JP5496750B2 - Method for producing α, β-unsaturated ester - Google Patents

Description

  The present invention relates to a method for producing an α, β-unsaturated ester having a 2-oxo-1,3-dioxolane structure, which is useful as a raw material for paints and functional polymers, a raw material for pharmaceuticals, agricultural chemicals and other fine chemicals. .

An α, β-unsaturated ester having an oxirane structure (hereinafter referred to as oxirane ester) and carbon dioxide are reacted to form an α, β-unsaturated ester having a 2-oxo-1,3-dioxolane structure (hereinafter referred to as 2 -Oxo-1,3-dioxolane ester) is produced by using a quaternary ammonium compound or phosphane as a catalyst, an alkali metal or alkaline earth metal halide as a co-catalyst, and a temperature of 100 to A production method by reacting with carbon dioxide at 150 ° C. under normal pressure is known (Patent Document 1).
However, in the conventional method, the yield of 2-oxo-1,3-dioxolane ester is low, and industrially satisfactory results are not obtained. In particular, when an oxirane ester having a disubstituted oxirane structure is used as a raw material, the yield is significantly reduced. For example, as described later in Examples, 3,4-epoxycyclohexylmethyl methacrylate is used as the oxirane ester. When the reaction was carried out under the conditions described in Patent Document 1, the yield of 2-oxo-1,3-dioxolane ester was low.

Japanese Patent No. 2565875

  Accordingly, an object of the present invention is to provide a method for producing 2-oxo-1,3-dioxolane ester in a high yield and low cost by a simple operation in order to solve the problems of the background art described above. It is in.

According to the present invention, the above problem is
In the method for producing 2-oxo-1,3-dioxolane ester by reacting oxirane ester and carbon dioxide, the reaction is carried out in the presence of an alkali metal salt, a quaternary ammonium salt, and an N-oxyl compound. This is accomplished by providing a manufacturing method.

  According to the present invention, 2-oxo-1,3-dioxolane ester can be produced by a simple operation at high yield and low cost.

The oxirane ester used as a raw material compound in the present invention comprises an α, β-unsaturated carboxylic acid residue and an epoxy alcohol residue.
Examples of the α, β-unsaturated carboxylic acid residue in the oxirane ester used as a raw material compound in the present invention include an acrylic acid residue, a methacrylic acid residue, a crotonic acid residue, and a 2- (trifluoromethyl) acrylic acid residue. Group and the like.

  The epoxy alcohol residue in the oxirane ester used as a raw material compound in the present invention is only required to contain an epoxy group in the residue. For example, an epoxy alcohol residue corresponding to the epoxy alcohol represented by the following formula is used. be able to.

  In the epoxy alcohol residue, a substituent such as a halogen atom, cyano group, amide group, hydroxy group, amino group, ester group, ether group, carboxyl group, silyl group, alkyl group, cycloalkyl group, aromatic group is added. It may be an epoxy alcohol residue.

  Although the example of the oxirane ester used as a raw material compound by this invention is shown below, it is not limited to these at all.

(In the formula, R represents a hydrogen atom, a methyl group, or a trifluoromethyl group)

(Wherein R is as defined above).

  Among the oxirane esters, when an oxirane ester having an oxirane structure having two or more substitutions is used as a raw material, the present invention is preferable, and more preferable in an oxirane ester having an alicyclic alkylene oxide structure. More preferred is epoxy cyclohexyl methyl methacrylate.

  In some cases, the oxirane ester used as a raw material compound in the present invention can be purchased on the market, and the esterification reaction of the corresponding epoxy alcohol, the epoxy of α, β-unsaturated ester having the corresponding unsaturated alcohol residue It can also be produced by a chemical reaction.

  The carbon dioxide used in the present invention can be used alone or can be mixed with an inert gas such as nitrogen, argon or helium to be used for the reaction. The carbon dioxide pressure is preferably normal pressure. As a supply method, it may be blown into the liquid phase part or into the gas phase part.

  The alkali metal halide used in the present invention is, for example, a halide of lithium, sodium, or potassium. Specifically, lithium fluoride, sodium fluoride, potassium fluoride, lithium chloride, sodium chloride, potassium chloride, Examples thereof include lithium bromide, sodium bromide, potassium bromide, lithium iodide, sodium iodide, and potassium iodide. From the viewpoint of reaction rate, lithium fluoride, lithium chloride, lithium bromide, and lithium iodide are preferable. More preferred is lithium iodide.

