A method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine and applications thereof

Abstract

The application relates to the technical field of organic synthesis, and particularly discloses a synthesis method and application of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. The synthesis method of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine comprises the following steps: 2,4,6-trichloro-1,3,5-triazine is added into methanol, sodium bicarbonate is added, and stirring and mixing are carried out to obtain a mixed solution; methyl mercaptan is added into the mixed solution at -10-0 DEG C, and stirring reaction is carried out at 10-30 DEG C for 2-3 hours to obtain a reaction solution; ice water is added into the reaction solution, standing is carried out, solid is collected through filtration, and drying is carried out to obtain 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. The 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine disclosed by the application can be used for synthesizing sulfonylurea herbicides, and has the characteristics of easy degradation, low toxicity, high activity and low cost.

Description

Technical Field

[0001] This application relates to the field of organic synthesis technology, and more specifically, to a method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine and its application. Background Technology

[0002] Sulfonylurea herbicides are among the most common herbicides worldwide, characterized by high activity, environmentally friendly formulations, broad-spectrum weed control, strong selectivity, and ease of use. However, sulfonylurea herbicides are not easily volatilized or photodegraded, and after application to the soil, they tend to remain in the soil for extended periods, posing a long-term residual hazard to subsequent crops.

[0003] Methionylsulfuron is a sulfonylurea herbicide containing a methylthio group. By introducing an easily degradable methylthio group, it effectively shortens the residual period while maintaining the high efficiency and low toxicity characteristics of sulfonylurea compounds. Currently, the synthetic route for methionylsulfuron is as follows: 2-amino-4-chloro-6-methoxypyrimidine and sodium methanethiol are used to synthesize 2-amino-4-methoxy-6-methylthiopyrimidine, and then 2-amino-4-methoxy-6-methylthiopyrimidine is reacted with methyl 2-carboxylate benzenesulfonyl isocyanate to synthesize methionylsulfuron.

[0004] However, the raw material costs of 2-amino-4-chloro-6-methoxypyrimidine and sodium methanethiol are relatively high, increasing the production cost of methimazole. Therefore, there is an urgent need for a low-cost sulfonylurea herbicide containing a methylthionyl group. Summary of the Invention

[0005] In order to reduce the production cost of sulfonylurea herbicides containing methylthio groups, this application provides a method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine and its application.

[0006] In a first aspect, this application provides a method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, employing the following technical solution:

[0007] A method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine includes the following steps:

[0008] S1: First, add 2,4,6-trichloro-1,3,5-triazine to methanol, stir and mix, then add sodium bicarbonate, stir and mix to obtain a mixture; add methanethiol to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 2 to 3 hours to obtain a reaction solution;

[0009] S2: Add ice water to the reaction solution, let stand, filter and collect the solid, dry the solid to obtain 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0010] By employing the above technical solution, 2,4,6-trichloro-1,3,5-triazine, sodium bicarbonate, and methanol are first mixed, and then methanethiol is added and stirred at -10 to 0°C. During the reaction, a chlorine substituent in 2,4,6-trichloro-1,3,5-triazine first replaces the mercapto group in methanethiol, and another chlorine substituent in 2,4,6-trichloro-1,3,5-triazine then replaces the methoxy group in methanol, yielding a reaction solution containing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. Finally, by lowering the reaction temperature, 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine precipitates as a white solid in the reaction solution. Therefore, through simple steps of settling, filtering, and drying, 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine with a purity exceeding 93% can be obtained.

[0011] The carbamate and isocyanate methods are commonly used synthetic methods for sulfonylurea herbicides. In the synthesis of sulfonylurea herbicides containing methylthio groups, 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine is reacted to synthesize 2-amino-4-methoxy-6-methylthio-1,3,5-triazine, which is then reacted with an arylsulfonyl isocyanate to obtain sulfonylurea herbicides containing methylthio groups. These herbicides are easily degraded, have low toxicity, and high activity. Furthermore, the price of 2,4,6-trichloro-1,3,5-triazine is significantly lower than that of 2-amino-4-chloro-6-methoxypyrimidine, reducing the production cost of sulfonylurea herbicides containing methylthio groups and facilitating their industrial production.

[0012] Preferably, in S1, the molar ratio of 2,4,6-trichloro-1,3,5-triazine to methanethiol is 1:(1.0 to 1.3).

[0013] By adopting the above technical solution, 2,4,6-trichloro-1,3,5-triazine and methanethiol are fed into the reaction in an alkaline methanol environment according to the above molar ratio. The substitution reaction efficiency of 2,4,6-trichloro-1,3,5-triazine and methanethiol is relatively high, which is beneficial to improving the yield of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0014] Preferably, in S1, the molar ratio of 2,4,6-trichloro-1,3,5-triazine to methanethiol is 1:(1.0 to 1.05).

[0015] Preferably, in S1, the molar ratio of 2,4,6-trichloro-1,3,5-triazine and methanethiol is 1:1.05.

