JPH05310945A - Catalyst for dehydrogenative condensation of organic silicon monomer - Google Patents

Abstract

PURPOSE:To provide an easily synthesizable and handleable highly active dehydrogenative condensation catalyst and to obtain an organic silicon polymer from an organic silicon monomer in high efficiency in a short time. CONSTITUTION:The catalyst for the dehydrogenative condensation of an organic silicon monomer is composed of the 1st component consisting of a metallocene dihalide expressed by the formula Cp2MX2 (Cp is independent substituted or unsubstituted eta<5>-cyclopentadienyl group; two cyclopentadienyl groups may be bonded with each other by covalent bond through one or more atoms; M is Ti, Zr or Hf; X is F, Cl, Br or I) and the 2nd component consisting of an alkali metal, an alkaline earth metal, alloy of two or more kinds of the metals or amalgam of one or more kinds of the metals and mercury.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a catalyst used for producing an organosilicon polymer, and more particularly to a catalyst used for producing an organosilicon polymer by dehydrogenative condensation of an organosilicon monomer.

[0002]

BACKGROUND OF THE INVENTION Organosilicon polymers are used as electronic material devices, photoresist materials and photoinitiators, as well as carbonized silicon carbide fibers, silicon carbide binders, silicon carbide sheets, silicon carbide coatings and sintered silicon carbide. It is a polymer useful as a precursor for silicon materials.

Conventionally, organosilicon polymers have been synthesized by the Wurtz reaction of dihalosilane, dehydrogenative condensation of hydrosilane, or the like.

However, a method for preparing an organosilicon polymer by the Wurtz reaction of dihalosilane is known as dihalosilane 1
More than 2 moles of alkali metal is required per mole, and there is a risk of ignition of alkali metals, etc .; reaction conditions are extreme, types of side chains that can be produced are limited; molecular weight and molecular weight distribution Poor controllability; a large amount of salt is by-produced, and the yield of organosilicon polymer is 10 ~
It is as low as 50%; and a small amount of chlorine produced as a by-product remains in the organosilicon polymer (it is difficult to remove it), and the electrical properties of the organosilicon polymer deteriorate. Have.

On the other hand, in recent years, a dehydrogenative condensation reaction of hydrosilane using a transition metal complex catalyst has become known. For example, E. Henge (Hengge) et al., Cp ₂ TiMe ₂ as _{catalyst, Cp 2 ZrMe 2, Cp 2} Ti (n-
Bu) ₂ , Cp ₂ Zr (n-Bu) ₂ (where Cp represents a cyclopentadienyl group, Me represents a methyl group, and Bu represents a butyl group), and dimethyldisilane is converted into oligosilane or polysilane. It has been reported about the reaction of dehydrogenative condensation to (J. Organomet. Chem., 410, C1 to C4, 1991). As described above, a metallocene catalyst is mainly used as a catalyst used in the dehydrogenative condensation reaction. In addition, for example, Harrod et al. Use Cp ₂ TiM as a catalyst.
e ₂ , Cp ₂ ZrMe ₂ , Cp ₂ Ti (CH ₂ C
₆ H ₅ ) ₂ etc. are used to synthesize linear organosilicon polymers from organotrihydrosilane (J. Organo
met.Chem., 279, C11-C13,1985, CAN.J.CHEM.VOL.65,1804
-1809, 1987). Further, in JP-A-2-67288, a linear organosilicon polymer is synthesized by using Cp ₂ TiAr ₂ (where Ar is a substituted or unsubstituted phenyl group or naphthyl group) as a catalyst. .. These methods have advantages over the method using the Wurtz reaction in that they proceed under relatively mild conditions, that the only by-product is hydrogen, which is easy to separate, and that the yield is as high as 90% or more. ..

[0006]

In the method using the above-mentioned dehydrogenative condensation reaction, a transition metal complex catalyst is used, but these complexes require several steps of chemical reaction for synthesis,
Moreover, it was necessary to handle the catalyst used in an inert gas atmosphere.

Therefore, an object of the present invention is to provide a dehydrogenative condensation catalyst for an organosilicon monomer, which is easy to synthesize, can be handled in air, and is highly active.

