Method for producing organosilicon compounds containing β-ketoester structure

Abstract

Provided is a method for producing a target product in a high yield in the hydrosilylation reaction of a hydrogen silane compound and a β-ketoester compound having an unsaturated bond. 【Solution means】 General formula (1) TIFF2026066587000012.tif7156 A hydrogen silane compound represented by General formula (2) TIFF2026066587000013.tif15155 A β-ketoester compound having an unsaturated bond represented by is subjected to a hydrosilylation reaction using a platinum catalyst in the presence of a ketone solvent. General formula (3) TIFF2026066587000014.tif16155 A method for producing a compound represented by.

Description

[Technical Field]

[0001] This invention relates to a method for producing organosilicon compounds containing a β-ketoester structure. [Background technology]

[0002] Organosilicon compounds having a hydrolyzable silyl group and an organic group allow for the bonding of organic and inorganic materials, which are normally difficult to bond, because the silanol group generated by the hydrolysis of the hydrolyzable silyl group forms a covalent bond with the hydroxyl group on the surface of the inorganic material, and the organic group further reacts with the organic material. This makes it possible to impart properties such as heat resistance, water resistance, weather resistance, improved mechanical strength, adhesion, dispersibility, hydrophobicity, and corrosion resistance to organic-inorganic composite materials. By utilizing these properties, the organosilicon compounds described above are used in a wide range of fields and applications, including silane coupling agents, resin additives, surface treatment agents, fiber treatment agents, adhesives, paint additives, and polymer modifiers.

[0003] Among the organosilicon compounds mentioned above, organosilicon compounds having a β-ketoester structure have the advantage of being able to improve the adhesion of organic-inorganic composite materials because the β-ketoester structure exhibits high reactivity with various organic and inorganic materials. Examples of organosilicon compounds having such a β-ketoester structure include 3-trimethoxysilylpropylacetoacetate (Patent Document 1). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2005-314325 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, organosilicon compounds having a β-ketoester structure as described in Patent Document 1 are synthesized by hydrosilylation of a hydrogensilane compound and a β-ketoester compound having an unsaturated bond using a platinum catalyst (main reaction), as shown in the scheme below. However, it is known that a thermal decomposition reaction of the product (side reaction 1) occurs during this reaction, and since this decomposition reaction is temperature-dependent, there is a problem that the yield decreases significantly at high reaction temperatures.

[0006] [ka]

[0007] Furthermore, if the reaction temperature is lowered to suppress the above-mentioned decomposition reaction, the reaction proceeds slowly, and as shown in the scheme below, multiple by-products are generated due to the disproportionation reaction (side reaction 2) and transesterification reaction (side reaction 3) of the hydrogen silane compound accumulated in the system, resulting in a decrease in yield. In other words, the disproportionation reaction produces by-products in which the hydrogen atoms and alkoxy groups of the hydrogen silane compound are mutually converted. In the transesterification reaction, by-products are produced in which the hydroxyl group of the enol form, which is a tautomer of the β-ketoester compound, is exchanged with the alkoxy group of the hydrogen silane compound. In addition, a dehydrogenation reaction (side reaction 4) occurs between the alcohol produced as a by-product in the transesterification reaction and the hydrogen silane compound.

[0008] [ka]

[0009] Therefore, in the hydrosilylation reaction of a hydrogensilane compound with a β-ketoester compound having an unsaturated bond, there is a need for a method that enhances the reactivity of the main hydrosilylation reaction while suppressing the multiple side reactions exemplified above, thereby producing organosilicon compounds containing a β-ketoester structure in high yield.

[0010] The present invention has been made in view of the above circumstances, and in the hydrosilylation reaction of a hydrogen silane compound and a β-ketoester compound having an unsaturated bond, while enhancing the reactivity of the main hydrosilylation reaction, suppressing a plurality of side reactions, and providing a method for producing an organosilicon compound containing a β-ketoester structure in a high yield.

