Method for preparing aryl vinyl sulfones

Abstract

A method for preparing an aryl vinyl sulfone includes the step of reacting an aryl sulfonyl halide in a first reaction mixture with a reactive solvent selected from (meth)acrylonitrile or alkyl (meth)acrylate in the presence of an uncomplexed Cu(I) catalyst to form an intermediate product. The unreacted reactive solvent is separated from the first reaction mixture to form a second reaction mixture. A low-polarity solvent is added to the second reaction mixture to precipitate the Cu(I) catalyst and dissolve the intermediate product to form a third reaction mixture. A base is added to the third reaction mixture, preferably under cooling, and the intermediate product undergoes elimination of halogen atoms from the intermediate product by a base catalyst to form an aryl vinyl sulfone compound. This aryl vinyl sulfone compound is separated from the third reaction mixture.

Description

Technical Field

[0001] The present invention relates to a method for preparing aryl vinyl sulfone from aryl sulfonyl halide.

Background Art

[0002] Aryl vinyl sulfone has various industrial applications. For example, 3-(arylsulfonyl)propenenitrile can be used as a biocide in industrial processes as disclosed in International Publication No. WO2019 / 042984 and International Publication No. WO2019 / 042985.

[0003] There are numerous methods for preparing aryl vinyl sulfone. However, most of these methods use solvents that are harmful to the environment, highly volatile, flammable, and / or difficult to obtain, such as acetonitrile. Furthermore, existing processes involve a large number of steps, thereby increasing the complexity of the process. Also, the possibility of recycling any of the chemical substances used in existing processes is limited.

[0004] An early example of such a process is described in Asscher, Vofsi, J. Chem. Soc., 1964, 4962 - 4971. This document describes a method of adding sulfonyl chloride to vinyl monomers and other olefins. The reaction of sulfonyl chloride with an olefin using a cupric chloride-based catalyst complex containing triethylammonium chloride is exemplified. Following the addition reaction with the olefin, a base-catalyzed dehydrohalogenation reaction occurs.

[0005] International Publication No. 2020 / 094917 describes a process for preparing arylsulfonylpropenenitrile. This process also proceeds by an addition reaction in which a sulfonyl halide is reacted with acrylonitrile and a catalyst, followed by a base-catalyzed elimination reaction to obtain the desired product. According to this disclosure, the catalyst complex is prepared by complexing an inorganic halide with a salt of an organic compound immediately before addition to the reaction mixture. The preparation of a cuprous iodide-based catalyst complex with triethylamine hydrochloride in acetonitrile is exemplified. Subsequently, tosyl loride is reacted with acrylonitrile in the presence of this catalyst complex.

[0006] These processes have several drawbacks as described above. Therefore, an object of the present invention is to provide an improved method for preparing aryl vinyl sulfones that minimizes or eliminates at least some of the drawbacks that occur in existing processes. [Overview of the project]

[0007] In a first embodiment of the present invention, a method for preparing a compound of formula (I) is provided. [ka] During the ceremony, R1, R2, and R3 are independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, a hydroxyalkyl group, a haloalkyl group, a carbon-1 to carbon-4 alkoxy group, an acyl group, an amino group, an alkylamino group, or a carbon-1 to carbon-10 acylamide group. A is a hydrogen atom, a C1-C5 alkyl group, or an alkoxycarbonyl group. B is a nitrile group, a carboxylic acid group, a carboxylic acid ester group, or a carboxylic acid amide group.

[0008] The above method, (a) In the presence of an uncomplexed Cu(I) catalyst, an aryl sulfonyl halide is reacted in a first reaction mixture with a reactive solvent selected from (meth)acrylonitrile or alkyl (meth)acrylate to form an intermediate product; (b) Separating the unreacted reactive solvent from the first reaction mixture to form a second reaction mixture, (c) Adding a low-polarity solvent to the second reaction mixture to precipitate the Cu(I) catalyst and dissolve the intermediate product to form a third reaction mixture, (d) A step of adding a base to the third reaction mixture, preferably under cooling, wherein the intermediate product undergoes the removal of halogen atoms from the intermediate product by a base catalyst to form the compound of formula (I), (e) The step of separating the compound according to formula (I) from the third reaction mixture is included.

