WO2018157416A1

WO2018157416A1 - Process for synthesis of 3,3,3-trifluropropyl dimethylsilyl propylene ether

Info

Publication number: WO2018157416A1
Application number: PCT/CN2017/076699
Authority: WO
Inventors: 司林旭; 李佳琦; 居超凡; 吴君毅
Original assignee: 常熟三爱富中昊化工新材料有限公司; 内蒙古奥特普氟化学新材料开发有限公司
Priority date: 2017-02-28
Filing date: 2017-03-15
Publication date: 2018-09-07
Also published as: CN106977537A

Abstract

Disclosed is a process for the synthesis of 3,3,3-trifluropropyl dimethylsilyl propylene ether, the process comprising the following steps: (1) dimethyl monochlorosilane and propylene alcohol are added into a reactor, and a triethylamine catalyst and an n-hexane reaction solvent are then added, wherein the reaction process requires stirring, and during the process, a constant temperature oil bath is used for heating, and nitrogen is introduced; (2) after the reaction is completed, the product is left to stand for layering, and triethylamine hydrochloride in the lower layer is discharged to obtain crude 3,3,3-trifluropropyl dimethylsilyl propylene ether; and (3) the filtered crude 3,3,3-trifluropropyl dimethylsilyl propylene ether is rectified under a reduced pressure to obtain a high-purity 3,3,3-trifluropropyl dimethylsilyl propylene ether product. The 3,3,3-trifluropropyl dimethylsilyl propylene ether synthesized by the present invention has a lower raw material price, milder reaction conditions, and a safe and reliable reaction process; furthermore, the synthesis process is simple, has fewer side reactions, and produces less waste, wherein same is easy to treat, and the target product is easy to separate and has a high purity.

Description

Method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether

Technical field

The invention relates to a method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether, and belongs to the technical field of preparation methods of fluoroether compounds.

Background technique

Fluororubber has excellent properties such as high temperature resistance, solvent resistance, strong oxidant resistance, oil resistance and flame retardancy, so it has been widely used in aerospace, electronic communication, defense military, petrochemical and vehicle shipping. In recent years, with the rapid development and technological innovation in these fields, fluororubber as an irreplaceable high-performance material has not only greatly increased the demand, but also the application field is expanding. However, the traditional low-temperature resistance of fluororubber is not good. For example, in the case of fluorinated rubber, its low temperature resistance is generally as low as -30 °C, which is prone to brittle fracture, which does not meet the performance requirements of certain fields, such as in aerospace. In the field, because such equipment often flies at high speed in harsh environments, and because of the high safety requirements in the aerospace industry, higher requirements are placed on the performance of fluororubbers, and new fluororubbers are required to have lower brittleness. temperature. Fluoroether oligomers have excellent physical surface properties and low temperature resistance. They have been used in the manufacture of sealing materials, high temperature greases, coatings and surfactants in the 1980s, and are a development direction for the low temperature resistant fluororubber manufacturing industry in the future. . At present, the fluoroether oligomer can be obtained by emulsion polymerization of a novel fluoroether compound and a vinylidene fluoride or hexafluoropropylene monomer, and the product is vulcanized by kneading with a reinforcing agent, a structure controlling agent and a crosslinking agent. A new dry low temperature resistant rubber containing a special third monomer is obtained. The brittleness temperature of the rubber reaches -50 ° C, which fully meets the requirements of high-tech fields such as aerospace.

Summary of the invention

The object of the present invention is to provide a method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether which has a simple process route, is green and environmentally friendly, and has high product purity.

In order to achieve the above technical purpose, the technical solution of the present invention is:

(1) Dimethyl monochlorosilane and propylene alcohol were charged into the reactor, and then the catalyst triethylamine and the reaction solvent n-hexane were added, and the reaction was stirred while being heated using a constant temperature oil bath and nitrogen gas was introduced.

The reaction formula of the synthesis method is:

Preferably, the reactor volume is 200 ml to 2 L, the molar ratio of dimethyl monochlorosilane to propylene alcohol is 1:1.1 to 5, and the molar ratio of dimethyl monochlorosilane to triethylamine is 1:1.1 to 3, The amount of the alkane to be added is 50 to 250 ml, the reaction temperature is 40 to 100 ° C, the reaction pressure is 1 to 5 bar, and the reaction time is 1 to 6 hours.

(2) After completion of the reaction, the product was allowed to stand for stratification, and the lower triethylamine hydrochloride was discharged to give crude 3,3,3-trifluoropropyldimethylsilyl propyl ether.

Preferably, the product has a standing time of 40 to 70 minutes after the completion of the reaction.

(3) The crude 3,3,3-trifluoropropyldimethylsilyl propylene ether obtained by filtration is subjected to vacuum distillation to obtain high-purity 3,3,3-trifluoropropyldimethylsilane. Alkyl propylene ether products.

After the stratification, the rectification operation temperature is 50 to 150 ° C, and the operating pressure is 0.1 to 0.9 bar.

The invention has the advantages that the raw material for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether is lower, the reaction condition is mild, high temperature and high pressure are not required, the reaction process is safe and reliable, and the synthesis process is relatively simple. The side reaction is small, the waste generated is small and easy to handle, the target product is easy to separate, and the purity is high, which is a green process in line with industrial conditions.

detailed description

The detection tool for the product obtained in the following examples was an Agilent 6890N/5937 (GC/MS) gas chromatography/mass spectrometer.

