JPH1149782A - Alkylsilane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new compound suitable as a starting material for polysilanes useful as e.g. precursors for electroconductive materials, photoconductive materials and silicon carbide-based ceramics, and capable of giving a polysilane of a network structure with favorable eliminated status of carbosubstituents when pyrolyzed in a nitrogen atmosphere. SOLUTION: This new compound is shown by formula I (R is methyl or ethyl; X is H or a halogen), e.g. 2,4-dimethyl-3-trichlorosilylpentane. The compound of formula I is obtained, for example, by reaction of an organometallic of formula II (M is lithium or a magnesium halide) with a silicon tetrahalide of the formula SiX'4 (X' is a halogen) (pref. tetrachlorosilane). The above reaction is normally carried out pref. at 0-80 deg.C for 20 min to 5 h by adding a polar solvent solution of the compound of formula II to a polar solvent solution of the tetrahalosilane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkylsilane, and more particularly, to a polysilane useful as a conductive material, a photoconductive material, a photoreactive material such as a photoresist, a polymerization initiator, and a precursor of a silicon carbide ceramic. The present invention relates to an alkylsilane suitable as a starting material for obtaining

[0002]

2. Description of the Related Art In recent years, attempts have been made to use polysilanes as a material for a conductive material or as a material for a photoconductive material. For example, linear polymethylphenylsilane
By doping F _5, a highly conductive material is obtained. Attempts have also been made to obtain conductive and photoconductive materials by thermally decomposing polysilane. For example, after thinning polyphenylsilin having a molecular structure of a network, a SiC thin film can be obtained by pyrolysis in a vacuum, and by performing this pyrolysis at 600 ° C., E _g. There is also a report that a semiconductor thin film of _opt = 1.1 eV can be obtained (Chem. Lett., 1101 (199).
1)). However, polyphenylsilin is not suitable as a raw material for producing a photoconductive material or the like because the carbon substituent has a low elimination property during the thermal decomposition process and a large amount of carbon remains in the material after the thermal decomposition. Further, since thermal decomposition must be performed in a vacuum, there is a regret that the cost increases even when a semiconductor thin film is obtained.

[0003]

Means for Solving the Problems The present inventor has conducted intensive studies in view of the above-mentioned conventional techniques, and as a result, has found an alkylsilane as a novel compound having excellent characteristics.
That is, the alkylsilane according to the present invention can be represented by the following general formula (1).

Embedded image (In the formula, R represents a methyl group or an ethyl group, R may be the same or different, and X represents a hydrogen atom or a halogen atom.)

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the general formula (1), R represents a methyl group or an ethyl group, and Rs may be the same or different. X represents a hydrogen atom or a halogen atom. Examples of the halogen atom include fluorine, chlorine, bromine and iodine, and chlorine is particularly preferable. General formula (1)
Listed below are specific examples of alkylsilanes included in:
2,4-dimethyl-3-silylpentane, 2,4-dimethyl-3-silylhexane, 3,5-dimethyl-4-silylheptane, 3-ethyl-5-methyl-4-silylheptane, 3,5- Diethyl-4-silylheptane, 2,
4-dimethyl-3-trichlorosilylpentane, 2,4
-Dimethyl-3-trichlorosilylhexane, 3,5-
Dimethyl-4-trichlorosilylheptane, 3-ethyl-5-methyl-4-trichlorosilylheptane, 3,5
-Diethyl-4-trichlorosilylheptane and the like.

[0005] The method for producing the alkylsilane of the present invention is not particularly limited, and various synthetic techniques can be used for the production thereof. It is on the street. In the alkylsilane represented by the general formula (1), a first method for synthesizing an alkyltrihalogenosilane in which three halogen atoms are bonded to a silicon atom comprises an organometallic compound represented by the formula (a):
This is a method of reacting with silicon tetrahalide (see formula (2)).