[0016] By adopting the above technical solution and further optimizing the molar ratio of 2,4,6-trichloro-1,3,5-triazine and methanethiol as described above, a higher yield of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine can be obtained with a lower feed amount, which is beneficial for the industrial production of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0017] Preferably, in S1, the feeding ratio of 2,4,6-trichloro-1,3,5-triazine to methanol is 5g:(40-60)mL.

[0018] By adopting the above technical solution, 2,4,6-trichloro-1,3,5-triazine and methanol are fed in the above feeding ratio. 2,4,6-trichloro-1,3,5-triazine has high solubility in methanol, which is conducive to the substitution reaction between 2,4,6-trichloro-1,3,5-triazine and methanol, thereby increasing the yield of the final 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0019] Preferably, in S1, the molar ratio of 2,4,6-trichloro-1,3,5-triazine to sodium bicarbonate is 1:(2-4).

[0020] By adopting the above technical solution and feeding sodium bicarbonate according to the above molar ratio, the substitution reaction of 2,4,6-trichloro-1,3,5-triazine with methanethiol and methanol can be promoted, thereby increasing the reaction rate.

[0021] Preferably, in step S2, ice water is first added to the reaction solution and allowed to stand for 15 to 30 minutes. Then, the reaction solution at -5 to 0°C is filtered to collect the solid. Finally, the solid is dried to obtain 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0022] By adopting the above technical solution, it is beneficial to increase the yield of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine because 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine has low solubility in aqueous solution at low temperatures. Therefore, adding ice to the funnel in step S2 cools the reaction solution, causing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine to precipitate as a white solid.

[0023] Secondly, this application provides an application of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, employing the following technical solution:

[0024] The use of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, specifically its use in the preparation of sulfonylurea herbicides.

[0025] By adopting the above technical solution, the sulfonylurea herbicide containing the methylthio group synthesized from 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine is easily degraded, has low toxicity, high activity, low production cost, and is easy to carry out industrial production.

[0026] In summary, this application has the following beneficial effects:

[0027] 1. The synthesis process in this application uses low-cost raw materials, simple reaction steps, and low-temperature reaction conditions. It only requires dissolving 2,4,6-trichloro-1,3,5-triazine and sodium bicarbonate in methanol, and then adding methanethiol under low-temperature conditions for stirring to obtain a reaction solution containing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. After filtering and drying the reaction solution, 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine with high purity and high yield can be obtained.

[0028] 2. In the synthesis process of this application, the molar ratio of 2,4,6-trichloro-1,3,5-triazine and methanethiol is 1:(1.0~1.05), and the synthesized 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine has high yield and purity, and low feed cost, which is conducive to the industrial production of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine;

[0029] 3. This application synthesizes 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine using 2,4,6-trichloro-1,3,5-triazine, methanol, and methanethiol as raw materials. This synthesized 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine can be used to synthesize sulfonylurea herbicides containing methylthio groups. The resulting herbicide is easily degraded, has low toxicity, high activity, low raw material cost, and is easy to carry out industrial production. Attached Figure Description

[0030] Figure 1 This is the GCMS image of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine;

[0031] Figure 2 This is the 1H NMR spectrum of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. Detailed Implementation

[0032] The present application will be further described in detail below with reference to the embodiments.

[0033] Unless otherwise stated below, all raw materials used in the embodiments of this application are commercially available.

[0034] Methanethiol, physicochemical parameters 10% in propanediol, CAS number 74-93-1.

[0035] Example

[0036] Example 1

[0037] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, the specific structural formula of which is as follows:

[0038]

[0039] The above-described synthetic process for 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine is described below, with the following reaction equation:

[0040]

[0041] The above-mentioned synthesis process of a pyridine-N-oxide includes the following steps:

[0042] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (4.69g, 55.83mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 2h to obtain a reaction solution;

[0043] In the embodiments of this application, the molar ratio of 2,4,6-trichloro-1,3,5-triazine and methanethiol is 1:1.1.

[0044] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 20 minutes. Add the reaction solution to a funnel containing ice to filter the reaction solution within a temperature range of -5 to 0℃. Collect the solid and dry it until the moisture content is less than 5% to obtain a white solid.

[0045] Reference Figure 1 and Figure 2 Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, weighing 4.63 g, with a yield of 81% and a purity of 91%.

[0046] Examples 2-4

[0047] The 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine differs from Example 1 in that the amount and molar ratio of 2,4,6-trichloro-1,3,5-triazine and methanethiol are different in the synthesis process S1 of pyridine-N-oxide.

[0048] The following table shows the feed amounts and molar amounts of 2,4,6-trichloro-1,3,5-triazine and methanethiol in the synthesis process S1 of pyridine-N-oxide, as well as the weight, yield, and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine obtained in S2:

[0049]

[0050]

[0051] Data analysis of the table above shows that the 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine synthesized in Examples 1-4 of this application has a yield of 75-90% and a purity of 85-95%. This indicates that in the synthesis process of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, the molar ratio of 2,4,6-trichloro-1,3,5-triazine to methanethiol is 1:(1.0-1.3), resulting in 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine with high yield and purity.

