A thioimidazolidinone compound based on a microwave-assisted method, and a preparation method and application thereof

Abstract

The application discloses a thioimidazolidinone compound based on a microwave-assisted method and a preparation method and application thereof, and belongs to the technical field of compound preparation. The application solves the problems of the traditional synthesis method of the thioimidazolidinone compound, such as the use of toxic solvents, low yield, long time, and many by-products. The application uses alpha-amino acid as raw material, uses water as solvent, uses the thermal effect induced by the microwave field to shorten the reaction time from several hours to minutes, successfully synthesizes the thioimidazolidinone compound, and uses phase transfer catalyst to improve the reaction rate and yield. The application avoids the use of toxic solvents such as DMF, reduces the reaction time, and the product yield is more than 95%. In addition, the thioimidazolidinone compound can be used as a corrosion inhibitor alone, and can be used in combination with a surfactant and / or a synergist, and has excellent corrosion inhibition effect; the thioimidazolidinone compound can also be used in the fields of medicine, pesticide, material synthesis and fine chemical industry, and has wide application scenarios.

Description

Technical Field

[0001] This invention belongs to the field of compound preparation technology, specifically relating to a microwave-assisted method for preparing a thioimidazolidine ketone compound and its application. Background Technology

[0002] Thioimidazolium compounds possess unique chemical properties and biological activities, making them important in pharmaceutical synthesis, pesticide preparation, materials synthesis, and fine chemical industries. Furthermore, these compounds exhibit excellent corrosion inhibition properties, making them suitable for the protection of industrial metals. Therefore, the synthesis of thioimidazolium compounds is becoming increasingly important.

[0003] However, existing methods for synthesizing thioimidazolidine ketones mostly rely on traditional thermodynamic reaction systems, typically using high-boiling-point organic solvents (such as DMF and DMSO) as the medium. These methods involve reaction times ranging from several hours to tens of hours, and generate numerous byproducts, leading to complex product separation and purification steps and low yields. Furthermore, current processes often involve toxic reagents or high-temperature, high-pressure conditions, resulting in high energy consumption, poor operational safety, and insufficient environmental friendliness. Moreover, the current preparation methods, due to varying degrees of defects such as numerous byproducts and low yields, limit the application and scope of these compounds. Therefore, there is an urgent need to develop a mild, simple, high-yield, environmentally friendly method for synthesizing thioimidazolidine ketones that does not use toxic or hazardous raw materials. This would fully realize the potential application value of these compounds and is of great significance for improving their preparation efficiency, application effectiveness, and expanding their application range. Summary of the Invention

[0004] In order to solve the above-mentioned problems in the prior art, the present invention provides a microwave-assisted method for preparing thioimidazolidine ketone compounds and their applications.

[0005] The technical solution of this invention:

[0006] One objective of this invention is to provide a microwave-assisted method for preparing thioimidazolidine ketone compounds. The method involves dissolving α-amino acids and a phase transfer catalyst in a solvent, stirring to form a homogeneous solution, adding an alkaline catalyst to the homogeneous solution, continuing stirring, adding an isothiocyanate compound after stirring, and then performing a microwave-assisted reaction. After the reaction is completed, the mixture is cooled to room temperature, and the product is subjected to acidification, washing, filtration, and recrystallization steps in sequence to obtain the thioimidazolidine ketone compound.

[0007] Further specifying, the phase transfer catalyst is a quaternary ammonium salt phase transfer catalyst or a non-ionic phase transfer catalyst.

[0008] Further specifying, the solvent is water.

[0009] Further specifying, the alkaline catalyst is an organic weak base, and the isothiocyanate compound is an alkyl isothiocyanate or an aryl isothiocyanate.

[0010] To further specify, organic weak bases are amine compounds that have a deprotonating effect.

[0011] Further specified, the molar ratio of α-amino acid to isothiocyanate compound is 1:(0.83~1.20).

[0012] Further specified, the amount of alkaline catalyst used is (0.5 to 1.2) times the sum of α-amino acids and isothiocyanate compounds.

[0013] Further specifying, the molar-volume ratio of the sum of α-amino acids and isothiocyanate compounds to the solvent is 1 mol: (2500-3000) mL.

