Method for producing alkoxymonosilane compounds

Abstract

This invention provides a novel method for producing alkoxymonosilane compounds that does not require high pressure and high temperature conditions, nor does it require the use of strong basic reagents such as potassium hydroxide. [Solution] The present invention provides a method for producing an alkoxymonosilane compound, comprising step (S1) of contacting an organopolysiloxane compound (A) with an alcohol containing an alkoxide generated by an electrochemical method in an electrolytic cell containing an alcohol containing a supporting electrolyte.

Description

[Technical Field]

[0001] This invention relates to a method for producing alkoxymonosilane compounds. [Background technology]

[0002] Conventionally, a known method for producing tetraalkoxysilanes from a silicon source involves reacting silicon, silicon alloys, or mixtures thereof with an alcohol in the presence of an alkaline catalyst. For example, Patent Document 1 proposes carrying out this reaction under pressure and reflux, with an evaporation rate of 0.2 L / L·Hr or higher. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2001-302676 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, the manufacturing method described in Patent Document 1 involves applying a pressure of 2 × 10⁻⁶ 5 ~8×10 5 The current method involves setting the pressure to Pa and the temperature to 120-200°C, making it essential to carry out the process under high pressure and high temperature conditions. From the perspective of producing alkoxymonosilane compounds, such as tetraalkoxysilanes, more simply and easily, it is desirable to establish a novel method for producing alkoxymonosilane compounds that does not require the above-mentioned high pressure and high temperature conditions. Furthermore, while Patent Document 1 requires the use of strong basic reagents such as potassium hydroxide, it is desirable to establish a novel method for producing alkoxymonosilane compounds that does not require the use of such strong basic reagents, from the standpoint of safety and the complexity of wastewater treatment.

[0005] An object of the present invention is to provide a novel method for producing an alkoxymonosilane compound that does not require implementation under high-pressure and high-temperature conditions and does not require the use of a strong base reagent such as potassium hydroxide.

Means for Solving the Problems

[0006] According to the present invention, the following [1] to [5] are provided. [1] A method for producing an alkoxymonosilane compound, comprising a step (S1) of contacting the alcohol containing an alkoxide generated by an electrochemical method with an organopolysiloxane compound (A) in an electrolytic cell containing an alcohol containing a supporting electrolyte. [2] The method for producing an alkoxymonosilane compound according to claim 1, wherein a dehydrating agent is added to the alcohol in the electrolytic cell. [3] The method for producing an alkoxymonosilane compound according to [1] or [2] above, wherein the organopolysiloxane compound (A) is at least one selected from the group consisting of a chain organopolysiloxane compound (A1) represented by the following general formula (a1) and a cyclic organopolysiloxane compound (A2) represented by the following general formula (a2).

Chemical formula

[0007] According to the present invention, it is possible to provide a novel method for producing alkoxymonosilane compounds that does not require the use of strong base reagents such as potassium hydroxide, nor does it require the use of high pressure and high temperature conditions. [Modes for carrying out the invention]

[0008] The upper and lower limits of the numerical ranges described herein can be combined in any way. For example, if the numerical ranges "A to B" and "C to D" are described, the numerical ranges "A to D" and "C to B" are also included within the scope of the present invention. Furthermore, unless otherwise specified, the numerical range "lower limit to upper limit" described herein means that the value is greater than or equal to the lower limit and less than or equal to the upper limit. Furthermore, in this specification, the numerical values ​​in the examples are values ​​that can be used as upper or lower limits.

[0009] In this specification, "room temperature" means a temperature without intentional cooling or heating, i.e., normal temperature. Specifically, for example, this is 15 to 35°C.

