A method for preparing carbonated polyol esters

Abstract

To overcome the problems of difficult reaction equilibrium control, complex production processes, high costs, and low yields in existing technologies, this invention provides a method for preparing polyol carbonate esters, comprising the following steps: mixing and heating a primary alcohol, a carbonate, a secondary alcohol, and a catalyst, stirring until homogeneous, and purifying to obtain the polyol carbonate ester. The primary alcohol contains 3 or more hydroxyl groups, and the secondary alcohol is either a monohydric alcohol or a dihydric alcohol. The method for preparing polyol carbonate esters provided by this invention, by adding a secondary alcohol to regulate the reaction equilibrium, significantly improves the yield. The purified product has high purity, and the production process is simple and low-cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of organic molecule synthesis, and particularly relates to a preparation method of carbonic acid polyol ester. BACKGROUND

[0002] With the wide application of lithium ion batteries in different fields, the market has higher requirements for the performance of lithium ion batteries. Researchers improve the quality of the solid electrolyte interphase (SEI) film by adding different negative electrode film-forming additives containing dioxolane structure (such as vinylene carbonate, fluoroethylene carbonate and vinyl ethylene carbonate) in the electrolyte, thereby improving the cycle life and reversible capacity performance of the battery.

[0003] Therefore, the carbonic acid polyol ester derivative containing the dioxolane structure as a lithium battery additive compound is beneficial to further improve the cycle life and reversible capacity performance of the battery. At present, according to the journal literature Green Chemistry Karolina M., butane tetrol and dimethyl carbonate are reacted under alkaline conditions at 70-90℃ to mainly obtain 2,4,7-trioxa-3-oxo-bicyclo[3.3.0]octane, and the reaction process is as shown in formula 1. Butane tetrol carbonate (4-(1,2-dihydroxyethyl)-1,3-dioxolane-2-ketone) cannot be separated, and the difficulty lies in that the reaction cannot stop at butane tetrol carbonate. The generated butane tetrol carbonate further reacts with dimethyl carbonate to generate 2,4,7-trioxa-3-oxo-bicyclo[3.3.0]octane.

[0004]

[0005] Synthesis of butane tetrol carbonate

[0006] Another method for synthesizing carbonic acid polyol ester derivatives is to use protection / deprotection. The hydroxyl group is first protected by dimethoxy propane, the unprotected hydroxyl group is reacted with the carbonate, and then the product is obtained by deprotection. The reaction process is as shown in formula 2. Although the protection / deprotection method can synthesize various carbonic acid polyol esters, the reaction steps are many, the cost is high, and it is not suitable for industrial large-scale production.

[0007]

[0008] Synthesis of butane tetrol carbonate

[0009] Therefore, it is necessary to develop a carbonic acid polyol ester synthesis method with simple production process, low cost, high yield and recyclable by-products. SUMMARY

[0010] The present application solves the problems of difficult control of reaction equilibrium, complex production process, high cost and low yield in the prior art, and provides a preparation method of carbonic acid polyol ester.

[0011] The technical scheme adopted by the present application to solve the above technical problems is as follows:

[0012] The present application provides a preparation method of carbonic acid polyol ester, comprising the following steps:

[0013] A kind of alcohol, carbonate, a kind of alcohol and catalyst are mixed and heated, and stirred uniformly to obtain a blend comprising carbonic acid polyol ester, the number of hydroxyl groups contained in the first alcohol is greater than or equal to 3, and the number of hydroxyl groups contained in the second alcohol is 1 or 2;

[0014] The blend is purified to obtain carbonic acid polyol ester.

[0015] Optionally, the first alcohol includes one or more of butane tetrol, pentaerythritol, xylitol, sorbitol, mannitol, glucose and inositol;

[0016] Optionally, the carbonate is selected from compounds represented by structural formula I or structural formula II:

[0017]

[0018] wherein R1 and R2 are each independently selected from a hydrocarbon group having 1 to 8 carbon atoms, and R3 is selected from a hydrocarbon group having 1 to 8 carbon atoms.

[0019] Optionally, when the carbonate is selected from the compound represented by structural formula I, the second alcohol is selected from one or more of R1-OH and R2-OH;

[0020] When the carbonate is selected from the compound represented by structural formula II, the second alcohol is selected from HO-H3-OH;

[0021] wherein R1 and R2 are each independently selected from a hydrocarbon group having 1 to 8 carbon atoms, and R3 is selected from a hydrocarbon group having 1 to 8 carbon atoms.