Example 1

20 g of dimethylmonochlorosilane and 7.31 g of propenol were added to a 500 ml reactor, then 12.72 g of triethylamine and 200 g of n-hexane were added, and air was purged with nitrogen at a flow rate of 500 ml/min, and then used. The constant temperature oil bath was heated to 60 ° C, and stirred with a magnetic stirrer. After 1 h of reaction, the reaction product was poured into a funnel and allowed to stand for stratification. After 40 min, the lower liquid was discharged, and the liquid was 3,3,3-trifluoro. a crude product of propyldimethylsilyl propylene ether, which is then purified using a rectification column. When the operating temperature is 60 ° C and the operating pressure is 0.2 bar, the 3,3,3-trifluorocarbon in the overhead discharge The crude concentration of propyldimethylsilyl propylene ether was 99.10%.

Example 2

20 g of dimethylmonochlorosilane and 8.53 g of propenol were added to a 500 ml reactor, then 14.84 g of triethylamine and 200 g of n-hexane were added, and nitrogen was purged to remove air at a flow rate of 500 ml/min. The constant temperature oil bath was heated to 70 ° C, and stirred with a magnetic stirrer. After the reaction was carried out for 2 hours, the reaction product was poured into a funnel and allowed to stand for stratification. After 40 minutes, the lower liquid was discharged, and the liquid was 3,3,3-trifluoro. A crude product of propyldimethylsilyl propylene ether, which is then purified using a rectification column. When the operating temperature is 75 ° C and the operating pressure is 0.4 bar, the 3,3,3-trifluorocarbon in the overhead discharge The crude concentration of propyldimethylsilyl propylene ether was 99.35%.

Example 3

20 g of dimethylmonochlorosilane and 9.14 g of propenol were added to a 500 ml reactor, then 14.9 g of triethylamine and 200 g of n-hexane were added, and nitrogen was purged to remove air at a flow rate of 500 ml/min. The constant temperature oil bath was heated to 90 ° C, and stirred with a magnetic stirrer. After the reaction was carried out for 3 hours, the reaction product was poured into a funnel and allowed to stand for separation. After 40 minutes, the lower liquid was discharged, and the liquid was 3,3,3-trifluoro. A crude product of propyldimethylsilyl propylene ether, which is then purified using a rectification column. When the operating temperature is 85 ° C and the operating pressure is 0.1 bar, the 3,3,3-trifluorocarbon in the overhead discharge The crude concentration of propyldimethylsilyl propylene ether was 99.81%.

Example 4

20 g of dimethylmonochlorosilane and 8.53 g of propenol were added to a 500 ml reactor, then 14.84 g of triethylamine and 200 g of n-hexane were added, and nitrogen was purged to remove air at a flow rate of 500 ml/min. The constant temperature oil bath was heated to 40 ° C, and stirred at the same time using a magnetic stirrer. After the reaction was carried out for 6 hours, the reaction product was poured into a funnel and allowed to stand for separation. After 60 minutes, the lower liquid was discharged, and the liquid was 3,3,3-trifluoro. A crude product of propyldimethylsilyl propylene ether, which is then purified using a rectification column. When the operating temperature is 50 ° C and the operating pressure is 0.7 bar, the 3,3,3-trifluorocarbon in the overhead discharge The crude concentration of propyldimethylsilyl propylene ether was 99.31%.

Example 5

20 g of dimethylmonochlorosilane and 7.31 g of propenol were added to a 500 ml reactor, then 12.72 g of triethylamine and 200 g of n-hexane were added, and nitrogen was purged through air at a flow rate of 500 ml/min. Then, the mixture was heated to 100 ° C in a constant temperature oil bath, and stirred by a magnetic stirrer. After the reaction was carried out for 4 hours, the reaction product was poured into a funnel and allowed to stand for stratification. After 70 minutes, the lower liquid was discharged, and the liquid was 3, 3, 3 A crude product of trifluoropropyldimethylsilyl propylene ether, which is then purified using a rectification column. When the operating temperature is 150 ° C and the operating pressure is 0.9 bar, the top discharge is 3, 3, 3 The crude concentration of trifluoropropyldimethylsilyl propylene ether was 99.26%.

The above embodiments are not intended to limit the invention in any way, and all the technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

A method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether, comprising the steps of:

(1) adding dimethyl monochlorosilane and propylene alcohol to the reactor, and then adding the catalyst triethylamine and the reaction solvent n-hexane, the reaction process needs to be stirred, while heating using a constant temperature oil bath and introducing nitrogen;

(2) After completion of the reaction, the product is allowed to stand for separation, and the lower layer of triethylamine hydrochloride is discharged to obtain a crude 3,3,3-trifluoropropyldimethylsilyl propylene ether;

(3) The crude 3,3,3-trifluoropropyldimethylsilyl propylene ether obtained by filtration is subjected to vacuum distillation to obtain high-purity 3,3,3-trifluoropropyldimethylsilane. Alkyl propylene ether products.
The method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether according to claim 1, wherein in the step (1), the volume of the reactor is 200 ml. 2L.
The method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether according to claim 1, wherein in the step (1), the dimethyl chloride The molar ratio of silane to propylene alcohol is 1:1.1 to 5, the molar ratio of dimethylmonochlorosilane to triethylamine is 1:1.1 to 3, and the amount of n-hexane added is 50 to 250 ml.
The method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether according to claim 1, wherein in the step (1), the reaction temperature is 40 to 100 ° C The reaction pressure is 1 to 5 bar, and the reaction time is 1 to 6 hours.
The method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether according to claim 1, wherein in the step (2), the product standing time is 40 ～ 70min.
The method for synthesizing 3,3,3-trifluoropropyldimethylsilyl propylene ether according to claim 1, wherein in the step (3), the operating temperature of the rectification column is 50 to 150 ° C, operating pressure is 0.1 to 0.9 bar.