KR102504826B1 - Method for producing hydroxy-substituted dimethyldioxolone - Google Patents

Abstract

The present invention provides a method for producing hydroxy-substituted dimethyldioxolone comprising a step of heating after adding dimethyldioxolone to a solution in which a non-metal oxide is mixed in an aprotic solvent. Since the above production method can produce hydroxy-substituted dimethyldioxolone from dimethyldioxolone in a single process, process time and cost can be drastically reduced.

Description

Method for producing hydroxy-substituted dimethyldioxolone {METHOD FOR PRODUCING HYDROXY-SUBSTITUTED DIMETHYLDIOXOLONE}

The present invention relates to a method for preparing hydroxy-substituted dimethyldioxolone. Specifically, the present invention relates to a method of substituting a hydroxy group for a methyl group of 4,5-dimethyl-1,3-dioxol-2-one in a shorter process.

Lithium secondary batteries are widely used in portable electronic products due to their characteristics such as high operating voltage, high stability, and long lifespan. Recently, with the development of electric vehicles, various applications are expected for new products such as electric vehicles.

As a composition of a lithium secondary battery, the non-aqueous electrolyte basically moves lithium ions so that lithium ions can be intercalated and deintercalated in the positive and negative electrodes during the charging and discharging process of the battery. . In addition, because of its high reactivity, the non-aqueous electrolyte reacts on the surface of the negative electrode to form compounds such as Li ₂ CO ₃ , LiO, and LiOH, thereby forming a passivation film called a solid electrolyte interface film (SEI) on the surface of the negative electrode. The SEI film formed during the initial charging process not only prevents the electrolyte from further decomposing in the negative electrode, but also serves as a lithium ion passage, affecting the performance of the lithium secondary battery.

In order to improve the performance of lithium secondary batteries, researchers in the relevant technical field have continuously studied ways to improve the performance of non-aqueous electrolytes, and added electrolyte additives such as vinylene carbonate to improve the performance of lithium secondary batteries. and developed methods to improve it. The vinylene carbonate causes a reduction and decomposition reaction on the surface of the negative electrode before solvent molecules do, thereby forming a passivation film on the surface of the negative electrode, preventing further decomposition of the electrolyte on the surface of the electrode, thereby improving the cycle function of the battery. can improve However, when vinylene carbonate is added, problems such as expansion of the battery due to gas generation during high-temperature storage or high resistance of the formed passivation film may occur. To improve these problems, vinylene carbonate derivatives are sometimes used. .

Among the vinylene carbonate derivatives, 4-hydroxymethyl-5-methyl-1,3-dioxol-2-one (4-Hydroxymethyl-5-methyl-1,3-dioxol-2-one) is It is a compound with a structure.

[Formula 1]

The 4-hydroxymethyl-5-methyl-1,3-dioxol-2-one is generally 4,5-dimethyl-1,3-dioxol-2-one (4, 5-Dimethyl-1,3-dioxol-2-one) by substituting hydrogen in the methyl group with a hydroxyl group. In the present specification, the group 4,5-dimethyl-1,3-dioxol-2-one is also referred to as dimethyldioxolone, and 4-hydroxymethyl-5-methyl-1,3-dioxol-2-one is also expressed as hydroxy-substituted dimethyldioxolone.

[Formula 2]

Conventionally, the hydroxy-substituted dimethyldioxolone was prepared from dimethyldioxolone through a three-step process. The three-step process is configured as shown in Scheme 1 below.

[Scheme 1]

The first step of the three-step process is a step of replacing the hydrogen of the methyl group in dimethyldioxolone with bromine. In the first step, dimethyldioxolone is mixed with N-Bromosuccinimide (NBS) and azo-bis-isobuty in 1,2-dichloroethane (1,2-DCE). After adding to the solution to which nitrile (Azo-bis-isobutyronitrile, AIBN) was added, refluxing and stirring at 100 ° C. for 4 hours, bromine-substituted dimethyldioxolone (4-bromomethyl-5-methyl-1, 3-dioxol-2-one (4-Bromomethyl-5-methyl-1,3-dioxol-2-one) is prepared.

