JP2021080211A - Method for producing (meth)acrylic acid anhydride - Google Patents

Abstract

To provide an industrially useful method for producing a (meth)acrylic acid anhydride capable of producing a (meth)acrylic acid anhydride with high yield and high purity.SOLUTION: There is provided a method for producing a (meth)acrylic acid anhydride by reacting a (meth)acrylic acid alkali metal salt and sulfonyl chloride in an organic solvent. The (meth)acrylic acid alkali metal salt includes lithium (meth)acrylate, sodium (meth)acrylate, potassium (meth)acrylate or the like. Among these (meth)acrylic acid alkali metal salts, preferable are sodium acrylate, potassium acrylate, sodium methacrylate and potassium methacrylate in consideration of market feedability, reactivity and easiness of treatment after the reaction. In addition, the sulfonyl chloride includes benzenesulfonyl chloride, p-toluenesulfonyl chloride and methanesulfonyl chloride.SELECTED DRAWING: None

Description

The present invention relates to a method for producing (meth) acrylic anhydride.

As a method for producing an acrylic anhydride and a methacrylic anhydride (hereinafter, both are collectively referred to as "(meth) acrylic anhydride"), a method of reacting an acid chloride with a carboxylic acid (Patent Document 1), an acid chloride and the like. A method of reacting a carboxylic acid metal salt (Non-Patent Document 1), a method of reacting a higher carboxylic acid with anhydrous acetic acid (Patent Document 2 and Non-Patent Document 2), and a method of reacting a carboxylic acid with sulfonyl chloride (Non-Patent Document 3). 4. Various methods are known, such as a method of reacting an acrylic acid metal salt with an inorganic acid chloride (Patent Document 4), a method of reacting an acrylic acid with diketen (Patent Document 5), and the like.

Japanese Unexamined Patent Publication No. 09-104642 Japanese Unexamined Patent Publication No. 05-339194 Japanese Unexamined Patent Publication No. 2004-035523 Japanese Patent Application Laid-Open No. 55-089242 U.S. Pat. No. 2,476859

J. Org. Chem., 60 (7) 2271, 1995 J. Am. Chem. Soc., Vol. 63, p.699, 1941 J. Chem. Res., Synop., P.100, 1984 Lett. Org. Chem., Vol. 14, No. 6, 2017

Since acid chloride is difficult to supply stably and is relatively expensive, the method containing acid chloride as a raw material is not industrially useful.
Further, in the method of reacting a higher carboxylic acid with acetic anhydride, a mixed acid anhydride of a carboxylic acid and acetic anhydride is produced, which needs to be removed, but it is difficult to completely remove it, and it is highly pure. It is difficult to obtain (meth) acrylic anhydride. Further, since the step for removing the mixed acid anhydride is performed at a high temperature, it is not suitable for the synthesis of a low boiling point (meth) acrylic anhydride.

The method of reacting a carboxylic acid with a sulfonyl chloride requires water treatment and rectification to remove triethylamine present in the system (Non-Patent Documents 3 and 3), and carbonates and sulfonyl salts are added in the system. It is not suitable for industrial practice because a large amount of solvent is required for formation (Non-Patent Document 4) and the like.

The method of reacting an acrylic acid metal salt with an inorganic acid chloride described in Patent Document 4 generates a large amount of sulfur dioxide, so that it is necessary to use a container or device made of a material having corrosion resistance. In addition, it is difficult to remove a trace amount of sulfur dioxide mixed in the product, and it is very difficult to obtain a high-purity acrylic anhydride.
The method described in Patent Document 5 has the disadvantages that the reaction proceeds extremely slowly and the yield is low.

An object to be solved by the present invention is to provide an industrially useful method for producing (meth) acrylic anhydride, which can produce (meth) acrylic anhydride in high yield and with high purity. ..

In the method for producing (meth) acrylic anhydride, the present inventors mainly produce (meth) acrylic anhydride in high yield and high, focusing on materials whose raw materials are inexpensive and easily available industrially. As a result of searching for a reaction system that can be produced with purity, a simple production method was found, and the present invention was reached.

