JPH0959388A - Symmetry-type pyrrolyl group pendant polysilanes and their production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain polysilane compounds having excellent electric conductivity and useful for a photoconductive material, etc., by solely using a diorganohalogenosilane having a specific structure or copolymerizing with another diorganohalogenosilane. SOLUTION: The symmetry-type pyrrolyl group pendant polysilanes are expressed by the formula (R<1> is a 1-12C alkylene or arylene; R<2> and R<3> are each monofunctional hydrocarbon; Y is an N-pyrrolyl; 0<(n)<=1, 0<=(m)<1, (n+m)=1, (p)>=6) and can be obtained by solely using a diorganohalogenosilane of the formula (A): (Y-R<1> )2 SiX2 (X is a halogen), or by reacting the component A and a diorganohalogenosilane of the formula (B): R<2> R<3> SiX2 with an alkali metal in an inert solvent. The diorganohalogenosilane of the formula: Y-R<1> X to Grignard reaction by using a metallic magnesium and reacting the resultant reactant with a compound of the formula: SiX4 .

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel symmetric pyrrolyl group which is excellent in electric conductivity and can be effectively used as a photoconductive material, a conductive material, a raw material of a crosslinkable composition containing polysilane, and the like. The present invention relates to pendant polysilanes and a method for producing the same.

[0002]

2. Description of the Related Art
Most polysilanes have an alkyl group represented by a methyl group or a phenyl group as a substituent (RW
est et. al. , J. et al. Am. Chem. So
c. , 103, 7352, 1981).

Thereafter, a polysilane having a substituent containing hydrogen or a reactive carbon-carbon double bond as a substituent,
Since polysilanes having a halogenated alkyl group have been synthesized and the polysilanes can be crosslinked, the application of polysilanes to various fields is expected to be high (R. West et. Al., J. . Organom
et. Chem. , 300, 327, 1986).

Further, in recent years, it has been reported that polysilane having a silyl group introduced as another substituent (described in JP-A-63-12636) and application to a resist material by introducing a phenolic substituent. (JP-A-63-1
13021), polysilanes are expected to be applied to various fields.

[0005]

Means for Solving the Problems and Embodiments of the Invention In view of the above circumstances, the present inventor has conducted further research on polysilanes, and as a result, diorganohalogenosilane alone represented by the following general formula (2), or By reacting a diorganohalogenosilane represented by the following general formula (2) and a diorganohalogenosilane represented by the following general formula (3) with an alkali metal in an inert solvent, a diorganohalogenosilane represented by the following general formula (1) is represented. It has been found that novel symmetric pendant polysilanes having a pyrrolyl group are obtained, and these polysilanes have excellent electric conductivity and can be effectively used as photoconductive materials, conductive materials and the like.

[0006]

Embedded image (However, in the formula, R ¹ is an alkylene group having 1 to 12 carbon atoms or an arylene group, R ² and R ³ are each a monovalent hydrocarbon group,
Y is a substituted or unsubstituted N-pyrrolyl group, X is a halogen atom, and 0 <n ≦ 1, 0 ≦ m <1, n + m = 1, p ≧
It is 6. )

Incidentally, the present applicant has focused on the photoconductivity and electroconductivity of polysilane, and has developed a polysilane having suppressed photodegradability by introducing a substituent containing a carbazolyl group into polysilane. It was proposed in JP-A-5-43702. Further, polysilanes having a pyrrolyl group introduced therein have already been proposed in JP-A-7-53721.

The pyrrolyl group pendant polysilanes are expected to be excellent photoconductive materials, conductive materials, etc. in practical applications, but in order to fully exhibit their characteristics, the content of the pyrrolyl group is high. Also, a polymer having a high degree of polymerization is required.

That is, the electrical conductivity of doped dialkylpolysilanes and polysilanes having a phenyl group such as (MePhSi) _n is 10 ⁻⁸ S / cm to 10 ⁻⁶ S /.
On the other hand, in the pyrrolyl group pendant polysilane, the conductivity increases as the pyrrolyl group content increases. However, the introduction rate of the pyrrolyl group is inevitably limited in the monopyrrolyl group pendant homopolysilane.

On the other hand, the symmetrical pyrrolyl group pendant polysilanes of the above formula (1) containing a silylene unit in which two pyrrolyl groups are pendant on silicon synthesized in the present invention have a high pyrrolyl group content. Since it is possible to further improve the electrical conductivity, it is also possible to regulate the main chain by the crystallization effect of the substituent because the substituent is symmetrical.
Therefore, they have found that they can be effectively used as a photoconductive material and a conductive material, and as a raw material of a polysilane-containing crosslinkable composition, and have completed the present invention.