Embedded image

Embedded image (Wherein, R is the same as R in the general formula (1), X ′ represents a halogen atom, and M represents lithium or magnesium halide.) As the organometallic compound represented by the formula (a), , 2,4-dimethyl-3-lithiopentane, 2,4-dimethyl-3-
Lithiohexane, 3,5-dimethyl-4-lithioheptane, 3-ethyl-5-methyl-4-lithioheptane,
3,5-diethyl-4-lithioheptane and the like can be used. These organometallic compounds can be easily obtained by reacting the corresponding halogenated alkane with lithium or magnesium in an ether solvent such as diethyl ether or tetrahydrofuran. formula
As the tetrahalogenated silane to be reacted with the organometallic compound (a), various ones can be used, and tetrachlorosilane is particularly preferred. The method for carrying out the reaction of the formula (2) is not particularly limited, but usually, a solution obtained by dissolving a tetrahalogenated silane (typically, tetrachlorosilane) in a polar solvent such as ether or tetrahydrofuran is added to the solution of the formula (a). And a solution prepared by dissolving the organometallic compound in a polar solvent such as diethyl ether or tetrahydrofuran. The reaction temperature in this case is appropriately selected depending on the type and amount of the organometallic compound to be used, but is usually -20 to 100 ° C, preferably 0 to 80 ° C, and the reaction time is usually 5 minutes to 10 hours, preferably 20 minutes. ~ 5 hours. Although the charge composition of the reaction raw material can be arbitrarily selected, the molar ratio of the organometallic compound of the formula (a) / tetrahalogenated silane is usually 0.5 to 1.2, preferably 0.8 to 1. It is desirable to set the range to 1. After the completion of the reaction, by-product salts are separated from the reaction mixture by filtration, and the filtrate is distilled to obtain an alkyltrihalogenosilane as a target product.

A second method for synthesizing an alkyl trihalogenosilane is a method of reacting an olefin with a trihalogenosilane in the presence of a radical initiator to hydrosilylate the olefin (see formula (3)).

Embedded image (In the formula, R is the same as R in the general formula (1), and X ′ represents a halogen atom.) As the olefin in this reaction, 2,4-dimethyl-
2-pentene, 2,4-dimethyl-2-hexene, 3,
5-dimethyl-3-heptene, 3-ethyl-5-methyl-3-heptene, 3,5-diethyl-3-heptene and the like can be used, and various trihalogenosilanes can be used. However, trichlorosilane is particularly preferred. The radical initiator to be used is not particularly limited, but generally, 1,1′-azobis (isobutyronitrile) (AIBN), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2 Usually, 2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylpropane) and the like are used. . The method for carrying out the reaction of the formula (3) is not particularly limited, but usually, the olefin and the trihalogenosilane are reacted in an autoclave in the presence of a radical initiator. The reaction temperature is usually 80 ° C to 230 ° C, preferably 1 to
It is desirable to be in the range of 00 ° C to 200 ° C. The reaction time is appropriately selected depending on the reaction scale and the reaction vessel, but is usually 30 minutes to 5 days, preferably 1 hour to 100 days.
In the range of hours. Although the charge composition of the reaction raw materials can be arbitrarily selected, the olefin / trihalogenosilane molar ratio is generally 1.0 to 5.0, preferably 1.
It is in the range of 5-3.0. The amount of the radical initiator used is not particularly limited. However, usually the molar ratio of radical initiator / olefin is in the range of 0.05 to 1.0. The desired product can be easily recovered by distillation.

Next, a method for synthesizing alkyltrihydrosilane in which three hydrogen atoms are bonded to a silicon atom in the alkylsilane of the present invention represented by the general formula (1) will be exemplified. And hydrogenation of an alkyltrihalogenosilane using a metal hydride (see formula (4)).