[0009] Surprisingly, it was found that using an uncomplexed Cu(I) catalyst improves the method for preparing the compound of formula (I). This allows for higher yields. Furthermore, the method can be carried out at lower temperatures. The reactant composition is simplified, and the pretreatment step for generating the catalyst complex, which was previously considered essential in this method, is eliminated. The simplification of the method also makes it possible to easily reuse the reactants and catalyst materials.

[0010] In the context of the present invention, the uncomplexed Cu(I) catalyst contains monovalent copper ions, which may optionally be in the presence of counterions, and which have no ligands bound to them. This Cu(I) catalyst may be a Cu(I) halide catalyst having, for example, iodide, bromide, or chloride counterions. A preferred catalyst is a chloride Cu(I) catalyst. Typically, the Cu(I) halide is added to the first reaction mixture in solid form.

[0011] In one embodiment of the present invention, R1 in formula (I) is a hydrogen atom, a C1-C4 alkyl group, or a C1-C4 alkoxy group. R1 may also be a C1-C4 acyl group. R1 may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, or a tertiary butoxy group. Preferably, R1 is a methyl group at position 4.

[0012] In formula (I), R2 and R3 are, independently of each other and independently of R1, a hydrogen atom, a C1-C4 alkyl group, or a C1-C4 alkoxy group. R2 and / or R3 may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, or a tertiary butoxy group. Preferably, both R2 and R3 are hydrogen atoms.

[0013] According to one embodiment, R1, R2 and / or R3 in formula (I) may be, independently of each other, a halogen atom such as chlorine, fluorine, or bromine; a hydroxyl group; preferably a hydroxyalkyl group having 1 to 4 carbon atoms; preferably a haloalkyl group having 1 to 4 carbon atoms and / or a fluoro substituent such as trifluoromethyl; an amino group; an alkylamino group having 1 to 10 carbon atoms; or an acylamide group having 1 to 10 carbon atoms.

[0014] In a preferred embodiment, R1 is the methyl group at the 4-position of the aryl group, and both R2 and R3 are hydrogen atoms.

[0015] According to one embodiment, group A in formula (I) is a C1-C5 alkyl group or a hydrogen atom. Group A may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, or a pentyl group. Preferably, group A is a hydrogen atom.

[0016] According to one embodiment, group B in formula (I) is a nitrile group, a C1-C5 carboxylic acid group, a C1-C5 carboxylic acid ester group, or a C1-C5 carboxylic acid amide group.

[0017] According to one embodiment of the present invention, the compound of formula (I) may be arylsulfonylpropennitrile. The compound of formula (I) is 3-[(4-methylphenyl)sulfonyl]-2-propennitrile, 3-phenylsulfonyl-2-propennitrile, 3-[(4-fluorophenyl)sulfonyl]-2-propennitrile, 3-[(2,4-dimethylphenyl)sulfonyl]-2-propennitrile, 3-[(4-trifluoromethylphenyl)sulfonyl]-2-propennitrile, 3-(2,5-dimethylphenyl)sulfonyl-2-propennitrile, 3-[(2,4,6-trimethylphenyl)sulfonyl]-2-propennitrile, 3-(4-methoxyphenyl)sulfonyl-2-propennitrile, methyl(3-[(4-methylphenyl)sulfonyl]propen-2-enate, 3-(4-acetylf The compound may be selected from the group consisting of phenyl)sulfonyl-2-propennitrile and any of its isomers. According to a preferred embodiment of the present invention, the compound according to formula (I) is selected from the group consisting of 3-[(4-methylphenyl)sulfonyl]-2-propennitrile, 3-phenylsulfonyl-2-propennitrile, 3-[(4-trifluoromethylphenyl)sulfonyl]-2-propennitrile, 3-[(2,4,6-trimethylphenyl)sulfonyl]-2-propennitrile, 3-(4-methoxyphenyl)sulfonyl-2-propennitrile, 3-[(4-methylphenyl)sulfonyl]propen-2-enate and any of its isomers. Preferably, the compound according to formula (I) may also be 3-[(4-methylphenyl)sulfonyl]-2-propennitrile.

