Preparation method of burkeric acid, cycloolefin copolymerization catalyst prepared from burkeric acid as well as preparation method and application of cycloolefin copolymerization catalyst

Abstract

The invention provides a preparation method of burkritic acid, a cycloolefin copolymerization catalyst prepared from burkritic acid and a preparation method and application of the cycloolefin copolymerization catalyst, and the preparation method comprises the following steps: in the presence of a nitrogen heteroatom carbene ligand, reacting a compound 1j with a compound 2 to obtain a compound 3; and hydrolyzing the compound 3 under the action of tributyltin oxide to obtain the (-)-burclalic acid. According to the synthetic route provided by the invention, by taking nitrogen heteroatom carbene as a catalyst, racemic ester is subjected to kinetic resolution, enantiomer selective ester exchange is realized, and a chiral alcohol iodization step and a chiral acyl chloride preparation step reported in literatures are simplified, so that the synthesis of the burclalic acid is simpler and more efficient, the synthesis cost is reduced, and the yield is increased. And the cost of synthesizing the ROMP catalyst is reduced. The catalyst for preparing the cycloolefin copolymer can be compounded with a cocatalyst to be used for synthesizing the cycloolefin copolymer, has higher catalytic activity and is insensitive to water and oxygen.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, and relates to a method for preparing bercrolic acid, a cycloolefin copolymerization catalyst prepared from bercrolic acid, its preparation method and application. Background Technology

[0002] Currently, the mainstream ring-opening heteropolymerization (ROMP) catalysts for COC (cyclic olefin copolymers) mainly include transition metal salts such as tungsten, molybdenum, and rhodium, and Grubbs-type catalysts. However, these catalysts have excessively high reactivity and rapid reaction rates, making temperature control difficult, and they are sensitive to water and oxygen. While Grubbs catalysts are insensitive to water and oxygen, their reactivity is relatively low. Utilizing polycyclic epoxy compounds with multi-chiral centers to form complex catalysts with highly reactive transition metal salts can effectively control reactivity while reducing the reaction rate between the catalyst and water and oxygen. (-)-Burklionic acid has a strong coordination effect with transition metals, forming stable complexes. These complexes exhibit high ROMP activity and are insensitive to water and oxygen. However, the current synthetic route for (-)-Burklionic acid is lengthy and has low yields, resulting in high costs for synthesizing ROMP catalysts.

[0003] (-)-Berkley acid, chemical structure: C24H29O9, specific structural formula is as follows: This compound has six chiral centers and three connected epoxy rings, thus exhibiting strong coordination ability and forming stable complexes. However, current synthetic routes for this compound are complex, yielding low amounts and presenting difficulties in separation.

[0004] The most concise synthetic method currently reported is that of (Qianghui Zhou, et al., A Concise Total Synthesis of (–)-Berkelic Acid, Angew. Chem. Int. Ed. 2021, 60, 5141), which achieves the total synthesis of (–)-Berkelic Acid through a three-component Catellani / oxa-Michael addition tandem reaction, a one-pot deprotection / acid-catalyzed spiroketalization, and a nickel-catalyzed reductive coupling reaction. However, the reported yield is still relatively low, and the steps are not concise enough, resulting in a long synthetic route, low yield, and high cost.

[0005] Therefore, there is a need in this field to obtain a simpler route for the synthesis of bercrolic acid in order to reduce the cost of synthesizing ROMP catalysts. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a method for preparing bercrolic acid, as well as a cyclic olefin copolymerization catalyst prepared from bercrolic acid, its preparation method, and its applications. The synthetic route provided by this invention utilizes nitrogen-heteroatom carbene as a catalyst to achieve kinetic resolution of racemic esters, realizing enantioselective transesterification. This simplifies the chiral alcohol iodination and chiral acyl chloride preparation steps reported in the literature, making the synthesis of bercrolic acid simpler and more efficient, reducing synthesis costs, and lowering the cost of synthesizing ROMP catalysts.

[0007] To achieve this objective, the present invention employs the following technical solution:

[0008] On one hand, the present invention provides a method for preparing (-)-berkelic acid, the method comprising the following steps:

[0009] (1) In the presence of a nitrogen-atom carbene ligand, compound 1j reacts with compound 2 to give compound 3, as shown in the following reaction equation:

[0010]

[0011] (2) Compound 3 is hydrolyzed in the presence of a hydrolysis catalyst to give (-)-Berkley acid, as shown in the following reaction formula:

[0012]

[0013] The preparation method of the present invention uses nitrogen heteroatom carbene as a catalyst, which can directly react compound 1j and racemic compound 2 to obtain compound 3 directly, without converting compound 1j into a halide, or converting racemic compound 2 into an acyl chloride compound beforehand, and without resolving it into a chiral acyl chloride compound. Therefore, the reaction synthesis of the present invention is simpler and more efficient, simplifies the reaction steps, reduces the synthesis cost, and reduces the cost of synthesizing ROMP catalyst.

