JP3016087B2 - Method for producing disilane - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing disilane.

2. Description of the Related Art Disilane has attracted attention as an intermediate in the production of compounds having a Si-Si bond, which are useful as ceramic precursors, optical and electronic materials, and the like.

Conventionally, as a method for producing disilane, using an alkali metal or alkaline earth metal such as metal sodium,
A method is known in which a halosilane in a solvent is stirred for a long time at a temperature about the boiling point of the solvent and reductively coupled {J. Organization. Chem., 13 (1968) 323-328}. However, this method requires severe reaction conditions (for example, long-time heating is required), and in the case of production on an industrial scale, a large amount of alkali metal is used. It has drawbacks such as problems.

As a method for overcoming such drawbacks, a production method under mild conditions of producing chlorosilane by electrode reduction at room temperature to produce disilane has been proposed (Angew.Chem.In.
t.Ed.Engl., 15 (1976) 370, J.Organicmet.Chem., 212 (1
981) 155｝. This production method uses mercury or cadmium for the anode, platinum, mercury, lead, titanium or iron for the cathode and tetra-n-butylammonium perchlorate as the supporting electrolyte in an H-type cell with a diaphragm. And using 1,2-dimethoxyethane as a solvent. However, according to this method, (a) the yield is extremely low, about 10.5% in the case of producing hexamethyldisilane, and about 13.9% in the case of producing hexaphenyldisilane. In the case of chlorosilanes, hexamethyldisiloxane) is often produced as a by-product, and it is difficult to separate the target disilane and siloxane. Therefore, it is difficult to obtain high-purity disilane.
(C) Since mercury or cadmium is used as the anode, not only lacks operational operability and safety,
It is hard to say that it is suitable as an industrial method in that there is a risk of environmental pollution.

Means for Solving the Problems The present inventor has conducted intensive studies in view of the state of the prior art as described above, and as a result, by subjecting halosilane to an electrode reaction using a specific metal as an anode, It has been found that the problem is substantially eliminated or greatly reduced.

It has also been found that in such an electrode reaction, by switching the polarities of both electrodes at fixed time intervals, the reaction efficiency and the yield are greatly improved.

As a result of further studies, the present inventor has found that, in the above-described electrode reaction, when the reactor or the reaction solution is irradiated with ultrasonic waves, the reaction time is greatly reduced.

That is, the present invention provides the following method for producing disilane: A method for producing disilane, which comprises a general formula Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom. By subjecting to an electrode reaction using Cu, Zn, Sn or Al as the anode, the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as described above).

A method for producing disilane, comprising the general formula (Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom). Mg, Cu, Zn,
By subjecting it to an electrode reaction using Sn or Al as the anode, the general formula Wherein R ₁ , R ₂ and R ₃ are the same as defined above, and a method for producing disilane, Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom. , Cu, Zn, Sn or Al as one of the electrodes, and using the same or different conductive material as the other electrode and subjecting it to an electrode reaction that switches the polarity of the electrode at certain time intervals. (Wherein R ₁ , R ₂ and R ₃ are the same as described above).

A method for producing disilane, comprising the general formula (Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom). Mg, Cu, Zn,
By using Sn or Al as one of the electrodes and using the same or different conductive material as the other electrode for an electrode reaction that switches the polarity of the electrodes at regular time intervals, the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as described above).

Hereinafter, the above-described inventions will be referred to as first to fourth inventions of the present application, respectively, and these will be collectively referred to simply as the present invention.

In the present invention, the halosilane used as a starting material has a general formula (Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom). .

The reaction product in the present invention has a general formula (Wherein R ₁ , R ₂ and R ₃ are the same as above).

In the general formula (1), the hydrogen atom, amino group and organic substituent represented by R ₁ , R ₂ and R ₃ may be different from each other, or two or more may be the same. Examples of the alkyl group include those having about 1 to 10 carbon atoms, and among them, those having 1 to 6 carbon atoms are more preferable. As the aryl group, a phenyl group, a carbon number of 1 to 6
And a p-alkoxyphenyl group having at least one alkyl group as a substituent. Examples of the alkoxy group include those having about 1 to 10 carbon atoms, and among them, those having 1 to 6 carbon atoms are more preferable. When R ₁ , R ₂ and R ₃ are the amino group and the organic substituent described above, the hydrogen atom is another alkyl group,
It may be substituted by a functional group such as an aryl group or an alkoxy group.

