JPS6172791A - Production of dialkoxydiphenylsilane - Google Patents

Abstract

PURPOSE:An alkoxycyclodiphenylsilane obtained from dichlorophenylsilane and a monohydric saturated alcohol is subjected to reaction with a solvent amount of a monohydric saturated alcohol at a specific temperature to enable high-yield production of the titled compound of high purity in a shortened reaction time. CONSTITUTION:An alkoxydiphenylsilane resulting from reaction of dichloro diphenylsilane with a monohydric saturated alcohol, preferably methanol such as chloromethoxydiphenylsilane is allowed to react with a monohydric saturated alcohol, preferably in an amount of 1.5-20 times the silane at -10-30 deg.C using the same alcohol as a reaction solvent for 5-60min. Then, the reaction mixture is stood until it separates into 2 layers and the objective compound is obtained from the lower phase, e.g., in more than 97% purity and more than 90% yield.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for producing sial; Alkoxychlorodiphenyl 7:/
, Flucoxychlorodiphenylsila 7 to 1.1.
s times -etv or more monohydric saturated alcohol to 110
The present invention relates to a method for producing dialkoxydiphenylsilane, which is patented in that the reaction is carried out in a temperature range of -30°C using the monohydric saturated alcohol as a reaction solvent.

The dialkoxydiphenylsilane obtained in the present invention is a compound useful as an intermediate for silicone fabrics.

(Prior Art) - A method for producing dialkoxydiphenylsilane from I-rollodiphenyl 7rane and a monovalent saturated 7/' alcohol is known. This reaction is an equilibrium reaction, and the rate-determining condition for the reaction is how to remove the by-product hydrogen chloride from the reaction system.

In the conventional production method, when dichlorodiphenylsilane and a monohydric saturated alcohol such as methanol are reacted in a hydrocarbon-based or halogenated hydrocarbon-based solvent, hydrogen chloride as a by-product is removed from the reaction system. Proposed methods include blowing a large amount of inert gas into the reaction system, adding a base to the reaction system as a hydrogen chloride scavenger, refluxing it together with the solvent, and reducing the pressure in the reaction system (
Co11ect, Cz@ch, Chem, Comn5u
n,, Volume 1976, Page 110, Encyclo
pedia of Chemical Technology
gy, 3rd Edition, Volume 20, No. 916
Page (1982)].

(Problem to be solved by the invention) However, these methods are difficult to solve in the reaction, especially in the second step.
The reaction time from alkoxychlorodiphenyl 7rane to dialkoxydiphenylsilane is long, it is difficult to isolate and purify because an inorganic salt is produced as a by-product, or the yield is reduced because a polymer is produced as a by-product. At present, there are still many problems to be solved, such as difficulties in isolation and purification.

(Means for Solving the Problems) The present inventors have solved these drawbacks that occur when producing dialkoxydiphenylsilane from dichlorodiphenyl 7rane and monohydric saturated alcohol (as a result of various studies, The monohydric saturated alcohol used as one of the raw materials in this reaction is a very good solvent as an absorbent for by-product hydrogen chloride, and the product dialkoxydiphenylsilane is insoluble in this hydrogen chloride-containing alcohol. By paying attention to this, the present invention was completed.

That is, in this reaction, dichlorodiphenylsilane and a monovalent saturated alcohol are reacted to form alkoxychlorodiphenyl 7rane (without using a hydrocarbon-based reaction solvent) as a first-stage reaction. Examples of alcohols include methanol, ethanol, propatool, butanol, amyl alcohol, hexyl alcohol, and alcohols with larger carbon numbers; however, the method of the present invention is particularly suitable for lower alcohols such as methanol, ethanol, and propatool. For example, in the case of methanol, according to the conventional method, methyl chloride is easily produced by the reaction of by-produced hydrogen chloride and methanol, and at this time, the by-produced water hydrates the chlorine atoms and methoxy groups of methoxychlorodiphenyl sila. While it decomposes and causes binding reactions, reducing the yield of the target product,
According to the method of the present invention, such side reactions are less likely to occur, so the method of the present invention is particularly suitable. This reaction proceeds easily with equimolar reaction, and removal of the by-product chloride water system from the reaction system is also easy.

