JPS60188391A - Production of organosilane - Google Patents

Abstract

PURPOSE:To produce the titled compound having low residual Cl-content and suitable as a hardener for a cold-curing silicone rubber useful as a sealant for nuclear power plant, in high yield, by contacting an organosilane having a specific structure with an alcohol in the presence of a catalyst. CONSTITUTION:The objective compound of formula II (b is 1, 2 or 3; a+b<=3) having alkenyloxy group and alkoxy group can be produced by contacting (A) the organosilane of formula I (R<1> is H, alkyl, alkenyl, etc.; R<2>-R<4> are H or same group as R<1>; a is 0, 1 or 2) [e.g. methyltri(isopropenyloxy)silane, etc.] as a starting material with (B) the alcohol of formula R<5>OH (R<5> is alkyl, alkenyl, etc.) (e.g. methanol) in the presence of (C) a catalyst (preferably triethylamine).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing organosilanes, particularly organosilanes containing alkenyloxy and alkoxy groups in the molecule.

Organosilanes containing alkenyloxy and alkoxy groups directly bonded to silicon atoms in their molecules are said to be useful as curing agents for room-temperature curable silicone rubber; A partial alkoxysilane is synthesized by reacting an organochlorosilane containing a bonded chlorine atom with an alcohol, and then a ketone compound is added to the remaining chlorine atom in the presence of a transition metal compound catalyst and a hydrogen chloride scavenger. It is produced by a method of reaction to form the corresponding organosilane.

However, this method has the disadvantage that it is difficult to separate and purify the target product due to the large number of by-products, and the reaction yield is low.1)
In addition, since the starting material is organochlorosilane, it is not possible to reduce the residual chloro acid in the target product only by distillation separation, and it is necessary to reduce the residual chloro acid to 200 ppm or less, especially 20 ppm P1.
This has the disadvantage that the industrial use of room-temperature-curable silicone rubber to which it is added is severely restricted.

The present invention relates to a method for producing an organosilane containing an alkenyloxy group and an alkoxy group that overcomes these disadvantages.11. This is a general formula hydrogen atom or an unsubstituted or substituted alkyl group.

Alkenyl group or aryl group -R2, R3-R4 are hydrogen atoms or the same group as R1, a is an integer of O to 2) Organosilane represented by the general formula R'OH\, R5 is unsubstituted or substituted Alkyl group, alkenyl group, aryl group or formula -0CR, CH20R'(R' is the above R
The same as above, b is an integer from 1 to 3, and a+≦3) is reacted with an alcohol represented by the group represented by the formula %) in the presence of a catalyst. This method is characterized by obtaining an organosilane containing an alkenyloxy group and an alkoxy group.

In other words, the present inventors conducted various studies on efficient production methods for organosilanes containing alkenyloxy groups and alkoxy groups, and found that when the organosilane represented by the above general formula is reacted with an alcohol, the product can be produced in one step. In addition to discovering that it is possible to obtain an organosilane that is now obsolete, the organosilane obtained by this method can be obtained by significantly reducing the amount of residual chlorine. The present invention was completed after confirming that the citron products can be advantageously used as precision industrial materials.

Organosilane RI S used as an initiator in the method of the present invention
i (0-0=O-R4) a , 4-a - R1 is a hydrogen atom or a methyl group.

Ethyl group - Alkyl group such as propyl group, butyl group, alkenyl group such as vinyl group, allyl group, aryl group such as phenol group, or some or all of the hydrogen atoms bonded to the carbon atoms of these groups are replaced by halogen atom, Chloromethyl group, 3,3.3-)lifluoropropyl group substituted with cyan group, etc.

An unsubstituted or substituted monovalent hydrocarbon group composed of a cyanomethyl group, etc., in which u2, R1, and R4 are hydrogen atoms or the same monovalent hydrocarbon as R1 above, and -a is an integer from 0 to 2. This includes OH30H3 Si (00=OH2), H81 (OO=OH2), -
0H3Si(OO=OH2)3+ O□H,S i (
00=OH2),.

0H2=OH8i (00=OH2)3.06E5Si(
00=OH2), .

H81(OO=0)]2)2-on2=cHsi(o
Examples include a-aH2)2-. Note that since this organosilane is generally synthesized from organchlorosilane, it contains 10 ONl, 000 ppm of residual chlor I, but if it is used as it is as a starting material for the method of the present invention, it will not react with the target organosilane. Since the silane has a large amount of residual chlorine, wash it with water.

It is preferable to refine it by distillation or the like so that the amount of residual chlorine is 1 to 20 ppm.

Next, the alcohol to be reacted with this organosilane is represented by the general formula R'OH as described above.

This R5 is an unsubstituted or substituted alkyl group, alkenyl group, aryl group, or has the formula -O0H20H,O
R is the same unsubstituted or substituted alkyl group as R as described above.

Although it is considered to be an alkenyl group or an aryl group, -
This includes OHOH, O□H, OH-0, H70E(,0
Direct complex alcohols such as 4H90H.

Branched alcohols such as (OH3)20HOH, (OR,)300H + 0H300H20H20H.

Cellosolve type products such as 02H500H20H20H are exemplified. The amount of this alcohol compound mixed with the organosilane is preferably 80 to 120 moles of the theoretical amount required for partial alkoxylation of the organosilane. It may be determined by considering the boiling point difference between the organosilane and the reaction by-product.