In the general formula (1), X represents a halogen atom (Cl, F, Br, I). Cl is more preferred as the halogen atom.

In the method of the present invention, one type of halosilane represented by the general formula (1) may be used alone, or two types may be used in combination. The halosilane is preferably as pure as possible.For example, liquid halosilane is preferably dried with calcium hydride and used by distillation, and solid halosilane is preferably recrystallized by a recrystallization method. Purification and use are preferred.

At the time of the reaction, the halosilane is used after being dissolved in a solvent. As the solvent, an aprotic solvent can be widely used, and more specifically, propylene carbonate, acetonitrile, dimethylformamide, dimethyl sulfoxide, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, p-dioxane , Tetrahydrofuran,
Examples thereof include ether solvents such as methylene chloride. These solvents can be used alone or as a mixture of two or more. As the solvent, 1,2-dimethoxyethane and tetrahydrofuran are more preferred. If the concentration of the halosilane in the solvent is too low, the current efficiency decreases, while if it is too high, the supporting electrolyte may not be dissolved. Therefore, the concentration of the halosilane in the solvent is usually about 0.05 to 6 mol /, more preferably about 0.1 to 3 mol /, and particularly preferably 0.2 to 0.8.
mol / degree.

The supporting electrolyte used in the present invention includes: alkali metal perchlorates such as sodium perchlorate and lithium perchlorate; alkali metal tetrafluoroborate such as lithium tetrafluoroborate; halogenation such as tetra-n-butylammonium chloride Tetraalkylammonium; tetraalkylammonium perchlorate such as tetra-n-butylammonium perchlorate; and tetraalkylammonium tetrafluoroborate such as tetra-n-butylammonium tetrafluoroborate. These supporting electrolytes may be used alone or in combination of two or more. Among these supporting electrolytes, lithium perchlorate, tetra-n-butylammonium perchlorate and tetra-n-butylammonium tetrafluoroborate are more preferable, and lithium perchlorate and tetra-n-butylammonium perchlorate are more preferable. Is most preferred. If the concentration of the supporting electrolyte is too low, the reaction does not proceed sufficiently due to the low ionic conductivity given to the reaction solution, whereas if it is too high, the current flows too much and the reaction is necessary for the reaction. High potential cannot be obtained. Therefore, the concentration of the supporting electrolyte in the solvent is usually 0.05 to 5 mol /
Degree, more preferably 0.1 to 3 mol / about,
Particularly preferably, it is about 0.15 to 1.2 mol /.

In the first invention of the present application, Mg, Cu, Zn,
Either Sn or Al or an alloy mainly containing these metals is used. The cathode is not particularly limited as long as it is a substance that can pass an electric current, but may be Mg, Cu, Zn, Sn, Al, Ni
It is preferable to use any one of Co and Co or an alloy mainly containing these metals. Mg, Cu as anode
And alloys containing these metals as main components are more preferable, and Mg is most preferable. The shape of the electrode is not particularly limited as long as the current can be supplied stably, but is preferably a rod-like, plate-like, tubular-like, or a plate-like body wound in a coil shape. It is preferable to remove the oxide film from the surface of the electrode as much as possible in advance. The removal of the oxide film from the electrode may be performed by any method.For example, after the electrode is washed with an acid, washed with ethanol and ether, and dried under reduced pressure, and the electrode is polished under a nitrogen atmosphere. It can be carried out by a method or a method combining these methods.

In practicing the first invention of the present application, the halosilane represented by the general formula (1) and the supporting electrolyte are accommodated together with a solvent in a sealable reaction vessel provided with an anode and a cathode, and preferably stirred mechanically or magnetically. At the same time, an electrode reaction is performed by applying a predetermined amount of current. The inside of the reaction vessel may be a dry atmosphere, but more preferably a dry nitrogen or inert gas atmosphere, and most preferably a deoxygenated and dry nitrogen or inert gas atmosphere. The amount of electricity is usually about 1 to 5 F / mol, more preferably about 1.1 to 3 F / mol, and most preferably 1.3 to
It is about 2.3 F / mol. The reaction time varies depending on the amount of the raw material halosilane, the resistance of the electrolytic solution related to the amount of the supporting electrolyte, and the like, but is usually about 0.5 to 100 hours. It is. The temperature during the reaction is usually within a temperature range from -10 ° C to the boiling point of the solvent used or lower, and more preferably-
The temperature is about 5 to 30C, most preferably about 0 to 25C. The diaphragm required in a normal electrode reduction reaction may or may not be used.