Next, this alkoxychlorodiphenylsilane is reacted with a monohydric saturated alcohol to form dialkoxydiphenylsilane. As the monohydric saturated alcohol, the above-mentioned
The same alcohols as those used in the step reaction are exemplified, but methanol, ethanol or propazole are preferred, with methanol being particularly preferred for the same reason as above. The amount of monohydric saturated alcohol used at this time is
Theoretically, the equimolar amount may be sufficient, but since it acts as an absorbent for by-product hydrogen chloride and as a reaction solvent, it is usually 1.
It is used in an amount of about 5 to 20 times the mole, but is not limited thereto.

Hydrogen chloride produced as a by-product is absorbed by the monohydric saturated alcohol, so the equilibrium shifts to the production system and the reaction proceeds easily. The reaction temperature is preferably low, and the reaction is usually carried out at -10 to 30°C. When the reaction temperature is low, the equilibrium shifts to the production system. When the same temperature is reached, the generated dialkoxydiphenylsilane becomes alkoxy7diphenylcranol.

This reacts again with sial; xydiphenylsilane to produce a polymer by-product. The reaction temperature of this polymer by-product is 50°C.
It becomes more noticeable before and after, and increases rapidly when the boiling point of the alcohol used is exceeded.

The reaction is preferably carried out at as low a temperature as possible, since the by-product of the polymer causes a decrease in yield, complication of the isolation/VifA process, and a decrease in purity. Although the reaction time varies somewhat depending on the reaction temperature, the reaction is usually completed in 5 to 60 minutes.

After the reaction is completed, the mixture is left standing to separate into two layers, and the lower layer, dialkoxydiphenylsilane, is separated at a yield of 90% or more.

The fractionated dialkoxydiphenylsilane has a purity of 97% or more, and contains less than 1% of polymers, so it requires a purification process such as distillation, in particular, by distilling off the alcohol contained in it. Dialkoxydiphenylsilane of sufficient quality can be obtained without any waste. Note that loading platforms that require high-purity dialkoxydiphenylsilane can be easily loaded by purification means such as rectification.

Furthermore, the alcohol in the upper layer contains unreacted alkoxychlorodiphenylsilane/formed dialkoxydiphenylsilane and by-product chloride solution, but it can be used as is for the next reaction.

The reaction of alkoxychlorodiphenyl 7-rant alcohol can be carried out by mixing the alcohol and a predetermined amount of alkoxychlorodiphenylsilane at once, or by dividing a predetermined amount of alkoxychlorodiphenylsilane into several batches and reacting for 0 minutes. Methods such as a method of repeating the liquid, or a method of continuously performing reaction and liquid separation using a seed-type or pipe-type reactor that can maintain the necessary reaction time can be used.

(Effects of the Invention) By quickly removing hydrogen chloride produced as a by-product to the outside of the reaction mixture, the present invention can reduce the reaction time between alkoxychlorodiphenylsilane and monohydric saturated alcohol, which took a long time in the conventional method. In addition to shortening the time, it also prevents the production of polymer by-products and improves the yield. In addition, the isolation operation is easy and does not require purification such as distillation to 1% (both are methods for producing dialkoxydiphenylsilane with a high purity of 97% or more).

(Examples and Comparative Examples) The present invention will be described below with reference to Examples and Comparative Examples. In the descriptions of Examples and Comparative Examples, parts represent parts by weight.

Example 1 350 parts of methanol was poured onto 72,727 parts of dichlorodiphenylsilica at 24°C over a period of 30 minutes. The reaction temperature is 0
The temperature dropped to ℃. After stirring for 10 minutes, the by-produced aqueous chloride system was removed under foot pressure to obtain 2,679 parts of chloromethoxydiphenylsila.

Next, 670 parts of chloromethoxydiphenylsilica was added to 869 parts of methanol cooled to 0°C at a reaction temperature of 0 to 5°C.
After raining at a speed that maintains a
Disperse the crude dimethoxydiphenylsilane 341 in the lower layer.
Part i was collected. Subsequently, 1 part trT4 of chloromethoxydiphenylsilane SS was added to the methanol layer remaining in the reaction vessel, and 79% of crude dimethoxydiphenylsilane was added in the same manner.
Four parts were separated. Furthermore, 717 parts and 611 parts of chloromethoxydiphenylsilane were added dropwise, and 739 parts and 614 parts of crude dimethoxydiphenylsilane were separated. The reaction temperature was maintained at 0 to 5°C in all cases. Combine the dimethoxydiphenylsilane obtained from the above four times of spraying, and add 60
℃ and distilled methanol off under reduced pressure to obtain a purity of 97.
72,394 parts of 9% dimethoxydiphenylsilica were obtained.