[0014] Further specifying, the amount of phase transfer catalyst used is 5% to 20% of the total mass of α-amino acid, isothiocyanate compound and basic catalyst.

[0015] Further specifying the process parameters for the microwave-assisted reaction: power not exceeding 1000W, temperature 40–80℃, and reaction time 3–15 min.

[0016] A second objective of this invention is to provide a thioimidazolone compound prepared using the above-described method.

[0017] A third objective of this invention is to provide an application of the above-mentioned thioimidazolium ketone compound, specifically, the thioimidazolium ketone compound is used alone as a corrosion inhibitor or as a corrosion inhibitor component in the formulation of a compound corrosion inhibitor.

[0018] The fourth objective of this invention is to provide an application of the above-mentioned thioimidazolone compound, specifically, the thioimidazolone compound is used in pharmaceutical synthesis, pesticide preparation, and fine chemical industries.

[0019] The fifth objective of this invention is to provide a compound corrosion inhibitor, the chemical composition of which, by weight percentage, comprises: 50-90% of the thioimidazolium ketone compound obtained by the above preparation method, 10-40% of the surfactant, and 0-10% of the synergist.

[0020] Further specifying, the surfactant is a nonionic surfactant or anionic surfactant.

[0021] Furthermore, the synergist is a thiolated small molecule derivative.

[0022] The beneficial effects of this invention are:

[0023] (1) This invention uses α-amino acids as raw materials and water as solvent to synthesize thioimidazolone compounds by microwave-assisted method. During the synthesis process, a phase transfer catalyst is used to improve the reaction rate and yield.

[0024] (2) The method provided by the present invention successfully synthesizes thioimidazolidine ketone compounds under the condition of water as solvent, avoiding the use of toxic solvents such as DMF. Furthermore, the reaction time is shortened from several hours to minutes by utilizing the thermal effect induced by microwave field, which greatly reduces the reaction time. In addition, the product synthesized by the present invention has high purity, almost no by-products, and a yield of over 95%. It is a green, simple, and efficient synthesis method.

[0025] (3) The thioimidazolidine ketone compounds synthesized in this invention have expanded their applications in multiple fields due to their high yield, high purity, and short synthesis time. In the pharmaceutical field, these compounds can be used for the development of antibacterial, anti-inflammatory, and antitumor drugs; in the pesticide field, they can be used as plant protectants or fungicides; and in the fine chemical field, they play an important role in the synthesis processes of organocatalysis and dye synthesis. Furthermore, the thioimidazolidine ketone compounds of this invention can be used alone as corrosion inhibitors or in combination with surfactants and / or synergistic agents.

[0026] (4) The thioimidazolium ketone compound synthesized in this invention contains multiple electron-rich functional groups, such as sulfur (S), nitrogen (N), and carbonyl oxygen (O). The thiocarbonyl group (C=S) in the structure and the sulfur- or nitrogen-containing substituents in the amino acid side chain can act as metalophilic electron donors, forming a stable coordination adsorption layer with the metal surface. The two nitrogen atoms in the imidazolium ring structure also have strong coordination ability, which helps to enhance the binding strength between the thioimidazolium ketone compound and the metal surface. In addition, the thioimidazolium ketone compound synthesized in this invention retains some hydrophilic groups (–OH, –COOH, –NH2) or hydrophobic groups (alkyl, aryl) in the amino acid molecule structure, so that the compound has both polar effects to enhance adsorption and can form a certain hydrophobic barrier during adsorption, effectively isolating the metal surface from the corrosion of water and corrosive ions. When the isothiocyanate compound used in this invention is an aryl isothiocyanate, the synthesized thioimidazolium ketone compound contains aromatic substituents. This type of aromatic ring structure can enhance the density and stability of the adsorption film formed by the thioimidazolium ketone compound on the metal surface through π-π interactions. In summary, the thioimidazolium ketone compound of this invention forms a dense, stable, and hydrophobic organic protective film on the metal surface through a synergistic mechanism of chemisorption and physisorption, thereby significantly inhibiting corrosion reactions.