[0010] In this specification, "normal pressure" means the pressure without intentional pressurization or depressurization, i.e., normal atmospheric pressure. Specifically, for example, 0.5 × 10⁻⁶5 ~1.5×10 5 Pa (preferably 1.0 × 10) 5 Pa)

[0011] [Method for producing alkoxymonosilane compounds] The method for producing the alkoxymonosilane compound of this embodiment includes a step (S1) of contacting an organopolysiloxane compound (A) with an alcohol containing an alkoxide generated by an electrochemical method in an electrolytic cell containing an alcohol containing a supporting electrolyte. The inventors of the present invention conducted diligent research to solve the above problems. As a result, they discovered that by reacting an alcohol-derived alkoxide, generated by electrochemical means in an alcohol containing a supporting electrolyte, with an organopolysiloxane compound (A), it is possible to produce an alkoxymonosilane compound at room temperature and atmospheric pressure, without requiring the use of high pressure and high temperature conditions, nor without requiring the use of strong base reagents such as potassium hydroxide. Based on these findings, the inventors conducted further studies and completed the present invention. The method for producing the alkoxymonosilane compound of this embodiment will be described in detail below.

[0012] <Process (S1)> In the method for producing the alkoxymonosilane compound of this embodiment, step (S1) requires generating an alkoxide derived from an alcohol containing a supporting electrolyte by an electrochemical method. Then, by contacting the alcohol containing the alkoxide generated by the electrochemical method with the organopolysiloxane compound (A), the alkoxide and the organopolysiloxane compound (A) react to produce the alkoxymonosilane compound. In other words, in this embodiment, the alkoxide generated by the electrochemical method functions as a trigger for producing the alkoxymonosilane compound from the organopolysiloxane compound (A). This makes it possible to produce the alkoxymonosilane compound without requiring the process to be carried out under high pressure and high temperature conditions.

[0013] (Electrochemical methods) The electrochemical method is carried out in an electrolytic cell equipped with electrodes. The electrolytic cell is equipped with, for example, at least two electrodes: a working electrode and a counter electrode. The electrolytic cell may be an integrated electrolytic cell in which the two electrodes are installed in the same cell, or it may be a separate electrolytic cell (for example, an H-type electrolytic cell) in which the two electrodes are installed in separate cells. Here, the electrochemical method is not limited to a method using two electrodes, a working electrode and a counter electrode, but may also be a three-electrode method using a reference electrode.

[0014] Examples of electrodes for the working electrode and counter electrode include carbon-based materials such as amorphous carbon, graphite, carbon fiber, glassy carbon, composites of carbon fiber and glassy carbon, RVC (reticulated vitreous carbon), and boron-doped diamond; metallic materials such as stainless steel, nickel, tungsten, niobium, copper, and titanium; precious metal materials such as platinum, gold, and palladium; alloy steels such as stainless steel and lead bronze; and oxide materials such as ITO (indium tin oxide) and FTO (fluorine-doped tin oxide). When using a reference electrode, examples of reference electrodes include reversible hydrogen electrodes (RHE), silver-silver chloride electrodes (Ag / AgCl), and Ag / Ag + Electrodes (e.g., silver-silver nitrate (Ag / Ag) + Examples include calomel electrodes (SCE) and palladium-hydrogen electrodes (Pd / H2).

[0015] The electrochemical method is carried out after at least the supporting electrolyte and alcohol are placed in the electrolytic cell. By placing the supporting electrolyte together with the alcohol in the electrolytic cell, the alcohol containing the supporting electrolyte functions as an electrolyte, and by applying a voltage to the electrolyte, an electrochemical reaction proceeds, generating an alkoxide derived from the alcohol. Then, by contacting the alcohol containing the alkoxide with an organopolysiloxane compound (A), the alkoxide and the organopolysiloxane compound (A) react to produce an alkoxymonosilane compound. There are no particular restrictions on the timing of adding the organopolysiloxane compound (A) to the electrolytic cell. The organopolysiloxane compound (A) may be added to the electrolytic cell along with the supporting electrolyte and alcohol, and then the electrochemical method may be carried out. Alternatively, the organopolysiloxane compound (A) may be added to the electrolytic cell after generating an alkoxide by the electrochemical method. Of course, these methods may also be used in combination. In addition, substances other than the supporting electrolyte, alcohol, and organopolysiloxane compound (A) may be introduced into the electrolytic cell. Examples of such substances include buffering agents.

