Method for preparing 4-chloro-5-(4-tolyl)-1H-imidazole-2-formonitrile

Abstract

The present disclosure relates to a process for the preparation of 4-chloro-5-(4-tolyl)-1H-imidazole-2-formonitrile. The methods of the present disclosure are performed under mild reaction conditions. Further, the method of the present disclosure is simple, cost effective and environmentally friendly, and provides 4-chloro-5-(4-tolyl)-1H-imidazole-2-formonitrile with relatively higher purity and higher yield.

Description

Technical Field

[0001] This disclosure relates to a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile. Background Technology

[0002] The background information described below relates to this disclosure but is not necessarily prior art.

[0003] 4-Chloro-5-(4-Tolyl)-1H-imidazol-2-carboxynitrile is a key intermediate in the synthesis of cyazofamid. The structure of 4-chloro-5-(4-Tolyl)-1H-imidazol-2-carboxynitrile is as follows: .

[0004] Cyazofamid is an important fungicide. Its chemical name is 4-chloro-2-cyano-N,N-dimethyl-5-(4-tolyl)-1H-imidazol-1-sulfonamide. The structure of cyazofamid is: .

[0005] Typically, the preparation of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is carried out in DMF in the presence of sodium bisulfite, followed by chlorination with N-chlorosuccinimide (NCS). N-chlorosuccinimide (NCS) is expensive, and the succinimide byproducts formed during the reaction require cumbersome post-treatment to remove them.

[0006] Furthermore, conventional methods for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylonitrile have drawbacks, such as harsh reaction conditions, long reaction times, low yields, the need for toxic, expensive, or unavailable reagents, impracticality, and operational limitations during synthesis. Therefore, conventional methods cannot provide an effective solution for the synthesis of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylonitrile.

[0007] Therefore, there is a need for a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile that overcomes the above-mentioned disadvantages or at least provides a useful alternative.

[0008] Purpose of the invention At least one embodiment described herein satisfies some of the objectives of this disclosure as follows: One object of this disclosure is to improve one or more problems of the prior art, or at least to provide a useful alternative.

[0009] Another object of this disclosure is to provide a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile.

[0010] Another object of this disclosure is to provide a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile with relatively higher purity and higher yield.

[0011] Another object of this disclosure is to provide a simple, efficient and cost-effective method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile.

[0012] Another object of this disclosure is to provide an environmentally friendly and commercially scalable method for the preparation of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile.

[0013] Other objects and advantages of this disclosure will become more apparent from the following description, which is not intended to limit the scope of this disclosure. Summary of the Invention

[0014] This disclosure relates to a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile (Formula I). ​​The method comprises: treating a compound of Formula II with a phosphorus halide in a first fluid medium under stirring at a first predetermined temperature for a first predetermined time period to obtain a mixture of compounds of Formula III and Formula IV; reducing the mixture of compounds of Formula III and Formula IV with a reducing agent in a second fluid medium under stirring at a second predetermined temperature for a second predetermined time period to obtain compound of Formula IV; and chlorinating compound of Formula IV with a chlorinating agent in a third fluid medium under stirring at a third predetermined temperature for a third predetermined time period to obtain 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile (Formula I).

[0015] In embodiments of this disclosure, the first fluid medium is selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, toluene, ethyl acetate, xylene, benzene, tetrahydrofuran, 1,4-dioxane, and combinations thereof.

[0016] In embodiments of this disclosure, the phosphorus halide is phosphorus trichloride.

[0017] In embodiments of this disclosure, the molar ratio of the compound of formula II to phosphorus halide is in the range of 1:1.5 to 1:5.

[0018] In embodiments of this disclosure, the first predetermined temperature is in the range of 20°C to 50°C.

[0019] In embodiments of this disclosure, the first predetermined time period is in the range of 5 hours to 24 hours.

[0020] In embodiments of this disclosure, the second fluid medium is selected from the group consisting of dimethylacetamide, dimethylformamide, sulfolane, dimethyl sulfoxide, N-methylpyrrolidone, acetonitrile, and combinations thereof.