The quaternary ammonium salt that is a catalyst used in the present invention has the following formula:

(In the above formula, R ¹ , R ² , R ³ and R ⁴ each represent an alkyl group having 1 to 4 carbon atoms or a benzyl group. X represents a chlorine atom, a bromine atom or an iodine atom.)
Specifically, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, tetrabutylammonium chloride, tetrabutylammonium bromide , Tetrabutylammonium iodide, trimethylbenzylammonium chloride, triethylbenzylammonium chloride, tributylammonium chloride, and the like. From the viewpoint of reaction rate, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide are preferred, and tetrabutylammonium iodide is preferred. Ammonium bromide is more preferred.

  The alkali metal halide and quaternary ammonium salt used in the present invention exhibit catalytic action even when used alone. However, the alkali metal halide has a large catalytic action because an alkali metal cation acts as a Lewis acid, but its solubility in the reaction system is poor and the amount to be dissolved is limited. In addition, depending on the application, there are those that need to reduce the residual metal in the object as much as possible, and it may be desirable to reduce the amount used at the time of reaction. On the other hand, the quaternary ammonium salt has high solubility in the reaction system, but its use amount increases because of its generally high molecular weight. Therefore, in order to maximize the effect of the alkali metal halide and the quaternary ammonium salt as a catalyst and to minimize the amount used, it is necessary to mix them in an appropriate ratio in terms of reactivity, economy and quality. It is important for all to be satisfied, and it is preferable to use a quaternary ammonium salt in the range of 0.1 to 10 mol, and in the range of 0.2 to 5 mol, per mol of the alkali metal halide. More preferably.

  There are no particular restrictions on the amount of alkali metal halide and quaternary ammonium salt, but the total amount of alkali metal halide and quaternary ammonium salt is usually 0.001 to 10 moles per mole of oxirane ester. From the viewpoint of properties, it is preferably used in the range of 0.001 to 1 mol.

  Examples of the N-oxyl compound used in the present invention include 2,2,6,6-tetramethylpiperidine-N-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4- Methoxy-2,2,6,6-tetramethylpiperazine-N-oxyl, 4-acetoxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-acetylamino-2,2,6,6 -Tetramethylpiperidine-N-oxyl, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 2,2,6,6-tetramethyl-4-stearoyloxypiperidine-N-oxyl Bis (2,2,6,6-tetramethyl-N-oxylpiperidyl) malate, bis (2,2,6,6-tetramethyl-N-oxylpiperidyl) 2,2,6,6-tetramethylpiperidine-N-oxyl compounds such as tarate, tris (2,2,6,6-tetramethyl-N-oxylpiperidyl) butane-1,2,3-tricarboxylate 8,8,10,10-tetramethyl-3-methyl-3-hydroxymethyl-N-oxyl-1,5-dioxa-9-azaspiro [5.5] undecane; cyclohexane-1-spiro-2′- (4′-oxoimidazolidine-1′-oxyl) -5′-spiro-1 ″ -cyclohexane and the like can be mentioned, and 2,2,6,6-tetramethylpiperidine-N-oxyl compounds are preferable.

  The present invention is carried out in the presence or absence of a solvent. When a solvent is used, any solvent can be used as long as it does not adversely influence the reaction. For example, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, diethyl ether, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, 1,2-bis (2-methoxyethoxy) ethane, diisopropylether, t- Ether compounds such as butyl methyl ether and cyclopentyl methyl ether; dimethyl sulfoxide; ketone compounds such as acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclopentanone and cyclohexanone; formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N -Methylacetamide, N, N-dimethylacetamide, 1-methyl-2-pyrrolidinone, 1-ethyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, etc. Such as bromide compounds. These may be used alone or in combination. Among these, from the viewpoint of reaction rate and selectivity, an amide compound is preferable, and 1-methyl-2-pyrrolidinone is more preferable.

  Although the usage-amount of the solvent used by this invention is not specifically limited, 0.1 to 100 times with respect to the mass of oxirane ester, and 1 to 10 times is more preferable from a viewpoint of coexistence of a reactivity and economical efficiency.

  The reaction temperature of the present invention is preferably 50 to 150 ° C., and more preferably 80 to 120 ° C. from the viewpoint of achieving both reaction rate and selectivity.

