JP6665437B2 - Method for producing tertiary alkyl silane and tertiary alkyl alkoxy silane - Google Patents

Description

  The present invention relates to a method for producing a tertiary alkylsilane and a tertiary alkylalkoxysilane.

  In a method for producing a tertiary alkylsilane represented by t-butylsilanes, a reaction between alkyllithium and chlorosilane is generally well known. This method has a problem that the cost of alkyl lithium is high. Therefore, there is a need for a production method using a less expensive Grignard reagent. It is known that in the reaction of a tertiary alkyl Grignard reagent with chlorosilane, the reaction proceeds by adding a catalytic amount of ions such as CN, SCN, and NCS (see Non-Patent Document 1). However, CN ions are liable to form highly toxic compounds, and there is a major problem in use and disposal in the production process. Further, SCN ions and NCS ions have sulfur remaining in the product, and the odor becomes a serious problem in product quality. In addition, it is known that the reaction proceeds even when copper halide is used as a catalyst (see Patent Document 1). However, according to the examples in the patent document and the follow-up test by the inventor of the present application (see Comparative Examples), the synthesis method according to the method of the document does not produce the target product sufficiently efficiently.

  Tertiary alkylsilanes are general-purpose compounds and are used as various known chemical products and intermediates. For example, a tertiary alkylalkoxysilane can be produced by reacting a corresponding tetraalkoxysilane with an alkyl lithium. This method has a problem that the cost of alkyllithium is high as in the above-mentioned method for producing a tertiary alkylsilane (see Patent Document 2). The tertiary alkylalkoxysilane can also be synthesized by reacting a tertiary alkylsilane having a Si—Cl bond with an alcohol. Tertiary alkylalkoxysilanes are used, for example, as silicon-containing polymer precursors, silicon-containing thin film precursors, functional group protecting reagents, coating agents, silane coupling agents, silica particle precursors, surface modifiers, and the like. .

JP-A-7-157491 Patent No. 4863182

Patrick, J .; L. David, P .; M. Quentin, E .; T. Organometallics, 1989, 8, 1121.

  An object of the present invention is to provide an efficient method for producing a tertiary alkyl silane using an inexpensive material, and further provide a tertiary alkyl silane having a Si—Cl bond thus produced. An object of the present invention is to provide a method for producing a tertiary alkylalkoxysilane used.

  The present inventors have conducted intensive studies to solve the above problems, and as a result, in the reaction of a tertiary alkyl Grignard reagent with chlorosilane, the reaction is carried out at a low temperature in the coexistence of a catalyst, so that the tertiary alkyl is efficiently used. It has been found that a silane can be produced, and furthermore, a tertiary alkylalkoxysilane can be produced by reacting the tertiary alkylsilane having a Si—Cl bond thus produced with an alcohol. This led to the completion of the present invention.

  That is, the present invention relates to a method for producing a tertiary alkylsilane, which comprises reacting a tertiary alkyl Grignard reagent with chlorosilane at -130 ° C to -20 ° C in the presence of copper halide.

  Furthermore, the present invention relates to a method for producing a tertiary alkylalkoxysilane, which comprises reacting the tertiary alkylsilane having a Si—Cl bond produced as described above with an alcohol.

  Hereinafter, the present invention will be described in detail.

  First, a method for producing a tertiary alkylsilane in which a tertiary alkyl Grignard reagent and chlorosilane are reacted at −130 ° C. to −20 ° C. in the presence of copper halide will be described.