[0014] Preferably, the nitrogen-heteroatom carbene ligand comprises any one or a combination of at least two of the following ligands:

[0015]

[0016] Preferably, the molar ratio of compound 1j and compound 2 in step (1) is 1:1 to 1:5, for example, 1:1, 1:1.5, 1:1.8, 1:2, 1:2.5, 1:2.8, 1:3, 1:3.5, 1:3.8, 1:4, 1:4.5, 1:4.8 or 1:5.

[0017] Preferably, the molar ratio of the nitrogen heteroatom carbene ligand to compound 2 in step (1) is 0.1:1-0.5:1, for example 0.1:1, 0.2:1, 0.3:1, 0.4:1 or 0.5:1.

[0018] Preferably, the reaction in step (1) is carried out in the presence of arylboronic acid.

[0019] Preferably, the arylboronic acid comprises any one or a combination of at least two of the following: phenylboronic acid, 4-chlorophenylboronic acid, 4-fluorophenylboronic acid, 4-methoxyboronic acid, 4-carboxyphenylboronic acid, 1-naphthoboronic acid, 4-bromophenylboronic acid, 3-carboxyphenylboronic acid, 2-naphthoboronic acid, 4-trifluoromethylphenylboronic acid, 3-fluorophenylboronic acid, 4-tolueneboronic acid, 3-chlorophenylboronic acid, 3,5-dichlorophenylboronic acid, 3-methoxyphenylboronic acid, 4-cyanophenylboronic acid, 4-formylphenylboronic acid, 2,4-dichlorophenylboronic acid, 3,4,5-trifluorophenylboronic acid, 4-trifluoromethoxyphenylboronic acid, 2-methylphenylboronic acid, or 4-biphenylboronic acid.

[0020] Preferably, the molar ratio of the arylboronic acid to compound 2 is 1:1 to 1:5, for example, 1:1, 1:1.5, 1:1.8, 1:2, 1:2.5, 1:2.8, 1:3, 1:3.5, 1:3.8, 1:4, 1:4.5, 1:4.8 or 1:5.

[0021] Preferably, the reaction in step (1) is carried out in the presence of a dehydrogenating agent.

[0022] Preferably, the dehydrogenating agent includes any one of sodium hydride, calcium hydride, n-butyllithium, tert-butyllithium, sodium ethoxide, sodium hydroxide, and diisopropylaminolithium.

[0023] Preferably, the molar ratio of the dehydrogenating agent to compound 2 is 0.01:1 to 1:1, for example, 0.01:1, 0.03:1, 0.05:1, 0.08:1, 0.1:1, 0.3:1, 0.5:1, 0.8:1 or 1:1.

[0024] Preferably, the reaction in step (1) is carried out in... The process is carried out in the presence of molecular sieves.

[0025] Preferably, relative to 1 mol of compound 2, the The amount of molecular sieve used is 100g-5000g, for example, 100g, 200g, 300g, 500g, 700g, 900g, 1000g, 1500g, 2000g, 2500g, 3000g, 3500g, 4000g, 4500g or 5000g.

[0026] Preferably, the reaction in step (1) is carried out in a solvent selected from any one or a combination of at least two of the following: water, formamide, acetonitrile, methanol, ethanol, propanol, acetone, dioxane, tetrahydrofuran, methyl ethyl ketone, n-butanol, ethyl acetate, diethyl ether, isopropyl ether, dichloromethane, chloroform, bromoethane, benzene, carbon tetrachloride, carbon disulfide, cyclohexane, or n-hexane.

[0027] Preferably, the reaction temperature in step (1) is 0℃-100℃, for example 0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃ or 100℃, and the reaction time is 6h-12h, for example 6h, 8h, 10h or 12h.

[0028] Preferably, the molar ratio of the hydrolysis catalyst to compound 3 in step (2) is 1:1-30.

[0029] Preferably, the reaction in step (2) is carried out in a solvent selected from one or a combination of at least two of tetrahydrofuran, n-hexane, cyclohexane, ethyl acetate or toluene.

[0030] Preferably, the reaction temperature in step (2) is 80℃-150℃, for example 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃ or 150℃, and the reaction time is 3-10h, for example 3h, 4h, 5h, 6h, 7h, 8h, 9h or 10h.

[0031] In this invention, the raw material compound 1j used in step (1) can be purchased or synthesized according to a publicly available synthetic route.

[0032] Secondly, the present invention provides bercrolic acid prepared by the preparation method described above.

[0033] Thirdly, the present invention provides a catalyst for preparing cyclic olefin copolymers, the catalyst having the structure described in formula (1):

[0034]

[0035] Where R1 and R2 independently represent hydrogen atom, halogen atom, cyano group, and C2-C group. 10 Alkyl groups; C1-C 10 The alkoxy group, substituted or unsubstituted C6-C20 aryloxy group, wherein R1 and R2 exist independently or are connected to each other to form a cyclic structure; M is one of palladium, nickel, rhodium or tungsten.

[0036] In this invention, the halogen atom is fluorine, chlorine, or bromine.

