Method for preparing high-purity 1, 4-dioxane-2-ketone at low cost

Abstract

The invention belongs to the field of chemistry and chemical engineering, and discloses high-purity 1, 4-dioxane-2-ketone and a preparation method thereof. A large amount of high-purity 1, 4-dioxane-2-ketone can be prepared at one time by taking a large amount of glycollic acid or glycollic acid derivatives and ethylene oxide as raw materials and adopting a one-step synthesis process route and a purification mode suitable for industrial production. According to the method, cheap bulk commodities are adopted as raw materials, and high-value conversion of low-value chemicals is achieved; according to the method disclosed by the invention, the 1, 4-dioxane-2-ketone is rapidly synthesized in one step under mild conditions without a catalyst or with a trace amount of a catalyst, so that the synthesis yield of a target product is improved, the reaction steps are greatly shortened, the energy consumption is greatly reduced, and the production cost is obviously reduced.

Description

Technical Field

[0001] The invention relates to the field of chemistry and chemical engineering, and in particular to a method for preparing high-purity 1,4-dioxane-2-one at low cost. Background Art

[0002] 1,4-dioxane-2-one (pDO for short) is a colorless crystal at room temperature, with a molecular weight of 102Da, a melting point of 26-28°C, and a boiling point of 220°C at normal pressure. pDO is an important chemical that can be used as a mildew inhibitor. In addition, it is also a monomer for synthesizing a class of biodegradable polyester materials, poly-1,4-dioxane-2-one (PpDO). The first prerequisite for preparing PpDO with excellent performance is to be able to obtain a certain scale of high-purity monomer pDO. However, pDO is still not an easily available bulk commercial product. Therefore, the development of a new pDO synthesis method and process route is a technical problem that needs to be solved urgently.

[0003] At present, there are two main methods for synthesizing pDO: one is to use diethylene glycol as raw material, and prepare pDO through catalytic oxidative dehydrogenation and cyclization reaction; the other is to use ethylene glycol as raw material, react with chloroacetic acid or chloroacetate to obtain hydroxy acid salt, and then obtain it through esterification. However, the above methods have their own advantages and disadvantages. For example, patents US2807629 and US2900395 disclose methods for synthesizing pDO based on catalytic dehydrogenation of diethylene glycol, which mainly use copper and chromium as catalysts, and the temperature usually needs to be maintained at 240-360°C, but the yield of pure pDO is only 25%. Academician Wang Yuzhong's team further optimized the reaction process, using copper and zinc compounds as catalysts, alkali, alkaline earth and rare earth metal compounds as co-catalysts, which improved the yield to a certain extent, but this method is difficult to separate and purify pDO, and the reaction device and catalyst structure are relatively complex, and the industrial production investment is large; at the same time, it is difficult to ensure that the pDO product has no heavy metal residues, which affects the subsequent catalytic ring-opening polymerization process of pDO and the application of PpDO in the medical field.

[0004] In addition, using ethylene glycol as a raw material, ethylene glycol monosodium can be prepared in the presence of metallic sodium, and then hydroxyethoxyacetic acid sodium salt can be prepared with chloroacetic acid, and after treatment such as distillation and washing, pDO can be prepared by inorganic acid acidification or high-temperature catalytic ring closure. However, this method will produce a large amount of sodium chloride during the preparation process, the steps are cumbersome and the reaction conditions are harsh; at the same time, the process route of chloroacetic acid hydrolysis is seriously corrosive to the equipment and pollutes a lot, so it cannot be mass-produced.

[0005] Therefore, it is of great significance to explore a simple pDO synthesis process, improve the yield and purity of pDO, and reduce or abandon the use of expensive catalysts or heavy metal catalysts. Summary of the invention

[0006] The embodiment of the present invention provides a method for preparing high-purity 1,4-dioxane-2-one at low cost, which can prepare high-yield and high-purity 1,4-dioxane-2-one through a one-step synthesis method.

[0007] In a first aspect, the present invention provides a method for preparing high-purity 1,4-dioxane-2-one at low cost, the method comprising:

[0008] Ethylene oxide is mixed with glycolic acid or a glycolic acid derivative, and the high-purity 1,4-dioxane-2-one is obtained after reaction; wherein the glycolic acid derivative includes glycolate or glycolic ester, and the structural formula of the glycolate is as follows:

[0009] In the formula, R is a C with a substituent 1 -C 8 Alkyl, C 3 -C 8 Cycloalkyl, aromatic or aromatic heterocyclic group, the substituent is halogen, C 1 -C 3 Alkyl, halogenated C 1 -C 3 Alkyl, C 1 -C 3 Alkoxy or hydroxy.

[0010] Preferably, before the reaction is carried out, a step of adding a catalyst to the reaction system is also included; wherein the catalyst is selected from an inorganic acid catalyst, an organic acid catalyst, an inorganic base catalyst, an organic base catalyst, a metal chloride catalyst, a metal oxide catalyst, a metal salt catalyst, an ionic liquid catalyst, a solid acid catalyst, a Lewis acid-base pair catalyst, a cation exchange resin catalyst or a molecular sieve catalyst.

[0011] Preferably, the molar ratio of the catalyst to glycolic acid or glycolic acid derivative is 1:(20-10000).

[0012] More preferably, the molar ratio of the catalyst to glycolic acid or glycolic acid derivative is 1:(100-500).

[0013] Preferably, the glycolate salt is selected from one or more of lithium glycolate, sodium glycolate, potassium glycolate, calcium glycolate, magnesium glycolate, aluminum glycolate or iron glycolate.

[0014] More preferably, the glycolic acid ester is selected from one or more of methyl glycolate, ethyl glycolate, n-propyl glycolate, isopropyl glycolate, n-butyl glycolate, isobutyl glycolate, tert-butyl glycolate, phenyl glycolate or benzyl glycolate.

