1,2,3-tris(cyanoethyloxy)propane and a method for its preparation
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 江苏瀚康电子材料有限公司
- Filing Date
- 2026-03-13
- Publication Date
- 2026-06-16
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Abstract
Description
Technical Field
[0001] This invention relates to the field of compound synthesis technology, specifically to a method for preparing 1,2,3-tris(cyanoethoxy)propane. Background Technology
[0002] Lithium-ion batteries, with their advantages of high energy density, long cycle life, and low environmental pollution, have been widely used in various fields such as new energy vehicles, portable electronic devices, and energy storage systems. Among these components, the electrolyte, as the "blood" of the lithium-ion battery, plays a crucial role in ion transport, and its performance directly determines key indicators such as cycle life, charge / discharge efficiency, high-temperature stability, and safety. Electrolyte additives, as an important component of the electrolyte, can significantly improve the physicochemical properties of the electrolyte and the electrode / electrolyte interface characteristics, thereby optimizing the overall performance of the lithium-ion battery and making them one of the key materials for enhancing lithium-ion battery performance.
[0003] Among numerous electrolyte additives, nitrile additives, due to their wide electrochemical window, high dielectric constant, and excellent electrochemical stability, are well-suited to the requirements of high-voltage, high-energy-density lithium batteries, demonstrating broad application prospects in the field of lithium battery electrolytes. 1,2,3-Tris(cyanoethoxy)propane (glycerotrionitrile), as an important nitrile additive, possesses a unique molecular structure. In lithium battery electrolytes, it can form a uniform, dense, and stable interface film (SEI film) on the electrode surface, effectively inhibiting electrode material corrosion, electrolyte decomposition, and dendrite growth, thereby significantly improving the cycle performance and long-term stability of lithium batteries. Simultaneously, glycerotrionitrile maintains good stability even at high temperatures, effectively improving the high-temperature cycle performance and thermal safety of lithium batteries, thus becoming a popular nitrile electrolyte additive.
[0004] Currently, the mainstream synthesis method for triglycerides involves an addition reaction between glycerol and acrylonitrile under alkaline conditions. For example, European patent EP2505622A and Korean patent KR20150105790A disclose the preparation of triglycerides from glycerol and acrylonitrile under potassium hydroxide catalysis. This method achieves a yield of approximately 92% for triglycerides. However, neither of these patents discloses the purity index of the prepared triglycerides. The purity of electrolyte additives directly affects the performance of lithium batteries; insufficient purity can lead to reduced battery cycle life, accelerated electrode corrosion, and other problems, failing to meet the requirements for lithium battery electrolytes.
[0005] To address the purity issue of triglycerides, Chinese patents CN103562177A and CN114195681A disclose a post-processing technique combining vacuum distillation and toluene extraction to purify the reaction product, achieving a purity of up to 99%. However, due to the high boiling point of triglycerides, purification using vacuum distillation requires stringent process conditions (such as high vacuum and high distillation temperature), increasing energy consumption and equipment costs, and resulting in operational difficulties and low production efficiency. Furthermore, the reaction of glycerol with acrylonitrile to produce triglycerides easily generates side reactions producing nitriles and other impurities. These impurities have similar chemical properties to triglycerides and are difficult to completely remove using conventional extraction methods such as toluene extraction, resulting in limited purification efficiency. Residual nitriles can damage the stable interfacial film on the electrode surface, exacerbating electrolyte decomposition and electrode corrosion, thus adversely affecting the cycle performance and safety of lithium batteries.
[0006] In summary, existing glycerol trinitrile synthesis and purification processes have significant shortcomings, failing to efficiently and cost-effectively prepare high-purity glycerol trinitrile that meets the requirements for lithium battery electrolytes. This makes it difficult to meet the current lithium battery industry's demand for high-performance electrolyte additives. Therefore, developing a glycerol trinitrile preparation method that can overcome the aforementioned deficiencies of existing technologies is an urgent technical problem to be solved. Summary of the Invention
[0007] To address the aforementioned technical problems, this invention provides 1,2,3-tris(cyanoethoxy)propane and its preparation method.