[0027] (5) When the thioimidazolidine ketone compound of the present invention is used in combination with a surfactant, the surfactant can significantly reduce the surface tension of the metal, enhance the diffusion rate and adsorption uniformity of the compounded corrosion inhibitor on the metal surface, thereby accelerating the formation of a dense corrosion-inhibiting film. The hydrophobic segments of the surfactant can also be further arranged on the outside of the adsorption layer, enhancing the hydrophobicity and stability of the entire film. On the other hand, when the compounded corrosion inhibitor of the present invention contains a synergist, the synergist contains multiple sulfur atoms and amino groups, with a concentrated electron cloud density, which can form a strong coordination adsorption with the metal surface, and form a composite adsorption structure with the thioimidazolidine ketone compound through hydrogen bonding, electrostatic interaction or intermolecular interaction, thereby improving the density, coverage and mechanical stability of the film, and thus improving the corrosion inhibition efficiency of the corrosion inhibitor. Attached Figure Description

[0028] Figure 1 The impedance curves of N80 carbon steel are shown in the examples 3-8, with and without the corrosion inhibitor.

[0029] Figure 2 The NMR spectrum of the MTEPI synthesized in Example 1 is shown below. 1 H NMR);

[0030] Figure 3 The infrared spectrum of the MTEPI synthesized in Example 1 is shown. Detailed Implementation

[0031] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0032] Many 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 different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0033] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0034] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0035] The microwave reactor used in the following examples is a high-voltage ultrasonic microwave combined workstation XH-300PE.

[0036] Example 1

[0037] In this embodiment, the thioimidazolidine ketone compound 5-(2-(methylthio)ethyl)-3-phenyl-2-thioimidazolidine-4-one (MTEPI) was synthesized via the following route:

[0038]

[0039] (1) Dissolve 1.5g of L-methionine and 0.73g of phase transfer catalyst hexadecyltrimethylammonium bromide (CTAB) in water and stir to form a homogeneous solution. Add 2g of basic catalyst triethylamine to the homogeneous solution and continue stirring for 5 minutes. Then slowly add 1.36g of phenyl isothiocyanate and stir. Place the reaction system in a microwave reactor, set the power to 1000W, the temperature to 60℃, and the reaction time to 5 minutes.

[0040] (2) After the reaction is complete, cool the system to room temperature, add 15-20 mL of 1 mol / L hydrochloric acid for acidification until a precipitate is formed in the system. At this time, pH=6. Filter the precipitate to obtain the crude product, and wash it with deionized water.

[0041] (3) Collect the crude product after washing, dissolve it in hot ethanol and stir until the crude product is completely dissolved. Cool the solution at room temperature and then refrigerate it. After white needle-like or slightly yellow needle-like crystals are formed, filter the solution to obtain the first recrystallization product. Recrystallize twice in total to obtain MTEPI with a yield of more than 95%.

[0042] The nuclear magnetic resonance of the MTEPI synthesized in this embodiment 1 H NMR such as Figure 2 As shown: 1 H NMR (400MHz, Chloroform-d) δ8.51 (brs, 1H), 7.50 (m, 3H), 7.36-7.30 (m, 2H), 4 .43 (m, 1H), 2.69 (t, J=6.8Hz, 2H), 2.31 (m, 1H), 2.20-2.13 (m, 1H), 2.10 (s, 3H).

[0043] The infrared spectrum of the MTEPI synthesized in this embodiment is as follows: Figure 3 As shown in the figure, 3169.84cm -1 A moderate absorption peak appears at 2985.77 cm⁻¹, corresponding to the N–H stretching vibration in the imidazolidinone structure, indicating that the compound contains an amine group; -1 and 2911.86cm -1The peak at 1748.77 cm⁻¹ corresponds to the CH stretching vibrations in the -CH₃ and -CH₂- groups of the methylthioethyl side chain; -1 A strong absorption peak was observed at 1524.7 cm⁻¹, corresponding to the carbonyl (C=O) stretching vibration, indicating the presence of an imidazolidine-4-one structure; -1 and 1595.39cm -1 The absorption peak is a characteristic peak of the C=C stretching vibration of the aromatic ring, indicating the presence of a phenyl structure in the compound molecule; 1410.21 cm⁻¹ -1 1355.52cm -1 and 1340.33cm -1 The absorption peaks are attributed to the stretching vibrations of the CN bonds in the heterocyclic structure, and typically appear at 1300-1500 cm⁻¹. -1 Within the range; furthermore, at 1206.74cm -1 The absorption peak appearing at this point corresponds to the stretching vibration of the C=S bond. In the low wavenumber region, such as 786.20 cm⁻¹... -1 744.79cm -1 708.71cm -1 and 692.59cm -1 The absorption peaks represent the out-of-plane bending vibrations of the C–H atoms on the aromatic ring. Infrared spectroscopy results show that the positions of the infrared absorption peaks in this compound are highly consistent with the structure of 5-(2-(methylthio)ethyl)-3-phenyl-2-thioimidazolidine-4-one, indicating the successful synthesis of MTEPI.