Accordingly, the present invention is directed to the symmetrical pyrrolyl group pendant polysilanes represented by the above formula (1), the diorganohalogenosilane alone represented by the above formula (2), or the diorganohalogenosilane represented by the above formula (2). The organohalogenosilane and the diorganohalogenosilane represented by the above formula (3) are reacted with an alkali metal in an inert solvent to produce the above formula (1).
The present invention provides a method for producing polysilanes, which comprises producing the above polysilanes.

The present invention will be described in more detail below. The symmetrical pyrrolyl group pendant polysilanes of the present invention are represented by the following general formula (1).

[0013]

Embedded image (However, in the formula, R ¹ is an alkylene group having 1 to 12 carbon atoms or an arylene group, R ² and R ³ are each a monovalent hydrocarbon group,
Y is a substituted or unsubstituted N-pyrrolyl group, and 0 <n ≦
1, 0 ≦ m <1, n + m = 1, and p ≧ 6. )

In the above formula (1), R ¹ is, for example, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group or another alkylene group having 1 to 12 carbon atoms, a phenylene group, a biphenylene group, etc. And the arylene group, and the hexylene group is particularly preferable. Further, R ² and R ³ have 1 to 12 carbon atoms, especially 1
To 6 are preferred, and specific examples thereof include an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group, an aryl group such as a phenyl group, and an alkenyl group such as a benzyl group. However, an n-hexyl group is particularly preferable. Y is a substituted or unsubstituted N-pyrrolyl group represented by the following formula (1a).

[0015]

Embedded image (However, in the formula, R ⁴ and R ⁵ are each a hydrogen atom and a carbon number of 1 to
12, preferably 1 to 5 alkyl groups, 6 to 12 carbon atoms
Represents an aryl group such as a phenyl group. )

Note that n and m are 0 <n≤1, 0≤m <1, and
Preferably 0.3 <n ≦ 1, 0 ≦ m <0.7, n + m
= 1. Further, p is an integer of 6 or more, and when used as a polymer solution, the degree of polymerization is preferably 6 ≦ p ≦ 500,000, more preferably 20 ≦ p ≦ 100,000.

The symmetric pyrrolyl group pendant polysilanes of the above formula (1) of the present invention include, for example, a diorganohalogenosilane represented by the following general formula (2) alone or a diorganohalogeno represented by the following general formula (2). It can be synthesized by reacting a silane and a diorganohalogenosilane represented by the following general formula (3) with an alkali metal in an inert solvent.

(Y-R ¹ ) ₂ SiX ₂ (2) R ² R ³ SiX ₂ (3) (R ¹ , R ² , R ³ and Y have the same meanings as described above, X is Cl, It is a halogen atom such as Br.)

In this case, dihalogenosilanes having two pyrrolyl groups of the above formula (2) pendant in an inert solvent are polymerized alone or the dihalogenosilanes (2) are polymerized.
And other dihalogenosilanes, preferably a dihalosilane monomer of the above formula (3) having two long-chain alkyl groups having 4 to 12 carbon atoms, which easily generate high molecular weight polysilane. Thus, the high-polymerization degree polysilanes of the above formula (1) containing a pendant silylene dipyrrolyl group can be synthesized. At this time, regarding the dihalogenosilanes containing a pyrrolyl group, when the pyrrolyl group is pendant only on one of the substituents, the introduction rate of the pyrrolyl group is limited, but as in the present invention, two pyrrolyl groups are introduced. Using dihalogenosilanes with pendant groups,
A pyrrolyl group is sufficiently introduced, and a high degree of polymerization polymer can be easily obtained.

As the alkali metal used for the reaction of the halogenosilanes of the above formulas (2) and (3), for example, lithium, potassium, potassium sodium alloy, sodium and the like can be used, and among them, sodium is preferably used. . The addition amount of this alkali metal is calculated by the formula (2)
It is preferable that the amount of the dihalogenosilanes of the formula (3) is 2 to 3 mol, particularly 2 to 2.5 mol per 1 mol of the total amount used. If the amount added is less than 2 mol, the reaction may not proceed sufficiently.

As the inert solvent, specifically, aromatic hydrocarbons such as toluene and xylene and aliphatic hydrocarbons such as decane, dodecane and tetralin are preferably used.
The amount used is preferably 1 to 10 times, especially 2 to 5 times the total amount of the dihalogenosilanes of the formulas (2) and (3).

The reaction conditions of the above dihalogenosilanes and the alkali metal can be appropriately adjusted, but it is preferable to carry out the reaction under a temperature condition of 100 ° C. or higher for 1 to 6 hours.

Thus, the production method of the present invention can be carried out by adding an alkali metal to an inert solvent, heating and stirring, and then dropping a mixture of dihalogenosilanes.
The reaction proceeds exothermically and ends when the alkali metal is consumed.

After completion of the reaction, excess alkali metal is deactivated with alcohol, and then the organic layer is taken out and precipitated from acetone or the like to obtain the polysilane of the formula (1) of the present invention.