[0018] In the method of the present invention, the first reaction mixture is formed in solution form by mixing its components with each other. The first reaction mixture may be formed at a temperature of 15 to 40°C, preferably 20 to 30°C, and more preferably 25 to 30°C. The first reaction mixture can be formed at room temperature and has the advantage of not requiring heating.

[0019] The first reaction mixture comprises an aryl sulfonyl halide, a reactive solvent, and a Cu(I) catalyst.

[0020] The reactive solvent in the first reaction mixture is selected from (meth)acrylonitrile or alkyl (meth)acrylates, such as methyl acrylate or methyl methacrylate. Preferably, the reactive solvent is acrylonitrile. According to a preferred embodiment of the present invention, the first reaction mixture contains no solvents other than the reactive solvent. According to this embodiment, no solvents other than the reactive solvent are added to the first reaction mixture.

[0021] The Cu(I) catalyst defined above is dissolved in a reactive solvent, thereby obtaining a first reaction mixture in solution form. The reactive solvent functions as both a reactant and a solvent in the method according to the present invention. It is preferable to add an excess amount of the reactive solvent, which ensures the dissolution of the other components of the first reaction mixture. The reactive solvent has been found to be able to effectively dissolve the Cu(I) catalyst even at room temperature. As described above, heating is not required to form the first reaction mixture. Furthermore, the excess amount of reactive solvent promotes the desired reaction to obtain the intermediate product of the compound of formula (I). This simplifies the process and improves the conversion rate and / or yield of the process. However, the excess amount of reactive solvent to be added or required should be small.

[0022] The arylsulfonyl halide may be added to the first reaction mixture in one portion or sequentially in multiple portions. For example, it may be added sequentially in two, three or more times. Continuous addition is also possible. Preferably, the arylsulfonyl halide is added to the first reaction mixture in one portion. The arylsulfonyl halide may be benzenesulfonyl halide, alkyl-substituted benzenesulfonyl halide, or halo-substituted benzenesulfonyl halide. Examples thereof include toluenesulfonyl halide, xylenesulfonyl halide, 4-methoxybenzenesulfonyl halide, or 4-chlorobenzenesulfonyl halide. Preferably, it may be toluenesulfonyl chloride or toluenesulfonyl bromide, more preferably toluenesulfonyl chloride. For example, the arylsulfonyl halide may be 4-toluenesulfonyl halide, preferably 4-toluenesulfonyl chloride or 4-toluenesulfonyl bromide, more preferably 4-toluenesulfonyl chloride. The arylsulfonyl halide may be added in an amount of 0.3 to 0.7 equivalents, preferably 0.4 to 0.6 equivalents, more preferably about 0.5 equivalents (in mole units) based on the amount (in mole units) of the reactive solvent in the first reaction mixture. The arylsulfonyl halide is dissolved in the first reaction mixture under an exothermic process.

[0023] The amount of the Cu(I) catalyst in the first reaction mixture may be 5 to 30 mol%, preferably 10 to 25 mol%, more preferably 15 to 20 mol% calculated from the amount of the arylsulfonyl halide in the first reaction mixture.

[0024] An arylsulfonyl halide is added to the first reaction mixture. After its dissolution, the reaction is allowed to proceed at a high temperature, thereby obtaining an intermediate product. This reaction is a radical addition reaction. The reaction is preferably carried out at a high temperature that is higher than the boiling point of the reactive solvent but lower than the boiling point of the reaction mixture. The reaction in the first reaction mixture may proceed at a high temperature of 80 - 95 °C, preferably 85 - 92 °C, more preferably 85 - 87 °C. The reaction is allowed to proceed until the desired conversion rate of the intermediate product is obtained. The reaction time may be, for example, 10 - 30 hours, preferably 10 - 24 hours, more preferably 12 - 16 hours.

[0025] After the reaction has proceeded to the desired conversion rate, the unreacted reactive solvent can be separated from the first reaction mixture to form a second reaction mixture. The reactive solvent can be separated by any suitable separation method such as distillation. According to a preferred embodiment, after separating the reactive solvent from the first reaction mixture, it can be recycled by returning to step (a) of forming the first reaction mixture in the process. Thus, the unreacted reactive solvent can be reused in the preparation of the first reaction mixture, effectively reducing the amount of chemical waste generated. There is an advantage that little or no purification of the separated reactive solvent is required.

