A preparation method of KH-560
By using a combination of cobalt catalyst and catalyst promoter, and optimizing reaction conditions, the formation of β-isomer was successfully suppressed, solving the problems of low yield and difficult purification of KH-560 in the prior art, and realizing efficient and low-cost KH-560 synthesis.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WANHUA CHEM GRP CO LTD
- Filing Date
- 2024-12-02
- Publication Date
- 2026-06-02
AI Technical Summary
In existing technologies, platinum catalysts are expensive and difficult to recycle, have long reaction times, and cobalt and rhodium catalysts generate a high proportion of β-isomers during the synthesis of KH-560, resulting in a reduced yield of KH-560 and difficulty in purification.
Trimethoxysilane and allyl glycidyl ether were used as raw materials. The reaction was carried out in the presence of a cobalt catalyst and catalyst promoters (such as tetrahydrofuran, diethyl ether, acetonitrile, etc.). The reaction conditions were controlled to suppress the formation of β-isomers. Cobalt catalysts such as cobalt acetylacetonate were used, and KH-560 product was obtained by vacuum distillation.
A low-cost and efficient synthesis of KH-560 was achieved, which inhibited the formation of β-isomers, improved the yield, and simplified the purification process, with yields reaching 93.0%-92.1%.
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Figure BDA0005164217770000021
Abstract
Description
Technical Field
[0001] This invention belongs to the field of fine chemical synthesis, specifically relating to a method for preparing KH-560. Background Technology
[0002] KH-560, chemically known as γ-(2,3-epoxypropoxy)propyltrimethoxysilane, has become one of the most well-known and widely used reactions in the organosilicon field since the discovery of hydrosilylation reactions in 1947. The synthesis of KH-560 is one of its most mature applications. As a common silane coupling agent, KH-560 is frequently used in adhesives, sealants, electronic molding compounds, and fiberglass industries.
[0003] The most common catalyst in the synthesis of KH-560 is platinum catalyst, such as those described in US4820674A and US20100036146A1. These patents provide detailed descriptions of platinum-catalyzed synthesis of KH-560. However, platinum catalysts are expensive, difficult to recycle, and have long induction times during the reaction. Other catalysts, such as cobalt and rhodium, are also used in the synthesis of KH-560, as described in CN117362334A. In these methods, a high proportion of β-isomers is generated during the reaction. β-isomers have a very similar structure and boiling point to KH-560, leading to a lower yield of KH-560 and making it difficult to separate from the product KH-560. Current technologies do not address this issue. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention provides a method for preparing KH-560, which uses a cobalt catalyst, is low in cost, has a short induction time, and exhibits high positional and stereoselectivity in the presence of a catalytic promoter. This method effectively solves the problem of high β-isomer content leading to reduced yield and difficulty in purification.
[0005] To achieve the above objectives, this invention proposes a method for preparing KH-560, the technical solution of which is as follows:
[0006] A method for preparing KH-560, which uses trimethoxysilane and allyl glycidyl ether as raw materials, and reacts them in the presence of a cobalt catalyst and a catalyst aid to obtain KH-560.
[0007] Specifically, it includes the following steps:
[0008] S1. Mix allyl glycidyl ether with catalyst promoter;
[0009] S2, add cobalt catalyst and trimethoxysilane, and after the reaction is kept at the temperature for a period of time, the crude product KH-560 is obtained;
[0010] S3. The crude product is subjected to vacuum distillation to obtain product KH-560.
[0011] Preferably, the catalyst aid in S1 is an ether or nitrile substance, preferably selected from one or more of tetrahydrofuran, diethyl ether, acetonitrile, and propionitrile, and more preferably tetrahydrofuran.
[0012] Preferably, the molar ratio of the catalyst promoter to allyl glycidyl ether in S1 is 1:3-3:1, more preferably 1:1-2:1.
[0013] Preferably, the mixing temperature in S1 is controlled at 50-70℃, which is beneficial for subsequent reactions.