Embedded image (In the formula, R is the same as R in the general formula (1), and X ′ represents a halogen atom.) The metal hydride used in this reaction is not particularly limited. , Lithium hydride, sodium hydride, sodium borohydride, lithium aluminum hydride and the like are used. The method for carrying out the reaction of the formula (4) can be arbitrarily selected, but generally, the corresponding alkyltrihalogenosilane is converted to an ether such as diethyl ether, dibutyl ether, tetrahydrofuran, benzenetoluene, hexane or the like. A method of reacting with a metal hydride in a solvent selected from the above hydrocarbons is desirable. The reaction temperature at this time is usually -20.
The temperature is desirably in the range of from 100C to 100C, preferably from 0C to 80C. The reaction time is appropriately selected depending on the reaction scale and the reaction vessel, but generally ranges from 5 minutes to 1 day, preferably from about 10 minutes to 4 hours. The amount of the metal hydride used is usually in the range of 0.5 to 4.0, preferably 0.7 to 2.0, in terms of the molar ratio of the metal hydride / alkyltrihalogenosilane. The target product can be recovered by inactivating excess metal hydride remaining in the reaction mixture with water or alcohol, and removing the by-product salt by filtration or washing with water and distillation.

A second method for synthesizing alkyltrihydrosilane
Is a method of reacting an olefin with a silane gas (monosilane) in the presence of a radical initiator (see formula (5)).

Embedded image (In the formula, R is the same as R in the general formula (1).) As the olefin for the reaction of the formula (5), any of the olefins described above for the reaction of the formula (3) can be used. . Although any radical initiator can be used as the radical initiator, usually, 1,1′-azobis (isobutyronitrile) (AIBN), 1,1′-azobis (cyclohexane-1-carbonitrile), , 2'-Azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylpropane) and the like are used. Although the reaction of the formula (5) can be carried out by any method, usually, an olefin is reacted with silane gas in the presence of a radical initiator using an autoclave. The reaction temperature at this time is generally in the range of 80C to 230C, preferably 100C to 200C. The reaction time is appropriately selected depending on the reaction scale and the reaction vessel.
It is 0 minute to 5 days, preferably about 1 hour to 100 hours. The molar ratio of olefin / silane at the time of the reaction is also arbitrary, but is usually from 1.0 to 5.0, preferably from 1.5 to 5.0.
It is selected in the range of 3.0. The amount of the radical initiator used can be arbitrarily selected, but is usually selected in a molar ratio of radical initiator / olefin in the range of 0.05 to 1.0. The desired product can be easily recovered by distilling the reaction mixture. As described above, the typical example of the method for producing an alkylsilane according to the present invention has been described, but the method for producing an alkylsilane according to the present invention is not limited thereto.

[0009]

The alkylsilane of the present invention represented by the above general formula (1) can be used as a precursor of a photoreactive material such as a conductive material, a photoconductive material, a photoresist, or a polymerization initiator and silicon carbide. It is useful as a monomer when obtaining a polysilane that can be used as a precursor of a base ceramic. The polysilane obtained from the alkylsilane of the present invention is a polysilane having a network structure of a network, and its carbon substituent has good desorbability when thermally decomposed under a nitrogen or argon atmosphere. Has features.