[0008]

That is, the present invention provides, as a first component, a compound represented by the formula Cp ₂ MX ₂ (wherein Cp each independently represents a substituted or unsubstituted η ⁵ -cyclopentadienyl group, The two cyclopentadienyl groups may be covalently bonded to each other via one or more atoms, M being Ti,
Zr and Hf, and X represents F, Cl, Br and I. )
From the metallocene dihalide, and as a second component, an alkali metal, an alkaline earth metal or an alloy of two or more kinds thereof, or a catalyst for dehydrogenative condensation of an organosilicon monomer consisting of an amalgam of one or more of these and mercury Become.

The metallocene dihalide used as the first component is, for example, Cp ₂ TiCl ₂ , Cp ₂ ZrCl.
_{2, Cp 2 HfCl 2, Cp} 2 TiBr 2, Cp 2 Zr
Br ₂ , Cp ₂ HfBr ₂ , Cp ₂ TiI ₂ , Cp ₂ Z
rI ₂ , Cp ₂ HfI ₂ , Cp ^* ₂ TiCl ₂ , Cp ^*
₂ ZrCl ₂ , Cp ^* ₂ HfCl ₂ , Cp ^* ₂ TiB
r ₂ , Cp ^* ₂ ZrBr ₂ , Cp ^* ₂ HfBr ₂ , Cp
^* ₂ TiI ₂ , Cp ^* ₂ ZrI ₂ , Cp ^* ₂ HfI ₂ ,
Cp ^* CpTiCl ₂ , Cp ^* CpZrCl ₂ , C
p ^* CpHfCl ₂ , Cp ^* CpTiBr ₂ , Cp ^* C
pZrBr ₂ , Cp ^* CpHfBr ₂ , Cp ^* CpTi
I ₂ , Cp ^* CpZrI ₂ , Cp ^* CpHfI
₂ (where Cp ^* is

[0010]

[Chemical 1] Indicates. ), And the following formula:

[0011]

[Chemical 2]

[Chemical 3] Etc. Here, as the atom for covalently bonding the two cyclopentadienyl groups of the metallocene dihalide used as the first component, for example, C, S
Examples thereof include i, O, N, Ge and the like. These first components are preferably synthesized separately and purified, but it is also possible to prepare raw materials for producing these components by adding them to the reaction system. Further, these components may be supported on a carrier before use.

The first component used in the present invention is G.I. Synthesized from cyclopentadienyl Grignard reagent and corresponding metal halides by Wilkinson et al. (J. Am. Chem. S.
oc. , 76, 4281-4284, 1954). Moreover, a commercial item can also be utilized.

The metal used as the second component is Li,
Alkali metal of Na, K, Rb, Cs, Fr, Be, M
Examples thereof include alkaline earth metals such as g, Ca, Sr, Ba, and Ra, alloys of two or more of these, or amalgams of one or more of these and mercury.

The catalyst of the present invention is one of organosilicon monomers having at least one hydrosilyl group, such as hydrosilane, dihydrosilane, trihydrosilane, or an organosilicon compound monomer having a hydrosilyl group, dihydrosilyl group, or trihydrosilyl group. The above is used for dehydrogenative condensation to produce an organosilicon polymer.

As the above-mentioned organosilicon compound monomer,
For example, the following compounds may be mentioned. MeSiH ₃ , Et
_{SiH 3, PhSiH 3, Me 3} SiSiH 3,

[0016]

[Chemical 4] ,as well as

[0017]

[Chemical 5] ,as well as

[0018]

[Chemical 6] , And _{H 3 Si-CH 2 -SiH 3} , H 3 Si-CH
_{(SiMe 3) -SiH 3, H} 3 Si-CH (Me) -
_{SiH 3, H 3 Si-CH} (Et) -SiH 3, H 3 S
i-CH (n-Pr) -SiH 3, H 3 Si-C (M
_{e) 2 -SiH 3, H 3} Si-CH (i-Pr) -Si
_{H 3, H 3 Si-C} (Me) (Et) -SiH 3, H 3
Si-C (Me) (SiMe 3) -SiH 3, H 3 Si
_{-C (Et) (SiMe 3)} -SiH 3, H 3 Si-C
_{(SiMe 3) 2 -SiH 3,} H 3 Si-CH 2 CH
_{(Me) -SiH 3, H 3} Si-CH 2 CH (Et) -
_{SiH 3, H 3 Si-CH} 2 C (Me) 2 -SiH 3,
_{H 3 Si-CH (Me)} CH (Me) -SiH 3, H 3
_{Si-CH 2 CH (SiMe 3} ) -SiH 3, H 3 Si
_{-CH 2 C (Me) (SiMe} 3) -SiH 3, H 3 S
_{i-CH 2 C (SiMe 3} ) 2 -SiH 3, H 3 Si-
_{CH (Me) CH (SiMe 3} ) -SiH 3, H 3 Si
_{-CH (SiMe 3) CH (SiMe} 3) -SiH 3,
_{H 3 Si- (CH 2) 3} -SiH 3, H 3 Si- (CH
₂ ) ₂ CH (Me) -SiH ₃ , H ₃ Si-CH (Si
_{Me 3) CH 2 CH 2 -SiH} 3, H 3 Si-CH 2 C
_{H (SiMe 3) CH 2 -SiH} 3, H 3 Si-CH =
_{CHCH 2 -SiH 3, H 3 Si-} (CH 2) 4 -Si
_{H 3, H 3 Si-CH} = CHCH = CH-SiH 3, H
_{3 Si-CH 2 CH = CHCH} 2 -SiH 3,

