JPH06256525A - Production of polysilane having phenolic group - Google Patents

Abstract

PURPOSE:To obtain a polysilane having excellent safety, environmental pollution resistance, solubility and film-forming property and useful for resist material, etc., in high efficiency and yield by the electrode reaction of a specific dihalosilane having phenol group using a specific metal as an anode. CONSTITUTION:This polysilane expressed by formula II ((n) is 10-10,000) is produced by the electrode reaction of a dihalosilane of formula I (R<1> is alkoxyalkyl, trialkylsilyl or benzyl; R<2> is H, aryl, alkoxy or amino; X is halogen; (m) is 0-10) using a metal such as Mg as an anode.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polysilane having a phenol group.

[0002]

2. Description of the Related Art Polysilane having a phenol group is expected to be useful as a photoresist material because it is soluble in an alkaline aqueous solution.

Conventionally, as a method for producing a polysilane having a phenol group, dichlorosilanes having a phenol group protected by a silyl group are stirred in an toluene solvent at a temperature of 100 ° C. or higher for a long time using an alkali metal such as sodium metal. Then, after the reductive coupling, the protecting group is treated with an acid,
A method of removing it using an alkali or alcohol is known (see, for example, Macromolecules 1989, 22 , 2933). However, this method requires harsh reaction conditions (eg, long heating times are required),
The molecular weight cannot be controlled at all, and in production on an industrial scale, a large amount of alkali metal is used, which poses a serious safety problem, and the yield is low at around 5%. ing.

[0004]

SUMMARY OF THE INVENTION Therefore, the main object of the present invention is to provide a method for producing a polysilane having a phenol group, which is safe and has a good yield under mild conditions.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive studies conducted by the present inventors in view of the above-mentioned state of the art, an electrode using a specific metal as a positive electrode is a dihalosilane having a hydroxyl group-protected phenol group. When using for reaction,
Since the reaction can be carried out under room temperature conditions and the polysilane having a phenol group can be synthesized in a significantly higher yield than the conventional method, the problems of the prior art can be substantially solved, or Or it was found to be significantly reduced.

That is, the present invention provides the following method for producing a polysilane having a phenol group.

1. A method for producing a polysilane having a phenol group, which comprises the general formula (1)

[0008]

[Chemical 6]

(Wherein R ¹ is an alkoxyalkyl group,
It represents a trialkylsilyl group or a benzyl group. R
² represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group. X's are the same or different and each represents a halogen atom. m is 0-10. The position of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group is the meta position or the para position. ) Is subjected to an electrode reaction using a specific metal as an anode, the general formula (2)

[0010]

[Chemical 7]

(In the formula, the positions of R ¹ , R ² and m, and the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group are the same as above corresponding to the starting materials; n is 10 to 10,000. ) A method for producing a polysilane having a phenol group having a protected hydroxyl group. 2. A method for producing a polysilane having a phenol group, which comprises the general formula (1)

[0012]

[Chemical 8]

(Wherein R ¹ is an alkoxyalkyl group,
It represents a trialkylsilyl group or a benzyl group. R
² represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group. X's are the same or different and each represents a halogen atom. m is 0-10. The position of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group is the meta position or the para position. ) Is subjected to an electrode reaction using a specific metal as an anode, the general formula (2)

[0014]

[Chemical 9]

(Wherein R ¹ , R ² and m, and the positions of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group are the same as above corresponding to the starting materials; n is 10 to 10,000) After the polysilane represented by the general formula (3) is obtained, the polysilane represented by the general formula (3)

[0016]

[Chemical 10]

(Wherein R ² and m are the same as above corresponding to the starting material: the position of the hydroxyl group corresponds to the position of the alkoxyalkoxy group, trialkylsiloxy group or benzyloxy group of the starting material. And the same as described above; n is 10 to 10,000.) For producing a polysilane having a phenol group.