  Examples of the tertiary alkyl Grignard reagent include t-butyl magnesium halide, t-pentyl magnesium halide, 1,1-dimethyl-2-propenyl magnesium halide, 1,1,2-trimethylpropyl magnesium halide, and 1-methylcyclopentyl magnesium halide. , Texyl magnesium halide, 1-adamantyl magnesium halide and the like. Particularly, t-butylmagnesium halide is preferred in terms of good reaction efficiency. The halogen compound used as the halide is not particularly limited, and examples thereof include fluorine, chlorine, bromine, and iodine. Particularly, chlorine and bromine are preferable in terms of easy handling. Specific tertiary Grignard reagents include t-butylmagnesium fluoride, t-butylmagnesium chloride, t-butylmagnesium bromide, t-butylmagnesium iodide, t-pentylmagnesium chloride, t-pentylmagnesium bromide, 1-dimethyl-2-propenylmagnesium chloride, 1,1-dimethyl-2-propenylmagnesium bromide, 1,1,2-trimethylpropylmagnesium chloride, 1,1,2-trimethylpropylmagnesium bromide, 1-methylcyclopentylmagnesium chloride , 1-methylcyclopentyl magnesium bromide, texyl magnesium chloride, texyl magnesium bromide, 1-adamantyl magnesium chloride, 1-adamantyl magnesium And t-butylmagnesium chloride, t-butylmagnesium bromide, t-pentylmagnesium bromide and the like are particularly preferable in terms of good reaction efficiency, and t-butylmagnesium chloride and t-butylmagnesium chloride are preferable. Butylmagnesium bromide is particularly preferred. These tertiary alkyl Grignard reagents can be prepared by a general method such as a reaction of magnesium with a corresponding tertiary alkyl halide, or commercially available ones can be used as they are.

  As chlorosilane, in addition to tetrachlorosilane, silicon may have a substituent other than 1 to 3 chlorine atoms. Trichlorosilane, methyltrichlorosilane, methyldichlorosilane, ethyltrichlorosilane, vinyltrichlorosilane, phenyltrichlorosilane Chlorosilane, phenyldichlorosilane, methylphenyldichlorosilane, trimethylchlorosilane and the like can be exemplified.

  Examples of the copper halide include copper (I) chloride, copper (II) chloride, copper (I) bromide, copper (II) bromide, and copper (I) iodide. Copper (I), copper (I) bromide, and copper (I) iodide are preferred, and copper (I) chloride is particularly preferred, in terms of high reaction yield, low cost and easy availability.

