Synthesis method of propargyl alcohol

Abstract

The invention discloses a synthesis method of propargyl alcohol, calcium carbide, formaldehyde and / or polyformaldehyde and water react in an organic solvent in the presence of a catalyst and basic carbonate to obtain propargyl alcohol, the catalyst comprises a quaternary ammonium salt catalyst and / or a cesium carbonate catalyst, and the organic solvent comprises dimethyl sulfoxide. Compared with a traditional synthesis method, the propargyl alcohol synthesis method has the advantages that the catalyst is easier to obtain and lower in price, the requirement on equipment is lower, the operation is simpler and more convenient, and propargyl alcohol can be prepared with lower cost and higher efficiency. In addition, the propargyl alcohol synthesis method is safe in reaction and free of escape of a large amount of gas, and a closed reaction container does not need to be specially used. The propargyl alcohol synthesis method is more suitable for industrial production of propargyl alcohol and has higher economic benefits.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, and specifically to a method for synthesizing propynyl alcohol. Background Technology

[0002] Propargyl alcohol is an important basic chemical raw material with wide industrial applications. It is a crucial intermediate in the preparation of tazobactam, vitamin A, and allyl alcohol, and also has broad applications in pesticides, chemicals, electroplating, and oil extraction. With the continuous expansion of downstream applications in pharmaceuticals, electroplating, and metallurgy, the demand for propargyl alcohol is expected to increase significantly in the future.

[0003] Currently, the main industrial method for synthesizing propynyl alcohol is the Reppe process (acetylacetonate-aldehyde process). This involves adding an aqueous formaldehyde solution and a copper-based catalyst (such as cuprous acetylenide or copper-bismuth catalyst) to a reactor, introducing acetylene gas, and maintaining the pressure at 0.1-0.3 MPa. Under the action of the copper-based catalyst, formaldehyde and acetylene undergo an addition reaction to produce propynyl alcohol. The biggest drawback of this method is its poor safety; the production and use of acetylene carries an explosion risk. This method requires strict control of temperature and pressure; otherwise, the propynyl alcohol yield is low, and there are numerous side reactions. This not only wastes raw materials but also complicates subsequent separation and purification processes, increasing overall production costs and energy consumption. Furthermore, copper-based catalysts are relatively expensive and prone to deactivation after prolonged reactions, requiring frequent replacement or regeneration, further impacting production continuity and economic efficiency. In addition, industrial acetylene gas production is mainly achieved through the reaction of calcium carbide (mainly calcium carbide, CaC2) with water. However, traditional calcium carbide-water reactions often struggle to precisely control the reaction rate, easily leading to excessively vigorous reactions that result in large amounts of acetylene gas escaping, causing waste and posing safety hazards. Therefore, the safety and economic benefits of the Reppe method need to be further improved.

[0004] Other less common methods for synthesizing propyne alcohols include propyne hydrogenation and electrochemical methods. Propyne hydrogenation involves hydrogenating propyne; the conditions are mild, but the raw material costs are high. The electrochemical method is an emerging process that prepares propyne aldehydes through electrolytic reduction; it is environmentally friendly, but its industrialization potential is low. Therefore, the Reppe method remains the mainstream process at present.

[0005] To improve the economic efficiency of propargyl alcohol production and promote its application in multiple fields, it is necessary to develop simpler and more economical synthesis methods. Summary of the Invention

[0006] The purpose of this invention is to provide a simple, economical, and highly selective method for synthesizing propynyl alcohol directly from calcium carbide.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a method for synthesizing propynyl alcohol, wherein calcium carbide, formaldehyde and / or polyoxymethylene react with water in an organic solvent in the presence of a catalyst and alkaline carbonate to obtain propynyl alcohol. The catalyst includes quaternary ammonium salt catalysts and / or cesium carbonate catalysts. The organic solvent includes dimethyl sulfoxide.

[0008] In some embodiments, the quaternary ammonium salt catalyst includes one or more of tetraalkylammonium fluoride catalysts, tetraalkylammonium chloride catalysts, tetraalkylammonium bromide catalysts, and tetraalkylammonium acetate catalysts.