[0026] After separating the unreacted reactive solvent, a second reaction mixture is formed. This second reaction mixture contains the intermediate product and a Cu(I) catalyst. Then, a low-polarity solvent is added to the second reaction mixture. Thereby, the Cu(I) catalyst precipitates from the second reaction mixture and the intermediate product dissolves to form a third reaction mixture. This step may be carried out while the second reaction mixture is still at a high temperature following the reaction in the first reaction mixture. After adding the low-polarity solvent, the obtained third reaction mixture may be allowed to cool. At this stage, the precipitated Cu(I) catalyst may be removed from the third reaction mixture before further reactions occur.

[0027] The Cu(I) catalyst precipitate can be easily separated from the liquid phase of the third reaction mixture, which contains a low-polarity solvent and intermediate products, for example, by filtration. It is preferable to complete the removal prior to step (d) so that the Cu(I) catalyst is not contaminated or oxidized. Removal at this stage makes it possible to easily return the Cu(I) catalyst to step (a) for reuse. This has the advantage that there is no need to purify or reduce the catalyst.

[0028] To form the third reaction mixture, the relative polarity of the low-polarity solvent is less than 0.4, preferably less than 0.3, and even less than 0.25. In the context of this specification, values ​​of relative polarity shown in, for example, Reichardt, C (eds.) and Welton, T (eds.), "Solvents and Solvent Effects in Organic Chemistry," 4th edition, 2011, Wiley-VCH Verlag GmbH & Co., Weinheim, Appendix A, or other similar handbooks can be used. Because low-polarity solvents have low polarity, their ability to mix with water is reduced, making it easier to separate the intermediate product from the aqueous phase. Low-polarity solvents may also be considered hydrophobic. Low-polarity solvents may not contain carboxyl or hydroxyl groups. Suitable low-polarity solvents for use in the present invention may be selected from the group consisting of, for example, ethyl acetate, butyl acetate, tetrahydrofuran, dioxane, and toluene. According to one preferred embodiment, the low-polarity solvent is ethyl acetate.

[0029] The intermediate product is dissolved in a low-polarity solvent to form a third reaction mixture, and after separating the Cu(I) precipitate as needed, a base can be added to the third reaction mixture to eliminate the halogen atom from the intermediate product and form the compound of formula (I). The intermediate product undergoes an elimination reaction in the presence of a base, during which the halogen atom is removed from the intermediate product; that is, base-catalyzed elimination of the halogen atom occurs, yielding the compound of formula (I). The base used may be an inorganic base, an organic base, or a combination of an inorganic base and an organic base, and is preferably an organic base. Since the elimination reaction is exothermic, it is preferable to add the base under cooling to allow the elimination reaction to proceed. According to one preferred embodiment, the third reaction mixture is maintained at a temperature of 15 to 40°C, preferably 20 to 35°C, more preferably 20 to 25°C, while the halogen atom is eliminated from the intermediate product.

[0030] A base may be added to the third reaction mixture in an amount of at least 1 equivalent, preferably at least 1.3 equivalents (in moles) relative to the amount of intermediate dissolved in the second reaction mixture.

[0031] The base added to the third reaction mixture may preferably include an inorganic base selected from the group comprising alkali metal bicarbonates and carbonates, alkaline earth metal carbonates, or any mixture thereof. For example, the inorganic base may be selected from sodium bicarbonate, sodium carbonate, potassium bicarbonate, potassium carbonate, lithium bicarbonate, lithium carbonate, cesium carbonate, calcium carbonate, magnesium carbonate, or any mixture thereof. According to one preferred embodiment, sodium bicarbonate or sodium carbonate is used as the inorganic base.

[0032] The base added to the third reaction mixture preferably contains an organic base selected from trialkylamines such as triethylamine and trimethylamine; N-methylmorpholine; N-methylpyrrolidine; N,N-diisopropylethylamine (Hünig base); 1,4-diazabicyclo[2.2.2]octane (DABCO); 1,8-diazabicyclo[5.4.0]undeca-7-ene (DBU); or 1,5-diazabicyclo[4.3.0]nona-5-ene (DBN), or any mixture thereof. Triethylamine is preferred.