[0022] Optionally, the carbonate includes one or more of methyl ethyl carbonate, diethyl carbonate, ethylene carbonate, dimethyl carbonate and diphenyl carbonate.

[0023] Optionally, the second alcohol includes one or more of methanol, ethanol, ethylene glycol and phenol.

[0024] Optionally, the molar ratio of the first alcohol to the carbonate is 1:1 to 1:10, the molar ratio of the first alcohol to the second alcohol is 1:1 to 1:6, and the mass of the catalyst is 0.1% to 20% of the mass of the first alcohol;

[0025] The heating temperature of the carbonic acid polyol ester is 50°C to 200°C, and the heating time is 1 to 100 hours.

[0026] Optionally, the catalyst comprises one or more of potassium hydroxide, sodium hydroxide, sodium ethoxide, sodium methoxide, potassium carbonate, sodium carbonate, triethylamine and pyridine.

[0027] Optionally, the blend further comprises an aprotic solvent, the aprotic solvent comprising one or more of dioxane, tetrahydrofuran, methylfuran, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide and N-methylpyrrolidone.

[0028] Optionally, the purification comprises one or more of the following a, b, c, d, e steps:

[0029] a. filtration and concentration;

[0030] b. adjusting the pH value to less than or equal to 8, filtration and concentration;

[0031] c. molecular distillation;

[0032] d. column chromatography;

[0033] e. recrystallization.

[0034] The present application obtains polyol carbonate by mixing and heating a type of alcohol, carbonate, a second type of alcohol and a catalyst, and stirring uniformly, and purifying to obtain polyol carbonate, wherein the type of alcohol contains more than or equal to 3 hydroxyl groups, the second type of alcohol is monohydric alcohol or dihydric alcohol, and the addition of the second type of alcohol can control the reaction balance, inhibit the reaction of carbonate and polyol carbonate to generate byproducts, greatly improve the yield, and the production process is simple and low in cost. DETAILED DESCRIPTION

[0035] In order to make the technical problems, technical solutions and beneficial effects of the present application clearer, the present application is further described in detail below in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0036] The present application provides a preparation method of polyol carbonate, comprising the following steps:

[0037] The type of alcohol, carbonate, second type of alcohol and catalyst are mixed and heated, stirred uniformly, to obtain a blend comprising polyol carbonate, the type of alcohol contains more than or equal to 3 hydroxyl groups, and the second type of alcohol contains 1 or 2 hydroxyl groups;

[0038] The blend is purified to obtain polyol carbonate.

[0039] The present application is to mix and heat a kind of alcohol, carbonate, diol and catalyst, stir uniformly, purify to obtain polyol carbonate, wherein the alcohol contains more than or equal to 3 hydroxyl groups, diol is monohydric alcohol or dihydric alcohol, the addition of diol can control the reaction balance, inhibit the reaction of carbonate and polyol carbonate to generate byproducts, so that the yield is greatly improved, and the production process is simple and the cost is low.

[0040] In some specific embodiments, the first alcohol includes one or more of butanetetrol, pentaerythritol, xylitol, sorbitol, mannitol, glucose and inositol.

[0041] In some specific embodiments, the carbonate is selected from compounds represented by structural formula I or structural formula II:

[0042]

[0043] wherein R1 and R2 are each independently selected from a hydrocarbon group having 1-8 carbon atoms, and R3 is selected from a hydrocarbon group having 1-8 carbon atoms.

[0044] In some specific embodiments, when the carbonate is selected from compounds represented by structural formula I, the diol is selected from one or more of R1-OH and R2-OH;

[0045] When the carbonate is selected from compounds represented by structural formula II, the diol is selected from HO-R3-OH;

[0046] wherein R1 and R2 are each independently selected from a hydrocarbon group having 1-8 carbon atoms, and R3 is selected from a hydrocarbon group having 1-8 carbon atoms.

[0047] The addition of diol is to adjust the balance of the reaction, inhibit the generation of byproducts, generate polyol carbonate and improve the yield. When the carbonate and the diol select corresponding R1 group, R2 group and R3 group, the carbonate and the diol generally do not react, even if the reaction occurs, the corresponding carbonate raw material is generated, so that the yield is further improved.

[0048] In some specific embodiments, the diol is selected from alcohols having 1-8 carbon atoms. The diol includes linear or cyclic saturated or unsaturated alcohols having 1-8 carbon atoms.