  The reaction of the present invention can be carried out at normal pressure or under pressure, but normal pressure that is simple in terms of operation is preferred.

  The isolation and purification of 2-oxo-1,3-dioxolane ester, which is the target product of this reaction, is not particularly limited, and can be carried out by a usual procedure for handling organic compounds. For example, the solvent is removed by concentrating the reaction solution under reduced pressure and dissolved in an appropriate solvent, and then the catalyst is removed by washing with water. Subsequently, the concentrate obtained by distilling off the solvent is distilled and subjected to column chromatography. Conventionally used organic compound purification methods such as chromatography and recrystallization can be used.

  Examples of the 2-oxo-1,3-dioxolane ester obtained by the method of the present invention include, but are not limited to, those represented by the following formula.

(Wherein R is as defined above).

EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not restrict | limited by these.

<Example 1>
In a 2 L three-necked flask equipped with a mechanical stirrer, reflux tube, and carbon dioxide introduction tube, 3,4-epoxycyclohexylmethyl methacrylate 400.0 g (2.04 mol), N-methyl-2-pyrrolidinone 1204 g, tetrabutylammonium After sequentially adding 65.72 g (203 mmol) of bromide, 4.43 g (51.0 mmol) of lithium bromide and 0.40 g of 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl, the mixture was stirred. At the same time, carbon dioxide was blown into the liquid phase part at a rate of 0.20 L / min, and heating was started. The internal temperature was stirred in the range of 100 to 104 ° C. for 24 hours. As a result of quantitative analysis by gas chromatography, the conversion was 88.1%, and the selectivity was 93.2%. The solvent was distilled off from the reaction solution at a pressure of less than 133 Pa and a temperature of 76 to 104 ° C. to obtain 529 g of a concentrate. The concentrate and 1058 g of toluene were mixed and washed 3 times with 529 g of water, then 0.10 g of 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl was added, and the pressure was 6.6 KPa, The solution was concentrated under reduced pressure at a temperature of 50 ° C. to obtain a distilled stock solution. For distillation, a molecular distillation apparatus “MS-300” (manufactured by SHIBATA) was used. A high-boiling fraction obtained by flowing the distillation stock solution at a pressure of 13.3 to 26.6 Pa and a temperature of 90 ° C. is flowed at a pressure of 5.3 to 6.7 Pa and a temperature of 115 to 125 ° C. 307.0 g of (2,4-dioxabicyclo [4.3.0] nonan-3-one-7-yl) methyl methacrylate (purity 98.8%, 1.26 mol) was obtained as a liquid (yield 61 .9%).

<Comparative Example 1>
In a 50 mL three-necked flask equipped with a magnetic stirrer, reflux tube and carbon dioxide introduction tube, 16.3 g (83.2 mmol) of 3,4-epoxycyclohexylmethyl methacrylate and 0.11 g (0.41 mmol) of triphenylphosphine , Potassium iodide 0.30 mmol) and 25 mg of hydroquinone monomethyl ether were added, and the mixture was heated and stirred at 80 ° C. for 5 hours while bubbling carbon dioxide at 20 mL / min. When the reaction solution was analyzed by gas chromatography, the target product was not detected.

<Comparative example 2>
In Comparative Example 1, the same procedure was followed except that 0.11 g (0.41 mmol) of triphenylphosphine was replaced with 0.056 g (0.30 mmol) of benzyltrimethylammonium chloride, and the mixture was heated at 100 ° C. for 5 hours. When the reaction solution was analyzed by gas chromatography, the target product was not detected. To the reaction solution, 0.770 g (4.15 mmol) of benzyltrimethylammonium chloride was added, and carbon dioxide was bubbled at 20 mL / min, and the mixture was heated and stirred at 100 ° C. for 2 hours, and the reaction solution was analyzed by gas chromatography. As a result, the target product was not detected.

<Comparative Example 3>
In Comparative Example 1, the same procedure was followed, except that 0.11 g (0.41 mmol) of triphenylphosphine was replaced with 46.7 mg (0.41 mmol) of 1,4-diazabicyclo [2.2.0] octane. The mixture was stirred with heating at 5 ° C. for 5 hours. When the reaction solution was analyzed by gas chromatography, the target product was not detected.