[0021] In embodiments of this disclosure, the reducing agent is selected from the group consisting of sodium metabisulfite, sodium bisulfite, sodium sulfite, potassium bisulfite, potassium metabisulfite, potassium sulfite, potassium dithionite, sodium dithionite, and combinations thereof.

[0022] In embodiments of this disclosure, the second predetermined temperature is in the range of 60°C to 150°C.

[0023] In embodiments of this disclosure, the second predetermined time period is in the range of 2 to 10 hours.

[0024] In embodiments of this disclosure, the chlorinating agent is selected from the group consisting of sodium hypochlorite, phosphorus oxychloride, phosphorus pentachloride, sulfur chloride, and sulfur dichloride.

[0025] In embodiments of this disclosure, the third fluid medium is water.

[0026] In embodiments of this disclosure, the molar ratio of the compound of formula IV to the chlorinating agent is in the range of 1:1 to 1:15.

[0027] In embodiments of this disclosure, the third predetermined temperature is in the range of 20°C to 50°C.

[0028] In embodiments of this disclosure, the third predetermined time period is in the range of 2 to 10 hours.

[0029] In embodiments of this disclosure, the yield of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile is in the range of 65% to 80%.

[0030] 4-Chloro-5-(4-Tolyl)-1H-Imidazol-2-carboxynitrile was prepared according to the method of this disclosure.

[0031] In embodiments of this disclosure, the purity of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile is greater than 90%.

[0032] In embodiments of this disclosure, the purity of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile is in the range of 90% to 99%. Detailed Implementation

[0033] This disclosure relates to a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile.

[0034] This document now describes embodiments of the present disclosure. Embodiments are provided to thoroughly and completely convey the scope of this disclosure to those skilled in the art. Numerous details relating to particular components and methods are set forth to provide a complete understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that the details provided in the embodiments should not be construed as limiting the scope of the disclosure. In some embodiments, well-known methods, well-known apparatus structures, and well-known techniques are not described in detail.

[0035] The terminology used in this disclosure is for the purpose of explaining particular embodiments only and should not be construed as limiting the scope of this disclosure. As used herein, the forms “a,” “an,” and “the” may also be intended to include plural forms unless the context explicitly suggests otherwise. The terms “comprises,” “comprising,” “including,” and “having” are open-ended transitional phrases that describe the presence of the stated features, integers, steps, operations, elements, modules, units, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof. The specific order of steps disclosed in the methods and processes of this disclosure should not be construed as requiring them to be performed in the order stated or shown. It should also be understood that additional or alternative steps may be employed.

[0036] As used herein, the term “and / or” includes any and all combinations of one or more of the listed relevant elements.

[0037] The terms first, second, third, etc., should not be construed as limiting the scope of this disclosure, as these terms may be used only to distinguish one element, component, region, layer, or part from another. Terms such as first, second, third, etc., as used herein do not imply a particular order or sequence unless expressly implied in this disclosure.

[0038] Typically, the preparation of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is carried out in DMF in the presence of sodium bisulfite, followed by chlorination with N-chlorosuccinimide (NCS). N-chlorosuccinimide (NCS) is expensive, and the succinimide byproducts formed during the reaction require cumbersome post-treatment to remove them.

[0039] Furthermore, conventional methods for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylonitrile have drawbacks, such as harsh reaction conditions, long reaction times, low yields, the need for toxic, expensive, or unavailable reagents, impracticality, and operational limitations during synthesis. Therefore, conventional methods cannot provide an effective solution for the synthesis of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylonitrile.

[0040] This disclosure provides an improved method for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylonitrile. The structure of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylonitrile is shown in Formula I: .

[0041] The method disclosed herein is simple, environmentally friendly, and economical, and improves the yield and purity of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile.

[0042] According to this disclosure, a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile includes the following steps: a) In a first fluid medium, under stirring and at a first predetermined temperature, the compound of formula II is treated with phosphorus halide for a first predetermined time period to obtain a mixture of the compound of formula III and the compound of formula IV.

[0043] b) In a second fluid medium, under stirring and at a second predetermined temperature, a mixture of compounds of formula III and IV is reduced using a reducing agent for a second predetermined time period to obtain compound IV; and

[0044] c) In a third fluid medium, under stirring, at a third predetermined temperature, chlorinating compound IV with a chlorinating agent for a third predetermined time period, to obtain 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile (Formula I). .

