A method for preparing 3-octanoylthiopropyltriethoxysilane by a green ball milling method

Abstract

This invention belongs to the field of organic synthesis technology, and proposes a green method for the preparation of 3-octanoylthiopropyltriethoxysilane by ball milling, using a polyacid catalyst HPMo. 12 O 39 (1-iPrlM)4, 3-(triethoxysilyl)propanethiol, octanoic acid, and zirconium oxide balls were sequentially added to a ball mill jar. The jar was fixed on a ball mill and reacted at 300 r / min for 2 h at room temperature. The jar was then removed and washed three times with petroleum ether. The petroleum ether was combined and filtered, and the zirconium oxide balls and polyacid catalyst on the filter paper were recovered and recycled. The petroleum ether filtrate was rotary evaporated and dried to obtain the product NXT. This invention provides a green and rapid synthesis of NXT using a solvent-free ball milling method at room temperature. The method is simple, easy to operate, and the catalyst and petroleum ether are recyclable. The product is water-free, environmentally friendly, and has good atom economy.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, and particularly relates to a green method for preparing 3-octanoylthiopropyltriethoxysilane by ball milling. Background Technology

[0002] 3-Octaylthiopropyltriethoxysilane (NXT) is a very important and widely used silane coupling agent. Significant progress has been made in the synthesis of NXT in recent decades, but certain limitations remain. These include the use of toxic and difficult-to-recover catalysts, corrosive substrates, difficulty in controlling reaction rates, relatively stringent reaction conditions, and low atom economy. Therefore, selecting an economical and environmentally friendly catalytic system for the simple, efficient, atom-economical, pollution-free, and industrially viable synthesis of NXT under mild conditions remains of high research value.

[0003] Polyacids, due to their unique acidity and redox properties, are multifunctional catalysts with high catalytic activity and good stability, playing a crucial role in catalysis, biochemical analysis, and electron microscopy. They can be used as phase transfer catalysts in homogeneous and heterogeneous reactions, and importantly, they are typical green catalysts that do not pollute the environment.

[0004] In organic reactions, mechanochemical ball milling can efficiently promote organic reactions in a more environmentally friendly way. The main advantages of mechanochemical ball milling include: 1. No or minimal solvent required: The reaction takes place in the solid phase, significantly reducing the use of organic solvents and making it environmentally friendly; 2. High reaction efficiency: Solid reactants are directly activated by mechanical energy, resulting in short reaction times and high efficiency; 3. Wide applicability: It can synthesize compounds that are difficult to prepare using conventional solution methods and can achieve room temperature reactions, avoiding the risk of thermal decomposition; 4. Simple operation: The process flow is simple and easy to scale up for production.

[0005] Currently, among the known technologies for preparing 3-octanoylthiopropyltriethoxysilane, there are few solvent-free synthesis methods that use polyacids as catalysts and ball milling as a key technique. Although some synthesis methods also adopt the concept of solvent-free or even catalyst-free reactions, the reaction requires many control factors, and some synthesis techniques still have the problem of complicated steps in specific operations. Summary of the Invention

[0006] This invention addresses the aforementioned technical problems in the synthesis of NXT by proposing a green method for the ball milling synthesis of 3-octanoylthiopropyltriethoxysilane, using the polyacid HPMo 12 O 39Using (1-iPrlM)4 as a catalyst, and 3-(triethoxysilyl)propanethiol and octanoic acid as substrates, a green and rapid ball milling method is used to synthesize NXT at room temperature without solvent. This method has the advantages of being simple, easy to operate, having recyclable catalyst and petroleum ether, and producing products that are water-free, environmentally friendly, and atom-economical.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The present invention provides a green synthesis method for 3-octanoylthiopropyltriethoxysilane using a ball milling method, comprising the following specific steps:

[0008] S1. Based on the amount of substance, HPMo 12 O 39 • (1-iPrlM)4, 3-(triethoxysilyl)propanethiol, and octanoic acid were added sequentially to the ball mill jar along with zirconia balls with a diameter of 1.0 mm in a ratio of 1:10:10.

[0009] S2. Seal the ball mill jar, fix it on the vibrating arm of the ball mill, and react at a rate of 300 r / min for 2 hours at room temperature;

[0010] S3. Remove the ball mill jar from the ball mill and wash it three times with petroleum ether.

[0011] S4. After merging the petroleum ether, filter the mixture and recover the zirconium oxide microspheres and polyacid catalyst from the filter paper for recycling. Then, evaporate and dry the petroleum ether filtrate to obtain the product NXT, with a yield greater than 85%.

[0012] As a preferred option, HPMo 12 O 39 The amounts of (1-iPrlM)4, 3-(triethoxysilyl)propanethiol, and octanoic acid were 0.05 mmol, 0.5 mmol, and 0.5 mmol, respectively. The HPMo 12 O 39 The molar percentage of (1-iPrlM)4 was 10 mol%, the mass of the product NXT was 170 mg, and the yield was 92%.