[0009] In some embodiments, the alkaline carbonate includes potassium and / or sodium salts.

[0010] In some embodiments, the molar ratio of the catalyst to the alkaline carbonate is 1:(0.1~10), for example 1:0.1, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1:5.5, 1:6, 1:6.5, 1:7, 1:7.5, 1:8, 1:8.5, 1:9, 1:9.5, 1:10.

[0011] In some specific embodiments, the quaternary ammonium salt catalyst includes one or more of tetramethylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, tetramethylammonium bromide, tetraethylammonium bromide, tetrabutylammonium bromide, tetramethylammonium fluoride, tetraethylammonium fluoride, tetrabutylammonium fluoride, tetramethylammonium acetate, tetraethylammonium acetate, and tetrabutylammonium acetate.

[0012] In some specific embodiments, the alkaline carbonate includes one or more of sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0013] In some embodiments, the organic solvent may also selectively include tetrahydrofuran, N,N -Dimethylformamide, N One or more of the following: 1,2-methylpyrrolidone, 1,2-dichloroethane, 1,2-dibromoethane, ethanol, methanol, isopropanol, ethyl acetate, dioxane, acetone, acetonitrile, and toluene.

[0014] In some embodiments, the dimethyl sulfoxide accounts for 40 wt.% to 100 wt.% of the organic solvent, for example, 40 wt.%, 45 wt.%, 50 wt.%, 55 wt.%, 60 wt.%, 65 wt.%, 70 wt.%, 75 wt.%, 80 wt.%, 85 wt.%, 90 wt.%, 95 wt.%, 100 wt.%.

[0015] In some specific and preferred embodiments, the organic solvent further includes tetrahydrofuran, N,N -Dimethylformamide, N One or more of methylpyrrolidone.

[0016] In some specific and preferred embodiments, the dimethyl sulfoxide accounts for 40 wt.% to 80 wt.% of the organic solvent, more preferably 45 wt.% to 70 wt.%, and even more preferably 45 wt.% to 60 wt.%.

[0017] In some embodiments, the reaction temperature is 20°C to 90°C, for example 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C.

[0018] In some preferred embodiments, the reaction temperature is 35°C to 80°C. More preferably, the reaction temperature is 40°C to 60°C.

[0019] In some preferred embodiments, the purity of the calcium carbide is 70% to 100%, for example, any purity between any two of 70%, 75%, 80%, 85%, 90%, 95%, 100% or higher.

[0020] In some preferred embodiments, the reaction time is 10 h to 24 h. More preferably, the reaction temperature is 15 °C to 20 °C, and more preferably 16 °C to 18 °C.

[0021] In some preferred embodiments, the degree of polymerization n of the paraformaldehyde is 5 to 100, for example, the degree of polymerization n is any degree of polymerization between any two of the following: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100 or above.

[0022] In some embodiments, the molar ratio of calcium carbide in the calcium carbide to formaldehyde in the reaction system is 1:(0.5~3), for example, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3. The formaldehyde in the reaction system includes formaldehyde fed directly and formaldehyde depolymerized from the polymethyl methacrylate (PMMA). If formaldehyde is fed directly, the amount of formaldehyde in the reaction system is the amount fed directly. If it is fed in the form of PMMA, the formaldehyde in the reaction system is the formaldehyde depolymerized from PMMA. If it is fed in a mixed form of methanol and PMMA, the formaldehyde in the reaction system consists of formaldehyde fed directly and formaldehyde depolymerized from PMMA.

[0023] In some embodiments, the molar amount of the catalyst is 1% to 20% of the molar amount of calcium carbide in the calcium carbide, for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%.

[0024] In some embodiments, the molar amount of the alkaline carbonate is 1% to 40% of the molar amount of calcium carbide in the calcium carbide, for example, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%. More preferably, it is 30% to 40%.