In the following, if necessary, the inventions of the first and second aspects are referred to as the first invention and the second invention of the present application, respectively. Further, both are collectively referred to as the present invention.

In the first invention of the present application, the halosilane used as the starting material is represented by the general formula (1)

[0020]

[Chemical 11]

It is a dihalosilane having a phenolic group having a protected hydroxyl group.

In the dihalosilane of the general formula (1), R
¹ represents an alkoxyalkyl group, a trialkylsilyl group or a benzyl group. R ² represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group or an amino group.
X represents the same or different halogen atoms. m
Is an integer of 0 to 10. An alkoxyalkoxy group,
The position of the trialkylsiloxy group or the benzyloxy group is the meta position or the para position.

The reaction product in the first invention of the present application has the general formula (2):

[0024]

[Chemical 12]

It is a polysilane having a phenol group having a protected hydroxyl group.

In the compound of the general formula (2), R ¹ , R
^{The positions of 2} and m, as well as an alkoxyalkoxy group, a trialkylsiloxy group or a benzyloxy group, are the same corresponding to the compound of the general formula (1) which is the starting material. Further, n is 10 to 10,000.

Further, the reaction product in the second invention of the present application has the general formula (3):

[0028]

[Chemical 13]

It is a polysilane having a phenol group represented by:

In the compound of the general formula (3), R ¹ , R
² and m are the same corresponding to the compound of the general formula (1) which is also a starting material. In addition, n is 10 to 10
It is 000. The positions of the hydroxyl groups are the same as those of the alkoxyalkoxy group, trialkylsiloxy group or benzyloxy group in the starting material, corresponding to these positions.

In the compounds of the general formulas (1), (2) and (3), when R ² is an alkyl group, the number of carbon atoms is usually about 1 to 10 and the number of carbon atoms is 1 to 6. The thing is more preferable. As the aryl group, a phenyl group, a phenyl group having at least one alkyl group having 1 to 6 carbon atoms as a substituent, a p-alkoxyphenyl group, m-
Examples thereof include an alkoxyphenyl group. Examples of the alkoxy group and the alkoxy group as a substituent of the phenyl 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 ² is an amino group, at least one of its hydrogen atoms is
It may be substituted with a functional group similar to the above such as an alkyl group, an aryl group and an alkoxy group.

In the compounds represented by the general formulas (1) and (2), R ¹ is a protecting group for a phenol group, and is an alkoxyalkyl group, a trialkylsilyl group or a benzyl group. Examples of the alkoxyalkyl group include those in which one of the hydrogen atoms of an alkyl group having 1 to 6 carbon atoms is substituted with an alkoxy group having about 1 to 10 carbon atoms, and among these, a methoxymethyl group and a methoxyethyl group are preferable. Examples of the trialkylsilyl group include a trimethylsilyl group, a t-butyldimethylsilyl group and a dimethylisopropylsilyl group.

In the compound represented by the general formula (1), X is the same or different halogen atom (Cl,
Br, I). Cl is more preferable as the halogen atom.

In the first invention of the present application, the dihalosilane represented by the general formula (1) is preferably as pure as possible, and for example, it is preferably distilled before use.

In the reaction in the first invention of the present application, the dihalosilane represented by the general formula (1) is used by dissolving it in a solvent. As the solvent, aprotic solvents can be widely used, and more specifically, propylene carbonate, acetonitrile, dimethylformamide, dimethylsulfoxide, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, p-dioxane. , Tetrahydrofuran, methylene chloride and the like. These solvents are
They can be used alone or as a mixture of two or more kinds. As the solvent, 1,2-dimethoxyethane and tetrahydrofuran are more preferable. If the concentration of dihalosilane in the solvent is too low, the current efficiency will decrease, whereas if it is too high, the supporting electrolyte may not dissolve. Therefore, the concentration of dihalosilane in the solvent is usually about 0.01 to 3 mol / l, more preferably about 0.05 to 1.5 mol / l.