That is, the present invention is a method for producing a (meth) acrylic anhydride, which comprises reacting a (meth) acrylic acid alkali metal salt with a sulfonyl chloride in an organic solvent.
In the present invention, "(meth) acrylic acid" means a general term for acrylic acid and methacrylic acid as has been conventionally used.

The production method of the present invention does not require triethylamine or the like as a catalyst, and does not require a water treatment step. Therefore, by using the production method of the present invention, (meth) acrylic anhydride can be easily produced both laboratoryally and industrially, and (meth) acrylic anhydride can be produced in high yield. Moreover, it can be produced with high purity.

In the present invention, the (meth) acrylic anhydride is produced by reacting a (meth) acrylic acid alkali metal salt with a sulfonyl chloride in an organic solvent.

Examples of the (meth) acrylic acid alkali metal salt used in the present invention include (meth) lithium acrylate, sodium (meth) acrylate, potassium (meth) acrylate and the like. Among these (meth) acrylic acid alkali metal salts, sodium acrylate, potassium acrylate, sodium methacrylate, and potassium methacrylate are preferable in consideration of market availability, reactivity, and ease of post-reaction treatment. ..

Examples of the sulfonyl chloride used in the present invention include benzenesulfonyl chloride, p-toluenesulfonyl chloride and methanesulfonyl chloride. All of these are excellent in terms of market availability, reactivity, and ease of processing.

Examples of the organic solvent used in the present invention include dichloromethane, acetone, dimethoxyethane, THF (tetrahydrofuran), dioxane, methyl cyclopentyl ether, acetonitrile, toluene and the like. Among these solvents, the low boiling point (the high boiling point solvent azeotropes the target (meth) acrylic acid anhydride, which leads to a decrease in yield), the side reactivity in the system is low, and the yield is low. Dichloromethane, acetone, THF and dimethoxyethane are more preferred in view of their high rate and low cost. All of these four types of solvents exemplified can be used, but dichloromethane has a problem of environmental regulation, and compounds having an ether bond (THF and dimethoxyethane, methyl cyclopentyl ether, etc.) are present in a trace amount in the system. Acetone is most preferred as it can induce polymerization of epoxiside.

Of the eight types of organic solvents mentioned above, in order to confirm azeotrope of dichloromethane, acetone, dimethoxyethane, dioxane, toluene and acrylate anhydride, 10.0 g of acrylate anhydride and 180 ml of solvent were mixed at 4.2 kPa. Concentration under reduced pressure was performed. Table 1 summarizes the results.

In the production method of the present invention, a (meth) acrylic acid alkali metal salt is added to a solvent, and sulfonyl chloride is added at about 20 ° C. while stirring and dispersing. Then, the desired (meth) acrylic anhydride can be obtained in good yield only by confirming the disappearance of the raw material by gas chromatography (GC), filtering, concentrating the solvent, and then distilling. .. At this time, if any of the above-mentioned four kinds of solvents is used, the (meth) acrylic acid alkali metal salt can be obtained in an amount of 1 to 6 times, preferably 2 to 3 times the amount of the (meth) acrylic acid alkali metal salt. Since it is sufficiently dispersed, the amount of solvent used can be small.

Typical reaction examples of the present invention and their chemical reaction formulas are shown below.

From the above chemical reaction formula, 2 mol of sodium (meth) acrylate reacts with 1 mol of p-methanesulfonyl chloride, p-benzenesulfonyl chloride, and p-toluenesulfonyl chloride (hereinafter referred to as PTS-Cl, etc.) to 1 mol (hereinafter referred to as PTS-Cl, etc.). It is clear that a meta) acrylate anhydride can be obtained, but industrially, the amount of PTS-Cl or the like is reduced to 0.98 mol or less than 1 mol with respect to 2 mol of sodium (meth) acrylate. Is preferable. This is because if PTS-Cl or the like is present in the reaction system in the treatment or distillation step, PTS-Cl or the like may be dissociated into a corrosive acid, which may adversely affect the (meth) acrylic anhydride produced as a product. This is to avoid the occurrence of unreacted PTS-Cl and the like.