  The tertiary alkyl silane obtained by the production method of the present invention includes t-butyltrichlorosilane, t-butyldichlorosilane, t-butylmethyldichlorosilane, t-butylmethylchlorosilane, t-butylethyldichlorosilane, t-butylethyldichlorosilane, Butylvinyldichlorosilane, t-butylphenyldichlorosilane, t-butylphenylchlorochlorosilane, t-butylmethylphenylchlorosilane, t-butyltrimethylsilane, t-pentyltrichlorosilane, t-pentyldichlorosilane, t-pentylmethyldichlorosilane, t-pentylmethylchlorosilane, t-pentylethyldichlorosilane, t-pentylvinyldichlorosilane, t-pentylphenyldichlorosilane, t-pentylphenylchlorosilane, t-pentylmethylphenylchlorosilane , T-pentyltrimethylsilane, 1,1-dimethyl-2-propenyltrichlorosilane, 1,1-dimethyl-2-propenyldichlorosilane, 1,1-dimethyl-2-propenylmethyldichlorosilane, 1,1-dimethyl- 2-propenylmethylchlorosilane, 1,1-dimethyl-2-propenylethyldichlorosilane, 1,1-dimethyl-2-propenylvinyldichlorosilane, 1,1-dimethyl-2-propenylphenyldichlorosilane, 1,1-dimethyl -2-propenylphenylchlorosilane, 1,1-dimethyl-2-propenylmethylphenylchlorosilane, 1,1-dimethyl-2-propenyltrimethylsilane, 1,1,2-trimethylpropyltrichlorosilane, 1,1,2-trimethyl Propyldichlorosilane, 1,1 2-trimethylpropylmethyldichlorosilane, 1,1,2-trimethylpropylmethylchlorosilane, 1,1,2-trimethylpropylethyldichlorosilane, 1,1,2-trimethylpropylvinyldichlorosilane, 1,1,2-trimethyl Propylphenyldichlorosilane, 1,1,2-trimethylpropylphenylchlorosilane, 1,1,2-trimethylpropylmethylphenylchlorosilane, 1,1,2-trimethylpropyltrimethylsilane, 1-methylcyclopentyltrichlorosilane, 1-methylcyclopentyl Dichlorosilane, 1-methylcyclopentylmethyldichlorosilane, 1-methylcyclopentylmethylchlorosilane, 1-methylcyclopentylethyldichlorosilane, 1-methylcyclopentylvinyldichloro Silane, 1-methylcyclopentylphenyldichlorosilane, 1-methylcyclopentylphenylchlorosilane, 1-methylcyclopentylmethylphenylchlorosilane, 1-methylcyclopentyltrimethylsilane, texyltrichlorosilane, texyldichlorosilane, texylmethyldichlorosilane, texylmethyl Chlorosilane, Texylethyldichlorosilane, Texylvinyldichlorosilane, Texylphenyldichlorosilane, Texylphenylchlorosilane, Texylmethylphenylchlorosilane, Texyltrimethylsilane, 1-adamantyltrichlorosilane, 1-adamantyldichlorosilane, 1- Adamantylmethyldichlorosilane, 1-adamantylmethylchlorosilane, 1-adamantylethyldichlorosilane, -Adamantylvinyldichlorosilane, 1-adamantylphenyldichlorosilane, 1-adamantylphenylchlorosilane, 1-adamantylmethylphenylchlorosilane, 1-adamantyltrimethylsilane, and the like, and in terms of high reaction efficiency, particularly t-butyltrichlorosilane, t-butylmethylchlorosilane, t-butylethyldichlorosilane, t-pentyltrichlorosilane, 1,1,2-trimethylpropyltrichlorosilane are preferred, t-butyltrichlorosilane, t-butylmethylchlorosilane, t-butylethyldicyclolosilane Is more preferable, and t-butyltrichlorosilane is particularly preferable.

  As a typical example of the production of a tertiary alkylsilane according to the method of the present invention, a tertiary alkyl Grignard reagent is prepared by adding the above-mentioned chlorosilane to a copper halide and stirring the mixture at a low temperature. After the addition, the mixture is aged while gradually returning the temperature to around room temperature.

  The mixture of chlorosilane and copper halide, and the tertiary alkyl Grignard reagent may be diluted with a solvent. The solvent used is not particularly limited as long as it does not react with the used chlorosilane, copper halide and tertiary alkyl Grignard reagent, and tetrahydrofuran, diethyl ether, dibutyl ether, 1,2-dimethoxyethane, pentane, hexane, heptane, octane, Toluene, xylene, triethylamine and the like can be used. These solvents may be used alone or as a mixture.

  The gas that can be used as the atmosphere during the reaction process is not particularly limited as long as it does not react with the chlorosilane, copper halide and tertiary alkyl Grignard reagent used, and examples thereof include dry air, nitrogen, helium, neon, and argon. be able to.

  The ratio of the chlorosilane to the tertiary alkyl Grignard reagent is not particularly limited, and is preferably 0.5 to 1.5 molar equivalents, more preferably 0.8 to 1 molar equivalent with respect to chlorosilane, in that the reaction proceeds efficiently. .2 molar equivalents are particularly preferred.

  The amount of copper halide to be added is not particularly limited, and from the viewpoint that the reaction proceeds efficiently, 0.01 molar equivalent to 1 molar equivalent relative to chlorosilane is preferable, and 0.01 molar equivalent to 0.1 molar equivalent is preferable. Particularly preferred.

  The rate at which the tertiary alkyl Grignard reagent is added is not particularly limited, and is preferably 10 minutes to 24 hours from the viewpoint of maintaining a low temperature and efficiently proceeding the reaction.

  The reaction temperature is from -130C to -20C. When the reaction temperature is high, undesirable side reactions occur and the synthesis efficiency is reduced. The temperature is particularly preferably from -80 ° C to -20 ° C in that the desired reaction proceeds quickly while sufficiently suppressing side reactions.