[0037] Preferably, the C1-C 10 The alkoxy group is selected from methoxy, ethoxy, isopropoxy, etc.; the aryloxy group is selected from phenoxy, p-tolyloxy, m-tolyloxy, etc.

[0038] Fourthly, the present invention provides a method for preparing a catalyst for preparing cyclic olefin copolymers as described above, the method comprising the following steps:

[0039] The catalyst for preparing cyclic olefin copolymers is obtained by reacting (-)-Berkliic acid with a metal chloride.

[0040] Preferably, the molar ratio of (-)-berklic acid to metal chloride is 1:1 to 1:10, for example, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10.

[0041] Preferably, the reaction is carried out in an organic solvent selected from at least one of cyclohexane, n-hexane, or toluene.

[0042] In this invention, the reaction is carried out in an anhydrous and oxygen-free environment.

[0043] Preferably, the reaction is carried out under nitrogen protection.

[0044] Preferably, the metal chloride is added dropwise to the reaction system containing (-)-Berklionic acid, and the dropwise addition is carried out at -10°C to 10°C (e.g., -10°C, -5°C, 0°C, 5°C or 10°C).

[0045] Preferably, after the addition is complete, the reaction is carried out at room temperature (15-30°C, for example, 15°C, 20°C, 25°C or 30°C); the reaction time is 10 minutes to 60 minutes.

[0046] Preferably, the catalyst for preparing cyclic olefin copolymers is obtained by vacuum distillation after the reaction is completed.

[0047] Preferably, the reduced pressure distillation pressure is -0.4 bar to -1 bar (e.g., -0.4 bar, -0.6 bar, -0.8 bar or -1 bar), and the temperature is 25°C to 50°C (e.g., 25°C, 28°C, 30°C, 35°C, 38°C, 40°C, 45°C, 48°C or 50°C).

[0048] Fifthly, the present invention provides a composite catalyst comprising a main catalyst and a co-catalyst, wherein the main catalyst is the catalyst described in the third aspect, and the co-catalyst comprises one or a combination of at least two of aluminum chloride (AlCl3), aluminum trifluoromethanesulfonate (Al(OTf)3), trimethylaluminum (AlMe3), or methylaluminoxane.

[0049] In this invention, the main catalyst with the structure of formula (1) is combined with the co-catalyst. This catalyst has excellent catalytic activity and is not sensitive to water and oxygen, and can be used to prepare cyclic olefin copolymers.

[0050] Sixthly, the present invention provides a method for preparing a cyclic olefin copolymer, the method comprising the following steps:

[0051] In the presence of the composite catalyst as described in the fifth aspect, cyclic olefin monomers and α-olefins undergo a copolymerization reaction to obtain cyclic olefin copolymers.

[0052] Preferably, the cyclic olefin monomer can be one or a combination of at least two of norbornene and its derivatives, and dicyclopentadiene and its derivatives.

[0053] Preferably, the monomer of the α-olefin is one or a combination of at least two of ethylene, propylene, or butene.

[0054] Preferably, the molar ratio of the cyclic olefin monomer to the α-olefin is 1:1 to 1:5, for example, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5 or 1:5.

[0055] Preferably, the molar ratio of the main catalyst to the cyclic olefin monomer in the composite catalyst is 10. -6 :1-10 -5 :1, for example, 10 -6 1, 2×10 -6 1. 4×10 -6 1. 5×10 -6 1. 7×10 -6 1. 8×10 -6 1. 9×10 -6 :1 or 10 -5 :1.

[0056] Preferably, the amount of co-catalyst in the composite catalyst is 0.01 mol% to 1 mol% of the molar amount of the cyclic olefin monomer, for example, 0.01 mol%, 0.03 mol%, 0.05 mol%, 0.08 mol%, 0.1 mol%, 0.3 mol%, 0.5 mol%, 0.8 mol%, or 1 mol%.

[0057] Preferably, the temperature of the copolymerization reaction is 0℃-100℃, for example 0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃ or 100℃, and the time of the copolymerization reaction is 5min-60min, for example 5min, 8min, 10min, 20min, 30min, 40min, 50min or 60min.

[0058] In this invention, the copolymerization reaction is carried out in a system with a water content ≤100ppm (e.g., 0.1ppm, 0.5ppm, 1ppm, 3ppm, 5ppm, 10ppm, 20ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, or 100ppm) and an oxygen content ≤90ppm (e.g., 0.1ppm, 0.5ppm, 1ppm, 3ppm, 5ppm, 10ppm, 20ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, or 90ppm). The composite catalyst of this invention is insensitive to water and oxygen.

[0059] In a seventh aspect, the present invention provides a cyclic olefin copolymer, which is prepared by the preparation method described in the sixth aspect.

[0060] Eighthly, the present invention provides a head-up display, wherein the raw materials for preparing the head-up display include the cyclic olefin copolymers described above.

[0061] In a ninth aspect, the present invention provides a projection optical assembly, the projection optical assembly including the head-up display as described above.