[0016] (supporting electrolyte) Support electrolytes are used to ensure the conductivity of the electrolyte solution. As the supporting electrolyte, salts and other combinations of cations and anions can be used without any particular restrictions. Examples of cations include tetraalkylammonium compounds such as tetramethylammonium, tetraethylammonium, and tetrabutylammonium (the number of carbon atoms in the alkyl group is preferably 1 to 4, and alkyl groups with different numbers of carbon atoms may be combined); alkali metal ions such as lithium ions, sodium ions, and potassium ions; oxonium; and carbonium. Examples of anions include hydroxide ions; halide ions such as fluoride ions, chloride ions, bromide ions, and iodide ions; sulfonates; phosphonates; hexafluorophosphates; tosylates; nitrates; borates such as tetrafluoroborate, tetraphenylborate, and tetraquispentafluorophenylborate; and perchlorates. Specific examples of compounds include tetramethylammonium tosylate, tetraethylammonium tosylate, tetrabutylammonium tosylate, lithium tosylate, sodium tosylate, potassium tosylate, tetramethylammonium tetrafluoroborate, tetraethylammonium tetrafluoroborate, tetrabutylammonium tetrafluoroborate, lithium tetrafluoroborate, sodium tetrafluoroborate, potassium tetrafluoroborate, tetramethylammonium tetraphenylborate, tetraethylammonium tetraphenylborate, tetrabutylammonium tetraphenylborate, lithium tetraphenylborate, sodium tetraphenylborate, potassium tetraphenylborate, tetramethylammonium tetrakispentafluorophenylborate, tetraethylammonium tetrakispentafluorophenylborate, tetrabutylammonium tetrakispentafluorophenylborate, lithium tetrakispentafluorophenylborate, sodium tetrakispentafluorophenylborate, potassium tetrakispentafluorophenylborate, tetramethylammonium perchlorate, tetraethylammonium perchlorate, tetrabutylammonium perchlorate, lithium perchlorate, sodium perchlorate, potassium perchlorate, and the like. Among these, tetrabutylammonium tetrafluoroborate, lithium perchlorate, and tetrabutylammonium perchlorate are preferred from the viewpoint of improving the yield of alkoxymonosilane compounds, and tetra-n-butylammonium perchlorate is more preferred. The supporting electrolyte may be used alone or in combination of two or more types.

[0017] (alcohol) Alcohols are used as a source of alkoxides, as well as as a solvent for forming electrolytes. As the alcohol, various alcohols that can generate alkoxides by electrochemical methods can be used without particular limitation. However, from the viewpoint of ease of production of the alkoxymonosilane compound, availability and handling, the number of carbon atoms in the alcohol is preferably 1 to 21, more preferably 1 to 12, even more preferably 1 to 6, even more preferably 1 to 4, still still preferably 1 to 3, even more preferably 1 to 2, and even more preferably 1. The hydrocarbon group present in the alcohol is preferably an alkyl group. The alkyl group may be a linear alkyl group, a branched alkyl group, or a cyclic alkyl group. If the alkyl group is a cyclic alkyl group, the number of carbon atoms is preferably 3 to 6, more preferably 4 to 6, and even more preferably 5 to 6. The preferred alkyl group is either a linear alkyl group or a branched alkyl group. Furthermore, the alcohol may be a monohydric alcohol having one hydroxyl group, or a polyhydric alcohol having two or more hydroxyl groups, but from the viewpoint of ease of production of the alkoxymonosilane compound, availability, and handling, a monohydric alcohol is preferred.

[0018] Preferred alcohols include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, iso-butanol, tert-butanol, n-pentanol, iso-pentanol, neopentyl alcohol, n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol, n-undecanol, n-dodecanol, n-tridecanol, n-tetradecanol, n-pentadecanol, n-hexadecanol, n-heptadecanol, n-octadecanol, n-nonadecanol, cyclopentanol, and cyclohexanol. Among these, methanol and ethanol are preferred, with methanol being more preferred.

[0019] Here, from the viewpoint of the usefulness of the final product, the alkoxymonosilane compound, it is preferable that the number of carbon atoms in the alcohol is the same as the number of carbon atoms in the alkoxy group of the chain-like organopolysiloxane compound (A1) and the cyclic organopolysiloxane compound (A2) described later.

[0020] Alcohol may be used alone or in combination of two or more types.