[0015] Preferably, the molar ratio of ethylene oxide to glycolic acid or glycolic acid derivative is (1-10): (1-10).

[0016] More preferably, the molar ratio of ethylene oxide to glycolic acid or glycolic acid derivative is 1:(1-5).

[0017] Preferably, the inorganic acid catalyst is selected from one or more of sulfuric acid, hydrochloric acid, hydrobromic acid, tungstic acid, titanic acid, and boric acid;

[0018] The organic acid catalyst is selected from one or more of methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, boron trifluoride, boron trifluoride ethyl ether, tri(pentafluorophenyl)boron, triethylboron, camphorsulfonic acid, benzoic acid, salicylic acid, oxalic acid, and malic acid;

[0019] The inorganic base catalyst is selected from one or more of sodium carbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, lithium hydroxide, magnesium hydroxide, zinc hydroxide, copper hydroxide, iron hydroxide, and ammonium hydroxide;

[0020] The organic base catalyst is selected from one or more of triethylamine, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and hexamethyldisilazane;

[0021] The metal chloride catalyst is selected from one or more of ferric chloride, ferric chloride, zinc dichloride, tin chloride, magnesium chloride, titanium chloride, aluminum chloride, and indium chloride;

[0022] The metal oxide catalyst is selected from one or more of iron oxide, ferroferric oxide, copper oxide, magnesium oxide, zinc oxide, aluminum oxide, calcium oxide, and titanium oxide;

[0023] The metal salt catalyst is selected from one or more of copper tetrafluoroborate, bismuth trifluoride, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, calcium carbonate, cesium carbonate, sodium glycolate, sodium acetate, lithium diisopropylamide, sodium methoxide, sodium ethoxide, sodium tert-butoxide, potassium tert-butoxide, n-butyl lithium, and isobutyl lithium;

[0024] The ionic liquid catalyst is selected from one or more of imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium salt ionic liquids, and quaternary phosphonium salt ionic liquids;

[0025] The Lewis acid-base catalyst is obtained by mixing a Lewis acid and a Lewis base; wherein the Lewis acid is selected from one or more of methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, boron trifluoride, boron trifluoride ethyl ether, tri(pentafluorophenyl)boron, triethylboron, camphorsulfonic acid, benzoic acid, ferric chloride, ferric chloride, zinc dichloride, tin chloride, magnesium chloride, titanium chloride, aluminum chloride, indium chloride, and diethylzinc; and the Lewis base is selected from one or more of triethylamine, ammonia monohydrate, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, hexamethyldisilazane, and carbene;

[0026] The cation exchange resin is selected from one or more of a strongly acidic styrene-based cation exchange resin, a weakly acidic styrene-propylene-based cation exchange resin, a styrene divinyl benzene resin, and an acrylic acid-based cation exchange resin;

[0027] The molecular sieve catalyst is selected from one or more of zirconium sulfate molecular sieve, β molecular sieve, LaY molecular sieve, TS-1 molecular sieve, USY molecular sieve, and ZSM-5 molecular sieve.

[0028] More preferably, the catalyst is selected from an inorganic acid catalyst, an organic acid catalyst, a metal chloride catalyst, a metal oxide catalyst, a metal salt catalyst, a solid acid catalyst or a Lewis acid-base pair catalyst.

[0029] Preferably, the reaction temperature is -50 to 100°C and the reaction time is 10 to 60 minutes.

[0030] Preferably, after the reaction is completed, the method further comprises the steps of filtering, washing, distilling and crystallizing the crude product obtained by the reaction in sequence.

[0031] In a second aspect, the present invention provides a high-purity 1,4-dioxane-2-one prepared by any of the methods described in the first aspect.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects:

[0033] (1) In the present invention, by using glycolic acid or glycolic acid derivatives and ethylene oxide as raw materials and adopting a one-step synthesis process route, high-purity 1,4-dioxane-2-one can be prepared in large quantities at one time. The reaction raw materials used are all low-cost bulk chemicals, which reduces product costs, has high added value, and has a wide source of raw materials, avoiding the problem of being restricted by the source of raw materials. This provides a practical method for the industrial production of 1,4-dioxane-2-one;

[0034] (2) 1,4-dioxane-2-one is prepared by a one-step method, which avoids complex synthesis processes and harsh reaction conditions, has a short reaction time, a high yield, and low energy consumption; and the reaction is carried out under air conditions, which reduces the use of inert gas. At the same time, the reaction conditions are normal pressure, which reduces safety hazards;

[0035] (3) In a preferred embodiment, the reaction process of ethylene oxide and glycolic acid or glycolic acid derivatives is catalyzed by a catalyst, which can further accelerate the reaction rate, improve the reaction yield, and reduce the production cost of 1,4-dioxane-2-one. In addition, the catalysts used are bulk chemicals, have no heavy metal residues, are less corrosive to synthesis equipment, and are suitable for large-scale industrial production conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 is a nuclear magnetic resonance spectrum of high-purity 1,4-dioxane-2-one provided in Example 11 of the present invention;

[0038] Figure 2 is an infrared spectrum of a high-purity 1,4-dioxane-2-one provided in Example 11 of the present invention; wherein the abscissa is the wave number and the ordinate is the transmittance;

[0039] Figure 3 This is a melting point test spectrum of high-purity 1,4-dioxane-2-one provided in Example 11 of the present invention; wherein the abscissa is temperature and the ordinate is heat flow rate. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0041] Ethylene oxide is the simplest ternary ether compound, mainly used to produce reagents such as ethylene glycol, surfactants, ethanolamine and ethylene glycol ethers. It is also widely used in the synthesis of daily chemicals, medicines, pesticides and polyether polyols, and can also be used as a disinfectant for high-end medical devices. Glycolic acid is an important high value-added chemical, widely used in industrial cleaning agents, daily chemical raw materials, electroplating surface treatment liquids, bactericides and biodegradable materials. In addition, glycolic acid esters, as glycolic acid derivatives, have better solubility and stability, and have the chemical properties of both alcohols and esters. They can undergo hydrolysis, oxidation, reduction, carbonylation, amination and alcoholysis reactions. As an important bulk chemical raw material, they are widely used in chemical, pharmaceutical and pesticide fields.