[0062] Compared with the prior art, the present invention has the following beneficial effects:

[0063] The preparation method of the present invention uses nitrogen heteroatom carbene as a catalyst, which can directly react compound 1j and racemic compound 2 to obtain compound 3 directly, without converting compound 1j into a halide, or converting racemic compound 2 into an acyl chloride compound beforehand, and without resolving it into a chiral acyl chloride compound. Therefore, the reaction synthesis of the present invention is simpler and more efficient, simplifies the reaction steps, reduces the synthesis cost, and reduces the cost of synthesizing ROMP catalyst.

[0064] The catalyst of the present invention for preparing cyclic olefin copolymers can be combined with a co-catalyst for the synthesis of cyclic olefin copolymers, has high catalytic activity, and is insensitive to water and oxygen, and can be used for the preparation of optical components. Attached Figure Description

[0065] Figure 1 The 1H NMR spectrum of (-)-Berklionic acid prepared in Example 1. Detailed Implementation

[0066] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0067] The synthesis of the starting material compound 1i used in the following examples specifically includes the following steps:

[0068] S1: Synthesized compound 1j;

[0069] S1a: Synthetic compound 1d;

[0070]

[0071] At -78°C, the phosphate ester was dissolved in tetrahydrofuran at a molar ratio of 1.04:1, with a solubility of 0.2 mmol / mL. n-Butyllithium was added dropwise to the tetrahydrofuran solution at a molar ratio of 1.04:1. After the addition of n-butyllithium, the reaction was stirred for 1 hour, then allowed to warm naturally to room temperature and stirred for 9 hours. After the reaction was complete, the mixture was quenched with saturated ammonium chloride, extracted with ethyl acetate, dried over anhydrous sodium sulfate, filtered, and rotary evaporated through a column (petroleum ether to ethyl acetate ratio of 30:1) to obtain a pale yellow oily liquid in 90% yield.

[0072]

[0073] 1b was dissolved in methanol, with a solubility of 0.5 mmol / ml. Palladium on carbon was added to the methanol solution at a concentration of 0.2 g / mmol 1b. The mixture was stirred at room temperature for 3 hours under a hydrogen atmosphere at 3 MPa. After the reaction was complete, the solution was filtered, evaporated to dryness, and passed through a column (petroleum ether to ethyl acetate ratio of 30:1) to obtain a colorless oily liquid with a yield of 99%.

[0074]

[0075] Diisopropylamine was dissolved in tetrahydrofuran at -78°C, with a solubility of 2.2 mmol / ml. The molar ratio of diisopropylamine to 1c was 3.3:1. Butyllithium was added to the tetrahydrofuran solution at a molar ratio of 3:1. After addition, the mixture was stirred for 15 minutes, then allowed to naturally warm to 0°C, and stirred for another 15 minutes. 1c was then dissolved in tetrahydrofuran, with a solubility of 0.1 mmol / ml. The tetrahydrofuran solution of 1c was added to the mixture, followed by the addition of phosphate ester at a molar ratio of 1.1:1. After addition, the mixture was stirred at 0°C for 30 minutes. After stirring, paraformaldehyde was added to the reaction mixture at a rate of 600 g per millimole of 1c. After the addition of paraformaldehyde, the reaction was stirred at 0°C for 1 hour, and then quenched with saturated ammonium chloride. The sample was extracted three times with diethyl ether, washed with saturated brine, dried over anhydrous magnesium sulfate, and then evaporated to dryness and passed through a column (the ratio of petroleum ether to ethyl acetate was 5:1) to give a colorless oily liquid with a yield of 47%.

[0076] S1b: 1g of the synthesized compound;

[0077]

[0078] At room temperature, methyl 2,6-dimethylbenzoate and potassium carbonate were dissolved in N,N-dimethylformamide, and then benzyl bromide was added. The solubility of methyl 2,6-dimethylbenzoate was 0.2 mmol per mL of DMF. The molar ratio of potassium carbonate to methyl 2,6-dimethylbenzoate was 2.5:1, and the molar ratio of benzyl bromide to methyl 2,6-dimethylbenzoate was also 2.5:1. The mixture was stirred for 12 hours. After the reaction was complete, the solution was diluted with water and then extracted with ethyl acetate. The organic phase was dried over anhydrous sodium sulfate, evaporated to dryness, and then column-sected (petroleum ether to ethyl acetate ratio 30:1) to give a white solid in 89% yield.

[0079]

[0080] At room temperature, 1f was dissolved in hexafluoroisopropanol (solubility of 1f is 0.25 mol / L). N-iodosuccinimide was added to the mixture at a molar ratio of 1:1 to 1f. The mixture was stirred for 5 hours. After the reaction was complete, the solvent was evaporated, the mixture was redissolved in ethyl acetate, quenched with sodium thiosulfate, washed three times with saturated brine, dried over anhydrous sodium sulfate, and purified by column chromatography (petroleum ether to ethyl acetate ratio of 30:1) to give a white solid in 88% yield.

