阅读说明：本技术 一种2,5-二叔丁基对苯二甲醚的制备方法 (Preparation method of 2, 5-di-tert-butyl-p-xylylene ether ) 是由 张晓宇 吴杰 曹青青 钟子坊 周彤 于 2021-02-08 设计创作，主要内容包括：本发明公开了一种2,5-二叔丁基对苯二甲醚的制备方法,包括：(1)在第一催化剂作用下,将叔丁醇与对苯二酚在第一溶剂中进行反应,反应结束后经冷却结晶,过滤,洗涤,烘干,得到2,5-二叔丁基对苯二酚；(2)在第二催化剂作用下,将步骤(1)得到的2,5-二叔丁基对苯二酚与碘甲烷在第二溶剂中进行反应,反应结束后冷却至室温,向反应液中加入卤水和有机溶剂进行萃取,将得到的有机层洗涤,真空干燥,得到2,5-二叔丁基对苯二甲醚产品。本发明具有工艺简单,反应条件温和,绿色环保,成本低,收率高的优点。(The invention discloses a preparation method of 2, 5-di-tert-butyl-p-xylylene ether, which comprises the following steps: (1) under the action of a first catalyst, reacting tert-butyl alcohol with hydroquinone in a first solvent, cooling and crystallizing after the reaction is finished, filtering, washing and drying to obtain 2, 5-di-tert-butylhydroquinone; (2) and (2) under the action of a second catalyst, reacting the 2, 5-di-tert-butyl hydroquinone obtained in the step (1) with methyl iodide in a second solvent, cooling to room temperature after the reaction is finished, adding brine and an organic solvent into the reaction liquid for extraction, washing the obtained organic layer, and drying in vacuum to obtain the 2, 5-di-tert-butyl hydroquinol product. The method has the advantages of simple process, mild reaction conditions, environmental protection, low cost and high yield.)

1. A preparation method of 2, 5-di-tert-butyl-p-xylylene ether is characterized by comprising the following steps:

(1) under the action of a first catalyst, reacting tert-butyl alcohol with hydroquinone in a first solvent, cooling and crystallizing after the reaction is finished, filtering, washing and drying to obtain 2, 5-di-tert-butylhydroquinone;

(2) and (2) under the action of a second catalyst, reacting the 2, 5-di-tert-butyl hydroquinone obtained in the step (1) with methyl iodide in a second solvent, cooling to room temperature after the reaction is finished, adding brine and an organic solvent into the reaction liquid for extraction, washing the obtained organic layer, and drying in vacuum to obtain the 2, 5-di-tert-butyl hydroquinol product.

2. The method for preparing 2, 5-di-tert-butyl-p-dimethylether according to claim 1, characterized in that the first catalyst is one or more of sulfuric acid, hydrochloric acid, nitric acid and acetic acid.

3. The method of claim 1, wherein the first solvent is water.

4. The method for preparing 2, 5-di-tert-butyl-p-dimethylether according to claim 1, characterized in that the second catalyst is one or more of sodium hydride, calcium hydride and potassium hydride.

5. The method for preparing 2, 5-di-tert-butyl-p-dimethylether according to claim 1, characterized in that the second solvent is one or more of dichloromethane, chloroform, ethyl acetate, petroleum ether, dimethylformamide, tetrahydrofuran, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate.

6. The method for preparing 2, 5-di-tert-butyl-p-xylylene ether according to claim 1, wherein the brine is a saturated aqueous solution of one or more of sodium chloride, potassium chloride, calcium chloride, magnesium chloride, sodium bromide, potassium bromide, calcium bromide and magnesium bromide.

7. The method for preparing 2, 5-di-tert-butyl hydroquinol according to claim 1, wherein the molar ratio of 2, 5-di-tert-butyl hydroquinone to tert-butyl alcohol is 1: 2-10, wherein the dosage of the first catalyst is 0.1-5% of the mass of tert-butyl alcohol, and the mass ratio of tert-butyl alcohol to the first solvent is 2-6: 1.

8. the preparation method of 2, 5-di-tert-butyl hydroquinol according to claim 1, wherein the molar ratio of 2, 5-di-tert-butyl hydroquinone to iodomethane is 125-500: 1, the amount of the second catalyst is 0.5-30% of the molar number of 2, 5-di-tert-butyl hydroquinone, and the mass ratio of 2, 5-di-tert-butyl hydroquinone to the second solvent is 1: 2-20, wherein the mass ratio of the brine to the 2, 5-di-tert-butylhydroquinone is (4-6): 1, the mass ratio of the organic solvent to the brine is 1: 1 to 10.