[0042] Selifonov Sergey A. used lactic acid ester and epoxide as raw materials to synthesize six-membered heterocyclic ether esters by the method of epoxy ring opening-saponification hydrolysis-condensation ring formation. The method firstly catalyzes lactic acid ester and epoxide to synthesize 2-(2-hydroxyethyl)-propionic acid ester intermediate, then performs base-catalyzed saponification or esterase-catalyzed hydrolysis on the intermediate to synthesize 2-(2-hydroxyethyl)-propionic acid, and finally synthesizes six-membered heterocyclic ether ester by hydroxycarboxyl condensation. However, although this method can prepare cyclic ether ester monomers, the synthesis process is too complicated, and the seven-membered ring is thermodynamically unstable, so it is difficult to achieve ring formation by one-step reaction of hydroxy ester and epoxide; at the same time, the presence of methyl in lactic acid ester may hinder the nucleophilic process of hydroxyl, so it is also necessary to adopt a step-by-step method and use a condensation reagent for ring formation.

[0043] Leyva-Perez has used nano-titanium dioxide to catalyze water and primary and secondary alcohols to complete the hydration and alkoxylation of epoxy compounds, and used glycolic acid and several epoxides to selectively synthesize 1,4-dioxane-2-one derivatives. However, the nano-titanium dioxide used as a catalyst has a high manufacturing cost, and the catalyst occupies 40% of the mass fraction of the reaction substrate. Since titanium dioxide is not resistant to water and oxygen, high-pressure nitrogen is required for the reaction; due to the low catalytic activity of titanium dioxide, a high temperature reaction of more than 120°C is required; the reaction requires the addition of an organic solvent, and it is difficult to apply to large-scale synthesis.

[0044] Based on the above problems, in order to reduce the production cost of pDO, the present invention considers using bulk chemicals such as glycolic acid and its derivatives and ethylene oxide as raw materials to develop a simple pDO synthesis process, which can not only reduce the production cost of pDO, but also realize the high-value utilization of low-value chemicals, which has important strategic significance and economic value for meeting market demand and developing new biodegradable materials.

[0045] like Figure 1As shown, the present invention provides a method for preparing high-purity 1,4-dioxane-2-one at low cost, the method comprising:

[0046] Ethylene oxide is mixed with glycolic acid or a glycolic acid derivative, and the high-purity 1,4-dioxane-2-one is obtained after reaction; wherein the glycolic acid derivative includes glycolate or glycolic ester, and the structural formula of the glycolate is as follows:

[0047] In the formula, R is a C with a substituent 1 -C 8 Alkyl, C 3 -C 8 Cycloalkyl, aromatic or aromatic heterocyclic group, the substituent is halogen, C 1 -C 3 Alkyl, halogenated C 1 -C 3 Alkyl, C 1 -C 3 Alkoxy or hydroxy.

[0048] In the embodiment of the present invention, glycolic acid or glycolic acid derivatives and ethylene oxide are used as raw materials, and the reaction temperature is controlled so that the above reactants themselves undergo self-catalysis under the interaction of hydrogen bonds. In addition, the carboxylic acid group in glycolic acid can act as a catalyst to achieve a self-catalytic reaction. In this way, a one-step synthesis process route can be used to prepare high-purity 1,4-dioxane-2-one in large quantities at one time. The reaction raw materials used are all low-cost bulk chemicals, which reduces product costs, has high added value, and has a wide source of raw materials, avoiding the problem of being restricted by the source of raw materials, thereby providing a practical method for the industrial production of 1,4-dioxane-2-one.

[0049] Taking glycolic acid derivatives as glycolic acid esters as an example, the synthetic route of 1,4-dioxane-2-one is as follows:

[0050]

[0051] It can be seen from the above reaction formula that using bulk chemicals glycolic acid ester and ethylene oxide as reaction raw materials, since glycolic acid ester contains hydroxyl groups that can participate in the reaction, it can undergo a ring-opening reaction with ethylene oxide, and the glycolic acid ester contains ester bonds that can undergo intramolecular ester exchange reactions, thereby forming 1,4-dioxane-2-one through a one-step cascade reaction.

[0052] In the examples of the present invention, a large number of studies were conducted on the route design for synthesizing pDO from glycolic acid or glycolic acid derivatives and epoxides, and it was found that glycolic acid or glycolic acid derivatives without any substituents can react with ethylene oxide in a one-step reaction to obtain pDO, and through comprehensive control and selection of the selection of various reaction raw materials, the selection of catalyst types, the process reaction conditions, the synthesis scale, etc., the synthesis process flow and production cost of pDO are greatly reduced.

[0053] It should be noted that in the embodiments of the present invention, ethylene oxide can be in a liquid state, a gaseous state or configured as a solution dissolved in an organic solvent; when ethylene oxide is a solution, the organic solvent is selected from one or more of tetrahydrofuran, dioxane, ether, dichloromethane, dichloroethane, chloroform, carbon tetrachloride, toluene, xylene, and trimethylbenzene.

[0054] According to some preferred embodiments, the glycolate salt is selected from one or more of lithium glycolate, sodium glycolate, potassium glycolate, calcium glycolate, magnesium glycolate, aluminum glycolate or iron glycolate; the glycolate ester is selected from one or more of methyl glycolate, ethyl glycolate, n-propyl glycolate, isopropyl glycolate, n-butyl glycolate, isobutyl glycolate, tert-butyl glycolate, phenyl glycolate or benzyl glycolate.