<Example 2>
In a 2 L three-necked flask equipped with a mechanical stirrer, reflux tube and carbon dioxide introduction tube, 290.0 g (2.04 mol) of glycidyl methacrylate, 1204 g of 1-methyl-2-pyrrolidinone, 65.72 g (203 mmol) of tetrabutylammonium bromide ), 4.43 g (51.0 mmol) of lithium bromide, and 0.40 g of 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl in this order, and then carbon dioxide was reduced to 0 with stirring. At the same time as blowing into the liquid phase at a rate of 20 L / min, heating was started. The internal temperature was stirred in the range of 100 to 102 ° C. for 5 hours. As a result of quantitative analysis by gas chromatography, the conversion was 92.1%, and the selectivity was 94.0%.

<Comparative Example 4>
In a 50 mL three-necked flask equipped with a magnetic stirrer, a reflux tube, and a carbon dioxide introduction tube, 11.8 g (83.2 mmol) of glycidyl methacrylate, 0.11 g (0.41 mmol) of triphenylphosphine, 0. 30 mmol) and 25 mg of hydroquinone monomethyl ether were added, and the mixture was heated and stirred at 82 to 84 ° C. for 5 hours while bubbling carbon dioxide at 20 mL / min. As a result of quantitative analysis by gas chromatography, the conversion was 18.0% and the selectivity was 88.0%.

<Comparative Example 5>
In Comparative Example 4, the same procedure was followed except that 0.11 g (0.41 mmol) of triphenylphosphine was replaced with 0.056 g (0.30 mmol) of benzyltrimethylammonium chloride, and the mixture was heated at 100 ° C. for 5 hours. As a result of quantitative analysis by gas chromatography, the conversion was 82.3% and the selectivity was 29.9%.

<Comparative Example 6>
In Comparative Example 4, the same procedure was followed, except that 0.11 g (0.41 mmol) of triphenylphosphine was replaced with 46.7 mg (0.41 mmol) of 1,4-diazabicyclo [2.2.0] octane. The mixture was stirred with heating at 5 ° C. for 5 hours. As a result of quantitative analysis by gas chromatography, the conversion was 10.3% and the selectivity was 81.0%.

<Example 3>
In a 50 mL three-necked flask equipped with a magnetic stirrer, a reflux tube, and a carbon dioxide introduction tube, 5.00 g (25.5 mol) of 3,4-epoxycyclohexylmethyl methacrylate, 25.00 g of 1-methyl-2-pyrrolidinone, Tetrabutylammonium bromide 0.82 g (2.55 mmol), lithium bromide 0.22 g (2.55 mmol), 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl 5.0 mg sequentially After the addition, carbon dioxide was blown into the liquid phase part at a rate of 10 to 20 mL / min with stirring, and heating was started at the same time. After stirring at an internal temperature of 100 ° C. for 4.0 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Example 4>
In Example 3, the same operation was performed except that 0.22 g (2.55 mmol) of lithium bromide was replaced with 55.0 mg (0.64 mmol) of lithium bromide. After stirring at an internal temperature of 100 ° C. for 4.2 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Example 5>
In Example 3, the same operation was carried out except that 0.22 g (2.55 mmol) of lithium bromide was replaced with 55.0 mg (0.64 mmol) of lithium bromide and 25.00 g of NMP were replaced with 15.0 g. After stirring at an internal temperature of 100 ° C. for 4.2 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Comparative Example 7>
In a 50 mL three-necked flask equipped with a magnetic stirrer, a reflux tube, and a carbon dioxide introduction tube, 5.00 g (25.5 mol) of 3,4-epoxycyclohexylmethyl methacrylate, 25.00 g of 1-methyl-2-pyrrolidinone, Tetrabutylammonium bromide 0.82 g (2.55 mmol), lithium bromide 55.0 mg (0.64 mmol) and hydroquinone monomethyl ether 20.0 mg were sequentially added, and carbon dioxide was added at a rate of 10 to 20 mL / min with stirring. Then, heating was started simultaneously with blowing into the liquid phase part. After stirring at an internal temperature of 100 ° C. for 4.0 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Comparative Example 8>
In a 50 mL three-necked flask equipped with a magnetic stirrer, a reflux tube, and a carbon dioxide introduction tube, 5.00 g (25.5 mol) of 3,4-epoxycyclohexylmethyl methacrylate, 25.00 g of 1-methyl-2-pyrrolidinone, After sequentially adding 0.11 g (2.55 mmol) of lithium chloride and 5.0 mg of 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl, 10 to 20 mL /% of carbon dioxide was added with stirring. Heating was started simultaneously with blowing into the liquid phase part at a rate of minutes. After stirring for 4.1 hours at an internal temperature of 100 ° C., the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Comparative Example 9>
The same operation as in Comparative Example 8 was conducted except that 0.11 g (2.55 mmol) of lithium chloride was replaced with 0.22 g (2.55 mmol) of lithium bromide. After stirring at an internal temperature of 100 ° C. for 4.0 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Comparative Example 10>
The same operation as in Comparative Example 8 was conducted except that 0.11 g (2.55 mmol) of lithium chloride was replaced with 0.59 g (2.55 mmol) of benzyltrimethylammonium bromide. After stirring at an internal temperature of 100 ° C. for 3.8 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Comparative Example 11>
The same operation as in Comparative Example 8 was conducted except that 0.11 g (2.55 mmol) of lithium chloride was replaced with 0.82 g (2.55 mmol) of tetrabutylammonium bromide. After stirring at an internal temperature of 100 ° C. for 4.0 hours, the reaction solution was collected and quantitatively analyzed by gas chromatography. The results are shown in Table 1.