[0081] S1c: Synthetic compound 1i;

[0082]

[0083] In a glove box, rac-1d, 1h, 1g, palladium acetate, 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (XPhos), and potassium (±)-5-norbornene-2-carboxylate were dissolved in N-methylpyrrolidone. The solubility of rac-1d was 0.2 mol / L. The molar ratio of 1h to rac-1d was 4:1, the molar ratio of 1g to rac-1d was 1.32:1, the molar ratio of palladium acetate to rac-1d was 0.15:1, the molar ratio of XPhos to rac-1d was 0.36:1, and the molar ratio of potassium (±)-5-norbornene-2-carboxylate to rac-1d was 1:1. The reaction mixture was transferred out of the glove box and stirred at room temperature for 45 minutes. Then, the temperature was raised to 60°C and stirring was continued for 12 hours. After the reaction was complete, the mixture was allowed to cool naturally, washed with water, extracted with methyl tert-butyl ether, dried over anhydrous sodium sulfate, and filtered. The solution was then evaporated to dryness and passed through a column (petroleum ether to ethyl acetate in a 3:1 ratio) to give a pale yellow, foamy solid (M-1), with a yield of 69%.

[0084]

[0085] M-1 and cesium carbonate were dissolved in acetonitrile. The solubility of M-1 was 0.1 mol / L, and the molar ratio of cesium carbonate to M-1 was 1.5:1. The reaction was stirred at 60°C for 2 hours. After the reaction was completed, the mixture was allowed to cool naturally, washed with water, extracted with methyl tert-butyl ether, dried over anhydrous sodium sulfate, and filtered. The solution was then evaporated to dryness and passed through a column (petroleum ether to ethyl acetate ratio of 20:1) to give a light yellow oily liquid in 1 ml, with a yield of 90%.

[0086] S1d: Synthetic compound 1j

[0087]

[0088] Dissolve 1i in methanol (solubility 0.1 mol / L). Add palladium on carbon (0.1 mg / mg 1i) to the mixture. Stir at room temperature for 30 minutes under hydrogen balloon conditions. After the reaction is complete, remove the hydrogen balloon and add p-toluenesulfonic acid monohydrate to the reaction solution (molar ratio of p-toluenesulfonic acid monohydrate to 1i 10:1). Continue stirring for 12 hours. Filter the mixture, wash with ethyl acetate, and evaporate to dryness by column chromatography (petroleum ether to ethyl acetate ratio 2:1) to obtain a colorless oily liquid with a yield of 69%.

[0089] The above-mentioned synthetic reaction steps and the characterization of the substances can be obtained from the literature Angew.Chem.Int.Ed.10.1002 / anie.202014660.

[0090] Preparation Example 1

[0091] The synthesis of (-)-Berklee acid 4 in this preparation example specifically includes the following steps:

[0092]

[0093] The materials fed during the synthesis process are shown in Table 1.

[0094] Table 1

[0095]

[0096] According to the material ratios shown in Table 1, compound 2, compound 1j, arylboronic acid, dehydrogenating reagent, and nitrogen-atom carbene ligand are added. The molecular sieve was dissolved in ethyl acetate. Under nitrogen protection, the reaction was vigorously stirred at 30°C for 12 hours. After the reaction was completed, the product was evaporated to dryness and passed through a column to obtain the target product, which was a white solid. The yield of this reaction step was 61%, and the purity was 99%.

[0097] (2) Synthesis of (-)-Berklee acid 4:

[0098]

[0099] Compound 3 was dissolved in toluene under a nitrogen atmosphere. The solubility of compound 3 was 0.026 mol / L. Tributyltin oxide was then added to the mixture, with a molar ratio of tributyltin oxide to compound 3 of 14.6:1. The reaction was stirred at 115 °C for 8 hours. After the reaction was complete, the mixture was allowed to cool naturally to room temperature. It was then diluted with acetonitrile and 1M hydrochloric acid, extracted with dichloromethane, dried over anhydrous sodium sulfate, filtered, and subjected to rotary filtration through a column (petroleum ether:dichloromethane:formic acid ratio of 50:10:1) to obtain a white solid (i.e., (-)-Berklee acid 4)) in a yield of 34%. Its 1H NMR spectrum is shown below. Figure 1 As shown, the assignment of the hydrogen NMR spectrum is basically consistent with that reported in the literature. -93.4 (c=0.02, MeOH), optical rotation similar to that in the literature.

[0100] Compared with the synthetic route described in the literature (the literature reports that the total yield of berkelic acid synthesized from 1j is 13.7%), the total yield of this example is 20.74%, which is an improvement of 7.04%, and two reaction steps are omitted.

[0101] Preparation Example 2

[0102] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 2.

[0103] Table 2

[0104]

[0105] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 2. The yield of this reaction step was 77% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route described in the literature (the literature reported that the total yield of berklee acid synthesized from 1j was 13.7%), the total yield of this example was 26.18%, which is an improvement of 12.48%.

[0106] Preparation Example 3

[0107] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 3.

