JPH03264683A - Production of disilane - Google Patents

Abstract

PURPOSE:To drastically reduce the generation of the corresponding siloxane and to obtain disilane in high yield by subjecting a halosilane to an electrode reaction using Mg, Cu, Zn, Sn or Al as the anode. CONSTITUTION:The halosilane (e.g. dimethylphenylchlorosilane) shown by formula I is subjected to an electrode reaction using Mg, Cu, Zn, Sn or Al as the anode by using a solvent such as THF. As a result, a disilane (e.g. 1,2- diphenyl-1,1,2,2-tetramethyldisilane) shown by formula II is obtained in high yield. Lithium perchlorate, etc., are preferably used as the supporting electrolyte to be used in the electrode reaction. In this case, a halosilane as the raw material, the supporting electrolyte and a solvent are charged into a reaction vessel and mechanically or magnetically agitated, and a specified quantity of the electric current is applied to cause the electrode reaction. The reaction is preferably carried out at -5 to 30 deg.C or more preferably at about 0 to 25 deg.C.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method for producing disilane.

Prior art and its problems Disilane is attracting attention as an intermediate for producing compounds having a 5i-8i bond that are useful as ceramic precursors, optical/electronic materials, and the like.

Conventionally, a known method for producing disilane is to use an alkali metal or alkaline earth metal such as sodium metal, stir the halosilane in a solvent for a long time at a temperature around the boiling point of the solvent, and reductively couple the halosilane. (
J, Organicmet, Chem.

13 (1968) 323-328). However, this method requires harsh reaction conditions (e.g., long-term heating is required) and requires the use of large amounts of alkali metals when produced on an industrial scale, resulting in significant safety concerns. It has drawbacks such as problems.

As a method to overcome these drawbacks, a production method under mild conditions has been proposed in which chlorosilane is electrolytically reduced at room temperature to produce disilane (Angew, Ch.
em, lnt, Ed, Engl,, 15 (197B)
370J, Organicmet, Chem, 21
2 (1981) 1551 o This manufacturing method uses mercury or cadmium for the anode, platinum, mercury, lead, titanium, or iron for the cathode in an H-type cell with a diaphragm, and tetra-perchlorate as the supporting electrolyte. It uses n-butylammonium and 1,2-dimethoxyethane as a solvent. However, in this method, (a) the yield is extremely low, about 10.5% in the case of hexamethyldisilane production and about 13.9% in the case of hexaphenyldisilane production, and (b) the yield of the corresponding siloxane ( For example, when the raw material is trimethylchlorosilane, there is a lot of by-product (hexamethyldisiloxane), and it is difficult to separate the desired disilane and siloxane, making it difficult to obtain highly pure disilane. Since mercury or cadmium is used as the anode, it is difficult to say that it is suitable as an industrial method, as it not only lacks operability and safety, but also poses a risk of environmental pollution. .

Means for Solving the Problems As a result of extensive research in view of the current state of the prior art as described above, the inventor of the present invention has found that, by subjecting halosilane to an electrode reaction using a specific metal as an anode, the present inventors have solved the problem of the prior art. It has been found that the problems are substantially eliminated or significantly reduced.

We have also found that in such electrode reactions, reaction efficiency and yield can be greatly improved by switching the polarity of the picture electrode at regular time intervals.

As a result of further research, the inventors of the present invention found that during the electrode reaction as described above, when the reactor or reaction solution is irradiated with ultrasonic waves, the reaction time can be significantly shortened.

That is, the present invention provides the following method for producing disilane: ■ A method for producing disilane, which has the general formula % (1) (wherein R1, R2 and R3 are the same - or (Differently, each represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, or an amino group, and X represents a halogen atom) By subjecting a halosilane represented by the following to an electrode reaction using Mg, CuZnSSn or i as an anode,
A method characterized by forming a disilane represented by the general formula % (2) (wherein R1, R2 and R3 are the same as above).

