h. After the reaction was completed, the reaction solution was concentrated under reduced pressure, and the crude product was purified by column chromatography (PE:EA = 4:1) to obtain the corresponding ring-opening product (1S,6R)-6-(methoxycarbonyl)cyclohexyl-3-ene-1-carboxylic acid, with a yield of 95% and an ee value of 92%. As the results show, the enantioselectivity of the chloramphenicol-containing organic porous polymer catalyst of Example 14 in the asymmetric alcoholysis ring-opening reaction of cyclic anhydrides is better than that of intermediate F.

[0139] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. The application of a chloramphenicol-containing organic porous polymer catalyst in the ring-opening of cyclic acid anhydrides through alcoholysis, characterized in that, The cyclic anhydride alcoholysis ring-opening is an asymmetric cyclic anhydride alcoholysis ring-opening. The polymer catalyst includes intermediates A, B, and C. Intermediates A, B, and C are synthesized by polymerization reaction in the presence of a free radical initiator at an equivalence ratio of 20:0.4:

1. In the polymer catalyst, intermediate A is styrene; intermediate B is a mixture of 55% by mass of divinylbenzene isomers; and intermediate C is a compound with the following structural formula: D, E, or F. ； Compounds D, E, or F are chemically synthesized using chloramphenicol as a chiral starting material.

2. The application according to claim 1, characterized in that, The free radical initiator is azobisisobutyronitrile or 2,2-azobis(2-methylpropylimidazolium) hydrochloride.

3. The application according to claim 1, characterized in that, The specific steps for synthesizing compound D are as follows: ； The specific steps for synthesizing compound E are as follows: ； The specific steps for synthesizing compound F are as follows: 。 4. The application according to any one of claims 1-3, characterized in that, The synthesis method of the polymer catalyst includes the following steps: S1: Under nitrogen protection, gum arabic and salt are dissolved in deionized water, compound D or E or F is dissolved in chlorobenzene, then intermediate A, intermediate B and free radical initiator are added, and then the organic phase and aqueous phase are mixed. S2: The reaction mixture is heated to a certain temperature while being continuously stirred. After stirring the reaction, the reaction mixture is cooled to room temperature to obtain the polymer. S3: Filter the polymer, and wash the filtered polymer sequentially with methanol, deionized water, methanol and ethanol, and then dry it under vacuum to obtain the polymer catalyst.

5. The application according to claim 4, characterized in that, In S1, the amount of gum arabic is 1.62 g; the amount of salt is 1.1 g; the amount of deionized water is 32.00 mL; the amount of compounds D, E, or F is 1 mmol each; the amount of chlorobenzene is 3.60 mL; the amount of intermediate A is 20 mmol, totaling 2.22 mL; the amount of intermediate B is 0.4 mmol, totaling 0.06 mL; and the amount of free radical initiator is 0.4 mmol. In step S2, the specific temperature is 90℃; the stirring reaction time is 24 hours. In step S3, the filtered polymer is washed sequentially with 50.00 mL of methanol, 50.00 mL of deionized water, 50.00 mL of methanol, and 50.00 mL of ethanol.

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