[0010]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Example 1 55 g of 2,4-dimethyl-3-pentene was placed in a 1-liter autoclave equipped with a stirrer under a nitrogen atmosphere of 2,4-dimethyl-3-trichlorosilylpentane.
(0.56 mol) and 148 g of trichlorosilane (1.
1 mol) and 1,1′-azobis (cyclohexane-1)
-Carbonitrile) (17 g, 70 mmol) was added, and the reaction was carried out at a reaction temperature of 130 ° C for 4 days. The obtained reaction solution was purified by distillation to obtain 117 g (0.50 mol) of 2,4-dimethyl-3-trichlorosilylpentane. The structure was confirmed by ¹ H-NMR. Yield: 89%, Boiling point: 110-120 ° C / 80 mmHg ¹ H-NMR spectrum (CDCl ₃ ) 2.29 (m, 2H, ΔCH, J = 4.0, J = 7.
0) 1.38 (t, 1H, = CHSi J = 4.0) 1.17,1.14 (d × 2,12H, -CH 3, J =
7.0) Mass spectrometry spectrum (mass spectrum) C ₇ H ₁₅ SiCl ₃ calc: C 35.99, H 6.47, Si 12.02, Cl 45.52 obs: C 36.22, H 6.41, Si 12.17, Cl 45.20 Example 2 2,4- Under a nitrogen atmosphere of dimethyl-3-silylpentane, 50 g (1.3 mol) of lithium aluminum hydride and 1 liter of diethyl ether were placed in a 1 liter four-necked flask equipped with a stirrer, a reflux condenser and a dropping funnel, 2,4-dimethyl-3-trichlorosilylpentane 1 obtained in Example 1 while stirring
A mixture of 17 g (0.50 mol) of diethyl ether (200 ml) was added dropwise over 2 hours. After the completion of the dropwise addition, the mixture was heated under reflux for 2 hours. After completion of the reaction, 40 ml of water was added dropwise under ice-cooling, 1 liter of dilute hydrochloric acid and 500 ml of diethyl ether were sequentially added. The organic layer was separated, and washed with 500 ml of water × 3. The organic layer was dried over anhydrous magnesium sulfate, filtered,
Subsequently, the residue was purified by distillation to obtain 39 g (0.30 mol) of 2,4-dimethyl-3-silylpentane. Structure confirmed ¹ H-
Performed by NMR. Yield: 60%, Boiling point: 125-128 ° C ¹ H-NMR spectrum (CDCl ₃ ) 3.44 (d, 3H, -SiH3, J = 4.0) 1.91 (oxtet, 2H, ΔCH, J) = 6.6) 0.97, 0.95 (d × 2, 12H, -CH3, J =
6.6) 0.75-0.87 (m, 1H, = CHSi) Mass spectrum Example 3 77 g of 3,5-diethyl-3-heptene was placed in a 1-liter autoclave equipped with a stirrer under a nitrogen atmosphere of 3,5-diethyl-4-trichlorosilylheptane.
(0.50 mol) and 134 g of trichlorosilane (1.
0 mol) and 1,1′-azobis (cyclohexane-1)
(Carbonitrile) (24 g, 0.10 mol) was added, and the reaction was carried out at a reaction temperature of 130 ° C. for 5 days. The obtained reaction solution was purified by distillation to obtain 80 g (0.28 mol) of 3,5-diethyl-4-trichlorosilylheptane. The structure was confirmed by ¹ H-NMR. Yield: 55%, boiling point: 130 to 135 ° C / 10 mmHg ¹ H-NMR spectrum (CDCl ₃ ) 2.21 to 2.39 (m, 2H, ≡CH) 1.65 to 1.83 (m, 8H, = CH2) 1.38 (t, 1H, = CHSi, J = 4.1) 1.14, 1.07 (tx2, 12H, -CH3, J =
6.8) Mass spectrum C ₁₁ H ₂₃ SiCl ₃ calc: C 45.60, H 8.00, Si 9.69, Cl 36.71 obs: C 45.29, H 8.13, Si 9.85, Cl 36.73 Example 4 3,5-diethyl-4-silyl In a heptane nitrogen atmosphere, 27 g (0.71 mol) of lithium aluminum hydride and 500 ml of diethyl ether were placed in a 1-liter four-necked flask equipped with a stirrer, a reflux condenser and a dropping funnel, and stirred while stirring. 80 g (0.28 mol) of 3,5-diethyl-4-trichlorosilylheptane obtained in 3
