An endo-type chiral polymer and a preparation method and application thereof

Abstract

This invention belongs to the field of asymmetric catalysis technology, specifically relating to an involute chiral polymer, its preparation method, and its applications. The preparation method of the involute chiral polymer includes the following steps: dissolving a trimesinamide derivative and trimesinylpyridinamide, ultrasonically dispersing, stirring to obtain co-assembled micelles, adding a crosslinking agent, stirring the reaction, centrifuging, washing the precipitate, and drying to obtain the involute chiral polymer. The involute chiral polymer obtained by this invention possesses nanocavities and a coiled structure, which can effectively improve the catalytic conversion rate and stereoselectivity in asymmetric catalytic reactions, solving the problem that chiral catalysis struggles to simultaneously achieve both reaction rate and selectivity. Furthermore, the preparation method of this invention is simple and easily controlled, and the obtained involute chiral polymer exhibits high structural stability, showing promising industrial application prospects in asymmetric catalysis, chiral resolution, and selective adsorption.

Description

Technical Field

[0001] This invention belongs to the field of asymmetric catalysis technology, specifically relating to an involute chiral polymer, its preparation method, and its application. Background Technology

[0002] Chiral molecules play a vital role in living organisms; most natural organisms closely related to life activities are chiral molecules, such as amino acids, ribonucleotides, and sugars. With the continuous development of modern society, the demand for chiral substances in various fields such as medicine, pesticides, materials science, and information science is growing rapidly. Therefore, the efficient synthesis of chiral substances has received widespread attention. At the same time, scientists have recognized that different configurations of a pair of chiral molecules can cause drastically different effects on taste, smell, and even pharmacology, and have begun to pursue the acquisition of chiral-specific products.

[0003] Asymmetric catalytic synthesis is the most efficient method for obtaining chiral substances, and many research teams have conducted studies in both homogeneous and heterogeneous catalysis. Chiral thiourea catalysts, chiral phosphoric acid catalysts, and other small organic molecule catalysts, as well as chiral rhodium and ruthenium metal catalysts, are often used as homogeneous catalysts in organic systems, and significant progress has been made in terms of conversion and stereoselectivity. For example, Dongxin Zhang et al. reported a cinchona bark thiourea catalyst catalyzing the asymmetric Aldol reaction of β-keto esters and indigo to prepare δ-hydroxy-β-keto esters, yielding a highly enantioselective product (Organic Letters 2020, 22, 6-10). Although homogeneous chiral catalysts have made significant progress, they suffer from problems such as difficult recovery, low conversion efficiency, long reaction times, and a tendency to induce side reactions, limiting their substrate scope and applicability.

[0004] Chiral porous materials, due to their fixed pore structure and ordered arrangement of catalytic sites, have exhibited excellent performance in asymmetric catalysis. To date, chiral porous catalysts mainly include several categories such as chiral covalent organic frameworks (COFs), metal-organic frameworks (MOFs), and metal cages (MOCs), demonstrating good performance in catalyzing important organic reactions such as asymmetric Aldol condensation, Michael addition, and Diels-Alder reactions, with significant improvements in conversion rate and stereoselectivity. For example, Yong Cui reported a chiral MOF material capable of catalyzing the asymmetric Aldol reaction of aromatic aldehydes and alkyl ketones (Angew. Chem. Int. Ed. 2014, 53, 13821-13825). Although this porous material has certain advantages in catalytic conversion rate, the introduction of chiral groups into the pore surface disrupts the ordered structure of the porous material, leading to decreased stability. Further methods to improve catalytic selectivity need to be explored. Simultaneously improving reaction rate and catalytic selectivity solely through topological chiral porous structure is difficult to achieve. Therefore, this invention introduces a method to further improve the stereoselectivity of chiral catalysis through the distortion effect of the pore surface structure, broaden the types of porous chiral catalysts, enrich the preparation methods of porous materials, and provide a feasible solution for improving the catalytic conversion efficiency and stereoselectivity of chiral catalysts. Summary of the Invention