9. The method for preparing 2, 5-di-tert-butyl-p-dimethylether according to claim 1, characterized in that the temperature of the reaction in the step (1) is 70 to 90 ℃ and the reaction time is 0.1 to 5 hours.

10. The method for preparing 2, 5-di-tert-butyl-p-dimethylether according to claim 1, characterized in that the temperature of the reaction in the step (2) is 30 to 80 ℃ and the reaction time is 0.5 to 2 hours.

Technical Field

The invention relates to the technical field of batteries, in particular to a preparation method of 2, 5-di-tert-butyl-p-xylylene ether.

Background

Lithium ion rechargeable batteries are widely used in portable electronic products and vehicles due to their advantages of large specific capacity, high energy density, long shelf life, no memory effect, etc. However, currently, safety issues associated with lithium ion batteries limit their use in many areas, such as power grids and electric vehicle applications. Among these problems, a serious problem is caused by a series of consequences caused by overcharge.

To prevent such overcharging, commercial lithium ion batteries are often equipped with external electronics protection, which increases the complexity, volume, and cost of the system. One effective cost reduction approach is to add so-called redox shuttle additives directly to the electrolyte to provide inherent chemical protection. These additives are electrochemically reversible molecules that are inactive during normal charging of the battery, but that oxidize when the potential is increased above the charge termination potential of the cathode material. An electrochemical self-protection mechanism for preventing overcharge and overdischarge is established in the battery, and in the process of playing a protection role, the battery system cannot be damaged irreversibly, so that the aim of protecting the battery is fulfilled.

In the last decade, efforts have been made to develop redox shuttle molecules suitable for overcharge protection of lithium ion batteries, and a series of compounds such as lithium ferrocene, 2,6, 6-Tetramethylpiperidinyloxy (TEMPO), phenothiazine, etc. have been developed in succession. Although some of these compounds exhibit significant chemical and electrochemical stability, their redox potentials are for commercially used LiFePO₄The cathode is insufficient, compared to Li/Li⁺，LiFePO₄The cathode was operated at 3.5V. Generally, the redox potential of the redox shuttle molecule should be at least 0.3V higher than the charge termination potential to minimize interference with the normal charging of the cell and thereby avoid self-discharge.

The alkoxy benzene derivatives attract attention due to higher oxidation-reduction potential and adjustable physical and electrochemical properties. There are reports of 2, 5-di-tert-butyl-p-xylylene ether (DDB) vs. Li/Li⁺Has an oxidation-reduction potential of 3.9V, and can be LiFePO₄The cathode provides good overcharge protection. Several theories have been proposed to explain this superior characteristic.Specifically, the combination of two large tertiary butyl groups at the 2,5 positions on the 1, 4-dimethoxybenzene ring is believed to protect the electrochemically generated radical cations from undesirable side reactions such as disproportionation, radical addition, and cross-recombination. Thus, the redox shuttle additive itself can be effectively prevented from failing, thereby providing overcharge protection to the battery for an extremely long period of time. The molecular structure of 2, 5-di-tert-butyl-p-xylylene ether (DDB) is as follows:

DDB is an important electrolyte additive that is effective in preventing overcharge of the battery, and thus is in great demand. At present, 2, 5-di-tert-butyl-p-dimethyl ether is generally synthesized by taking p-dimethyl ether and tert-butyl alcohol as raw materials, glacial acetic acid as a solvent and sulfuric acid as a catalyst, a product system after reaction is filtered to remove the glacial acetic acid, the sulfuric acid, water and unreacted tert-butyl alcohol, then is recrystallized in ethanol, and a refined product is filtered and dried to obtain the product.

For example, Chinese patent publication No. CN211886843U discloses a reactor for efficiently preparing 2, 5-di-tert-butyl-p-xylylene ether. The reactor has the functions of reaction, filtration and recrystallization, is used for preparing the 2, 5-di-tert-butyl-p-xylylene ether by taking the p-xylylene ether and the tert-butyl alcohol as raw materials, is convenient to operate, has short production flow, realizes the high-efficiency production of the 2, 5-di-tert-butyl-p-xylylene ether, and has the yield of the 2, 5-di-tert-butyl-p-xylylene ether of more than 85 percent and the purity of more than 99 percent.

For another example, chinese patent publication No. CN108649269A discloses an electrolyte additive for hydrofluoroether-based high-nickel ternary lithium batteries and a preparation method thereof. The preparation process comprises the following steps: (1) adding 2, 5-di-tert-butylhydroquinone, hydrofluoroether olefin, potassium carbonate and isobutanol into a sealed reaction kettle; (2) replacing the gas in the reaction kettle with nitrogen; (3) heating and reacting the reaction kettle and stirring; (4) and (3) carrying out reduced pressure rectification on the reacted mixture to obtain the hydrofluoroether-based functionalized 2, 5-di-tert-butyl hydroquinone.

