JPH09157278A - Composition for producing organomonoalkoxysilane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition for producing an organomonoalkoxysilane, comprising an organodisiloxane, an orthocarboxylate ester, a compound bearing a group containing active hydrogen atoms and a catalyst and giving the organomonoalkoxysiiane cleanly in high yield under mild conditions. SOLUTION: An organodisiloxane of the formula (R<1> -R<6> are each a monofunctional hydrocarbon, H), for example, hexamethyldisiloxane, an orthocaboxylate ester such as trimethyl orthoformate, a compound bearing a group containing active hydrogens, for example, water and a catalyst such as concentrated sulfuric acid are mixed to give the objective composition which can produce an organomonoalkoxysilane of high purity in high yield cleanly under mild conditions by stirring the composition at room temperature in a nitrogen atmosphere through a halogen-free process with increased safety.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition for producing an organomonoalkoxysilane. More specifically, an organomonoalkoxysilane for decomposing an organodisiloxane for the purpose of producing an organomonoalkoxysilane which is one of important intermediates of silylating agents and various other organosilicon compounds. It relates to a composition for manufacturing.

[0002]

2. Description of the Related Art As a technique for obtaining an organomonoalkoxysilane by reacting an organodisiloxane and an orthocarboxylic acid ester compound, a reaction for obtaining trimethylethoxysilane from hexamethyldisiloxane and triethyl orthoformate in the presence of an acid catalyst is I. ． P. Zhurkina
(Metalloorg. Kh.
im. , 3,1283 (1990)). As a related technique, a method for obtaining an organomonochlorosilane from an organodisiloxane is disclosed in JP-A-52-65226 and JP-A-5-222062.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
P. The reaction reported by Zhurkina et al. Has a drawback that the reaction rate, the reaction rate, and the yield are low because there is no substance having a reaction promoting effect. That is, in the reaction of hexamethyldisiloxane and triethyl orthoformate, the conversion rate of hexamethyldisiloxane was as low as 52%, and the yield of the product trimethylethoxysilane was about 40%. Further, no study has been made on a compound having a hydrogen atom as a substituent on a silicon atom. The method disclosed in JP-A-52-65226 is a method in which an organodisiloxane and a dialkyldichlorosilane are reacted with hexamethylphosphoric triamide as a catalyst, but a viscous polysiloxane is produced as a by-product. However, there is a problem that the catalyst hexamethylphosphoric triamide has a strong carcinogenicity, and it is difficult to industrialize it. Further, in the technique disclosed in JP-A-5-222062, there is a problem that a sulfurous acid gas is produced as a by-product because an organodisiloxane is reacted with thionyl chloride. Further, when the organomonochlorosilane obtained by such a reaction is subjected to the reaction as an intermediate of various organosilicon compounds, hydrogen chloride is produced as a by-product, and there are problems in terms of safety, economy, and device corrosion. .

The present invention solves the above-mentioned problems of the prior art and decomposes organodisiloxane under mild and clean conditions to produce organomonoalkoxysilane in high yield and for producing organomonoalkoxysilane. It is intended to provide a composition.

[0005]

The composition for producing an organomonoalkoxysilane of the present invention, which has been made to achieve this object, comprises an organodisiloxane, an orthocarboxylic acid ester compound, an active hydrogen group-containing compound, and a catalyst. It is composed of a mixture. The organodisiloxane which is one of the compositions of the present invention has the formula (1)

[0006]

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[0007] In the above formula, R ¹ to R ⁶ are the same or different monovalent hydrocarbon groups, monovalent substituted hydrocarbon groups, or hydrogen atoms. In the case of a monovalent hydrocarbon group,
It may be a saturated group or an unsaturated group, and may be acyclic or cyclic. Examples thereof include various alkyl groups, alkenyl groups, vinyl groups, allyl groups, aryl groups and aralkyl groups. In the case of a monovalent substituted hydrocarbon group, examples of the substituent include a halogen atom, a cyano group, a carboxyl group and a silyl group. Further, these hydrocarbon groups may be bonded to each other to form a ring-shaped body containing a silicon atom. Various substituents may be bonded to the cyclic hydrocarbon group, an unsaturated bond may be contained, or the aromatic ring may be condensed.

