A catalyst for the synthesis of nervate from erucic acid, its preparation method and application

Abstract

This invention discloses a catalyst for the synthesis of nervate from erucic acid, its preparation method, and its applications, relating to the fields of organic synthesis and catalytic chemistry. The catalyst for the synthesis of nervate from erucic acid has the structure shown in formula (I). This invention provides a heterogeneous catalyst formed by the free radical polymerization of a cross-linked polymer containing vinylmethyl acridine onium salt and divinylbenzene. This catalyst can catalyze the reaction of erucic acid and acrylate to prepare nervate under blue LED irradiation, with a yield of nervate greater than 90%. The catalyst provided by this invention does not contain any metal elements and can achieve the green conversion of erucic acid to nervate with high efficiency and selectivity, and can be used for the efficient preparation of nervate and nervonic acid.

Description

Technical Field

[0001] This invention relates to the fields of organic synthesis and catalytic chemistry, and more specifically, to a catalyst for the synthesis of nervate from erucic acid, its preparation method, and its application. Background Technology

[0002] Nervonic acid (cis-15-tetracosenoic acid) and its esters are key precursors in the synthesis of sphingomyelin, a core component of nerve fibers and nerve cells. Studies have shown that nervonic acid has significant effects in repairing damaged nerve fibers, promoting nerve cell regeneration, and improving brain function. It has been widely used in the prevention and treatment of neurological diseases such as Alzheimer's disease, multiple sclerosis, and adrenoleukodystrophy, demonstrating significant pharmaceutical value and broad market prospects.

[0003] One of the classic synthetic routes for nervonic acid is through the decarboxylation coupling reaction of erucic acid (cis-13-docosaenoic acid) to achieve carbon chain elongation. The essence of this reaction is the coupling of two fatty acid molecules, followed by decarboxylation and esterification to generate nervonic acid esters. However, this reaction places high demands on the catalytic system; the catalyst performance directly affects the selectivity, yield, and extent of side reactions.

[0004] Currently, common methods for fatty acid decarboxylation coupling reactions include traditional electrolysis, transition metal catalysis, and photocatalysis. Traditional electrolysis typically requires high temperature and pressure conditions, resulting in high energy consumption, large equipment investment, and unsatisfactory selectivity for the target product. Transition metal catalysis often uses noble metal complexes such as palladium, nickel, and ruthenium as catalysts, but suffers from high catalyst costs, difficulty in removing metal residues, and harsh reaction conditions. In contrast, photocatalysis systems are attracting increasing attention due to their advantages of mild conditions, high controllability, and high selectivity.

[0005] Acridine onium salts are an important class of organic photo-redox catalysts, exhibiting unique advantages in photocatalytic organic conversion due to their excellent visible light absorption and strong oxidizing excited states. However, small-molecule acridine onium salt catalysts, acting as homogeneous catalysts in reactions, face the problem of difficulty in recycling. Polymerizing them to prepare polyacrylonitrile onium salt catalysts with well-defined structures, clearly defined active sites, and recyclability is an effective way to solve these problems.

[0006] Therefore, this invention provides a highly efficient, highly selective, mild-condition heterogeneous catalyst and its preparation method that does not require the use of precious metals, enabling the green conversion of erucic acid to nervonic acid esters. This has significant scientific and industrial application value in distinguishing between nervonic acid esters and nervonic acid esters. Summary of the Invention

[0007] To address the problems of high cost and difficulty in recycling catalysts used in the preparation of nervonic acid and nervonic acid esters in existing technologies, as well as the impact of metal residues on product purity and low catalytic efficiency, the present invention aims to provide a novel, efficient, and reusable organic heterogeneous catalyst and its preparation method for catalyzing the reaction of erucic acid or its ester derivatives to obtain nervonic acid esters in high yield and with high selectivity.

[0008] In view of this, the present invention provides a catalyst for the synthesis of nervate from erucic acid, a method for its preparation, and its application.

[0009] A catalyst for the synthesis of nervate from erucic acid, the catalyst having the structure shown in formula (I): Formula (I)

[0010] Among them, X - For Cl - ,Br - F - BF4 - PF6 - or TFSI - Any one of them; m, n, and r represent the degree of polymerization of the polymer.

[0011] m, n, and r represent the degree of polymerization of the polymer, which cannot be measured within a certain range.