[0008] This invention provides a method for preparing 1,2,3-tris(cyanoethoxy)propane, comprising the following steps:
[0009] S1 3-chloropropionitrile was added dropwise to sodium glycerol to react and obtain a 1,2,3-tris(cyanoethoxy)propane synthesis solution;
[0010] S2 purifies the 1,2,3-tris(cyanoethoxy)propane synthesis solution to obtain the 1,2,3-tris(cyanoethoxy)propane product.
[0011] This invention abandons the traditional method of reacting glycerol with acrylonitrile, and instead uses sodium glycerol and 3-chloropropionitrile as reaction raw materials to synthesize 1,2,3-tris(cyanoethoxy)propane through the following nucleophilic substitution reaction, and then combines it with purification process to obtain high-purity 1,2,3-tris(cyanoethoxy)propane.
[0012]
[0013] By replacing glycerol with sodium glycerol as the reaction substrate, the hydroxyl hydrogen is replaced by sodium, significantly enhancing nucleophilicity and enabling a highly efficient nucleophilic substitution reaction with 3-chloropropionitrile, greatly improving reaction selectivity. Simultaneously, replacing acrylonitrile with 3-chloropropionitrile results in greater chemical stability, reducing the likelihood of polymerization and self-addition side reactions, thus minimizing the formation of harmful impurities such as nitriles at the reaction source and effectively improving the purity of the crude product. The only byproduct of this reaction is sodium chloride. Compared to the polymerization impurities and nitrile impurities that may be generated in conventional processes, sodium chloride is non-toxic, non-corrosive, and readily soluble in water, allowing for separation and recovery through simple washing and filtration. The recovered sodium chloride can be recycled as a chemical raw material, realizing the resource utilization of byproducts and fundamentally solving the problems of difficult byproduct treatment and environmental pollution in existing technologies. This invention's preparation method not only has fewer side reactions, green byproducts, and high purification efficiency, but also offers certain economic benefits.
[0014] Further, in step S1, the molar ratio of sodium glycerol to 3-chloropropionitrile is 1:(3.0~3.7); specifically, the molar ratio of sodium glycerol to 3-chloropropionitrile is a range of 1:3.0, 1:3.1, 1:3.2, 1:3.3, 1:3.4, 1:3.5, 1:3.6, 1:3.7 or any combination thereof; preferably, the molar ratio of sodium glycerol to 3-chloropropionitrile is 1:(3.0~3.2).
[0015] Further, in step S1, the reaction temperature for adding 3-chloropropionitrile dropwise to sodium glycerol is 30~60℃, the dropwise addition time is 2.0~5.0h, and after the dropwise addition is completed, the mixture is kept at this temperature for 1~4h. Specifically, the reaction temperature is a range of 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, 60℃, or any combination thereof; preferably, the reaction temperature is 40~50℃. The dropwise addition time of 3-chloropropionitrile is 2.0h, 2.5h, 3.0h, 3.5h, 4.0h, 4.5h, 5.0h, or any combination thereof; preferably, the dropwise addition time is 3.0~4.0h. The heat preservation time is a range of 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h or any combination thereof; preferably, the heat preservation time is 2~3h.
[0016] Furthermore, in step S1, sodium glycerol is prepared by reacting glycerol with metallic sodium. This reaction is carried out under ventilated conditions.
[0017]
[0018] Further, the molar ratio of glycerol to sodium is 1:(3.0~3.5); specifically, the molar ratio of glycerol to sodium is 1:3.0, 1:3.1, 1:3.2, 1:3.3, 1:3.4, or 1:3.5; preferably, the molar ratio of glycerol to sodium is 1:(3.0~3.1).
[0019] Furthermore, the reaction time of glycerol with sodium is 2-5 hours; specifically, the reaction time of glycerol with sodium is 2.0 hours, 2.5 hours, 3.0 hours, 3.5 hours, 4.0 hours, 4.5 hours, or 5.0 hours; preferably, the reaction time of glycerol with sodium is 3-4 hours.