00 ml of the mixture was added dropwise over 2 hours. After the completion of the dropwise addition, the mixture was heated under reflux for 2 hours. After the completion of the reaction, 30 ml of water was added dropwise under cooling with ice, 500 ml of dilute hydrochloric acid and 500 ml of diethyl ether were sequentially added. After separating the organic layer, 500 ml of water was further added.
Washed in 3. The organic layer was dried over anhydrous magnesium sulfate, filtered, and subsequently purified by distillation to give 3,5-diethyl-4.
28 g (0.12 mol) of silylheptane were obtained. The structure was confirmed by ¹ H-NMR. Yield: 43% Boiling point: 92-98 ° C./20 mmHg ¹ H-NMR spectrum (CDCl ₃ ) 3.46 (d, 3H, —SiH3, J = 4.0) 2.02 (m, 2H, ΔCH) 1.55 to 1.80 (m, 8H, = CH2) 1.02, 0.97 (tx2, 12H, -CH3, J =
6.8) 0.71-0.82 (m, 1H, = CHSi) Mass spectrum Example 5 76 g of 3,5-dimethyl-3-heptene was placed in a 1-liter autoclave with a stirrer under a nitrogen atmosphere of 3,5-dimethyl-4-trichlorosilylheptane.
(0.60 mol) and 161 g of trichlorosilane (1.
2 mol) and 1,1′-azobis (cyclohexane-1)
-Carbonitrile) (29 g, 0.12 mol) was added, and the reaction was carried out at a reaction temperature of 130 ° C for 5 days. The obtained reaction solution was purified by distillation to obtain 92 g (0.35 mol) of 3,5-dimethyl-4-trichlorosilylheptane. The structure was confirmed by ¹ H-NMR. Yield: 58%, Boiling point: 100-110 ° C / 40 mmHg ¹ H-NMR spectrum (CDCl ₃ ) 2.21-2.39 (m, 2H, ≡CH) 1.55-1.76 (m, 8H, = CH2) 1.43 (t, 1H, = CHSi, J = 4.1) 1.08 (d, 6H, -CH3, J = 6.8) 1.05 (t, 6H, -CH3, J = 6.8) Mass spectrum C ₉ H ₁₉ SiCl ₃ calc: C 41.31, H 7.32, Si 10.73, Cl 40.64 obs: C 41.86, H 7.78, Si 10.21, Cl 40.15 Example 6 3,5-dimethyl-4-silyl In a heptane nitrogen atmosphere, 33 g (0.83 mol) of lithium aluminum hydride and 500 ml of diethyl ether were placed in a 1-liter four-necked flask equipped with a stirrer, a reflux condenser, and a dropping funnel, and stirred. 3,5-dimethyl-4-trichloro obtained in 5 Diethyl ether Riruheputan 92 g (0.35 mol) 1
00 ml of the mixture was added dropwise over 2 hours. After the completion of the dropwise addition, the mixture was heated under reflux for 2 hours. After completion of the reaction, 40 ml of water was added dropwise under ice-cooling, 500 ml of dilute hydrochloric acid and 500 ml of diethyl ether were sequentially added, and after separating the organic layer, 500 ml of water was further added.
Washed in 3. The organic layer was dried over anhydrous magnesium sulfate, filtered, and subsequently purified by distillation to give 3,5-dimethyl-4.
-22 g (0.12 mol) of silylheptane were obtained. The structure was confirmed by ¹ H-NMR. Yield: 40%, Boiling point: 90-95 ° C./100 mmHg ¹ H-NMR spectrum (CDCl ₃ ) 3.44 (d, 3H, —SiH3, J = 4.0) 1.93 (m, 2H, ΔCH) ) 1.70-1.82 (m, 8H, = CH2) 1.01 (d, 6H, -CH3, J = 6.6) 0.95 (t, 6H, -CH3, J = 6.7) 0.77-0.83 (m, 1H, = CHSi) Mass spectrum

Claims (1)

[Claims] 1. An alkylsilane represented by the following general formula (1). Embedded image (In the formula, R represents a methyl group or an ethyl group, R may be the same or different, and X represents a hydrogen atom or a halogen atom.)