■ A method for producing disilane, comprising the general formula % (1) (wherein R1, R2 and R3 are the same or different and each represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group). , X represents a halogen atom) Mg, Cu,
A method characterized by forming a disilane represented by the general formula % (wherein R1, R2 and R3 are the same as above) by subjecting it to an electrode reaction using ZnSSn or AQ as an anode: and A method for producing disilane, comprising the general formula (wherein R1, R
2 and R3 are the same or different, and each represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, or an amino group, and X represents a halogen atom. The general formula R2R2 R1-8i-81-R1(2) 3 can be obtained by using the same or different type of conductive material as one pole and subjecting it to an electrode reaction in which the polarity of the electrode is changed at regular time intervals using the same or different type of conductive material as the other pole. A method characterized by forming a disilane represented by R3 (wherein R1, R2 and R3 are the same as above).

■ A method for producing disilane, comprising the general formula % (1) (wherein R1, R2 and R3 are the same or different and each represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group). , X represents a halogen atom) under ultrasonic irradiation.
By subjecting Zn, Sn or AQ to one pole and the same or different type of conductive material as the other pole to an electrode reaction in which the polarity of the electrode is switched at regular time intervals, the general formula % formula % (2) can be obtained. A method characterized by forming a disilane represented by the formula (wherein R□, R2 and R3 are the same as above).

In the following, each of the above-mentioned inventions
These are referred to as the invention to the fourth invention of the present application, and these are collectively referred to simply as the present invention.

In the present invention, the halosilane used as a starting material has the general formula % (1) (where R1, R2, and R3 are the same or different, and each represents a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group. or represents an amino group, and X represents a halogen atom).

In addition, the reaction product in the present invention has the general formula % formula % (2
) (wherein R1, R2 and R3 are the same as above).

In general formula (1), the hydrogen atoms, amino groups, and organic substituents represented by R1, R2, and R3 may be different from each other, or two or more of them may be the same. Examples of the alkyl group include those having about 1 to 10 carbon atoms, and among these, those having 1 to 6 carbon atoms are more preferable.

Examples of the aryl group include a phenyl group, a phenyl group having at least one alkyl group having 1 to 6 carbon atoms as a substituent, and a p-alkoxyphenyl group. Examples of the alkoxy group include those having about 1 to 10 carbon atoms, and among these, those having 1 to 6 carbon atoms are more preferable. When R, R2 and R3 are the above amino group and organic substituent, the hydrogen atom is another alkyl group,
It may be substituted with a functional group such as an aryl group or an alkoxy group.

Furthermore, in general formula (1), X is a halogen atom (C
LF, Br, I). As the halogen atom, CΩ is more preferable.

In the method of the present invention, one type of halosilane represented by general formula (1) may be used alone, or two types may be used in combination. It is preferable that the halosilane has as high a purity as possible. For example, for liquid halosilane, it is preferable to use it by drying it with calcium hydride and distilling it, and for solid halosilane, it is preferable to use it by recrystallization method. It is preferable to purify and use it.

During the reaction, halosilane is used after being dissolved in a solvent. As a solvent, aprotic solvents can be widely used.
More specifically, propylene carbonate, acetonitrile, dimethylformamide, dimethyl sulfoxide,
Examples include ether solvents such as 1,2-dimethoxyethane, bis(2-methoxyethyl)ether, p-dioxane, tetrahydrofuran, and 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 halosilane in the solvent is too low, the current efficiency decreases, whereas if it is too high, the supporting electrolyte may not dissolve. Therefore, the concentration of halosilane in the solvent is usually about 0.05 to 6 mol/Q, more preferably about 0.1 to 3 [1 Iol/Q, particularly preferably 0. 2-0. It is about 8 mol/Q.

Supporting electrolytes used in the present invention include alkali metal perchlorates such as sodium perchlorate and lithium perchlorate;
Alkali metal tetrafluoroborates, such as lithium tetrafluoroborate; Tetraalkylammonium halides, such as tetra-n-butylammonium chloride; Tetraalkylammonium perchlorates, such as tetra-n-butylammonium perchlorate; Tetra-n-tetrafluoroborates −
Examples include tetraalkylammonium tetrafluoroborate such as butylammonium.

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 preferred, and lithium perchlorate and tetra-n-butylammonium perchlorate are more preferred. is most preferred. If the supporting electrolyte concentration is too low,
If the ionic conductivity given to the reaction solution is low, the reaction will not proceed sufficiently, whereas if it is too high, too much current will flow, making it impossible to obtain the potential necessary for the reaction. Therefore, the concentration of supporting electrolyte in the solvent is usually 0.05~
5IIIoI/Q, more preferably 0.1 to
It is about 3 mol/R, particularly preferably 0. 15~
1. It is about 2 mol/Q.