[0019]

[Chemical 7] And

[0020]

[Chemical 8] The dehydrogenative condensation reaction carried out using the catalyst of the present invention may be carried out in an open system or a closed system. The reaction may be carried out in a liquid phase or without a solvent, but is preferably a hydrocarbon solvent such as hexane, benzene or toluene, and / or tetrahydrofuran (TH
F), in the presence of a solvent such as ether. As an example of preferable reaction conditions, preferably 1.0 × 10 ^{−7 to} 100 mol%, particularly preferably 1.0 × 10 ⁻⁴ to 10 mol% of the formula Cp ₂ M of the first component with respect to the organosilicon monomer.
The metallocene dihalide represented by X ₂ , and preferably 1.0 × 10 ⁻¹⁰ to 10 ⁵ mol% relative to the first component,
Particularly preferably, the above catalyst comprising 1.0 × 10 ⁻⁷ to 10 ⁴ mol% of the second component metal is used, and the reaction system is hydrogen, nitrogen,
Place in a non-oxidizing gas atmosphere such as argon or helium,
The reaction temperature is about −60 to 300 ° C., more preferably about 20 to 180 °
C. and the reaction time is about 5 minutes to 10 days, more preferably about 10 minutes to 48 hours. The repeating unit, molecular weight, dehydrogenation rate, and degree of crosslinking of the polymer can be changed by changing the temperature, reaction time, catalyst, etc. during the reaction.
For example, when the reaction temperature is low and the reaction time is short, the molecular weight is low, and conversely, when the reaction temperature is high and the reaction time is long, the molecular weight is high.

Although the present invention is not limited by a particular theory, the reason why the catalyst of the present invention exerts its effect is that the metallocene dihalide as the first component, the metal as the second component, and the reacting organosilicon monomer. It is considered that the above three are involved in each other to proceed the reaction, and at this time, the metal as the second component acts as a reducing agent to reduce the metallocene dihalide and generate a reactive species.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0023]

【Example】

[0024]

Example 1 5.0 g of phenylsilane as a monomer
(46 mmol), toluene 5 ml, Cp ₂ TiCl ₂
87 mg (0.33 mmol, 0.7 for monomer)
2 mol%), lithium metal 4.8 mg (0.70 mmol), needle valve, magnetic stirrer capacity 100
In addition to a pressure resistant reactor of ml, freeze deaeration was performed twice, and the tube was sealed under a nitrogen atmosphere. This was heated in an oil bath at 80 ° C. for 5 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 4.3 g of organosilicon polymer was obtained (yield 86%). The molecular weight by GPC analysis is M _n (number average molecular weight) 630 in terms of polystyrene,
It was _Mw (weight average molecular weight) 810. When the ¹ H-NMR spectrum of this organosilicon polymer was measured (the spectrum is shown in FIG. 1), 4.2 to 5.2 pp.
The peak due to hydrogen bonded to the silicon atom at m is
Peaks attributable to the protons of the phenyl group were observed at 6.5 to 8.0 ppm (the peak of the methyl group of the residual solvent toluene was observed at 2.1 ppm). Further, when an IR spectrum of this organosilicon polymer was measured (the spectrum is shown in FIG. 2), a peak due to Si—H and Si—H ₂ was found at around 2107 cm ⁻¹ , which was 910c.
Peaks based on Si—H ₂ were observed around m ⁻¹ .

