JPH0753721A - Pyrrolyl group-pendant polysilane and its preparation - Google Patents

Abstract

PURPOSE:To prepare a pyrrolyl group-pendant polysilane of a given formula improved in electroconductivity by reacting a diorganohalogenosilane with a pyrrolyl group-contg. dihalogenosilane. CONSTITUTION:An alkali metal such as Na is added to and stirred in an inert solvent such as toluene in an atmosphere of N2 to prepare a dispersion, to which a diorganohalogenosilane of the formula: R<1>R<2>SiX2 such as dimethyldichlorosilane, and a pyrrolyl group-contg. dihalogenosilane of the formula: R<3>R<4>SiX2, such as 3-(N-pyrrolyl)propylmethyldmchloro-silane, are added, followed by effecting a reaction at a temp. of at least 100 deg.C. After the completion of the reaction, the liquid reaction mixture is concentrated to precipitate a product to thereby obtain a pyrrolyl group-pendant polysilane of the formula I [wherein R<1> to R<4> are each H or a monovalent org. group; at least one of R<3> and R<4> is a pyrrolyl group-contg. monovalent hydrocarbon group of the formula II (wherein R<5> and R<6> are each H, an alkyl, or the like; and (p) is 0 to 12); X is a halogen atom; 0<=k<1; 0<m<=1; k+m=1; and n>6].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to polysilanes having a pyrrolyl group as a substituent and useful as a photoconductive material or a conductive material, and a method for producing the same.

[0002]

2. Description of the Related Art Polysilane has hitherto been recognized as useful as a resist material in the field of microelectronics and as a photoconductor in optoelectronics.

Initially, such polysilanes were mainly those having an alkyl group represented by a methyl group or a phenyl group as a substituent (R. West et al.,
J. Am. Chem. Soc. , 103, 7352 (1
981)).

Then, hydrogen as a substituent, polysilane having a substituent containing a reactive carbon-carbon double bond,
Since polysilanes having a halogenated alkyl group have been synthesized and it has become possible to crosslink polysilanes, expectations for their applications have increased (R. West et.
al. J. Organomet. Chen. , 30
0,327 (1986).

In recent years, as other substituents, polysilane having a silyl group introduced (Japanese Patent Laid-Open No. 63-12636) and a phenolic substituent having been introduced have been reported to be applied to a resist material. Kaisho 63-113
No. 021).

Further, the present applicant has paid attention to the photoconductivity and conductivity of polysilane, and proposed a polysilane whose photodegradability is suppressed by introducing a substituent containing a carbazolyl group into polysilane (Japanese Patent Laid-Open No. Hei 10 (1999) -242242). No. 5-43702).

However, there is a demand for polysilanes having higher conductivity and wider applicability of polysilanes.

[0008]

Means for Solving the Problems and Actions The inventors of the present invention have conducted extensive studies in order to meet the above demands, and as a result, have shown the diorganohalogenosilane represented by the following general formula (3) and the following general formula (4). By reacting a pyrrolyl group-containing dihalogenosilane in the presence of an alkali metal in an inert solvent, novel pyrrolyl group pendant polysilanes represented by the following general formula (1) can be obtained. The contained polysilanes have electric conductivity higher than that of conventional polysilanes, and since the pyrrolyl group itself has the polymerizability of the pyrrole ring, the polysilane is used as a raw material for the polysilane-containing crosslinkable composition. The inventors have found that the above can be achieved, and have completed the present invention.

[0009]

[Chemical 3]

Accordingly, the present invention provides a pyrrolyl group pendant polysilane represented by the general formula (1), a diorganohalogenosilane represented by the general formula (3) and a pyrrolyl group represented by the general formula (4). Provided is a method for producing the above-mentioned pyrrolyl group pendant polysilanes, which comprises reacting the contained dihalogenosilane in an inert solvent in the presence of an alkali metal.

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

[0012]

[Chemical 4]

In the above formula, R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom or a monovalent organic group, and examples of the monovalent organic group include carbon atoms such as an alkyl group, an aryl group and an aralkyl group. Examples include monovalent hydrocarbon groups having a number of 1 to 12 and pyrrolyl group-containing monovalent hydrocarbon groups represented by the following formula (2). At least one of R ³ and R ⁴ is represented by the following formula (2). Is a monovalent hydrocarbon group containing a pyrrolyl group.

[0014]

[Chemical 5] (However, in the formula, R ⁵ and R ⁶ are a hydrogen atom, an alkyl group or an aryl group, and p is an integer of 0 to 12.)