[0020] Furthermore, metallic sodium is added to glycerol in portions, and the reaction ends when no more bubbles are produced. Excess sodium is then filtered off to obtain sodium glycerol.
[0021] Furthermore, the purification of the 1,2,3-tris(cyanoethoxy)propane synthesis solution in step S2 includes:
[0022] S21 Add solvent to dilute the 1,2,3-tris(cyanoethoxy)propane synthesis solution;
[0023] S22 After washing and extracting the diluted 1,2,3-tris(cyanoethoxy)propane synthesis solution with water, the organic phase of 1,2,3-tris(cyanoethoxy)propane was obtained;
[0024] S23 The organic phase of 1,2,3-tris(cyanoethoxy)propane was subjected to vacuum distillation to remove the solvent and 3-chloropropionitrile, yielding crude 1,2,3-tris(cyanoethoxy)propane.
[0025] S24 Add solvent to dilute crude 1,2,3-tris(cyanoethoxy)propane, then add activated carbon for adsorption and decolorization. After decolorization, remove the activated carbon to obtain a decolorized 1,2,3-tris(cyanoethoxy)propane solution.
[0026] S25 was used to decolorize a 1,2,3-tris(cyanoethoxy)propane solution under reduced pressure to obtain the 1,2,3-tris(cyanoethoxy)propane product.
[0027] Further, in step S21, the mass ratio of the solvent used for dilution to the 1,2,3-tris(cyanoethoxy)propane synthesis solution is (1.2~2.0):1. Specifically, the mass ratio of the solvent to the 1,2,3-tris(cyanoethoxy)propane synthesis solution is 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2.0:1, or any combination thereof; preferably, the mass ratio of the solvent to the 1,2,3-tris(cyanoethoxy)propane synthesis solution is (1.3~1.5):1.
[0028] Further, in step S22, the mass ratio of water used for washing extraction to solvent used for dilution is (1.2~3.0):1, and the washing is performed multiple times. Specifically, the mass ratio of water used for washing extraction to solvent used for dilution is 1.2:1, 1.3:1, 1.4:1, 1.6:1, 1.8:1, 2:1, 2.2:1, 2.4:1, 2.5:1, 2.6:1, 2.8:1, 3.0:1, or any combination thereof; preferably, the mass ratio of water used for washing extraction to solvent used for dilution is 1:(1.4~2.0), and pure water is used for washing, with the organic phase being extracted through 4~6 washes. It should be noted that 1,2,3-tris(cyanoethoxy)propane is soluble in water, therefore, the 1,2,3-tris(cyanoethoxy)propane synthesis solution needs to be diluted with an organic solvent before water extraction. This invention employs water washing to extract the organic phase. Through multiple standard liquid-liquid extraction operations, water-soluble impurities such as salts, unreacted cyanide, and polar byproducts can be removed from the organic phase. Traditional purification processes often use a combination of toluene extraction and vacuum distillation, which is based on the existing method of catalytically synthesizing triglycerides from glycerol and acrylonitrile under alkaline conditions. Because acrylonitrile has double bonds, it is prone to self-polymerization under alkaline conditions or reacts with trace amounts of water to form 2-cyanoethyl ether. These self-polymerized impurities and 2-cyanoethyl ether have similar polarities to triglycerides and are difficult to remove by water washing alone, requiring further extraction and purification with organic solvents. Furthermore, these impurities have high boiling points and are difficult to remove by conventional vacuum distillation, resulting in a complex and costly purification process. In contrast, the main byproduct generated in the reaction system of this invention is sodium chloride, which can be removed by simple aqueous phase extraction combined with conventional vacuum distillation. Therefore, the purification process is simpler, the production cost is lower, and organic wastewater discharge is reduced, making it highly compatible with the reaction system of this invention.
[0029] Furthermore, in step S23, the vacuum distillation specifically involves performing vacuum distillation on the 1,2,3-tris(cyanoethoxy)propane organic phase at a temperature of 90~120℃ and a pressure of -0.099~-0.096 MPa, with the distillation endpoint being less than 50 ppm of 3-chloropropionitrile in the 1,2,3-tris(cyanoethoxy)propane. This process is used to remove the solvent and excess 3-chloropropionitrile, yielding crude 1,2,3-tris(cyanoethoxy)propane.