[0108] Table 3

[0109]

[0110] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 3. The yield of this reaction step was 82% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route described in the literature (the literature reported that the total yield of berklee acid synthesized from 1j was 13.7%), the total yield of this example was 27.88%, which is an improvement of 14.48%.

[0111] Preparation Example 4

[0112] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 4.

[0113] Table 4

[0114]

[0115]

[0116] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 4. The yield of this reaction step was 93% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route described in the literature (the literature reported that the total yield of berklee acid synthesized from 1j was 13.7%), the total yield of this example was 31.62%, which is an improvement of 17.92%.

[0117] Preparation Example 5

[0118] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 5.

[0119] Table 5

[0120]

[0121] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 5. The yield of this reaction step was 74% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route reported in the literature (the total yield of 13.7% of 1j synthesized from 1j), the total yield of this example was 25.16%, which is an improvement of 11.46%.

[0122] Preparation Example 6

[0123] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 6.

[0124] Table 6

[0125]

[0126] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 6. The yield of this reaction step was 90% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route described in the literature, the overall yield of this example was 30.6%, which is an improvement of 16.9%.

[0127] Preparation Example 7

[0128] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 7.

[0129] Table 7

[0130]

[0131] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 7. The yield of this reaction step was 93% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route described in the literature, the overall yield of this example was 31.62%, which is an improvement of 16.92%.

[0132] Preparation Example 8

[0133] Compound 3 was synthesized, and the feed ingredients during the synthesis process are shown in Table 8.

[0134] Table 8

[0135]

[0136] Compound 3 was synthesized according to the process in Preparation Example 1 and the feed table 8. The yield of this reaction step was 93% and the purity was 99%. The steps for preparing (-)-Berklee acid 4 were the same as in Preparation Example 1. Compared with the synthetic route described in the literature, the overall yield of this example was 31.62%, which is an improvement of 16.92%.

[0137] It is evident from the above preparation examples that all eight examples improved the overall yield of (-)-Berklee acid and had higher step economy.

[0138] Preparation Example 9

[0139] The preparation method of the main catalyst includes the following steps:

[0140] Under nitrogen atmosphere, 600 mg of (-)-bercrolic acid obtained in Preparation Example 4 was dissolved in 300 mL of n-hexane, and 300 mg of tungsten trichloride was dissolved in 300 mL of n-hexane. The metal chloride solution was slowly added dropwise to the bercrolic acid solution at 0 °C. After the addition was complete, the mixture was stirred at room temperature and atmospheric pressure (400 rpm) for 15 minutes. The reaction solution was then distilled under reduced pressure to obtain the desired main catalyst-1 in 99% yield and 99% purity.

[0141] Comparative Application Example 1

[0142] The preparation method of cyclic olefin copolymers specifically includes the following steps:

[0143] First, dicyclopentadiene was selectively hydrogenated using a Ni-Al2O3 catalyst to obtain 5,6-dihydrodicyclopentadiene (cycloolefin monomer-1), and then distilled to obtain cycloolefin monomer-1 with a purity greater than 99%.

[0144]

[0145] Then, continuous solution polymerization of ethylene and cycloolefin monomer-1 was carried out in a polymerization reactor with an effective volume of 500 mL at a polymerization temperature of 0 °C and a polymerization pressure of 1.0 bar. The feed per unit residence time was 1 mol of cycloolefin monomer-1, 10 mol of cyclohexane solvent (with a water content of less than 1 ppm and an oxygen content of less than 1 ppm), 2 mol of ethylene, and 0.002 mol of hydrogen. The catalyst was prepared as a cyclohexane solution and fed. The main catalyst, EtCp(Ind)ZrCl2 (purchased from Sigma-Aldrich), was fed at 1.28 μmol per unit residence time; the co-catalyst, methylaluminoxane, was fed at 2.56 mmol per unit residence time; and the polymerization residence time was 30 min. Finally, the cycloolefin copolymer COC-1 was obtained.

[0146] Comparative Application Example 2

[0147] Except for the water content in cyclohexane being 100 ppm and the oxygen content being 90 ppm, everything else was consistent with Comparative Application Example 1. A cycloolefin copolymer COC-2 was obtained.

[0148] Application Example 1

[0149] The monomer synthesis steps are the same as those in Comparative Application Example 1;

[0150] Continuous solution polymerization of ethylene and cycloolefin monomer-1 was carried out in a polymerization reactor with an effective volume of 500 mL at a polymerization temperature of 0 °C and a polymerization pressure of 1.0 bar. The feed amounts were: 1 mol of cycloolefin monomer-1 per residence time; 10 mol of cyclohexane solvent per residence time (with water and oxygen content less than 1 ppm); 2 mol of ethylene per residence time; 0.002 mol of hydrogen per residence time; 1.28 μmol of main catalyst-1 per residence time; and 2.56 mmol of methylaluminoxane cocatalyst per residence time. The polymerization residence time was 30 min. The cycloolefin copolymer COC-3 was obtained.

[0151] Application Example 2

[0152] Except that the water content in the polymerization solvent cyclohexane was 50 ppm and the oxygen content was 45 ppm, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-4 was obtained.