The prior art has the disadvantages that the production process is inconvenient to operate, the production flow is long, and the cost is high; or low yield, more three wastes, environmental pollution and the like.

Disclosure of Invention

The invention aims to overcome the defects of the background technology and provides the preparation method of the 2, 5-di-tert-butyl-p-xylylene ether, which has the advantages of simple process, mild reaction conditions, environmental protection, low cost and high yield.

In order to achieve the purpose, the invention adopts the technical scheme that: a preparation method of 2, 5-di-tert-butyl-p-xylylene ether comprises the following steps:

(1) under the action of a first catalyst, reacting tert-butyl alcohol with hydroquinone in a first solvent, cooling and crystallizing after the reaction is finished, filtering, washing and drying to obtain 2, 5-di-tert-butylhydroquinone;

(2) and (2) under the action of a second catalyst, reacting the 2, 5-di-tert-butyl hydroquinone obtained in the step (1) with methyl iodide in a second solvent, cooling to room temperature after the reaction is finished, adding brine and an organic solvent into the reaction liquid for extraction, washing the obtained organic layer, and drying in vacuum to obtain the 2, 5-di-tert-butyl hydroquinol product.

Preferably, the first catalyst is one or more of sulfuric acid, hydrochloric acid, nitric acid and acetic acid.

Preferably, the first solvent is water.

Preferably, the second catalyst is one or more of sodium hydride, calcium hydride and potassium hydride.

Preferably, the second solvent is one or more of dichloromethane, chloroform, ethyl acetate, petroleum ether, Dimethylformamide (DMF), Tetrahydrofuran (THF), dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate.

Preferably, the brine is a saturated aqueous solution of one or more of sodium chloride, potassium chloride, calcium chloride, magnesium chloride, sodium bromide, potassium bromide, calcium bromide and magnesium bromide.

Preferably, the molar ratio of hydroquinone to tert-butanol is 1: 2-10, more preferably 1: 3-6; the dosage of the first catalyst is 0.1-5% of the mass of the tertiary butanol, and more preferably 0.2-2%; the mass ratio of the tertiary butanol to the first solvent is 2-6: 1.

preferably, the molar ratio of the 2, 5-di-tert-butylhydroquinone to the iodomethane is 125-500: 1; the dosage of the second catalyst is 0.5-30% of the mole number of the 2, 5-di-tert-butylhydroquinone, and more preferably 6-11%; the mass ratio of the 2, 5-di-tert-butylhydroquinone to the second solvent is 1: 2-20, more preferably 1: 5-10; the mass ratio of the brine to the 2, 5-di-tert-butylhydroquinone is (4-6): 1, more preferably 2 to 5: 1; the mass ratio of the organic solvent to the brine is 1: 1-10, more preferably 1: 3 to 5.

Preferably, the reaction temperature in the step (1) is 70-90 ℃, and the reaction time is 0.1-5 h.

Preferably, the reaction temperature in the step (2) is 30-80 ℃, and the reaction time is 0.5-2 h.

Preferably, the organic solvent in step (2) is one or more of dichloromethane, chloroform, ethyl acetate, petroleum ether, Dimethylformamide (DMF), Tetrahydrofuran (THF), dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate.

The preparation method of the 2, 5-di-tert-butyl hydroquinol firstly synthesizes the 2, 5-di-tert-butyl hydroquinone by the reaction of hydroquinone and tert-butyl alcohol in a first solvent under the action of a first catalyst, and then synthesizes the 2, 5-di-tert-butyl hydroquinol and methyl iodide in a second solvent under the action of a second catalyst. The method has the advantages of simple operation, mild and controllable reaction process, efficient, rapid and environment-friendly reaction and low cost, and is suitable for industrial production.

Compared with the prior art, the invention has the following beneficial effects:

1. the method has the advantages of simple process, fewer reaction steps, mild reaction conditions, low requirement on reaction equipment, convenient operation and obvious simplification of the production process;

2. the reaction efficiency is high, the yield is more than 80 percent, and can reach 91 percent at most;

3. the method has the advantages of environmental protection, low cost, easily available raw materials, recyclable solvent, washing liquid and extraction liquid in the reaction process, pollution reduction, effective production cost reduction and accordance with the development direction of environmental protection.