[0055] In the embodiment of the present invention, when the glycolic acid salt and glycolic acid ester in the glycolic acid derivative are of the above types, it is more conducive to quickly synthesizing a large amount of 1,4-dioxane-2-one through reaction with ethylene oxide.

[0056] According to some preferred embodiments, the molar ratio of ethylene oxide to glycolic acid or glycolic acid derivative is (1-10):(1-10) (for example, it can be 1:1, 1:2, 1:5, 1:8, 1:10, 5:1, 8:1, 10:1, 5:2, 5:5, 8:5 or 10:10).

[0057] The experiment of the present invention confirms that due to the competitive ethylene oxide ring-opening polymerization side reaction in the reaction process of ethylene oxide and glycolic acid or glycolic acid derivatives, by-products such as polyethylene glycol oligomers are generated, which makes purification difficult and reduces the effective conversion rate of ethylene oxide. Therefore, in the embodiment of the present invention, the molar ratio of ethylene oxide to glycolic acid or glycolic acid derivatives is reasonably controlled by screening the temperature, feeding method and reaction method, that is, using room temperature or low temperature, slow dropwise addition, shortening the reaction time, etc., and finally achieving the significant reduction of side reactions under the condition of low proportion of glycolic acid or glycolic acid derivatives; in the embodiment of the present invention, the molar ratio of ethylene oxide to glycolic acid or glycolic acid derivatives is further preferably 1: (1-5), and an excess of glycolic acid or glycolic acid derivatives is used to inhibit the occurrence of side reactions, thereby reducing the generation of by-products such as oligomeric polyethers during the reaction, and further facilitating the acquisition of high yield and high purity 1,4-dioxane-2-one.

[0058] According to some preferred embodiments, the step of adding a catalyst to the reaction system is also included before the reaction; wherein the catalyst is selected from an inorganic acid catalyst, an organic acid catalyst, an inorganic base catalyst, an organic base catalyst, a metal chloride catalyst, a metal oxide catalyst, a metal salt catalyst, an ionic liquid catalyst, a solid acid catalyst, a Lewis acid-base pair catalyst, a cation exchange resin catalyst or a molecular sieve catalyst.

[0059] The present invention has been experimentally confirmed that when ethylene oxide reacts with glycolic acid or glycolic acid derivatives, adding a trace amount of a series of low-cost chemicals such as inorganic acids, organic acids, inorganic bases, organic bases, metal chlorides, metal oxides, metal salts and ionic liquids as catalysts can significantly reduce the reaction temperature, accelerate the reaction rate, and reduce the reaction time, thereby increasing the reaction yield and reducing the production cost.

[0060] According to some preferred embodiments, the inorganic acid catalyst is selected from one or more of sulfuric acid, hydrochloric acid, hydrobromic acid, tungstic acid, titanic acid, and boric acid;

[0061] The organic acid catalyst is selected from one or more of methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, boron trifluoride, boron trifluoride ethyl ether, tri(pentafluorophenyl)boron, triethylboron, camphorsulfonic acid, benzoic acid, salicylic acid, oxalic acid, and malic acid;

[0062] The inorganic base catalyst is selected from one or more of sodium carbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, lithium hydroxide, magnesium hydroxide, zinc hydroxide, copper hydroxide, iron hydroxide, and ammonium hydroxide;

[0063] The organic base catalyst is selected from one or more of triethylamine, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and hexamethyldisilazane;

[0064] The metal chloride catalyst is selected from one or more of ferric chloride, ferric chloride, zinc chloride, tin chloride, magnesium chloride, titanium chloride, aluminum chloride, and indium chloride; the metal oxide catalyst is selected from one or more of ferric oxide, ferroferric oxide, copper oxide, magnesium oxide, zinc oxide, aluminum oxide, calcium oxide, and titanium oxide;

[0065] The metal salt catalyst is selected from one or more of copper tetrafluoroborate, bismuth trifluoride, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, calcium carbonate, cesium carbonate, sodium glycolate, sodium acetate, lithium diisopropylamide, sodium methoxide, sodium ethoxide, sodium tert-butoxide, potassium tert-butoxide, n-butyl lithium, and isobutyl lithium;

[0066] The ionic liquid catalyst is selected from one or more of imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium salt ionic liquids, and quaternary phosphonium salt ionic liquids;

[0067] The Lewis acid-base catalyst is obtained by mixing a Lewis acid and a Lewis base; wherein the Lewis acid is selected from one or more of methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, boron trifluoride, boron trifluoride ethyl ether, tri(pentafluorophenyl)boron, triethylboron, camphorsulfonic acid, benzoic acid, ferric chloride, ferric chloride, zinc dichloride, tin chloride, magnesium chloride, titanium chloride, aluminum chloride, indium chloride, and diethylzinc; and the Lewis base is selected from one or more of triethylamine, ammonia monohydrate, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, hexamethyldisilazane, and carbene;

[0068] The cation exchange resin is selected from one or more of a strongly acidic styrene-based cation exchange resin, a weakly acidic styrene-propylene-based cation exchange resin, a styrene divinyl benzene resin, and an acrylic acid-based cation exchange resin;

[0069] The molecular sieve catalyst is selected from one or more of zirconium sulfate molecular sieve, β molecular sieve, LaY molecular sieve, TS-1 molecular sieve, USY molecular sieve, and ZSM-5 molecular sieve.

[0070] According to some preferred embodiments, the catalyst is selected from an inorganic acid catalyst, an organic acid catalyst, a metal chloride catalyst, a metal oxide catalyst, a metal salt catalyst, a solid acid catalyst or a Lewis acid-base pair catalyst.

[0071] In an embodiment of the present invention, a large number of catalysts are first screened and it is found that the above-mentioned types of catalysts can further effectively catalyze the reaction of ethylene oxide with glycolic acid or glycolic acid derivatives. Then, a series of conditions such as temperature, feed ratio, reaction mode, etc. are comprehensively controlled so that the catalyst can maintain high catalytic activity even when the amount used is small (the amount used is less than 1%). In this way, not only the reaction temperature and reaction time can be significantly lowered, but also the purification difficulty and catalyst residue can be further reduced while ensuring a lower cost.