The second invention of the present application is substantially the same as the first invention of the present application except that the reaction vessel or the reaction solution during the electrode reaction is irradiated with ultrasonic waves. The method of irradiating the ultrasonic wave during the electrode reaction is not particularly limited, but a method of irradiating the reactor with the ultrasonic bath contained therein, and a method of irradiating the reactor with an ultrasonic oscillator inserted therein. And the like. The frequency of the ultrasonic wave is preferably set to about 10 to 70 kHz. The output of the ultrasonic wave may be appropriately determined according to the reaction conditions such as the type of the raw material, the amount of the reaction solution, the shape and size of the reaction vessel and the electrode, the material and the surface area of the electrode. It is in the range of ~ 24kW. The reaction time is greatly shortened by such ultrasonic irradiation,
For example, when the concentration of the raw material halosilane is 0.4 mol /, it takes about 5 to 12 hours. In the second invention of the present application, stirring is preferably performed by ultrasonic irradiation, but if necessary, stirring by mechanical means may be used in combination.

In the third invention of the present application, Mg, Cu, Zn, Sn, or Al is used as one electrode, and the same or different conductive material (Ni, Co, etc.) is used as the other electrode, and the polarity of the electrode is set at a constant time interval. The reaction is carried out by the same operation as in the first invention of the present application, except for switching. By this polarity switching, the current value is stabilized and the reaction proceeds smoothly, and the reaction time is shorter than that of the first invention of the present application, typically about 5 to 10 hours. The polarity switching is usually performed at intervals of about 0.01 seconds to 60 minutes, more preferably at intervals of about 1 second to 10 minutes, and particularly preferably at intervals of about 10 seconds to 3 minutes.
In the case of performing polarity switching, it is most preferable that the two electrodes are formed of the same kind of metal, since the metal ions move between the two electrodes, so that the consumption of the electrodes is small and the yield of disilane is high. . In the third invention of the present application in which the polarities of both electrodes are switched, it is preferable not to use a diaphragm.

In the fourth invention of the present application, ultrasonic waves are applied to the reaction vessel or the reaction solution during the electrode reaction. The fourth invention of the present application is substantially the same as the third invention of the present invention except that the ultrasonic wave is applied. Irradiation of ultrasonic waves may be performed in the same manner as in the case of the second invention of the present application. Application No. 4
In the present invention, the combined use of the switching of the polarity and the ultrasonic irradiation further shortens the reaction time further, typically to about 2 to 6 hours. In the fourth invention of the present application,
If necessary, stirring by mechanical means may be additionally used.

In the present invention, in order to suppress the by-product of siloxane, it is desirable to remove the water in the solvent and the supporting electrolyte in advance. For example, when tetrahydrofuran or 1,2-dimethoxyethane is used as the solvent, it is preferable that drying with sodium-benzophenone ketyl or the like be performed in advance. In the case of a supporting electrolyte, it is preferable to dry by heating under reduced pressure or to remove water by adding a substance (for example, trimethylchlorosilane) which reacts easily with water and can be easily removed.

Effects of the Invention According to the present invention, the following remarkable effects are achieved.

(A) The production of the corresponding siloxane can be greatly suppressed, and the yield of disilane can be increased.

(B) Since no mercury or cadmium is used, operability and safety are excellent, and the risk of environmental pollution can be avoided.

(C) Since the use of a diaphragm is not required, the operation is simple.

(D) When ultrasonic irradiation is performed during the electrode reaction, the reaction time can be significantly reduced to about half or less.

(E) The method of the present invention is applicable not only to disilane but also to other Si-Si
It can be applied to the production of a compound having a bond.

Examples Examples are given below to further clarify features of the present invention.