[0045] In the first step, in a first fluid medium, under stirring and at a first predetermined temperature, a predetermined amount of compound II is treated with phosphorus halide for a first predetermined time period to obtain a mixture of compound III and compound IV.

[0046] In embodiments of this disclosure, the first fluid medium is selected from the group consisting of dichloromethane (DCM), chloroform, carbon tetrachloride, toluene, ethyl acetate, xylene, benzene, tetrahydrofuran, 1,4-dioxane, and combinations thereof. In an exemplary embodiment of this disclosure, the first fluid medium is dichloromethane.

[0047] In embodiments of this disclosure, the phosphorus halide is phosphorus trichloride.

[0048] In embodiments of this disclosure, the molar ratio of the compound of formula II to phosphorus halide is in the range of 1:1.5 to 1:5. In an exemplary embodiment of this disclosure, the molar ratio of the compound of formula II to phosphorus halide is 1:2.5.

[0049] In embodiments of this disclosure, the first predetermined temperature is in the range of 20°C to 50°C. In an exemplary embodiment of this disclosure, the first predetermined temperature is 30°C.

[0050] In embodiments of this disclosure, the first predetermined time period is in the range of 5 to 24 hours. In an exemplary embodiment of this disclosure, the first predetermined time period is 10 hours.

[0051] In the second step, in a second fluid medium, under stirring and at a second predetermined temperature, a mixture of compound III and compound IV is reduced using a reducing agent for a second predetermined time period to obtain compound IV.

[0052] In embodiments of this disclosure, the second fluid medium is selected from the group consisting of dimethylacetamide, dimethylformamide (DMF), sulfolane, dimethyl sulfoxide, N-methylpyrrolidone, acetonitrile, and combinations thereof. In an exemplary embodiment of this disclosure, the second fluid medium is dimethylformamide.

[0053] In embodiments of this disclosure, the reducing agent is selected from the group consisting of sodium metabisulfite, sodium bisulfite, sodium sulfite, potassium bisulfite, potassium metabisulfite, potassium sulfite, potassium dithionite, sodium dithionite, and combinations thereof. In an exemplary embodiment of this disclosure, the reducing agent is sodium metabisulfite.

[0054] In embodiments of this disclosure, the second predetermined temperature is in the range of 60°C to 150°C. In a preferred embodiment of this disclosure, the second predetermined temperature is 80°C to 100°C. In an exemplary embodiment of this disclosure, the second predetermined temperature is 90°C.

[0055] In embodiments of this disclosure, the second predetermined time period is in the range of 2 to 10 hours. In a preferred embodiment of this disclosure, the second predetermined time period is 4 to 6 hours. In an exemplary embodiment of this disclosure, the second predetermined time period is 5 hours.

[0056] In the third step, in a third fluid medium, under stirring and at a third predetermined temperature, the compound of formula IV is chlorinated with a chlorinating agent for a third predetermined time period to obtain 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile (formula I).

[0057] In embodiments of this disclosure, the chlorinating agent is selected from the group consisting of sodium hypochlorite, phosphorus oxychloride, phosphorus pentachloride, sulfur chloride, and sulfur dichloride. In an exemplary embodiment of this disclosure, the chlorinating agent is sodium hypochlorite.

[0058] In embodiments of this disclosure, the third fluid medium is water.

[0059] In embodiments of this disclosure, the molar ratio of the compound of formula IV to the chlorinating agent is in the range of 1:1 to 1:15. In an exemplary embodiment of this disclosure, the molar ratio of the compound of formula IV to the chlorinating agent is 1:1.5.

[0060] In embodiments of this disclosure, the third predetermined temperature is in the range of 20°C to 50°C. In an exemplary embodiment of this disclosure, the third predetermined temperature is 30°C.

[0061] In embodiments of this disclosure, the third predetermined time period is in the range of 2 to 10 hours. In an exemplary embodiment of this disclosure, the third predetermined time period is 5 hours.

[0062] According to the method of this disclosure, the yield of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is thus obtained in the range of 65% to 80%. In an exemplary embodiment of this disclosure, the yield of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is 68.58%.