[0044] Comparative Example 1

[0045] (1) Dissolve 1.5g of L-methionine and 2g of triethylamine in 50mL of solvent consisting of N,N-dimethylformamide (DMF) and water (DMF:water = 8:2, v / v), then add 1.36g of phenyl isothiocyanate to the solution, stir the reaction system at room temperature for 6h, and monitor the reaction progress by thin-layer chromatography (TLC, ethyl acetate / hexane = 30% or methanol / chloroform = 5-10%) until the reaction is complete;

[0046] (2) After the reaction is complete, cool the system to room temperature and add 200-250 mL of 1 mol / L hydrochloric acid for acidification until a precipitate is formed in the system. At this point, the pH is 1. Filter the precipitate to obtain the crude product and wash it with deionized water.

[0047] (3) The operation process and parameter settings in this step are the same as in (3) of Example 1, and MTEPI is obtained with a yield of 70%.

[0048] Example 2

[0049] In this embodiment, a thioimidazolidine ketone compound (5-(mercaptomethyl)-3-phenyl-2-thioimidazolidine-4-one) was synthesized via the following route:

[0050]

[0051] The difference between this embodiment and Example 1 is that the synthesized thioimidazolidine ketone compound is (5-(mercaptomethyl)-3-phenyl-2-thioimidazolidine-4-one), the amino acid used in (1) is L-cysteine, the amount of which is 1.2g, the amount of phase transfer catalyst hexadecyltrimethylammonium bromide (CTAB) is 0.68g, and the remaining process steps and parameter settings are the same as in Example 1.

[0052] The yield in this embodiment is greater than 95%.

[0053] Comparative Example 2

[0054] (1) Dissolve 1.2 g of L-cysteine ​​and 2 g of triethylamine in 50 mL of solvent consisting of N,N-dimethylformamide (DMF) and water (DMF:water = 8:2, v / v), then add 1.36 g of phenyl isothiocyanate to the solution, stir the reaction system at room temperature for 10 h, and monitor the reaction progress by thin-layer chromatography (TLC, ethyl acetate / hexane = 30% or methanol / chloroform = 5-10%) until the reaction is complete;

[0055] (2) After the reaction is complete, cool the system to room temperature and add 200-250 mL of 1 mol / L hydrochloric acid for acidification until a precipitate is formed in the system. At this point, the pH is 1. Filter the precipitate to obtain the crude product and wash it with deionized water.

[0056] (3) The operation process and parameter settings in this step are the same as those in (3) of Example 1, and (5-(mercaptomethyl)-3-phenyl-2-thioimidazolidine-4-one) is obtained with a yield of 75%.

[0057] In both Comparative Examples 1 and 2, the solvent used was a solution composed of DMF and water. DMF was used in both examples, and its long-term use poses potential hazards to human health and the environment, making the traditional synthesis method environmentally unfriendly. Furthermore, the reaction time in Comparative Example 1 was as long as 6 hours, and in Comparative Example 2 as long as 10 hours, several times longer than in Example 1. This prolonged reaction time increased the energy consumption in the preparation of the thioimidazolidineone compound. Additionally, during hydrochloric acid acidification, Comparative Examples 1 and 2 required large amounts of hydrochloric acid to precipitate the precipitate, increasing not only the preparation cost but also potential pollution and safety risks. Examples 1 and 2, on the other hand, only required small amounts of hydrochloric acid to precipitate the precipitate. Moreover, the yields in Comparative Examples 1 and 2 were low, with yields of 70% and 75% respectively after two recrystallizations with anhydrous ethanol.

[0058] Example 3

[0059] Using MTEPI obtained in Example 1 as a corrosion inhibitor, the corrosion performance of the corrosion inhibitor was tested in a carbon dioxide corrosion system.