[0030] Preferably, the vacuum distillation temperature is 95~110℃.
[0031] Furthermore, after vacuum distillation and heating to above 80°C, the crude 1,2,3-tris(cyanoethoxy)propane will darken in color, requiring decolorization. Specifically, the decolorization involves solvent dilution of the crude 1,2,3-tris(cyanoethoxy)propane at a mass ratio of 1:(1.1~1.5), followed by adsorption and decolorization with activated carbon at a concentration of 1~2% of the solvent mass. The decolorization time is 2~3 hours. After decolorization, the activated carbon is filtered off to obtain a decolorized 1,2,3-tris(cyanoethoxy)propane solution.
[0032] Furthermore, the decolorized 1,2,3-tris(cyanoethoxy)propane solution was subjected to desolventizing under reduced pressure at a temperature of 40~70℃ and a pressure of -0.099~-0.096 MPa. The distillation endpoint was set at a solvent content of less than 1000 ppm in the 1,2,3-tris(cyanoethoxy)propane, yielding the final product of 1,2,3-tris(cyanoethoxy)propane.
[0033] Preferably, the desolventizing temperature is 50~60℃.
[0034] Furthermore, the solvent is selected from at least one of dichloromethane, methyl tert-butyl ether, dimethyl carbonate, and ethyl methyl carbonate.
[0035] A second aspect of the present invention provides 1,2,3-tris(cyanoethoxy)propane, which is prepared by the above-described method for preparing 1,2,3-tris(cyanoethoxy)propane.
[0036] Compared with the prior art, the present invention has the following beneficial effects:
[0037] This invention prepares 1,2,3-tris(cyanoethoxy)propane (glycerol trinitrile) via a Williamson synthesis reaction involving a nucleophilic substitution reaction of sodium glycerol with 3-chloropropionitrile. Compared to the traditional route for preparing glycerol trinitrile from glycerol and acrylonitrile, this invention uses 3-chloropropionitrile instead of acrylonitrile, resulting in a more stable raw material structure and avoiding side reactions such as self-polymerization of acrylonitrile under alkaline conditions and the formation of 2-cyanoethyl ether from trace amounts of water, thus reducing impurity generation at the source. In existing technologies, self-polymerization impurities and 2-cyanoethyl ether have similar polarities to the product, making them difficult to remove through extraction and washing, and their high boiling points make them difficult to separate using ordinary vacuum distillation. This invention produces almost none of these difficult-to-remove impurities, significantly reducing purification difficulty and improving purification efficiency. This method not only solves the purification problem of glycerol trinitrile, reduces production costs, and decreases the discharge of organic wastewater, but also yields high-purity 1,2,3-tris(cyanoethoxy)propane, improving economic efficiency to a certain extent. Detailed Implementation
[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.
[0039] Raw material description in the examples:
[0040] Glycerol, analytical grade, provided by Shanghai Aladdin Biochemical Technology Co., Ltd.
[0041] 3-Chloropropionitrile, GC≥98.0%, provided by Shanghai Aladdin Biochemical Technology Co., Ltd.
[0042] Sodium metal, GC≥99.7%, provided by Shanghai Aladdin Biochemical Technology Co., Ltd.
[0043] Activated carbon, provided by Jiangsu Enkai Activated Carbon Co., Ltd.
[0044] Dichloromethane, analytical grade, provided by Sinopharm Chemical Reagent Co., Ltd.
[0045] Example 1
[0046] The method for preparing 1,2,3-tris(cyanoethoxy)propane in this embodiment includes the following steps:
[0047] S1 Preparation of sodium glycerol: Add 46 g of glycerol to a three-necked flask with an exhaust flask attached to the end. Take 34.5 g of metallic sodium and add it to the three-necked flask in 10 portions. Stir slowly until no solid metallic sodium is observed in the flask and no large amount of bubbles are discharged from the exhaust flask. Then continue to add metallic sodium. The reaction time is 3 hours to obtain sodium glycerol. The reaction should be carried out under good ventilation.
