JPH09104689A - Dihydroxysilane having cyclic ether group - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound, useful for providing a hydrophilic silicone polymer and applicable to an antifouling sealant, etc., for building. SOLUTION: This dihydroxysilane is represented by formula I. The compound is obtained by initially reacting methyldichlorosilane with a compound represented by the formula R<1> OH and/or R<2> OH (R<1> and R<2> are each a 1-6C alkyl), providing a methyldialkoxysilane represented by formula II, then carrying out the addition reaction of SiH group in the resultant compound with CH=CH2 group in a 2-allyloxymethyl-1,4-dioxane in the presence of an addition reactional catalyst such as a platinum-based catalyst, preferably without a solvent, affording a new [3- (1,4-dioxan-2-yl)methoxy}propyl]methyldialkoxysilane represented by formula III and finally hydrolyzing the prepared compound represented by formula III with preferably a cation exchange resin as a catalyst for hydrolysis. The hydrolytic reaction is carried out preferably at -30 to +80 deg.C usually for 1-60min.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a dihydroxysilane having a cyclic ether group, which is useful as a raw material for hydrophilic silicone oil, varnish, rubber and the like.

[0002]

2. Description of the Related Art
In the molecule, hydrophilic silicone with ether group
On ≡SiCH_TwoCH_TwoCH_TwoO (C_TwoH_FourO) _a(C_ThreeH₆O)
_bR (however, R = H, -CH_Three, -C_FourH₉Or -COCH
_Three, A, b = an integer of 1 to 1000)
Known foam stabilizers with an ether group.
Is used as (Reference: Kunio Ito, "Silicone"
Handbook ", Nikkan Kogyo Shimbun, 179 pages, 199.
0 years) is a cyclic ether group, especially 1,4-dioxanyl
Organosilicon compounds having groups have not been reported.

[0003]

Means for Solving the Problems and Embodiments of the Invention In view of the need for hydrophilic silicone oils, silicone varnishes and silicone rubbers in the art, the present inventors have proposed hydrophilic silicones. As a result of diligent research on a novel organosilicon compound that gives a compound, SiH of methyldialkoxysilane of the following general formula (3) obtained from methyldichlorosilane of the following formula (2)
Group and 2-allyloxymethyl-represented by the following formula (4)
1,4-dioxane -CH = CH ₂ group and a platinum-based, by addition reaction in the presence of an addition reaction catalyst rhodium or the like, a novel organosilicon compound represented by the following general formula (5), i.e. [3-{(1,4-dioxan-2-yl) methoxy} propyl] methyl dialkoxysilane is usually obtained in a high yield of 85% or more, and the organosilicon compound (5) is hydrolyzed. Have found that a novel dihydroxysilane represented by the following formula (1) can be obtained.

[0004]

Embedded image (However, in the formula, R ¹ and R ² are the same or different from each other and have 1 carbon atoms.
To 6 alkyl groups. )

The dihydroxysilane represented by the formula (1) has two OH groups capable of condensing in the molecule and is easily polymerized in the presence of an acid or an alkali catalyst to give a cyclic ether group. It was found that the polysiloxane has a hydrophilicity, and the contact angle of water on the film formed on the glass substrate is 55 ° at a film thickness of 500Å, indicating that the polysiloxane has good hydrophilicity. It has been found to be useful in the production of polysiloxanes.

Further, conventionally, a so-called Rocho in which metallic silicon and methyl chloride are catalytically reacted at a high temperature using a copper catalyst
w direct method (reference; EG Rochow, J. Am.
Soc. , 67, 963, 1945), 0.5 to 3% of the total amount of chlorosilane obtained is methyldichlorosilane of the above formula (1), and effective use of this byproduct dichlorosilane is strongly desired. However, since the dihydroxysilane of the formula (1) of the present invention can use the dichlorosilane by-produced from this direct method as a raw material, it is industrially important from the viewpoint of effective use of this by-produced dichlorosilane. The present inventors have found out that they exist and have completed the present invention.

The present invention will be described in more detail below. The cyclic ether group-containing dihydroxysilane of the present invention is represented by the following formula (1).

[0008]

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The dihydroxysilane of the formula (1) can be synthesized by hydrolyzing a dialkoxysilane represented by the following general formula (5) as shown in the following reaction formula.

[0010]

Embedded image (However, in the formula, R ¹ and R ² are each an alkyl group having 1 to 6 carbon atoms.)

Here, when the dialkoxysilane of the formula (5) is hydrolyzed, a catalyst for hydrolysis is required. As the catalyst, hydrochloric acid, phosphoric acid, sulfuric acid, methanesulfonic acid,
An acidic catalyst such as trifluoromethanesulfonic acid, trifluoroacetic acid or a cation exchange resin, or a base catalyst such as caustic soda, caustic potash, triethylamine or ammonia can be used. However, as the catalyst for condensing the product dihydroxysilane and not polymerizing it, the cation exchange resin is most preferable among them. When a cation exchange resin is used, the solid cation exchange resin can be completely removed by filtration, and post-treatment such as neutralization is not particularly necessary.