[0060] Example 4

[0061] Using MTEPI obtained in Example 1 as one of the components, it was compounded with the nonionic surfactant fatty alcohol polyoxyethylene ether (AEO) to obtain a compound corrosion inhibitor. The chemical composition of the corrosion inhibitor, by weight percentage, includes: 70% MTEPI obtained in Example 1 and 30% AEO. The corrosion performance of the compound corrosion inhibitor was tested in a carbon dioxide corrosion system.

[0062] Example 5

[0063] Using MTEPI obtained in Example 1 as one of the components, it was compounded with the anionic surfactant sodium dodecylbenzenesulfonate (SDBS) to obtain a compound corrosion inhibitor. The chemical composition of the corrosion inhibitor, by weight percentage, includes: 70% MTEPI obtained in Example 1 and 30% SDBS. The corrosion performance of the compound corrosion inhibitor was tested in a carbon dioxide corrosion system.

[0064] Example 6

[0065] Using MTEPI obtained in Example 1 as one of the components, it was compounded with the nonionic surfactant fatty alcohol polyoxyethylene ether (AEO) and the synergist thiourea (TU) to obtain a compound corrosion inhibitor. The chemical composition of the corrosion inhibitor, by weight percentage, includes: 72% MTEPI obtained in Example 1, 18% AEO, and 10% TU. The corrosion performance of the compound corrosion inhibitor was tested in a carbon dioxide corrosion system.

[0066] Example 7

[0067] Using MTEPI obtained in Example 1 as one of the components, a compound corrosion inhibitor was prepared by combining it with the nonionic surfactant fatty alcohol polyoxyethylene ether (AEO) and the synergist 2-mercaptobenzimidazole (MBI). The chemical composition of this corrosion inhibitor, by weight percentage, consisted of: 72% MTEPI obtained in Example 1, 18% AEO, and 10% MBI. The corrosion performance of this compound corrosion inhibitor was tested in a carbon dioxide corrosion system.

[0068] Example 8

[0069] Using MTEPI obtained in Example 1 as one of the components, it was compounded with the nonionic surfactant fatty alcohol polyoxyethylene ether (AEO), the synergist 2-mercaptobenzimidazole (MBI), and thiourea (TU) to obtain a compound corrosion inhibitor. The chemical composition of this corrosion inhibitor, by weight percentage, includes: 72% MTEPI obtained in Example 1, 18% AEO, 5% MBI, and 5% TU. The corrosion performance of this compound corrosion inhibitor was tested in a carbon dioxide corrosion system.

[0070] The corrosion performance of the corrosion inhibitors in Examples 3-8 was tested in a carbon dioxide corrosion system:

[0071] Using N80 carbon steel as the test material, it was polished with 400, 800, 1000 and 1500 grit silicon carbide sandpaper in sequence, rinsed with acetone and anhydrous ethanol in sequence, and then dried with hot air for later use.

[0072] The test used a brine solution simulating an oilfield environment. The brine solution formula was: NaCl 2.587 g / L, NaHCO3 1.740 g / L, CaCl2 0.323 g / L, and MgCl2 0.070 g / L. Eleven brine solutions (each 1 L in volume) were prepared, with the first serving as a blank control group without added corrosion inhibitor. High-purity N2 was bubbled into each of the eleven brine solutions for 2 hours to ensure complete O2 removal, followed by bubbling CO2 into each solution for 2 hours to obtain a saturated carbon dioxide salt solution. The corrosion inhibitors from Examples 3-8 and the compound corrosion inhibitor were dissolved in anhydrous ethanol to prepare ethanol solutions. The amount of anhydrous ethanol used was small, intended to dissolve the corrosion inhibitors, and was negligible. Ethanol solutions prepared with MTEPI from Example 3 were added to saturated carbon dioxide salt solutions 2 to 6, with MTEPI concentrations of 10 ppm, 20 ppm, 50 ppm, 100 ppm, and 200 ppm, respectively (the MTEPI concentrations mentioned here refer to the amount of MTEPI to be added to the saturated carbon dioxide salt solution; for example, 100 ppm means that the total amount of MTEPI required in 1 L of saturated carbon dioxide salt solution is 0.1 g). Ethanol solutions prepared with compound corrosion inhibitors from Examples 4 to 8 were added to saturated carbon dioxide salt solutions 7 to 11, with compound corrosion inhibitor concentrations of 100 ppm in each case (the compound corrosion inhibitor concentrations mentioned here refer to the amount of compound corrosion inhibitor to be added to the saturated carbon dioxide salt solution; for example, 100 ppm means that the total amount of compound corrosion inhibitor required in 1 L of saturated carbon dioxide salt solution is 0.1 g), resulting in test solutions 1 to 11. Electrochemical impedance spectroscopy (EIS) tests were then performed on test solutions 1–11. CO2 was continuously introduced during both the addition of the corrosion inhibitor and the EIS tests to maintain the salt solution at saturation. The EIS test method was as follows: the experimental temperature was 60℃, and a Gamry 600+ workstation was used with a three-electrode system. The working electrode was N80 carbon steel, the reference electrode was a saturated calomel electrode (SCE), and the platinum electrode was used as the auxiliary electrode. The exposed area of ​​the N80 carbon steel electrode was 1 cm². 2 The test frequency ranged from 0.01Hz to 100kHz, with an AC voltage signal amplitude of 10mV. Impedance data were analyzed and fitted using Zsimpwin software. The corrosion inhibition efficiency η was [not specified in the original text]. z The result is obtained by calculation using equation (1):