Here, the dihalogenosilane of the above formula (2) is an N-pyrrolylalkyl (or aryl) represented by Y—R ¹ X (Y, R ¹ and X have the same meanings as described above). ) It can be synthesized by converting a halide to Grignard using metallic magnesium, and reacting it with a compound represented by SiX ₄ (X has the same meaning as above) such as silicon tetrachloride.

In this case, the above-mentioned Grignard formation reaction can be carried out according to a conventional method, for example, by adding magnesium to Y--
¹ to 1.2 mol is used with respect to 1 mol of R ¹ X, and this is used as T
Using a solvent such as HF dropwise Y-R ¹ X under reflux, by reacting usually about 1 to 3 hours to give a Grignard reagent. In addition, the reaction of this Grignard reagent with SiX ₄ uses about 0.5 mol of SiX ₄ with respect to ¹ mol of Y—R ¹ X, and uses 0 to 6 in a solvent such as THF.
It can be carried out by reacting at 7 ° C. for about 3 to 10 hours.

[0027]

EFFECTS OF THE INVENTION The symmetrical pyrrolyl group pendant polysilanes of the above formula (1) of the present invention are excellent in electrical conductivity, and can be used for photoconductive materials, conductive materials and polysilane-containing crosslinkable compositions. It can be effectively used as a raw material. Further, according to the production method of the present invention, the polysilanes of the above formula (1) can be produced industrially advantageously.

[0028]

EXAMPLES The present invention will be specifically described below by showing synthesis examples, examples and comparative examples, but the present invention is not limited to the following examples.

[Synthesis Example] Bis (6- (N-pyrrolyl))
Synthesis of xyl) dichlorosilane Under a nitrogen atmosphere, 1.46 g of magnesium (60 mmo)
1) and 5 g of THF were placed in a flask, and stirring was started while refluxing. 9.28 g (50 mmol) of 6- (N-pyrrolyl) hexyl chloride and 30 ml of THF were added dropwise over 30 minutes. After stirring under reflux for 3 hours, the reaction solution was returned to room temperature to obtain a black Grignard reagent. Next, in a flask prepared separately, under a nitrogen atmosphere, 4.2
5g (25mmol) and THF50g were stored. While the reaction solution was being stirred at room temperature, the Grignard reagent was added dropwise over 1 hour. After the dropping is completed, stirring and refluxing are further performed for 5 times.
I went on time. After the reaction is complete, concentrate and concentrate with 100 ml of hexane.
Is added, the insoluble salt is filtered off, and then the desired product is obtained by distillation.
2 g (yield 52%) was obtained. When mass spectrometry was performed,
A molecular ion mass of 398 was confirmed, and bis (6- (N-
It was confirmed to be pyrrolyl) hexyl) dichlorosilane.

[0030] Example 1 _{[(Py-C 6 H 12 -} ) 2 S
i] ₁ Synthesis of [n-Hex ₂ Si] ₂₀ (Py = N-pyrroli
Ru group) under a nitrogen atmosphere, 1.1 g of metallic sodium (50 mmo
15 g of toluene was added to 1), the temperature was raised to 110 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion. To this dispersion, the bis (6- (N
-Pyrrolyl) hexyl) dichlorosilane 0.4 g (1 m
mol) and di-n-hexyldichlorosilane 5.4 g (2
0 mmol) was added over 1 minute, and the mixture was stirred at 110 ° C. for 2 hours. After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of MeOH was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. 30 ml of toluene was added to the obtained viscous substance, and this solution was added to ethanol 200
The polymer was precipitated by dropwise addition to ml. The precipitate was filtered off and dried in vacuum to obtain 0.7 g of the desired product, pyrrolyl pendant polysilane, as a white precipitate. By GPC analysis, the weight average molecular weight of this polymer was 248,600 in terms of polystyrene. This polymer was dissolved in toluene and a film was formed on a glass substrate using a spin coater. After drying, the electric conductivity was measured while doping with iodine, and found to be 9 × 10 ⁻⁵ S /
cm.

[0031] Example 2 _{[(Py-C 6 H 12 -} ) 2 S
i] ₁ [n-Hex ₂ Si] ₁₀ synthesis (Py = N-pyrroli
Ru group) under a nitrogen atmosphere, 1.1 g of metallic sodium (50 mmo
15 g of toluene was added to 1), the temperature was raised to 110 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion. To this dispersion, the bis (6- (N
-Pyrrolyl) hexyl) dichlorosilane 0.8 g (2 m
mol) and di-n-hexyldichlorosilane 5.4 g (2
0 mmol) was added over 1 minute, and the mixture was stirred at 110 ° C. for 2 hours. After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of MeOH was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. 30 ml of toluene was added to the obtained viscous substance, and this solution was added to ethanol 200
The polymer was precipitated by dropwise addition to ml. The precipitate was filtered off and dried in vacuum to obtain 0.7 g of the desired product, pyrrolyl pendant polysilane, as a white precipitate. By GPC analysis, the weight average molecular weight of this polymer was 231,400 in terms of polystyrene. This polymer was dissolved in toluene and a film was formed on a glass substrate using a spin coater. After drying, the electric conductivity was measured while doping with iodine, and was 1 × 10 ⁻³ S /
cm.