Means for Solving the Problems

[0011] As a result of intensive studies to achieve the above problems, the present inventors have found that by subjecting a hydrogen silane compound and a β-ketoester compound having an unsaturated bond to a hydrosilylation reaction using a platinum catalyst in the presence of a ketone solvent, the reactivity of the main hydrosilylation reaction can be enhanced while suppressing a plurality of side reactions, and an organosilicon compound containing a β-ketoester structure can be produced in a high yield, thereby completing the invention.

[0012] That is, the present invention provides 1. A hydrogen silane compound represented by the following general formula (1)

Chemical formula

Chemical formula

[0013] According to the present invention's method for producing β-ketoester structure-containing organosilicon compounds, since the reaction is carried out in the presence of a ketone solvent, the ratio of tautomer keto-form chemical species to enol-form chemical species in the β-ketoester compound used as a starting material increases, resulting in increased reactivity of the main reaction, hydrosilylation. As a result, multiple side reactions are suppressed, and the target product can be produced in high yield. [Modes for carrying out the invention]

[0014] The present invention will be described in detail below. In this invention, a hydrosilylation reaction is carried out using a platinum catalyst in the presence of a ketone solvent to produce an organosilicon compound having a β-ketoester structure represented by the following general formula (3) (hereinafter referred to as "compound (3)"). This reaction involves a hydrogensilane compound represented by the following general formula (1) (hereinafter referred to as "compound (1)") and a β-ketoester compound having an unsaturated bond represented by the following general formula (2) (hereinafter referred to as "compound (2)").

[0015] [ka]

[0016] In general formula (1), R1 Each independently represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms. R 1 Specific examples of the halogen atom of 1 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 1 The monovalent hydrocarbon group of 1 may be linear, branched, or cyclic. Specific examples thereof include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; branched alkyl groups such as sec-propyl, sec-butyl, tert-butyl, sec-pentyl, tert-pentyl, sec-hexyl, tert-hexyl, sec-heptyl, tert-heptyl, sec-octyl, tert-octyl, sec-nonyl, tert-nonyl, sec-decyl, and tert-decyl groups; cyclic alkyl groups such as cyclopentyl and cyclohexyl groups; alkenyl groups such as vinyl, allyl, butenyl, and methallyl groups; aryl groups such as phenyl, tolyl, and xylyl groups; aralkyl groups such as benzyl and phenethyl groups, and the like.

[0017] Note that some or all of the hydrogen atoms of these monovalent hydrocarbon groups may be substituted with other substituents. Specific examples of this substituent include alkoxy groups having 1 to 3 carbon atoms such as methoxy, ethoxy, and (iso)propoxy groups; halogen atoms such as fluorine, chlorine, and bromine; aromatic hydrocarbon groups such as phenyl group; cyano group; amino group; ester group; ether group; carbonyl group; acyl group; sulfide group, and the like. One or more of these can be used in combination. The substitution position of these substituents is not particularly limited, and the number of substituents is also not limited.

[0018] Among these, R 1Preferably, the group consists of a hydrogen atom, a halogen atom, a substituted or unsubstituted linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms; a substituted or unsubstituted linear, branched, or cyclic alkenyl group having 2 to 6 carbon atoms; an aryl group; or an aralkyl group. Particularly from the viewpoint of the availability of precursor raw materials, a hydrogen atom, a halogen atom, an unsubstituted linear alkyl group having 1 to 3 carbon atoms; or an unsubstituted linear alkenyl group having 2 to 3 carbon atoms is more preferred, and a hydrogen atom, a chlorine atom, a methyl group, or an ethyl group is even more preferred.

[0019] In general formula (1), R 2 Each of these independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and a specific example thereof is R 1 Examples of substituents similar to those exemplified in [reference] include the monovalent hydrocarbon group.

[0020] In general formula (1), n ​​is an integer between 0 and 2. In particular, when compound (3) obtained by the hydrosilylation reaction described later is used as a silane coupling agent or resin additive, 0 or 1 is preferred from the viewpoint of reacting with multiple hydroxyl groups on the substrate surface to improve adhesion.