The second step of the three-step process is a step of substituting bromine with a formyloxy group in the bromine-substituted dimethyldioxolone produced in the first step. In the second step, after stirring by adding bromine-substituted dimethyldioxolone to a mixed solution of formic acid and acetonitrile (Acetonitrile, MeCN), triethylamine (TEA) was added dropwise, and 2 by reacting for an hour, formyloxy-substituted dimethyldioxolone ((5-methyl-2-oxo-1,3-dioxol-4yl)methyl formate ((5-Methyl-2-oxo-1,3- dioxol-4-yl)methyl formate)) is prepared.

The third step of the three-step process is a step of replacing the formyloxy group with a hydroxy group in the formyloxy-substituted dimethyldioxolone produced in the second step. In the third step, methanol (Methanol, MeOH) and hydrochloric acid (HCl) aqueous solution were added to the solution containing the formyloxy-substituted dimethyldioxolone prepared in the second step, stirred, and left at room temperature for 5 hours to obtain hydroxyl -Preparation of substituted dimethyldioxolone.

The above-described conventional method for producing hydroxy-substituted dimethyldioxolone is not efficient because it requires a considerable amount of processing time and cost for each step. Therefore, there is a need for an efficient method for producing hydroxy-substituted dimethyldioxolone in the art.

Marco Alpegiani et al., On the Preparation of 4-Hydroxymethyl-5-Methyl-1,3-Dioxol-2-One, Synthetic Communications (1992), 22(9), 1277-1282

In order to solve the problems of the process time and cost of the conventional hydroxy-substituted dimethyldioxolone manufacturing method, the present invention is a hydroxy-substituted dimethyldioxolone capable of producing hydroxy-substituted dimethyldioxolone in a single process from dimethyldioxolone. -It is intended to provide a method for producing substituted dimethyldioxolone.

According to the first aspect of the present invention,

The present invention provides a method for producing hydroxy-substituted dimethyldioxolone comprising a step of heating after adding dimethyldioxolone to a solution in which a non-metal oxide is mixed in an aprotic solvent.

In one embodiment of the present invention, the aprotic solvent is tetrahydrofuran or 1,4-dioxane.

In one embodiment of the present invention, the non-metal oxide is SeO ₂ .

In one embodiment of the present invention, heating in the production step is performed at 105 ° C to 140 ° C.

In one embodiment of the present invention, a process of refluxing and stirring together with heating is performed in the production step.

In one embodiment of the present invention, in the production step, dimethyldioxolone and non-metal oxide are mixed to a molar ratio of 1:2 to 1:3.

In one embodiment of the present invention, the amount of the aprotic solvent in the production step is 1.0M to 5.0M based on the total number of moles of dimethyldioxolone and nonmetal oxide after mixing dimethyldioxolone and nonmetal oxide. concentration is adjusted.

In one embodiment of the present invention, the production method further comprises a separation step of distilling the solution after the production step under reduced pressure to remove the solvent, and extracting the remaining material to obtain hydroxy-substituted dimethyldioxolone.

In one embodiment of the present invention, in the separation step, the extraction is performed by adding water and an organic solvent separated from water to the remaining material, and hydroxy-substituted dimethyldioxolone is separated into an organic solvent layer by extraction do.

In one embodiment of the present invention, the extraction is performed by adding water and an organic solvent at a volume ratio of 1:1.1 to 1:3.

In one embodiment of the present invention, the organic solvent includes methylene chloride.

In one embodiment of the present invention, the organic solvent layer produced after extraction in the separation step is distilled under reduced pressure to remove the organic solvent, and hydroxy-substituted dimethyldioxolone is obtained.

Since the method for producing hydroxy-substituted dimethyldioxolone according to the present invention can produce hydroxy-substituted dimethyldioxolone in a single process from dimethyldioxolone, process time and cost can be drastically reduced.

The embodiments provided according to the present invention can all be achieved by the following description. The following description should be understood to describe preferred embodiments of the present invention, and it should be understood that the present invention is not necessarily limited thereto.

Regarding the physical properties described in this specification, when the measurement conditions and methods are not specifically described, the physical properties are measured according to measurement conditions and methods generally used by those skilled in the art.