[0049] In some specific embodiments, the carbonate includes one or more of methyl ethyl carbonate, diethyl carbonate, ethylene carbonate, dimethyl carbonate and diphenyl carbonate.

[0050] In some specific embodiments, the diol includes one or more of methanol, ethanol, ethylene glycol and phenol.

[0051] More preferably, the diol includes one of methanol, ethanol, ethylene glycol and phenol.

[0052] In some specific embodiments, the molar ratio of the first alcohol to the carbonate is 1:1 to 1:10,

[0053] Preferably, the molar ratio of the first alcohol to the carbonate is 1:3 to 1:8.

[0054] More preferably, the molar ratio of the first alcohol to the carbonate is 1:5 to 1:6.

[0055] In some specific embodiments, the molar ratio of the first alcohol to the carbonate is 1:1.5, 1:2, 1:2.5, 1:3.5, 1:4, 1:4.5, 1:5.5, 1:6.5, 1:7, 1:7.5, 1:8.5, 1:9, 1:9.5.

[0056] The molar ratio of the first alcohol to the second alcohol is 1:1 to 1:6.

[0057] Preferably, the molar ratio of the first alcohol to the second alcohol is 1:2 to 1:5.

[0058] More preferably, the molar ratio of the first alcohol to the second alcohol is 1:3 to 1:4.

[0059] In some specific embodiments, the molar ratio of the first alcohol to the second alcohol is 1:1.5, 1:2.5, 1:3.5, 1:4.5, 1:5.5.

[0060] The mass of the catalyst is 0.1% to 20% of the mass of the first alcohol.

[0061] Preferably, the mass of the catalyst is 0.5% to 10% of the mass of the first alcohol.

[0062] More preferably, the mass of the catalyst is 1% to 5% of the mass of the first alcohol.

[0063] In some specific embodiments, the mass of the catalyst is 0.2%, 0.8%, 1.5%, 2%, 3%, 6%, 8%, 12%, 15%, 16%, 18% of the mass of the first alcohol.

[0064] The temperature of the mixing and heating is 50°C to 200°C.

[0065] Preferably, the temperature of the mixing and heating is 60°C to 150°C.

[0066] More preferably, the temperature of the mixing and heating is 70°C to 100°C.

[0067] In some specific embodiments, the temperature of the mixing and heating is 65°C, 75°C, 80°C, 85°C, 90°C, 95°C, 110°C, 120°C, 130°C, 140°C, 160°C, 170°C, 180°C, 190°C.

[0068] The time of the mixed heating is 1-100 hours.

[0069] Preferably, the time of the mixed heating is 5-80 hours.

[0070] More preferably, the time of the mixed heating is 10-60 hours.

[0071] In some specific embodiments, the time of the mixed heating is 8 hours, 12 hours, 15 hours, 18 hours, 20 hours, 22 hours, 25 hours, 28 hours, 30 hours, 32 hours, 35 hours, 40 hours, 45 hours, 50 hours, 55 hours, 65 hours, 75 hours, 85 hours, 90 hours, 95 hours.

[0072] The use of catalysts reduces the temperature of the reaction and accelerates the reaction speed.

[0073] The catalysts include one or more of potassium hydroxide, sodium hydroxide, sodium ethoxide, sodium methoxide, potassium carbonate, sodium carbonate, triethylamine and pyridine.

[0074] In some specific embodiments, the blend further includes an aprotic solvent, and the aprotic solvent includes one or more of dioxane, tetrahydrofuran, methyl furan, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and N-methyl pyrrolidone.

[0075] The aprotic solvent itself is not easy to give a proton, the self-delivery reaction of the proton is weak, and the aprotic solvent has a very strong solubility and a very wide application.

[0076] In some specific embodiments, the purification includes one or more of the following a, b, c, d, e steps:

[0077] a, filtration and concentration;

[0078] b, adjusting the pH value to be less than or equal to 8, filtering and concentrating, preferably, adjusting the pH value to be 5-8, filtering and concentrating;

[0079] c, molecular distillation;

[0080] d, column chromatography;

[0081] e, recrystallization.

[0082] When the reaction of the preparation of the polyol carbonate is continued for a period of time, the solid completely dissolves and disappears, and the solution is clear and transparent. At this time, the reaction needs to be continued, because the second type of alcohol also has a certain solubility to the first type of alcohol, and the complete disappearance of the solid does not mean that the raw materials have completely reacted.