Example 1 A three-necked flask (hereinafter referred to as a reactor) having a capacity of 30 ml equipped with a three-way cock and two Mg electrodes (1 cm x 1 cm x 5 cm) was charged with 0.64 g of anhydrous lithium perchlorate at 50C, 1mm
After heating and reducing the pressure to Hg to dry the lithium perchlorate, deoxygenated dry nitrogen was introduced into the reactor, and 15 ml of tetrahydrofuran previously dried with sodium-benzophenone ketyl was added. 1 ml of dimethylphenylchlorosilane dried and distilled in advance with calcium hydride
(6 mmol) was added with a syringe, and while the reactor was kept at room temperature by a water bath, electricity was supplied from a constant voltage power supply.
At this time, while the polarities of the two electrodes were changed every minute using a commutator, electricity was supplied for about 9 hours so that the amount of electricity was 2 F / mol based on dimethylphenylchlorosilane.

After completion of the reaction, the reaction solution was adsorbed on silica gel, and sufficiently removed by suction with a tetrahydrofuran water-jet pump.
Silica gel with the reaction solution adsorbed on a developing agent was put in a silica gel column, and the product was isolated with a hexane solvent.

Analysis of the product revealed that 1,2-diphenyl-1,1,2,2
-Tetramethyldisilane was obtained in a yield of 92.3%, and it was confirmed that Si-Si bonds were generated in high yield.

The ratio of siloxane by-produced was 2% or less.

Example 2 An electrode reaction was carried out in the same manner as in Example 1 except that the reactor was immersed in an ultrasonic cleaner having a frequency of 45 kHz and an output of 60 W, and the reaction solution was continuously irradiated with ultrasonic waves. In this case, the amount of electricity is 2F / m
It only took about 4 hours to reach ol.

Analysis of the product revealed that 1,2-diphenyl-1,1,2,2
-Tetramethyldisilane was obtained at a yield of 91.7%, and it was confirmed that Si-Si bonds were generated at a high yield.

Example 3 An electrode reaction was carried out in the same manner as in Example 1 except that n-octyldimethylchlorosilane was used as a raw material represented by the general formula (1). As a result, it was confirmed that 1,2-di-n-octyl-1,1,2,2-tetramethyldisilane was produced in high yield.

Example 4 An electrode reaction was carried out in the same manner as in Example 1 except that triphenylchlorosilane purified by a recrystallization method was used as a raw material represented by the general formula (1). Next, 100 ml of 1N hydrochloric acid was added, and after filtration, the obtained solid product was 1N
Washed with hydrochloric acid and ethanol.

As a result of the analysis, hexaphenyldisilane was obtained at a yield of 85.3%, and it was confirmed that Si-Si bonds were generated at a high yield.

Example 5 An electrode reaction was carried out in the same manner as in Example 1, except that methyldimethoxychlorosilane purified by a distillation method was used as a raw material represented by the general formula (1).

As a result, it was confirmed that 1,2-dimethyl-1,1,2,2-tetramethoxydisilane was produced in high yield.

Example 6 Dimethyl was prepared in the same manner as in Example 1 except that Mg (1 cm × 1 cm × 5 cm) was used as the anode, Ni (1 cm × 0.1 cm × 5 cm) was used as the cathode, and the polarity of the electrode was not changed. Phenylchlorosilane was subjected to an electrode reaction. The amount of electricity is 2F / mol
It took about 21 hours to reach.

As a result, 1,2-diphenyl-1,1,2,2 with a yield of 90.7%
-Tetramethyldisilane has been obtained, and Si-
It was confirmed that Si bonds were formed.

Example 7 Dimethylphenylchlorosilane was subjected to an electrode reaction in the same manner as in Example 1 except that copper (1 cm × 0.1 cm × 5 cm) was used as two electrodes.

As a result of the analysis, it was confirmed that 1,2-diphenyl-1,1,2,2-tetramethyldisilane was obtained.

Example 8 An electrode reaction was performed with dimethylphenylchlorosilane in the same manner as in Example 1 except that the time interval of the polarity conversion was set to 15 seconds.

As a result of the analysis, it was confirmed that 1,2-diphenyl-1,1,2,2-tetramethyldisilane was obtained in high yield.

Example 9 An electrode reaction of dimethylphenylchlorosilane was carried out in the same manner as in Example 1 except that tetra-n-butylammonium perchlorate was used as a supporting electrolyte.

As a result of analysis, 1,2-diphenyl-1,1,1 was obtained in a yield of 75.2%.
2,2-Tetramethyldisilane has been obtained, and S
It was confirmed that an i-Si bond was generated.