<Example 6>
In a 50 mL three-necked flask equipped with a magnetic stirrer, reflux tube and carbon dioxide introduction tube, 5.00 g (25.5 mol) of 3,4-epoxycyclohexylmethyl methacrylate, 25.0 g of 1-methyl-2-pyrrolidinone, Tetrabutylammonium bromide 0.82 g (2.55 mmol), lithium bromide 55.0 mg (0.64 mmol), 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl 5.0 mg sequentially After the addition, carbon dioxide was blown into the liquid phase part at a rate of 10 to 20 mL / min with stirring, and heating was started at the same time. After stirring at an internal temperature of 100 ° C. for 4.0 hours, the reaction solution was collected and analyzed by gas chromatography. Both conversion and selectivity were calculated from area percentage values. The results are shown in Table 2.

<Example 7>
The same operation as in Example 6 was performed except that 1-methyl-2-pyrrolidinone was replaced with N, N-dimethylformamide in Example 6. After stirring at an internal temperature of 100 ° C. for 4.0 hours, the reaction solution was collected and analyzed by gas chromatography. Both conversion and selectivity were calculated from area percentage values. The results are shown in Table 2.

<Example 8>
The same operation as in Example 6 was performed except that 1-methyl-2-pyrrolidinone was replaced with dimethyl sulfoxide in Example 6. After stirring for 4.1 hours at an internal temperature of 100 ° C., the reaction solution was collected and analyzed by gas chromatography. Both conversion and selectivity were calculated from area percentage values. The results are shown in Table 2.

<Example 9>
The same operation as in Example 6 was performed except that 1-methyl-2-pyrrolidinone was replaced with 1,2-bis (2-methoxyethoxy) ethane in Example 6. After stirring for 4.1 hours at an internal temperature of 100 ° C., the reaction solution was collected and analyzed by gas chromatography. Both conversion and selectivity were calculated from area percentage values. The results are shown in Table 2.

<Example 10>
The same operation as in Example 6 was performed except that 1-methyl-2-pyrrolidinone was replaced with cyclohexanone in Example 6. After stirring for 4.1 hours at an internal temperature of 100 ° C., the reaction solution was collected and analyzed by gas chromatography. Both conversion and selectivity were calculated from area percentage values. The results are shown in Table 2.

Claims (4)

  In a method for producing an α, β-unsaturated ester having a 2-oxo-1,3-dioxolane structure by reacting an α, β-unsaturated ester having an oxirane structure with carbon dioxide, an alkali metal salt, quaternary ammonium The production method, wherein the reaction is carried out in the presence of a salt and an N-oxyl compound. The method according to claim 1, wherein the N-oxyl compound is 2,2,6,6-tetramethylpiperidine-N-oxyl compound. The production method according to claim 1 or 2, wherein the reaction is carried out in the presence of an amide compound.   The method according to any one of claims 1 to 3, wherein the α, β-unsaturated ester having an oxirane structure is 3,4-epoxycyclohexylmethyl methacrylate.