[0025] In some embodiments, the ratio of calcium carbide to organic solvent is 1g:(5~25)mL, for example 1g:5mL, 1g:6mL, 1g:7mL, 1g:8mL, 1g:9mL, 1g:10mL, 1g:11mL, 1g:12mL, 1g:13mL, 1g:14mL, 1g:15mL, 1g:16mL, 1g:17mL, 1g:18mL, 1g:19mL, 1g:20mL, 1g:21mL, 1g:22mL, 1g:23mL, 1g:24mL, 1g:25mL.

[0026] In some embodiments, the formaldehyde and water are fed in the form of a 30 wt.% to 40 wt.% formaldehyde aqueous solution. More preferably, the formaldehyde and water are fed in the form of a 35 wt.% to 40 wt.% formaldehyde aqueous solution.

[0027] In some preferred embodiments, when the water is added alone, the ratio of calcium carbide to water is 1g:0.1~1mL, for example 1g:0.1 mL, 1g:0.2 mL, 1g:0.3 mL, 1g:0.4 mL, 1g:0.5 mL, 1g:0.6 mL, 1g:0.7 mL, 1g:0.8 mL, 1g:0.9 mL or 1g:1 mL.

[0028] In some embodiments, the formaldehyde aqueous solution or water is preferably added dropwise. More preferably, the dropping time is controlled to not exceed 30 minutes.

[0029] By adopting the above technical solution, the present invention has the following advantages compared with other processes: This invention synthesizes propynyl alcohol by directly reacting calcium carbide with formaldehyde in a selected special catalytic and reaction system. The propynyl alcohol synthesis method of this invention can generate propynyl alcohol with high selectivity under mild reaction conditions.

[0030] Compared to traditional synthesis methods, the propynyl alcohol synthesis method of this invention uses a more readily available and cheaper catalyst, requires less sophisticated equipment, and is simpler to operate, enabling the preparation of propynyl alcohol at a lower cost and higher efficiency. Furthermore, the propynyl alcohol synthesis method of this invention is safe, with no large amounts of gas escaping, and is carried out under normal pressure, eliminating the need for specially sealed reaction vessels. The propynyl alcohol synthesis method of this invention is more suitable for industrial-scale production of propynyl alcohol, offering greater economic benefits. Detailed Implementation

[0031] To simplify the synthesis of propargyl alcohol and improve its economic efficiency, the inventors of this application have developed a method for directly synthesizing propargyl alcohol from calcium carbide in the same reaction system with water and formaldehyde. To ensure a smooth, mild, and highly selective reaction, the inventors conducted extensive research and experimental verification on the reaction system and conditions, including the selection and optimization of catalysts and their corresponding alkaline substances, the selection and optimization of solvents, and the screening and optimization of reaction conditions. Ultimately, the above reaction was achieved under specific catalytic and reaction systems. Further optimization resulted in a more selective reaction under milder conditions, while simultaneously considering synthesis cost, propargyl alcohol yield, and safety, achieving higher economic efficiency and making it more suitable for industrial production. Furthermore, subsequent testing and verification revealed that this invention has few side reactions, and the subsequent separation and purification process for propargyl alcohol is simple; high-purity propargyl alcohol can be obtained through distillation, thereby further reducing the overall production cost and energy consumption for large-scale propargyl alcohol production.

[0032] Specifically, the method for synthesizing propynyl alcohol provided by the present invention is as follows: calcium carbide, formaldehyde and / or polyoxymethylene react with water in an organic solvent in the presence of a catalyst and an alkaline carbonate to obtain propynyl alcohol, wherein the catalyst includes a quaternary ammonium salt catalyst and / or a cesium carbonate catalyst, and the organic solvent includes dimethyl sulfoxide.

[0033] Preferably, the organic solvent further includes 1,2-dichloroethane, 1,2-dibromoethane, dimethyl sulfoxide, and... N,N -Dimethylformamide, N One or a mixture of two or more of the following: methylpyrrolidone, ethanol, methanol, isopropanol, ethyl acetate, tetrahydrofuran, dioxane, acetone, acetonitrile, and toluene.