In the first invention of the present application, Mg is used as the anode.

Any one of CuSZn, Sn, and AQ, or an alloy containing these metals as a main component is used. The cathode is not particularly limited as long as it is a material that can conduct electric current, but Mg5
CuSZn, 5nSAQ.

It is preferable to use either Ni or co or an alloy containing these metals as main components. As an anode,
Mg5Cu and alloys containing these metals as main components are more preferred, and Mg is most preferred. The shape of the electrode is not particularly limited as long as it can conduct electricity stably, but it may be rod-shaped,
Preferably, the material is plate-shaped, cylindrical, or a plate-shaped body wound into a coil. It is preferable to remove as much of the oxide film as possible from the surface of the electrode in advance. The oxide film from the electrode may be removed by any method; for example, the electrode may be washed with acid, then washed with ethanol and ether, and then dried under reduced pressure, or the electrode may be polished in a nitrogen atmosphere. This can be done by a method or a combination of these methods.

When carrying out the first invention of the present application, a halosilane represented by the general formula (1) and a supporting electrolyte are housed together with a solvent in a sealable reaction vessel equipped with an anode and a cathode,
The electrode reaction is preferably carried out by applying a predetermined amount of current while stirring mechanically or magnetically. The inside of the reaction vessel may be in a dry atmosphere, but it is more preferably a dry nitrogen or inert gas atmosphere, and most preferably a deoxidized and dry nitrogen or inert gas atmosphere. The amount of current to be applied is usually about 1 to 5F1 mole, more preferably about 1.1 to 3F1 mole, and most preferably about 1.1 to 3F1 mole, based on halosilane.
It is about 3 to 2.3F per mole. The reaction time varies depending on the amount of raw material halosilane, the amount of supporting electrolyte, the resistance of the electrolyte, etc., but is usually about 0.5 to 100 hours, for example, when the concentration of raw material halosilane is 0.4 mol/Q. About 10-250-25 hours. The temperature during the reaction is usually -
The temperature range is from 10°C to below the boiling point of the solvent used, more preferably about -5 to 30°C, and most preferably about 0 to 25°C. A diaphragm, which is required in normal electrode reduction reactions, may or may not be used.

The second invention of the present application is not substantially different from the first invention of the present application except that ultrasonic waves are irradiated to the reaction container or reaction solution during electrode reaction. The ultrasonic irradiation method during the electrode reaction is not particularly limited, but includes a method of placing the reactor in an ultrasonic bath and irradiating it, and a method of placing an ultrasonic oscillator in the reactor and irradiating it. Examples include. The frequency of the ultrasonic waves is preferably about 10 to 70 kHz. The output of the ultrasonic wave can be adjusted appropriately depending on the reaction conditions such as the type of raw materials, the amount of reaction solution, the shape and size of the reaction container and electrodes, the material and surface area of the electrodes, but it is usually per 1Q of reaction solution. It is within the range of about 0.01 to 24 kW. By such ultrasonic irradiation, the reaction time can be greatly shortened, and for example, the concentration of the raw material halosilane can be reduced to 0.4.
When it is mol/Q, it is about 5 to 12 hours. In the second invention of the present application, stirring is performed well by ultrasonic irradiation, but if necessary, stirring by mechanical means may be used in combination.

In the third invention of the present application, MgXCu, Zn.

Except for switching the polarity of the electrode at fixed time intervals with Sn or AQ as one pole and the same or different type of conductive material (Ni, Co, etc.) as the other pole.
The reaction is carried out in the same manner as in the first invention of the present application. By switching the polarity, the current value is stabilized and the reaction proceeds smoothly, and the reaction time is shortened compared to the first invention of the present application, typically about 5 to 10 hours. The polarity switching is normally 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. When switching the polarity, it is most preferable to configure the two electrodes with the same type of metal because the metal ions move between the two electrodes, which reduces wear on the electrodes and increases the yield of disilane. .

In the third invention of the present application in which the polarity of the picture electrode is switched, it is preferable that no diaphragm is used.