The present invention provides a method for producing hydroxy-substituted dimethyldioxolone comprising a step of heating after adding dimethyldioxolone to a solution in which a non-metal oxide is mixed in an aprotic solvent. Conventionally, since a total of three steps must be performed to produce hydroxy-substituted dimethyldioxolone from dimethyldioxolone, it is not preferable in terms of process time and cost. In contrast, according to the method for producing hydroxy-substituted dimethyldioxolone of the present invention, since hydroxy-substituted dimethyldioxolone can be produced from dimethyldioxolone in a single process, process time and cost are drastically reduced. can do. The process of producing hydroxy-substituted dimethyldioxolone and then separating it from a solvent is not significantly different from the conventional method and the method according to the present invention in that a vacuum distillation method is generally used.

In the present invention, in order to prepare hydroxy-substituted dimethyldioxolone, first, dimethyldioxolone is added to a solvent in which a non-metal oxide is mixed with an aprotic solvent. The aprotic solvent is not particularly limited as long as it effectively disperses dimethyldioxolone and non-metal oxide and does not cause a side reaction with dimethyldioxolone or non-metal oxide. According to one embodiment of the present invention, the aprotic solvent is tetrahydrofuran or 1,4-dioxane, preferably 1,4-dioxane.

The non-metal oxide is not particularly limited as long as it reacts with dimethyldioxolone to introduce a hydroxyl group into dimethyldioxolone. According to one embodiment of the present invention, the non-metal oxide is SeO ₂ .

When dimethyldioxolone and non-metal oxide are mixed in an aprotic solvent, the ratio of each component is appropriately adjusted within the range where dimethyldioxolone reacts with non-metal oxide and dimethyldioxolone introduces a hydroxyl group in high yield. It can be. According to one embodiment of the present invention, the dimethyldioxolone and the non-metal oxide are mixed in a molar ratio of 1:2 to 1:3. The aprotic solvent may be appropriately adjusted within a range in which dimethyldioxolone and the non-metal oxide can be uniformly dispersed while maintaining an appropriate distance for the reaction to occur. According to one embodiment of the present invention, the amount of the aprotic solvent is adjusted to a molar concentration of 1.0M to 5.0M after mixing dimethyldioxolone and a non-metal oxide. The molar concentration is calculated based on the total number of moles of dimethyldioxolone and non-metal oxide.

After mixing dimethyldioxolone and non-metal oxide in an aprotic solvent, the resulting solution is heated to react dimethyldioxolone with non-metal oxide. Heating is performed at a temperature higher than the boiling point of the aprotic solvent, and the solution is refluxed and stirred to increase the reactivity of dimethyldioxolane and non-metal oxides. According to one embodiment of the present invention, the heating is performed at 105 °C to 140 °C.

The method for producing hydroxy-substituted dimethyldioxolone according to the present invention further comprises a separation step of distilling the solution after the production step under reduced pressure to remove the solvent and extracting the remaining material to obtain hydroxy-substituted dimethyldioxolone. do. The separation step is a process of separating and obtaining the hydroxy-substituted dimethyldioxolane produced by the above-described production step.

The solution after the production step is distilled under reduced pressure to remove the solvent, and the remaining material is separated into hydroxy-substituted dimethyldioxolane and other materials through extraction. The extraction is performed by adding water and an organic solvent separated from the water to the remaining material. As the water, deionized water (DIW) may be used to prevent side reactions from occurring. The organic solvent is not particularly limited as long as it can be separated from water to form an organic solvent layer. The organic solvent may preferably be an ether-based solvent, and according to one embodiment of the present invention, petroleum ether is used.

The ratio of the water to the organic solvent may be appropriately adjusted within a range capable of increasing extraction efficiency. Since hydroxy-substituted dimethyldioxolane is separated into the organic solvent layer during the extraction process, it may be preferable to add a large amount of organic solvent rather than water. According to one embodiment of the present invention, water and organic solvent are added in a volume ratio of 1:1.1 to 1:3 in the extraction process.