[0025]

Example 2 n-hexylsilane as a monomer 5.
3 g (46 mmol), benzene 5 ml, Cp ₂ ZrC
l ₂ 96 mg (0.33 mmol, 0.72 mol% relative to the monomer), lithium metal 4.8 mg (0.70
Was added to a pressure resistant reactor with a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, and freeze deaeration was performed twice, and the tube was sealed under a nitrogen atmosphere. This was heated in an oil bath at 80 ° C. for 5 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 4.6 g of organosilicon polymer was obtained (yield 87%). The molecular weight by GPC analysis is polystyrene-converted M _n 650, M _w 830
Met.

[0026]

Example 3 4.8 g (46 mmol) of 1,1,1-trimethyldisilane as a monomer, 5 ml of benzene,
Cp ₂ HfCl ₂ 125 mg (0.33 mmol, 0.72 mol% with respect to monomer), metallic lithium 4.8 m
g (0.70 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice and then sealed under a nitrogen atmosphere. 80 ° C
The mixture was heated for 5 hours in the oil bath described above, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure.
4.1 g of organosilicon polymer was obtained (yield 85%).
The molecular weight by GPC analysis is M _n 34 in terms of polystyrene.
00 and _Mw 13800.

[0027]

Example 4 p-Tolylsilane as a monomer 5.6
g (46 mmol), hexane 5 ml, Cp ₂ ZrBr
₂ 126 mg (0.33 mmol, 0.72 mol% relative to monomer), lithium metal 4.8 mg (0.70
Was added to a pressure resistant reactor with a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, and freeze deaeration was performed twice, and the tube was sealed under a nitrogen atmosphere. This was heated in an oil bath at 50 ° C. for 5 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 4.6 g of organosilicon polymer was obtained (yield 82%). The molecular weight by GPC analysis is polystyrene converted into M _n 780 and M _w 850.
Met.

[0028]

Example 5 Cyclohexylsilane 5.2 g (46 mmol) as a monomer, THF 5 ml, Cp ₂ Zr
I ₂ 157 mg (0.33 mmol, 0.72 mol% based on the monomer), calcium metal 28.0 mg (0.02 mol%).
70 mmol) was added to a pressure resistant reactor with a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, and freeze deaeration was performed twice, and the tube was sealed under a nitrogen atmosphere. This was heated in an oil bath at 110 ° C. for 8 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 4.5 g
To obtain an organosilicon polymer (yield 87%). The molecular weight by GPC analysis is polystyrene-converted M _n 320, M _w
It was 570.

[0029]

Example 6 2-silylbutane 4.0 as a monomer
g (46 mmol), CpCp ^* ZrCl ₂ 119 mg
(0.33 mmol, 0.72 mol% with respect to monomer), metallic sodium 16.0 mg (0.70 mmol), needle valve, 100 equipped with magnetic stirrer
In addition to a pressure resistant reactor of ml, freeze deaeration was performed twice, and the tube was sealed under a nitrogen atmosphere. This was heated in an oil bath at 80 ° C. for 3 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 3.6 g of organosilicon polymer was obtained (yield 90%). The molecular weights by GPC analysis were M _n 640 and M _w 830 in terms of polystyrene.

[0030]

Example 7 Phenylmethylsilane as a monomer 5.6 g (46 mmol), Cp ₂ ZrCl ₂ 96 mg
(0.33 mmol, 0.72 mol% relative to monomer), sodium-potassium alloy 22.0 mg (0.7
(0 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice, and then sealed under a nitrogen atmosphere. This was heated in an oil bath at 150 ° C. for 15 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 4.6 g
The organosilicon polymer of was obtained (yield 82%). The molecular weight by GPC analysis is polystyrene-converted M _n 330, M _w
It was 610.

[0031]

Example 8 6.1 g (46 mmol) of 2-trimethylsilylethylsilane as a monomer, Cp ₂ ZrCl
₂ 96 mg (0.33 mmol, 0.
72 mol%), sodium-mercury amalgam 5.0 g
(Sodium 16.0 mg, 0.70 mmol mercury 5.0 g, 25 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, and freeze deaeration was performed twice, followed by nitrogen. The tube was sealed under an atmosphere. This was heated in an oil bath at 80 ° C. for 5 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 5.1 g of organosilicon polymer was obtained (yield 84
%). The molecular weight by GPC analysis is M in terms of polystyrene.
_n 790 and M _w 890.