[0014] Preferably, the cobalt catalyst in S2 is one or more of cobalt(II) acetylacetonate, cobalt(II) bis(cyclopentadiene)cobalt(II) and cobalt octacarbonyl, with cobalt(II) acetylacetonate being the most preferred.
[0015] Preferably, the amount of cobalt catalyst used in S2 is 0.001wt%-0.003wt%, based on the total mass of trimethoxysilane and allyl glycidyl ether.
[0016] Preferably, the molar ratio of trimethoxysilane to allyl glycidyl ether in S2 is 1:1 to 1:1.3.
[0017] Preferably, the addition rate of trimethoxysilane in S2 is controlled, thereby controlling the reaction temperature of S2 to be 55-85℃.
[0018] Preferably, the heat preservation time after adding trimethoxysilane to S2 is 1-3 hours.
[0019] Preferably, the vacuum distillation in step S3 can be carried out under conditions commonly used in the art, and the present invention does not impose any special limitations.
[0020] In a preferred embodiment, before the reaction, the entire reaction system is purged with nitrogen to maintain a slightly positive nitrogen pressure. The preferred nitrogen purging time is 10-20 minutes.
[0021] The reaction equation for the preparation method of KH-560 described in this invention is as follows:
[0022]
[0023] Compared with the prior art, the outstanding advantages of this invention are as follows:
[0024] This invention provides a novel catalyst combination for the synthesis of KH-560. This catalyst combination is low in cost, highly efficient, and exhibits high positional and stereoselectivity in the presence of a catalyst promoter. By optimizing the process and catalyst combination, the formation of β-isomers is suppressed, effectively solving the problems of low KH-560 yield and difficult product purification caused by a high proportion of β-isomers. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are merely illustrative and are not intended to limit the invention.
[0026] β-Isomer test method: The crude KH-560 product was tested using an Agilent GC-8890 gas chromatograph to detect whether it contained β-isomers and their content.
[0027] Example 1
[0028] The reactor was purged with nitrogen for 20 minutes and maintained under a slight positive nitrogen pressure. 136.9 g of allyl glycidyl ether and 86.5 g of tetrahydrofuran were added. Heating and stirring were started. When the temperature reached 60°C, 5.2 mg of cobalt(II) acetylacetonate catalyst was added, and stirring was continued for 10 minutes. Then, 122.1 g of trimethoxysilane was added dropwise. The dropping rate was controlled to maintain the reaction solution temperature at approximately 70°C. After the addition was complete, the mixture was kept at 60°C for 1.5 hours to obtain the crude product KH-560.
[0029] The crude product was tested and no β-isomer was detected. After vacuum distillation at 140℃ and 0.1mbar, 219.8g of KH-560 product was obtained, with a yield of 93.0% (calculated based on trimethoxysilane, the same below).
[0030] Example 2
[0031] The reactor was purged with nitrogen for 20 minutes and maintained under a slight positive nitrogen pressure. 136.5 g of allyl glycidyl ether and 49.3 g of acetonitrile were added. Heating and stirring were started. When the temperature reached 65°C, 5.0 mg of cobalt(II) acetylacetonate catalyst was added, and stirring was continued for 10 minutes. Then, 122.5 g of trimethoxysilane was added dropwise. The dropping rate was controlled to maintain the reaction solution temperature at approximately 70°C. After the addition was complete, the mixture was kept at 60°C for 1.5 hours to obtain the crude product KH-560.
[0032] The crude product was tested and no β-isomer was detected. After vacuum distillation at 140℃ and 0.1mbar, 218.6g of KH-560 product was obtained, with a yield of 92.5%.
[0033] Example 3
[0034] The reactor was purged with nitrogen for 20 minutes and maintained under a slight positive nitrogen pressure. 125.5 g of allyl glycidyl ether and 82.1 g of tetrahydrofuran were added. Heating and stirring were started. When the temperature reached 60°C, 6.2 mg of bis(cyclopentadiene)cobalt(II) catalyst was added, and the mixture was stirred for 10 minutes. Then, 122.1 g of trimethoxysilane was added dropwise. The dropping rate was controlled to maintain the reaction solution temperature at approximately 65°C. After the addition was complete, the mixture was kept at 60°C for 1.5 hours to obtain the crude product KH-560.