[0048] Preparation of 1,2,3-tris(cyanoethoxy)propane organic phase S2: Take 79.2g of sodium glycerol and heat to the reaction temperature of 50℃. Take 134.6g of 3-chloropropionitrile and add it dropwise over 3 hours. After the addition is complete, keep warm for 2 hours. The reaction solution changes from colorless to a pale yellow viscous liquid. Add 277.9g of dichloromethane to dilute the reaction solution and stir until completely dissolved. Weigh 389.1g of pure water and wash the organic phase five times to remove salt. The water washing process can remove the color of the organic phase, changing it from pale yellow to a colorless solution. After washing, 125.9g of 1,2,3-tris(cyanoethoxy)propane organic phase remains.
[0049] S3 Purification: The 1,2,3-tris(cyanoethoxy)propane synthesis solution was subjected to vacuum distillation to remove the solvent and unreacted 3-chloropropionitrile. The distillation temperature was 95℃, the pressure was -0.099MPa, and the vacuum distillation time was 3 hours. The remaining bottom liquid (crude 1,2,3-tris(cyanoethoxy)propane) was 113.3g. Gas phase analysis of the bottom liquid showed that the main content of 1,2,3-tris(cyanoethoxy)propane was 99.52%, and the content of 3-chloropropionitrile was 20%. During the high-temperature concentration process, 1,2,3-tris(cyanoethoxy)propane undergoes a color change, transforming from a colorless solution to a yellow viscous liquid. Adding 136.0 g of dichloromethane dilutes the bottom liquid, which becomes pale yellow. Adding 2.6 g of activated carbon decolorizes and adsorbs for 2.5 h. After decolorization, filtering removes the activated carbon, resulting in a colorless solution. The solution is then concentrated under reduced pressure to remove dichloromethane. The concentration temperature is 50℃, the pressure is -0.099 MPa, and the concentration time is 2 h. After concentration, 109 g of 1,2,3-tris(cyanoethoxy)propane is obtained as a pale yellow viscous liquid. Gas phase analysis shows that the main content of 1,2,3-tris(cyanoethoxy)propane is 99.52%, and the dichloromethane content is 329 ppm, with a yield of 96.2%.
[0050] Examples 2-14
[0051] Examples 2-14 describe the preparation methods for 1,2,3-tris(cyanoethoxy)propane, which include most of the operational steps in Example 1 above. The differences lie in the following parameters: the molar ratio of sodium glycerol to 3-chloropropionitrile, the dropping time of 3-chloropropionitrile, the reaction temperature of sodium glycerol and 3-chloropropionitrile, the aging time after the sodium glycerol is added, the mass ratio of solvent to 1,2,3-tris(cyanoethoxy)propane synthesis solution, the mass ratio of solvent to pure water, the vacuum distillation conditions, and the decolorization conditions. These parameters are detailed in Table 1 below.