The reaction between organosilane and alcohol described above must be carried out in the presence of a catalyst, and this catalyst
Known catalysts such as acidic catalysts such as toluenesulfonic acid and basic catalysts containing anno group such as silicon compounds containing triethylamino-diethyl hydroxya-guanidyl groups may be used, but they are industrially inexpensive. It is preferable to use triethylamine, which is easily available and easily separated during distillation, and is generally added in an amount of 0.01 to 5% by weight based on the organosilane as a starting material.

In the method of the present invention, a catalyst may be added to the organosilane as the starting material, and the above-mentioned alcohol may be added dropwise to the catalyst to cause the reaction. The reaction may be carried out in the presence of a solvent inert to the reaction.

The method of the present invention is to obtain an organosilane having an alkenyloxy group and an alkoxy group through a one-step reaction between an organosilane represented by the above general formula and an alcohol. Since organosilane with a significantly reduced residual chlorine content can be obtained, room-temperature-curing silicone rubber using this curing agent is suitable for nuclear power generation applications where contamination with impurities such as chlorine atoms is extremely difficult. It has the advantage of being useful as a sealing material, aerospace industry material, ultra-precision industrial material, and as a sealing material related to Electro-X.

Next, examples of the present invention will be given.

Example 1 The amount of chlorine remaining in a 11 separable flask equipped with a reflux condenser, thermometer, stirring bar and dropping funnel was 2201).
428 g (2
After adding 4y of triethylamine and heating to 35°C, add 12 mol of methanol from the dropping funnel while stirring.
8p (4 mol) was added dropwise over 1 hour, heated under reflux for 2 hours, and then distilled under reduced pressure, resulting in a boiling point of 74°C/]
] 188g of 411jIlHy was obtained.

Next, when we analyzed this, we found that this IR
is as shown in the vJJ diagram, and further NMR, Go
-MS results confirmed that this was methyl(impropenyloxyV)dimethoxysilane, and the amount of residual chlorine in this product was also 97 ppm, and the yield was 58%.

Example 2 In the same apparatus as in Example 1, 428 g (2 moles) of methyltri(isopropenyloxy)silane, which had been washed with water and distilled to reduce the amount of residual chlorine to 5 ppm, and 41 g of triethylamine were placed in the same apparatus as in Example 1. After heating to 35°C, 64 g (2 mol) of methanol was added to it from the dropping funnel while stirring.
When added dropwise for 0 minutes, heated to 55-60℃ for 1 hour, and then distilled under reduced pressure, the iJe point was 98℃/112
207g of TomoHg. was obtained.

Next, when this was examined by IR, NMR, and Go-MS, it was confirmed that this was methyldi(isopropenyloxy)methoxysilane, and the residual chloride content of this was 3p.
pm], and the yield was 53%.

Comparative Example: 64 g (2 moles) of methanol was added dropwise to 299.12 moles of methyltrichlorosilane over about 50 minutes, and the mixture was heated to 60°C for 1 hour.
After heating for a period of time, the mixture was distilled under reduced pressure to obtain methyldichloromethoxysilane 160II.

Next, add triethylamine 2909 to this. acetone 90
0 g and 5.0 g of cuprous chloride were added.

After reacting at 40°C for 24 hours, salts were removed by filtration and distillation under reduced pressure yielded 103g of a product with a boiling point of 99°C/110nrnH9.

As a result of analysis, it was confirmed that this material was the same methyldi(isopropenyloxy)methoxysilane as that obtained in Example 2, but the residual amount of chlorine was 260
ppm, and the yield was also 28.

Examples 3 to 8 Using the same method as in Example 1, organosilane as a starting material was prepared with a residual chloro content of 5 ppm, and methyltri(isopropenyloxy)silane with a residual chloro content of 7 ppm.
Synthesis of silane was carried out using vinyltri(isopropenyloxy)silane with m and alcohols such as methanol, ethanol, methyl cellosolve, and ethyl cellosolve, and the results shown in Table 1 below were obtained.

Note that the silane R obtained in Example 3.5.8 was as shown in FIGS. 2 to 4.

-4. Brief description of the drawings Figures 1 to 4 all show the IR of the organosilane obtained in this example, and Figure 1 shows the IR of the organosilane obtained in Example 1.
Figure 2 shows Example 3. FIG. 3 shows the IR of the organosilane obtained in Example 5, and FIG. 4 shows the IR of the organosilane obtained in Example 8.

16-

Claims (1)

[Claims] R1 is a hydrogen atom or an unsubstituted or substituted alkyl group, alkenyl group or aryl group. R", R", R' are hydrogen atoms or the same group as R1, a is an integer of O to 2),
General formula R'OB [where R1 is a non-1a substituted or substituted alkyl group, alkenyl group, aryl group or formula -00
820H,OR'(R' is the same as R1 above)] in the presence of a catalyst to form the general formula \R1, R2, R", R', R'
, a is the same as above. b is an integer from 1 to 3, a + b≦3. ) A method for producing an organosilane, which comprises obtaining an organosilane containing an alkenyloxy group and an alkoxy group. 2. The method for producing organosilane according to claim 1, wherein the medium is a basic catalyst. 3. Organosilane has the above general formula where R is a methyl group and R-
The method for producing organosilane according to claim 1, wherein R is a hydrogen atom.