Method for producing organosilicon compound

Abstract

To provide a method for producing an organosilicon compound which can produce an organosilicon compound with a reduced amount of lead components as impurities.SOLUTION: A method for producing an organosilicon compound includes: a reaction step of conducting a Grignard reaction of at least one alkoxysilane selected from the group consisting of a dialkoxysilane, a trialkoxysilane, and a tetraalkoxysilane, an organohalogen compound, and magnesium to prepare a reaction solution; and an irradiation step of irradiating the reaction solution with ultraviolet light.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for producing an organosilicon compound.

Background Art

[0002] Organosilicon compounds are used in a wide range of fields and are attracting attention as important compounds in fields such as the field of materials engineering, the optical field, the pharmaceutical field, or the agricultural field. In the production of organosilicon compounds, it is important to control the structure according to the intended use. As one of the methods for obtaining an organosilicon compound having a desired structure, a synthesis method using a Grignard reaction is known. The Grignard reaction is a reaction using a Grignard reagent generated by the reaction of magnesium and an organic halide, and by utilizing this reaction, a desired organic group or the like can be added to the silicon element in the organosilicon compound. For example, Patent Document 1 discloses a method for producing a tertiary alkylsilane by reacting a silane compound with a tertiary alkyl Grignard reagent. Further, Patent Document 2 discloses a method for producing a dialkyldialkoxysilane by reacting dichlorosilane with a Grignard reagent having a specific structure. Further, Patent Document 3 discloses a method for producing an organosilicon compound in which another alkyl group is added to the silicon of an alkylsilane by reacting an alkylsilane with a Grignard reagent.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] As described above, it has been conventionally known to utilize the Grignard reaction to obtain an organosilicon compound having a desired structure. In the course of studying this reaction, the present inventors observed that a component containing lead, which is a heavy metal, as a by-product (lead component) can be generated during the reaction. Although it is preferable that the amount of the lead component in the finally obtained product is small, no studies have been conducted to efficiently reduce the amount of the lead component, particularly from the viewpoint of the type of organosilicon compound used in the Grignard reaction, and there has been room for improvement. Therefore, an object of the present invention is to provide a method for producing an organosilicon compound capable of obtaining an organosilicon compound with a small amount of lead component as an impurity.

Means for Solving the Problems

[0005] As a result of intensive studies, the present inventors have found that the above problems can be solved by using a specific type of organosilicon compound as the organosilicon compound used in the Grignard reaction and further utilizing a treatment of irradiating with ultraviolet rays, and have completed the present invention.

[0006] That is, the gist of the present invention is as follows. Item 1 A reaction step of performing a Grignard reaction using at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane, an organic halide, and magnesium to obtain a reaction solution, and An irradiation step of irradiating the reaction solution with ultraviolet rays, A method for producing an organosilicon compound, comprising: Item 2 The method for producing an organosilicon compound according to Item 1, wherein the ratio of the total amount (mol) of halogen groups (X) contained in the entire organic halide used to the total amount (mol) of alkoxy groups contained in the entire alkoxysilane used is 0.50 mol / mol or more and 8.0 mol / mol or less. Item 3. The method for producing an organosilicon compound according to Item 1 or 2, wherein in the reaction step, an organic solvent is further used. Item 4. The method for producing an organosilicon compound according to Item 3, wherein the ratio of the total amount used (mol) of the alkoxysilane to the total amount used (L) of the organic solvent is 0.10 mol / L or more and 6.0 mol / L or less. Item 5. The method for producing an organosilicon compound according to any one of Items 1 to 4, including a purification treatment for purifying the reaction solution after the irradiation step. Item 6. The method for producing an organosilicon compound according to any one of Items 1 to 5, including a liquid separation treatment for separating the reaction solution into an organic phase and an aqueous phase by mixing an aqueous solution containing an acid and the reaction solution after the reaction step and before the irradiation step. Item 7. The method for producing an organosilicon compound according to Claim 6, wherein the acid is an acid capable of forming a salt with magnesium and the salt is a salt insoluble in water. Item 8. The method for producing an organosilicon compound according to Claim 7, wherein the acid is at least one acid selected from the group consisting of oxalic acid, carbonic acid, and tartaric acid.

Advantages of the Invention

[0007] According to the present invention, it is possible to provide a method for producing an organosilicon compound capable of obtaining an organosilicon compound with a small amount of lead component as an impurity.

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to these contents unless it exceeds the gist. Further, the present invention can be arbitrarily modified and implemented within the scope not departing from the gist. In this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as a lower limit value and an upper limit value, and "A~B" means A or more and B or less. Further, when the numerical range is described stepwise, the upper limit and the lower limit of each numerical range can be arbitrarily combined. In addition, the expression "A or B" in this specification may be construed as "at least one selected from the group consisting of A and B". In addition, the expression "the amount of B relative to the amount of A" in this specification represents "the amount of B / the amount of A". In addition, although multiple embodiments are described in this specification, various conditions in each embodiment can be applied to each other within the applicable range.

[0009] <Method for Producing Organosilicon Compound> A method for producing an organosilicon compound according to an embodiment of the present invention (hereinafter, also simply referred to as "method for producing an organosilicon compound") is a reaction step of performing a Grignard reaction using at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane, an organic halide, and magnesium to obtain a reaction solution, and an irradiation step of irradiating the reaction solution with ultraviolet light. It is a method for producing an organosilicon compound including The above production method may include steps other than the above reaction step and irradiation step.