[0052] Table 1
[0053] project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Molar ratio of glycerol to metallic sodium 1:3.0 1:3.0 1:3.3 1:3.1 1:3.5 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 01:03.0 Reaction time of glycerol with sodium (h) 3 2 3.5 4 5 3 3 3 3 3 3 3 3 3 Molar ratio of sodium glycerol to 3-chloropropionitrile 1:3.0 1:3.4 1:3.1 1:3.7 1:3.2 1:2.9 1:3.8 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 1:3.0 3-Chloropropionitrile addition time (h) 3 3.5 2 5 4 3 3 1.8 3 3 3 3 3 3 Reaction temperature of sodium glycerol with 3-chloropropionitrile (°C) 40 30 45 60 50 50 40 40 27 63 40 40 40 40 After sodium glycerol is added, the incubation and maturation time (h) is as follows. 2 1 2.5 4 3 2 2 2 2 2 0.8 2 2 2 Solvent to 1,2,3-tris(cyanoethoxy)propane synthesis solution mass ratio 1.3:1 1.2:1 1.5:1 1.4:1 2.0:1 1.3:1 1.3:1 1.3:1 1.3:1 1.3:1 1.3:1 1.3:1 1.1:1 2.1:1 Pure water to solvent mass ratio 1.4:1 1.7:1 1.2:1 2.0:1 3.0:1 1.4:1 1.4:1 1.4:1 1.4:1 1.4:1 1.4:1 1.4:1 1.4:1 1.4:1 Vacuum distillation temperature (°C) 95 120 102 90 110 105 95 95 95 95 95 95 95 95 Reduced pressure distillation (MPa) -0.099 -0.099 -0.096 -0.098 -0.099 -0.099 -0.099 -0.099 -0.099 -0.099 -0.099 -0.099 -0.099 -0.099 Before decolorization, the mass ratio of crude 1,2,3-tris(cyanoethoxy)propane to solvent is... 1:1.2 1:1.5 1:1.3 1:1.4 1:1.1 1:1.224 1:1.2 1:1.2 1:1.2 1:1.2 1:1.2 / 1:1.2 1:1.2 Percentage of activated carbon used (%) 1.2 1.8 1.5 1 2 1 1.2 1.2 1.2 1.2 1.2 / 1.2 1.2 Decolorization time (h) 2.5 3 2.5 2 3 2 2.5 2.5 2.5 2.5 2.5 / 2.5 2.5 Reduced pressure solvent removal temperature (°C) 50 55 60 40 70 60 50 50 50 50 50 / 50 50 Decompression desolvation pressure (MPa) -0.099 -0.099 -0.098 -0.099 -0.096 -0.099 -0.099 -0.099 -0.099 -0.099 -0.099 / -0.099 -0.099
[0054] Comparative Example 1
[0055] At room temperature, 46 g (0.5 mol) of glycerol and 0.5 g (0.0125 mol) of sodium hydroxide were added to a 500 mL three-necked flask. The mixture was heated to 60 °C and stirred for 2 h until completely dissolved. The mixture was cooled to 20–25 °C, and 26.5 g (0.5 mol) of acrylonitrile was added dropwise. After the addition was complete, the two phases of the reaction system became immiscible. The mixture was stirred for 2 h until the reaction system became homogeneous (with a temperature rise of approximately 10 °C). The remaining 63.6 g (1.2 mol) of acrylonitrile was slowly added dropwise (controlling the internal temperature to not exceed 30 °C), completing the addition in about 2 h. The reaction was then continued for 5 h. After the reaction was complete, the mixture was dissolved in 300 mL of dichloromethane, washed three times with 200 mL of distilled water until the aqueous phase was neutral, dried with magnesium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain 122 g of a yellow viscous liquid. The crude 1,2,3-tris(cyanoethoxy)propane had a purity of 95.2%.
[0056] Crude 1,2,3-tris(cyanoethoxy)propane was subjected to vacuum distillation to remove solvent, unreacted acrylonitrile, and nitrile impurities. The distillation temperature was 220℃, the pressure was -0.099 MPa, and the vacuum time was 3 h. 140 g of dichloromethane was added to dilute the bottom liquid of the distillation column, and 2.6 g of activated carbon was added for decolorization and adsorption for 2 h. After decolorization, the activated carbon was removed by filtration, and the solution was colorless. Dichloromethane was removed by vacuum concentration at 60℃ and -0.099 MPa for 2 h. 114 g of 1,2,3-tris(cyanoethoxy)propane was obtained after concentration. It was a light yellow viscous liquid. A sample was taken for gas phase analysis. The main content of 1,2,3-tris(cyanoethoxy)propane was 98.1%, dichloromethane was 20 ppm, the yield was 89.1%, and nitrile impurities were 1.2%.