[0021] (Polyorganosiloxane compound (A)) Polyorganosiloxane compound (A) is a compound that serves as a starting material for the final product, an alkoxymonosilane compound, and has a repeating -Si-O- unit in its main chain and a hydrocarbon group or an oxygen-containing hydrocarbon group in its side chain. The polyorganosiloxane compound (A) used in this embodiment is not particularly limited, but preferably one or more selected from the group consisting of a linear organopolysiloxane compound (A1) represented by the following general formula (a1) and a cyclic organopolysiloxane compound (A2) represented by the following general formula (a2).

[0022] [ka]

[0023] In the above general formulas (a1) and (a2), R 1 ~R 8 and R 11 ~R 16 Each of these is independently an alkyl group having 1 to 21 carbon atoms or an alkoxy group having 1 to 21 carbon atoms. n is an integer from 0 to 4. m is an integer from 0 to 4.

[0024] R 1 ~R 8 and R 11 ~R 16The number of carbon atoms in the alkyl or alkoxy group that can be selected is preferably 1 to 21, more preferably 1 to 12, even more preferably 1 to 6, even more preferably 1 to 4, still more preferably 1 to 3, even more preferably 1 to 2, and even more preferably 1, from the viewpoint of ease of production of the alkoxymonosilane compound, availability and handling. R 1 ~R 8 and R 11 ~R 16 The alkyl group that can be selected as the alkyl group or alkoxy group may be a linear alkyl group, a branched alkyl group, or a cyclic alkyl group. If the alkyl group is a cyclic alkyl group, the number of carbon atoms is preferably 3 to 6, more preferably 4 to 6, and even more preferably 5 to 6.

[0025] R 1 ~R 8 and R 11 ~R 16 Specific examples of alkyl groups that can be selected as alkyl groups or alkoxy groups include alkyl groups such as methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, n-pentyl group, iso-pentyl group, neopentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, and n-docosyl group; and cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclohexyl group. Here, from the viewpoint of the usefulness of the final product, the alkoxymonosilane compound, R 1 ~R 8 and R 11 ~R 16 It is preferable that the group is an alkoxy group. Furthermore, the alkyl group of the alkoxy group is preferably a linear alkyl group or a branched alkyl group. Among these, methyl and ethyl groups are preferred, with methyl groups being more preferred. That is, R 1 ~R 8 and R 11 ~R 16 A methoxy group or an ethoxy group is preferred, with a methoxy group being more preferred.

[0026] Furthermore, the value of n is preferably an integer from 0 to 3, more preferably an integer from 0 to 2, even more preferably 0 or 1, and even more preferably 0, from the viewpoint of ease of production of the alkoxymonosilane compound. Furthermore, the value of m is preferably an integer from 0 to 3, more preferably an integer from 0 to 2, even more preferably 0 or 1, and even more preferably 0, from the viewpoint of ease of production of the alkoxymonosilane compound.

[0027] Furthermore, from the viewpoint of ease of production of the alkoxymonosilane compound, the preferred compound as the polyorganosiloxane compound (A) is the chain-like organopolysiloxane compound (A1) represented by the above general formula (a1). From the same viewpoint, among these, hexamethoxydisiloxane and hexaethoxydisiloxane are preferred, and hexamethoxydisiloxane is more preferred.

[0028] The polyorganosiloxane compound (A) may be used alone or in combination of two or more types. Furthermore, the chain-like organopolysiloxane compound (A1) represented by the general formula (a1) above may be used alone or in combination of two or more types. Furthermore, the cyclic organopolysiloxane compound (A2) represented by the above general formula (a2) may be used alone or in combination of two or more types.

[0029] (Conditions for electrochemical methods) The atmosphere in which the electrochemical method is carried out is not particularly limited; for example, it may be in an air atmosphere or an inert gas atmosphere. Examples of inert gases include noble gases such as helium and argon; and nitrogen gas.

[0030] The temperature (electrolytic cell temperature) when carrying out the electrochemical method is not particularly limited and may be room temperature. Similarly, the pressure (electrolytic cell pressure) when carrying out the electrochemical method is not particularly limited and may be atmospheric pressure. In this embodiment, as described above, an alcohol-derived alkoxide is generated by the electrochemical method and used as a trigger for the reaction, so the reaction proceeds even at room temperature and atmospheric pressure, and an alkoxymonosilane compound is produced. However, when using an alcohol with a large number of carbon atoms, heating may be performed to a temperature higher than the melting point of the alcohol, from the viewpoint of keeping the alcohol in a liquid state.