[0013] Preferably, the ball mill is a Planetary Ball Mill PM 100, and the ball ink container has a capacity of 50 mL, with zirconia balls weighing 15 g.

[0014] Preferably, the volume of petroleum ether used for each wash is 20 mL.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0016] This invention provides a green method for the preparation of 3-octanoylthiopropyltriethoxysilane via ball milling, using the polyacid HPMo 12 O 39 Using (1-iPrlM)4 as a catalyst, and 3-(triethoxysilyl)propanethiol and octanoic acid as substrates, a green and rapid ball milling method is used to synthesize NXT at room temperature without solvent. This method has the advantages of being simple, easy to operate, having recyclable catalyst and petroleum ether, and producing products that are water-free, environmentally friendly, and atom-economical. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 HPMo 12 O 39 The reaction equation for the synthesis of 3-octanoylthiopropyltriethoxysilane by (1-iPrlM)4 catalytic ball milling method;

[0019] Figure 2 The 1H NMR spectrum of 3-octanoylthiopropyltriethoxysilane;

[0020] Figure 3 The carbon NMR spectrum of 3-octanoylthiopropyltriethoxysilane;

[0021] Figure 4 HPMo 12 O 39 ·Structure diagram of (1-iPrlM)4;

[0022] Figure 5 HPMo 12 O 39 Data from 5 cycles of (1-iPrlM)4. Detailed Implementation

[0023] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0024] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0025] Example 1: This example provides a green synthesis method for 3-octanoylthiopropyltriethoxysilane using ball milling. Specific steps include: ... 12 O 39 •(1-iPrlM)4 (0.025 mmol, 5 mol%), 3-(triethoxysilyl)propanethiol (0.5 mmol), octanoic acid (0.5 mmol), and 15 g zirconia balls (1.0 mm in diameter) were sequentially added to a 50 mL ball mill jar containing solvent. The jar was sealed and fixed on the vibrating arm of a Planetary Ball Mill PM 100, and reacted at 300 r / min for 2 h at room temperature. The jar was removed from the ball mill, and petroleum ether was added three times to wash the jar, 20 mL each time. The petroleum ether was combined and filtered, and the zirconia balls on the filter paper were recovered along with the catalyst. 60 mL of the filtrate petroleum ether was treated by rotary evaporation and dried to obtain the product NXT, with a mass of 155 mg and a yield of 80%.

[0026] Example 2: This example provides a green synthesis method for 3-octanoylthiopropyltriethoxysilane using ball milling. Specific steps include: HPMo... 12 O 39 (1-iPrlM)4 (0.05 mmol, 10 mol%), 3-(triethoxysilyl)propanethiol (0.5 mmol), octanoic acid (0.5 mmol), and 15 g zirconia balls (1.0 mm in diameter) were sequentially added to a 50 mL ball mill jar. The jar was sealed and fixed on the vibrating arm of a Planetary Ball Mill PM 100 ball mill, and reacted at 300 r / min for 2 h at room temperature. The jar was removed from the ball mill, and petroleum ether was added three times to wash the jar, 20 mL each time. The petroleum ether was combined and filtered, and the zirconia balls on the filter paper were recovered along with the catalyst. 60 mL of the filtrate petroleum ether was treated by rotary evaporation and dried to obtain the product NXT, with a mass of 170 mg and a yield of 92%.

[0027] Example 3: This example provides a green synthesis method for 3-octanoylthiopropyltriethoxysilane using ball milling. Specific steps include: HPMo... 12 O 39(1-iPrlM)4 (0.10 mmol, 20 mol%), 3-(triethoxysilyl)propanethiol (0.5 mmol), octanoic acid (0.5 mmol), and 15 g zirconia balls (1.0 mm in diameter) were sequentially added to a 50 mL ball mill jar. The jar was sealed and fixed on the vibrating arm of a Planetary Ball Mill PM 100 ball mill, and reacted at 300 r / min for 2 h at room temperature. The jar was removed from the ball mill, and petroleum ether was added three times to wash the jar, 20 mL each time. The petroleum ether was combined and filtered, and the zirconia balls on the filter paper were recovered along with the catalyst. 60 mL of the filtrate petroleum ether was treated by rotary evaporation and dried to obtain the product NXT, with a mass of 170 mg and a yield of 92%.

[0028] like Figure 1 As shown, HPMo in Examples 1-3 12 O 39 The reaction process for synthesizing 3-octanoylthiopropyltriethoxysilane via (1-iPrlM)4-catalyzed ball milling; wherein, the polyacid catalyst HPMo 12 O 39 The structural diagram of (1-iPrlM)4 is shown below. Figure 4 As shown.