The supporting electrolyte used in the first invention of the present application includes alkali metal perchlorates such as sodium perchlorate and lithium perchlorate: tetraalkylammonium perchlorate such as tetra-n-butylammonium perchlorate: Examples thereof include tetraalkylammonium chloride such as tetra-n-butylammonium chloride. These supporting electrolytes may be used alone or in combination of two or more kinds. Among these supporting electrolytes, lithium perchlorate is most preferable. If the concentration of the supporting electrolyte is too low, the reaction does not proceed sufficiently because the ionic conductivity given to the reaction solution is low, whereas if it is too high, an excessive current flows and the reaction is necessary for the reaction. The electric potential cannot be obtained. Therefore, the concentration of the supporting electrolyte in the solvent is usually about 0.05 to 5 mol / l, more preferably 0.1 to 5 mol / l.
~ 3 mol / l, particularly preferably 0.3-1 mol / l
It is about l.

In the first invention of the present application, Mg, Cu or Al or an alloy containing these metals as main components is used as the electrode. Mg is most preferable as the electrode material.
The shape of the electrode is not particularly limited as long as the current can be stably applied, but a rod shape, a plate shape, a cylindrical shape, a conical shape, a coiled shape of a plate shape, or the like is preferable. From the surface of the electrode,
It is preferable to remove the oxide film as much as possible in advance. The oxide film can be removed from the electrode by any method. For example, the electrode is washed with acid, then washed with ethanol and ether, and dried under reduced pressure, or the electrode is polished under a nitrogen atmosphere. It can be carried out by a method or a combination of these methods.

In carrying out the electrode reaction in the first invention of the present application, the dihalosilane represented by the general formula (1) and the supporting electrolyte are housed together with a solvent in a sealable reaction container in which an electrode is installed, preferably mechanically. Alternatively, the electrode reaction is performed by supplying a predetermined amount of current while magnetically stirring. The reaction vessel may have a dry atmosphere, but a dry nitrogen or inert gas atmosphere is more preferable. The energization amount is usually about 1 F / mol or more based on the halogen atom in the dihalosilane, and the molecular weight can be controlled by adjusting the energization amount. The reaction time may differ depending on the amount of the raw material dihalosilane, the resistance of the electrolytic solution related to the amount of the supporting electrolyte, the molecular weight of the desired polysilane, etc., and may be appropriately determined as necessary. Further, in order to shorten the reaction time, ultrasonic waves may be applied to the reaction container or the reaction solution.
The method of irradiating ultrasonic waves during the electrode reaction is not particularly limited, but a method of housing the reactor in an ultrasonic bath for irradiation, a method of charging an ultrasonic oscillator in a reaction vessel and performing irradiation Are exemplified. The frequency of ultrasonic waves is 10 to 70 kH
It is preferably about z. The output of ultrasonic waves may be appropriately determined according to the reaction conditions such as the type of raw material, the amount of reaction solution, the shapes and sizes of the reaction vessel and the electrode, the electrode material and the surface area. 01
It is in the range of about 24 kW. By such ultrasonic irradiation, the reaction time is significantly shortened to about 1/3 to 2/3 of that in the case where ultrasonic waves are not irradiated.

Further, during the electrode reaction, a metal salt (for example, MgCl ₂ ) may adhere to the cathode and cause a voltage increase. In such a case, by switching the polarities of the electrodes at regular time intervals, it is possible to remove the adhered metal salt and suppress the voltage rise. By switching the electrode polarity, the voltage value can be reduced to about 1/2 to 1/3 as compared with the case where it is not performed. The polarity is normally switched at intervals of about 1 second to 10 minutes, more preferably at intervals of about 10 seconds to 1 minute. The temperature during the reaction may be within the temperature range not higher than the boiling point of the solvent used. In the present electrode reaction, there is no need to use a diaphragm which is indispensable in a normal electrode reduction reaction, and the operation is simple and advantageous.