The amount of water used for hydrolysis is 1 equivalent or more, preferably 1.05 to 20 equivalents, based on the alkoxy group of the dialkoxysilane (5) as a raw material. When the amount is less than 1 equivalent, the amount of residual alkoxy groups increases, which is not preferable. The water used is preferably distilled water or ion-exchanged water.

The hydrolysis reaction is usually carried out under normal pressure, but in some cases it may be carried out under pressure. If necessary, the reaction operation can be carried out while distilling off the alcohol by-produced from the reaction under reduced pressure conditions. The reaction temperature is usually -50 ° C to 100 ° C, particularly -3.
0 ° C to 80 ° C is preferred. When the reaction temperature is higher than 100 ° C., the condensation reaction between the produced SiOHs progresses to form a dimer or higher polysiloxane, and as a result, the yield of the target product decreases. On the other hand, if the temperature is lower than -50 ° C, the reaction rate is slow, which is not preferable. The reaction time is usually 1 to 60 minutes.

After completion of the reaction, the objective dihydroxysilane can be obtained by stripping alcohol by-produced by the reaction and water used in excess.

Here, the dialkoxysilane of the above formula (5) is a novel substance, and this dialkoxysilane (5)
Is a methyldialkoxysilane represented by the following general formula (3) as a starting material according to the following reaction formula, and 2-allyloxymethyl-1,4-dioxane of the formula (4) is used as an addition reaction catalyst. , Preferably 85% by carrying out the addition reaction in the presence of a platinum-based or rhodium-based catalyst.
It can be synthesized with the above high yield. Note that expression (3)
The methyldialkoxysilane is obtained by a known method, in particular by reacting the above-mentioned methyldichlorosilane of the formula (2) with an alcohol. In this case, the methyldichlorosilane may be methyldichlorosilane obtained by the direct method described above. Can be used.

[0016]

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In the above reaction, methyldialkoxysilane of formula (3) and 2-allyloxymethyl- of formula (4)
The reaction molar ratio with 1,4-dioxane is usually 1: 1 to 10
However, the molar ratio considering economic efficiency is preferably 1
Pairs 1-2.

The addition reaction catalyst used in this reaction is
Platinum-based catalysts and rhodium-based catalysts are preferable, but platinum-based catalysts that can be used include elemental platinum, chloroplatinic acid, alcohol treated chloroplatinic acid, platinum cyclopropane complex, platinum ethylene complex and the like. On the other hand, rhodium-based catalysts that can be used are rhodium chloride, a triphenylphosphorus complex of rhodium chloride, or a complex of tetrabutylammonium hydride and rhodium chloride. The amount of the catalyst used is 1 to 10,000 of the weight of the methyldialkoxysilane used.
ppm, but a suitable amount is 10 to 1,000 ppm.

In this reaction, aromatic solvents such as toluene and xylene, aliphatic solvents such as n-heptane and n-hexane, tetrahydrofuran, dioxane,
Although it may be carried out in the presence of an ether solvent such as diethyl ether, it is preferably carried out without a solvent because the pot yield (kettle yield) is reduced.

The reaction is usually carried out under normal pressure, but it may be carried out under pressure. The reaction temperature is usually 10 to 200 ° C, but a suitable range is 20 to 150 ° C. Usual reaction time is 0.5 to 10 hours, but a suitable range is 2 to 6 hours.

Here, the 2-allyloxymethyl-1,4-dioxane of the formula (4) can be obtained by a conventionally known method. In particular, ethylene chlorohydrin and allyl glycidyl ether are treated with a stannic chloride catalyst. In the method for producing 2-allyloxymethyl-1,4-dioxane by causing an intramolecular cyclization reaction by using a dehydrochlorinating agent after contacting and reacting in the presence of It is preferable to coexist a silicon compound having at least one SiO bond in the molecule during the reaction between phosphorus and allyl glycidyl ether and the above intramolecular cyclization reaction,
As a result, it is possible to suppress the production of a by-product polymer and obtain 2-allyloxymethyl-1,4-dioxane in a high yield.

[0022]

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The dihydroxysilane of the formula (1) of the present invention is easily polymerized in the presence of an acid or alkali catalyst to form a polysiloxane having a structure represented by the following formula (a). This polysiloxane (a) has a contact angle to water of 55 ° when a 500 Å film is formed on a glass substrate, which means that n = 7 or more of-[Si (CH ₃ ) ₂ ] _n-. The contact angle of water of the 495Å film of polysiloxane having the structure of 98 is
It exhibits excellent hydrophilicity as compared with the case of being °.

[0024]

Embedded image (N = 7 or more)

Therefore, the dihydroxysilane of the present invention is
Used as the basic raw material for various silicone products,
In particular, by further inducing into siloxane polymer, it becomes a processed product characterized by hydrophilicity, such as cosmetic oil, textile softening agent, hydrous contact lens, foam stabilizer for polyurethane, antifog agent, ion conductive material, paintable surface paint. Applied as hydrophilic rubber, stain resistant sealant.

[0026]

INDUSTRIAL APPLICABILITY The dihydroxysilane having a cyclic ether group of the present invention is useful for obtaining a hydrophilic silicone polymer, and can be applied to a stain resistant sealant for construction and the like.