[0031] When performing the electrochemical method, the amount of electricity is preferably 1.0 F / mol or more, more preferably 1.5 F / mol or more, and even more preferably 2.0 F / mol or more, from the viewpoint of improving the yield of the alkoxymonosilane compound. There is no particular upper limit to the amount of electricity, but from the viewpoint of the effect of improving the yield of the alkoxymonosilane compound in relation to the amount of electricity input, it is usually 6.0 F / mol or less. The amount of electricity refers to the value calculated by the method described in the examples below.

[0032] Furthermore, when performing electrochemical methods, it is preferable to stir the alcohol in the electrolytic cell from the viewpoint of improving the yield of the alkoxymonosilane compound. Any standard stirring method, such as using a magnetic stirrer, can be used as appropriate.

[0033] (Reaction in process (S1)) In step (S1), an alkoxymonosilane compound is produced by the reaction of an alcohol-derived alkoxide, generated by an electrochemical method, with an organopolysiloxane compound (A). An organosylanooxide is also produced along with the alkoxymonosilane compound. In this embodiment, organosiloxide refers to a compound derived from organopolysiloxane compound (A) that has the following structure at its terminus.

[0034] [ka] In the above general formula, R is independently either a hydrocarbon group or an oxygen-containing hydrocarbon group.

[0035] For example, when a chain-like organopolysiloxane compound (A1) represented by the above general formula (a1) is used as a raw material, alcohol R a Reaction with alkoxides derived from OH groups produces organosilanoxide (a1-1) and alkoxymonosilane compounds (a1-2), as shown in reaction formula 1 below. Alternatively, organosilanoxide (a1-3) and alkoxymonosilane compounds (a1-4) are produced, as shown in reaction formula 2 below. Alcohol R a R possessed by OH a Examples of hydrocarbon groups found in alcohols include those mentioned above.

[0036] [ka]

[0037] [ka]

[0038] Furthermore, for example, when a cyclic organopolysiloxane compound (A2) represented by the above general formula (a2) is used as a raw material, alcohol R a Reaction with alkoxides derived from OH groups produces organosilanoxide (a2-1) and alkoxymonosilane compounds (a2-2), as shown in reaction formula 3 below. Alternatively, organosilanoxide (a2-3) and alkoxymonosilane compounds (a2-4) are produced, as shown in reaction formula 4 below.

[0039] [ka]

[0040] [ka]

[0041] Here, the organosyloxide is alkoxideized by reacting with an alcohol. Since the alkoxideized organosyloxide is an organopolysiloxane compound, this organopolysiloxane compound reacts with the alkoxide produced by electrochemical means to further generate an alkoxymonosilane compound.

[0042] For example, using reaction equation 1 with a linear organopolysilane compound (A1) as a starting material, the organosilanoxide (a1-1) reacts with alcohol R a It reacts with OH to undergo alkoxylation, producing the organopolysilane compound (A1') represented by general formula (a1'). Then, the chain-like organopolysilane compound (A1') represented by general formula (a1') is produced by electrochemical methods. a Reaction with alkoxides derived from OH groups produces organosilanoxide (a1'-1) and alkoxymonosilane compounds (a1'-2).

[0043] [ka]

[0044] By repeating the reaction processes described in reaction equations 1 and 1a above, ultimately, as shown in the reaction equation below, the same number of alkoxymonosilane compounds as the silicon elements present in the linear organopolysilane compound (A1) are produced from the linear organopolysilane compound (A1).

[0045] [ka]

[0046] Furthermore, when a cyclic organopolysilane compound (A2) is used as a raw material, the same number of alkoxymonosilane compounds as the silicon elements present in the cyclic organopolysilane compound (A2) are produced, similar to the case with the chain-like organopolysilane compound (A1).