In the above electrode reaction, it is desirable to remove water in the solvent and the supporting electrolyte in advance in order to suppress the side reaction of the dihalosilane represented by the general formula (1) with water. For example, when tetrahydrofuran or 1,2-dimethoxyethane is used as the solvent, it is preferable to previously dry it with sodium-benzophenone ketyl or the like. Further, in the case of the supporting electrolyte, it is preferable to dry by heating under reduced pressure or to remove water by adding a substance that easily reacts with water and can be easily removed (for example, trimethylchlorosilane).

In the second invention of the present application, the protecting group R ¹ is removed from the polysilane represented by the general formula (2) obtained by the electrode reaction of the dihalosilane represented by the general formula (1) in the first invention of the present application. In order to remove the protecting group R ^{1 of the} polysilane represented by the general formula (2), when R ¹ is an alkoxyalkyl group and a benzyl group, deprotection is carried out in a tetrahydrofuran-alcohol mixed solvent using a protonic acid as a catalyst. . At this time, methanol, ethanol, isopropanol and a mixture thereof can be used as the alcohol. As such a protic acid, hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid or the like can be used. When R ¹ is a trialkylsilyl group, it can be removed by a fluorine ion or an alkali catalyst in addition to the above method. Tetrabutylammonium fluoride, hydrofluoric acid, cesium fluoride or the like can be used as the compound that supplies fluorine ions. Potassium carbonate or the like can be used as the alkali catalyst.

[0042]

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

(A) The polysilane having a phenol group can be synthesized in a good yield as compared with the conventional method.

(B) Since no alkali metal is used, polysilane can be produced safely and easily even in industrial scale production.

(C) By adjusting the amount of electricity supplied,
The molecular weight of the polysilane produced can be controlled.

(D) Since a stable and safe substance is used as the electrode, polysilane can be easily and safely produced without danger of environmental pollution.

(E) Oxygen insertion reaction into the polymer main chain due to the formation of Si-O-Si bond in the skeleton can be significantly suppressed.

(F) Since it is not necessary to use a diaphragm, the diaphragm is not clogged and the operation is simple.

(G) The polysilane having a phonol group obtained by the present invention can be prepared by the known method described above (for example, Ma
cromolecules 1989, 22 , 2933)) has higher solubility in organic solvents and excellent film-forming properties than conventional polysilanes having a phenol group and produced by the method described in 1989.

[0050]

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 × 1 cm × 5 cm;
After washing with dilute hydrochloric acid, washing with ethanol and acetone, drying under reduced pressure, and polishing under a nitrogen atmosphere,
Inner volume 30 with 2 pieces (excluding oxide film on the surface)
Anhydrous lithium perchlorate (1.0 g) was placed in a 3-ml flask (hereinafter referred to as a reactor), heated and decompressed to 1 mmHg to dry the lithium perchlorate, and then deoxygenated dry nitrogen was placed in the reactor. 20 ml of tetrahydrofuran which had been introduced into and further dried with sodium-benzophenone ketyl in advance.
Was added. To this, 1.6 g of p-methoxymethoxyphenyldichlorophenylsilane was added by a syringe. This reactor was immersed in an ultrasonic cleaner having an output of 60 W and a frequency of 47 KHz, and the reactor was kept at room temperature by a cooler while being energized by a constant current power supply. At that time, a commutator was used to convert the polarities of the two electrodes every 15 seconds, and electricity was supplied for 18 hours so that the amount of electricity supplied was 4 F / mol based on the chlorine atom in the raw material.

After completion of the reaction, the reaction solution was treated with 1N hydrochloric acid 100m.
After addition to 1 liter, it was extracted with ether and reprecipitated with poor solvent ethanol (100 ml) and good solvent benzene (2 ml).

As a result, polysilane in which the phenol group was protected by a methoxymethyl group (weight average molecular weight = 6660 by light scattering measurement method) was obtained in a yield of 28%.