[0073]

[0074] Among them, R p(inh) and R p(0) R represents the total resistance with and without corrosion inhibitor, respectively. f R represents the resistance of the corrosion inhibitor film formed on the surface of N80 carbon steel. ct R represents charge transfer resistance.p =R f +R ct The total resistance is given. The electrochemical impedance spectroscopy results are shown in Table 1.

[0075] Table 1. EIS test results of N80 carbon steel in saturated carbon dioxide salt solution with and without corrosion inhibitors from Examples 3-8.

[0076]

[0077] As can be seen from the data in Table 1, after adding the corrosion inhibitor, the corrosion inhibition efficiency η z The concentration of MTEPI significantly increased, indicating a markedly enhanced corrosion inhibition effect on N80 carbon steel. This demonstrates that in the carbon dioxide corrosion system, both the MTEPI from Example 1, used alone as a corrosion inhibitor and in combination with other substances, exhibit excellent corrosion resistance to N80 carbon steel within the range of 10–200 ppm. When MTEPI from Example 1 was used alone as a corrosion inhibitor, its corrosion inhibition efficiency increased significantly with increasing concentration. At the same concentration (100 ppm), combining MTEPI from Example 1 with a surfactant, and combining MTEPI with a surfactant and a synergist, also improved the corrosion inhibition efficiency. Electrochemical impedance spectroscopy confirmed that the corrosion inhibition performance of the combined inhibitor was superior to that of MTEPI alone.

[0078] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing thioimidazolidine ketone compounds based on microwave-assisted method, characterized in that, The method is as follows: α-amino acids and phase transfer catalysts are dissolved in a solvent and stirred to form a homogeneous solution. An alkaline catalyst is added to the homogeneous solution and stirring is continued. After stirring is completed, isothiocyanate compounds are added, followed by microwave-assisted reaction. After the reaction is completed, the mixture is cooled to room temperature, and the product is subjected to acidification, washing, filtration and recrystallization in sequence to obtain thioimidazolidine ketone compounds. The solvent is water; The process parameters for the microwave-assisted reaction are: power not exceeding 1000W, temperature 40~80°C, and reaction time 3~15min; The structures of thioimidazolidine ketone compounds are shown in Formula I or Formula II: Formula I Formula II; The phase transfer catalyst is a quaternary ammonium salt phase transfer catalyst or a non-ionic phase transfer catalyst; the basic catalyst is an organic weak base; the isothiocyanate compound is an alkyl isothiocyanate or an aryl isothiocyanate. The molar ratio of the α-amino acid to the isothiocyanate compound is 1:(0.83~1.20); the amount of basic catalyst is (0.5~1.2) equivalents of the sum of the α-amino acid and the isothiocyanate compound; the amount of phase transfer catalyst is 5~20% of the total mass of the α-amino acid, the isothiocyanate compound and the basic catalyst; the molar-volume ratio of the sum of the α-amino acid and the isothiocyanate compound to the solvent is 1 mol:(2500-3000) mL.

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