  The reaction time is not particularly limited, and is preferably 0.5 hours to 24 hours, more preferably 1 hour to 12 hours, particularly preferably 2 hours to 6 hours, from the viewpoint of completing the reaction sufficiently.

  There is no particular limitation on the time until the temperature is returned to around room temperature after completion of the addition, and 10 minutes to 24 hours are preferable, and 1 hour to 18 hours is preferable in that side reactions are suppressed and the treatment can be performed promptly. More preferably, 2 hours to 12 hours are particularly preferable.

After the completion of the reaction is confirmed by a method such as ¹ H NMR or gas chromatography, the obtained tertiary alkylsilane is obtained by a general method such as filtration, solvent distillation, or distillation. It can be purified. In addition, various compounds having a tertiary alkylsilyl group can be synthesized by further using the obtained reaction solution or a tertiary alkylsilane obtained by purifying the reaction solution for the reaction.

  Next, a method for producing a tertiary alkylalkoxysilane by reacting the tertiary alkylsilane obtained by the production method of the present invention with an alcohol will be described.

  There is no particular limitation on the alcohol used, and an alcohol corresponding to the alkylchlorosilane to be produced can be used arbitrarily. Alkyl alcohols having 1 to 3 carbon atoms are preferred from the viewpoint of good reaction efficiency, and methanol or ethanol is particularly preferred.

  By adding a base such as triethylamine or pyridine to the alcohol in advance, the acid generated by the reaction between the tertiary alkylchlorosilane and the alcohol can be neutralized, and the reaction can proceed efficiently.

  As a typical example of the production of a tertiary alkylalkoxysilane according to the method of the present invention, the tertiary alkylsilane having a Si—Cl bond produced as described above is added to an alcohol, and after the addition is completed. Aged while stirring.

  The tertiary alkyl silane and the alcohol may be diluted with a solvent. The solvent used is not particularly limited as long as it does not react with the tertiary alkylsilane or alcohol used, and tetrahydrofuran, diethyl ether, dibutyl ether, 1,2-dimethoxyethane, 1,4-dioxane, pentane, hexane, heptane, octane , Toluene, xylene, triethylamine and the like can be used. These solvents may be used alone or as a mixture.

  The amount of the alcohol to which the tertiary alkylsilane is added is not particularly limited. From the viewpoint that the reaction proceeds efficiently, 0.1 to 50 molar equivalents relative to the Si—Cl bond contained in the tertiary alkylsilane is used. Preferably, 1 to 10 molar equivalents are more preferred, and 1 to 3 molar equivalents are particularly preferred.

  The addition time of the alkylsilane is not particularly limited, and is preferably from 10 minutes to 48 hours, more preferably from 30 minutes to 6 hours, from the viewpoint of obtaining a desired reaction with good selectivity.

  The reaction temperature is not particularly limited, and is preferably from -130C to 200C. Further, the temperature may be changed as needed during the addition or aging of the alkylsilane.

  The aging time is not particularly limited, and is preferably 30 minutes to 48 hours, more preferably 1 hour to 24 hours, from the viewpoint that the desired reaction proceeds sufficiently. It is particularly preferred that the reaction temperature during aging is higher than during the addition of the alkylsilane.

After the completion of the reaction is confirmed by a method such as ¹ H NMR or gas chromatography, the obtained tertiary alkylalkoxysilane is obtained by a general method such as filtration, solvent distillation, or distillation. Can be purified.

  The tertiary alkyl silane obtained by the production method of the present invention is reacted with an alcohol. Examples of the tertiary alkyl alkoxy silane include t-butyltrimethoxysilane, t-butyltriethoxysilane, and t-butyltriisosilane. Propoxy silane, t-pentyl trimethoxy silane, t-pentyl triethoxy silane, t-pentyl triisopropoxy silane, and the like are mentioned, and particularly, t-butyl triethoxy silane, t-pentyl triethoxy silane is preferable in terms of high reaction efficiency. And t-butyltriethoxysilane is particularly preferred.