[0083] The present application is further illustrated by the following examples. It should be understood that the present application is not limited to the following examples, and the methods are all conventional methods unless otherwise specified. The materials are all commercially available unless otherwise specified.

[0084] The polyol carbonate shown in the examples is shown in Table 1, but is not limited thereto.

[0085] Table 1

[0086]

[0087]

[0088] Example 1

[0089] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0090] The preparation method thereof includes the following steps:

[0091] (1) In a 3L three-necked flask, add butanetetrol 300g (2.46mol), dimethyl carbonate 663g (7.37mol), methanol 157g (4.92mol), potassium hydroxide 0.14g (2.5mmol), and dioxane 1L, insert a thermometer, set up a condenser water reflux device and a mechanical stirring device. The reaction is carried out at 75°C under mechanical stirring. After about 6 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue heating the reaction for 6 hours.

[0092] (2) Add an equimolar amount of oxalic acid to adjust the pH of the solution to neutral, and filter the salt produced by the neutralization of acid and base. Concentrate the solution at 50°C under reduced pressure to obtain compound 1 crude product 357g in the form of a yellow viscous liquid, the content of compound 1 in the crude product is 85%, and the crude product yield is 83%.

[0093] (3) Mix compound 1 crude product 357g with dimethyl carbonate 1071g, stir thoroughly for half an hour, stand for half an hour, separate the liquid into upper and lower layers, the upper layer is dimethyl carbonate solution, and the lower layer is a small amount of yellow turbid liquid, remove the lower layer liquid by separation. Purify the upper layer dimethyl carbonate solution by column chromatography to obtain compound 1 pure product (purity above 99.9%) 288g in the form of a colorless transparent liquid, with a yield of 79%.

[0094] Example 2

[0095] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0096] The preparation method thereof includes the following steps:

[0097] (1) In a 3L three-necked flask, add xylitol 300g (1.97mol), dimethyl carbonate 533g (5.91mol), methanol 189g (5.91mol), potassium hydroxide 0.22g (4mmol) and solvent dioxane 1L, insert the thermometer, build the condensing water reflux device and mechanical stirring device. The reaction is carried out at 90℃ with mechanical stirring. After about 7 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 7 hours.

[0098] (2) Add an equimolar amount of oxalic acid to adjust the solution pH to neutral, and filter the salt produced by the neutralization of acid and base. The solution is concentrated under reduced pressure at 50℃ to obtain compound 2 crude product 352g, the content of compound 2 in the crude product is 83%, and the crude product yield is 83%.

[0099] (3) Compound 2 crude product is molecularly distilled to obtain compound 2 pure product 290g, colorless transparent liquid, purity 99.5%, yield 82%.

[0100] Example 3

[0101] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0102] The preparation method thereof comprises the following steps:

[0103] (1) In a 3L three-necked flask, add sorbitol 400g (2.20mol), dimethyl carbonate 225g (2.5mol), methanol 35.2g (1.1mol), potassium hydroxide 0.56g (10mmol) and solvent N,N-dimethylformamide 400mL, insert the thermometer, build the condensing water reflux device and mechanical stirring device. The reaction is carried out at 80℃ with mechanical stirring. After about 5 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 5 hours.

[0104] (2) Add an equimolar amount of hydrochloric acid to adjust the solution pH to neutral, and filter the salt produced by the neutralization of acid and base. The solution is concentrated under reduced pressure to obtain compound 3 crude product 433g, the content of compound 3 in the crude product is 88%, and the crude product yield is 83%.

[0105] (3) Compound 3 crude product is recrystallized with ethylene glycol dimethyl ether to obtain compound 3 pure product 360g, colorless transparent crystal, purity 99.8%, yield 78%.

[0106] Example 4

[0107] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0108] The preparation method thereof comprises the following steps:

[0109] (1) In a 3L three-necked flask, add sorbitol 400g (2.20mol), diethyl carbonate 779g (6.6mol), ethanol 204g (4.4mol), sodium methoxide 0.54g (10mmol), insert the thermometer, build the condensing water reflux device and mechanical stirring device. The reaction is carried out at 90℃ under mechanical stirring. After about 5 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 12 hours.

[0110] (2) Add an equimolar amount of oxalic acid to adjust the solution pH to neutral, and filter the salt produced by the neutralization of acid and base. The solution is concentrated under reduced pressure to obtain compound 4 crude product 455g, the content of compound 4 in the crude product is 78%, and the crude product yield is 69%.