[0047] [ka]

[0048] (Dehydrating agent) In the method for producing the alkoxymonosilane compound of this embodiment, it is preferable to add a dehydrating agent to the alcohol in the electrolytic cell from the viewpoint of promoting the alkoxylation of the organosylanoxide. When organosilanoxides are alkoxylated, water is produced as a byproduct. If water accumulates in the electrolytic cell, the alkoxylation of organosilanoxides is inhibited. Therefore, by adding a dehydrating agent to the alcohol in the electrolytic cell, the alkoxylation of organosilanoxides can be promoted, thereby accelerating the formation of alkoxymonosilane compounds from organopolysilane compounds (A).

[0049] Examples of dehydrating agents include adsorbent solid dehydrating agents such as zeolites and molecular sieves. The amount of dehydrating agent to be added is preferably 10 mg / mL to 4,000 mg / mL, more preferably 100 mg / mL to 2,000 mg / mL, and even more preferably 500 mg / mL to 1,000 mg / mL. [Examples]

[0050] The present invention will be specifically described by the following examples, but the present invention is not limited to the following examples.

[0051] [Examples 1-8 and Comparative Examples 1-5] Alkoxymonosilane compounds were produced from organopolysiloxane compound (A) using the methods described in Examples 1-8 and Comparative Examples 1-5, and the evaluations described later were performed.

[0052] <Raw materials> • Organopolysiloxane compound (A): Hexamethoxydisilane (HMDS) (manufactured by Tokyo Chemical Industry Co., Ltd.) • Alcohol: Methanol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) • Supporting electrolyte 1: Tetrabutylammonium tetrafluoroborate (nBu4NBF4) (manufactured by Tokyo Chemical Industry Co., Ltd.) • Supporting electrolyte 2: Lithium perchlorate (LiClO4) (manufactured by Tokyo Chemical Industry Co., Ltd.) • Supporting electrolyte 3: Tetrabutylammonium perchlorate (nBu4NClO4) (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0053] <Example 1> 5 mL of methanol solution, adjusted to an nBu4NBF4 concentration of 0.1 M, was added to a 10 mL electrolytic cell (IKA, material: glass), along with 0.5 mmol of HMDS. A working electrode (length 52.5 mm, width 8.0 mm, thickness 2.0 mm) and a counter electrode (length 52.5 mm, width 8.0 mm, thickness 2.0 mm) made of graphite were immersed in the methanol solution. The methanol solution was then stirred for 40 minutes at a stirring speed of 500 rpm using a magnetic stirrer while a current of -20 mA was applied to the counter electrode (electrical charge Q: 1.0 F / mol). These operations were carried out inside a glove box under a nitrogen atmosphere. In the examples and comparative examples, the amount of electricity Q (F / mol) was calculated as follows. First, the electric charge Q(C) was calculated using the formula "electric charge Q(C) = current value (A) × time (seconds)". Next, the electric charge Q(C) is given by the Faraday constant (9.65 × 10⁻¹⁰). 4 The number of moles of electrons supplied to the reaction system was calculated by dividing by (C / mol). Then, the value of "(number of moles of electrons supplied to the reaction system) / (number of moles of HMDS used as raw material)" was calculated, and this value was defined as the electric charge Q (F / mol).

[0054] <Example 2> The supporting electrolyte was changed from nBu4NBF4 to LiClO4, and the experiment was conducted under the same conditions as in Example 1 (electrical charge: 1.0 F / mol).

[0055] <Example 3> The supporting electrolyte was changed from nBu4NBF4 to nBu4NClO4, and the experiment was conducted under the same conditions as in Example 1 (electrical charge: 1.0 F / mol).

[0056] <Example 4> In Example 4, the energizing and stirring time was extended to 80 minutes (electrical energy: 2.0 F / mol).

[0057] <Example 5> In Example 3, before starting the energization and stirring, 1,000 mg / mL of molecular sieves 3A (MS3A, manufactured by Nacalai Tesque, model number "04176-55", powder) was added to the methanol solution as a dehydrating agent.

[0058] <Example 6> In Example 5, the energizing and stirring time was extended to 80 minutes (electrical energy: 2.0 F / mol).

[0059] <Example 7> In Example 3, before starting the energization and stirring, molecular sieves 3A (MS3A, Merck, model number "1.05704.0250", beads) were added to the methanol solution at a concentration of 1,000 mg / mL relative to the methanol solution as a dehydrating agent.