The alkyl group has 1 to 12 carbon atoms.
Examples thereof include a lower alkyl group, and an aryl group having a carbon number of 6 to 12 is exemplified, and a phenyl group and the like are exemplified.

Further, k and m are 0 ≦ k <1, 0 <m ≦ 1,
k + m = 1, and n, which indicates the degree of polymerization, is an integer of 6 or more. In order to fully exhibit the characteristics of the pyrrolyl group pendant polysilanes of the present invention, a higher degree of polymerization is preferred.

The polysilanes of the formula (1) of the present invention include, as described above, a diorganohalogenosilane represented by the following general formula (3) and a pyrrolyl group-containing dihalogenosilane represented by the following general formula (4). It can be produced by reacting in the presence of an alkali metal in an inert solvent.

R ¹ R ² SiX ₂ (3) R ³ R ⁴ SiX ₂ (4) (wherein R ^{1 to} R ⁴ have the same meanings as described above, and X is a halogen atom).

Here, as the starting material, the pyrrolyl group-containing dihalogenosilane represented by the general formula (4) is, for example, N-alkenylpyrrole and (organo) dihalogenohydrosilane mixed at a molar ratio of 1 to 1.5. Then, it can be synthesized by an addition reaction. In this case, the addition reaction is preferably carried out in the presence of an addition reaction catalyst such as chloroplatinic acid. The reaction conditions are not particularly limited, but are 0-10
It is desirable to set the temperature to 0 ° C. for 1 to 5 hours. The pyrrolyl group-containing dihalogenosilane may be either a monopendant type or a dipendant type.

As the alkali metal used in the reaction of the halogenosilanes of the above formulas (3) and (4), for example, lithium, potassium, potassium sodium alloy, sodium and the like can be used, among which sodium is preferably used. . The addition amount of this alkali metal is calculated by the formula (3)
It is preferable that the amount of the dihalogenosilanes of the formula (4) is 2 to 3 mol, and particularly 2 to 2.1 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 (3) and (4).

The reaction conditions of the dihalogenosilanes of the above formulas (3) and (4) 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, in the production method of the present invention, an alkali metal is added to an inert solvent, heated and stirred, and then a mixture of dihalogenosilanes of the formulas (3) and (4) is added dropwise. The reaction proceeds exothermically and ends when the alkali metal is consumed.

In this case, by using the dihalogenosilanes of the formulas (3) and (4), a one-dimensional polymer or cyclic compound is produced. W. Weidman et al.
Am. Chem. Soc. , (1988). 110,2
As reported in 342, trifunctional trihalosilanes may be added, which can also give networked polysilanes. Further, it is also possible to use halosilanes containing a carbon-carbon unsaturated bond in the main chain skeleton in advance, and thereby a carbon-carbon unsaturated bond can be introduced into the polysilane skeleton.

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.

The pyrrolyl group pendant polysilanes of the present invention thus obtained have a higher electric conductivity than ordinary methylphenyl polysilanes, such as [(Me _{2
Si) 0.75 (Py- (CH 2} ) 3 -SiMe) 0.25]
The electric conductivity when iodine of _n (wherein Py represents a pyrrolyl group and Me represents a methyl group; the same applies hereinafter) was 4.5 × 10 ⁻³ S / cm, and the doping (MePhSi ) _N (in the formula, Ph represents a phenyl group; the same applies hereinafter) has an electric conductivity of 10 ⁻⁶ S / cm, but has a very high electric conductivity. Further, by utilizing the polymerizability of the pyrrole ring, it can be used as a raw material of the polysilane-containing crosslinkable composition. Therefore, it can be suitably applied to photoconductive materials and conductive materials.

[0027]

INDUSTRIAL APPLICABILITY The pyrrolyl group pendant polysilanes of the present invention have high electric conductivity and broaden the range of application of polysilanes to conductive materials and the like.

Further, according to the production method of the present invention, such a pyrrolyl group pendant polysilane can be industrially advantageously produced.

[0029]

EXAMPLES Hereinafter, the present invention will be specifically shown by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Example 1 First, 3- (N-pyrrolyl)
Propylmethyldichlorosilane was synthesized as follows.
Under a nitrogen atmosphere, N-allylpyrrole 15.6 g (146
Mmol), toluene 30 g, and chloroplatinic acid / butanol solution 0.1 g (platinum content 2.0 wt%) were placed in a flask and heated to 75 ° C., and stirring was started. 20.7 g (180 mmol) of methyldichlorosilane was added dropwise over 40 minutes. After heating and stirring for 2 hours, 27.8 g (yield 86%) of 3- (N-pyrrolyl) propylmethyldichlorosilane represented by the following formula was obtained by distillation. Mass spectrometry confirmed that the molecular ion mass was 221 and that the target compound was obtained.