[0034] Preferably, the alkaline carbonate includes potassium and / or sodium salts.

[0035] Preferably, the molar ratio of the catalyst to the alkaline carbonate is 1:(0.1~10).

[0036] Preferably, the reaction temperature of the present invention is higher than room temperature. The most preferred reaction temperature of the present invention is 40~60℃.

[0037] The following will provide a further explanation of the technical solution, its implementation process, and its principles.

[0038] The present invention will be further described below with reference to embodiments. However, the present invention is not limited to the following embodiments. The implementation conditions used in the embodiments can be further adjusted according to different requirements of specific applications, and the implementation conditions not specified are conventional conditions in the industry. The technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

[0039] In the following embodiments, various processes and methods not described in detail are conventional methods known in the art.

[0040] In the following examples and comparative examples, the room temperature is 25±5℃.

[0041] Unless otherwise specified, the raw materials, reagents, containers and equipment used in the following examples and comparative examples are all commonly used raw materials, reagents and experimental equipment in the art and are obtained commercially.

[0042] In the following examples and comparative examples, the calcium carbide purity (CaC2 content) used was 74%.

[0043] Example 1: This example provides a method for synthesizing propynyl alcohol, as detailed below: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), sodium carbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) dropwise to the reaction flask at room temperature using a micro-injector. The dropwise addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0044] Acetonitrile (1.0 mmol) was added to the reaction solution as an internal standard for NMR. After mixing thoroughly, 100 μL of the mixture was added to an NMR tube, diluted with deuterated chloroform (0.5 mL), and sent for NMR detection of the proton NMR spectrum. The parameters were set as follows: number of scans (NS): ≥64; relaxation delay (D1): ≥15 seconds; spectral width (SW): 12 ppm; center frequency (O1P): 4.0 ppm. The integrated areas of the acetonitrile characteristic peak (δ 2.10 ppm) and the propynyl alcohol characteristic peak (-CH2 δ 4.0~4.1 ppm doublet) were recorded. The yield was calculated using the formula:

[0045] in, I The integral area is obtained directly from the NMR spectrum; N The number of hydrogen atoms in the characteristic peak. .

[0046] According to NMR detection, the yield of propargyl alcohol in this embodiment is 45%.

[0047] Example 2: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0048] The yield of propargyl alcohol in this example was determined to be 56% using the NMR detection method of Example 1.

[0049] Example 3: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), sodium bicarbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing thoroughly, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask using a micro-injector at room temperature. The addition time is about 5 min. Heat to 60 °C and keep the reaction at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0050] The yield of propargyl alcohol in this example was determined to be 34% by the NMR detection method of Example 1.

[0051] Example 4: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add paraformaldehyde (which can depolymerize into 1 mmol formaldehyde) and water (70 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0052] The yield of propargyl alcohol in this example was determined to be 47% using the NMR detection method of Example 1.

[0053] Example 5: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. React at room temperature for 18 hours.

[0054] The yield of propargyl alcohol in this example was determined to be 32% by the NMR detection method of Example 1.

[0055] Example 6: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. Heat to 40 °C and keep at 40 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0056] The yield of propargyl alcohol in this example was determined to be 52% using the NMR detection method of Example 1.

[0057] Example 7: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. Heat to 80 °C and keep at 80 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0058] The yield of propargyl alcohol in this example was determined to be 39% by the NMR detection method of Example 1.

[0059] Example 8: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), dimethyl sulfoxide (1 mL), and tetrahydrofuran (1 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0060] The yield of propargyl alcohol in this example was determined to be 65% by the NMR detection method of Example 1.

[0061] Example 9: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), dimethyl sulfoxide (1 mL), and N,N-dimethylformamide (1 mL) to the reaction flask in sequence. After mixing thoroughly, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask using a micro-injector at room temperature. The addition time is about 5 min. Heat to 60 °C and keep the reaction at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0062] The yield of propargyl alcohol in this example was determined to be 47% using the NMR detection method of Example 1.