[0063] 4-Chloro-5-(4-Tolyl)-1H-Imidazol-2-carboxynitrile was prepared according to the method of this disclosure.

[0064] According to the method of this disclosure, the purity of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile is greater than 90%.

[0065] According to the method of this disclosure, the purity of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is in the range of 90% to 99%. In an exemplary embodiment of this disclosure, the purity of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is 93%.

[0066] According to an exemplary embodiment of this disclosure, a schematic process for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile is shown in Scheme I below: .

[0067] Option I This disclosure provides a simple, environmentally friendly and economical method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxylonite with relatively higher yield and higher purity.

[0068] The foregoing description of the embodiments is provided for illustrative purposes and is not intended to limit the scope of this disclosure. Components of a particular embodiment are generally not limited to that particular embodiment and are interchangeable. Such changes should not be considered as departing from this disclosure, and all such modifications are considered to be within the scope of this disclosure.

[0069] The present disclosure is further described in conjunction with the following experiments, which are for illustrative purposes only and should not be construed as limiting the scope of the disclosure. These experiments can be scaled up to industrial / commercial scale, and the results can be extrapolated to industrial scale.

[0070] Experiment Details Example 1: Preparation of 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile (Formula I) according to the present disclosure Step (a) – Synthesis of a mixture of compounds of formula III and formula IV: A 500 mL four-necked round-bottom flask (RBF) was equipped with a condenser, thermometer sleeve, dropping funnel, and stirrer. At 30°C, with stirring, 50 g of 1-hydroxy-4-(4-tolyl)-3-oxo-1H-imidazol-2-carboxaldehyde oxime (Formula II) and 300 mL of dichloromethane (DCM) were added to the RBF to obtain the first reaction mixture. At 30°C, with stirring, 75 g of phosphorus trichloride (PCl3) was added to this reaction mixture. After the addition of PCl3, the reaction mixture was stirred at 30°C for 10 hours to obtain the first product mixture.

[0071] Post-processing: 300 mL of water was added to the first product mixture to obtain a two-phase mixture. The organic and aqueous layers of the two-phase mixture were separated. The separated aqueous layer was extracted with DCM. The combined DCM layers were concentrated to obtain a mixture of compounds of formula III and formula IV (yield: 50 g, mixture purity: 73%).

[0072] Step (b) – Synthesis of compound IV: A 500 mL four-necked RBF was equipped with a condenser, thermometer sleeve, dropping funnel, and stirrer. At 30°C, with stirring, 50 g of a mixture of compounds of formula III and IV and 200 mL of dimethylformamide (DMF) were added to the RBF to obtain a second reaction mixture. The second reaction mixture was heated at 90°C with stirring, and then at 90°C with stirring, 25 g of sodium metabisulfite was added and stirring continued for 5 hours to obtain a second product mixture.

[0073] Post-processing: Add 25 mL of water to the second product mixture, then slowly add the resulting product mixture to 600 mL of water and stir for 2 hours to obtain a solid. Filter the solid and wash it with 100 mL of water, then purify it with an aqueous acetone solution to obtain 35 g of compound IV (92% purity).

[0074] Step (c) – Synthesis of compound I: A 500 mL three-necked RBF was equipped with a thermometer sleeve, a dropping funnel, and a stirrer. At 30°C, 35 g of compound IV and 100 mL of water were added to the RBF to obtain a mixture. At 30°C, with stirring, 75 g (part 1) of sodium hypochlorite was added to this mixture; after the addition was complete, the mixture was stirred at 30°C for 2 hours to obtain a third reaction mixture. At 30°C, with stirring, 75 g (part 2) of sodium hypochlorite was added to the third reaction mixture, and stirring was continued at 30°C for 5 hours to obtain a third product mixture.

[0075] Post-processing: 100 mL of water was added to the third product mixture, and the product was extracted with 200 mL of ethyl acetate. The water and ethyl acetate were combined to obtain a two-phase mixture. The ethyl acetate layer was then dried with sodium sulfate, and the ethyl acetate was evaporated under reduced pressure to give 32 g of compound I (purity 93%, yield 68.58%).