In the present invention, the reaction proceeds by dispersing the alkali metal salt in the solvent and adding sulfonyl chloride in the dispersed state. Since this reaction is an exothermic reaction, sulfonyl chloride is added little by little at appropriate times, or the reaction is carried out in the range of 0 ° C. to 70 ° C., preferably room temperature to 50 ° C. The reaction is continued until PTS-Cl disappears, checking with a gas chromatograph (GC). Normal reaction times range from 2 o'clock to 48 hours. In this reaction system, there is a high possibility that polymerization will proceed, so it is advisable to add a polymerization inhibitor to prevent polymerization from occurring. Examples of polymerization inhibitors include phenothiazine, hydroquinone, 4-methoxyphenol, 2,6-di-tert-butyl-p-cresol, 2-hydroxy-1,4-naphthoquinone, tetra (C12 to C15 alkyl) -4, Any of 4'-isopropyridene diphenyldiphosphite and various commercially available polymerization inhibitors may be used, and two or more thereof may be used.
Generally, a polymerization inhibitor of 5 ppm to 500 ppm can be used with respect to the alkali metal salt, and it is more preferable to use a polymerization inhibitor of 100 to 300 ppm.

After the above reaction, the desired acrylic anhydride and methacrylic anhydride can be obtained with high purity and high yield by filtering, concentrating the solvent, and then distilling under reduced pressure. As described above, the desired acid anhydride can be obtained by a simple operation without requiring a water treatment and a drying step with a desiccant.

Hereinafter, specific examples of the present invention will be described in detail, but the present invention is not limited thereto. In the following examples, the identification of (meth) acrylic anhydride was performed by gas chromatography (hereinafter referred to as GC). In addition, 200 ppm of 4-methoxyphenol, which is a polymerization inhibitor, was added to the (meth) acrylic anhydride after distillation.

[Example 1]
<Synthesis of acrylic anhydride; sodium acrylate, p-toluenesulfonyl chloride (TsCl) system>
Add 77.7 mL of acetone, 25.9 g (0.28 mol) of sodium acrylate, 25.9 mg of 4-methoxyphenol and 25.9 mg of phenothiazine at 25 ° C while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. , Stirred and dispersed. To this, 25.0 g (0.13 mol) of TsCl was added. After that, it was aged for 48 hours. The conversion rate of the crude body was 98.7%.

After completion of the reaction, the mixture was filtered using a filter paper, washed 3 times with 100 ml of acetone, and then acetone was distilled off under reduced pressure to 16.3 g of crude acrylic anhydride (crude yield 98.6% with respect to TsCl, GC). purity
92.4%) was obtained.
Subsequently, the crude product was distilled under reduced pressure under pure air to obtain 14.1 g of acrylic anhydride (bp 40 ° C. (O.4 kPa), yield 85.2% with respect to TsCl, GC purity 99.6%).

[Example 2]
<Synthesis of acrylic anhydride; sodium acrylate, methanesulfonyl chloride (MsCl) system>
129.3 mL of acetone, 43.1 g (0.46 mol) of sodium acrylate, 43.1 mg of 4-methoxyphenol, and 43.1 mg of phenothiazine under an ice bath while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. It was charged, stirred and dispersed. 25.0 g (0.22 mol) of MsCl was added dropwise thereto over 5 minutes. Then, the mixture was stirred under an ice bath, and when it was confirmed that the exotherm had subsided, the outside temperature was set to 25 ° C., and the reaction was followed by GC while aging for 2 hours, and it was confirmed that MsCl had disappeared. The conversion rate of the braid at that time was 99.8%.

After completion of the reaction, the mixture was filtered using a filter paper, washed 3 times with 100 ml of acetone, and then the acetone was distilled off under reduced pressure to obtain 27.7 g of crude acrylic anhydride (100.7% of assembly yield based on MsCl, GC). Purity 96.6%) was obtained.
Subsequently, the crude product was distilled under reduced pressure under pure air to obtain 24.9 g of acrylic anhydride (bp 40 ° C. (O.4 kPa), yield 90.7% with respect to MsCl, GC purity 99.1%).