[0012] The present invention also provides a method for preparing the catalyst for the synthesis of nervate from erucic acid, characterized by comprising the following steps: (1) Add an organic base to a suspension of methyltriphenylphosphine salt dissolved in diethyl ether and react at room temperature for 15-60 min. Then add acridine-9-carboxaldehyde to the system and react at room temperature for 8-24 h. After the reaction, wash with water, extract with dichloromethane, evaporate to dryness and purify by column chromatography to obtain intermediate product A. The molar ratio of acridine-9-carboxaldehyde, methyltriphenylphosphine salt and organic base is 1:(1-2):(1-2), and the mass ratio of diethyl ether and methyltriphenylphosphine salt is (10-20):1. (2) Add intermediate product A, divinylbenzene, initiator and toluene to the polymerization bottle. The system is subjected to three repeated freezing-vacuuming-thawing cycles to remove oxygen from the system. Then, the polymerization reaction is carried out at 60-80℃ for 50-100h. After the reaction, the product is diluted with tetrahydrofuran and precipitated with petroleum ether to obtain crude product. Then, the product is washed with hot ethanol 3-5 times to remove unpolymerized monomers. The product is dried under vacuum at 60-80℃ to obtain intermediate product B. The molar ratio of initiator, intermediate product A and divinylbenzene is 1:(100-2000):(40-400), and the mass ratio of intermediate product A to toluene is 1:(2-8). (3) Add methyl trifluoromethanesulfonate and acid-binding agent to the dispersion of intermediate product B dissolved in solvent dichloromethane, and then react at room temperature for 8-12 h. After the reaction, filter and wash with 3-5 times the amount of solvent dichloromethane, and then vacuum dry at 60-80℃ to obtain intermediate product C. The mass ratio of intermediate product B, methyl trifluoromethanesulfonate, acid-binding agent and solvent dichloromethane is 1:(4-8):(5-10):(8-15). (4) Disperse intermediate product C in solvent acetonitrile, then add metal salt, stir the reaction at 60-80℃ for 8-12h, filter after reaction and wash with 3-5 times the amount of solvent acetonitrile, and then vacuum dry at 60-80℃ to obtain the target catalyst, wherein the mass ratio of metal salt, intermediate product C and solvent acetonitrile is 1:(3-10):(20-100).

[0013] Furthermore, the methyltriphenylphosphine salt in step (1) is any one of methyltriphenylphosphine bromide, methyltriphenylphosphine chloride, or methyltriphenylphosphine iodide.

[0014] Furthermore, the organic base in step (1) is any one of potassium tert-butoxide, sodium tert-butoxide, sodium hydride, or n-butyllithium.

[0015] Further, the initiator in step (2) is any one of azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, dimethyl azobiscyclohexylcarboxylate phosphite, or 4,4'-azobis(4-cyanopentanoic acid).

[0016] Further, the acid-binding agent in step (3) is any one of 2,6-dimethylpyridine, 2,6-diethylpyridine, 2,6-dibutylpyridine or 2,6-ditert-butylpyridine.

[0017] Furthermore, the metal salt in step (4) is KX or NaX, wherein X - For Cl - , Br - F - BF4 - PF6 - TFSI - One of them.

[0018] The present invention also provides the application of the catalyst described above for the synthesis of nervate from erucic acid in the reaction of erucic acid with acrylate to prepare nervate.

[0019] Furthermore, the catalyst catalyzes the reaction of erucic acid and acrylate at 20-30°C for 6-12 hours under irradiation with a blue LED light source with a wavelength of 420-460nm to prepare nervate.

[0020] Furthermore, when the catalyst catalyzes the reaction of erucic acid and acrylate to prepare nervate, the molar ratio of erucic acid to acrylate is 1:1, and the acrylate is any one of methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, or tert-butyl acrylate.

[0021] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a heterogeneous catalyst formed by the free radical polymerization of a cross-linked polymer containing vinylmethyl acridine onium salt and divinylbenzene. This catalyst, under blue LED irradiation, can catalyze the reaction of erucic acid and acrylate to prepare nervate esters, with a yield of nervate esters greater than 90%. The catalyst provided by this invention does not contain any metal elements and can achieve the green conversion of erucic acid to nervate esters with high efficiency and selectivity, and can be used for the efficient preparation of nervate esters and nervonic acid. Attached Figure Description

[0022] Figure 1 The infrared absorption spectrum of the catalyst prepared in Example 1 is shown.