[0010] Heavy metals affect the human body and cause health hazards when excessively taken into the body. It is known that, in particular, lead, which is a kind of heavy metal, is likely to accumulate in the body and difficult to excrete, so it is likely to cause poisoning symptoms. Therefore, it is preferable that the amount of lead and / or a compound containing lead (hereinafter, collectively referred to as "lead component" for "lead and / or a component containing lead") in the product is small. Here, when a lead component is contained in the materials used for organic synthesis, the lead component reacts with the organic compound during the process of organic synthesis, and an organolead compound is generated. Since organolead compounds are easily soluble in organic solvents and hardly soluble in aqueous solvents, it is difficult to remove them by processes such as liquid separation in the synthesis of organic compounds, etc. Also, since the molecular size tends to be larger compared to lead itself (including lead ions) and inorganic lead compounds, there has been a problem that it is difficult to remove them by processes such as filtration and adsorption. Lead components may be included in various products and may also be included in materials used for the synthesis of organosilicon compounds. In particular, magnesium is used in the Grignard reaction, and commercially available magnesium (commercial products) usually contains lead components such as lead(II) chloride or lead(IV) chloride as impurities.

[0011] As a result of intensive studies, the inventors have found that the bond between the lead atom and the carbon atom in the organolead compound can be cleaved by irradiation with ultraviolet light, and further that the lead component with a reduced molecular size by ultraviolet irradiation can be easily removed by purification treatment or the like. As a result of further studies, the inventors have found that the efficiency of removing the lead component varies depending on the type of silane compound used as a raw material for the synthesis of the organosilicon compound. Specifically, when synthesizing an organosilicon compound using the Grignard reaction, when at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane (hereinafter also referred to as "specific alkoxysilane") is used as a raw material, it has been found that the cleavage of the bond between the lead atom and the carbon atom in the organolead compound by ultraviolet irradiation is carried out more efficiently compared to the case where halosilane is used as a raw material. As a result of the studies by the inventors, halosilane has a high reactivity with magnesium, and a substance that absorbs ultraviolet light (a substance containing at least a silicon atom and a carbon atom according to the analysis of the inventors) is likely to be generated by the side reaction between halosilane and magnesium, while specific alkoxysilane has a lower reactivity with magnesium compared to halosilane, so it has been found that a substance that absorbs ultraviolet light is less likely to be generated. From the above, in the production method according to this embodiment, since the hardly removable organolead compound can be easily removed during the production process, an organosilicon compound with a small amount of lead component as an impurity can be obtained.

[0012] [Reaction step] The method for producing an organosilicon compound includes a reaction step of performing a Grignard reaction using at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane, an organic halide, and magnesium to obtain a reaction solution. The mode of using each component to be subjected to the reaction is not particularly limited. For example, a mode in which a solution in which an alkoxysilane and an organic halide are dissolved in a solvent is dropped into a solvent in which magnesium is dispersed can be mentioned.

[0013] (Specific alkoxysilane) The specific alkoxysilane is not particularly limited as long as it is at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane. However, from the viewpoint of reaction activity, trialkoxysilane is preferable. The specific alkoxysilane may be used alone or in combination of two or more.

[0014] The specific alkoxysilane can be represented by the following formula (1). Si(R 2 ) b (OR 3 ) 4-b (1) In the above formula (1), R 2 each independently represents a hydrogen atom or a monovalent organic group; R 3 each independently represents an alkyl group; and b represents an integer of 0 to 2.

[0015] R 2 is not particularly limited as long as each independently represents a hydrogen atom or a monovalent organic group, and may be a hydrogen atom or a monovalent hydrocarbon group. However, from the viewpoint of reactivity, it is preferably a hydrogen atom. The monovalent organic group may have a linear structure, a branched structure, a ring structure (alicyclic structure and / or aromatic ring structure), or an unsaturated bond. R 2The monovalent hydrocarbon group according to [ID] is not particularly limited, but from the viewpoint of reactivity, the number of carbon atoms in the hydrocarbon group is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 2.

[0016] R 3 is not particularly limited as long as it is an alkyl group independently, and the alkyl group may have a straight-chain structure or a branched-chain structure. A plurality of R 3 are preferably all the same. R 3 The alkyl group according to [ID] is not particularly limited, but from the viewpoint of reactivity, the number of carbon atoms in the alkyl group is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 2.

[0017] b is not particularly limited as long as it is an integer of 0 to 2, but from the viewpoint of reactivity, 1 (that is, trialkoxysilane) is preferable.

[0018] Specific examples of the dialkoxysilane include dimethoxysilane, methyldimethoxysilane, ethyldimethoxysilane, propyldimethoxysilane, butyldimethoxysilane, vinyldimethoxysilane, phenyldimethoxysilane, dimethyldimethoxysilane, methylethyldimethoxysilane, or diethyldimethoxysilane and other dimethoxy-based silanes; diethoxysilane, methyldiethoxysilane, ethyldiethoxysilane, propyldiethoxysilane, butyldiethoxysilane, vinyldiethoxysilane, phenyldiethoxysilane, dimethyldiethoxysilane, methylethyldiethoxysilane, or diethyldiethoxysilane and other diethoxy-based silanes; or dipropoxysilane, methyldipropoxysilane, ethyldipropoxysilane, propyldipropoxysilane, butyldipropoxysilane, vinyldipropoxysilane, phenyldipropoxysilane, dimethyldipropoxysilane, methylethyldipropoxysilane, or diethyldipropoxysilane and other dipropoxy-based silanes and the like. Examples of the trial alkoxysilane include, specifically, trimethoxysilane-based silanes such as trimethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, vinyltrimethoxysilane, or phenyltrimethoxysilane; triethoxysilane-based silanes such as triethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, or phenyltriethoxysilane; and tripropoxysilane-based silanes such as tripropoxysilane, methyltripropoxysilane, ethyltripropoxysilane, vinyltripropoxysilane, or phenyltripropoxysilane. Examples of the tetraalkoxysilane include, specifically, tetramethoxysilane, tetraethoxysilane, or tetrapropoxysilane.