[0005] This invention aims to provide an involute chiral polymer, its preparation method, and its applications. The involute chiral polymer prepared by this invention possesses nanocavities and a coiled structure, which can effectively improve the catalytic conversion rate and stereoselectivity in asymmetric catalytic reactions, solving the problem that chiral catalysis struggles to simultaneously achieve both reaction rate and selectivity.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for preparing an involute chiral polymer, comprising the following steps:

[0007] The pyromellitic amide derivative and pyromellitic pyridylamine were dissolved, ultrasonically dispersed, and stirred to obtain co-assembled micelles. A crosslinking agent was added, the mixture was stirred and reacted, centrifuged, and the precipitate was washed and dried to obtain an involute chiral polymer.

[0008] Preferably, the co-assembled micelles are co-assembled precursor structures with different structures formed by intermolecular hydrogen bonding of FTMPTA and TMPTA.

[0009] Preferably, the method for preparing the involute chiral polymer includes at least one of the following (1) to (8):

[0010] (1) The molar ratio of the trimesoamide derivative and trimesoylpyridinium is 1:(1-9);

[0011] (2) The concentration of the pyromellitic methyl methacrylate derivative in the system is 0.05–2 mg / ml;

[0012] (3) The solvent for dissolving the trimesoamide derivative and trimesoylpyridinium amide includes one of acetonitrile, dioxane, acetone and N,N'-dimethylformamide;

[0013] (4) The stirring time is 1 to 2 hours;

[0014] (5) The crosslinking agent is 1,4-dibromomethylbenzene, and the molar ratio of the crosslinking agent to pyromellitic pyridylamine is (1-2.5):1;

[0015] (6) The stirring reaction takes 2 to 7 days and the temperature is 25 to 30°C;

[0016] (7) The washing conditions are washing with dioxane 2 to 3 times;

[0017] (8) The drying temperature is 30-35℃.

[0018] Preferably, the preparation method of the pyromellitic pyridylamine includes the following steps:

[0019] Tristyric acid, 3-aminomethylpyridine, and an auxiliary agent were reacted in solvent a by stirring, followed by rotary evaporation and purification to obtain pyromellitic acid pyridine.

[0020] Preferably, the method for preparing the pyromellitic pyridylamine includes at least one of the following (1) to (2):

[0021] (1) The molar ratio of the pyromellitic acid to 3-aminomethylpyridine is 1:(2-3);

[0022] (2) The stirring reaction time is 3 to 7 hours.

[0023] Preferably, the preparation method of the trimesoamide derivative includes the following steps:

[0024] Preparation of S1, proline chiral catalytic unit:

[0025] 4-(bromomethyl)benzylcarbamate tert-butyl ester and N-Boc-trans-4-hydroxy-D-proline methyl ester were dissolved in solvent a, a catalyst was added, the reaction was stirred, rotary evaporated, and purified to obtain intermediate A. Intermediate A and trifluoroacetic acid were stirred in an ice-water bath in solvent b, rotary evaporated, and purified to obtain proline chiral catalytic unit.

[0026] S2. Preparation of trimesoamide derivatives:

[0027] Tristyric acid, 3-aminomethylpyridine, and an auxiliary agent were reacted in solvent a by stirring, followed by rotary evaporation and purification to obtain intermediate B. Intermediate B, the proline chiral catalytic unit obtained in step S1, and the auxiliary agent were reacted in solvent a by stirring, followed by rotary evaporation and purification to obtain intermediate C. Intermediate C and an inorganic base were reacted in solvent c by stirring, rotary evaporation, and purification to obtain the pyromellitic acid derivative.

[0028] More preferably, the method for preparing the trimesoamide derivative includes at least one of the following (1) to (8):

[0029] (1) The molar ratio of tert-butyl 4-(bromomethyl)benzylcarbamate and N-Boc-trans-4-hydroxy-D-proline methyl ester in step S1 is 1:(1-2).