[0076] Comparative example: Comparative Example 1: Conventional methods for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile In the first step, 0.95 mol of 1-hydroxy-4-(4-tolyl)-3-oxo-1H-imidazolium-2-carboxaldehyde oxime and 750 mL of N,N-dimethylacetamide were mixed in a 5-liter flask and heated to 100 °C. Sodium metabisulfite (235 g, 1.2 mol) was added in portions to obtain a mixture. The mixture was maintained at 100 °C for 8 hours to obtain a reaction mixture. The reaction mixture was cooled to room temperature and 2000 mL of water was added to precipitate the product. The solid was filtered off and washed with water and toluene, and the washed solid was dried. 139 g of crude (4-tolyl)-1H-imidazolium-2-carboxynitrile with a purity of 94.6% was obtained.

[0077] In the second step, 110 g of the product obtained in the first step was mixed with 55 mL of N,N-dimethylacetamide and 55 mL of acetonitrile in a 500 mL flask. 86 g of N-chlorosuccinimide (NCS) was added, maintaining the temperature below 25°C. After the addition was complete, the mixture was stirred at 20°C for 1 hour. The reactants were neutralized with 10% sodium hydroxide and stirred for 1 hour to obtain a crude product. The crude product was filtered, washed with water, re-slurried in toluene, filtered, and then dried in a vacuum oven to obtain 104 g of 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile (yield 50.3%, purity 70%).

[0078] The schematic process for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxylon according to Comparative Example 2 is shown in Scheme III below: .

[0079] As observed in Example 1 and Comparative Example 1, the method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile according to this disclosure is a simple and economical method, requiring minimal reagent amounts (catalytic amount only), and providing a final product 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile with relatively higher yield and higher purity.

[0080] Furthermore, the first step of the method disclosed herein is carried out at a relatively low temperature (30°C), whereas in the comparative example, the first step is carried out at 100°C. Therefore, the reaction conditions of the method disclosed herein are milder compared to the comparative example.

[0081] Furthermore, in the comparative example, chlorination was carried out using N-chlorosuccinimide (NCS). NCS is expensive and forms succinimide byproducts during the reaction. Removing these byproducts is very troublesome, requiring cumbersome post-treatment. In contrast, the chlorinating agent (i.e., sodium hypochlorite) used in the method of this disclosure is cheaper and does not form any byproducts.

[0082] Therefore, compared with conventional methods for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile, the method disclosed herein is simple, economical and efficient.

[0083] Technological progress The present disclosure described above has several technical advantages, including but not limited to a method for preparing 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile, the method being: ● Use harmless, inexpensive and readily available raw materials / reagents; ● Requires a relatively short reaction time; ● It produces relatively few impurities; ● Commercially scalable; ● Simple, efficient, cost-effective, and environmentally friendly; and ● It provides 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile with relatively higher purity and higher yield.

[0084] The embodiments described herein, along with their various features and advantages, will be explained with reference to the non-limiting embodiments described below. Descriptions of well-known components and processing techniques have been omitted to avoid unnecessarily obscuring the embodiments described herein. The examples used herein are intended only to facilitate understanding of possible implementations and to further enable those skilled in the art to implement the embodiments described herein. Therefore, these examples should not be construed as limiting the scope of the embodiments described herein.

[0085] The foregoing description of specific embodiments fully reveals the general nature of the embodiments described herein, enabling others to easily modify and / or adjust these specific embodiments for various applications without departing from the general concepts by applying present knowledge; therefore, such modifications and adjustments should and are intended to be understood as being within the meaning and scope of equivalents of the disclosed embodiments. It should be understood that the wording or terminology used herein is for descriptive purposes and not for limitation. Therefore, although the embodiments described herein have been described in conjunction with preferred embodiments, those skilled in the art will recognize that the embodiments described herein can be implemented with modifications within the spirit and scope of the embodiments described herein.

[0086] The use of the terms "at least" or "at least one" means that one or more elements or components or quantities may be used, as such use can achieve one or more intended objectives or results in the embodiments of the invention. While certain embodiments of the invention have been described, these embodiments are presented by way of example only and are not intended to limit the scope of the invention. Those skilled in the art, upon reviewing this disclosure, may make variations or modifications to the concept of the invention within the scope of the invention. Such variations or modifications are entirely within the spirit and scope of the invention.