[0019] Since it is possible to obtain an organosilicon compound by using an alkoxysilane, an organic halide, and magnesium, the amount of the alkoxysilane used is not particularly limited. For example, when a solvent described later (preferably an organic solvent) is used in the reaction step, the ratio of the total amount of the alkoxysilane used (mol) to the total amount of the solvent used (L) is preferably 0.10 mol / L or more, more preferably 0.30 mol / L or more from the viewpoint of reactivity, still more preferably 0.50 mol / L or more, particularly preferably 0.70 mol / L or more. Also, from the viewpoint of the solubility of the reaction product, it is preferably 6.0 mol / L or less, more preferably 4.0 mol / L or less, still more preferably 3.0 mol / L or less, and particularly preferably 2.0 mol / L or less. In the description of the reaction step, the "total amount used" means the total amount of the substance used throughout the reaction. For example, when a solution in which an alkoxysilane and an organic halide are dissolved in a solvent is dropped into a solvent in which magnesium is dispersed to carry out the reaction, the total amount of the solvent used is the sum of the amount of the solvent in the solvent in which magnesium is dispersed and the amount of the solvent in the solution in which the alkoxysilane and the organic halide are dissolved.

[0020] (Organic halide) The organic halide is not particularly limited as long as it is an organic group having a halogen atom. The organic halide may be used alone or in combination of two or more.

[0021] The organic halide can be represented by the following formula (2). R 1 X a (2) In the above formula (2), R 1 represents an a-valent organic group; X each independently represents a halogen atom; a represents an integer of 1 or more. The valence of this organic group is determined by the number of X atoms to which it is bonded. For example, if the number of X atoms is 1, it is monovalent; if the number of X atoms is 2, it is divalent; if the number of X atoms is 3, it is trivalent. Also, these hydrocarbons may have substituents within the range where the effects of the present invention can be obtained.

[0022] R 1 is not particularly limited as long as it is an a-valent organic group, and may be, for example, an a-valent hydrocarbon group, which may have a linear structure, a branched structure, a ring structure (alicyclic structure and / or aromatic ring structure), or an unsaturated bond. R 1 The hydrocarbon group related to R is not particularly limited, but from the viewpoint of reactivity, the number of carbon atoms of the hydrocarbon group is preferably 1 to 12, more preferably 1 to 10, and even more preferably 1 to 6.

[0023] X is not particularly limited as long as each independently represents a halogen atom, and may be any of a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. From the viewpoint of reactivity, a chlorine atom or a bromine atom is preferred, and a bromine atom is more preferred.

[0024] a is not particularly limited as long as it is an integer of 1 or more, but from the viewpoint of reactivity, it is preferably 1 to 4, and more preferably 1 to 2.

[0025] Examples of the organic halide include, specifically, alkyl halides such as chloromethane, chloroethane, chloropropane, 2-chloropropane, 1-chloro-2-methylpropane, 2-chloro-2-methylpropane, 2-bromo-2-methylpropane, chlorobutane, bromobutane, chloropentane, chlorocyclopentane, chlorohexane, bromomethane, bromoethane, bromopropane, 2-bromopropane, 1-bromo-2-methylpropane, bromopentane, bromocyclopentane, bromohexane, iodomethane, iodoethane, iodopropane, 2-iodopropane, 1-iodo-2-methylpropane, iodopentane, iodocyclopentane, or iodohexane; alkenyl halides such as vinyl chloride, allyl chloride, 2-methylallyl chloride, vinyl bromide, allyl bromide, 2-methylallyl bromide; aryl halides such as chlorobenzene, α-chlorotoluene, bromobenzene, α-bromotoluene, iodobenzene, or α-iodotoluene; alkylenedihalides such as 1,3-dichloropropane, 1,4-dichlorobutane, 1,5-dichloropentane, 1,3-dibromopropane, 1,4-dibromobutane, 1,5-dibromopentane, 1,3-diiodopropane, 1,4-diiodobutane, or 1,5-diiodopentane; or arylenedihalides such as o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, o-dibromobenzene, m-dibromobenzene, p-dibromobenzene, o-diiodobenzene, m-diiodobenzene, or p-diiodobenzene; and the like.

[0026] Since it is possible to obtain an organosilicon compound by using an alkoxysilane, an organic halide, and magnesium, the amount of the organic halide used is not particularly limited, but the appropriate usage ratio varies depending on the target reaction product. For example, when reacting all alkoxy groups, the alkoxy groups (OR 3) The ratio of the total amount (mol) of halogen groups (X) contained in the entire organic halide used to the total amount (mol) of is preferably 0.10 mol / mol or more, more preferably 0.20 mol / mol or more, still more preferably 0.40 mol / mol or more, and particularly preferably 0.50 mol / mol or more from the viewpoint of reactivity. Also, from the viewpoints of the concentration of the reaction solution and the cost of the raw material usage amount, it is preferably 20 mol / mol or less, more preferably 12 mol / mol or less, still more preferably 10 mol / mol or less, and particularly preferably 8.0 mol / mol or less. For example, when X mol of dialkoxysilane is used as the alkoxysilane and Y mol of alkyl monohalide is used as the organic halide, the above ratio is represented by Y / 2X mol / mol.

[0027] (Magnesium) The form of magnesium is not particularly limited and can be used in known manners. In this specification, "magnesium" means magnesium atoms unless otherwise specified, and magnesium atoms can exist, for example, in the form of metallic magnesium or magnesium salts. However, since the Grignard reaction is carried out using metallic magnesium, the magnesium used in the reaction contains at least metallic magnesium.

[0028] Since it is possible to obtain an organosilicon compound by using an alkoxysilane, an organic halide, and magnesium, the amount of metallic magnesium used is not particularly limited. For example, from the viewpoint of reaction efficiency, the ratio of the total amount (mol) of metallic magnesium used to the total amount (mol) of halogen groups (X) contained in the entire organic halide used is preferably 0.20 mol / mol or more, more preferably 0.40 mol / mol or more, still more preferably 0.50 mol / mol or more, and particularly preferably 0.90 mol / mol or more. Also, from the viewpoint of the post-treatment of the unreacted metallic magnesium remaining after the completion of the reaction, it is preferably 50 mol / mol or less, more preferably 25 mol / mol or less, still more preferably 10 mol / mol or less, and particularly preferably 7.0 mol / mol or less.