In the fourth invention of the present application, ultrasonic waves are irradiated to the reaction container or reaction solution during electrode reaction. The fourth invention of the present application is not substantially different from the third invention of the present application except for the irradiation of ultrasonic waves. Moreover, the ultrasonic irradiation may be performed in the same manner as in the case of the second invention of the present application. In the fourth invention of the present application, by combining polarity switching and ultrasonic irradiation, the reaction time is further shortened to a large extent, and the color typically lasts for 2 to 6 hours. Also in the fourth invention of the present application, if necessary, stirring by mechanical means may be used in combination.

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

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

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

(b) Since mercury or cadmium is not used, operability and safety are excellent, and the risk of environmental pollution can be avoided.

(C) Operation is simple because no diaphragm is required.

(d) When ultrasonic waves are irradiated during the electrode reaction, the reaction time can be significantly reduced to about half or less.

(e) The method of the present invention applies not only to disilane but also to other 5i-
It can also be applied to the production of compounds having an 8i bond.

EXAMPLES Examples will be shown below to further clarify the features of the present invention.

Example 1 Three-way cock and Mg electrode (1 cm x 1 cm x 5
0.64 cm) of anhydrous lithium perchlorate into a third flask (hereinafter referred to as the reactor) with an internal volume of 30 m1 equipped with two flasks.
After heating and reducing the pressure to 50°C and lmmHg to dry the lithium perchlorate, deoxygenated dry nitrogen was introduced into the reactor, and 15ml of tetrahydrofuran previously dried with sodium-benzophenone ketyl was added. added. Add to this 1 ml (6 mmol) of dimethylphenylchlorosilane, which was previously dried with calcium hydride and distilled.
was added using a syringe, and while the reactor was maintained at room temperature using a water bath, electricity was applied using a constant voltage power supply. At this time, electricity was applied for about 9 hours using a commutator to change the polarity of the two electrodes every minute so that the amount of electricity applied was 2F/mol based on dimethylphenylchlorosilane 3.

After the reaction was completed, the reaction solution was adsorbed on silica gel, and tetrahydrofuran was sufficiently suctioned off using a water jet pump.The silica gel with the reaction solution adsorbed on the developer was placed in a silica gel column, and the product was isolated using hexane solvent. .

Analysis of the product revealed that it was 1,2-diphenyl-1,1
, 2,2-tetramethyldisilane was obtained in a yield of 92.3%, and it was confirmed that 5iSi bonds were generated in a high yield.

Note that the proportion of siloxane produced as a by-product 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 with 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 current is 2F/mo! It only took about 4 hours to complete.

Analysis of the product revealed 1,2-diphenyl 1.1.
2.2-Tetramethyldisilane was obtained with a yield of 91.7%, and it was confirmed that 5i-8i bonds were produced in 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 the raw material represented by 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 the recrystallization method was used as the raw material represented by the general formula (1). Then, 100 ml of IN hydrochloric acid was added and after filtration, the obtained solid product was washed with IN hydrochloric acid and ethanol.

As a result of the analysis, it was confirmed that hexaphenyldisilane was obtained in a yield of 85.3%, and that a 5i-8i bond was produced in a high yield.

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

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

Example 6 M g (l cmX l cmX 5cm
) was used as the cathode, and Ni (1cmXO, 1cm
Dimethylphenylchlorosilane was subjected to an electrode reaction in the same manner as in Example 1, except that the electrode polarity was not changed. It took about 21 hours until the amount of current applied reached 2F/+1101.

As a result, 1,2-diphenyl-1 was obtained with a yield of 90.7%.
, 1,2,2-tetramethyldisilane is obtained,
It was confirmed that 5i-8i bonds were produced in high yield.

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

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

Example 8 An electrode reaction of dimethylphenylchlorosilane was carried out in the same manner as in Example 1 except that the time interval for polarity conversion was 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 the supporting electrolyte.

As a result of analysis, 1,2-diphenyl-
It was confirmed that 1,1,2,2-tetramethyldisilane was obtained and that 5i-8i bonds were produced in high yield.

Example 10 Dimethylphenyl was prepared in the same manner as in Example 1 except that tetra-n-butylammonium perchlorate was used as the supporting electrolyte and 15 ml of 1°2-dimethoxyethane previously dried with sodium-benzophenone ketyl was used as the solvent. An electrode reaction of chlorosilane was carried out.