[0032] Example 3 _{[(Py-C 6 H 12 -} ) 2 S
i] ₁ Synthesis of [n-Hex ₂ Si] ₂ (Py = N-pyrroli
Ru group) 0.94 g (40 mmo of sodium metal under nitrogen atmosphere
15 g of toluene was added to 1), the temperature was raised to 110 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion. To this dispersion, the bis (6- (N
-Pyrrolyl) hexyl) dichlorosilane 2.0 g (5 m
mol) and 2.7 g of di-n-hexyldichlorosilane (1
0 mmol) was added over 1 minute, and the mixture was stirred at 110 ° C. for 2 hours. After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of MeOH was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. 10 ml of toluene was added to the obtained viscous material, and this solution was added with ethanol 100
The polymer was precipitated by dropwise addition to ml. The precipitate was separated by filtration and dried in vacuum to obtain 0.4 g of the target product, pyrrolyl pendant polysilane, as a white precipitate. By GPC analysis, the weight average molecular weight of this polymer was 231,900 in terms of polystyrene. This polymer was dissolved in toluene and a film was formed on a glass substrate using a spin coater. After drying, the electric conductivity was measured while doping with iodine, and was 2 × 10 ^-2 S /
cm.

[0033] Example 4 _{[(Py-C 6 H 12 -} ) 2 S
i] Synthesis of _n (Py = N-pyrrolyl group) 0.7 g (30 mmo ) of sodium metal under nitrogen atmosphere
12 g of toluene was added to 1), the temperature was raised to 110 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion. To this dispersion, the bis (6- (N
-Pyrrolyl) hexyl) dichlorosilane 4.0 g (10
mmol) was added over 1 minute, and the mixture was stirred at 110 ° C. for 2 hours. After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of MeOH was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. 30 ml of toluene was added to the obtained viscous substance, and this solution was added to ethanol 200
The polymer was precipitated by dropwise addition to ml. The precipitate was filtered off and dried in vacuum to obtain 0.1 g of the desired product, pyrrolyl pendant polysilane, as a white precipitate. By GPC analysis, the weight average molecular weight of this polymer was 167,600 in terms of polystyrene. This polymer was dissolved in toluene and a film was formed on a glass substrate using a spin coater. After drying, the electric conductivity was measured while doping with iodine, and was 4 × 10 ^-2 S /
cm.

[Comparative Example] The electrical conductivity of methylphenylpolysilane containing no pyrrolyl group, (MePhSi) _n , was measured in the same manner and found to be 1.3 × 10 ⁻⁶ S / cm.
Was only shown.

Front Page Continuation (72) Inventor Motoo Fukushima 3-2-1 Sakado, Takatsu-ku, Kawasaki City, Kanagawa Shin-Etsu Chemical Co., Ltd. Corporate Research Center

Claims (3)

[Claims] 1. Symmetrical pyrrolyl group pendant polysilanes represented by the following general formula (1). Embedded image (However, in the formula, R ¹ is an alkylene group having 1 to 12 carbon atoms or an arylene group, R ² and R ³ are each a monovalent hydrocarbon group,
Y is a substituted or unsubstituted N-pyrrolyl group, and 0 <n ≦
1, 0 ≦ m <1, n + m = 1, and p ≧ 6. ) 2. The following general formula (2) (Y—R ¹ ) ₂ SiX ₂ (2) (wherein R ¹ is an alkylene group or an arylene group having 1 to 12 carbon atoms, and Y is a substituted or unsubstituted group). N-pyrrolyl group of
X is a halogen atom. ) Or a diorganohalogenosilane represented by the general formula (2) and a diorganohalogenosilane represented by the following general formula (3) R ² R ³ SiX ₂ (3) (wherein R ² and R ³ is a monovalent hydrocarbon group, X
Is a halogen atom. The method for producing polysilanes according to claim 1, which comprises reacting the diorganohalogenosilane represented by the formula (4) with an alkali metal in an inert solvent to produce the polysilanes according to claim 1. 3. A diorganohalogenosilane represented by the general formula (2) is a compound represented by Y—R ¹ X (Y, R ¹ and X have the same meanings as described above), using Grignard metal magnesium. 3. The production method according to claim 2, which is produced by reacting this with a compound represented by SiX ₄ (X has the same meaning as above).