[0023] Figure 2 This invention provides a catalyst synthesis route for the synthesis of nervate from erucic acid. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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 skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0025] (1) Potassium tert-butoxide (1.35 g, 0.012 mol, 1.2 eq) was added to a suspension of methyltriphenylphosphine bromide (4.29 g, 0.01 mol, 1.0 eq) dissolved in anhydrous diethyl ether (61 mL), and the mixture was reacted at room temperature for 30 min. Then, acridine-9-carboxaldehyde (2.07 g, 0.01 mol, 1 eq) was added to the system, and the mixture was reacted at room temperature for 16 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (70 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 8:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0026] (2) Add intermediate product A (0.50 g, 1.43 mmol, 125.0 eq), divinylbenzene (0.28 g, 1.72 mmol, 150.0 eq), initiator azobisisobutyronitrile (0.0019 g, 0.0114 mmol, 1 eq), and toluene (2.9 mL, 625.0 eq) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw until completely thawed, repeat the above operation three times. Place the polymerization flask in a 70℃ oil bath for polymerization for 72 h. After the reaction is complete, add tetrahydrofuran (10 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (15 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 70℃ for 24 h to obtain intermediate product B.

[0027] (3) Methyl trifluoromethanesulfonate (2.75 g) and acid-binding agent 2,6-dimethylpyridine (3.25 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.5 mL), and the mixture was reacted at room temperature for 10 h. After the reaction, the mixture was filtered, and the solid was washed with 4 times its volume of dichloromethane. The solid was dried under vacuum at 70 °C for 12 h to obtain intermediate product C.

[0028] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (25 mL) solvent, and then potassium chloride (0.075 g) was added. The mixture was stirred at 70 °C for 10 h. After the reaction, the mixture was filtered, and the solid was washed four times with acetonitrile (15 mL) solvent. The solid was dried under vacuum at 70 °C for 12 h to obtain the target catalyst.

[0029] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), methyl acrylate (86.1 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source with a wavelength of 450 nm and stirred at 25 °C for 8 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain methyl nervonic acid in 93.8% yield. Example 2

[0030] (1) Sodium tert-butoxide (1.15 g, 0.012 mol, 1.2 eq) was added to a suspension of methyltriphenylphosphine chloride (3.74 g, 0.01 mol, 1.0 eq) dissolved in anhydrous diethyl ether (61 mL), and the mixture was reacted at room temperature for 40 min. Then, acridine-9-carboxaldehyde (2.07 g, 0.01 mol, 1 eq) was added to the system, and the mixture was reacted at room temperature for 18 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (70 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 7:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0031] (2) Add intermediate product A (0.50 g, 1.43 mmol, 229 eq), divinylbenzene (0.24 g, 1.43 mmol, 229 eq), initiator azobisisobutyronitrile (0.00155 g, 0.00625 mmol, 1 eq), and toluene (3.5 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in a 75℃ oil bath for polymerization for 80 h. After the reaction is complete, add tetrahydrofuran (12 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (15 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 75℃ for 24 h to obtain intermediate product B.

[0032] (3) Methyl trifluoromethanesulfonate (2.50 g) and acid-binding agent 2,6-diethylpyridine (3.50 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.0 mL), and the mixture was reacted at room temperature for 11 h. After the reaction, the mixture was filtered, and the solid was washed three times with dichloromethane (5.0 mL). The solid was dried under vacuum at 75 °C for 12 h to obtain intermediate product C.

[0033] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (22 mL) solvent, and then sodium bromide (0.10 g) was added. The mixture was stirred at 75 °C for 9 h. After the reaction, the mixture was filtered, and the solid was washed three times with acetonitrile (12 mL). The solid was dried under vacuum at 75 °C for 12 h to obtain the target catalyst.