As a result of the analysis, 1,2-Schif8 Uniru 1.1,2,2-tetramethyldisilane was obtained in a yield of 49.6%, indicating that a 5i-8i bond was formed in a good yield. This was confirmed.

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

As a result, 1,2-dibenzyl-1 was obtained with a yield of 78.0%.
, 1,2,2-tetramethyldisilane is obtained,
It was confirmed that 5i-8i bonds were produced in high yield.

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

As a result, 1,2-diphenyl-1 was obtained with a yield of 21.2%.
, 2-dimethyldisilane was obtained, and it was confirmed that 5i-3i bonds were produced in good yield.

Example 13 Electrode reaction was carried out in the same manner as in Example 1 except that allyldimethylchlorosilane was used as the raw material represented by 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 AQ (1 cm x O, 1 cm x 5 cm) was used as the picture electrode.

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

Example 15 Trimethylchlorosilane (3 mmol) and triphenylchlorosilane (3 mmol) were used as raw materials represented by general formula (1).
The electrode reaction was carried out in the same manner as in Example 1, except that 2 mmol) was used.

After the reaction was completed, it was confirmed by gas chromatography that hexamethyldisilane was not produced, and 100 ml of IN hydrochloric acid was added, followed by extraction with ether. Analysis of the white solid obtained by the extraction revealed that hexaphenyldisilane was produced at a yield of 61.1%.

In addition, as a result of analyzing the solid obtained by distilling off the ether from the ether layer, it was found that
It was found that 24-lymethyldisilane was obtained in a yield of 30.3%.

Example 16 Electrode reaction was carried out in the same manner as in Example 6, except that the reactor was immersed in an ultrasonic cleaner with an output of 60 W and a frequency of 45 kHz. The time it takes for the amount of current to reach 2F/mol is approximately 1
It was 0 hours.

Analysis of the product revealed that 1,2-diphenyl-1-1.1,2.2-tetramethyldisilane was 91.3
It was confirmed that the 5i-8i bond was produced in a high yield.

(that's all) 2

Claims (1)

[Claims] [1] A method for producing disilane, which has the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (1) (In the formula, R_1, R_2 and R_3 are the same or different, and each represents a hydrogen atom. , an alkyl group, an aryl group, an alkoxy group, or an amino group, and X represents a halogen atom) is subjected to an electrode reaction using Mg, Cu, Zn, Sn, or Al as an anode. A method characterized by forming a disilane represented by the formula ▲ Numerical formula, chemical formula, table, etc. ▼ (2) (in the formula, R_1, R_2 and R_3 are the same as above). [2] A method for producing disilane, which includes the general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (1) (In the formula, R_1, R_2, and R_3 are each the same or different, and each represents a hydrogen atom, an alkyl group, or an aryl group. , represents an alkoxy group or an amino group, and X represents a halogen atom).
By subjecting to an electrode reaction using Zn, Sn or Al as an anode, disilane represented by the general formula ▲Mathematical formula, chemical formula, table, etc.▼(2) (wherein R_1, R_2 and R_3 are the same as above) A method characterized by forming. [3] A method for producing disilane, which includes the general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (1) (In the formula, R_1, R_2 and R_3 are the same or different, and each represents a hydrogen atom, an alkyl group, an aryl group. , represents an alkoxy group or an amino group, and X represents a halogen atom) with Mg, Cu, Zn, Sn, or Al as one pole, and a conductive material of the same or different type as these as the other pole. By subjecting it to an electrode reaction in which the polarity of the electrode is changed at regular time intervals, the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (2) (in the formula, R_1, R_2 and R_3 are the same as above). A method characterized by forming disilane. [4] A method for producing disilane, which includes the general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (1) (In the formula, R_1, R_2 and R_3 are the same or different, and each represents a hydrogen atom, an alkyl group, an aryl group. , represents an alkoxy group or an amino group, and X represents a halogen atom).
By subjecting Zn, Sn or Al to one pole and a conductive material of the same or different type as the other pole, the general formula ▲mathematical formula, chemical formula, table ▼(2) A method characterized by forming a disilane represented by the formula (wherein R_1, R_2 and R_3 are the same as above).