Example 10 1,2-Dimethoxyethane 1 using tetra-n-butylammonium perchlorate as supporting electrolyte and previously dried with sodium-benzophenone ketyl as solvent
The electrode reaction of dimethylphenylchlorosilane was carried out in the same manner as in Example 1 except that 5 ml was used.

As a result of analysis, 1,2-diphenyl-1,1,1 was obtained in a yield of 49.6%.
As a result, 2,2-tetramethyldisilane was obtained, and it was confirmed that Si-Si bonds were formed at a good yield.

Example 11 An electrode reaction was performed in the same manner as in Example 1 except that benzyldimethylmethylchlorosilane was used as a raw material represented by the general formula (1).

As a result, 1,2-dibenzyl-1,1,2,2 with a yield of 78.0%
-Tetramethyldisilane has been obtained, and Si-
It was confirmed that Si bonds were formed.

Example 12 An electrode reaction was carried out in the same manner as in Example 1 except that phenylmethylchlorosilane was used as a raw material represented by the general formula (1).

As a result, 1,2-diphenyl-1,2-dimethyldisilane was obtained at a yield of 21.2%, and it was confirmed that Si-Si bonds were generated at a good yield.

Example 13 An electrode reaction was carried out in the same manner as in Example 1 except that allyldimethylchlorosilane was used as a raw material represented by the general formula (1).

As a result of the analysis, it was confirmed that 1,2-diallyl-1,1,2,2-tetramethyldisilane was obtained.

Example 14 Dimethylphenylchlorosilane was subjected to an electrode reaction in the same manner as in Example 1 except that Al (1 cm × 0.1 cm × 5 cm) was used as both electrodes.

As a result of the analysis, it was confirmed that 1,2-diphenyl-1,1,2,2-tetramethyldisilane was obtained.

Example 15 As raw materials represented by the general formula (1), trimethylchlorosilane (3 mmol) and triphenylchlorosilane (3 mmo) were used.
An electrode reaction was carried out in the same manner as in Example 1 except that l) was used.

After completion of the reaction, confirm that hexamethyldisilane was not generated by gas chromatography.
100 ml was added and extracted with ether. As a result of analyzing the white solid obtained by the extraction, hexaphenyldisilane was found to be 6%.
It was found that the product was produced in a yield of 1.1%.

Analysis of the solid obtained by distilling ether from the ether layer showed that 1,1,1-triphenyl-2,2,2-trimethyldisilane was obtained in a yield of 30.3%. found.

Example 16 An electrode reaction was carried out in the same manner as in Example 6, except that the reactor was immersed in an ultrasonic cleaner having an output of 60 W and a frequency of 45 kHz.
The time required for the amount of electricity to reach 2 F / mol was about 10 hours.

Analysis of the product revealed that 1,2-diphenyl-1,1,2,2
-Tetramethyldisilane was obtained at a yield of 91.3%, and it was confirmed that Si-Si bonds were generated at a high yield.

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Ryoichi Nishida Osaka Gas Co., Ltd. 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka (56) References JP-A-60-59091 (JP, A) JP-A-2-6486 (JP, A) JP-A-3-150382 (JP, A) JP-A-1-226888 (JP, A) JP-A-1-203396 (JP, A) Int.Cl. ⁷ , DB name) C25B 1/00-15/08 C07F 7/08

Claims (4)

(57) [Claims] 1. A method for producing disilane, comprising the steps of: Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom. By subjecting to an electrode reaction using Cu, Zn, Sn or Al as the anode, the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as described above). 2. A method for producing disilane, comprising the steps of: (Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom). Mg, Cu, Zn,
By subjecting it to an electrode reaction using Sn or Al as the anode, the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as described above). 3. A method for producing disilane, comprising the steps of: Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom. , Cu, Zn, Sn or Al as one of the electrodes, and using the same or different conductive material as the other electrode and subjecting it to an electrode reaction that switches the polarity of the electrode at certain time intervals. (Wherein R ₁ , R ₂ and R ₃ are the same as described above). 4. A process for producing disilane, comprising the steps of: (Wherein R ₁ , R ₂ and R ₃ are the same or different and each represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group, and X represents a halogen atom). Mg, Cu, Zn,
By using Sn or Al as one of the electrodes and using the same or different conductive material as the other electrode for an electrode reaction that switches the polarity of the electrodes at regular time intervals, the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as described above).