[0029] (Other components) In the reaction step, components other than the above specific alkoxysilane, organic halide, and magnesium (other components) may be used as long as the effects of the present invention are not impaired. For example, a solvent or an additive can be used.

[0030] In the reaction step, a solvent can be further used. The solvent is not particularly limited as long as it can dissolve the above components and any components that can be added. However, an organic solvent such as a hydrocarbon-based solvent or an ether-based solvent is preferred, and an ether-based solvent is more preferred. Examples of the ether-based solvent include diethyl ether, diisopropyl ether, dibutyl ether, tert-butyl methyl ether, 1,2-dimethoxyethane, tetrahydro furan, 2-methyltetrahydrofuran, or 1,4-dioxane. Among these, tetrahydrofuran is preferred from the viewpoints of reaction control and ease of industrial availability. The solvent may be used alone or in combination of two or more.

[0031] The amount of the solvent used is not particularly limited, but for example, it is preferably used so as to satisfy the ratio of the total amount (mol) of the alkoxysilane to the total amount (L) of the solvent described in the above item of the specific alkoxysilane.

[0032] In the reaction step, an additive can be further used. Examples of the additive include components added for the purpose of promoting the Grignard reaction, and the component is not particularly limited as long as it can be dissolved in the above solvent, and typical examples include iodine.

[0033] As described above, the reaction solution obtained by the reaction usually contains an organolead compound. The content of the organolead compound in the reaction solution is not particularly limited, and may be, for example, 1 ppb to 1000 ppm in terms of mass, 10 ppb to 100 ppm, or 10 ppb to 1 ppm.

[0034] The method for analyzing the types and contents of the components contained in a liquid such as a reaction solution is not particularly limited, and it can be analyzed by a known method.

[0035] (Grignard reaction) In the Grignard reaction described in this specification, an organohalide (R 1 X a ; R 1 is an organic group, X is independently a halogen atom, and a is an integer of 1 or more) reacts with magnesium (Mg) to generate a Grignard reagent (for example, when a = 1, R 1 MgX), and then the Grignard reagent reacts with a specific alkoxysilane (Si(R 2 ) b (OR 3 ) 4-b ; R 2 is independently an organic group, and R 3 is independently an organic group, and b is an integer of 0 to 2 or more), and at least a part of (OR 3 ) of the alkoxysilane is substituted with R 1 to generate an organosilicon compound. The reaction process only needs to include at least the treatment of the Grignard reaction, and may also include other treatments.

[0036] The method for carrying out the Grignard reaction is not particularly limited and can be carried out by a known method. The reaction temperature for carrying out the Grignard reaction is not particularly limited, but from the viewpoint of promoting the reaction, it is preferably 0 °C or higher, more preferably 10 °C or higher, still more preferably 20 °C or higher, particularly preferably 30 °C or higher. Also, from the viewpoint of the stability of the Grignard reagent, which is the first stage of the reaction, it is preferably 100 °C or lower, more preferably 80 °C or lower, still more preferably 60 °C or lower. Also, the reaction time for carrying out the Grignard reaction is not particularly limited, but from the viewpoint of the heat removal efficiency of the Grignard reaction with a large heat generation amount, it is preferably 0.1 hour or longer, more preferably 0.5 hour or longer, still more preferably 1 hour or longer. Also, from the viewpoint of the synthesis efficiency, it is preferably 24 hours or shorter, more preferably 12 hours or shorter, still more preferably 8 hours or shorter, particularly preferably 6 hours or shorter. Also, the atmosphere for carrying out the Grignard reaction is not particularly limited and can be carried out in the air, but it is preferably carried out in an inert gas such as nitrogen gas or argon gas.

[0037] Taking an example of the Grignard reaction, when an organic halide (R 1 X2), a specific alkoxysilane (Si(R 2 )(OR 3 )3), and magnesium (Mg) are used, first, a Grignard reagent (R 1 (X)MgX) is generated by the reaction of the organic halide and magnesium (Mg), and then the Grignard reagent reacts with the specific alkoxysilane, and at least a part of (OR 3 ) of the alkoxysilane is substituted with R 1 , and an organosilicon compound having the structure represented by the following formula (3) (hereinafter, also referred to as compound (3)) is generated. ​ Furthermore, by reacting compound (3) with magnesium (Mg), a Grignard reagent (XMgR 1 Si(R 2 )(OR 3 )2) is generated. Subsequently, the reaction between the Grignard reagent and an alkoxysilane or between the Grignard reagent and compound (3) is repeated multiple times to generate an organosilicon compound having the structure represented by the following formula (4) (hereinafter also referred to as compound (4)). In formula (4), n represents the number of repetitions and is an integer of 2 or more.

[0038]

Chemical formula

[0039]

Chemical formula

[0040] The specific alkoxysilane used in the above reaction has relatively low reactivity, and since it is difficult to generate a substance that absorbs ultraviolet light due to side reactions between the silane halide and magnesium, the bond between the lead atom and the carbon atom in the organolead compound can be efficiently cleaved by the step of irradiating ultraviolet light described later. Therefore, the lead component can be easily removed from the reaction solution, and thus the lead component in the organosilicon compound produced by the method according to this embodiment can be reduced.

[0041] a in formula (3) is not particularly limited and can be appropriately designed according to the use of the obtained organosilicon compound. From the perspective of the weight-average molecular weight, the molecular weight of the organosilicon compound may be, for example, 200 or more, 300 or more, 400 or more, and may also be 1000 or less, 800 or less, 600 or less. This weight-average molecular weight can be measured by gel permeation chromatography (hereinafter abbreviated as GPC) or the like.

[0042] The measurement of the weight-average molecular weight using GPC can be carried out, for example, using an apparatus such as a high-speed GPC apparatus HLC8220GPC or HLC8420GPC (both manufactured by Tosoh Corporation). Further, tetrahydrofuran (without stabilizer, for GPC) can be used as the eluent, and the detailed analysis conditions can be the conditions shown in Table 1 below. In this case, the weight-average molecular weight can be evaluated as a value converted based on the calibration curves prepared using standard polystyrene and p-t-butoxystyrene.