[0063] Example 10: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.5 mmol), potassium carbonate (0.4 mmol), dimethyl sulfoxide (1 mL), and tetrahydrofuran (1 mL) to the reaction flask in sequence. After mixing thoroughly, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask using a micro-injector at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0064] The yield of propargyl alcohol in this example was determined to be 58% using the NMR detection method of Example 1.

[0065] Example 11: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.1 mmol), dimethyl sulfoxide (1 mL), and tetrahydrofuran (1 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature using a micro-injector. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0066] The yield of propargyl alcohol in this example was determined to be 55% using the NMR detection method of Example 1.

[0067] Example 12: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (1 mmol), dimethyl sulfoxide (1 mL), and N,N-dimethylformamide (1 mL) to the reaction flask in sequence. After mixing thoroughly, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask using a micro-injector at room temperature. The addition time is about 5 min. Heat to 60 °C and keep the reaction at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0068] The yield of propargyl alcohol in this example was determined to be 62% using the NMR detection method of Example 1.

[0069] Example 13: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), cesium carbonate (0.1 mmol), potassium carbonate (1 mmol), dimethyl sulfoxide (1 mL), and tetrahydrofuran (1 mL) to the reaction flask in sequence. After mixing thoroughly, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask using a micro-injector at room temperature. The addition time is about 5 min. Heat to 60 °C and keep the reaction at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0070] The yield of propargyl alcohol in this example was determined to be 64% using the NMR detection method of Example 1.

[0071] Example 14: This example provides another method for synthesizing propynyl alcohol, as follows: Add calcium carbide (containing 3 mol CaC2), tetrabutylammonium fluoride (0.3 mol), potassium carbonate (1.2 mol), dimethyl sulfoxide (2.0 L), and tetrahydrofuran (2.0 L) to the reaction flask in sequence. After mixing evenly, heat to 60°C and maintain the temperature at 60°C. Then, use a peristaltic pump to add formaldehyde aqueous solution (37 wt.% aqueous solution, 0.14 L) dropwise to the reaction flask over 30 min. After the addition is complete, continue to maintain the temperature at 60°C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0072] The yield of propargyl alcohol in this example was determined to be 70% by the NMR detection method of Example 1.

[0073] Comparative Example 1: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2) and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0074] The NMR detection method described in Example 1 was used for detection, and propynyl alcohol was not detected.

[0075] Comparative Example 2: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium bromide (0.1 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0076] The yield of propargyl alcohol in this example was determined to be 4.5% using the NMR detection method of Example 1.

[0077] Comparative Example 3: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetramethylammonium fluoride (0.1 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0078] The yield of propargyl alcohol in this example was determined to be 16% using the NMR detection method of Example 1.

[0079] Comparative Example 4: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0080] The yield of propargyl alcohol in this example was determined to be 20% using the NMR detection method of Example 1.

[0081] Comparative Example 5: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), 1,4-diazabicyclo[2.2.2]octane (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0082] The yield of propargyl alcohol in this example was determined to be 18% using the NMR detection method of Example 1.

[0083] Comparative Example 6: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), 1,8-diazabicyclo[5.4.0]undec-7-ene (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0084] The yield of propargyl alcohol in this example was determined to be 15% using the NMR detection method of Example 1.

[0085] Comparative Example 7: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), triethylamine (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0086] The yield of propargyl alcohol in this example was determined to be 22% using the NMR detection method of Example 1.

[0087] Comparative Example 8: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium hydroxide (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0088] The yield of propargyl alcohol in this example was determined to be 18% using the NMR detection method of Example 1.

[0089] Comparative Example 9: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), sodium hydroxide (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0090] The yield of propargyl alcohol in this example was determined to be 20% using the NMR detection method of Example 1.

[0091] Comparative Example 10: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), disodium hydrogen phosphate (0.4 mmol), and dimethyl sulfoxide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0092] The yield of propargyl alcohol in this example was determined to be 24% using the NMR detection method of Example 1.