[0030] (2) The catalyst mentioned in step S1 is sodium hydride;

[0031] (3) The molar ratio of the catalyst to tert-butyl 4-(bromomethyl)benzylcarbamate in step S1 is (1-2):1;

[0032] (4) The molar amount of trifluoroacetic acid in step S1 is 700 eq of intermediate A, and the volume of solvent b is 3 times the volume of trifluoroacetic acid.

[0033] (5) The molar ratio of the proline chiral catalytic unit and intermediate B in step S2 is 1:(1~2);

[0034] (6) The stirring reaction time in steps S1 and S2 is 3 to 7 hours;

[0035] (7) The inorganic base mentioned in step S2 is a sodium hydroxide aqueous solution with a concentration of 1 mol / L;

[0036] (8) The molar ratio of the inorganic base to the intermediate C in step S2 is 5:1.

[0037] Preferably, the method for preparing the involute chiral polymer includes at least one of the following (1) to (5):

[0038] (1) The solvent a is N,N'-dimethylformamide;

[0039] (2) The adjuvants include N,N'-diisopropylethylamine and benzotriazole tetramethylurea hexafluorophosphate;

[0040] (3) Solvent b is dichloromethane;

[0041] (4) The solvent c is one of methanol and ethanol;

[0042] (5) The purification is carried out by column chromatography, wherein the packing material of the column chromatography is one of silica gel or neutral alumina, and the eluent is at least one of methanol, dichloromethane, ethyl acetate, and petroleum ether.

[0043] This invention also claims protection for an involute chiral polymer prepared by the method described above, wherein the prepared involute chiral polymer has an internal cavity of 50–500 nm. The internal cavity can effectively enrich the reaction substrate, induce a confinement effect in the catalyst cavity, and enhance the catalytic conversion rate of the reaction.

[0044] The present invention also claims protection for the application of the aforementioned involute chiral polymer in the fields of selective catalytic Aldol reaction, chiral resolution, and selective adsorption.

[0045] Preferably, the application of the involute chiral polymer in the selective catalytic Aldol reaction includes the following steps:

[0046] The involute chiral polymer was dispersed in a mixed solvent of organic solvent and water, and trifluoroacetic acid. Alkyl ketones and substituted benzaldehydes were added, and the mixture was reacted at room temperature for 3-4 days to obtain the Aldol condensation product.

[0047] More preferably, the application of the involute chiral polymer in the selective catalytic Aldol reaction includes at least one of the following (1) to (5):

[0048] (1) The organic solvent includes at least one of N,N'-dimethylformamide and dimethyl sulfoxide;

[0049] (2) The volume ratio of the organic solvent to water is 4:1;

[0050] (3) The amount of trifluoroacetic acid added is 20 mol% of the amount of benzaldehyde substituted;

[0051] (4) The alkyl ketones include at least one of cyclohexanone, cyclopentanone, and acetone;

[0052] (5) The substituted benzaldehyde includes at least one of 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, and 4-cyanobenzaldehyde.

[0053] The structural formulas of the trimellitylamine (TMPTA) and trimellitylamine derivative (FTMPTA) prepared in this invention are shown below:

[0054]

[0055] This invention uses TMPTA and FTMPTA, which have structural asymmetry, as reactants. Through intermolecular hydrogen bonding between FTMPTA and TMPTA, a chiral proline catalytic group is embedded into the backbone of an involute vesicular polymer, forming an asymmetric precursor—supramolecular micelles (co-assembled micelles). Subsequently, under the action of a crosslinking agent, a polymerization reaction occurs, inducing asymmetric electrostatic repulsion at the micelle interface, resulting in surface curling of the micelles, ultimately yielding a vesicular involute chiral polymer. During the polymerization reaction, the carbon of the bromomethyl group in the crosslinking agent forms a quaternary ammonium salt with the pyridine nitrogen on the micelle ring. The difference in charge distribution at the upper and lower ends of the six-membered ring of the co-assembled micelles causes asymmetric interactions on the ring. During polymerization, the structure gradually curls, increasing the curvature of the chiral site backbone, thereby further improving the stereoselectivity of the obtained involute chiral polymer in asymmetric catalytic reactions.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] (1) In this invention, template polymerization is used to prepare involute chiral polymers, so that the structure of the colloid is maintained before and after polymerization, and polymers with ordered catalytic sites are obtained, thus expanding the synthesis method of chiral polymers.