[0034] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), ethyl acrylate (100.1 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source with a wavelength of 440 nm and stirred at 28 °C for 6 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain ethyl nervate in 92.2% yield. Example 3

[0035] (1) Sodium hydride (0.24 g, 0.006 mol, 1.2 eq) was added to a suspension of methyltriphenylphosphine iodide (2.59 g, 0.005 mol, 1.0 eq) dissolved in anhydrous diethyl ether (37 mL), and reacted at room temperature for 35 min. Then, acridine-9-carboxaldehyde (1.04 g, 0.005 mol, 1 eq) was added to the system, and the reaction was carried out at room temperature for 20 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (40 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 9:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0036] (2) Add intermediate product A (0.50 g, 1.43 mmol, 253 eq), divinylbenzene (0.33 g, 2.00 mmol, 354 eq), initiator dimethyl azobisisobutyrate (0.0013 g, 0.00565 mmol, 1 eq), and toluene (2.5 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in a 65℃ oil bath for polymerization for 95 h. After the reaction is complete, add tetrahydrofuran (11 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (18 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 65℃ for 24 h to obtain intermediate product B.

[0037] (3) Methyl trifluoromethanesulfonate (3.00 g) and acid-binding agent 2,6-dibutylpyridine (4.00 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.5 mL), and the mixture was reacted at room temperature for 9 h. After the reaction, the mixture was filtered, and the solid was washed four times with dichloromethane (5.5 mL). The solid was dried under vacuum at 65 °C for 12 h to obtain intermediate product C.

[0038] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (30 mL) solvent, and then potassium fluoride (0.06 g) was added. The mixture was stirred at 65 °C for 11 h. After the reaction, the mixture was filtered, and the solid was washed four times with acetonitrile (12 mL). The solid was dried under vacuum at 65 °C for 12 h to obtain the target catalyst.

[0039] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), propyl acrylate (114.1 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under blue LED light at a wavelength of 460 nm and stirred at 22 °C for 10 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain propyl nervonic acid in 91.4% yield. Example 4

[0040] (1) To a suspension of methyltriphenyltetrafluoroborate phosphine (4.40 g, 0.01 mol, 1.0 eq) dissolved in anhydrous diethyl ether (62 mL), n-butyllithium (4.0 mL, 0.01 mol, 1.0 eq) was added and reacted at room temperature for 25 min. Then, acridine-9-carboxaldehyde (2.07 g, 0.01 mol, 1.0 eq) was added and reacted at room temperature for 12 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (70 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 6:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0041] (2) Add intermediate product A (0.50 g, 1.43 mmol, 297 eq), divinylbenzene (0.27 g, 1.66 mmol, 345 eq), initiator 4,4'-azobis(4-cyanopentanoic acid) (0.00135 g, 0.00482 mmol, 1 eq), and toluene (4.6 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: immerse the polymerization flask in liquid nitrogen to freeze until the material is completely solidified, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw until completely thawed. Repeat the above operation three times. Place the polymerization flask in a 70°C oil bath for polymerization for 70 h. After the reaction is complete, add tetrahydrofuran (14 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product. Wash three times with hot ethanol (15 mL) to remove unpolymerized monomers. Finally, the product was dried under vacuum at 70°C for 24 h to obtain intermediate product B.

[0042] (3) Methyl trifluoromethanesulfonate (2.25 g) and acid-binding agent 2,6-di-tert-butylpyridine (3.00 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (4.0 mL), and the mixture was reacted at room temperature for 12 h. After the reaction, the mixture was filtered, and the solid was washed three times with dichloromethane (4.0 mL). The solid was dried under vacuum at 70 °C for 12 h to obtain intermediate product C.

[0043] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (15 mL) solvent, and then sodium tetrafluoroborate (0.165 g) was added. The mixture was stirred at 70 °C for 8 h. After the reaction, the mixture was filtered, and the solid was washed three times with acetonitrile (10 mL). The solid was dried under vacuum at 70 °C for 12 h to obtain the target catalyst.

[0044] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), isopropyl acrylate (114.1 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source at a wavelength of 430 nm and stirred at 25 °C for 12 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain nervonic acid isopropyl acrylate in 90.9% yield. Example 5

[0045] (1) Potassium tert-butoxide (0.67 g, 0.006 mol, 1.2 eq) was added to a suspension of methyltriphenylhexafluorophosphate (2.50 g, 0.005 mol, 1.0 eq) dissolved in anhydrous diethyl ether (36 mL), and the mixture was reacted at room temperature for 50 min. Then, acridine-9-carboxaldehyde (1.04 g, 0.005 mol, 1.0 eq) was added to the system, and the mixture was reacted at room temperature for 24 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (40 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 10:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0046] (2) Add intermediate product A (0.50 g, 1.43 mmol, 120 eq), divinylbenzene (0.28 g, 1.72 mmol, 144 eq), initiator azobisisobutyronitrile (0.00195 g, 0.0119 mmol, 1 eq), and toluene (4.0 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in a 75℃ oil bath for polymerization for 85 h. After the reaction is complete, add tetrahydrofuran (12 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (15 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 75℃ for 24 h to obtain intermediate product B.