[0111] (3) The compound 4 crude product is treated with acetonitrile, and the insoluble impurities in the compound 4 crude product are separated by filtration. Recrystallization with acetonitrile gives compound 4 pure product 331g, colorless transparent crystal, purity 99%, yield 63%.

[0112] Example 5

[0113] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0114] The preparation method thereof comprises the following steps:

[0115] (1) In a 3L three-necked flask, add inositol 396g (2.20mol), dimethyl carbonate 225g (2.5mol), methanol 35.2g (1.1mol), potassium hydroxide 0.56g (10mmol) and solvents dioxane 500mL and N,N-dimethylformamide 200mL, insert the thermometer, build the condensing water reflux device and mechanical stirring device. The reaction is carried out at 80℃ under mechanical stirring. After about 5 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 5 hours.

[0116] (2) Add an equimolar amount of methanesulfonic acid to adjust the solution pH to neutral, and filter the salt produced by the neutralization of acid and base. The solution is concentrated under reduced pressure to obtain compound 5 crude product 441g, the content of compound 5 in the crude product is 84%, and the crude product yield is 82%.

[0117] (3) Recrystallize the compound 5 crude product with ethylene glycol dimethyl ether to obtain compound 5 pure product 356g, colorless transparent crystal, purity 99.4%, yield 77%.

[0118] Example 6

[0119] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0120] The preparation method thereof comprises the following steps:

[0121] (1) In a 3L three-necked flask, add pentaerythritol 340g (2.5mol), methyl ethyl carbonate 520g (5mol), methanol 19.2g (0.6mol), ethanol 27.6g (0.6mol), potassium carbonate 0.27g (2mmol) and solvent dimethyl sulfoxide 1L, insert the thermometer, build the condensation water reflux device and mechanical stirring device. The reaction is mechanically stirred at 80°C. After about 6 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 6 hours.

[0122] (2) Add an equimolar amount of benzenesulfonic acid to adjust the solution pH to neutral, and filter the salt produced by acid-base neutralization. Concentrate the solution at 50°C under reduced pressure to obtain 388g of crude compound 6, with a content of 87% of compound 6 in the crude product, and a crude product yield of 83%.

[0123] (3) Mix 345g of crude compound 6 with 1000g of dimethyl carbonate, and thoroughly stir for half an hour under ultrasonic, stand for half an hour, and separate the lower layer liquid by liquid-liquid separation. Purify the upper dimethyl carbonate solution by column chromatography to obtain 318g of pure compound 6, a colorless transparent liquid, with a purity of 99.2% and a yield of 78%.

[0124] Example 7

[0125] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0126] The preparation method thereof comprises the following steps:

[0127] (1) In a 3L three-necked flask, add sorbitol 400g (2.20mol), dimethyl carbonate 594g (6.6mol), methanol 35.2g (1.1mol), potassium carbonate 0.69g (5mmol) and solvent dioxane 500mL and N,N-dimethylformamide 200mL, insert the thermometer, build the condensation water reflux device and mechanical stirring device. The reaction is mechanically stirred at 90°C. After about 5 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 12 hours.

[0128] (2) Add an equimolar amount of oxalic acid to adjust the solution pH to neutral, and filter the salt produced by acid-base neutralization. Concentrate the solution under reduced pressure to obtain 447g of crude compound 7, with a content of 83% of compound 7 in the crude product, and a crude product yield of 72%.

[0129] (3) Treat the crude compound 7 with acetonitrile, and separate the insoluble impurities in the crude compound 7 by filtration. Recrystallize with acetonitrile to obtain 350g of pure compound 7, a colorless transparent crystal, with a purity of 99.5% and a yield of 68%.

[0130] Example 8

[0131] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0132] The preparation method thereof comprises the following steps:

[0133] (1) In a 3L three-necked flask, add xylitol 300g (1.97mol), dimethyl carbonate 533g (5.91mol), methanol 189g (5.91mol), potassium carbonate 0.27g (2mmol) and solvent dioxane 1L, insert the thermometer, build the condensing water reflux device and mechanical stirring device. The reaction is mechanically stirred at 80°C. After about 8 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 8 hours. The solution is concentrated under reduced pressure at 50°C to obtain 355g of crude compound 8, the content of compound 8 in the crude product is 80%, and the crude product yield is 71%.

[0134] (2) The crude compound 8 is subjected to molecular distillation to obtain 280g of pure compound 8, which is a colorless transparent liquid, the purity is 99.2%, and the yield is 69%.