[0058] (2) In this invention, a series of chiral precursors (TMPTA, FTMPTA) are prepared by co-assembly in solution. The polymerization of asymmetric structures induces involution of the structure, increases the curvature of the chiral site skeleton, and further improves the stereoselectivity of asymmetric catalytic reactions.

[0059] (3) The method for preparing involute chiral polymers provided by this invention is simple, unique, easy to control, and has high polymer structural stability. It has good industrial application prospects in the fields of asymmetric catalysis, chiral resolution, and selective adsorption. Attached Figure Description

[0060] Figure 1 The images show the proton NMR spectrum, carbon NMR spectrum, and electrospray ionization mass spectrum of the FTMPTA obtained in this embodiment of the invention.

[0061] Figure 2 This is a pXRD data diagram of the co-assembled colloid prepared by FTMPTA and TMPTA in Example 1 of the present invention.

[0062] Figure 3 The results are VPO test results for the co-assembled colloids prepared by FTMPTA and TMPTA in Example 1 of this invention.

[0063] Figure 4 This is a schematic diagram of the structure of the involute chiral polymer of the present invention.

[0064] Figure 5These are TEM images of the involute chiral polymers obtained in Examples 1(a), 3(b), and 2(c) of the present invention.

[0065] Figure 6 The X-ray photoelectron spectra of the N1s and Br3d orbitals of the involute chiral polymer prepared in Example 1 of this invention are shown.

[0066] Figure 7 This is an FT-IR data image of the involute chiral polymer obtained in Example 1 of the present invention.

[0067] Figure 8 The results of chiral HPLC testing of the polymer prepared in Example 3 of this invention are shown.

[0068] Figure 9 This is a graph showing the conversion rate and enantiomeric excess value of the products in each reaction system of Experimental Example 1 of the present invention. Detailed Implementation

[0069] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0070] Unless otherwise specified, the experimental methods used in the examples and comparative examples are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0071] The preparation methods of TMPTA and FTMPTA in the embodiments and comparative examples of this invention are as follows:

[0072] Synthesis method of TMPTA:

[0073] Tris(2.4 mmol) and 3-aminomethylpyridine (0.78 g, 7.2 mmol) were uniformly dispersed in 60 mL of N,N'-dimethylformamide. N,N-diisopropylethylamine (0.93 g, 7.2 mmol) was added, and the mixture was stirred for 10 minutes. Then, benzotriazole tetramethylurea hexafluorophosphate (2.73 g, 7.2 mmol) was added, and the mixture was stirred for another 3 hours. The reaction was then stopped, and the solvent N,N-dimethylformamide was removed by rotary evaporation. The mixture was purified by column chromatography using a mixture of dichloromethane and methanol in a volume ratio of 10:1 to obtain 1.03 g of white solid TMPTA (yield 90%).

[0074] Synthesis method of FTMPTA:

[0075] Preparation of S1, proline chiral catalytic unit:

[0076] N-Boc-trans-4-hydroxy-D-proline methyl ester (0.5 g, 2.04 mmol) was dissolved in 20 mL of N,N'-dimethylformamide. Sodium hydride (97.8 mg, 2.45 mmol) was added under ice bath stirring. After stirring for 30 minutes, tert-butyl 4-(bromomethyl)benzylcarbamate (0.51 g, 1.70 mmol) was added. The reaction was continued under ice bath stirring for 5 hours and then stopped. The solvent was removed by rotary evaporation. The intermediate was purified by column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent. Silica gel was used as the packing material to obtain a colorless, transparent, oily intermediate A (0.3 g, 30% yield). Intermediate A was dissolved in 102 mL of dichloromethane. Trifluoroacetic acid (34 mL, 0.45 mol) was added dropwise under ice bath stirring. The reaction was continued under ice bath stirring for 5 hours and then stopped. The solvent was removed by rotary evaporation, and the product was purified by column chromatography using a mixed solvent of dichloromethane and methanol in a volume ratio of 5:1 as the eluent. Neutral alumina was selected as the packing material to obtain a pale yellow, transparent, oily chiral proline catalytic unit (0.26 g, yield 82%).