Examples of such organodisiloxane include 1,1,3,3-tetramethyldisiloxane, 1,3-dimethyl-1,1,3,3-tetraphenyldisiloxane and 1,3- Bis (2-cyanoethyl)-
1,1,3,3-tetramethyldisiloxane, 1,3-
Bis (2-phenylethyl) -1,1,3,3-tetraphenyldisiloxane, 1,3-di-tert-butyl-1,3-dimethyldisiloxane, tert-butyl-
Pentamethyldisiloxane, hexamethyldisiloxane, 1,3-diisopropyl-1,1,3,3-tetramethyldisiloxane, 1,3-dicyclohexyl-1,
1,3,3-tetramethyldisiloxane, 1,3-divinyl-1,1,3,3-tetraethyldisiloxane,
1,3-diallyl-1,3-diethyl-1,3-dimethyldisiloxane, 1,3-di (3-trifluoropropyl) -1,1,3,3-tetramethyldisiloxane, di (silacyclo) Butyl) ether (formula 2),

[0009]

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Examples thereof include, but are not limited to: These organodisiloxanes may be used alone or in combination of two or more compounds. The orthocarboxylic acid ester compound which is the composition of the present invention, trimethyl orthoformate, triethyl orthoformate, tripropyl orthoformate, tributyl orthoformate, orthoformate compounds such as trioctyl orthoformate, trimethyl orthoacetate, triethyl orthoacetate, Examples thereof include orthoacetic acid ester compounds such as tripropyl orthoacetate, tributyl orthoacetate, and trioctyl orthoacetate, but are not limited thereto. These orthocarboxylic acid ester compounds may be used alone or in combination of two or more kinds. Among these orthocarboxylic acid ester compounds, the orthocarboxylic acid methyl ester or the orthocarboxylic acid ethyl ester is preferable in that the alkoxy group of the resulting organomonoalkoxysilane is a highly versatile methoxy group or an ethoxy group. Orthoformate is preferable in terms of high reactivity. Further, methyl orthoformate is particularly preferable in that it easily produces a low boiling point methyl formate as a by-product and is easily available.

The amount of the orthocarboxylic acid ester compound to be mixed is not particularly limited, but the amount is preferably 10 to 100,000 mol, and more preferably 50 to 10,000 mol per 100 mol of the organodisiloxane. The active hydrogen group-containing compound which is the composition of the present invention, a hydroxyl group in the molecule, a carboxyl group, a mercapto group,
A compound containing an amino group or the like and a compound which reacts with an orthocarboxylic acid ester compound to form a compound containing a hydroxyl group, a carboxyl group, a mercapto group, an amino group or the like in the molecule. Specific examples thereof include water, alcohol compounds, carboxylic acid compounds, thiol compounds, amine compounds, and the like, and water and alcohol compounds are preferable in that the reaction rate is high. The active hydrogen group-containing compound also includes, for example, water and alcohol contained as impurities in the starting material.

When an alcohol compound is used as the active hydrogen group-containing compound, the alcohol compound is
Examples are monohydric aliphatic alcohols such as methanol, ethanol, isopropanol, n-propanol and n-butanol, aromatic alcohols such as benzyl alcohol, phenol and naphthyl alcohol, and polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin. However, the present invention is not limited to these. It is preferable to use an alcohol having the same organic group moiety as the orthocarboxylic acid ester compound used in these, because the resulting organomonoalkoxysilane has a single alkoxy group, and for example, as an orthocarboxylic acid ester compound, trimethyl orthoformate is used. When is used, methanol is preferred.

When a carboxylic acid compound is used as the active hydrogen group-containing compound, examples of the carboxylic acid compound include, but are not limited to, formic acid, acetic acid, propanoic acid, acrylic acid and benzoic acid. . When using a thiol compound as an active hydrogen group-containing compound,
Examples of the thiol compound include methanethiol, ethanethiol, 1-propanethiol, 2-propanethiol, 1-butanethiol, thiophenol, and 1,2-ethanedithiol, but are not limited thereto. .