[0135] Example 9

[0136] This example is used to illustrate the preparation method of the polyol carbonate disclosed in the present application.

[0137] The preparation method thereof comprises the following steps:

[0138] (1) In a 3L three-necked flask, add sorbitol 400g (2.20mol), dimethyl carbonate 594g (6.6mol), methanol 70.4g (2.2mol), potassium carbonate 0.69g (5mmol) and solvent dioxane 500mL and N,N-dimethylformamide 200mL, insert the thermometer, build the condensing water reflux device and mechanical stirring device. The reaction is mechanically stirred at 90°C. After about 5 hours, the solid completely dissolves and disappears, and the solution is clear and transparent. Continue to heat the reaction for 72 hours.

[0139] (2) Add an equimolar amount of oxalic acid to adjust the pH of the solution to neutral, and filter the salt generated by the neutralization of the acid and base. The solution is concentrated under reduced pressure to obtain 461g of crude compound 9, the content of compound 9 in the crude product is 84%, and the crude product yield is 75%.

[0140] (3) The crude compound 9 is treated with acetonitrile, and the insoluble impurities in the crude compound 9 are separated by filtration. The compound 9 is recrystallized with acetonitrile to obtain 378g of pure compound 9, which is a colorless transparent crystal, the purity is 99.1%, and the yield is 72%.

[0141] Comparative Example 1

[0142] The present embodiment is used to illustrate the preparation method of the carbonic polyol ester disclosed in the present application.

[0143] The preparation method thereof comprises the following steps:

[0144] (1) In a 3L three-necked flask, add butanetetrol 300g (2.46mol), dimethyl carbonate 663g (7.37mol), potassium hydroxide 0.14g (2.5mmol) and dioxane 1L, insert a thermometer, set up a condensing water reflux device and a mechanical stirring device. Perform mechanical stirring at 75℃. After about 12 hours, the solid completely dissolves and disappears. Stop the reaction.

[0145] (2) Cool to room temperature, and 120g of white crystals are precipitated. It is detected that the precipitate is butanetetrol. Add an equimolar amount of oxalic acid to the reaction solution to adjust the pH of the solution to neutral, and filter the salt generated by the neutralization of the acid and the base. Concentrate the solution at 50℃ under reduced pressure to obtain 250g of white viscous crude compound 1, and the content of compound 1 in the crude product is 30%, and the yield of the crude product is 21%.

[0146] (3) Mix the 250g of crude compound 1 with dimethyl carbonate 1071g, and purify by column chromatography to obtain 48g of colorless transparent liquid of pure compound 1, the purity is 98%, and the yield is 13%.

[0147] The obtained test results are filled in Table 2.

[0148] Table 2

[0149]

[0150] As can be seen from Table 2, the carbonic polyol ester prepared by the present application has high yield and high purity, and through further purification treatment, the purity reaches more than 99%.

[0151] The above only describes the preferred embodiments of the present application and should not be used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for producing a carbonic polyol ester, characterized by, The method comprises the following steps: a kind of alcohol, carbonate, diol, aprotic solvent and catalyst are mixed and heated, the molar ratio of the alcohol and the carbonate is 1:1~1:10, the molar ratio of the alcohol and the diol is 1:1~1:6, stirring is uniform, a blend including polyol carbonate is obtained, the alcohol includes one or more of butane tetrol, pentaerythritol, xylitol, sorbitol, mannitol and inositol, the diol includes one or more of methanol, ethanol;The carbonate includes one or more of methyl ethyl carbonate, diethyl carbonate, ethylene carbonate, dimethyl carbonate and diphenyl carbonate;The catalyst includes one or more of potassium hydroxide, sodium hydroxide, sodium ethoxide, sodium methoxide, potassium carbonate, sodium carbonate, triethylamine and pyridine;The mass of the catalyst is 0.1%~20% of the mass of the alcohol; The temperature of the mixed heating is 50℃~200℃, and the time of the mixed heating is 1~100 hours; The blend is purified to obtain polyol carbonate.

2. The method for producing a carbonic polyol ester according to claim 1, characterized by, The aprotic solvent includes one or more of dioxane, tetrahydrofuran, methyl furan, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide and N-methyl pyrrolidone.

3. The method for producing a carbonic polyol ester according to claim 1, characterized by, The purification includes one or more of the following a, b, c, d, e steps: a, filtration and concentration; b, adjust the pH value to less than or equal to 8, filter and concentrate; c, molecular distillation; d, column chromatography; e, recrystallization.

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