[0077] Preparation of S2 and FTMPTA:

[0078] Tristyric acid (0.5 g, 2.4 mmol) and 3-aminomethylpyridine (0.52 g, 4.8 mmol) were uniformly dispersed in 60 mL of N,N'-dimethylformamide. N,N'-diisopropylethylamine (0.62 g, 4.8 mmol) was added, and the mixture was stirred for 30 minutes. Then, benzotriazole tetramethylurea hexafluorophosphate (1.82 g, 4.8 mmol) was added, and the mixture was stirred for another 3 hours. The reaction was then stopped, and the solvent N,N'-dimethylformamide was removed by rotary evaporation. The mixture was purified by column chromatography using silica gel as the packing material. The elution solvent was a mixture of dichloromethane and methanol in a volume ratio of 3:1. 0.28 g of a white or pale yellow solid was obtained, which was intermediate B (yield 30%).

[0079] Intermediate B (0.21 g, 0.54 mmol) and proline chiral catalytic unit (0.26 g, 0.53 mmol) were dispersed in 40 mL of N,N'-dimethylformamide. N,N'-diisopropylethylamine (0.14 g, 1.06 mmol) was added and stirred for 30 minutes. Then, benzotriazole tetramethylurea hexafluorophosphate (0.40 g, 1.06 mmol) was added and stirred for another 3 hours. The reaction was then stopped, and the solvent N,N'-dimethylformamide was removed by rotary evaporation. The product was purified by column chromatography using silica gel as the packing material. The elution solvent was a mixture of dichloromethane and methanol in a volume ratio of 8:1, yielding 0.17 g of a white or pale yellow solid, which was intermediate C (yield 50%).

[0080] Intermediate C (0.17 g, 0.27 mmol) was dissolved in 34 mL of methanol, and 0.27 mL of 1 M sodium hydroxide aqueous solution was added. The mixture was stirred at room temperature for 3 hours. After the reaction was completed, 1 M hydrochloric acid solution was added to adjust the pH of the system to 7. Methanol and water were removed by rotary evaporation, and the product was purified by column chromatography using silica gel as the packing material. The elution solvent was a mixed solvent with a volume ratio of dichloromethane:methanol = 2:1, yielding 0.12 g of a white or pale yellow solid, which was FTMPTA (yield 75%).

[0081] The proton NMR spectrum, carbon NMR spectrum, and electrospray ionization mass spectrum of the prepared FTMPTA are attached. Figure 1 As shown, the spectral data is as follows:

[0082] 1 H-NMR (400MHz, DMSO-d6) δ9.38(t,J=5.8Hz,2H),9.29(t,J=5.8Hz,1H),8.58(d,J=1.9Hz,2H),8.49(s,3H),8.47(dd,J=4 .8,1.9Hz,2H),7.75(dt,J=8.0,1.9Hz,2H),7.40-7.35(m,2H),7.35-7.24(m,4H),4.53(d,J=5.8Hz,4H),4.49(d,J=5.8Hz 2H),4.47(s,2H),4.20-4.13(m,1H),3.73(t,J=8.8Hz,1H),3.26-3.23(m,1H),3.20-3.13(m,1H),2.26(m,1H),1.88(m,1H);

[0083] 13 C-NMR (100MHz, CD4O-d4) δ172.6,167.2,167.0,148.2,147.5,138.3,136.7,136.4,135.4, 135.2,135.0,128.9,128.7,127.8,127.4,123.9,77.6,70.3,60.1,50.6,43.1,40.8,35.1;

[0084] ESI-MS: m / z calculated for C 34 H 34 N6O6[M+H] + ,623.25;found:[M+H] + ,623.68.