[0029] like Figures 2-3 As shown, the 1H and 1C NMR spectra of 3-octanoylthiopropyltriethoxysilane, i.e., NXT, are described below:

[0030] 1 H NMR (500 MHz, CDCl3 / TMS): δ 3.83-3.79 (m, 6H), δ 2.89 (t, J = 7.5Hz, 2H), δ 2.53 (t, J = 7.5 Hz, 2H), δ 1.68-1.65 (m, 4H), δ 1.29-1.20 (m,17H), δ 0.88 (t, J = 7.5 Hz, 3H), δ 0.72-0.69 (m, 2H); 13 C NMR (126 MHz, CDCl3 / TMS): 199.28, 58.24, 44.00, 31.55, 28.85, 28.81, 25.61, 23.29, 22.50,18.17, 13.93, 9.85, 9.39.

[0031] like Figure 5As shown in the results of the catalyst recycling experiment, considering environmental friendliness and economic practicality, it is meaningful to completely recover the catalyst and solvent in the reaction system. After the reaction is completed, the polyacid catalyst is recovered by filtration, the petroleum ether can be recovered by rotary evaporation, and the product is collected directly without any special requirements or further processing. The recycling experiment results show that the catalyst still has catalytic effect after five separation cycles, indicating its potential for industrial application.

[0032] Based on the effect of the amount of polyacid catalyst on the reaction results in Examples 1 to 3, the polyacid catalyst in Example 2, namely HPMo 12 O 39 Doubling the amount and molar percentage of (1-iPrlM)4 positively impacts both the quality and yield of the NXT product. However, in Example 3, further increasing the amount of the polyacid catalyst did not increase the quality or yield of the NXT product. Therefore, besides the type of polyacid catalyst itself being important, its formulation is crucial for the green synthesis of NXT, and the optimal reaction conditions were determined to be 0.5 mmol and 10 mol% of the polyacid catalyst.

[0033] In Examples 1-3, the use of 15g of 1.0mm zirconia balls in a 50mL ball mill jar and a Planetary Ball Mill PM 100 is significant for the following reasons: 1) The number of small balls is far greater than that of 3-5mm large balls of the same mass, resulting in more collision points, easier ultrafine crushing of powder, and full reaction of solid phase, which is beneficial for microscopic mixing of reactants; 2) The raw materials can be ground to the micron / submicron level, making it easy for the target components to be dissolved by the solvent during subsequent petroleum ether washing, greatly improving the efficiency of three-wash extraction and reducing product encapsulation residue; 3) The jar has a low filling rate, allowing for sufficient flow of materials and solvents within the jar; 4) The grinding residue of the small balls has a fine and uniform particle size, resulting in a stable filtration speed, less clogging of filter paper, and improved solid-liquid separation efficiency.

[0034] Furthermore, leveraging the advantages of the PM100 Lech planetary ball mill, the combined centrifugal force of revolution and the impact force of rotation gives the small balls high impact and shear force, ensuring sufficient kinetic energy for the small zirconium balls. This compensates for the shortcomings of small particle size and insufficient weight per particle, achieving ultrafine grinding. The ball mill exhibits low vibration during both no-load and material-carrying operation, stable ball movement trajectory, good grinding repeatability, and small errors in parallel experimental data.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A green synthesis method for 3-octanoylthiopropyltriethoxysilane by ball milling, characterized in that, The specific steps include the following: S1. Based on the amount of substance, HPMo 12 O 39 • (1-iPrlM)4, 3-(triethoxysilyl)propanethiol, and octanoic acid were added sequentially to the ball mill jar along with zirconia balls with a diameter of 1.0 mm in a ratio of 1:10:

10. S2. Seal the ball mill jar, fix it on the vibrating arm of the ball mill, and react at a rate of 300 r / min for 2 hours at room temperature; S3. Remove the ball mill jar from the ball mill and wash it three times with petroleum ether. S4. After merging the petroleum ether, filter the mixture and recover the zirconium oxide microspheres and polyacid catalyst from the filter paper for recycling. Then, evaporate and dry the petroleum ether filtrate to obtain the product NXT, with a yield greater than 85%.

2. The method for preparing 3-octanoylthiopropyltriethoxysilane by ball milling according to claim 1, characterized in that, HPMo 12 O 39 The amounts of (1-iPrlM)4, 3-(triethoxysilyl)propanethiol, and octanoic acid were 0.05 mmol, 0.5 mmol, and 0.5 mmol, respectively. The HPMo 12 O 39 The molar percentage of (1-iPrlM)4 was 10 mol%, the mass of the product NXT was 170 mg, and the yield was 92%.

3. The method for preparing 3-octanoylthiopropyltriethoxysilane by ball milling according to claim 2, characterized in that, The ball mill is a Planetary Ball Mill PM 100, and the ball ink container has a capacity of 50 mL, with zirconia balls weighing 15 g.

4. The method for preparing 3-octanoylthiopropyltriethoxysilane by ball milling according to claim 3, characterized in that, The volume of petroleum ether used for each wash is 20 mL.

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