[0072] According to some preferred embodiments, the molar ratio of the catalyst to glycolic acid or glycolic acid derivative is 1:(20-10000) (for example, it can be 1:20, 1:50, 1:100, 1:500, 1:1000, 1:5000 or 1:10000).

[0073] In the embodiments of the present invention, the specific dosage of different catalysts can be adjusted within the above range according to the activity of each catalyst. High-activity catalysts (such as inorganic acids, organic acids, metal chlorides and other catalysts) can exert better catalytic effects at lower contents, while low-activity catalysts (such as metal salts, organic bases, inorganic bases and other catalysts) need to be at higher contents to have better catalytic effects; at the same time, when selecting catalysts, the activity time of the catalyst should also be considered (such as solid acid catalysts can be used repeatedly). Generally speaking, the more the same catalyst is used within a certain range, the higher the catalytic activity and the faster the reaction; however, for some catalysts (such as strongly acidic inorganic acids, strongly alkaline non-polar bases, etc.), exceeding a certain amount will cause side reactions. Therefore, in the embodiments of the present invention, the principle of minimum cost is followed, and the molar ratio of the catalyst to glycolic acid or glycolic acid derivatives is controlled, so that the reaction efficiency of ethylene oxide and glycolic acid or glycolic acid derivatives can be better promoted by using less catalyst.

[0074] The synthesis method in the embodiment of the present invention can be carried out under solvent-free conditions, but when the raw material used in the reaction process is solid glycolic acid, the use of a solvent to increase the solubility of the reaction system is beneficial to the reaction, and different organic solvents can be used for the synthesis reaction; when a solvent is used, a solvent that does not contain a large amount of water, alcohol, amine, or ester is used as much as possible to avoid competitive reactions to produce by-products; for example, various alkanes, aromatic hydrocarbons, ethers, and chlorine-containing solvents can be used, specifically one or more selected from n-hexane, cyclohexane, tetrahydrofuran, ether, dioxane, toluene, trimethylbenzene, dichloromethane, dichloroethane, and carbon tetrachloride.

[0075] According to some preferred embodiments, the reaction temperature is -50 to 100°C (for example, -50°C, -10°C, 0°C, 10°C, 20°C, 30°C, 50°C, 80°C or 100°C), and the reaction time is 10-60 min (for example, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min).

[0076] The synthesis method in the embodiment of the present invention has a wide temperature range. When no catalyst is added, the reaction can be promoted by increasing the temperature; when a catalyst is added, the reaction can be carried out at room temperature. The reaction process will spontaneously generate heat to accelerate the reaction. No heating or cooling device is required. The reaction can be completed within 10-30 minutes and a high conversion rate can be achieved, which greatly reduces energy consumption and device costs. At the same time, the synthesis process is carried out under normal pressure air conditions, avoiding the use of high-pressure reaction equipment and inert gas, and ensuring the safety of the synthesis process.

[0077] According to some preferred embodiments, after the reaction is completed, the steps of filtering, washing, distilling and crystallizing the crude product obtained by the reaction are further included.

[0078] In the embodiment of the present invention, after the reaction is completed, the above method can be used to separate and purify the crude product obtained by the reaction, so as to obtain high-purity 1,4-dioxane-2-one; wherein the specific process parameters of filtration, washing, distillation, and crystallization can be adjusted according to actual needs.

[0079] The present invention also provides high-purity 1,4-dioxane-2-one, which is prepared by the low-cost preparation method provided by the present invention.

[0080] In summary, in the embodiments of the present invention, 1,4-dioxane-2-one is synthesized by a one-step method using bulk products ethylene oxide, glycolic acid or glycolic acid derivatives as reaction raw materials. By reasonably controlling the types and proportions of the raw materials during the reaction, the by-products in the reaction process are less, the final yield is significantly higher than the yield in the prior art (>70%), and the energy consumption and production costs are greatly reduced; the product is purified by distillation, crystallization or sublimation, which further ensures the high purity and high yield of the product. The yield of 1,4-dioxane-2-one is 30-99%, the purity exceeds 99.5%, and the process conditions of the present invention are suitable for large-scale product purification and actual industrial production.

[0081] In order to more clearly illustrate the technical solution and advantages of the present invention, a method for preparing high-purity 1,4-dioxane-2-one at low cost is described in detail through several embodiments below.

[0082] Embodiment 1:

[0083] In an air atmosphere, add 103g glycolic acid (1.35mol), 150mL tetrahydrofuran solution of ethylene oxide (3mol / L, 0.45mol ethylene oxide) and 100mL tetrahydrofuran to a reaction bottle, stir and react at 60°C for 30 minutes, and evaporate tetrahydrofuran at 60°C after the reaction is completed. Dissolve the product with dichloromethane, filter to remove excess glycolic acid, wash twice with saturated sodium bicarbonate aqueous solution to remove residual glycolic acid, and after completion, distill under reduced pressure at 90-100°C to obtain 1,4-dioxane-2-one; the yield calculated by weighing method is 43.7%, and the purity is measured by high performance liquid chromatography and nuclear magnetic resonance hydrogen spectrum to be ~98%.

[0084] Embodiment 2:

[0085] In an air atmosphere, 103 g of glycolic acid (1.35 mol), 150 mL of a tetrahydrofuran solution of ethylene oxide (3 mol / L, 0.45 mol of ethylene oxide) and 100 mL of tetrahydrofuran were added to a reaction flask, and 0.72 mL of a catalyst (concentrated sulfuric acid (0.04 mol)) was added. The mixture was stirred at room temperature (25°C) for 30 minutes. After the reaction was completed, tetrahydrofuran was evaporated. The product was dissolved in dichloromethane, and the excess glycolic acid was filtered out. The residual glycolic acid was washed twice with a saturated sodium bicarbonate aqueous solution to remove the residual glycolic acid. After completion, 1,4-dioxane-2-one was obtained by reduced pressure distillation at 90-100°C with a yield of 55.6% and a purity of ~99%.