[0021] Specific examples of compound (1) include monohydrogensilane compounds such as trimethoxysilane, triethoxysilane, dimethoxymethylsilane, and diethoxymethylsilane; dihydrogensilane compounds such as dimethoxysilane, diethoxysilane, methoxymethylsilane, and ethoxymethylsilane; trihydrogensilane compounds such as methoxysilane and ethoxysilane; and chlorohydrogensilane compounds such as trichlorosilane, dichloromethylsilane, and chlorodimethylsilane. These may be used individually or in combination of two or more. Among these, when using compound (3) obtained by the hydrosilylation reaction described later as a silane coupling agent or resin additive, trimethoxysilane, triethoxysilane, dimethoxymethylsilane, diethoxymethylsilane, dimethoxysilane, and diethoxysilane are preferred from the viewpoint of reacting with multiple hydroxyl groups on the substrate surface to improve adhesion.

[0022] In general formula (2), R 3 R represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and a specific example thereof is R 1 Examples of substituents similar to those exemplified in [reference] include the monovalent hydrocarbon group.

[0023] In general formula (2), R 4 This represents an unsubstituted divalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 8 carbon atoms. R 4 The divalent hydrocarbon group may be linear, branched, or cyclic. Specific examples include linear alkylene groups such as methylene, ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, and octamethylene; branched alkylene groups such as sec-propylene, sec-butylene, tert-butylene, sec-pentylene, tert-pentylene, sec-hexylene, tert-hexylene, sec-heptylene, tert-heptylene, sec-octylene, and tert-octylene; and cyclic alkylene groups such as cyclopropylene, cyclopentylene, and cyclohexylene.

[0024] Among these, R 4 As such, unsubstituted linear alkylene groups having 1 to 6 carbon atoms are preferred, and in particular, from the viewpoint of the availability of precursor raw materials, unsubstituted linear alkylene groups having 1 to 4 carbon atoms, such as methylene groups and ethylene groups, are more preferred.

[0025] Specific examples of compound (2) include allyl acetoacetate, butenyl acetoacetate, hexenyl acetoacetate, octenyl acetoacetate, allyl propionyl acetate, butenyl propionyl acetate, hexenyl propionyl acetate, octenyl propionyl acetate, allyl butyryl acetate, butenyl butyryl acetate, hexenyl butyryl acetate, octenyl butyryl acetate, etc. These may be used individually or in combination of two or more. Among these, allyl acetoacetate, butenyl acetoacetate, hexenyl acetoacetate, and octenyl acetoacetate are particularly preferred from the viewpoint of the availability of precursor raw materials.

[0026] In the manufacturing method of the present invention, the mixing ratio of compound (1) and compound (2) is not particularly limited, but from the viewpoint of reactivity and productivity, it is preferably in the range of 1 to 20 moles, more preferably 1 to 10 moles, and even more preferably 1 to 5 moles of compound (1) per mole of compound (2).

[0027] In the manufacturing method of the present invention, examples of ketone solvents include acetone, diacetone alcohol, diethyl ketone, methyl ethyl ketone, methyl isobutyl ketone, methyl n-butyl ketone, dibutyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, and cyclooctanone. These may be used individually or in combination of two or more. Among these, acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclopentanone, and cyclohexanone are preferred, particularly from the viewpoint of increasing the ratio of keto-form chemical species to enol-form chemical species of compound (2).

[0028] The amount of ketone solvent used is not particularly limited as long as it increases the ratio of keto-form chemical species to enol-form chemical species of compound (2), but from the viewpoint of productivity, it is preferably in the range of 10 to 200% by mass, more preferably 30 to 150% by mass, and even more preferably 50 to 100% by mass relative to compound (2).

[0029] As the platinum catalyst, it can be appropriately selected and used from known platinum (Pt) and complex compounds with platinum as the central metal. Specific examples include alcoholic solutions of chloroplatinic acid, such as chloroplatinic acid and chloroplatinic acid(IV) in 2-ethylhexanol solution; toluene or xylene solution of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex; dichlorobisacetonitrile platinum; dichlorobisbenzonitrile platinum; and dichlorocyclooctadiene platinum. Catalysts in which platinum black or similar materials are supported on a carrier such as alumina, silica, or carbon can also be used. These can be used individually or in combination of two or more. Among these, as platinum catalysts, alcoholic solutions of chloroplatinic acid, such as a 2-ethylhexanol solution of chloroplatin(IV) acid, and toluene or xylene solutions of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex are preferred, particularly from the viewpoint of high reactivity.