[0031]

[Chemical 6]

Next, as shown below, [(MePhSi)
_{0.83 (Py- (CH 2) 3} -SiMe) 0.17] was synthesized _n.

Metallic sodium 3.0 g under nitrogen atmosphere
Toluene (30 g) was added to (130 mmol), and the temperature was 110 ° C.
The temperature was raised to 1, and the mixture was vigorously stirred to prepare a sodium dispersion.

2.2 g (10 mmol) of 3- (N-pyrrolyl) propylmethyldichlorosilane and 9.55 g (5) of methylphenyldichlorosilane were added to this dispersion.
(0 mmol) was added over 15 minutes, and the mixture was stirred at 110 ° C. for 4 hours. After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol 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. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer. The precipitate was filtered off and dried in vacuum to obtain 0.5 g of pyrrolyl pendant polysilane represented by the above formula as a white precipitate.

According to GPC analysis, the weight average molecular weight of this polymer was 8,800 in terms of polystyrene. In addition, the ultraviolet absorption maximum derived from polysilane (λ _max = 3
36 nm) was confirmed.

[Embodiment 2] As shown below, [(MePhS
_{i) 0.91 (Py- (CH 2} ) 3 -SiMe) 0.09] was synthesized _n.

3.0 g of metallic sodium under a nitrogen atmosphere
Toluene (30 g) was added to (130 mmol), and the temperature was 110 ° C.
The temperature was raised to 1, and the mixture was vigorously stirred to prepare a sodium dispersion.

1.1 g (5 mmol) of 3- (N-pyrrolyl) propylmethyldichlorosilane and 9.55 g (50) of methylphenyldichlorosilane were added to this dispersion.
(Mmol) was added over 10 minutes, and the mixture was stirred at 110 ° C for 4 hours. After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol 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. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer.
The precipitate was filtered off and dried in vacuum to obtain 0.84 g of the pyrrolyl pendant polysilane represented by the above formula as a white precipitate.

According to GPC analysis, the weight average molecular weight of this polymer was 6,400 in terms of polystyrene. In addition, the ultraviolet absorption maximum derived from polysilane (λ _max = 3
37 nm) was confirmed.

[Example 3] As shown below, [(Me ₂ Ph
_{Si) 0.75 (Py- (CH 2} ) 3 -SiMe) 0.25] was synthesized _n.

2.34 g of sodium metal under a nitrogen atmosphere
Toluene (20 g) was added to (100 mmol), and the temperature was 110 ° C.
The temperature was raised to 1, and the mixture was vigorously stirred to prepare a sodium dispersion.

2.1 g (10 mmol) of 3- (N-pyrrolyl) propylmethyldichlorosilane and 3.87 g (30 mmol) of dimethyldichlorosilane were added to this dispersion in 15 minutes, and the mixture was stirred at 110 ° C. for 5 hours.
After completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol 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. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer. The precipitate was filtered off and dried under vacuum to obtain 0.4 g of pyrrolyl pendant polysilane represented by the above formula as a white precipitate.

According to GPC analysis, the weight average molecular weight of this polymer was 19000 in terms of polystyrene. In addition, the ultraviolet absorption maximum derived from polysilane (λ _max = 3
16 nm) was confirmed.

Reference Example The pyrrolyl group pendant polysilanes obtained in Examples 1 and 3 were doped with iodine and the electrical conductivity thereof was measured. The results are shown in Table 1. For comparison, the results of methylphenylpolysilane are also shown.

[0045]

[Table 1]

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Motoo Fukushima 3-2-1 Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa Shin-Etsu Chemical Co., Ltd. Corporate Research Center

Claims (2)

[Claims] 1. A pyrrolyl group pendant polysilane represented by the following general formula (1). [Chemical 1] 2. The following general formula (3) R ¹ R ² SiX ₂ (3) (wherein R ¹ and R ² are each a hydrogen atom or a monovalent organic group, and X is a halogen atom). ) And a diorganohalogenosilane represented by the following general formula (4) R ³ R ⁴ SiX ₂ (4) The method for producing a pyrrolyl group pendant polysilane according to claim 1, wherein the pyrrolyl group-containing dihalogenosilane represented by the formula (1) is reacted in the presence of an alkali metal in an inert solvent.