[0043]

Table 1

[0044] As the standard polystyrene used for preparing the calibration curve, for example, the standard polystyrene shown in Table 2 below (all manufactured by Tosoh Corporation) can be used.

[0045]

Table 2

[0046] In the examples described later, a high-speed GPC apparatus HLC8220GPC (manufactured by Tosoh Corporation) was used as the GPC apparatus, the one shown in Table 2 above was used as the standard polystyrene, and the weight-average molecular weight of the obtained organosilicon compound was measured according to the above method including the conditions in Table 1 above.

[0047] On the other hand, the above compound (4) can also be produced by the following method. As the silane compound, instead of a specific alkoxysilane, a halogenated organosilicon compound Si(R 2 )Y3; Y is a halogen atom) is used. When using the silane compound, an organic halide (R 1 X2), and magnesium (Mg), first, a Grignard reagent (R 1(X)MgX) is generated, and then the Grignard reagent reacts with an organosilicon halide compound, and at least a part of Y of the organosilicon halide compound is replaced by R 1 to produce an organosilicon compound having a structure represented by the following formula (5) (hereinafter, also referred to as compound (5)). Furthermore, by reacting compound (5) with magnesium (Mg), a Grignard reagent (XMgR 1 Si(R 2 )(Y)2) is generated, and then the reaction of the Grignard reagent with an organosilicon halide compound or compound (5) is repeated a plurality of times to produce an organosilicon compound having a structure represented by the following formula (6) (hereinafter, also referred to as compound (6)). Then, when the compound (6) is reacted with an alcohol (R 3 OH), the above compound (4) is generated.

[0048]

Chemical formula

[0049]

Chemical formula

[0050] The organosilicon halide compound used in the above reaction has relatively high reactivity, and a substance that absorbs ultraviolet rays is likely to be generated by a side reaction between the organosilicon halide compound and magnesium. Therefore, it is difficult for the bond between the lead atom and the carbon atom in the organolead compound to be sufficiently cleaved by the step of irradiating ultraviolet rays described later.

[0051] In addition, when attempting to produce an alkoxysilane such as the above-mentioned compound (4), the method according to this embodiment can obtain the target product through a one-step reaction (only the Grignard reaction), while the method using the above-mentioned organosilicon halide compound requires two-step reactions, namely the Grignard reaction and the reaction related to alkoxylation. Therefore, from these comparisons, the method according to this embodiment can reduce the production cost, and ultimately can reduce the product price of the product manufactured using this method.

[0052] As a by-product of the Grignard reaction, magnesium alkoxide halide (MgX(OR 2 )) is produced. This magnesium salt is easily soluble in tetrahydrofuran. As a method for separating it from the target organosilicon compound, precipitation of the salt by substitution with a poor solvent and its filtration or liquid separation can be carried out.

[0053] As described above, in the method according to this embodiment, substances that absorb ultraviolet light, which may be generated by side reactions between the organosilicon halide compound and magnesium, are less likely to be generated.

[0054] [Polycondensation step] The method for producing an organosilicon compound may include a polycondensation step of polycondensing the organosilicon compound obtained in the above reaction step. The polycondensation step can be carried out at any time as long as it is carried out after the above reaction step. Specifically, polycondensation is a series of reaction steps including the hydrolysis reaction of the alkoxy group possessed by the organosilicon compound and the dehydration condensation reaction between the generated silanol groups. The method for carrying out this polycondensation is not particularly limited. For example, a polycondensation reaction can also be carried out in the presence of the organosilicon compound, water, and an acid catalyst. The acid catalyst is not particularly limited, and examples include oxalic acid, hydrochloric acid, nitric acid, acetic acid, or sulfuric acid, etc.

[0055] The method for performing the polycondensation reaction is not particularly limited and can be carried out by known methods. The conditions of the reaction are not particularly limited. The reaction temperature may be, for example, 10 to 80 °C, or 20 to 50 °C, etc., the reaction time may be, for example, 1 to 24 hours, or 1 to 4 hours, etc., and the reaction atmosphere may be, for example, air or an inert gas, etc.

[0056] In the polycondensation step, at the stage where any degree of polymerization is reached, the reaction can be stopped and the reactants can be purified by a liquid separation operation. Further, since the reaction may proceed further due to the residual moisture in the solution, as a known method for removing moisture in the organic solution, an inorganic or organic dehydrating agent can be added. Examples of the dehydrating agent include sodium sulfate anhydrous, magnesium sulfate, calcium chloride, or trimethyl orthoformate, etc.

[0057] [Irradiation step] The method for producing an organosilicon compound includes an irradiation step of irradiating the above reaction solution with ultraviolet light. By irradiating with the ultraviolet light, the bond between the lead atom and the carbon atom in the organolead compound can be cleaved, so that the amount of the organolead compound in the reaction solution can be reduced. The irradiation step may be after the above treatment step, may be before the purification step described later, or may be after the purification step. The method for irradiating ultraviolet light is not particularly limited and can be carried out by known methods.

[0058] The wavelength of the ultraviolet light is not particularly limited, but from the viewpoint of efficiently removing the organolead compound, 210 to 350 nm is preferable, 220 to 320 nm is more preferable, and 240 to 300 nm is even more preferable. At wavelengths exceeding 350 nm, since there is no absorption derived from the organolead compound, the reaction hardly occurs and the removal effect of the organolead compound tends to decrease. At short wavelengths less than 210 nm, side reactions due to the absorption of the organosilicon compound tend to occur easily.

[0059] The ultraviolet irradiation amount is defined by the integrated light amount, and the integrated light amount is not particularly limited, but it may be appropriately adjusted according to the content of the organolead compound in the reaction solution, and is 0.1 to 100 J / cm2 is preferably, 1 to 80 J / cm 2 more preferably, 10 to 60 J / cm 2 even more preferably.