[0033] The base may include combinations of inorganic bases and organic bases as defined above.

[0034] According to one embodiment of the present invention, the third reaction mixture further contains water. Water may be introduced into the third reaction mixture before the addition of the base. When the base is added to the third reaction mixture, an elimination reaction proceeds.

[0035] In another embodiment of the present invention, water is added to the third reaction mixture simultaneously with or after the addition of the base. In this embodiment, the base is preferably a combination of the inorganic base and organic base defined above. The base may contain, in molar equivalents, 0.8 to 0.95 equivalents, preferably 0.9 to 0.95 equivalents of the inorganic base and 0.05 to 0.2 equivalents, preferably 0.05 to 0.1 equivalents of the organic base. The inorganic base and the organic base may be added to the third reaction mixture simultaneously or separately in sequence. Preferably, the inorganic base is added first, followed by the organic base.

[0036] In this alternative embodiment, the amount of water in the third reaction mixture may be 15 to 200% by weight, preferably 40 to 150% by weight, and more preferably 55 to 100% by weight, calculated from the amount of base in the third reaction mixture. Efficient stirring of the third reaction mixture while the elimination reaction is taking place prevents phase separation between water and the low-polarity solvent. Depending on the water content of the third reaction mixture, if both organic and inorganic bases are present, an interphase transfer process involving both is possible, improving the efficiency of the base-catalyzed elimination reaction.

[0037] After the elimination reaction is complete, the compound according to formula (I) is separated from the third reaction mixture. Since the reaction mixture contains an immiscible aqueous phase and an organic phase, the unwanted aqueous phase can be easily separated. The organic phase contains a precipitate of the compound according to formula (I), which can be easily separated from the organic solvent phase, for example, by filtration. This filtrate may be washed with an acid such as dilute hydrochloric acid. The relatively pure compound according to formula (I) can be obtained as a solid or semi-solid product. This product may be recrystallized from a C1-C3 alcohol, preferably isopropyl alcohol. This is followed by filtration and evaporation of the solvent. By recrystallization, the E-isomer is usually recovered with a purity of at least 99.5%.

[0038] As used herein and throughout the claims, the term “comprises” means “includes” or “consists of.” This term means to include at least the feature following it, but does not exclude other features not expressly mentioned. The term may also mean an element consisting only of the feature following it. [Modes for carrying out the invention]

[0039] The present invention will be described in further detail by reference only to the following examples. [Examples]

[0040] All chemicals and reagents used in this embodiment were reagent-grade in purity unless otherwise specified.

[0041] Preparation of intermediate products At room temperature, 2.74 g of Cu(I) chloride, 34 g of p-toluenesulfonyl chloride, and 20 g of acrylonitrile were mixed in a reactor. The mixture was heated to a temperature between 85°C and 87°C and stirred for 16 hours while maintaining this temperature. Excess acrylonitrile was removed by vacuum distillation at a temperature between 72°C and 92°C. 50 g of ethyl acetate was added to the remaining mixture, which was then stirred and allowed to cool. As a result, greenish-grayish-white catalyst particles precipitated. The residual mixture contained intermediate products.

[0042] Catalyst removal The catalyst precipitate was removed when the mixture reached approximately 45°C. This catalyst can be reused after washing twice with 5g of ethyl acetate, drying, and storing under a nitrogen atmosphere.

[0043] Desorption reaction After removing the catalyst, the reaction mixture was cooled to room temperature. 25 g of water was added, followed by 18.2 g of triethylamine. The temperature was maintained below 25°C. Two solvent layers formed. The aqueous layer was removed. The organic layer contained a yellowish-white precipitate of p-toluenesulfonylpropennitrile product. This precipitate was separated by filtration and washed twice with dilute hydrochloric acid.

[0044] recrystallization The product after the washing step contained residual solvent, so this was evaporated. 30 g of isopropyl alcohol was added to the resulting solid product and stirred thoroughly until completely dissolved. The solution was left to stand overnight at a refrigerated temperature of 6°C to form crystals. These crystals were filtered, washed with chilled isopropyl alcohol, and then dried at 45°C under a nitrogen atmosphere. The yield was 73%. Analysis of the product revealed that it was E-3-[(4-methylphenyl)sulfonyl]-2-propennitrile.