Drawings

FIG. 1 shows the preparation of 2, 5-di-tert-butyl-p-dimethylether obtained in example 1 of the present invention¹HNMR spectrogram;

FIG. 2 shows the preparation of 2, 5-di-tert-butyl-p-dimethylether obtained in example 1 of the present invention¹³CNMR spectrogram.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples, it being understood that the following description is only for the purpose of explaining the present invention and is not intended to limit the present invention.

Example 1

(1) Preparation of 2, 5-di-tert-butylhydroquinone

Adding 55.0g (0.5mol) of hydroquinone into a three-neck flask, adding 40g of deionized water into the three-neck flask, stirring and heating to 80 ℃, adding 60g (0.81mol) of tert-butyl alcohol, slowly dropwise adding into the three-neck flask until the solid in the flask is completely dissolved, preparing 163g (2.2mol) of tert-butyl alcohol and 10g of sulfuric acid into a mixed solution, slowly dropwise adding into the three-neck flask, maintaining the reaction temperature at 80 ℃, reacting for 3 hours, cooling the system to room temperature after the reaction is finished, filtering, washing the obtained solid with 150ml of water for three times, and drying to obtain 107.9g of 2, 5-di-tert-butylhydroquinone with the yield of 97%.

(2) Preparation of 2, 5-di-tert-butyl-p-xylylene ether

And (2) dissolving 44.5g (0.2mol) of the 2, 5-di-tert-butylhydroquinone prepared in the step (1) in 500g of DMF, adding 0.46g (19mmol) of sodium hydride under the protection of nitrogen, stirring for 15min at room temperature, heating to 40 ℃, slowly adding 50ml (0.8mmol) of methyl iodide dropwise, maintaining the reaction temperature at 40 ℃, reacting for 2h, cooling the system to room temperature, slowly adding 200g of saturated saline solution to terminate the reaction, extracting the obtained mixed solution for three times by using 100g of ethyl acetate, washing the organic layer for three times by using 100ml of clear water, and drying in vacuum to obtain 47g of 2, 5-di-tert-butylhydroquinone, wherein the yield is 94% and the total reaction yield is 91%.

Example 2

(1) Preparation of 2, 5-di-tert-butylhydroquinone:

taking 110.0g (1.0mol) of hydroquinone, adding the hydroquinone into a three-neck flask, adding 80g of deionized water into the three-neck flask, stirring and heating the mixture to 70 ℃, taking 90g (1.2mol) of tert-butyl alcohol, slowly dropwise adding the tert-butyl alcohol into the three-neck flask until the solid in the flask is completely dissolved, taking 244.5g (3.3mol) of tert-butyl alcohol and 4g of hydrochloric acid with the mass percentage concentration of 36.5% to prepare a mixed solution, slowly dropwise adding the mixed solution into the three-neck flask, maintaining the reaction temperature at 70 ℃, reacting for 2 hours, cooling the system to room temperature after the reaction is finished, filtering, washing the obtained solid with 200ml of water for three times, and drying to obtain the 2, 5-di-tert-butylhydroquinone (200g, the yield is 90.

(2) Preparation of 2, 5-di-tert-butyl-p-xylylene ether:

dissolving 89g (0.4mol) of 2, 5-di-tert-butyl hydroquinone prepared in the step (1) in 500g of dimethyl carbonate, adding 1.0g (25mmol) of potassium hydride under the protection of nitrogen, stirring for 15min at room temperature, heating to 60 ℃, slowly adding 125ml (2.0mmol) of iodomethane dropwise, maintaining the reaction temperature at 60 ℃, reacting for 0.5h, cooling the system to room temperature, slowly adding 500g of saturated potassium chloride aqueous solution to terminate the reaction, extracting the obtained mixed solution for three times by 150g of diethyl carbonate, washing an organic layer for three times by 150ml of clear water, and drying in vacuum to obtain 95g of 2, 5-di-tert-butyl hydroquinone, wherein the yield is 95%, and the total reaction yield is 86%.

Example 3

(1) Preparation of 2, 5-di-tert-butylhydroquinone:

adding 55.0g (0.5mol) of hydroquinone into a three-neck flask, adding 40g of deionized water into the three-neck flask, stirring and heating to 90 ℃, adding 30g (0.4mol) of tert-butyl alcohol, slowly dropwise adding into the three-neck flask until the solid in the flask is completely dissolved, preparing a mixed solution of 81.5g (1.1mol) of tert-butyl alcohol and 0.3g of sulfuric acid, slowly dropwise adding into the three-neck flask, maintaining the reaction temperature at 90 ℃, reacting for 5 hours, cooling the system to room temperature after the reaction is finished, filtering, washing the obtained solid with 150ml of water for three times, and drying to obtain 97.9g of 2, 5-di-tert-butylhydroquinone with the yield of 88%.