[0153] Application Example 3

[0154] Except that the water content in the polymerization solvent cyclohexane was 100 ppm and the oxygen content was 90 ppm, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-5 was obtained.

[0155] Application Example 4

[0156] Except for the polymerization temperature of 50°C, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-6 was obtained.

[0157] Application Example 5

[0158] Except for the polymerization temperature of 100°C, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-7 was obtained.

[0159] Application Example 6

[0160] Except for the cyclic olefin monomer-1 being fed at a unit residence time of 2.5 mol, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-8 was obtained.

[0161] Application Example 7

[0162] Except for the cyclic olefin monomer-1 being fed at a unit residence time of 5 mol, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-9 was obtained.

[0163] Application Example 8

[0164] Except for the cyclic olefin monomer-1 being fed at a unit residence time of 1.5 mol, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-10 was obtained.

[0165] Application Example 9

[0166] Except for the ethylene unit residence time feed being 1 mol, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-11 was obtained.

[0167] Application Example 10

[0168] Except for the main catalyst-1 being fed at a unit residence time of 5 mol, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-12 was obtained.

[0169] Application Example 11

[0170] Except for the main catalyst-1 being fed at a unit residence time of 8 mol, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-13 was obtained.

[0171] Application Example 12

[0172] Except for replacing methylaluminoxane with aluminum chloride, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-14 was obtained.

[0173] Application Example 13

[0174] Except for replacing methylaluminoxane with aluminum trifluoromethanesulfonate, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-15 was obtained.

[0175] Application Example 14

[0176] Except for replacing methylaluminoxane with trimethylaluminum, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-16 was obtained.

[0177] Application Example 15

[0178] Except for the polymerization time of 10 min, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-17 was obtained.

[0179] Application Example 16

[0180] Except for the polymerization time of 60 min, the other steps were the same as in Application Example 1, and the cyclic olefin copolymer COC-18 was obtained.

[0181] The cyclic olefin copolymers obtained in the above application examples were characterized as follows, and the relevant test results are summarized in Table 9 below:

[0182] (1) Reactivity: Weigh the mass of COC after the reaction and the mass of the precipitated impurities. The reactivity is: mass of COC after the reaction / (mass of COC after the reaction and mass of the precipitated impurities).

[0183] (2) Weight-average molecular weight (Mw) and molecular weight distribution (PDI): obtained by high-temperature Polymer Char GPC-IR testing;

[0184] Table 9

[0185]

[0186]

[0187] As can be seen from the data in Table 9, the catalyst activity of the present invention can reach a maximum of 80%. Application Examples 1-3 show that the catalyst activity does not change significantly with variations in the water and oxygen content of the solvent, indicating that the catalyst of the present invention is not sensitive to water and oxygen.

[0188] The applicant declares that this invention illustrates the preparation method of bercrolic acid, the cyclic olefin copolymerization catalyst prepared from bercrolic acid, and their preparation method and application through the above embodiments. However, this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials used in this invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A method for preparing (-)-Berklee acid, characterized in that, The preparation method includes the following steps: (1) In the presence of a nitrogen-atom carbene ligand, compound 1j reacts with compound 2 to give compound 3, as shown in the following reaction equation: (2) Compound 3 is hydrolyzed in the presence of a hydrolysis catalyst to give (-)-Berkley acid, as shown in the following reaction formula:

2. The preparation method according to claim 1, characterized in that, The nitrogen-heteroatom carbene ligand includes any one or a combination of at least two of the following ligands: Preferably, the molar ratio of compound 1j and compound 2 in step (1) is 1:1 to 1:5; Preferably, the molar ratio of the nitrogen-atom carbene ligand to compound 2 in step (1) is 0.1:1-0.5:1; Preferably, the reaction in step (1) is carried out in the presence of arylboronic acid; Preferably, the arylboronic acid comprises any one or a combination of at least two of the following: phenylboronic acid, 4-chlorophenylboronic acid, 4-fluorophenylboronic acid, 4-methoxyboronic acid, 4-carboxyphenylboronic acid, 1-naphthoboronic acid, 4-bromophenylboronic acid, 3-carboxyphenylboronic acid, 2-naphthoboronic acid, 4-trifluoromethylphenylboronic acid, 3-fluorophenylboronic acid, 4-tolueneboronic acid, 3-chlorophenylboronic acid, 3,5-dichlorophenylboronic acid, 3-methoxyphenylboronic acid, 4-cyanophenylboronic acid, 4-formylphenylboronic acid, 2,4-dichlorophenylboronic acid, 3,4,5-trifluorophenylboronic acid, 4-trifluoromethoxyphenylboronic acid, 2-methylphenylboronic acid, or 4-biphenylboronic acid. Preferably, the molar ratio of the arylboronic acid to compound 2 is 1:1 to 1:5; Preferably, the reaction in step (1) is carried out in the presence of a dehydrogenating agent; Preferably, the dehydrogenation reagent includes any one of sodium hydride, calcium hydride, n-butyllithium, tert-butyllithium, sodium ethoxide, sodium hydroxide, and diisopropylaminolithium; Preferably, the molar ratio of the dehydrogenating agent to compound 2 is 0.01:1 to 1:1; Preferably, the reaction in step (1) is carried out in... The process is carried out in the presence of molecular sieves; Preferably, relative to 1 mol of compound 2, the The amount of molecular sieve used is 100g-5000g; Preferably, the reaction in step (1) is carried out in a solvent selected from water, formamide, acetonitrile, methanol, ethanol, propanol, acetone, dioxane, tetrahydrofuran, methyl ethyl ketone, n-butanol, ethyl acetate, diethyl ether, isopropyl ether, dichloromethane, chloroform, bromoethane, benzene, carbon tetrachloride, carbon disulfide, cyclohexane, or n-hexane, or any combination of at least two of these solvents. Preferably, the temperature of the reaction in step (1) is 0℃-100℃, and the reaction time is 6h-12h; Preferably, the hydrolysis catalyst in step (2) is selected from one of tributyltin oxide, toluenesulfonic acid, or acetic acid; Preferably, the molar ratio of the hydrolysis catalyst to compound 3 in step (2) is 1:1-30; Preferably, the reaction in step (2) is carried out in a solvent selected from one or a combination of at least two of tetrahydrofuran, n-hexane, cyclohexane, ethyl acetate or toluene; Preferably, the reaction temperature in step (2) is 80℃-150℃ and the reaction time is 3-10h.