[0047] (3) Methyl trifluoromethanesulfonate (3.50 g) and acid-binding agent 2,6-dimethylpyridine (4.50 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.5 mL), and the mixture was reacted at room temperature for 8 h. After the reaction, the mixture was filtered, and the solid was washed 5 times with dichloromethane (5.5 mL). The solid was dried under vacuum at 75 °C for 12 h to obtain intermediate product C.

[0048] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (40 mL) solvent, and then potassium hexafluorophosphate (0.07 g) was added. The mixture was stirred at 65 °C for 12 h. After the reaction, the mixture was filtered, and the solid was washed four times with acetonitrile (18 mL). The solid was dried under vacuum at 65 °C for 12 h to obtain the target catalyst.

[0049] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), butyl acrylate (128.2 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source with a wavelength of 450 nm and stirred at 30 °C for 7 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain butyl nervate in 93.2% yield. Example 6

[0050] (1) Sodium tert-butoxide (0.29 g, 0.003 mol, 1.5 eq) was added to a suspension of methyltriphenylbis(trifluoromethanesulfonyl)imide phosphine (1.32 g, 0.002 mol, 1.0 eq) dissolved in anhydrous diethyl ether (19 mL), and reacted at room temperature for 45 min. Then, acridine-9-carboxaldehyde (0.41 g, 0.002 mol, 1.0 eq) was added to the system, and the reaction was carried out at room temperature for 15 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (20 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 5:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0051] (2) Add intermediate product A (0.50 g, 1.43 mmol, 322 eq), divinylbenzene (0.19 g, 1.14 mmol, 257 eq), initiator azobisisobutyronitrile (0.0011 g, 0.00444 mmol, 1 eq), and toluene (1.7 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in an oil bath at 80 °C for 60 h for polymerization. After the reaction is complete, add tetrahydrofuran (15 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash five times with hot ethanol (12 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 80 °C for 24 h to obtain intermediate product B.

[0052] (3) Methyl trifluoromethanesulfonate (3.25 g) and acid-binding agent 2,6-diethylpyridine (4.25 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.0 mL), and the mixture was reacted at room temperature for 10 h. After the reaction, the mixture was filtered, and the solid was washed four times with dichloromethane (5.0 mL). The solid was dried under vacuum at 80 °C for 12 h to obtain intermediate product C.

[0053] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (35 mL) solvent, and then sodium bis(trifluoromethanesulfonyl)imide (0.09 g) was added. The mixture was stirred at 70 °C for 10 h. After the reaction, the mixture was filtered, and the solid was washed three times with acetonitrile (15 mL). The solid was dried under vacuum at 70 °C for 12 h to obtain the target catalyst.

[0054] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), isobutyl acrylate (128.2 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source at a wavelength of 420 nm and stirred at 20 °C for 12 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain nervonic acid isobutyl ester in 90.2% yield. Example 7

[0055] (1) Sodium hydride (0.24 g, 0.006 mol, 1.2 eq) was added to a suspension of methyltriphenylphosphine bromide (2.15 g, 0.005 mol, 1.0 eq) dissolved in anhydrous diethyl ether (33 mL), and reacted at room temperature for 20 min. Then, acridine-9-carboxaldehyde (1.04 g, 0.005 mol, 1.0 eq) was added to the system, and the reaction was carried out at room temperature for 22 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (40 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 8:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0056] (2) Add intermediate product A (0.50 g, 1.43 mmol, 253 eq), divinylbenzene (0.33 g, 2.00 mmol, 354 eq), initiator dimethyl azobisisobutyrate (0.0013 g, 0.00565 mmol, 1 eq), and toluene (3.2 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in a 75℃ oil bath for polymerization for 75 h. After the reaction is complete, add tetrahydrofuran (10 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (18 mL) to remove unpolymerized monomers. Finally, vacuum dry at 75℃ for 24 h to obtain intermediate product B.