[0060] The integrated light quantity can be obtained by the product of the intensity of ultraviolet rays and the irradiation time. Therefore, it is preferable to appropriately set the intensity of the irradiated ultraviolet rays and the irradiation time so that the integrated light quantity falls within the above range.

[0061] The device for irradiating ultraviolet rays is not particularly limited as long as it uses a light source that emits ultraviolet rays, and an ultraviolet fluorescent lamp, a mercury lamp, a deuterium lamp, an ultraviolet LED, or an ultraviolet laser - etc. can be used.

[0062] The method of irradiating ultraviolet rays is not particularly limited, and it is sufficient to irradiate the reaction solution with ultraviolet rays. However, from the viewpoint of efficiency, as a container for containing the liquid, a quartz container or the like with high ultraviolet permeability is used, and a method of irradiating ultraviolet rays to the container is preferable.

[0063] When the irradiation step is adopted, the reaction solution may contain the following components in terms of enhancing the effect of ultraviolet irradiation. Examples of the components that can enhance the effect of ultraviolet irradiation include photosensitizers such as benzophenone, anthracene, or camphorquinone. Also, when an organolead compound has a polymerizable group such as a (meth)acrylic group, a vinyl group, or an epoxy group, a polymerization inhibitor such as dibutylhydroxytoluene or benzoquinone may be added. The content of these components in the reaction solution is not particularly limited and may be appropriately determined in consideration of the desired effect. For example, if it is a photosensitizer, it may be 1 to 50% by mass, and if it is a polymerization inhibitor, it may be 1 to 50% by mass, for example.

[0064] [Purification step] The method for producing an organosilicon compound may include a purification step (which may also be referred to as "purification treatment") of removing the components to be removed from the above reaction solution, that is, purifying the reaction solution. The components to be removed include the above lead component. The form of the lead component is not particularly limited, but it usually exists as a salt formed by lead ions and anions contained in the liquid. The purification step can be carried out at any time, and may be carried out after the above reaction step to remove impurities in the liquid such as the reaction solution, or may be carried out after the above irradiation step to remove the lead component decomposed by ultraviolet irradiation, or may be carried out in parallel with any step such as the reaction step. However, from the perspective of removing the lead component, it is preferably carried out at least once after the irradiation step. In the description of this section, the object to be purified is referred to as "liquid", and the liquid is a reaction solution obtained by the reaction or the like.

[0065] The method for purification is not particularly limited, and known methods can be used. Specifically, methods using liquid separation treatment, filtration treatment, adsorption treatment, etc. described below can be mentioned. From the perspective of reducing costs because the treatment can be carried out in a batch system, it is preferable to adopt liquid separation treatment. Examples of treatments other than liquid separation treatment that can be carried out in a batch system include concentration treatment and solvent replacement treatment, etc., and known techniques can be applied to these treatments. When purification is carried out by filtration or activated carbon treatment, it is necessary to transfer the liquid in a predetermined container to another container such as a container having a filtration membrane or a container containing activated carbon, and it is difficult to carry out the treatment in a batch system. On the other hand, when liquid separation treatment is adopted, the liquid can be purified in a predetermined container without moving the liquid between containers, so the treatment in a batch system is easy, the manufacturing cost can be reduced, and ultimately the product price of the product manufactured through this treatment can be reduced. It should be noted that the treatments other than liquid separation treatment are not restricted, and treatments other than liquid separation treatment may be appropriately used. For example, each treatment such as liquid separation treatment, concentration treatment, or solvent replacement treatment can be carried out in a batch system, and after passing through the above irradiation step, adsorption treatment or the like can be finally carried out.

[0066] The purification process may utilize one type of treatment or a combination of multiple types of treatments. Also, the number of times of the purification process is not particularly limited and may be once or multiple times. Further, the treatments for purification as described in this section can be used not only for removing lead components but also for removing other components.

[0067] (Liquid separation treatment) By performing liquid separation, impurities in the liquid can be removed. The method of liquid separation is not particularly limited. For example, by bringing the liquid into contact with water or an acid and then removing the aqueous layer, it is possible to remove impurities. When using water, a dilute acid such as nitric acid or hydrochloric acid may be further used to increase the solubility of lead components and the like in water. When using a dilute acid, the concentration of the acid may be, for example, 0.001 - 1.0 mol / L or the like. In the case where liquid separation treatment is performed, the organic phase containing the organosilicon compound is treated as the above reaction solution.

[0068] The temperature when bringing the liquid into contact with water is not particularly limited and may be appropriately set at a temperature at which the organosilicon compound and the organic solvent are stable, and may be 0 - 30°C or the like.

[0069] When liquid separation treatment is employed after the irradiation step, it is possible to significantly reduce the lead content in the liquid containing the lead component decomposed by ultraviolet irradiation, and it is also possible to reduce it to the sub-ppb level on a mass basis. Therefore, by using this removal method, the purity of the component targeted for extraction can be improved and it can be suitably used in applications such as electronic materials and pharmaceutical raw materials. Also, depending on the type of the component targeted for extraction, it is possible to perform known purification operations such as recrystallization or column chromatography to improve the purity.

[0070] Further, after the reaction step and before the irradiation step, a liquid separation treatment may be included in which an aqueous solution containing an acid and the reaction solution are mixed to separate the reaction solution into an organic phase and an aqueous phase. The acid is preferably an acid capable of forming a salt with magnesium, and the salt is preferably a salt insoluble in water. Specifically, the acid is more preferably at least one selected from the group consisting of, for example, oxalic acid, carbonic acid, and tartaric acid. By the above treatment, not only can impurities in the liquid be removed, but also, as will be described below, it is possible to suppress the liquid from becoming a highly viscous single-phase gel-like liquid. The inventors of the present invention have found that when the organosilicon compound contained in the liquid is an organosilicon compound having a coordinating functional group such as an alkoxy group, and further when the liquid contains magnesium, the coordinating functional group coordinates to magnesium and / or a magnesium salt, and the liquid becomes a highly viscous single-phase gel-like liquid. Therefore, as a result of intensive studies by the inventors of the present invention, it has been found that by mixing a liquid containing an organosilicon compound or the like with an aqueous solution containing an acid, it is possible to separate the liquid into an organic phase and an aqueous phase.