[0086] Example 3

[0087] In an air atmosphere, add 103g glycolic acid (1.35mol), 450mL tetrahydrofuran solution of ethylene oxide (3mol / L, 1.35mol ethylene oxide) and 100mL tetrahydrofuran to a reaction bottle, add 0.72mL catalyst (concentrated sulfuric acid (0.04mol)), stir at room temperature for 30 minutes, and evaporate tetrahydrofuran after the reaction is completed. Dissolve the product with dichloromethane, filter to remove excess glycolic acid, wash twice with saturated sodium bicarbonate aqueous solution to remove residual glycolic acid, and after completion, distill under reduced pressure at 90-100°C to obtain 1,4-dioxane-2-one with a yield of 40.0% and a purity of ~99%.

[0088] Example 4

[0089] In an air atmosphere, 103 g glycolic acid (1.35 mol) and 22.5 mL ethylene oxide (0.45 mol) were added to the reaction bottle and stirred at 60°C for 30 minutes. The product was dissolved in dichloromethane, the excess glycolic acid was filtered out, and the residual glycolic acid was washed twice with a saturated sodium bicarbonate aqueous solution to remove the residual glycolic acid. After completion, 1,4-dioxane-2-one was obtained by reduced pressure distillation at 90-100°C with a yield of 60.1% and a purity of 95%.

[0090] Example 5

[0091] In an air atmosphere, 103 g glycolic acid (1.35 mol) and 67 mL ethylene oxide (1.35 mol) were added to the reaction bottle and stirred at 60°C for 30 minutes. The product was dissolved in dichloromethane, the excess glycolic acid was filtered out, and the residual glycolic acid was washed twice with a saturated sodium bicarbonate aqueous solution to remove the residual glycolic acid. After completion, 1,4-dioxane-2-one was obtained by reduced pressure distillation at 90-100°C with a yield of 52.5% and a purity of 97%.

[0092] Example 6

[0093] Under air atmosphere, add 174mL of methyl glycolate (2.25mol) and 150mL of tetrahydrofuran solution of ethylene oxide (3mol / L, 0.45mol ethylene oxide) into the reaction bottle, add 1.2mL of concentrated sulfuric acid (22.5mmol), stir at room temperature for 10 minutes, evaporate tetrahydrofuran after the reaction is completed, and then recover methyl glycolate by vacuum distillation at 50-60℃. After completion, heat to 90-100℃ and vacuum distill to obtain 1,4-dioxane-2-one with a yield of 69.7% and a purity of>99%.

[0094] Example 7

[0095] Under air atmosphere, add 174mL of methyl glycolate (2.25mol) and 450mL of tetrahydrofuran solution of ethylene oxide (3mol / L, 1.35mol ethylene oxide) into the reaction bottle, add 1.2mL of concentrated sulfuric acid (22.5mmol), stir at room temperature for 10 minutes, evaporate tetrahydrofuran after the reaction is completed, and then distill methyl glycolate under reduced pressure at 50-60°C. After completion, heat to 90-100°C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 62% and a purity of>99%.

[0096] Example 8

[0097] Under air atmosphere, add 174 mL of methyl glycolate (2.25 mol) and 22.5 mL of ethylene oxide (0.45 mol) into the reaction bottle, add 1.2 mL of concentrated sulfuric acid (22.5 mmol), stir at room temperature for 10 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C, and then heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 76% and a purity of >99%.

[0098] Example 9

[0099] Under air atmosphere, add 174mL methyl glycolate (2.25mol) and 11.5mL ethylene oxide (0.23mol) into the reaction bottle, add 0.6mL concentrated sulfuric acid (11.3mmol), stir at room temperature for 10 minutes, evaporate tetrahydrofuran after the reaction is completed, and then recover methyl glycolate by vacuum distillation at 50-60℃. After completion, heat to 90-100℃ and vacuum distill to obtain 1,4-dioxane-2-one, with a yield of 99% and a purity of>99%.

[0100] Example 10

[0101] In an air atmosphere, 174 mL of methyl glycolate (2.25 mol) and 22.5 mL of ethylene oxide (0.45 mol) were added to the reaction flask, and 100 μL of a catalyst (boron trifluoride ether solution (46.5% BF 3 )), stirring at room temperature for 10 minutes, then distilling methyl glycolate under reduced pressure at 50-60°C, heating to 90-100°C and distilling under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 83% and a purity of>99%.

[0102] Embodiment 11

[0103] In an air atmosphere, 174 mL of methyl glycolate (2.25 mol) and 11.5 mL of ethylene oxide (0.23 mol) were added to the reaction flask, and 50 μL of a catalyst (boron trifluoride ether solution (46.5% BF 3 )), stirring at 0°C for 30 minutes, then distilling methyl glycolate under reduced pressure at 50-60°C, heating to 90-100°C and distilling under reduced pressure to obtain 1,4-dioxane-2-one, with a yield of 95% and a purity of>99%.

[0104] pass Figure 1 The H-NMR spectrum test attributed all chemical shift signals, and the integrated area ratio of the three groups of peaks was 2:2:2, corresponding to the three methylene structures respectively; Figure 2 Fourier infrared test 1750cm -1 and 1200cm -1 The signals on the left and right correspond to the stretching vibrations of the ester and ether bonds of pDO, respectively, proving the structures of the ester and ether bonds; Figure 3 This shows that pDO is in a solid state at room temperature and has a melting point of around 32°C, providing a temperature reference for melt polymerization; the above results prove that the product is indeed a pDO structure.