[0032]

Example 9 5.5 g (46 mmol) of 2,2-dimethyltrisilane as a monomer, 5 ml of toluene, Cp
₂ ZrCl ₂ 96 mg (0.33 mmol, 0.72 mol% based on monomer), metallic sodium 16.0 mg
(0.70 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice, and then sealed under a nitrogen atmosphere. This was heated in an oil bath at 80 ° C. for 8 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure.
4.9 g of organosilicon polymer was obtained (yield 89%).
The molecular weight by GPC analysis is M _n 25 in terms of polystyrene.
60, _Mw 13800.

[0033]

Example 10: Disilylethane 4.1 as a monomer
g (46 mmol), toluene 5 ml, Cp ₂ ZrCl
₂ 96 mg (0.33 mmol, 0.
72 mol%), 27.4 mg (0.70 mmol) of potassium metal, needle valve, capacity 1 equipped with a magnetic stirrer
In addition to a 00 ml pressure resistant reactor, freeze deaeration was performed twice, and the tube was sealed under a nitrogen atmosphere. This was heated in an oil bath at 60 ° C. for 5 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure. 3.7 g of organosilicon polymer was obtained (yield 90%). The molecular weight by GPC analysis is polystyrene conversion M _n 4200, M _w 198
It was 00.

[0034]

Example 11 2.1 g (23 mmol) of 1,2-dimethyldisilane as a monomer, 2.4 g (23 mmol) of 1,1,2-trimethyldisilane, and 5 m of toluene.
l, Cp ₂ ZrCl ₂ 96 mg (0.33 mmol, 0.72 mol% relative to monomer), metal beryllium 7.
3 mg (0.70 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice, and then sealed under a nitrogen atmosphere. This one
After heating in an oil bath at 20 ° C. for 10 hours and passing through a Florisil column (toluene solvent) to remove the catalyst, the solvent was distilled off under reduced pressure. 3.6 g of organosilicon polymer was obtained (yield 80
%). The molecular weight by GPC analysis is M in terms of polystyrene.
_n 3010 and _Mw 9960.

[0035]

Example 12 6.3 g (46 mmol) of 1,4-disilylbenzene as a monomer, 5 ml of toluene, Cp
₂ ZrCl ₂ 96 mg (0.33 mmol, 0.72 mol% based on the monomer), metallic magnesium 17.0 m
g (0.70 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice and then sealed under a nitrogen atmosphere. 70 ℃
The mixture was heated in the oil bath for 6 hours, passed through a Florisil column (toluene solvent) to remove the catalyst, and then the solvent was distilled off under reduced pressure.
5.9 g of organosilicon polymer was obtained (94% yield).
The molecular weight by GPC analysis is M _n 28 in terms of polystyrene.
00 and _Mw 15520.

[0036]

Comparative Example 1 5.0 g of phenylsilane as a monomer
(46 mmol), benzene 5 ml, Cp ₂ ZrCl ₂
96 mg (0.33 mmol, 0.7 for monomer)
(2 mol%) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice, and then sealed under a nitrogen atmosphere. 1 in an oil bath at 150 ° C
Heated for 5 hours. No polymer was obtained and the phenylsilane monomer was recovered.

[0037]

[Comparative Example 2] 5.0 g of phenylsilane as a monomer
(46 mmol), benzene 5 ml, metallic lithium 4.
8 mg (0.70 mmol) was added to a pressure resistant reactor having a capacity of 100 ml equipped with a needle valve and a magnetic stirrer, freeze-deaerated twice and then sealed under a nitrogen atmosphere. This one
Heat in an oil bath at 50 ° C. for 15 hours. No polymer was obtained,
The monomer phenylsilane was recovered.

[0038]

Industrial Applicability As described above, the present invention can provide a highly active dehydrogenative condensation catalyst which is easy to synthesize and easy to handle. Further, the organosilicon polymer can be efficiently produced from the organosilicon monomer in a short time.

[Brief description of drawings]

¹ H of the organosilicon polymer obtained in Example 1
-NMR spectrum chart.

FIG. 2 IR of the organosilicon polymer obtained in Example 1.
Spectrum chart.

Claims (1)

[Claims] 1. A first component of the formula Cp ₂ MX ₂ (wherein Cp is independently substituted or unsubstituted η ^5-
A cyclopentadienyl group is shown, and two cyclopentadienyl groups may be covalently bonded to each other via one or more atoms. M is Ti, Zr, Hf, X is F, C
l, Br and I are shown. ), And an alkali metal, an alkaline earth metal or an alloy of two or more of these as a second component, or an amalgam of one or more of these and mercury, for dehydrogenative condensation of an organosilicon monomer catalyst.