[0071] (Filtration treatment) When impurities precipitate in the liquid, the impurities can be removed from the system by a filtration operation. By performing a filtration operation using a filter or filter paper and recovering the filtrate, a liquid with reduced impurities can be obtained.

[0072] (Adsorbent treatment) It is also possible to remove impurities in the liquid by adsorbing them onto an adsorbent by bringing the liquid into contact with the adsorbent. For example, as an adsorbent for removing lead components, an ion exchange resin, chelate resin, activated carbon, or synthetic adsorbent used in known metal treatments can be used.

[0073] Activated carbon can be in any form, such as granular, powdered, or fibrous. The raw material can be derived from natural products such as coconut shells or synthetic resins, and it is preferable to perform heat vacuum drying at 150 - 250 °C as a pretreatment. In the treatment using activated carbon, both batch treatment and column treatment can be applied. In batch treatment, specifically, 1 - 15% by mass of activated carbon is added to the liquid, and after stirring and shaking at a liquid temperature of 0 - 30 °C for 0.5 - 48 hours, the activated carbon is removed by filtration to obtain a liquid with reduced impurities (especially lead components). In column treatment, specifically, after filling activated carbon with an organic solvent in which an organic compound is dissolved in a cylindrical container such as PTFE, PFA, or glass, the liquid is passed through at a liquid temperature of 0 - 30 °C to obtain a liquid with reduced impurities (especially lead components).

[0074] As the ion exchange resin, a cation exchange resin can be used, and any cation exchange resin such as strongly acidic, weakly acidic, gel type, or porous type can be used. Chelating resins can be those known to be used in metal treatment, and specific examples include iminodiacetic acid type, nitrilotriacetic acid type, ethylenediaminetetraacetic acid type, diethylenetriaminepentaacetic acid type, or triethylenetetraminehexaacetic acid type. Synthetic adsorbents can be of polystyrene type or polymethacrylic acid type, and specific examples include styrene - divinylbenzene copolymer, ethylstyrene - divinylbenzene copolymer, or methyl methacrylate - ethylene glycol dimethacrylate copolymer, and those in which the benzene ring of styrene is substituted with a halogen such as bromine can also be used. As a pretreatment for ion exchange resins, chelating resins, or synthetic adsorbents, it is preferable to replace the solvent in the resin with a solvent that may be contained in the liquid after treatment by a known method. In the treatment of liquids containing impurities (especially lead components) with ion exchange resins, chelating resins, or synthetic adsorbents, both batch treatment and column treatment can be applied, and specifically, a liquid with reduced impurities (especially lead components) can be obtained by the same operations as the above - mentioned activated carbon treatment.

[0075] The concentration of lead atoms in the reaction solution after the purification process is not particularly limited, and the lower the concentration, the more preferable it is. It is preferably 500 mass ppb or less, more preferably 100 mass ppb or less, even more preferably 50 mass ppb or less, particularly preferably 10 mass ppb or less, and extremely particularly preferably 3 mass ppb or less. The lower limit of the concentration does not require a specific setting, and it may be 0 mass ppb (below the detection limit), may be 0 mass ppb or more, or may be more than 0 mass ppb. The method for evaluating the concentration of the above-mentioned lead atoms is not particularly limited, but it can be carried out using ICP-MS (for example, ICP-MS7900 manufactured by Agilent Technologies).

[0076] <Use of the organosilicon compound> The organosilicon compound produced by the above-mentioned method for producing an organosilicon compound is not limited in its use, but can be used in fields such as the field of materials engineering, the field of electronic materials, the field of pharmaceuticals, or the field of agriculture. Specifically, an alkoxysilane compound, which is a kind of organosilicon compound, can not only be used as a material such as a surface modifier, an adhesion promoter, or a crosslinking agent by itself, but can also be used as a raw material for synthesizing a compound having a siloxane bond. In the above-mentioned method for producing an organosilicon compound, the lead component can be reduced to the sub-ppb level on a mass basis. Therefore, depending on the embodiment, metal components other than the lead component can also be reduced to the sub-ppb level on a mass basis, and this production method is useful in the production of electronic materials, particularly in the production of semiconductors.

[0077] The above-mentioned method for producing an organosilicon compound is also referred to as the first method, and the method for producing an organosilicon compound shown below is also referred to as the second method. Another embodiment of the present invention is a method for producing an organosilicon compound, including a reaction step of performing a Grignard reaction using at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane, an organic halide, and magnesium to obtain a reaction solution. The manufacturing method may include processes other than the reaction process, and preferably further includes the ultraviolet irradiation process described above. As described in the first method, in the embodiment including the above reaction process, since a substance that absorbs ultraviolet rays is hardly generated, by providing an ultraviolet irradiation process or the like, an organosilicon compound with a small lead component as an impurity can be obtained. For the reaction process in the second method, the conditions of the reaction process described in the first method can be similarly applied, and for the processes other than these, each process in the first method can be similarly applied.

Example

[0078] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0079] The experimental methods and evaluation methods in the examples and comparative examples are as follows.

[0080] <Evaluation> [Evaluation of Lead Concentration] 1 mL of the liquid obtained in the examples or comparative examples described later was added to a container made of Teflon (registered trademark), the container was placed on a hot plate and heated at 130 to 150 °C to volatilize the organic solvent. Then, 1 mL of ultrapure water, 3 mL of nitric acid (60% by mass), and 2 mL of hydrofluoric acid (50% by mass) were dropped, and heating was performed again at 180 °C for wet digestion. Then, heating was continued until dryness. After repeating wet digestion and drying until the organosilicon compound was completely decomposed, the remaining lead component was recovered with 0.2 mL of nitric acid (60%), and the solution made up to 20 mL was used as the measurement solution. The lead (Pb) concentration (mass%) in the measurement solution was quantified by ICP-MS (ICP-MS7900 manufactured by Agilent Technologies). The evaluation results are shown in Table 3 below.