[0027]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

Example 1 100.0 g of [3-{(1,4-dioxan-2-yl) methoxy} propyl] methyldimethoxysilane represented by the following formula (i) was added to a 500 ml flask purged with nitrogen. 0.378 mol) and 50 g of distilled water (2.775 mol) were charged. To this mixture was added 0.5 g of a cation exchange resin (trade name: CT-175, manufactured by Purolite).

[0029]

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When the reaction was carried out with stirring at 25 ° C., the reaction system became homogeneous after 3 minutes, indicating that the reaction had proceeded. Further, while maintaining the internal temperature at 25 to 30 ° C., stirring was continued for 10 minutes while removing methanol by-produced during the reaction under reduced pressure.
After removing the solid ion-exchange resin by filtration, the by-product methanol and excess water were removed under reduced pressure to obtain a colorless and transparent oily product (yield 79.4).
g (0.336 mol), yield 88.9%).

Elemental analysis of the oil obtained, ¹ H-NMR
The results of the analysis and IR analysis are shown below, and this oily substance is [3-{(1,4-dioxan-2-yl) methoxy} propyl] methyldimethoxysilane represented by the following formula (ii). Was identified.

[0032]

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[0033]

Embedded image IR analysis An IR chart is shown in FIG.

Example 2 In Example 1, the dialkoxysilane was replaced with [3-{(1,4-dioxan-2-yl) methoxy} propyl] methyldimethoxysilane of the above formula (i), and When the reaction was carried out under the same conditions except that diethoxysilane of formula (iii) was used,
The yield of the objective dihydroxysilane of the above formula (ii) is 8
Obtained in 6.4%.

[0035]

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Example 3 In Example 1, the dialkoxysilane was replaced by [3-{(1,4-dioxan-2-yl) methoxy} propyl] methyldimethoxysilane of the above formula (i), and When the reaction was carried out under the same conditions except that the dihexoxysilane of formula (iv) was used,
The yield of the objective dihydroxysilane of the above formula (ii) is 8
Obtained at 1.1%.

[0037]

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Reference Example 1 250.0 g (2.354 mol) of methyldimethoxysilane and chloroplatinic acid hexahydrate were placed in a 1000 ml round bottom flask equipped with a stirrer, a thermometer, a reflux condenser and a dropping funnel. .0041g was added and stirred.
To this mixture, 372.5 g (2.355 mol) of 2-allyloxymethyl-1,4-dioxane was added dropwise at 30 ° C. over 3 hours. After the dropping was completed, stirring was continued at 35 ° C. for 2 hours. After the reaction was completed, the product was distilled under reduced pressure to obtain 550.3 g of a colorless transparent liquid material (yield 88.4).
%).

The measurement results of boiling point, refractive index, viscosity, GC-MS spectrum, ¹ H-NMR and infrared absorption spectrum of the obtained liquid product are as follows. That is, [3-{(1,4-
Dioxan-2-yl) methoxy} propyl] methyldimethoxysilane. Boiling point: 125 ° C./4 mmHg Refractive index (n ²⁵ _D ): 1.4414 Viscosity (cs, 25 ° C.): 6.5 GC-MS analysis: (m / e) M ⁺ 264

[0040]

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Reference Example 2 200.0 g (1.490 mol) of methyldiethoxysilane and chloroplatinic acid hexahydrate were placed in a 1000 ml round bottom flask equipped with a stirrer, a thermometer, a reflux condenser and a dropping funnel. 0.0041 g was added and stirred.
2-Aryloxy-1,4-dioxane 2 was added to this mixture.
36.0 g (1.492 mol) was added dropwise at 35 ° C. over 2.5 hours. After the dropping was completed, stirring was continued at 40 ° C. for 2 hours. After the reaction was completed, distillation was performed under reduced pressure to obtain 371.8 g of a colorless transparent liquid material (yield 85.3).
%).

The measurement results of the boiling point, refractive index, viscosity, GC-MS spectrum, ¹ H-NMR and infrared absorption spectrum of the obtained liquid are as follows. That is, [3-{(1,4-
Dioxan-2-yl) methoxy} propyl] methyldiethoxysilane. Boiling point: 139 ° C / 4 mmHg Refractive index (n ²⁵ _D ): 1.4390 Viscosity (cs, 25 ° C): 5.8 GC-MS analysis: (m / e) M ⁺ 292

[0043]

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Reference Example 3 In Reference Example 1, H (CH ₃ ) Si (OCH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ C is used in place of methyldimethoxysilane of the SiH group-containing dialkoxysilane.
When the reaction was carried out under the same conditions except that 513.5 g (2.354 mol) of H ₃ ) ₂ was used, the target compound of the following formula was obtained in a yield of 88.1%.

[0045]

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[Brief description of the drawings]

FIG. 1 is an infrared absorption spectrum of the target compound of Example 1.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Masaharu Takahashi 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Technology Laboratory

Claims (1)

[Claims] 1. A dihydroxysilane having a cyclic ether group represented by the following formula (1). Embedded image