When an amine compound is used as the active hydrogen group-containing compound, examples of the amine compound include ammonia, methylamine, dimethylamine, ethylamine, diethylamine, aniline and ammonium chloride, but are not limited thereto. is not. These active hydrogen group-containing compounds may be used alone or in combination of two or more. The mixing amount of the active hydrogen group-containing compound used in the present invention is not particularly limited, but since the reaction rate increases as the usage amount increases, it becomes 0.1 mol or more per 100 mol of organodisiloxane based on active hydrogen groups. The amount is preferable, and the amount of 1 mol or more is particularly preferable. When no active hydrogen group-containing compound is used, the reaction does not proceed or is extremely slow,
Further, the reaction rate of the organodisiloxane becomes low, and the yield of the organomonoalkoxysilane becomes low. However, if the amount used is too large, it will be difficult to separate the product. Therefore, 100,000 based on active hydrogen groups per 100 mol of disiloxane.
An amount of not more than mol is preferable, and an amount of not more than 10,000 mol is particularly preferable. Regarding the active hydrogen group-containing compound, the concentration in the solution depends on the reaction rate. For this reason, the concentration of the active hydrogen group-containing compound used in the mixture is 0.
1 to 80% by weight is preferable, and 1 to 50% by weight is particularly preferable.

Examples of the catalyst used in the present invention include hydrochloric acid, sulfuric acid, fuming sulfuric acid, nitric acid, acetic acid, phosphoric acid, phosphoric acid ester, sulfurous acid, nitrous acid, hypochlorous acid, perchloric acid, hydrogen peroxide and benzoic acid. Acid, salicylic acid, boric acid, trifluoroacetic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, p-phenolsulfonic acid, trialkylsilyltrifluoromethanesulfonic acid, trialkylsilylperchlorate, bistrimethylsilyl sulfate,
Examples thereof include strong acid ion exchange resins (for example, Nafion (trade name)), chloroplatinic acid, aluminum chloride, iron chloride, boron trifluoride, activated clay and the like, but are not limited thereto. These catalysts may be used alone or in combination of two or more. Acid catalysts are preferred in terms of reactivity, and sulfonic acid compounds such as sulfuric acid, trifluoromethanesulfonic acid and p-toluenesulfonic acid are particularly preferred.

The mixing amount of the catalyst used in the present invention is not particularly limited, but is 0.0 per 100 parts by weight of disiloxane.
01 to 20 parts by weight is preferable, and 0.01 to 5 parts by weight is particularly preferable. The concentration of the catalyst used in the present invention in the mixed solution is not particularly limited, but 0.0001 to 20% by weight is preferable, and 0.01 to 5% by weight is preferable because the catalyst concentration in the reaction solution depends on the reaction rate. Particularly preferred.

A solvent may be used to mix the composition of the present invention. As the solvent, a compound that is inert to the orthocarboxylic acid ester compound and the monoalkoxysilane and is liquid at the reaction temperature can be used.
For example, aromatic hydrocarbon compounds such as pentane, hexane, heptane, octane, nonane, decane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, benzene, toluene, xylene, mesitylene, ethylbenzene, naphthalene, biphenyl, diphenylmethane, etc. Group hydrocarbon compounds, organic halides such as dichloromethane, chloroform, methyl chloride, 1,2-dichloroethane, dibromomethane, bromoform and methyl bromide, ether compounds such as diethyl ether, diphenyl ether, 1,4-dioxane and tetrahydrofuran, Examples thereof include ketone compounds such as acetone and methyl ethyl ketone, and carbon disulfide, but are not limited thereto. In addition, the organodisiloxane, orthocarboxylic acid ester compound, or active hydrogen group-containing compound which is the composition of the present invention may be used as a solvent. These solvents may be used alone or as a mixture of two or more kinds.

The amount of the solvent used in the present invention is not particularly limited, but is 0.1 per 100 parts by weight of disiloxane.
The amount of 100 to 100,000 parts by volume is preferable, and 10 to 10
An amount of 000 parts by volume is particularly preferable. The organomonoalkoxysilane is obtained by reacting the mixture of the composition of the present invention, the organodisiloxane, the orthocarboxylic acid ester compound, the active hydrogen group-containing compound, and the catalyst. A reaction formula (Formula 3) is shown.

[0019]

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In the above formula, R ¹ to R ⁶ and R ′ are the same or different monovalent hydrocarbon groups, monovalent substituted hydrocarbon groups or hydrogen atoms, and R is the same or different monovalent hydrocarbon groups. Or a monovalent substituted hydrocarbon group.
In the case of a monovalent hydrocarbon group, it may be a saturated group or an unsaturated group, and may be acyclic or cyclic. For example, various alkyl groups, alkenyl groups, vinyl groups, allyl groups,
Examples thereof include an aryl group and an aralkyl group. In the case of a monovalent substituted hydrocarbon group, examples of the substituent include a halogen atom, a cyano group, a carboxyl group and a silyl group. Regarding R ¹ to R ⁶ , these hydrocarbon groups may be bonded to each other to form a ring-shaped body containing a silicon atom. Various substituents may be bonded to the cyclic hydrocarbon group, an unsaturated bond may be contained, or the aromatic ring may be condensed.