[0105] Example 12

[0106] Under air atmosphere, add 174mL methyl glycolate (2.25mol) and 22.5mL ethylene oxide (0.45mol) into the reaction bottle, add 3.6g catalyst (ferric chloride (22.5mmol)), stir at room temperature for 10 minutes, then distill methyl glycolate under reduced pressure at 50-60℃, and then heat to 90-100℃ and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 81% and a purity of >99%.

[0107] Embodiment 13

[0108] Under air atmosphere, add 174mL methyl glycolate (2.25mol) and 11.5mL ethylene oxide (0.23mol) into the reaction bottle, add 1.8g catalyst (ferric chloride (11.3mmol)), stir at room temperature for 10 minutes, then distill methyl glycolate under reduced pressure at 50-60℃, and then heat to 90-100℃ and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 81% and a purity of >99%.

[0109] Embodiment 14

[0110] Under air atmosphere, add 174mL methyl glycolate (2.25mol) and 22.5mL ethylene oxide (0.45mol) into the reaction bottle, add 3.9g catalyst (p-toluenesulfonic acid (22.5mmol)), stir at 0℃ for 10 minutes, stir at room temperature for 10 minutes, then distill methyl glycolate under reduced pressure at 50-60℃, after completion, heat to 90-100℃ and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 98% and a purity of >99%.

[0111] Embodiment 15

[0112] Under air atmosphere, add 174 mL of methyl glycolate (2.25 mol) and 112 mL of ethylene oxide (2.25 mol) into the reaction bottle, add 3.6 g of catalyst (ferric chloride (22.5 mmol)), stir at room temperature for 10 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C. After completion, heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 41% and a purity of >99%.

[0113] Example 16

[0114] In an air atmosphere, 174 mL of methyl glycolate (2.25 mol) and 112 mL of ethylene oxide (2.25 mol) were added to a reaction flask, and 100 μL of a catalyst (boron trifluoride ether solution (46.5% BF 3)), stirring at room temperature for 10 minutes, then distilling methyl glycolate under reduced pressure at 50-60°C, heating to 90-100°C and distilling under reduced pressure to obtain 1,4-dioxane-2-one, with a yield of 23% and a purity of 97%.

[0115] Embodiment 17

[0116] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 0.44 mL of catalyst (trifluoromethanesulfonic acid (5 mmol)), stir at room temperature for 5 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C. After completion, heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 59% and a purity of >99%.

[0117] Embodiment 18

[0118] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 2.6 g of catalyst (tri(pentafluorophenyl)boron (5 mmol)), stir at room temperature for 5 minutes, then distill methyl glycolate under reduced pressure at 50-60 °C, and after completion, heat to 90-100 °C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 73% and a purity of >99%.

[0119] Embodiment 19

[0120] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 0.5 g of catalyst (sodium carbonate (5 mmol)), stir at 50 ° C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C, and then heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 18% and a purity of >99%.

[0121] Embodiment 20

[0122] Under air atmosphere, add 77mL of methyl glycolate (1.0mol) and 9.8mL of ethylene oxide (0.2mol) into the reaction bottle, add 0.8g of catalyst (1,8-diazabicyclo[5.4.0]undec-7-ene (5mmol)), stir at 50°C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60°C, and after completion, heat to 90-100°C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 28% and a purity of >99%.

[0123] Embodiment 21

[0124] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 2.4 g of catalyst (aluminum trifluoromethylsulfonate (5 mmol)), stir at 0°C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60°C, and after completion, heat to 90-100°C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 48% and a purity of >99%.

[0125] Embodiment 22

[0126] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 1.3 g of catalyst (copper tetrafluoroborate (5 mmol)), stir at 0°C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60°C, and after completion, heat to 90-100°C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 71% and a purity of >99%.

[0127] Embodiment 23

[0128] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 1.1 g of catalyst (indium trichloride (5 mmol)), stir at 50 ° C for 180 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C, and then heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 62% and a purity of >99%.

[0129] Embodiment 24

[0130] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 0.9 g of catalyst (antimony trifluoride (5 mmol)), stir at room temperature for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C. After completion, heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 43% and a purity of >99%.

[0131] Embodiment 25

[0132] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 1.8 g of catalyst (zirconium sulfate tetrahydrate (5 mmol)), stir at 50 ° C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C, and then heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 53% and a purity of >99%.

[0133] Embodiment 26

[0134] Under air atmosphere, add 77mL methyl glycolate (1.0mol) and 9.8mL ethylene oxide (0.2mol) into the reaction bottle, add 2.0g catalyst (1-ethyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide) (5mmol), stir at room temperature for 10 minutes, then distill methyl glycolate under reduced pressure at 50-60°C, and after completion, heat to 90-100°C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 45% and a purity of >99%.

[0135] Embodiment 27

[0136] Under air atmosphere, 0.7 mL of triethylamine (5 mmol) and 0.86 g of p-toluenesulfonic acid (5 mmol) were mixed in a bottle to prepare a Lewis acid-base catalyst, and then 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) were added to the reaction bottle. The mixture was stirred at room temperature for 10 minutes, and then the methyl glycolate was distilled under reduced pressure at 50-60 ° C. After completion, the temperature was raised to 90-100 ° C and distilled under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 44% and a purity of >99%.

[0137] Embodiment 28

[0138] Under air atmosphere, add 77mL methyl glycolate (1.0mol) and 9.8mL ethylene oxide (0.2mol) into the reaction bottle, add 5g catalyst (strong acid cation exchange resin Amberlyst-15), stir at 100℃ for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60℃, and then heat to 90-100℃ and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 59% and a purity of >99%.

[0139] Embodiment 29

[0140] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 5 g of β-type molecular sieve, stir at 100 ° C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C, and then heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 43% and a purity of >99%.