Claims

1. A method for preparing the compound of formula (I), 【Chemistry 1】 During the ceremony, R1, R2, and R3 are independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, a hydroxyalkyl group, a haloalkyl group, a carbon-1 to carbon-4 alkoxy group, an acyl group, an amino group, an alkylamino group, or a carbon-1 to carbon-10 acylamide group. A is a hydrogen atom, a C1-C5 alkyl group, or an alkoxycarbonyl group. B is a nitrile group, a carboxylic acid group, a carboxylic acid ester group, or a carboxylic acid amide group. The aforementioned method, (a) In the presence of an uncomplexed Cu(I) catalyst, an aryl sulfonyl halide is reacted in a first reaction mixture with a reactive solvent selected from (meth)acrylonitrile or alkyl (meth)acrylate to form an intermediate product; (b) Separating the unreacted reactive solvent from the first reaction mixture to form a second reaction mixture, (c) Adding a low-polarity solvent to the second reaction mixture to precipitate the Cu(I) catalyst and dissolve the intermediate product to form a third reaction mixture, (d) A step of adding a base to the third reaction mixture, preferably under cooling, wherein the intermediate product undergoes the removal of halogen atoms from the intermediate product by a base catalyst to form the compound of formula (I), (e) Separating the compound according to formula (I) from the third reaction mixture, A method that includes this.

2. The method according to claim 1, wherein in step (c), the intermediate product is dissolved in a low-polarity solvent having a relative polarity of less than 0.4 to form the third reaction mixture.

3. The method according to claim 1 or claim 2, wherein the low-polarity solvent is selected from ethyl acetate, butyl acetate, tetrahydrofuran, dioxane, and toluene.

4. The method according to any one of claims 1, 2, or 3, wherein the reaction in the first reaction mixture in step (a) is carried out at a temperature of 80 to 95°C, preferably 85 to 92°C, and more preferably 85 to 87°C.

5. The method according to any one of claims 1 to 4, wherein the reactive solvent separated from the first reaction mixture in step (b) is preferably returned to step (a) and reused by a distillation step.

6. The method according to any one of claims 1 to 5, wherein the Cu(I) catalyst precipitated from the second reaction mixture in step (c) is removed prior to step (d).

7. The method according to claim 6, wherein the Cu(I) catalyst precipitated from the second reaction mixture in step (c) is preferably returned to step (a) and reused without purification.

8. The method according to any one of claims 1 to 7, wherein in step (d), the base is added to the third reaction mixture in an amount of at least 1 molar equivalent with respect to the amount of the intermediate product dissolved in the third reaction mixture.

9. The method according to any one of claims 1 to 8, wherein the base in step (d) preferably comprises an inorganic base selected from alkali metal bicarbonates or carbonates, alkaline earth metal carbonates, or any mixture thereof.

10. The method according to any one of claims 1 to 9, wherein the base in step (d) preferably comprises an organic base selected from trialkylamines such as triethylamine and trimethylamine, N-methylmorpholine, N-methylpyrrolidine, N,N-diisopropylethylamine, 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undeca-7-ene, or 1,5-diazabicyclo[4.3.0]nona-5-ene.

11. The method according to any one of claims 1 to 10, wherein the amount of the Cu(I) catalyst in the first reaction mixture is 5 to 30 mol%, preferably 10 to 25 mol%, and more preferably 15 to 20 mol%, calculated from the amount of the aryl sulfonyl halide in the first reaction mixture.

12. The method according to any one of claims 1 to 11, wherein the Cu(I) catalyst is a Cu(I) halide catalyst, preferably Cu(I) chloride.

13. The method according to any one of claims 1 to 12, wherein the aryl sulfonyl halide is present in the first reaction mixture of step (a) in an amount of 0.3 to 0.7 equivalents, preferably 0.4 to 0.6 equivalents, and more preferably about 0.5 equivalents, relative to the amount of the reactive solvent.

14. The method according to any one of claims 1 to 13, wherein the compound according to formula (I) is recrystallized from an alcohol solvent after the separation step (e).

15. The method according to any one of claims 1 to 14, wherein the compound according to formula (I) is 3-[(4-methylphenyl)sulfonyl]-2-propenenitrile.

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