[0057] (3) Methyl trifluoromethanesulfonate (2.90 g) and acid-binding agent 2,6-dibutylpyridine (3.60 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (4.5 mL), and the mixture was reacted at room temperature for 10.5 h. After the reaction, the mixture was filtered, and the solid was washed three times with dichloromethane (4.5 mL). The solid was dried under vacuum at 75 °C for 12 h to obtain intermediate product C.

[0058] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (28 mL) solvent, and then potassium bromide (0.11 g) was added. The mixture was stirred at 70 °C for 9 h. After the reaction, the mixture was filtered, and the solid was washed four times with acetonitrile (12 mL). The solid was dried under vacuum at 70 °C for 12 h to obtain the target catalyst.

[0059] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), tert-butyl acrylate (128.2 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source with a wavelength of 450 nm and stirred at 25 °C for 9 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain tert-butyl nervate in 91.6% yield. Example 8

[0060] (1) To a suspension of methyltriphenylphosphine chloride (0.75 g, 0.002 mol, 1.0 eq) dissolved in anhydrous diethyl ether (14 mL), n-butyllithium (0.96 mL, 0.0024 mol, 1.2 eq) was added and reacted at room temperature for 15 min. Then, acridine-9-carboxaldehyde (0.41 g, 0.002 mol, 1.0 eq) was added and reacted at room temperature for 10 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (20 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 7:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0061] (2) Add intermediate product A (0.50 g, 1.43 mmol, 320 eq), divinylbenzene (0.24 g, 1.43 mmol, 320 eq), initiator 4,4'-azobis(4-cyanopentanoic acid) (0.00125 g, 0.00446 mmol, 1 eq), and toluene (2.3 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw until completely thawed, repeat the above operation three times. Place the polymerization flask in a 70℃ oil bath for polymerization for 90 h. After the reaction is complete, add tetrahydrofuran (12 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, and wash it four times with hot ethanol (15 mL) to remove unpolymerized monomers. Finally, the product was dried under vacuum at 70°C for 24 h to obtain intermediate product B.

[0062] (3) Methyl trifluoromethanesulfonate (3.75 g) and acid-binding agent 2,6-di-tert-butylpyridine (5.00 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.0 mL), and the mixture was reacted at room temperature for 8 h. After the reaction, the mixture was filtered, and the solid was washed 5 times with dichloromethane (5.0 mL). The solid was dried under vacuum at 70 °C for 12 h to obtain intermediate product C.

[0063] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (20 mL) solvent, and then sodium chloride (0.06 g) was added. The mixture was stirred at 80 °C for 8 h. After the reaction, the mixture was filtered, and the solid was washed 33 times with acetonitrile (10 mL). The solid was dried under vacuum at 80 °C for 12 h to obtain the target catalyst.

[0064] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), methyl acrylate (86.1 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source at a wavelength of 445 nm and stirred at 26 °C for 10 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain methyl nervate in 91.7% yield. Example 9

[0065] (1) Potassium tert-butoxide (1.35 g, 0.012 mol, 1.2 eq) was added to a suspension of methyltriphenylphosphine iodide (5.18 g, 0.01 mol, 1.0 eq) dissolved in anhydrous diethyl ether (73 mL), and the mixture was reacted at room temperature for 55 min. Then, acridine-9-carboxaldehyde (2.07 g, 0.01 mol, 1.0 eq) was added to the system, and the mixture was reacted at room temperature for 14 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (70 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 6:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0066] (2) Add intermediate product A (0.50 g, 1.43 mmol, 127 eq), divinylbenzene (0.42 g, 2.58 mmol, 228 eq), initiator azobisisobutyronitrile (0.00185 g, 0.0113 mmol, 1 eq), and toluene (4.6 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in a 65℃ oil bath for polymerization for 100 h. After the reaction is complete, add tetrahydrofuran (17 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (20 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 65℃ for 24 h to obtain intermediate product B.

[0067] (3) Methyl trifluoromethanesulfonate (3.00 g) and acid-binding agent 2,6-dimethylpyridine (3.50 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.5 mL), and the mixture was reacted at room temperature for 11 h. After the reaction, the mixture was filtered, and the solid was washed four times with dichloromethane (5.5 mL). The solid was dried under vacuum at 65 °C for 12 h to obtain intermediate product C.