[0093] Comparative Example 11: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and tetrahydrofuran (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0094] The yield of propargyl alcohol in this example was determined to be 22% using the NMR detection method of Example 1.

[0095] Comparative Example 12: Add calcium carbide (0.13 g, containing 1.5 mmol CaC2), tetrabutylammonium fluoride (0.1 mmol), potassium carbonate (0.4 mmol), and N,N-dimethylformamide (2 mL) to the reaction flask in sequence. After mixing well, add formaldehyde aqueous solution (37 wt.% aqueous solution, 75 μL) to the reaction flask at room temperature. The addition time is about 5 min. Heat to 60 °C and keep at 60 °C for 18 hours. After the reaction is completed, cool the reaction solution to room temperature.

[0096] The yield of propargyl alcohol in this example was determined to be 26% using the NMR detection method of Example 1.

[0097] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. A method for synthesizing propynyl alcohol, characterized in that, Calcium carbide, formaldehyde, and / or polyoxymethylene react with water in an organic solvent in the presence of a catalyst and alkaline carbonate to yield propynyl alcohol. The catalyst includes quaternary ammonium salt catalysts and / or cesium carbonate catalysts. The organic solvent includes dimethyl sulfoxide.

2. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The quaternary ammonium salt catalyst includes one or more of tetraalkylammonium fluoride catalyst, tetraalkylammonium chloride catalyst, tetraalkylammonium bromide catalyst, and tetraalkylammonium acetate catalyst; And / or, the alkaline carbonates include potassium and / or sodium salts; And / or, the molar ratio of the catalyst to the alkaline carbonate is 1:(0.1~10).

3. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The quaternary ammonium salt catalyst includes one or more of tetramethylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, tetramethylammonium bromide, tetraethylammonium bromide, tetrabutylammonium bromide, tetramethylammonium fluoride, tetraethylammonium fluoride, tetrabutylammonium fluoride, tetramethylammonium acetate, tetraethylammonium acetate, and tetrabutylammonium acetate. And / or, the alkaline carbonate includes one or more of sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate.

4. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The organic solvent may also selectively include tetrahydrofuran, N,N -Dimethylformamide, N One or more of the following: methylpyrrolidone, 1,2-dichloroethane, 1,2-dibromoethane, ethanol, methanol, isopropanol, ethyl acetate, dioxane, acetone, acetonitrile, and toluene; The dimethyl sulfoxide accounts for 40 wt.% to 100 wt.% of the organic solvent.

5. The method for synthesizing propynyl alcohol according to claim 4, characterized in that, The organic solvent also includes tetrahydrofuran, N,N -Dimethylformamide, N One or more of methylpyrrolidone; And / or, the dimethyl sulfoxide accounts for 40 wt.% to 80 wt.% of the organic solvent.

6. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The reaction temperature is 20℃~90℃.

7. The method for synthesizing propynyl alcohol according to claim 4, characterized in that, The reaction temperature is 35℃~80℃.

8. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The purity of the calcium carbide is 70%~100%; And / or, the degree of polymerization of the paraformaldehyde is 5 to 100.

9. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The molar ratio of calcium carbide in the calcium carbide to formaldehyde in the reaction system is 1:(0.5~3), and the formaldehyde in the reaction system includes formaldehyde directly fed into the feed and formaldehyde depolymerized from the polyoxymethylene. And / or, based on the molar amount of calcium carbide in the calcium carbide, the molar amount of the catalyst fed is 1% to 20% of the molar amount of calcium carbide; And / or, based on the molar amount of calcium carbide in the calcium carbide, the molar amount of the alkaline carbonate fed is 1% to 40% of the molar amount of calcium carbide; And / or, the ratio of calcium carbide to organic solvent is 1 g: (5~25) mL.

10. The method for synthesizing propynyl alcohol according to claim 1, characterized in that, The formaldehyde and water are added in the form of a 30 wt.%~40 wt.% formaldehyde aqueous solution; And / or, when the water is added alone, the ratio of calcium carbide to water is 1g:0.1~1mL.

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