Method for producing β-ketoester structure-containing organosilicon compound

Abstract

By this method for producing a compound represented by general formula (3) (wherein R1, R2, R3, R4, and n are as defined below), in which a hydrogen silane compound represented by general formula (1) (wherein each R1 independently represents a hydrogen atom, a halogen atom, or a monovalent hydrocarbon group having 1 to 20 carbon atoms, each R2 independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and n represents an integer of 0 to 2) and a β-ketoester compound having an unsaturated bond and represented by general formula (2) (wherein R3 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms and R4 represents an unsubstituted divalent hydrocarbon group having 1 to 20 carbon atoms) are caused to undergo a hydrosilylation reaction in the presence of a ketone solvent using a platinum catalyst, a plurality of side reactions can be suppressed while enhancing the reactivity of the hydrosilylation reaction that is the main reaction, and a target product can be produced with a high yield.

Description

Method for producing organosilicon compounds containing β-ketoester structure

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

[0002] Organosilicon compounds, which contain both a hydrolyzable silyl group and an organic group, enable the bonding of organic and inorganic materials that would normally be difficult to bond. This is 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. As a result, organic-inorganic composite materials can be given properties such as heat resistance, water resistance, weather resistance, improved mechanical strength, adhesion, dispersibility, hydrophobicity, and corrosion resistance. Utilizing these properties, the above-mentioned organosilicon compounds 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. An example of such an organosilicon compound having a β-ketoester structure is 3-trimethoxysilylpropylacetoacetate (Patent Document 1).

[0004] Japanese Patent Publication No. 2005-314325

[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]

[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. Specifically, in the disproportionation reaction, a by-product is generated in which the hydrogen atoms and alkoxy groups of the hydrogen silane compound are mutually converted. In the transesterification reaction, a by-product is generated 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]

[0009] Therefore, in the hydrosilylation reaction of a hydrogensilane compound and 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 aims to provide a method for producing organosilicon compounds containing a β-ketoester structure in high yield by suppressing multiple side reactions while increasing the reactivity of the main hydrosilylation reaction in the hydrosilylation reaction of a hydrogensilane compound and a β-ketoester compound having an unsaturated bond.

[0011] The inventors diligently conducted research to achieve the above objectives and discovered that by hydrosilylation reacting a hydrogen silane compound and a β-ketoester compound having an unsaturated bond with a platinum catalyst in the presence of a ketone solvent, the reactivity of the main hydrosilylation reaction is enhanced while suppressing multiple side reactions, thereby producing a β-ketoester structure-containing organosilicon compound in high yield, thus completing the invention.

[0012] In other words, the present invention relates to: 1. The following general formula (1) (In the formula, R 1Each 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 represented by the following general formula (2) (In the formula, R 3 R represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms. 4 The following general formula (3) is characterized by hydrosilylation of a β-ketoester compound having an unsaturated bond represented by (), using a platinum catalyst in the presence of a ketone solvent. (In the formula, R 1 , R 2 , R 3 , R 4 1. A method for producing an organosilicon compound containing a β-ketoester structure, represented by (where n and n have the same meaning as above). 2. A method for producing an organosilicon compound containing a β-ketoester structure, wherein the ketone solvent is one or more selected from acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclopentanone, and cyclohexanone.

[0013] According to the method for producing β-ketoester structure-containing organosilicon compounds of the present invention, 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 of the β-ketoester compound used as a starting material becomes high, and the reactivity of the main reaction, hydrosilylation, is increased. As a result, multiple side reactions are suppressed, and the target product can be produced in high yield.

[0014] The present invention will be described in detail below. In the present 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]

[0016] In general formula (1), R 1 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 R 1 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The monovalent hydrocarbon group of R 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, etc.

[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 groups; cyano groups; amino groups; ester groups; ether groups; carbonyl groups; acyl groups; sulfide groups, etc. One or more of these can be used in combination. The substitution position of these substituents is not particularly limited, nor is the number of substituents 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 from 0 to 2, but 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 compound (3) obtained by the hydrosilylation reaction described later is used 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 R 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. 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, and octenyl butyryl acetate. 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 particularly preferred 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 having platinum as the central metal. Specific examples thereof include alcohol solutions of chloroplatinic acid such as 2-ethylhexanol solution of chloroplatinic acid and chloroplatinic (IV) acid; toluene or xylene solutions of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex; dichlorobisacetonitrile platinum, dichlorobisbenzonitrile platinum; dichlorocyclooctadiene platinum and the like. Further, a catalyst in which platinum black or the like is supported on a carrier such as alumina, silica, carbon or the like can also be used. These may be used alone or in combination of two or more. Among these, as the platinum catalyst, from the viewpoint of particularly high reactivity, an alcohol solution of chloroplatinic acid such as 2-ethylhexanol solution of chloroplatinic (IV) acid and a toluene or xylene solution of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex are preferred.

[0030] The amount of the platinum catalyst used is not particularly limited as long as the catalytic effect of the hydrosilylation reaction is exhibited. However, from the viewpoints of reactivity and productivity, based on 1 mol of the compound (2), as platinum metal, it is preferably in the range of 0.0000001 to 1 mol, more preferably 0.000001 to 0.1 mol, and even more preferably 0.00001 to 0.01 mol.