  By using the production method of the present invention, a tertiary alkylsilane can be efficiently produced using an inexpensive material. Further, a tertiary alkylalkoxysilane can be produced from the tertiary alkylsilane having a Si—Cl bond and an alcohol thus produced.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 (Production of t-butyltrichlorosilane)
8.11 g (47.7 mmol) of tetrachlorosilane and 0.150 g (1.51 mmol) of copper (I) chloride were mixed with 42.8 g of tetrahydrofuran, and cooled with a mixed refrigerant of dry ice and methanol (-72 ° C). To this, 24 mL (48 mmol) of 2.0 M t-butylmagnesium chloride was added dropwise over 40 minutes. The mixture was stirred for 4 hours while maintaining the refrigerant temperature, and further stirred for 2 hours while returning the temperature to 10 ° C. The obtained mixture was analyzed by ¹ H NMR, and the yield was calculated using tetrahydrofuran as an internal standard. As a result, t-butyltrichlorosilane was 90% and bis (t-butyl) dichlorosilane was 2%.

Example 2 (Production of t-butyltriethoxysilane)
7.43 g (38.8 mmol) of t-butyltrichlorosilane obtained in Example 1 was added to a mixed solution of 10.7 g (232 mmol) of ethanol and 11.9 g (118 mmol) of triethylamine at 23 to 26 ° C. over 21 minutes. After the dropwise addition, the mixture was heated under reflux for 3 hours. When the obtained mixture was analyzed by ¹ H NMR and gas chromatography, only t-butyltriethoxysilane was observed as the silicon compound.

Example 3 (Production of t-pentyltrichlorosilane)
5.92 g (34.8 mmol) of tetrachlorosilane and 0.367 g (3.71 mmol) of copper (I) chloride were mixed with 27.1 g of tetrahydrofuran, and cooled to −40 ° C. using a cooler. To this, 18 mL (27 mmol) of 1.5 M t-pentylmagnesium bromide was added dropwise over 36 minutes. The mixture was stirred for 277 minutes while maintaining the temperature of the refrigerant, further stirred for 3.5 hours while returning the temperature to 17 ° C., and further stirred for 14 hours at room temperature. The obtained mixture was analyzed by GC, and the yield was calculated using n-dodecane as an internal standard. As a result, t-pentyltrichlorosilane was 66%.

Example 4 (Production of t-butylmethylchlorosilane)
6.92 (60.2 mmol) of methyldichlorosilane and 0.60 g (6.1 mmol) of copper (I) chloride were mixed with 53.9 g of tetrahydrofuran, and cooled to −40 ° C. using a cooler. To this, 29 mL (64 mmol) of 2.2 M concentration of t-butylmagnesium chloride was added dropwise over 70 minutes. The mixture was stirred for 240 minutes while maintaining the refrigerant temperature, and further stirred for 3 hours while returning the temperature to 14 ° C., and further stirred for 14 hours at room temperature. The obtained mixture was analyzed by GC, and the yield was calculated using n-dodecane as an internal standard. As a result, the yield was 85% of t-butylmethylchlorosilane.

Example 5 (Production of t-butylethyldichlorosilane)
9.75 g (59.6 mmol) of ethyltrichlorosilane and 0.589 g (5.95 mmol) of copper (I) chloride were mixed with 53.5 g of tetrahydrofuran, and cooled to −40 ° C. using a cooler. To this, 29 mL (64 mmol) of 2.2 M concentration of t-butylmagnesium chloride was added dropwise over 70 minutes. The mixture was stirred for 240 minutes while maintaining the refrigerant temperature, and further stirred for 2.5 hours while returning the temperature to 14 ° C., and further stirred for 15 hours at room temperature. The obtained mixture was analyzed by GC, and the yield was calculated using n-dodecane as an internal standard. As a result, the yield was 91% of t-butylethyldichlorosilane.