[Example 3]
<Synthesis of acrylate anhydride; potassium acrylate, TsCl type>
Acetone 91.0 mL, potassium acrylate 30.3 g (0.28 mol), 4-methoxyphenol 30.3 mg, and phenothiazine 30.3 mg at 25 ° C while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. It was charged, stirred and dispersed. To this, 25.0 g (0.13 mol) of TsCl was added. After that, it was aged for 7 hours. The conversion rate of the crude body was 98.7%.

After completion of the reaction, the mixture was filtered using a filter paper, washed with 100 ml of acetone three times, and then acetone was distilled off under reduced pressure to obtain 16.6 g of crude acrylic anhydride (crude yield 100.3% with respect to TsCl, GC). Purity 94.7%) was obtained.
Subsequently, the crude product was distilled under reduced pressure under pure air to obtain 14.5 g of acrylic anhydride (bp 40 ° C. (O.4 kPa), yield 90.5% with respect to TsCl, GC purity 99.1%).

[Example 4]
<Synthesis of acrylic anhydride; potassium acrylate, MsCl type>
Acetone 151.5 mL, potassium acrylate 50.5 g (0.46 mol), 4-methoxyphenonole 50.5 mg, and phenothiazine 50.5 mg under an ice bath while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. Was charged, stirred and dispersed. 25.0 g (0.22 mol) of MsCl was added dropwise thereto over 30 minutes. Then, the mixture was stirred under an ice bath, and when it was confirmed that the exotherm had subsided, the outside temperature was set to 25 ° C., and the reaction was followed by GC while aging for 1 hour. As a result, it was confirmed that MsCl had disappeared. The conversion rate of the crude body was 99.1%.

After completion of the reaction, the mixture was filtered using a filter paper, washed with 100 mL of acetone three times, and then acetone was distilled off under reduced pressure to obtain 28.5 g of crude acrylic anhydride (crude yield 103.5% with respect to MsCl, GC). Purity 95.3%) was obtained.
The crude product was distilled under reduced pressure under pure air to obtain 25.7 g of acrylic anhydride (bp 40 ° C. (O.4 kPa), yield 93.3% with respect to MsCl, GC purity 99.3%).

[Example 5]
<Synthesis of methacrylic anhydride; sodium methacrylate, TsCl type>
Acetone 89.3 mL, sodium methacrylate 29.8 g (0.28 mol, 4-methoxyphenol 29.8 mg, and phenothiazine 29.8 mg) were charged at 25 ° C while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. , Stirred and dispersed, and 25.0 g (0.13 mol) of TsCl was added thereto. Then, when the reaction was followed by GC while aging for 7 hours, it was confirmed that TsCl had disappeared. The conversion rate of the body was 99.6%.

After completion of the reaction, the mixture was filtered using a filter paper, washed with 100 ml of acetone three times, and then acetone was distilled off under reduced pressure to obtain 20.9 g of crude methacrylic anhydride (crude yield 103.4% with respect to TsCl, GC). Purity 94.6%) was obtained.
Subsequently, the crude product was distilled under reduced pressure under pure air to obtain 17.8 g of methacrylic anhydride (bp 53 ° C. (O.4 kPa), yield 87.9% with respect to TsCl, GC purity 99.6%).

[Example 6]
<Synthesis of methacrylic anhydride; sodium methacrylate, MsCl type>
148.6 mL of acetone, 49.5 g (0.46 mol) of sodium methacrylate, 49.5 mg of 4-methoxyphenol, and 49.5 mg of phenothiazine under an ice bath while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. It was charged, stirred and dispersed. 25.0 g (0.22 mol) of MsCl was added dropwise thereto over 5 minutes. Then, the mixture was stirred under an ice bath, and when it was confirmed that the exotherm had subsided, the outside temperature was set to 25 ° C., and the reaction was followed by GC while aging for 1 hour. As a result, it was confirmed that MsCl had disappeared. The conversion rate of the crude material was 100.0%.