3. Berkley acid prepared by the preparation method according to claim 1 or 2.

4. A catalyst for preparing cyclic olefin copolymers, characterized in that, The catalyst has the structure described in formula (1): Where R1 and R2 independently represent hydrogen atom, halogen atom, cyano group, and C2-C group. 10 Alkyl groups; C1-C 10 The alkoxy group, substituted or unsubstituted C6-C20 aryloxy group, wherein R1 and R2 exist independently or are connected to each other to form a cyclic structure; the metal ion M is one of palladium, nickel, rhodium or tungsten.

5. The method for preparing the catalyst for preparing cyclic olefin copolymers according to claim 4, characterized in that, The preparation method includes the following steps: The catalyst for preparing cyclic olefin copolymers is obtained by reacting (-)-Burkliic acid with a metal chloride. Preferably, the molar ratio of (-)-Berkliic acid to metal chloride is 1:1 to 1:10; Preferably, the reaction is carried out in an organic solvent selected from at least one of cyclohexane, n-hexane, or toluene; Preferably, the reaction is carried out in an anhydrous and oxygen-free environment; Preferably, the reaction is carried out under nitrogen protection; Preferably, the metal chloride is added dropwise to the reaction system containing (-)-Berklionic acid, and the dropwise addition is carried out at -10°C to 10°C; Preferably, the reaction is carried out at room temperature after the addition is complete; the reaction time is 10 to 60 minutes. Preferably, the catalyst for preparing cyclic olefin copolymers is obtained by vacuum distillation after the reaction is completed; Preferably, the reduced pressure distillation is -0.4 bar to -1 bar, and the temperature is 25°C to 50°C.

6. A composite catalyst, characterized in that, The composite catalyst includes a main catalyst and a co-catalyst. The main catalyst is the catalyst according to claim 4, and the co-catalyst includes one or a combination of at least two of aluminum chloride, aluminum trifluoromethanesulfonate, trimethylaluminum or methylaluminoxane.

7. A method for preparing a cyclic olefin copolymer, characterized in that, The preparation method includes the following steps: In the presence of the composite catalyst described in claim 6, a copolymerization reaction is carried out between cyclic olefin monomers and α-olefins to obtain a cyclic olefin copolymer. Preferably, the cyclic olefin monomer can be one or a combination of at least two of norbornene and its derivatives, and dicyclopentadiene and its derivatives; Preferably, the monomer of the α-olefin is one or a combination of at least two of ethylene, propylene, or butene; Preferably, the molar ratio of the cyclic olefin monomer to the α-olefin is 1:1 to 1:5; Preferably, the molar ratio of the main catalyst to the cyclic olefin monomer in the composite catalyst is 10. -6 :1-10 -5 :1; Preferably, the amount of co-catalyst in the composite catalyst is 0.01 mol% to 1 mol% of the molar amount of the cyclic olefin monomer; Preferably, the temperature of the copolymerization reaction is 0℃-100℃, and the time of the copolymerization reaction is 5min-60min; Preferably, the copolymerization reaction is carried out in a system with a water content of ≤100ppm and an oxygen content of ≤90ppm.

8. A cyclic olefin copolymer, characterized in that, The cyclic olefin copolymer was prepared using the preparation method described in claim 7.

9. A head-up display, characterized in that, The raw materials for manufacturing the head-up display include the cyclic olefin copolymer of claim 8.

10. A projection optical component, characterized in that, The projection optics assembly includes the head-up display as described in claim 9.

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