(2) Preparation of 2, 5-di-tert-butyl-p-xylylene ether:

and (2) dissolving 89g (0.4mol) of the 2, 5-di-tert-butylhydroquinone prepared in the step (1) in 800g of THF, adding 0.17g (4mmol) of calcium hydride under the protection of nitrogen, stirring for 15min at room temperature, heating to 80 ℃, slowly dropwise adding 200ml (3.2mmol) of methyl iodide, maintaining the reaction temperature at 80 ℃, reacting for 2h, cooling the system to room temperature, slowly adding 500g of saturated sodium bromide aqueous solution to terminate the reaction, extracting the obtained mixed solution for three times by 200g of petroleum ether, washing the organic layer for three times by 200ml of clear water, and drying in vacuum to obtain 92g of 2, 5-di-tert-butylhydroquinone, wherein the yield is 92% and the total reaction yield is 81%.

Example 4

(1) Preparation of 2, 5-di-tert-butylhydroquinone:

82.5g (0.75mol) of hydroquinone is taken and added into a three-neck flask, 60g of deionized water is added into the three-neck flask, the mixture is stirred and heated to 75 ℃, 75g (1.0mol) of tertiary butanol is taken and slowly dripped into the three-neck flask until the solid in the flask is completely dissolved, 203.8g (2.8mol) of tertiary butanol and 10g of glacial acetic acid are taken to prepare a mixed solution which is slowly dripped into the three-neck flask, the reaction temperature is maintained at 75 ℃, the reaction is carried out for 3 hours, the system is cooled to the room temperature after the reaction is finished, the mixture is filtered, the obtained solid is washed three times with 150ml of water and dried, and 150g of 2, 5-di-tert-butyl hydroquinone is obtained, and the yield.

(2) Preparation of 2, 5-di-tert-butyl-p-xylylene ether:

dissolving 89g (0.4mol) of 2, 5-di-tert-butyl hydroquinone prepared in the step (1) in 400g of diethyl carbonate, adding 2.46g (102.7mmol) of sodium hydride under the protection of nitrogen, stirring at room temperature for 15min, heating to 40 ℃, slowly adding 50ml (0.8mmol) of methyl iodide dropwise, maintaining the reaction temperature at 40 ℃, reacting for 1.5h, cooling the system to room temperature, slowly adding 500g of saturated saline solution to terminate the reaction, extracting the obtained mixed solution with 150g of ethyl acetate for three times, washing an organic layer with 150ml of clear water for three times, and drying in vacuum to obtain 85g of 2, 5-di-tert-butyl hydroquinone, wherein the yield is 90% and the total reaction yield is 81%.

Example 5

(1) Preparation of 2, 5-di-tert-butylhydroquinone:

93.5g (0.85mol) of hydroquinone is taken and added into a three-neck flask, 65g of deionized water is added into the three-neck flask, the mixture is stirred and heated to 90 ℃, 68g (0.92mol) of tertiary butanol is taken and slowly dripped into the three-neck flask until the solid in the flask is completely dissolved, 184.7g (2.5mol) of tertiary butanol and 5g of sulfuric acid are taken to prepare a mixed solution which is slowly dripped into the three-neck flask, the reaction temperature is maintained at 90 ℃, the reaction is carried out for 1h, the system is cooled to the room temperature after the reaction is finished, the mixture is filtered, the obtained solid is washed three times with 150ml of water and dried, and 170.2g of 2, 5-di-tert-butyl hydroquinone is obtained, and the yield.

(2) Preparation of 2, 5-di-tert-butyl-p-xylylene ether:

and (2) dissolving 80g (0.36mol) of the 2, 5-di-tert-butylhydroquinone prepared in the step (1) in 600g of methyl ethyl carbonate, adding 0.96g (40mmol) of sodium hydride under the protection of nitrogen, stirring for 15min at room temperature, heating to 50 ℃, slowly adding 172ml (1.53mmol) of methyl iodide dropwise, maintaining the reaction temperature at 50 ℃, reacting for 2h, cooling the system to room temperature, slowly adding 400g of saturated saline solution to terminate the reaction, extracting the obtained mixed solution for three times by 180g of dichloromethane, washing the organic layer for three times by 180ml of clear water, and drying in vacuum to obtain 84g of 2, 5-di-tert-butylhydroquinone, wherein the yield is 93 percent and the total reaction yield is 84 percent.