After completion of the reaction, the mixture was filtered using a filter paper, washed 3 times with 100 ml of acetone, and then the acetone was distilled off under reduced pressure to obtain 34.6 g of crude methacrylic anhydride (crude yield 102.8% with respect to MsCl). GC purity 97.7%) was obtained.
The crude product was distilled under reduced pressure under pure air to obtain 31.0 g of methacrylic anhydride (bp53 ° C. (O.4 kPa), yield 92.1% with respect to MsCl, GC purity 99.2%).

[Example 7]
<Synthesis of methacrylic anhydride; potassium methacrylate, TsCl type>
Acetone 102.6 mL, potassium methacrylate 34.2 g (0.28 mol), 4-methoxyphenol 34.2 mg, and phenothiazine 34.2 mg at 25 ° C while passing pure air through a 300 ml four-necked flask equipped with a stirrer and a thermometer. It was charged, stirred and dispersed. 25.0 g (0.13 mol) of TsCl was added thereto. Then, while aging for 3 hours, the reaction was followed by GC, and it was confirmed that TsCl disappeared. The conversion rate of the crude body was 99.6%.

After completion of the reaction, the mixture was filtered using a filter paper, washed with 100 ml of acetone three times, and then acetone was distilled off under reduced pressure to obtain 16.5 g of crude methacrylic anhydride (crude yield 100.0% based on TsCl, GC). Purity 95.6%) was obtained.
Subsequently, the crude product was distilled under reduced pressure under pure air to obtain 14.7 g of methacrylic anhydride (bp 53 ° C. (O.4 kPa), yield 88.7% with respect to TsCl, GC purity 99.4%).

[Example 8]
<Synthesis of methacrylic anhydride; potassium methacrylate, MsCl type>
In a 300 ml four-necked flask equipped with a stirrer and a thermometer, pure air was charged with 148.6 mL of acetone, 49.5 g (0.46 mol) of potassium methacrylate, 49.5 mg of 4-methoxyphenol, and 49.5 mg of phenothiazine under an ice bath. It was stirred and dispersed. 25.0 g (0.22 mol) of MsCl was added dropwise thereto over 30 minutes. Then, the mixture was stirred under an ice bath, and when it was confirmed that the exotherm had subsided, the outside temperature was set to 25 ° C., and the reaction was followed by GC while aging for 1 hour. As a result, it was confirmed that MsCl had disappeared. The conversion rate of the crude body was 99.0%.

After completion of the reaction, the mixture was filtered using a filter paper, washed 3 times with 100 mL of acetone, and then the acetone was distilled off under reduced pressure to obtain 27.8 g of crude methacrylic anhydride (crude yield 101.0% with respect to MsCl, GC). Purity 98.0%) was obtained.
Subsequently, the crude product was distilled under reduced pressure under pure air to obtain 26.1 g of methacrylic anhydride (bp53 ° C. (O.4 kPa), yield 94.8% with respect to MsCl, GC purity 99.6%).

The results of Examples 1 to 8 are summarized in Table 2 below.

Claims (4)

A method for producing a (meth) acrylic anhydride, which comprises reacting a (meth) acrylic acid alkali metal salt with a sulfonyl chloride in an organic solvent. In the manufacturing method according to claim 1,
The (meth) acrylic acid alkali metal salt is selected from the group consisting of lithium acrylate, sodium acrylate, potassium acrylate, lithium methacrylate, sodium methacrylate, and potassium methacrylate. Method for producing acid anhydride. In the manufacturing method according to claim 1 or 2.
A method for producing a (meth) acrylic anhydride, wherein the sulfonyl chloride is a benzenesulfonyl chloride, a p-toluenesulfonyl chloride or a methanesulfonyl chloride. In the manufacturing method according to any one of claims 1 to 3.
A method for producing a (meth) acrylic anhydride, wherein the organic solvent is selected from the group consisting of dichloromethane, acetone, dimethoxyethane, THF, dioxane, acetonitrile, and toluene.