[0085] Example 1: Preparation of the involute chiral polymer of the present invention

[0086] FTMPTA (1 mg, 1.61 μmol) and TMPTA (3.86 mg, 8.05 μmol) were dispersed in 2 mL of acetonitrile (ACN). After ultrasonic dispersion, the mixture was stirred at room temperature for 1 hour to obtain a co-assembled colloid. 1,4-Dibromomethylbenzene (3.61 mg, 13.69 μmol) was added, and the mixture was stirred at room temperature to crosslink the micelles and form a polymer. The reaction was monitored by thin-layer chromatography until the monomers were completely reacted. The supernatant was removed by centrifugation, and the resulting solid was washed three times with dioxane until no reactant residue remained. The solid was dried at 35 °C to obtain an involute chiral polymer (P-ACN-1:5).

[0087] Example 2: Preparation of the involute chiral polymer of the present invention

[0088] FTMPTA (1 mg, 1.61 μmol) and TMPTA (6.96 mg, 14.49 μmol) were dispersed in 2 mL of acetonitrile and ultrasonically dispersed until homogeneous. The mixture was stirred at room temperature for 2 hours to obtain a co-assembled colloid. 1,4-Dibromomethylbenzene (6.16 mg, 23.35 μmol) was added, and the mixture was stirred at room temperature to crosslink the micelles and form a polymer. The reaction was monitored by thin-layer chromatography until the monomers were completely reacted. The supernatant was removed by centrifugation, and the resulting solid was washed three times with dioxane until no reactant residue remained. The solid was dried at 35 °C to obtain an involute chiral polymer (P-ACN-1:9).

[0089] Example 3: Preparation of the involute chiral polymer of the present invention

[0090] FTMPTA (1 mg, 1.61 μmol) and TMPTA (0.77 mg, 1.61 μmol) were dispersed in 2 mL of dioxane and ultrasonically dispersed until homogeneous. The mixture was stirred at room temperature for 2 hours to obtain a co-assembled colloid. 1,4-Dibromomethylbenzene (1.06 mg, 4.03 μmol) was added, and the mixture was stirred at room temperature to crosslink the micelles and form a polymer. The reaction was monitored by thin-layer chromatography until the monomers were completely reacted. The supernatant was removed by centrifugation, and the resulting solid was washed twice with dioxane until no reactant residue remained. The solid was dried at 30 °C to obtain an involute chiral polymer (P-DIO-1:1).

[0091] Comparative Example 1

[0092] TMPTA (10 mg, 20.81 μmol) was dispersed in 5 mL of acetonitrile and ultrasonically dispersed until homogeneous. The mixture was stirred at room temperature for 1 hour to obtain a self-assembled colloid. 1,4-Dibromomethylbenzene (8.24 mg, 31.22 μmol) was added, and the mixture was stirred at room temperature to allow micelle crosslinking to form a polymer. The reaction was monitored by thin-layer chromatography until the monomer reaction was complete. The supernatant was removed by centrifugation, and the resulting solid was repeatedly washed three times with dioxane until no reactive raw material residue remained. The solid was dried at 35 °C to obtain the polymer (P-ACN).

[0093] Comparative Example 2

[0094] Compared with Example 1, the only difference in this comparative example is that the molar ratio of FTMPTA to TMPTA is 1:10.

[0095] The preparation method is the same as in Example 1, and the polymer (P-ACN-1:10) was obtained.