[0035] The crude product was tested and no β-isomer was detected. After vacuum distillation at 140℃ and 0.1mbar, 217.0g of KH-560 product was obtained, with a yield of 91.8%.
[0036] Example 4
[0037] The reactor was purged with nitrogen for 20 minutes and maintained under a slight positive nitrogen pressure. 137.1 g of allyl glycidyl ether and 43.9 g of tetrahydrofuran were added. Heating and stirring were started. When the temperature reached 60°C, 5.8 mg of cobalt(II) acetylacetonate catalyst was added, and stirring was continued for 10 minutes. Then, 122.7 g of trimethoxysilane was added dropwise. The dropping rate was controlled to maintain the reaction solution temperature at approximately 75°C. After the addition was complete, the mixture was kept at 60°C for 1.5 hours to obtain the crude product KH-560.
[0038] The crude product was tested and no β-isomer was detected. After vacuum distillation at 140℃ and 0.1mbar, 217.7g of KH-560 product was obtained, with a yield of 92.1%.
[0039] Comparative Example 1
[0040] The cobalt(II) acetylacetonate catalyst in Example 1 was replaced with cobalt acetate tetrahydrate, and tetrahydrofuran was not added. Otherwise, the reaction was the same as in Example 1. After the reaction was completed, gas chromatography detected that the β-isomer content in the crude product was 3.02 wt%. After vacuum distillation, 196.4 g of KH-560 product was obtained, with a yield of 83.1%.
[0041] Comparative Example 2
[0042] Compared with Example 1, tetrahydrofuran was not added, but everything else was the same as in Example 1. After the reaction was completed, gas chromatography detected that the β-isomer content was 1.57%. After vacuum distillation, 189.5g of KH-560 product was obtained, with a yield of 80.2%.
[0043] In summary, this invention uses trimethoxysilane and allyl glycidyl ether as raw materials to synthesize KH-560 in the presence of a cobalt catalyst and its auxiliaries. This reaction is not only low in cost and highly efficient, but also overcomes the problems of low yield and difficult purification caused by β-isomers, providing a new approach for the high-yield and economical synthesis of KH-560.
Claims
1. A method for preparing KH-560, characterized in that: Includes the following steps: S1. Mix allyl glycidyl ether with catalyst promoter; S2, add cobalt catalyst and trimethoxysilane, and after the reaction is kept at the temperature, the crude product is obtained; S3. The crude product is subjected to vacuum distillation to obtain product KH-560; The catalyst promoter is an ether or a nitrile substance.
2. The method according to claim 1, characterized in that: The catalyst promoter in step S1 is selected from one or more of tetrahydrofuran, diethyl ether, acetonitrile, and propionitrile.
3. The method according to claim 1, characterized in that: The molar ratio of the catalyst promoter to allyl glycidyl ether in step S1 is 1:3-3:1, preferably 1:1-2:
1.
4. The method according to claim 1, characterized in that: The mixing temperature in step S1 is 50-70℃.
5. The method according to claim 1, characterized in that: The cobalt catalyst in step S2 is one or more of cobalt(II) acetylacetonate, cobalt(II) bis(cyclopentadiene) and cobalt(octacarbonyl).
6. The method according to claim 1 or 5, characterized in that: The amount of cobalt catalyst used in step S2 is 0.001wt%-0.003wt%, based on the total mass of trimethoxysilane and allyl glycidyl ether.
7. The method according to claim 1, characterized in that, In step S2, the molar ratio of trimethoxysilane to allyl glycidyl ether is 1:1 to 1:1.
3.
8. The method according to claim 1, characterized in that: The reaction temperature in step S2 is 55-85℃.
9. The method according to claim 1, characterized in that: The heat preservation time in step S2 is 1-3 hours.
10. KH-560 prepared by the preparation method according to any one of claims 1-9.