[0057] Comparative Example 2
[0058] At room temperature, 46 g (0.5 mol) of glycerol and 0.5 g (0.0125 mol) of sodium hydroxide were added to a 500 mL three-necked flask. The mixture was heated to 60 °C and stirred for 2 h until completely dissolved. The mixture was cooled to 20–25 °C, and 26.5 g (0.5 mol) of acrylonitrile was added dropwise. After the addition was complete, the two phases of the reaction system became immiscible. The mixture was stirred for 2 h until the reaction system became homogeneous (with a temperature rise of approximately 10 °C). The remaining 63.6 g (1.2 mol) of acrylonitrile was slowly added dropwise (controlling the internal temperature to not exceed 30 °C), completing the addition in about 2 h. The reaction was then continued for 5 h. After the reaction was complete, the mixture was dissolved in 300 mL of dichloromethane and washed three times with 200 mL of distilled water until the aqueous phase was neutral. The solution was dried with magnesium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain 122 g of a yellow viscous liquid. The crude 1,2,3-tris(cyanoethoxy)propane had a purity of 95.2%.
[0059] The viscous liquid was further extracted twice with 500 mL of toluene. The remaining red residue was discarded. The toluene phases were combined and concentrated under reduced pressure to remove the toluene, yielding 108 g of 1,2,3-tris(cyanoethoxy)propane. The product yield was calculated to be 86%, the GC product purity was 99.6%, and no nitrile impurities were detected by GC-MS.
[0060] The 1,2,3-tris(cyanoethoxy)propane prepared in the examples and comparative examples was tested, and the results are shown in Table 2.
[0061] Table 2
[0062] Group Triglyceride content (%) Product yield (%) Nitrile impurities (%) Example 1 99.52 96.2 Not detected Example 2 99.37 92.2 Not detected Example 3 99.41 93.5 Not detected Example 4 99.40 95.2 Not detected Example 5 99.49 95.9 Not detected Example 6 99.34 90.9 Not detected Example 7 99.41 92.1 Not detected Example 8 99.21 92.2 Not detected Example 9 99.33 91.7 Not detected Example 10 99.19 92.1 Not detected Example 11 99.23 92.0 Not detected Example 12 99.40 93.5 Not detected Example 13 99.42 90.1 Not detected Example 14 99.11 95.8 Not detected Comparative Example 1 98.10 89.1 1.2 Comparative Example 2 99.60 86.0 Not detected
[0063] Note: " / " in the table indicates that the item does not exist.
[0064] The test results of Examples 1-14 and Comparative Examples 1-2 show that the present invention uses sodium glycerol and 3-chloropropionitrile as raw materials to prepare 1,2,3-tris(cyanoethoxy)propane via the Williamson synthesis reaction. The purity and yield of the obtained product are significantly higher than those of the traditional preparation route using glycerol and acrylonitrile as raw materials in the prior art. This fully demonstrates the obvious advantages of the technical solution of the present invention in terms of product quality and synthesis efficiency.
[0065] A comparison of the test results of Examples 1-14 and Comparative Example 2 shows that the present invention, through a simple and mild water extraction purification process, can achieve a purity level of 1,2,3-tris(cyanoethoxy)propane comparable to that of complex and stringent purification processes in the prior art. This significantly simplifies the purification process, reduces the difficulty of process operation, and lowers production costs. This also demonstrates that the 1,2,3-tris(cyanoethoxy)propane preparation method of the present invention is compatible with the above-mentioned simplified purification process, thereby allowing for simplification of the purification process and showcasing the high process applicability of the preparation method of the present invention.
[0066] A comparison of the test results of Examples 1-5 and Examples 6-14 shows that when the reaction conditions of sodium glycerol and 3-chloropropionitrile, as well as the subsequent purification conditions, are controlled within the preferred range of this invention, the occurrence of side reactions can be further suppressed, and the generation of impurities can be reduced, thereby resulting in 1,2,3-tris(cyanoethoxy)propane with higher purity and yield. This indicates that by synergistically optimizing the reaction raw materials, reaction conditions, and purification process, this invention can effectively avoid impurities that are difficult to separate, such as the easy self-polymerization of acrylonitrile and the formation of 2-cyanoethyl ether by single hydrolysis, which are common in traditional processes. This significantly reduces the difficulty of purification, improves purification efficiency, and simultaneously reduces production costs and organic wastewater discharge, ultimately achieving the efficient and stable preparation of high-purity 1,2,3-tris(cyanoethoxy)propane.
[0067] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the nature and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention.
Claims
A method for preparing 1,1,2,3-tris(cyanoethoxy)propane, characterized in that, Includes the following steps: S1 3-chloropropionitrile was added dropwise to sodium glycerol to react and obtain a 1,2,3-tris(cyanoethoxy)propane synthesis solution; S2 purifies the 1,2,3-tris(cyanoethoxy)propane synthesis solution to obtain the 1,2,3-tris(cyanoethoxy)propane product.
2. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 1, characterized in that, In step S1, the molar ratio of sodium glycerol to 3-chloropropionitrile is 1:(3.0~3.7).
3. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 1, characterized in that, In step S1, the reaction temperature for adding 3-chloropropionitrile to sodium glycerol is 30~60℃, the addition time of 3-chloropropionitrile is 2.0~5.0h, and after the addition is completed, the mixture is kept at the temperature for 1~4h for curing.
4. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 1, characterized in that, In step S1, sodium glycerol is prepared by reacting glycerol with sodium metal, wherein the molar ratio of glycerol to sodium metal is 1:(3.0~3.5), and the reaction time of glycerol with sodium metal is 2~5h.
5. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 4, characterized in that, In the preparation of sodium glycerol by reacting glycerol with metallic sodium, metallic sodium is added to glycerol in portions, and the reaction ends when no more bubbles are generated.
6. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to any one of claims 1-5, characterized in that, The purification of the 1,2,3-tris(cyanoethoxy)propane synthesis solution in step S2 includes: S21 Add solvent to dilute the 1,2,3-tris(cyanoethoxy)propane synthesis solution; S22 After washing and extracting the diluted 1,2,3-tris(cyanoethoxy)propane synthesis solution with water, the organic phase of 1,2,3-tris(cyanoethoxy)propane was obtained; S23 The organic phase of 1,2,3-tris(cyanoethoxy)propane was subjected to vacuum distillation to remove the solvent and 3-chloropropionitrile, yielding crude 1,2,3-tris(cyanoethoxy)propane. S24 Add solvent to dilute crude 1,2,3-tris(cyanoethoxy)propane, then add activated carbon for adsorption and decolorization. After decolorization, remove the activated carbon to obtain a decolorized 1,2,3-tris(cyanoethoxy)propane solution. S25 was used to decolorize a 1,2,3-tris(cyanoethoxy)propane solution under reduced pressure to obtain the 1,2,3-tris(cyanoethoxy)propane product.
7. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 6, characterized in that, In step S21, the mass ratio of the solvent to the 1,2,3-tris(cyanoethoxy)propane synthesis solution is (1.2~2.0):1; and / or, In step S22, the water washing extraction uses a water-to-solvent mass ratio of (1.2~3.0):1, and the water washing extraction is performed multiple times; and / or, In step S23, the vacuum distillation temperature is 90~120℃ and the pressure is -0.099~-0.096 MPa; and / or, In step S24, the mass ratio of crude 1,2,3-tris(cyanoethoxy)propane to solvent is 1:(1.1~1.5), and the decolorization time is 2~3 hours; and / or, In step S25, the temperature for descaling is 40~70℃ and the pressure is -0.099~-0.096Mpa.
8. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 6, characterized in that, In step S23, the vacuum distillation ends when the 3-chloropropionitrile content in 1,2,3-tris(cyanoethoxy)propane is less than 50 ppm. In step S25, the solvent removal under reduced pressure is defined as distillation with a solvent content in 1,2,3-tris(cyanoethoxy)propane of less than 1000 ppm as the distillation endpoint.
9. The method for preparing 1,2,3-tris(cyanoethoxy)propane according to claim 6, characterized in that, The solvent is selected from at least one of dichloromethane, methyl tert-butyl ether, dimethyl carbonate, and ethyl methyl carbonate.
10. A 1,2,3-tris(cyanoethoxy)propane, characterized in that, It is prepared by the method for preparing 1,2,3-tris(cyanoethoxy)propane according to any one of claims 1-9.