[0087] Any discussion of documents, actions, materials, devices, articles, etc., included in this specification is for the purpose of providing background to this disclosure only. This should not be construed as an admission that any or all of these matters constitute part of the prior art, or as an admission that they were common general knowledge in the relevant field of this disclosure simply because they existed anywhere prior to the priority date of this application.

[0088] The values ​​given for various physical parameters, dimensions, and quantities are only approximate, and it can be expected that values ​​greater than the specified physical parameters, dimensions, and quantities fall within the scope of this invention, unless otherwise stated in the specification.

[0089] While this document has emphasized the specific features of the preferred embodiments, it should be understood that many additional features can be added and various changes can be made to the preferred embodiments without departing from the principles of this disclosure. These and other changes to the preferred embodiments of this disclosure will be apparent to those skilled in the art based on the disclosure herein, and it should be clearly understood that the foregoing descriptive content should be interpreted as illustrative only and not limiting.

Claims

1. A method for preparing 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile (Formula I), the method comprising the following steps: a) In a first fluid medium, under stirring and at a first predetermined temperature, the compound of formula II is treated with phosphorus halide for a first predetermined time period to obtain a mixture of the compound of formula III and the compound of formula IV; b) In a second fluid medium, under stirring and at a second predetermined temperature, a mixture of the compounds of formula III and formula IV is reduced using a reducing agent for a second predetermined time period to obtain the compound of formula IV. and c) In a third fluid medium, under stirring, at a third predetermined temperature, the compound of formula IV is chlorinated with a chlorinating agent for a third predetermined time period to obtain 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile (formula I). 。 2. The method according to claim 1, wherein, The first fluid medium is selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, toluene, ethyl acetate, xylene, benzene, tetrahydrofuran, 1,4-dioxane and combinations thereof.

3. The method according to claim 1, wherein, The phosphorus halide is phosphorus trichloride.

4. The method according to claim 1, wherein, The molar ratio of the compound of formula II to the phosphorus halide is in the range of 1:1.5 to 1:

5.

5. The method according to claim 1, wherein, The first predetermined temperature is in the range of 20°C to 50°C.

6. The method according to claim 1, wherein, The first predetermined time period is within the range of 5 to 24 hours.

7. The method according to claim 1, wherein, The second fluid medium is selected from the group consisting of dimethylacetamide, dimethylformamide, sulfolane, dimethyl sulfoxide, N-methylpyrrolidone, acetonitrile, and combinations thereof.

8. The method according to claim 1, wherein, The reducing agent is selected from the group consisting of sodium metabisulfite, sodium bisulfite, sodium sulfite, potassium bisulfite, potassium metabisulfite, potassium sulfite, potassium dithionite, sodium dithionite, and combinations thereof.

9. The method according to claim 1, wherein, The second predetermined temperature is in the range of 60°C to 150°C.

10. The method according to claim 1, wherein, The second predetermined time period is in the range of 2 to 10 hours.

11. The method according to claim 1, wherein, The chlorinating agent is selected from the group consisting of sodium hypochlorite, phosphorus oxychloride, phosphorus pentachloride, sulfur chloride, and sulfur dichloride.

12. The method according to claim 1, wherein, The third fluid medium is water.

13. The method according to claim 1, wherein, The molar ratio of the compound of formula IV to the chlorinating agent is in the range of 1:1 to 1:

15.

14. The method according to claim 1, wherein, The third predetermined temperature is in the range of 20°C to 50°C.

15. The method according to claim 1, wherein, The third predetermined time period is in the range of 2 to 10 hours.

16. The method according to claim 1, wherein, The yield of the 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile is in the range of 65% to 80%.

17. 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxynitrile prepared by the method according to any one of claims 1 to 16.

18. The 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxylon according to claim 17, wherein the purity of the 4-chloro-5-(4-tolyl)-1H-imidazol-2-carboxylon is greater than 90%.

19. The 4-chloro-5-(4-tolyl)-1H-imidazolium-2-carboxynitrile according to claim 18, wherein, The purity is in the range of 90% to 99%.

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