Yield 91.0% (based on dichlorodiphenylsilane). Polymerization anastomosis i 1. o%.

Boiling point 153℃/l 01111Hp Nuclear magnetic resonance absorption (TMS) δppm=7.15~6.65 (101■, m)λ9
0(6H,a) Infrared absorption ('KBr) cm 2820.1590, 1430, 1190, 1120° 1080° Comparative example 1 56-60°C in 493 parts of methanol and 487 parts of 1.1.1-)lichloroethane Then, 489 parts of chloromethoxydiphenylsilane was added down in 1 hour to carry out a reaction.

The polymer content in the reaction mass was 50%. This reaction product was distilled under reduced pressure to give dimeth, xydiphenylsilica yxc+s8
I got it. Yield: 40.6% 0 Boiling point: 153°C/10 m a II Example 2 71013 parts of dichlorodiphenyl silica 184 parts of TLC ethanol were added dropwise at 20°C, and the same procedure as in Example 1 was repeated to obtain 7 runs of chloroethoxydiphenyl. 1050 copies were obtained.

Add 262 parts of chloroethoxydiphenyl 7 run to 461 parts of ethanol cooled to 0°C, and add 262 parts of chloroethoxydiphenyl 7 run as in Example 1.
Sequentially drop 2 parts, 262s, and 264 parts, stir, let stand,
Repeat the liquid separation operation (190 parts, 264 parts, 278 parts)
289 parts of crude jetoxydiphenylsilane were separated.

The dropping rate was adjusted so that the reaction temperature was maintained at 0 to 5°C. The jetoxydiphenylsila/s obtained through the above four operations were combined, and the remaining ethanol was distilled off under reduced pressure. The purity of the served jetoxydiphenylsila/ is 97
%, the polymer content was 0.5%, and the yield was 93% (based on dichlorodiphenylsilane).

Boiling point 155°C/lO■Hp Nuclear magnetic resonance absorption (TMS) δppm=7.10-7.70 (10H, m)a, 7s
(4u, q) Li2 (6H, t) Infrared absorption (KBr) 3-” 3000.1620, 1420, 1110° Patent applicant Arisakura Gosei Pharmaceutical Co., Ltd. Procedural amendment form) % formula % ■, Incident Indication of 1982 Patent Application No. 192569 2, Title of invention: Process for producing dialkoxydiphenylsilane 3, Relationship with the amended case Patent applicant: Organic Synthetic Pharmaceutical Industry Co., Ltd., 2-17-4 Kyobashi, Chuo-ku, Tokyo Company (1 other person) Representative Masao Tamashige 4, Agent 4-5 Kojimachi, Chiyoda-ku, Tokyo (102) 5, Date of amended order January 29, 1985, Yama°l-゛, Care , -,4,-1.

6. Column 7 of “Detailed Description of the Invention” of the specification to be amended, contents of the amendment (1) Clear aI @ r on page 3, lines 11-13 (Co
llect,.

... (omitted) - 3rd Edition, J has been changed to ``[Collection of Czechoslovakia Chemical Communications (Collection 7, Czec
h.

CheIIl, Con+mun, ) Volume 1976,
Page 110, Encyclopedia of Chemicals
Technology, 3rd edition (Encyclopedia)
of Chemical Technology+ 3
rd, Edit, ion, ) Jl and correct.

that's all

Claims (1)

[Claims] 1. A monovalent saturated alcohol is added to the alkoxychlorodiphenylsilane obtained by the reaction of dichlorodiphenylsilane and a monovalent saturated alcohol at a temperature range of -10 to 30°C, and the monovalent saturated alcohol is A method for producing dialkoxydiphenylsilane, which is characterized by reacting with saturated alcohol as a reaction solvent. 2. The manufacturing method according to claim 1, wherein the amount of monohydric saturated alcohol is 1.5 times or more in mole relative to the alkoxychlorosilane. 3. The production method according to claim 1, wherein the monohydric saturated alcohol is methanol, ethanol or propanol. 4. The manufacturing method according to claim 3, wherein the monohydric saturated alcohol is methanol.