In order to increase the extraction efficiency of hydroxy-substituted dimethyldioxolane in the extraction process, the organic solvent may include methylene chloride (MC). The methylene chloride has a high affinity with hydroxy-substituted dimethyldioxolane, so when mixed, the hydroxy-substituted dimethyldioxolane contained in the water layer can be extracted more effectively, and the miscibility is high with ether-based organic solvents. Finally, it is included in the organic solvent layer. According to one embodiment of the present invention, the organic solvent includes 10 to 30% by volume of methylene chloride based on the total volume of the organic solvent.

The extraction process may be repeatedly performed to increase the extraction efficiency of hydroxy-substituted dimethyldioxolane, and only methylene chloride may be separately added to the water layer.

The organic solvent layer produced after extraction in the separation step is distilled under reduced pressure to remove the organic solvent, and hydroxy-substituted dimethyldioxolone is obtained. In order to increase the yield in the process of obtaining the hydroxy-substituted dimethyldioxolone, an impurity removal process such as vacuum filtration may be performed.

Hereinafter, preferred embodiments are presented to aid understanding of the present invention, but the following examples are provided to more easily understand the present invention, but the present invention is not limited thereto.

Example

Example One

After adding 20 g of dimethyldioxolone and 50 g of SeO ₂ to 200 ml of 1,4-dioxane, the resulting mixed solution was heated to 120°C. The evaporated solvent was cooled to 10° C. or less, and the mixed solution was continuously stirred while being refluxed, and the reactants were reacted for 2 hours. After the reaction, the mixed solution was sufficiently cooled at room temperature and filtered under reduced pressure on a Celite pad. After filtration, the filtered solution was distilled under reduced pressure to remove the solvent. After removing the solvent, 300 ml of deionized water and 500 ml of an organic solvent (a mixed solvent of petroleum ether and methylene chloride in a volume ratio of 4:1) were added to the remaining material, and the mixture was thoroughly mixed and extracted three times. Thereafter, after separating the water layer, 400 ml of methylene chloride was added to the water layer, thoroughly mixed, and extracted 4 times. The extracted organic layer was collected, dried using MgSO ₄ , and filtered again under reduced pressure on a celite pad. After filtration, the filtered solution was distilled under reduced pressure to remove 80% of the solvent. After removing 80% of the solvent, the concentrated solution was additionally filtered under reduced pressure to remove red solid impurities. After distilling the filtered solution under reduced pressure to completely remove the solvent, hydroxy-substituted dimethyldioxolone was obtained. The production process of hydroxy-substituted dimethyldioxolone according to Example 1 is schematically shown in Scheme 2 below.

[Scheme 2]

The obtained material has the following NMR results (device: JMTC-400/54/JJ/YH), and through the results below, it can be confirmed that the target material, hydroxy-substituted dimethyldioxolone, was produced.

¹ H-NMR (400 MHz, CDCl ₃ ): 4.41 (s, 2H, -CH ₂ ), 2.13 (s, 3H, -CH ₃ )

¹³ C-NMR (400 MHz, CDCl ₃ ): 9.17(-CH ₃ ), 52.92(-CH ₂ -OH), 137.40(-C-CH ₃ ), 153.23 (OC(O)-O-), 153.79(= C-CH ₂ -OH)

comparative example One

After adding 25 g of dimethyldioxolone, 30 g of N-bromosuccinimide and 2 g of azo-bis-isobutyronitrile to 1.5 L of 1,2-dichloroethane, the resulting mixed solution was heated to 100°C. did The evaporated solvent was cooled to 10° C. or less, and the mixed solution was continuously stirred while being refluxed, and the reactants were reacted for 4 hours. After the reaction, the mixed solution was distilled under reduced pressure to remove 50% of the solvent, and the concentrated solution was filtered under reduced pressure on a celite pad to remove impurities. The filtered solution was recrystallized from a mixed solution of benzene and cyclohexane in a volume ratio of 1:3 to obtain bromine-substituted dimethyldioxolone.

The obtained bromine-substituted dimethyldioxolone has the following NMR results.