[0030] The amount of platinum catalyst used is not particularly limited as long as it is an amount that exhibits the catalytic effect of the hydrosilylation reaction. However, from the viewpoint of reactivity and productivity, the amount of platinum metal used is preferably in the range of 0.0000001 to 1 mole, more preferably 0.000001 to 0.1 moles, and even more preferably 0.00001 to 0.01 moles per mole of compound (2).

[0031] The reaction temperature for the above hydrosilylation reaction is not particularly limited, but from the viewpoint of reactivity and productivity, it is preferably 50 to 200°C, more preferably 50 to 150°C, and even more preferably 50 to 120°C. The reaction time is also not particularly limited, but is preferably 1 to 30 hours, more preferably 1 to 20 hours, and even more preferably 1 to 10 hours.

[0032] In general formula (3), R 1 , R 2 , R 3 , R 4 And n have the same meaning as in general formulas (1) and (2).

[0033] Specific examples of compound (3) include 3-trimethoxysilylpropyl acetacetate, 3-dimethoxymethylsilylpropyl acetacetate, 3-triethoxysilylpropyl acetacetate, 3-diethoxymethylsilylpropyl acetacetate, 3-trimethoxysilylbutyl acetacetate, 3-dimethoxymethylsilylbutyl acetacetate, 3-triethoxysilylbutyl acetacetate, 3-diethoxymethylsilylbutyl acetacetate, 3-trimethoxysilylhexyl acetacetate, and 3-dimethoxymethyl Silylhexyl acetate, 3-triethoxysilylhexyl acetate, 3-diethoxymethylsilylhexyl acetate, 3-trimethoxysilyloctyl acetate, 3-dimethoxymethylsilyloctyl acetate, 3-triethoxysilyloctyl acetate, 3-diethoxymethylsilyloctyl acetate, 3-trimethoxysilylpropylpropionyl acetate, 3-dimethoxymethylsilylpropylpropionyl acetate, 3-triethoxysilylpropylpropionyl acetate 3-Diethoxymethylsilylpropylpropionyl acetate, 3-Trimethoxysilylbutylpropionyl acetate, 3-Dimethoxymethylsilylbutylpropionyl acetate, 3-Triethoxysilylbutylpropionyl acetate, 3-Diethoxymethylsilylbutylpropionyl acetate, 3-Trimethoxysilylhexylpropionyl acetate, 3-Dimethoxymethylsilylhexylpropionyl acetate, 3-Triethoxysilylhexylpropionyl acetate, 3-Diethoxymethylsilylhexylpropionyl Acetate, 3-trimethoxysilyloctylpropionyl acetate, 3-dimethoxymethylsilyloctylpropionyl acetate, 3-triethoxysilyloctylpropionyl acetate, 3-diethoxymethylsilyloctylpropionyl acetate, 3-trimethoxysilylpropylbutyryl acetate, 3-dimethoxymethylsilylpropylbutyryl acetate, 3-triethoxysilylpropylbutyryl acetate, 3-diethoxymethylsilylpropylbutyryl acetate, 3-trimethoxysilylbutylbutyryl acetate,Examples include 3-dimethoxymethylsilylbutylbutyryl acetate, 3-triethoxysilylbutylbutyryl acetate, 3-diethoxymethylsilylbutylbutyryl acetate, 3-trimethoxysilylhexylbutyryl acetate, 3-dimethoxymethylsilylhexylbutyryl acetate, 3-triethoxysilylhexylbutyryl acetate, 3-diethoxymethylsilylhexylbutyryl acetate, 3-trimethoxysilyloctylbutyryl acetate, 3-dimethoxymethylsilyloctylbutyryl acetate, 3-triethoxysilyloctylbutyryl acetate, and 3-diethoxymethylsilyloctylbutyryl acetate.