[0096] Experimental Example 1: Catalytic Effect Test

[0097] Using 4-nitrobenzaldehyde and cyclohexanone as substrates, the catalytic effects of the involute chiral polymers and FTMPTA prepared in Examples 1-3 and Comparative Examples 1-2 were analyzed. The specific methods are as follows:

[0098] The catalysts of each group were dispersed in a mixed solvent of N,N'-dimethylformamide (DMF) and water (DMF / H2O = 4 / 1, v / v). Cyclohexanone (102 μL, 1 mmol) and trifluoroacetic acid (0.5 μL, 6.6 μmol) were added, and the mixture was magnetically stirred at room temperature for 15 minutes. 4-nitrobenzaldehyde (5 mg, 33 μmol) was added, and stirring was continued at room temperature. After four days of reaction, stirring was stopped, and the solvent was removed by vacuum distillation to concentrate the organic phase. The sample was dissolved in a normal phase solvent (n-Hexane / i-PrOH = 9 / 1, v / v, HPLC grade), and injected into a high-performance liquid chromatograph to analyze the conversion rate of the reaction system and the enantiomeric excess value (ee) of the product.

[0099] The separation conditions for high performance liquid chromatography were as follows: the chiral stationary phase was an AD-H (Daicel, 250 mm × 4.6 mm, 5 μm) chiral column; the mobile phase was n-hexane / isopropanol = 9 / 1 (v / v, HPLC grade); the flow rate was 1 mL / min; the injection volume was 20 μL; and the column temperature was 25 °C.

[0100] The conversion rates of the resulting reaction system and the enantiomeric excess values ​​of the products are shown in the attached figure. Figure 9 As shown, the polymer prepared in Comparative Example 1 has poor catalytic reaction due to the absence of chiral catalytic units, with ee%≈0, and cannot achieve the purpose of catalytic reaction.

[0101] From the appendix Figure 9 As can be seen from the examples 1-3 of this invention, the involute chiral polymers can achieve high catalytic efficiency and stereoselectivity. Compared with the homogeneous catalytic reaction system (FTMPTA conversion rate of 63%), the conversion rate can be increased to 92%. At the same time, due to the curling of the involute chiral polymer structure, its stereoselectivity is further improved, from the original 93.3% to 97.78%.

[0102] In Comparative Example 2, the molar ratio of TMPTA to FTMPTA was not suitable, resulting in the catalytic performance and stereoselectivity of the obtained involute chiral polymer being significantly worse than those in the Example.

[0103] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for preparing an involute chiral polymer, characterized in that, Includes the following steps: The pyromellitic pyromellitic amide derivative and pyromellitic pyridylamine were dissolved, ultrasonically dispersed, and stirred to obtain co-assembled micelles. A crosslinking agent was added, the reaction was stirred, centrifuged, the precipitate was washed, and dried to obtain an involute chiral polymer. The molar ratio of the trimesoamide derivative and trimesoylpyridinium is 1:(1-9); The crosslinking agent is 1,4-dibromomethylbenzene; The preparation method of the pyromellitic pyridylamine includes the following steps: Tristyric acid, 3-aminomethylpyridine, and an auxiliary agent were stirred and reacted in solvent a, then rotary evaporated and purified to obtain pyromellitic acid pyridineamine. The preparation method of the pyromellitic amide derivative includes the following steps: Preparation of S1, proline chiral catalytic unit: 4-(bromomethyl)benzylcarbamate tert-butyl ester and N-Boc-trans-4-hydroxy-D-proline methyl ester were dissolved in solvent a, a catalyst was added, the reaction was stirred, rotary evaporated, and purified to obtain intermediate A. Intermediate A and trifluoroacetic acid were stirred in an ice-water bath in solvent b, rotary evaporated, and purified to obtain proline chiral catalytic unit. S2. Preparation of trimesoamide derivatives: Tristyric acid, 3-aminomethylpyridine, and an auxiliary agent were reacted in solvent a by stirring, followed by rotary evaporation and purification to obtain intermediate B. Intermediate B, the proline chiral catalytic unit obtained in step S1, and the auxiliary agent were reacted in solvent a by stirring, followed by rotary evaporation and purification to obtain intermediate C. Intermediate C and an inorganic base were reacted in solvent c by stirring, rotary evaporation, and purification to obtain the pyromellitic acid derivative.