[0031] The reaction temperature of the above hydrosilylation reaction is not particularly limited. However, from the viewpoints 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 not particularly limited either, but it is preferably 1 to 30 hours, more preferably 1 to 20 hours, and even more preferably 1 to 10 hours.

[0032] In the general formula (3), R 1 , R 2 , R 3 , R 4 and n represent the same meanings as in the 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,3-dimethoxymethylsilylbutyl butyryl acetate, 3-triethoxysilylbutyl butyryl acetate, 3-diethoxymethylsilylbutyl butyryl acetate, 3-trimethoxysilylhexyl butyryl acetate, 3-dimethoxymethylsilylhexyl butyryl acetate, 3-triethoxysilylhexyl butyryl acetate, 3-diethoxymethylsilylhexyl butyryl acetate, 3-trimethoxysilyloctyl butyryl acetate, 3-dimethoxymethylsilyloctyl butyryl acetate, 3-triethoxysilyloctyl butyryl acetate, 3-diethoxymethylsilyloctyl butyryl acetate and the like can be mentioned.

[0034] Among these, from the viewpoint of the availability of the starting materials, 3-trimethoxysilylpropyl acetoacetate, 3-dimethoxymethylsilylpropyl acetoacetate, 3-triethoxysilylpropyl acetoacetate, 3-diethoxymethylsilylpropyl acetoacetate, 3-trimethoxysilylbutyl acetoacetate, 3-dimethoxymethylsilylbutyl acetoacetate, 3-triethoxysilylbutyl acetoacetate, 3-diethoxymethylsilylbutyl acetoacetate, 3-trimethoxysilylhexyl acetoacetate, 3-dimethoxymethylsilylhexyl acetoacetate, 3-triethoxysilylhexyl acetoacetate, 3-diethoxymethylsilylhexyl acetoacetate, 3-trimethoxysilyloctyl acetoacetate, 3-dimethoxymethylsilyloctyl acetoacetate, 3-triethoxysilyloctyl acetoacetate, 3-diethoxymethylsilyloctyl acetoacetate are preferred.

[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 is the value measured under the following gas chromatography measurement conditions 1. [Gas chromatography measurement conditions 1] Gas chromatograph: GC-2014 (Shimadzu Corporation) Packed column: Silicone SE-30 (GL Sciences Co., Ltd.) Detector: TCD Detector temperature: 300℃ Injection port temperature: 200℃ Heating program: 70℃ (0 min) → 10℃ / min → 300℃ (10 min) Carrier gas: Helium (50 ml / min) Injection volume: 1 μl

[0036] [Example 1] Synthesis of 3-trimethoxysilylpropyl acetoacetate 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 stirred at that temperature for 1 hour. 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.

[0037] [Example 2] Synthesis of 3-trimethoxysilylpropylacetate: 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-trimethoxysilylpropylacetate: 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] The reaction was carried out in the same manner as in Example 1, except that 14.2 g of acetone was used to synthesize 3-trimethoxysilylpropylacetate. 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] The reaction was carried out in the same manner as in Example 1, except that the reaction temperature for the synthesis of 3-trimethoxysilylpropylacetate was changed to 60-70°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to confirm the area percentage ratio of the reaction mixture excluding acetone. The results are shown in Table 2.

[0041] [Example 6] Synthesis of 3-trimethoxysilylpropyl acetate 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-trimethoxysilylpropyl acetate 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-trimethoxysilylpropyl acetate 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 diisobutyl ketone. The results are shown in Table 2.

[0044] [Example 9] Synthesis of 3-trimethoxysilylpropyl acetate 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-trimethoxysilylpropyl acetate 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] The reaction was carried out in the same manner as in Example 7, except that the reaction temperature for the synthesis of 3-trimethoxysilylpropyl acetacetate was changed to 70-80°C. The resulting reaction mixture was a homogeneous pale yellow transparent liquid, which was analyzed by gas chromatography to confirm the area percentage ratio of the reaction mixture excluding methyl isobutyl ketone. The results are shown in Table 2.

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

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

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

[0052] [Comparative Example 5] The reaction was carried out in the same manner as in Comparative Example 2, except that a synthetic dimethyl sulfoxide of 3-trimethoxysilylpropyl acetacetate 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 the dimethyl sulfoxide. The results are shown in Table 2.

[0053] [Comparative Example 6] Synthesis of 3-trimethoxysilylpropylacetate 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 confirm 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]

[0056]

[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 product)

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

[0059] On the other hand, in Comparative Examples 1 to 3, when a ketone solvent is absent, the proportion of enol-type chemical 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 to 6, when solvents other than ketone solvents are used, the yield of the target product is lower than in Example 12, which was reacted at the same reaction temperature. This indicates that these solvents do not have the effect of suppressing multiple side reactions.

Claims

1. The following general formula (1) (In the formula, R 1 each independently represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, and R 2 each independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, and n is an integer of 0 to 2.) A hydrogen silane compound represented by the following general formula (2) (In the formula, R 3 represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, and R 4 represents an unsubstituted divalent hydrocarbon group having 1 to 20 carbon atoms.) A β-ketoester compound having an unsaturated bond represented by the following general formula (3) is subjected to a hydrosilylation reaction using a platinum catalyst in the presence of a ketone solvent. (In the formula, R 1 , R 2 , R 3 , R 4 and n represent the same meaning as described above.) A method for producing a β-ketoester structure-containing organosilicon compound represented by the following general formula (3).

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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