[0034] Among these, particularly from the viewpoint of the ease of obtaining precursor raw materials, 3-trimethoxysilylpropyl acetacetate, 3-dimethoxymethylsilylpropyl acetacetate, 3-triethoxysilylpropyl acetacetate, 3-diethoxymethylsilylpropyl acetacetate, 3-trimethoxysilylbutyl acetacetate, 3-dimethoxymethylsilylbutyl acetacetate, 3-triethoxysilylbutyl acetacetate, 3-diethoxymethylsilylbutyl Acetoacetate, 3-trimethoxysilylhexylacetate, 3-dimethoxymethylsilylhexylacetate, 3-triethoxysilylhexylacetate, 3-diethoxymethylsilylhexylacetate, 3-trimethoxysilyloctylacetate, 3-dimethoxymethylsilyloctylacetate, 3-triethoxysilyloctylacetate, and 3-diethoxymethylsilyloctylacetate are preferred. [Examples]

[0035] The present invention will be described more specifically below with reference to examples and comparative examples, but the present invention is not limited to the following examples. The purity of the following β-ketoester structure-containing organosilicon compounds was measured using the following gas chromatography measurement condition 1. [Gas chromatography measurement conditions 1] Gas chromatograph: GC-2014 (manufactured by Shimadzu Corporation) Packed column: Silicone SE-30 (manufactured by GL Sciences Co., Ltd.) Detector: TCD Detector temperature: 300℃ Inlet temperature: 200℃ Temperature increase program: 70°C (0 min) → 10°C / min → 300°C (10 min) Carrier gas: Helium (50 ml / min) Injection volume: 1μl

[0036] [Example 1] Synthesis of 3-trimethoxysilylpropylacetoacetate In a flask equipped with a stirrer, refluxer, dropping funnel, and thermometer, 142.2 g (1,000 mol) of allyl acetoacetate, 142.2 g of acetone, and a toluene solution of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (0.00002 mol as platinum atoms) were charged at room temperature and heated over 0.5 hours until the temperature reached 55°C. After the internal temperature stabilized, 122.2 g (1,000 mol) of trimethoxysilane was added dropwise over 5 hours at 50-60°C, and the mixture was stirred at that temperature for 1 hour. The resulting reaction mixture was a homogeneous, pale yellow, transparent liquid. This mixture was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding acetone. The results are shown in Table 2.

[0037] [Example 2] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that 71.1 g of acetone was used instead. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding acetone. The results are shown in Table 2.

[0038] [Example 3] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that 42.6 g of acetone was used instead. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding acetone. The results are shown in Table 2.

[0039] [Example 4] Synthesis of 3-trimethoxysilylpropylacetate The reaction was carried out in the same manner as in Example 1, except that 14.2 g of acetone was used instead. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding acetone. The results are shown in Table 2.

[0040] [Example 5] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that the reaction temperature was changed to 60-70°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding acetone. The results are shown in Table 2.

[0041] [Example 6] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that acetone was replaced with methyl ethyl ketone. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding methyl ethyl ketone. The results are shown in Table 2.

[0042] [Example 7] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that acetone was replaced with methyl isobutyl ketone. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding methyl isobutyl ketone. The results are shown in Table 2.

[0043] [Example 8] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that acetone was replaced with diisobutyl ketone. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding the diisobutyl ketone. The results are shown in Table 2.

[0044] [Example 9] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that acetone was replaced with cyclopentanone. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding cyclopentanone. The results are shown in Table 2.

[0045] [Example 10] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 1, except that acetone was replaced with cyclohexanone. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding cyclohexanone. The results are shown in Table 2.

[0046] [Example 11] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 7, except that the reaction temperature was changed to 70-80°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding methyl isobutyl ketone. The results are shown in Table 2.

[0047] [Example 12] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Example 7, except that the reaction temperature was changed to 100-110°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding methyl isobutyl ketone. The results are shown in Table 2.

[0048] [Comparative Example 1] Synthesis of 3-trimethoxysilylpropylacetate The reaction was carried out in the same manner as in Example 1, except that acetone was not used. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture. The results are shown in Table 2.