[0141] Embodiment 30

[0142] Under air atmosphere, add 77 mL of methyl glycolate (1.0 mol) and 9.8 mL of ethylene oxide (0.2 mol) into the reaction bottle, add 10 g of catalyst (ZSM-5-molecular sieve), stir at 100 ° C for 30 minutes, then distill methyl glycolate under reduced pressure at 50-60 ° C, and then heat to 90-100 ° C and distill under reduced pressure to obtain 1,4-dioxane-2-one with a yield of 63% and a purity of >99%.

[0143] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing high-purity 1,4-dioxane-2-one at low cost, characterized in that: The method comprises: mixing ethylene oxide with glycolic acid or a glycolic acid derivative, and obtaining the high-purity 1,4-dioxane-2-one after reaction; wherein the glycolic acid derivative comprises glycolate or glycolate ester, and the structural formula of the glycolate ester is as follows: In the formula, R is a C1-C8 alkyl group, a C3-C8 cycloalkyl group, an aromatic group or an aromatic heterocyclic group having a substituent, and the substituent is a halogen, a C1-C3 alkyl group, a halogenated C1-C3 alkyl group, a C1-C3 alkoxy group or a hydroxyl group.

2. The method according to claim 1, characterized in that Before the reaction is carried out, the method further includes the step of adding a catalyst to the reaction system; wherein the catalyst is selected from an inorganic acid catalyst, an organic acid catalyst, an inorganic base catalyst, an organic base catalyst, a metal chloride catalyst, a metal oxide catalyst, a metal salt catalyst, an ionic liquid catalyst, a solid acid catalyst, a Lewis acid-base pair catalyst, a cation exchange resin catalyst or a molecular sieve catalyst.

3. The method according to claim 2, characterized in that: The molar ratio of the catalyst to glycolic acid or glycolic acid derivative is 1:(20-10000).

4. The method according to claim 1 or 2, characterized in that: The glycolate is selected from one or more of lithium glycolate, sodium glycolate, potassium glycolate, calcium glycolate, magnesium glycolate, aluminum glycolate or ferric glycolate; and / or The glycolate ester is selected from one or more of methyl glycolate, ethyl glycolate, n-propyl glycolate, isopropyl glycolate, n-butyl glycolate, isobutyl glycolate, tert-butyl glycolate, phenyl glycolate or benzyl glycolate.

5. The method according to claim 1 or 2, characterized in that: The molar ratio of ethylene oxide to glycolic acid or glycolic acid derivative is (1-10): (1-10); Preferably, the molar ratio of ethylene oxide to glycolic acid or glycolic acid derivative is 1:(1-5).

6. The method according to claim 2, characterized in that: The inorganic acid catalyst is selected from one or more of sulfuric acid, hydrochloric acid, hydrobromic acid, tungstic acid, titanic acid, and boric acid; The organic acid catalyst is selected from one or more of methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, boron trifluoride, boron trifluoride ethyl ether, tri(pentafluorophenyl)boron, triethylboron, camphorsulfonic acid, benzoic acid, salicylic acid, oxalic acid, and malic acid; The inorganic base catalyst is selected from one or more of sodium carbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, lithium hydroxide, magnesium hydroxide, zinc hydroxide, copper hydroxide, iron hydroxide, and ammonium hydroxide; The organic base catalyst is selected from one or more of triethylamine, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and hexamethyldisilazane; The metal chloride catalyst is selected from one or more of ferric chloride, ferric chloride, zinc dichloride, tin chloride, magnesium chloride, titanium chloride, aluminum chloride, and indium chloride; The metal oxide catalyst is selected from one or more of iron oxide, ferroferric oxide, copper oxide, magnesium oxide, zinc oxide, aluminum oxide, calcium oxide, and titanium oxide; The metal salt catalyst is selected from one or more of copper tetrafluoroborate, bismuth trifluoride, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, calcium carbonate, cesium carbonate, sodium glycolate, sodium acetate, lithium diisopropylamide, sodium methoxide, sodium ethoxide, sodium tert-butoxide, potassium tert-butoxide, n-butyl lithium, and isobutyl lithium; The ionic liquid catalyst is selected from one or more of imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium salt ionic liquids, and quaternary phosphonium salt ionic liquids; The Lewis acid-base catalyst is obtained by mixing a Lewis acid and a Lewis base; wherein the Lewis acid is selected from one or more of methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, boron trifluoride, boron trifluoride ethyl ether, tri(pentafluorophenyl)boron, triethylboron, camphorsulfonic acid, benzoic acid, ferric chloride, ferric chloride, zinc dichloride, tin chloride, magnesium chloride, titanium chloride, aluminum chloride, indium chloride, and diethylzinc; and the Lewis base is selected from one or more of triethylamine, ammonia monohydrate, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, hexamethyldisilazane, and carbene; The cation exchange resin is selected from one or more of a strongly acidic styrene-based cation exchange resin, a weakly acidic styrene-propylene-based cation exchange resin, a styrene divinyl benzene resin, and an acrylic acid-based cation exchange resin; The molecular sieve catalyst is selected from one or more of zirconium sulfate molecular sieve, β molecular sieve, LaY molecular sieve, TS-1 molecular sieve, USY molecular sieve, and ZSM-5 molecular sieve.

7. The method according to claim 2, characterized in that: The catalyst is selected from an inorganic acid catalyst, an organic acid catalyst, a metal chloride catalyst, a metal oxide catalyst, a metal salt catalyst, a solid acid catalyst or a Lewis acid-base pair catalyst.

8. The method according to claim 1, characterized in that: The reaction temperature is -50 to 100°C and the reaction time is 10 to 60 minutes.

9. The method according to claim 1, characterized in that: After the reaction is completed, the method further includes the steps of filtering, washing, distilling and crystallizing the crude product obtained by the reaction.

10. A high-purity 1,4-dioxane-2-one, characterized in that: The method according to any one of claims 1 to 9 is used to prepare the present invention.

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