[0081] <Synthesis of Organosilicon Compound> [Example 1] After putting 32.7 g of magnesium particles and 0.56 L of tetrahydrofuran into a reaction flask, a mixed solution containing 129.2 g of 1,3-dibromopropane, 78.2 g of trimethoxysilane, and 0.12 L of tetrahydrofuran (in a total of 314.2 g of tetrahydrofuran solution, the concentration of 1,3-dibromopropane is 41% by weight, and the concentration of trimethoxysilane is 25% by weight) was gradually added to obtain a reaction solution containing an organosilicon compound represented by the following formula (7) (weight average molecular weight measured by GPC is 500 - 600, dispersity is 1.15 - 1.25). The obtained reaction solution was a colorless and transparent solution in which the organosilicon compound and magnesium salt were dissolved. The content of the organosilicon compound in the reaction solution was 5.3% by weight. Also, the ratio of the total amount of alkoxysilane used (mol) to the total amount of solvent used (L) was 0.94 mol / L, and the ratio of the total amount of halogen groups contained in the total amount of organic halides used (mol) to the total amount of alkoxy groups contained in the total amount of alkoxysilanes used (mol) was 0.67 mol / mol, and the ratio of the total amount of metallic magnesium used (mol) to the total amount of halogen groups contained in the total amount of organic halides used (mol) was 1.05 mol / mol. Thereafter, liquid separation was performed using an aqueous oxalic acid solution to dissolve and remove the magnesium salt in the aqueous layer. A colorless and transparent solution containing the organosilicon compound in the organic layer was obtained. Using the obtained solution, ultraviolet irradiation (ultraviolet intensity 3,000 mW / cm 2 ; integrated light quantity 10.8 kJ / cm 2 ) was performed for 1 hour using an ultraviolet irradiation device (manufactured by SEN Special Light Source Co., Ltd.; reaction vessel VG300; water-cooled jacket JV-1Q; lamp UVL20PH-6, wavelength is 254 nm; power supply UVB-20C). After adsorbing residual metals using a chelating resin (manufactured by Organo Corporation; Orlite (registered trademark) DS-21) previously vacuum-dried on the irradiated solution, filtration was performed, and the obtained liquid was used to evaluate the lead (Pb) concentration.

[0082]

Chemical formula

[0083] <Synthesis of Organosilicon Compounds> [Comparative Example 1] After putting 32.7 g of magnesium particles and 0.56 L of tetrahydrofuran into a reaction flask, a solution containing 129.2 g of 1,3-dibromopropane, 86.7 g of trichlorosilane, and 0.12 L of tetrahydrofuran (in a total of 322.7 g, the concentration of 1,3-dibromopropane was 40% by weight and the concentration of trichlorosilane was 27% by weight) was gradually added to obtain a reaction solution. 129.5 g of triethylamine and 41.0 g of methanol were added to the obtained reaction solution to obtain a white-yellow slurry-like reaction solution containing the organosilicon compound represented by the above formula (7) (weight-average molecular weight measured by GPC: 550 - 650, dispersity: 1.13 - 1.20), magnesium salt, and triethylamine hydrochloride. The content of the organosilicon compound in the reaction solution was 5.1% by weight. Thereafter, liquid separation was performed using an aqueous oxalic acid solution to dissolve and remove the magnesium salt and triethylamine hydrochloride in the aqueous layer. A colorless and transparent solution containing the organosilicon compound was obtained in the organic layer. Thereafter, ultraviolet irradiation (ultraviolet intensity: 3,000 mW / cm 2 ; integrated light quantity 10.8 J / cm 2 ) was performed for 1 hour using an ultraviolet irradiation device (manufactured by SEN Special Light Source Co., Ltd.; reaction vessel VG300; water-cooled jacket JV-1Q; lamp UVL20PH-6, wavelength: 254 nm; power supply UVB-20C). Furthermore, after adsorbing residual metals using a chelating resin (manufactured by Organo Corporation; Orlite (registered trademark) DS-21) or a solid-phase resin column that had been vacuum-dried in advance to the solution after ultraviolet irradiation, filtration was performed, and the obtained liquid was used to evaluate the lead (Pb) concentration.

[0084]

Table 3

Claims

1. A reaction step of performing a Grignard reaction using at least one alkoxysilane selected from the group consisting of dialkoxysilane, trialkoxysilane, and tetraalkoxysilane, an organic halide, and magnesium to obtain a reaction solution, and An irradiation step of irradiating the reaction solution with ultraviolet light, A method for producing an organosilicon compound, comprising:

2. The ratio of the total amount (mol) of halogen groups (X) contained in the entire halide used to the total amount (mol) of alkoxy groups contained in the entire alkoxysilane used is 0.50 mol / mol or more and 8.0 mol / mol or less. The method for producing an organosilicon compound according to claim 1.

3. The method for producing an organosilicon compound according to claim 1 or 2, wherein an organic solvent is further used in the reaction step.

4. The ratio of the total amount (mol) of the alkoxysilane used to the total amount (L) of the organic solvent used is 0.10 mol / L or more and 6.0 mol / L or less. The method for producing an organosilicon compound according to claim 3.

5. The method for producing an organosilicon compound according to any one of claims 1 to 4, comprising a purification treatment for purifying the reaction solution after the irradiation step.

6. The method for producing an organosilicon compound according to any one of claims 1 to 5, comprising a liquid separation treatment of separating the reaction solution into an organic phase and an aqueous phase by mixing an aqueous solution containing an acid and the reaction solution after the reaction step and before the irradiation step.

7. The method for producing an organosilicon compound according to claim 6, wherein the acid is an acid capable of forming a salt with magnesium, and the salt is a salt insoluble in water.

8. The method for producing an organosilicon compound according to claim 7, wherein the acid is at least one acid selected from the group consisting of oxalic acid, carbonic acid, and tartaric acid.

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