Comparative Example 1
37.3 g (220 mmol) of tetrachlorosilane and 0.563 g (5.69 mmol) of copper (I) chloride were mixed with 23.5 g of tetrahydrofuran. To this, 5.87 g (242 mmol) of magnesium, 20.3 g (219 mmol) of t-butyl chloride, and t-butylmagnesium chloride prepared from 195 g of tetrahydrofuran were added dropwise at 27 to 35 ° C. over 148 minutes. The mixture was heated under reflux for 3 hours. The obtained mixture was analyzed by ¹ H NMR, and the yield was calculated using tetrahydrofuran as an internal standard. As a result, t-butyltrichlorosilane was 44% and bis (t-butyl) dichlorosilane was 5%.

Comparative Example 2
8.05 g (47.4 mmol) of tetrachlorosilane and 0.312 g (2.56 mmol) of copper (I) thiocyanate were mixed with 42.7 g of tetrahydrofuran. To this, 24 mL (48 mmol) of 2.0 M t-butylmagnesium chloride was added dropwise at 24 to 28 ° C. over 120 minutes. The resulting mixture exhibited a strong sulfur odor. This was analyzed by ¹ H NMR, and the yield was calculated using tetrahydrofuran as an internal standard. As a result, t-butyltrichlorosilane was 78% and bis (t-butyl) dichlorosilane was 13%.

Comparative Example 3
27.4 g (161 mmol) of tetrachlorosilane and 0.472 g (4.76 mmol) of copper (I) chloride were mixed with 152 g of tetrahydrofuran. This was cooled in a cooling bath of an ice bath (0 ° C.), and 80 mL (160 mmol) of 2.0 M t-butylmagnesium chloride was added dropwise over 56 minutes. After the addition was completed, the mixture was stirred at 24 ° C. for 16 hours. The obtained mixture was analyzed by ¹ H NMR, and the yield was calculated using tetrahydrofuran as an internal standard. As a result, it was found that t-butyltrichlorosilane was 71% and bis (t-butyl) dichlorosilane was 13%. The mixture was filtered to remove solids, and the mixture was added dropwise to a mixed solution of 44.5 g (966 mmol) of ethanol and 49.0 g (484 mmol) of triethylamine at 25 to 32 ° C. over 74 minutes. The mixture was heated under reflux for 3 hours. The resulting mixture was filtered to remove solids, and the solvent was distilled off under reduced pressure. The residue was distilled under reduced pressure (92 ° C., 8 kPa) to obtain 15.7 g of a colorless and transparent liquid. According to analysis by GC, this liquid was a mixture containing 70% of t-butyltriethoxysilane, and it was not possible to isolate t-butyltriethoxysilane.

Claims (8)

A method for producing a tertiary alkylsilane, comprising reacting a tertiary alkyl Grignard reagent with chlorosilane at -130 ° C to -20 ° C in the presence of copper (I) chloride .   The method according to claim 1, wherein the chlorosilane is tetrachlorosilane, methyldichlorosilane, or ethyltrichlorosilane.   3. The method according to claim 1, wherein the tertiary alkyl Grignard reagent is t-butylmagnesium halide or t-pentylmagnesium bromide.   The method according to any one of claims 1 to 3, wherein the tertiary alkylsilane is t-butyltrichlorosilane, t-butylmethylchlorosilane, t-butylethyldichlorosilane, or t-pentyltrichlorosilane. The method according to any one of claims 1 to 4 , wherein the reaction is carried out at -80C to -20C. A tertiary alkyl silanes produced by the production method according to any one of claims 1 to 5, is reacted with an alcohol, the production method of the tertiary alkyl alkoxysilane. The method according to claim 6 , wherein the alcohol is an alkyl alcohol having 1 to 3 carbon atoms. The method according to claim 6 or 7 , wherein the alcohol is methanol or ethanol.