[0049] [Comparative Example 2] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Comparative Example 1, except that the reaction temperature was changed to 70-80°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the ratio of the area percentage of the reaction mixture. The results are shown in Table 2.

[0050] [Comparative Example 3] Synthesis of 3-trimethoxysilylpropylacetate The reaction was carried out in the same manner as in Comparative Example 1, except that the reaction temperature was changed to 100-110°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the ratio of the area percentage of the reaction mixture. The results are shown in Table 2.

[0051] [Comparative Example 4] Synthesis of 3-trimethoxysilylpropylacetate The reaction was carried out in the same manner as in Comparative Example 2, except that N,N-dimethylformamide was used. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding N,N-dimethylformamide. The results are shown in Table 2.

[0052] [Comparative Example 5] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Comparative Example 2, except that dimethyl sulfoxide was used. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding dimethyl sulfoxide. The results are shown in Table 2.

[0053] [Comparative Example 6] Synthesis of 3-trimethoxysilylpropylacetoacetate The reaction was carried out in the same manner as in Comparative Example 2, except that n-hexane was used. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to determine the area percentage ratio of the reaction mixture excluding n-hexane. The results are shown in Table 2.

[0054] Table 1 summarizes the reaction conditions for the above examples and comparative examples.

[0055] [Table 1]

[0056] [Table 2]

[0057] In Table 2, A1 to F1 represent the following compounds, and "%" represents "area %". A1 = Trimethoxysilane B1 = Tetramethoxysilane C1 = Methyl acetoacetate D1 = Allyl acetoacetate E1 = 1,1-dimethoxy-2-oxa-1-silacyclopentane F1 = 3-trimethoxysilylpropylacetoacetate (target substance)

[0058] As shown in Table 2, in Examples 1 to 12, the reactivity of the main reaction, the hydrosilylation reaction, increased in the presence of a ketone solvent, as the proportion of keto species, which are tautomers of the β-ketoester compound, increased. In other words, there was less unreacted trimethoxysilane and allyl acetoacetate, and the yield of the target product improved. Furthermore, even under conditions where the reaction temperature is below 60°C, the amount of tetramethoxysilane is low, and it can be seen that disproportionation reactions (side reaction 2), transesterification reactions (side reaction 3), and dehydrogenation reactions (side reaction 4) are suppressed. Furthermore, even under conditions where the reaction temperature is 100°C or higher, the amount of 1,1-dimethoxy-2-oxa-1-silacyclopentane is low, indicating that the thermal decomposition reaction (side reaction 1) is suppressed.

[0059] On the other hand, in Comparative Examples 1-3, when a ketone solvent is absent, the proportion of enol species increases, resulting in a large amount of unreacted trimethoxysilane and allyl acetoacetate. This leads to disproportionation (side reaction 2), transesterification (side reaction 3), and dehydrogenation (side reaction 4), which reduce the yield of the target product. Furthermore, increasing the reaction temperature to complete the reaction promotes thermal decomposition (side reaction 1), which also reduces the yield of the target product. In Comparative Examples 4-6, the yield of the target product was lower than in Example 12, which was carried out at the same reaction temperature, when solvents other than ketone solvents were used. This indicates that these solvents do not have the effect of suppressing multiple side reactions.

Claims

1. The following general formula (1) 【Chemistry 1】 (In the formula, R 1 Each of these independently represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, R 2 Each of these independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, and n is an integer from 0 to 2. Hydrogensilane compounds shown, The following general formula (2) 【Chemistry 2】 (In the formula, R 3 R represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. 4 (This represents an unsubstituted divalent hydrocarbon group with 1 to 20 carbon atoms.) The following general formula (3) is characterized by the hydrosilylation reaction of a β-ketoester compound having an unsaturated bond represented by the formula, using a platinum catalyst in the presence of a ketone solvent. 【Transformation 3】 (In the formula, R 1 , R 2 , R 3 , R 4 (And n have the same meaning as above.) A method for producing organosilicon compounds containing a β-ketoester structure as shown.

2. The method for producing a β-ketoester structure-containing organosilicon compound according to claim 1, wherein the ketone solvent is one or more selected from acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclopentanone, and cyclohexanone.

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