2. The method for preparing the involute chiral polymer as described in claim 1, characterized in that, It must include at least one of the following (1) to (7): (1) The concentration of the pyromellitic amide derivative in the system is 0.05–2 mg / ml; (2) The solvent used to dissolve the trimesoamide derivative and trimesoylpyridinium amide includes one of acetonitrile, dioxane, acetone and N,N'-dimethylformamide; (3) The stirring time is 1 to 2 hours; (4) The molar ratio of the crosslinking agent to pyromellitic pyridylamine is (1-2.5):1; (5) The stirring reaction takes 2 to 7 days and the temperature is 25 to 30°C; (6) The washing conditions are washing with dioxane 2 to 3 times; (7) The drying temperature is 30-35℃.

3. The method for preparing the involute chiral polymer as described in claim 1, characterized in that, It must include at least one of the following (1) to (2): (1) In the preparation method of the pyromellitic acid, the molar ratio of pyromellitic acid to 3-aminomethylpyridine is 1:(2-3); (2) The stirring reaction time in the preparation method of the pyromellitic pyridylamine is 3 to 7 hours.

4. The method for preparing the involute chiral polymer as described in claim 1, characterized in that, It must include at least one of the following (1) to (8): (1) In step S1 of the preparation method of the trimesoamide derivative, the molar ratio of 4-(bromomethyl)benzylcarbamate tert-butyl ester and N-Boc-trans-4-hydroxy-D-proline methyl ester is 1:(1-2). (2) The catalyst in step S1 of the preparation method of the trimesoamide derivative is sodium hydride; (3) In step S1 of the preparation method of the pyromellitic tert-butyl ester, the molar ratio of the catalyst to tert-butyl 4-(bromomethyl)benzylcarbamate is (1-2):1; (4) In step S1 of the preparation method of the pyromellitic tricarboxamide derivative, the molar amount of trifluoroacetic acid is 700 eq of intermediate A, and the volume of solvent b is 3 times the volume of trifluoroacetic acid. (5) In step S2 of the preparation method of the pyromellitic tricarboxamide derivative, the molar ratio of the proline chiral catalytic unit and intermediate B is 1:(1-2); (6) The stirring reaction time in steps S1 and S2 of the preparation method of the pyromellitic tricarboxamide derivative is 3 to 7 hours; (7) The inorganic base in step S2 of the preparation method of the trimesoamide derivative is a sodium hydroxide aqueous solution with a concentration of 1 mol / L; (8) In step S2 of the preparation method of the trimesoamide derivative, the molar ratio of the inorganic base to the intermediate C is 5:

1.

5. The method for preparing the involute chiral polymer according to any one of claims 1 to 4, characterized in that, It must include at least one of the following (1) to (5): (1) The solvent a in the preparation method of the pyromellitic tricarboxamide derivative is N,N'-dimethylformamide; (2) The preparation method of the pyromellitic methyl methacrylate derivative includes N,N'-diisopropylethylamine and benzotriazole tetramethylurea hexafluorophosphate; (3) The solvent b in the preparation method of the pyromellitic tricarboxamide derivative is dichloromethane; (4) The solvent c in the preparation method of the pyromellitic tricarboxamide derivative is one of methanol and ethanol; (5) The purification method for the preparation of the trimesoamide derivative is column chromatography, wherein the packing material for the column chromatography is one of silica gel or neutral alumina, and the eluent is at least one of methanol, dichloromethane, ethyl acetate, and petroleum ether.

6. An involute chiral polymer prepared by the method described in any one of claims 1 to 5, characterized in that, The prepared involute chiral polymer has an inner cavity of 50–500 nm.

7. The application of the involute chiral polymer as described in claim 6 in the fields of selective catalytic Aldol reaction, chiral resolution, and selective adsorption.

8. The application as described in claim 7, characterized in that, The application of the involute chiral polymer in the selective catalytic Aldol reaction includes the following steps: The involute chiral polymer was dispersed in a mixed solvent of organic solvent and water, and trifluoroacetic acid. Alkyl ketones and substituted benzaldehydes were added, and the mixture was reacted at room temperature for 3-4 days to obtain the Aldol condensation product.

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