¹ H-NMR (400 MHz, CDCl ₃ ): 4.31 (s, 2H, -CH ₂ ), 2.14 (s, 3H, -CH ₃ )

¹³ C-NMR (400 MHz, CDCl ₃ ): 10.35 (-CH ₃ ), 26.48 (-CH ₂ -Br), 156.10 (-C-CH ₂ -Br), 143.75 (-C-CH ₃ ), 150.27 (- C = O)

25 g of bromine-substituted dimethyldioxolone was added to 15 ml of formic acid and 400 ml of acetonitrile and stirred, and then 50 ml of triethylamine was added dropwise and reacted for 2 hours (here, formyloxy-substituted dimethyldioxolone was produced). ).

300 ml of methanol and 1 ml of 37% hydrochloric acid aqueous solution were added to the reaction mixture, stirred, and allowed to stand at room temperature for 5 hours. After the organic solvent layer was extracted, washed twice with a 37% aqueous hydrochloric acid solution, and the solution of the organic solvent layer was distilled under reduced pressure to completely remove the solvent to obtain hydroxy-substituted dimethyldioxolone.

The production process of hydroxy-substituted dimethyldioxolone according to Comparative Example 1 is schematically shown in Scheme 1 below.

[Scheme 1]

The obtained material has the following NMR results, and the following results are the same as those of Example 1, confirming that the target material, hydroxy-substituted dimethyldioxolone, was produced.

¹ H-NMR (400 MHz, CDCl ₃ ): 4.41 (s, 2H, -CH ₂ ), 2.13 (s, 3H, -CH ₃ )

¹³ C-NMR (400 MHz, CDCl ₃ ): 9.17(-CH ₃ ), 52.92(-CH ₂ -OH), 137.40(-C-CH ₃ ), 153.23 (OC(O)-O-), 153.79(= C-CH ₂ -OH)

All simple modifications or changes of the present invention belong to the scope of the present invention, and the specific protection scope of the present invention will be clarified by the appended claims.

Claims (12)

A production step of adding dimethyldioxolone to a solution of a mixture of a non-metal oxide in an aprotic solvent and then heating;
The non-metal oxide is SeO ₂ Method for producing hydroxy-substituted dimethyldioxolone. The method of claim 1,
The method for producing hydroxy-substituted dimethyldioxolone, characterized in that the aprotic solvent is tetrahydrofuran or 1,4-dioxane. delete The method of claim 1,
The method for producing hydroxy-substituted dimethyldioxolone, characterized in that the heating in the production step is carried out at 105 ℃ to 140 ℃. The method of claim 1,
Method for producing hydroxy-substituted dimethyldioxolone, characterized in that the process of refluxing and stirring with heating is performed in the production step. The method of claim 1,
In the production step, dimethyldioxolone and non-metal oxide are mixed to a molar ratio of 1:2 to 1:3. The method of claim 6,
In the production step, the amount of the aprotic solvent is adjusted to a molar concentration of 1.0M to 5.0M based on the total number of moles of dimethyldioxolone and nonmetal oxide after mixing dimethyldioxolone and nonmetal oxide. Method for preparing hydroxy-substituted dimethyldioxolone. The method of claim 1,
The manufacturing method further comprises a separation step of distilling the solution after the production step under reduced pressure to remove the solvent and extracting the remaining material to obtain hydroxy-substituted dimethyldioxolone Hydroxy-substituted dimethyldioxolone characterized in that How to make Solon. The method of claim 8,
In the separation step, extraction is performed by adding water and an organic solvent separated from water to the remaining material, and hydroxy-substituted dimethyldioxolone is separated into an organic solvent layer by extraction. Hydroxy-substituted Method for producing dimethyldioxolone. The method of claim 9,
The extraction is a method for producing hydroxy-substituted dimethyldioxolone, characterized in that carried out by adding water and an organic solvent in a volume ratio of 1: 1.1 to 1: 3. The method of claim 9,
The method for producing hydroxy-substituted dimethyldioxolone, characterized in that the organic solvent comprises methylene chloride. The method of claim 9,
Method for producing hydroxy-substituted dimethyldioxolone, characterized in that the organic solvent layer produced after extraction in the separation step is distilled under reduced pressure to remove the organic solvent, and to obtain hydroxy-substituted dimethyldioxolone.