Then, this polysilane was added to 50 ml of a mixed solvent of tetrahydrofuran: isopropanol = 1: 1, 0.5 ml of concentrated hydrochloric acid was added thereto, and the mixture was stirred at room temperature for 3 hours.

After completion of the reaction, extraction with ether made it possible to quantitatively obtain a polysilane having a weight average molecular weight of 5720 and having a phenol group.

Example 2 A reaction was carried out in the same manner as in Example 1 except that 0.5 g of m-methoxymethoxyphenyldichlorophenylsilane was used as the raw material represented by the general formula (1). As a result, a polysilane having a phenol group represented by the general formula (3) could be obtained corresponding to the raw material.

Example 3 m- (t-butyldimethylsiloxy) phenylmethyldichlorosilane 2.0 as a raw material represented by the general formula (1)
The electrode reaction was carried out in the same manner as in Example 1 except that g was used. As a result, the polysilane represented by the general formula (2) could be obtained corresponding to the raw material.

Then, the obtained polysilane (2) is stirred in tetrahydrofuran at room temperature for 3 hours in the presence of tetrabutylammonium fluoride to obtain a polysilane (3) having a phenol group corresponding to the raw material. did it.

Example 4 An electrode reaction was carried out in the same manner as in Example 1 except that Al (1 cm × 1 cm × 5 cm) was used as the electrode. as a result,
The same polysilane (3) having a phenol group as in Example 1 could be obtained.

Example 5 An electrode reaction 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, the same polysilane (3) having a phenol group as in Example 1 could be obtained.

Example 6 The electrode reaction was carried out in the same manner as in Example 1 except that 15 ml of 1,2-dimethoxyethane which had been previously dried with sodium-benzophenone ketyl was used as the solvent. As a result, the same polysilane (3) having a phenol group as in Example 1 could be obtained.

[0062]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryoichi Nishida 4-1-2, Hirano-cho, Chuo-ku, Osaka City, Osaka Prefecture Osaka Gas Co., Ltd. (72) Hiroaki Murase, 4-chome, Hirano-cho, Chuo-ku, Osaka-shi, Osaka No. 1 and 2 in Osaka Gas Co., Ltd.

Claims (2)

[Claims] 1. A method for producing a polysilane having a phenol group, which comprises a compound represented by the general formula (1): (In the formula, R ¹ represents an alkoxyalkyl group, a trialkylsilyl group or a benzyl group. R ² represents a hydrogen atom,
It represents an alkyl group, an aryl group, an alkoxy group or an amino group. X's are the same or different and each represents a halogen atom. m is 0-10. The position of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group is the meta position or the para position. By subjecting the dihalosilane represented by the formula (4) to an electrode reaction using a specific metal as an anode, a compound represented by the general formula (2): (In the formula, the positions of R ¹ , R ² and m, as well as the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group are the same as described above depending on the starting material;
Is 10 to 10,000. ) A method for producing a polysilane having a phenol group having a protected hydroxyl group. 2. A method for producing a polysilane having a phenol group, which comprises a compound represented by the general formula (1): (In the formula, R ¹ represents an alkoxyalkyl group, a trialkylsilyl group or a benzyl group. R ² represents a hydrogen atom,
It represents an alkyl group, an aryl group, an alkoxy group or an amino group. X's are the same or different and each represents a halogen atom. m is 0-10. The position of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group is the meta position or the para position. By subjecting the dihalosilane represented by the formula (4) to an electrode reaction using a specific metal as an anode, a compound represented by the general formula (2): (Wherein R ¹ , R ² and m, and the positions of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group are the same as above corresponding to the starting materials; n
Is 10 to 10,000. ), A polysilane represented by the general formula (3): (In the formula, R ² and m are the same as above corresponding to the starting material; the position of the hydroxyl group corresponds to the position of the alkoxyalkoxy group, the trialkylsiloxy group or the benzyloxy group of the starting material, and Is the same as; n is 10
It is from 1 to 10,000. ) A method for producing a polysilane having a phenol group represented by: