A method for synthesizing borate derivatives

Abstract

The application relates to the technical field of lithium battery electrolyte additives, and proposes a synthesis method of borate ester derivatives, in which propyl alcohol derivatives are used as raw materials, and are reacted with boron trichloride in dichloromethane to obtain borate ester derivatives; the propyl alcohol derivatives are allyl alcohol, propargyl alcohol or hexafluoroisopropyl alcohol; and the borate ester derivatives are triallyl borate, tripropargyl borate or tri(hexafluoroisopropyl) borate. Through the technical scheme, the problem of low yield of the method for synthesizing borate ester derivatives in the related art is solved.

Description

Technical Field

[0001] This invention relates to the field of lithium battery electrolyte additives, specifically to a method for synthesizing a borate ester derivative. Background Technology

[0002] Boronate derivatives, such as triallyl borate, triargyl borate, and tris(hexafluoroisopropyl) borate, possess high thermal stability and can improve the cycle stability and safety performance of lithium-ion batteries when used as electrolyte additives. Currently, the synthesis of these boronate derivatives mainly involves using propanol derivatives as raw materials, activating the hydroxyl groups of the alcohol with boron reagents to synthesize boronate compounds. This reaction is carried out in aqueous solution with the addition of ferrous chloride catalyst, but the highest yield can only reach 80%. Therefore, exploring synthetic methods for boronate derivatives with high yields is extremely necessary. Summary of the Invention

[0003] This invention proposes a method for synthesizing borate ester derivatives, which solves the problem of low yield in related technologies for synthesizing borate ester derivatives.

[0004] The technical solution of the present invention is as follows: This invention proposes a method for synthesizing borate ester derivatives, which uses propanol derivatives as raw materials and reacts them with boron trichloride in dichloromethane to obtain borate ester derivatives. The propanol derivative is allyl alcohol, propargyl alcohol, or hexafluoroisopropanol, and the borate ester derivative is triallyl borate, triargyl borate, or tri(hexafluoroisopropyl) borate.

[0005] As a further technical solution, the molar ratio of the propanol derivative to boron trichloride is 1:(0.4~0.6).

[0006] As a further technical solution, a catalyst is added to the reaction, which is a mixture of sodium aluminate and ferrous chloride in a mass ratio of 1:1.5~2.5.

[0007] As a further technical solution, the catalyst is a mixture of sodium aluminate and ferrous chloride in a mass ratio of 1:2.

[0008] As a further technical solution, the amount of the catalyst used is 1% to 3% of the mass of the propanol derivative.

[0009] As a further technical solution, the reaction is carried out at -20℃ to -10℃.

[0010] As a further technical solution, the reaction time is 2-4 hours.

[0011] As a further technical solution, in the reaction, the exhaust gas is absorbed with sodium hydroxide solution.

[0012] As a further technical solution, after the reaction is completed, the solvent is removed under reduced pressure to obtain a borate ester derivative.

[0013] The working principle and beneficial effects of this invention are as follows: 1. In this invention, by optimizing the design of the reaction raw materials and reaction solvent, using propanol derivatives and boron trichloride as reaction raw materials and dichloromethane as reaction solvent, the reaction yield is significantly improved, thereby increasing the yield of borate ester derivatives and solving the problem of low yield in the synthesis of borate ester derivatives in related technologies.

[0014] 2. In this invention, a mixture of sodium aluminate and ferrous chloride in a mass ratio of 1:1.5~2.5 is also added as a catalyst, which further improves the reaction yield. Attached Figure Description

[0015] Figure 1 This is the gas chromatogram of triallyl borate in Example 1 of the present invention; Figure 2 The 1H NMR spectrum of triallyl borate in Example 1 of this invention; Figure 3 This is the GC-MS spectrum of triallyl borate in Example 1 of the present invention. Detailed Implementation

[0016] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1 The synthesis of triallyl borate includes the following steps: First, the air in the reactor was purged with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, followed by the addition of allyl alcohol (58.08 g, 1 mol) with stirring. A dichloromethane solution (300 mL) of boron trichloride (46.86 g, 0.4 mol) was slowly added dropwise at -20°C. The exhaust gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -20°C for 4 hours. After removing the solvent under reduced pressure, 168.87 g of triallyl borate was obtained. Gas chromatography analysis showed that... Figure 1 As shown, the purity of triallyl borate is 99.33%, and the calculated yield is 92.15%.

[0018] The proton NMR spectrum of triallyl borate is shown below. Figure 2 As shown, 1HNMR (DMSO, 400MHZ): δ 4.33 (d, J=640HZ, 6H), 5.17 (dd, J1=52.4HZ, J2=17.2HZ, 3H), 5.88~5.97 (m, 6H).

[0019] The GC-MS spectrum of triallyl borate is shown below. Figure 3 As shown.

[0020] Example 2 The synthesis of triallyl borate includes the following steps: First, the air in the reactor was replaced with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, and allyl alcohol (58.08 g, 1 mol) was added with stirring. A dichloromethane solution (300 mL) of boron trichloride (70.29 g, 0.6 mol) was slowly added dropwise at -10 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -10 °C for 2 h. After removing the solvent under reduced pressure, 170.6 g of triallyl borate was obtained with a purity of 99.56% and a yield of 93.07%.

[0021] Example 3 The synthesis of triallyl borate includes the following steps: First, the air in the reactor was purged with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, followed by the addition of allyl alcohol (58.08 g, 1 mol), 0.7 g of sodium aluminate, and 1.04 g of ferrous chloride under stirring. A dichloromethane solution (300 mL) of boron trichloride (46.86 g, 0.4 mol) was slowly added dropwise at -20 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -20 °C for 3 h. After removing the solvent under reduced pressure, 175.52 g of triallyl borate was obtained with a purity of 99.03% and a yield of 95.48%.

[0022] Example 4 The synthesis of triallyl borate includes the following steps: First, the air in the reactor was purged with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, followed by the addition of allyl alcohol (58.08 g, 1 mol), 0.17 g of sodium aluminate, and 0.41 g of ferrous chloride under stirring. A dichloromethane solution (300 mL) of boron trichloride (46.86 g, 0.4 mol) was slowly added dropwise at -20 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -20 °C for 3 h. After removing the solvent under reduced pressure, 174.57 g of triallyl borate was obtained with a purity of 99.11% and a yield of 95.05%.

[0023] Example 5 The synthesis of triallyl borate includes the following steps: First, the air in the reactor was purged with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, followed by the addition of allyl alcohol (58.08 g, 1 mol), 0.19 g of sodium aluminate, and 0.38 g of ferrous chloride under stirring. A dichloromethane solution (300 mL) of boron trichloride (46.86 g, 0.4 mol) was slowly added dropwise at -20 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -20 °C for 3 h. After removing the solvent under reduced pressure, 177.75 g of triallyl borate was obtained with a purity of 99.15% and a yield of 96.82%.

[0024] Example 6 The synthesis of triallyl borate includes the following steps: First, the air in the reactor was purged with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, followed by the addition of allyl alcohol (58.08 g, 1 mol) and 0.58 g of ferrous chloride under stirring. A dichloromethane solution (300 mL) of boron trichloride (46.86 g, 0.4 mol) was slowly added dropwise at -20 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -20 °C for 3 h. After removing the solvent under reduced pressure, 172.95 g of triallyl borate was obtained with a purity of 99.07% and a yield of 94.13%.

[0025] The reaction formulas for Examples 1-6 are as follows: Example 7 The synthesis of triarginyl borate includes the following steps: First, the air in the reactor was replaced with nitrogen. Then, 500 mL of dichloromethane was added to the reactor, and propargyl alcohol (56.06 g, 1 mol) was added with stirring. A dichloromethane solution (300 mL) of boron trichloride (58.58 g, 0.5 mol) was slowly added dropwise at -20 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -20 °C for 2 h. After removing the solvent under reduced pressure, 168.60 g of triargyl borate was obtained with a purity of 99.61% and a yield of 92.84%.

[0026] The reaction formula is as follows: Example 8 The synthesis of tris(hexafluoroisopropyl) borate includes the following steps: First, the air in the reactor was replaced with nitrogen. Then, 800 mL of dichloromethane was added to the reactor, and hexafluoroisopropanol (168.04 g, 1 mol) was added with stirring. A dichloromethane solution (300 mL) of boron trichloride (58.58 g, 0.5 mol) was slowly added dropwise at -10 °C. The tail gas was absorbed by sodium hydroxide solution. After the addition was complete, the reaction was carried out at -10 °C for 2 h. After removing the solvent under reduced pressure, 478.52 g of tris(hexafluoroisopropyl) borate was obtained with a purity of 99.35% and a yield of 92.29%.

[0027] The reaction formula is as follows: The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for synthesizing a borate ester derivative, characterized in that, Using propanol derivatives as raw materials, boron trichloride was reacted with boron trichloride in dichloromethane to obtain boron ester derivatives; The propanol derivative is allyl alcohol, propargyl alcohol, or hexafluoroisopropanol, and the borate ester derivative is triallyl borate, triargyl borate, or tris(hexafluoroisopropyl) borate. The molar ratio of the propanol derivative to boron trichloride is 1:(0.4~0.6). The reaction also incorporates a catalyst, which is a mixture of sodium aluminate and ferrous chloride in a mass ratio of 1:2; The amount of catalyst used is 1% to 3% of the mass of the propanol derivative; The reaction is carried out at -20℃ to -10℃ for 2 to 4 hours.

2. The method for synthesizing a borate ester derivative according to claim 1, characterized in that, In the reaction, the exhaust gas is absorbed with sodium hydroxide solution.

3. The method for synthesizing a borate ester derivative according to claim 1, characterized in that, After the reaction is complete, the solvent is removed under reduced pressure to obtain the borate ester derivative.

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