[0068] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (45 mL) solvent, and then potassium hexafluorophosphate (0.08 g) was added. The mixture was stirred at 60 °C for 12 h. After the reaction, the mixture was filtered, and the solid was washed 5 times with acetonitrile (18 mL). The solid was dried under vacuum at 60 °C for 12 h to obtain the target catalyst.

[0069] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), ethyl acrylate (100.1 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source at a wavelength of 460 nm and stirred at 23 °C for 11 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain ethyl nervate in 90.5% yield. Example 10

[0070] (1) Sodium tert-butoxide (0.58 g, 0.006 mol, 1.2 eq) was added to a suspension of methyltriphenyltetrafluoroborate (2.20 g, 0.005 mol, 1.0 eq) dissolved in anhydrous diethyl ether (35 mL), and the mixture was reacted at room temperature for 60 min. Then, acridine-9-carboxaldehyde (1.04 g, 0.005 mol, 1.0 eq) was added to the system, and the mixture was reacted at room temperature for 24 h. After the reaction, the mixture was transferred to a separatory funnel and washed three times with deionized water (40 mL). The aqueous phase was extracted with dichloromethane, and the organic phases were combined and dried with anhydrous sodium sulfate for 30 min. After filtration, the solvent was removed by rotary evaporation under reduced pressure at 40 °C. The crude product was purified by column chromatography (silica gel 200-300 mesh, eluent: petroleum ether: ethyl acetate = 8:1, volume ratio), and the target fraction was collected and evaporated to dryness to obtain intermediate product A.

[0071] (2) Add intermediate product A (0.50 g, 1.43 mmol, 284 eq), divinylbenzene (0.19 g, 1.14 mmol, 226 eq), initiator azobisisobutyronitrile (0.00125 g, 0.00504 mmol, 1 eq), and toluene (1.5 mL) to the polymerization flask. Seal the polymerization flask and remove oxygen from the system by repeating the freeze-vacuum-thaw cycle three times: seal the polymerization flask, open the vacuum valve to evacuate to a pressure <0.1 mbar and maintain for 5 min, close the valve and place it in a room temperature water bath to thaw completely, repeat the above operation three times. Place the polymerization flask in an oil bath at 80 °C for 55 h for polymerization. After the reaction is complete, add tetrahydrofuran (10 mL) to dilute the reaction solution, then slowly add petroleum ether to precipitate and filter to collect the crude product, wash three times with hot ethanol (12 mL) to remove unpolymerized monomers. Finally, dry under vacuum at 80 °C for 24 h to obtain intermediate product B.

[0072] (3) Methyl trifluoromethanesulfonate (2.50 g) and acid-binding agent 2,6-diethylpyridine (3.75 g) were added to a dispersion of intermediate product B (0.50 g) dissolved in dichloromethane (5.5 mL), and the mixture was reacted at room temperature for 9.5 h. After the reaction, the mixture was filtered, and the solid was washed three times with dichloromethane (5.5 mL). The solid was dried under vacuum at 80 °C for 12 h to obtain intermediate product C.

[0073] (4) The intermediate product C (0.50 g) was dispersed in acetonitrile (25 mL) solvent, and then sodium tetrafluoroborate (0.10 g) was added. The mixture was stirred at 75 °C for 10 h. After the reaction, the mixture was filtered, and the solid was washed four times with acetonitrile (12 mL). The solid was dried under vacuum at 75 °C for 12 h to obtain the target catalyst.

[0074] The target catalyst (5.0 mg) was added to a reaction tube, followed by erucic acid (338.6 mg, 1.0 mmol, 1 eq), butyl acrylate (128.2 mg, 1.0 mmol, 1 eq), and toluene (2 mL). The reaction tube was placed under a blue LED light source with a wavelength of 450 nm and stirred at 28 °C for 8 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain butyl nervate in 92.1% yield.

[0075] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A catalyst for the synthesis of nervate from erucic acid, characterized in that, The catalyst has the structure shown in formula (I): Equation (I) Among them, X - For Cl - ,Br - F - BF4 - PF6 - or TFSI - Any one of them; m, n, and r represent the degree of polymerization of the polymer.