Specific examples of the organomonoalkoxysilane obtained by the above reaction include dimethylmethoxysilane, diphenylmethylmethoxysilane, (2-cyanoethyl) dimethylmethoxysilane, (2-phenylethyl) diphenylmethoxysilane and tert. -Butylmethylmethoxysilane, tert-butyldimethylethoxysilane, trimethylmethoxysilane, isopropyldimethylmethoxysilane, cyclohexyldimethylmethoxysilane, diethylvinylethoxysilane, allylethylmethylmethoxysilane, dimethyltrifluoropropylmethoxysilane, 1-methoxysilacyclobutane ,
Examples thereof include dimethylethoxysilane, trimethylpropoxysilane and triphenylethoxysilane.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The method for preparing the composition of the present invention and the reaction procedure for producing a monoalkoxysilane using the composition of the present invention may be carried out, for example, as follows. An organodisiloxane, an orthocarboxylic acid ester compound, an active hydrogen group-containing compound, and a catalyst are mixed to prepare a mixed solution. The reaction proceeds from the time when the last one of these four types of compounds is added. When mixing, the order of addition is arbitrary, but when a strongly acidic catalyst such as sulfuric acid is used as a catalyst, heat generation may occur, so it is preferable to add the catalyst slowly at the end. In order to make the mixing of each component more effective, stirring, shaking, or a solvent can be used. Since the reaction proceeds rapidly even at room temperature, there is no particular need for heating, but there is no problem even if heating is performed to increase the reaction rate. The amount of the orthocarboxylic acid ester compound used is not particularly limited, but is preferably 10 to 100,000 mol, and particularly preferably 50 to 10,000 mol per 100 mol of organodisiloxane. The amount of the active hydrogen group-containing compound used is not particularly limited, but is preferably 0.1 to 10000 mol, and more preferably 1 to 500 mol, based on 100 mol of the organodisiloxane. The concentration of the active hydrogen group-containing compound in the reaction solution is not particularly limited, but is preferably 0.1 to 80% by weight, particularly preferably 1 to 50% by weight. The amount of the catalyst used in the present invention is not particularly limited, but is preferably 0.001 to 20 parts by weight, and 0.01 to 5 parts by weight based on 100 parts by weight of the organodisiloxane.
Part by weight is particularly preferred. The concentration of the catalyst used in the present invention in the reaction solution is not particularly limited, but 0.0001 to 20
% By weight is preferred, and 0.01 to 5% by weight is particularly preferred. The amount of the solvent used in the present invention is not particularly limited, but it is 1 to 1 with respect to 100 parts by weight of the organodisiloxane.
00000 parts by volume is preferable, and 10 to 10,000 parts by volume is particularly preferable. The reaction temperature is not particularly limited, but is 0 to
500 degreeC is preferable and 10-200 degreeC is especially preferable.

A crude product of an organomonoalkoxysilane is obtained by the above reaction. To obtain a high-purity monoalkoxysilane from the obtained crude product, the crude product may be distilled. Unreacted organodisiloxane, orthocarboxylic acid ester compound, active hydrogen group-containing compound, catalyst, and solvent can be returned to the reaction vessel and recycled. These do not particularly need to be separated and purified.

By using the composition for producing organomonoalkoxysilane of the present invention, the organodisiloxane decomposition reaction proceeds rapidly even at room temperature. The reaction can be performed under mild conditions without using a dangerous reaction product, hydrogen chloride or chlorosilane is not produced as a by-product, and an undesirable compound is hardly formed. No complicated fractional distillation operation is required in the reaction step. That is, by using the composition of the present invention, it is possible to produce an organomonoalkoxysilane cleanly in a halogen-free process under relatively mild conditions and in a high yield.

[0025]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples. (Examples 1 to 5) Hexamethyldisiloxane, trimethyl orthoformate, an active hydrogen group-containing compound, and concentrated sulfuric acid were mixed in a 50 mL eggplant-shaped flask, and the mixture was stirred at room temperature under a nitrogen atmosphere with a reflux condenser. As the active hydrogen group-containing compound, water (Example 1), methanol (Example 2),
Ethanol (Example 3), 1-butanol (Example 4), and acetic acid (Example 5) were used. 1H-NM
R measurement was performed to determine the yield of methoxytrimethylsilane on the basis of hexamethyldisiloxane. Table 1 shows the amount of raw material charged and the yield of methoxytrimethylsilane.