[0060] <Example 8> In Example 7, the energizing and stirring time was extended to 80 minutes (electrical energy: 2.0 F / mol).

[0061] <Comparative Example 1> The same experiment as in Example 1 was carried out without applying power (electrical charge: 0.0 F / mol).

[0062] <Comparative Example 2> The same experiment as in Example 2 was carried out without applying any power (electrical charge: 0.0 F / mol).

[0063] <Comparative Example 3> The same experiment as in Example 3 was carried out without applying any power (electrical charge: 0.0 F / mol).

[0064] <Comparative Example 4> The same experiment as in Example 5 was carried out without applying power (electrical charge: 0.0 F / mol).

[0065] <Comparative Example 5> The same experiment as in Example 7 was carried out without applying any power (electrical charge: 0.0 F / mol).

[0066] <Rating> After the experiment was completed, the solution in the electrolytic cell was collected and analyzed by gas chromatography (Shimadzu Corporation, GC-2014ATF / SPL). The yields of hexamethoxydisilane (HMDS) and tetramethoxysilane (TMOS) were determined by an internal standard method using mesitylene as the internal standard. The product (TMOS) was identified using GC-MS (Shimadzu Corporation, GCMS-QP2020). When using MS3A, the solution collected from the electrolytic cell was filtered using filter paper (DISMIC-13HP, pore size: 0.20 μm, manufactured by Advantec Co., Ltd.) and then subjected to gas chromatography. The results are shown in Table 1.

[0067] [Table 1]

[0068] From Table 1, the following can be seen. In Examples 1-8, where electricity was applied, it can be seen that TMOS was successfully generated from HMDS in all cases. Among these, it can be seen that the TMOS yield improved particularly in Examples 5-8, where a dehydrating agent was used. Furthermore, it can be seen that the TMOS yield tends to improve as the amount of electricity applied increases, and this trend is especially pronounced when a dehydrating agent is used. The reason why the total amount of HMDS and TMOS in Examples 1-8 is significantly less than 100% is that TMOS polymers (trimers and tetramers) were detected as by-products other than TMOS. In contrast, in Comparative Examples 1-5, where no power was applied, it can be seen that TMOS was not effectively generated from the HMDS in any of them.

Claims

1. A method for producing an alkoxymonosilane compound, comprising step (S1) of contacting an alcohol containing an alkoxide generated by an electrochemical method with an organopolysiloxane compound (A) in an electrolytic cell containing an alcohol containing a supporting electrolyte.

2. A method for producing an alkoxymonosilane compound according to claim 1, wherein a dehydrating agent is added to the alcohol in the electrolytic cell.

3. The method for producing an alkoxymonosilane compound according to claim 1 or 2, wherein the organopolysiloxane compound (A) is one or more selected from the group consisting of a chain-like organopolysiloxane compound (A1) represented by the following general formula (a1) and a cyclic organopolysiloxane compound (A2) represented by the following general formula (a2). 【Chemistry 1】 [In the general formula (a1) and the general formula (a2), R １ ~R ８ and R １１ ~R １６ Each of these is independently an alkyl group having 1 to 21 carbon atoms or an alkoxy group having 1 to 21 carbon atoms. n is an integer from 0 to 4. m is an integer from 0 to 4.

4. The linear organopolysiloxane compound (A1) and the cyclic organopolysiloxane compound (A2) have R １ ~R ８ and R １１ ~R １６ This is an alkoxy group having 1 to 21 carbon atoms. The R that the chain-like organopolysiloxane compound (A1) has １ ~R ８ is the same alkoxy group, The cyclic organopolysiloxane compound (A2) has R １１ ~R １６ These are the same broker group, Furthermore, the number of carbon atoms in the alcohol is R １ ~R ８ and R １１ ~R １６ A method for producing an alkoxymonosilane compound according to claim 3, wherein the number of carbon atoms is the same as that of the compound.

5. The method for producing an alkoxymonosilane compound according to claim 3 or 4, wherein the alcohol is a monohydric alkyl alcohol having 1 to 21 carbon atoms.

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