2. A method for preparing the catalyst for the synthesis of nervate from erucic acid as described in claim 1, characterized in that, Includes the following steps: An organic base was added to a suspension of methyltriphenylphosphine salt dissolved in diethyl ether, and the mixture was reacted at room temperature for 15-60 min. Then, acridine-9-carboxaldehyde was added to the system and the mixture was reacted at room temperature for 8-24 h. After the reaction, the mixture was washed with water, extracted with dichloromethane, dried by rotary evaporation, and purified by column chromatography to obtain intermediate product A. The molar ratio of acridine-9-carboxaldehyde, methyltriphenylphosphine salt, and organic base was 1:(1-2):(1-2), and the mass ratio of diethyl ether to methyltriphenylphosphine salt was (10-20):

1. Intermediate product A, divinylbenzene, initiator and toluene were added to a polymerization flask. The system was subjected to three repeated freeze-vacuum-thaw cycles to remove oxygen. The polymerization reaction was then carried out at 60-80℃ for 50-100h. After the reaction, the product was diluted with tetrahydrofuran and precipitated with petroleum ether to obtain a crude product. The crude product was then washed with hot ethanol 3-5 times to remove unpolymerized monomers. The product was then vacuum dried at 60-80℃ to obtain intermediate product B. The molar ratio of initiator, intermediate product A and divinylbenzene was 1:(100-2000):(40-400), and the mass ratio of intermediate product A to toluene was 1:(2-8). Methyl trifluoromethanesulfonate and an acid-binding agent were added to a dispersion of intermediate product B dissolved in dichloromethane. The mixture was then reacted at room temperature for 8-12 hours. After the reaction, the mixture was filtered and washed with 3-5 times the amount of dichloromethane. The mixture was then dried under vacuum at 60-80°C to obtain intermediate product C. The mass ratio of intermediate product B, methyl trifluoromethanesulfonate, acid-binding agent and dichloromethane was 1:(4-8):(5-10):(8-15). Intermediate product C was dispersed in solvent acetonitrile, and then metal salt was added. The mixture was stirred at 60-80℃ for 8-12 hours. After the reaction, the mixture was filtered and washed with 3-5 times the amount of solvent acetonitrile. The mixture was then vacuum dried at 60-80℃ to obtain the target catalyst. The mass ratio of metal salt, intermediate product C and solvent acetonitrile was 1:(3-10):(20-100).

3. The method for preparing the catalyst for the synthesis of nervate from erucic acid according to claim 2, characterized in that, The methyltriphenylphosphine salt mentioned in step (1) is any one of methyltriphenylphosphine bromide, methyltriphenylphosphine chloride, or methyltriphenylphosphine iodide.

4. The method for preparing the catalyst for the synthesis of nervate from erucic acid according to claim 2, characterized in that, The organic base in step (1) is any one of potassium tert-butoxide, sodium tert-butoxide, sodium hydride, or n-butyllithium.

5. The method for preparing the catalyst for the synthesis of nervate from erucic acid according to claim 2, characterized in that, The initiator in step (2) is any one of azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, dimethyl azobiscyclohexylcarboxylate phosphite, or 4,4'-azobis(4-cyanopentanoic acid).

6. The method for preparing the catalyst for the synthesis of nervate from erucic acid according to claim 2, characterized in that, The acid-binding agent in step (3) is any one of 2,6-dimethylpyridine, 2,6-diethylpyridine, 2,6-dibutylpyridine or 2,6-ditert-butylpyridine.

7. The method for preparing the catalyst for the synthesis of nervate from erucic acid according to claim 2, characterized in that, The metal salt mentioned in step (4) is KX or NaX, wherein X - For Cl - , Br - F - BF4 - PF6 - TFSI - One of them.

8. The use of the catalyst of claim 1 for the synthesis of nervate from erucic acid in the reaction of erucic acid with acrylate to prepare nervate.

9. The application of the catalyst for the synthesis of nervate from erucic acid according to claim 8 in the reaction of erucic acid with acrylate to prepare nervate, characterized in that, The catalyst catalyzes the reaction of erucic acid and acrylate at 20-30°C for 6-12 hours under irradiation with a blue LED light source with a wavelength of 420-460nm to prepare nervate.

10. The application of the catalyst for the synthesis of nervate from erucic acid according to claim 8 in the reaction of erucic acid with acrylate to prepare nervate, characterized in that, The catalyst catalyzes the reaction of erucic acid and acrylate to prepare nervate in a molar ratio of 1:1, wherein the acrylate is any one of methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, or tert-butyl acrylate.

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