[0026]

[Table 1]

Comparative Example 1 The reaction was carried out in exactly the same manner as in Examples 1 to 5 except that the active hydrogen group-containing compound was not added. 1H-NMR measurement was performed and the yield of methoxytrimethylsilane was determined on the basis of hexamethyldisiloxane. Table 1 shows the amount of raw material charged and the yield of methoxytrimethylsilane. (Examples 6 to 8) Orthocarboxylic acid ester, methanol, and sulfuric acid were mixed in a 5 mL volumetric flask. Hexamethyldisiloxane was added thereto, chloroform was further added as a solvent, and the mixture was shaken to obtain a solution having a total volume of 5 mL. Trimethyl orthoformate (Example 6), triethyl orthoformate (Example 7), and trimethyl orthoacetate (Example 8) were used as orthocarboxylic acid esters. These reaction solutions were allowed to stand at room temperature and 1H-NMR was performed.
The measurement was performed and the yield of methoxytrimethylsilane was determined on the basis of hexamethyldisiloxane. Table 2 shows the amount of raw material charged and the yield of methoxytrimethylsilane.

[0028]

[Table 2]

(Comparative Example 2) Methanol 24 mg (0.74 mmol) and sulfuric acid 21 mg were placed in a 5 mL volumetric flask.
(0.21 mmol) was weighed, and 1.21 g (7.42 mmol) of hexamethyldisiloxane was added. Chloroform was added to make the total volume of the solution 5 mL, and the mixture was shaken and then left standing at room temperature. 1H-NMR measurement was performed 5 hours later, but 100% of hexamethyldisiloxane remained. Example 9 7.90 g of trimethyl orthoformate (74.
5 mmol), 1.10 g of methanol (34.3 mmo)
l) and sulfuric acid 20 mg (0.20 mmol) were weighed in a 50 mL two-necked flask containing a magnetic stirrer, equipped with a reflux condenser, and stirred under a nitrogen atmosphere while stirring 1,1,3,3-tetramethyldisiloxane. 10.0 g (74.5 mmo
l) was added. After stirring for 30 minutes at room temperature, 1H-NM
When R measurement was performed, it was found that dimethylmethoxysilane was 1,
Yield 98 based on 1,3,3-tetramethyldisiloxane
%.

[0030]

INDUSTRIAL APPLICABILITY As described above in detail, by using the composition for producing an organomonoalkoxysilane of the present invention, it is possible to obtain a monoalkoxysilane in a high yield and a high purity by a halogen-free process. It has high properties and can be easily separated and purified. In addition, since the reaction proceeds even at room temperature, equipment costs and manufacturing costs can be kept low.

Claims (10)

[Claims] 1. A composition for producing an organomonoalkoxysilane, which comprises a mixture of an organodisiloxane, an orthocarboxylic acid ester compound, an active hydrogen group-containing compound, and a catalyst. 2. An organodisiloxane represented by the general formula (1): (R ¹ to R ⁶ are the same or different monovalent hydrocarbon groups,
The composition for producing an organomonoalkoxysilane according to claim 1, which contains an organodisiloxane represented by a monovalent substituted hydrocarbon group or a hydrogen atom). 3. The composition for producing an organomonoalkoxysilane according to claim 1, which is mixed using a solvent. 4. The organodisiloxane contains an organodisiloxane having at least one hydrogen atom as a substituent on silicon.
The composition for producing an organomonoalkoxysilane according to 1. 5. The composition for producing an organomonoalkoxysilane according to claim 1, wherein the orthocarboxylic acid ester compound is orthocarboxylic acid methyl ester. 6. The composition for producing an organomonoalkoxysilane according to claim 1, wherein the orthocarboxylic acid ester compound is an orthoformate ester. 7. The composition for producing an organomonoalkoxysilane according to claim 1, wherein the catalyst is an acid catalyst. 8. The composition for producing an organomonoalkoxysilane according to claim 1, wherein a compound which reacts with an orthocarboxylic acid ester compound to produce an alcohol is used as the active hydrogen group-containing compound. 9. The composition for producing an organomonoalkoxysilane according to claim 1, wherein the active hydrogen group-containing compound is water and / or alcohol. 10. A composition for producing an organomonoalkoxysilane, which comprises an organodisiloxane, methyl orthoformate, methanol, and an acid catalyst.