[0052] Further analysis of the table above shows that Examples 2 and 3 have higher purity and yield compared to Examples 1 and 4. This indicates that in the synthesis process of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, a molar ratio of 2,4,6-trichloro-1,3,5-triazine to methanethiol of 1:(1.0–1.05) yields 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine with high yield, high purity, and low cost. In particular, the highest yield and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine are obtained when the molar ratio of 2,4,6-trichloro-1,3,5-triazine to methanethiol is 1:1.05.

[0053] Examples 5-6

[0054] The 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine differs from Example 1 in that the amounts of 2,4,6-trichloro-1,3,5-triazine and methanol are different in the synthesis process S1 of pyridine-N-oxide.

[0055] The following table shows the following parameters in the synthesis process S1 of pyridine-N-oxides: the feed amounts of 2,4,6-trichloro-1,3,5-triazine and methanol, and the yield and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine obtained in S2:

[0056]

[0057] Data analysis of the table above shows that the 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine synthesized in Examples 1, 5, and 6 of this application has a yield as high as 79-83% and a purity as high as 91-93%. This indicates that in the synthesis process of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine of this application, the feed ratio of 2,4,6-trichloro-1,3,5-triazine to methanol is 5g:(40-60)mL, resulting in 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine with high yield and purity.

[0058] Example 7

[0059] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, differing from Example 1 in that the synthesis process of the pyridine-N-oxide includes the following steps:

[0060] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (6.83g, 81.33mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 2.5h to obtain a reaction solution;

[0061] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 15 minutes. Add the reaction solution to a funnel containing ice to filter the reaction solution within a temperature range of -5 to 0℃. Collect the solid and dry it until the moisture content is less than 5% to obtain a white solid.

[0062] Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. 1 [H NMR (400MHz, CDCl3) δ 4.08 (s, 3H), 2.59 (s, 3H)], weight 4.63 g, yield 82%, purity 92%.

[0063] Example 8

[0064] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, differing from Example 1 in that the synthesis process of the pyridine-N-oxide includes the following steps:

[0065] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (4.69g, 55.83mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 3h to obtain a reaction solution;

[0066] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 30 minutes. Add the reaction solution to a funnel containing ice to filter the reaction solution within a temperature range of -5 to 0℃. Dry the solid until the moisture content is less than 5% to obtain a white solid.

[0067] Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. 1 [H NMR (400MHz, CDCl3) δ 4.08 (s, 3H), 2.59 (s, 3H)], weight 4.61 g, yield 79%, purity 89%.

[0068] Example 9

[0069] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, differing from Example 1 in that the synthesis process of the pyridine-N-oxide includes the following steps:

[0070] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (9.11g, 108.44mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 2h to obtain a reaction solution;

[0071] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 20 minutes. Add the reaction solution to a funnel containing ice to filter the reaction solution within a temperature range of -5 to 0℃. Dry the solid until the moisture content is less than 5% to obtain a white solid.

[0072] Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. 1 [H NMR (400MHz, CDCl3) δ 4.08 (s, 3H), 2.59 (s, 3H)], weight 4.62 g, yield 80%, purity 90%.

[0073] Example 10

[0074] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, differing from Example 1 in that the synthesis process of the 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine includes the following steps:

[0075] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (4.69g, 84.01mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 2h to obtain a reaction solution;

[0076] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 20min. Add the reaction solution to a funnel for filtration, collect the solid, and dry the solid until the moisture content is less than 5% to obtain a white solid.

[0077] Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. 1 [H NMR (400MHz, CDCl3) δ 4.08 (s, 3H), 2.59 (s, 3H)], weight 4.59 g, yield 76%, purity 86%.

[0078] Analysis of the yield and purity of Examples 1 and 10 showed that, compared to Example 10, the yield of Example 1 increased by 6.58% and the purity increased by 5.81%. This indicates that in the synthesis process S2 of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, filtering the reaction solution at a low temperature promotes the precipitation of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine as a white solid, thereby improving the yield and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0079] Example 11

[0080] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, differing from Example 1 in that the synthesis process of the 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine includes the following steps:

[0081] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (4.69g, 55.83mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at 20-25℃, and stir and react at 10-30℃ for 2h to obtain a reaction solution;

[0082] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 20 minutes. Add the reaction solution to a funnel containing ice to filter the reaction solution within a temperature range of -5 to 0℃. Dry the solid until the moisture content is less than 5% to obtain a white solid.

[0083] Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. 1 [H NMR (400MHz, CDCl3) δ 4.08 (s, 3H), 2.59 (s, 3H)], weight 4.51 g, yield 72%, purity 83%.

[0084] Analysis of the yield and purity of Examples 1 and 11 showed that, compared to Example 11, the yield of Example 1 increased by 12.50%, and the purity increased by 9.64%. This indicates that in the synthesis process S1 of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, adding methanethiol to the reaction solution at -10 to 0°C can improve the yield and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. The reason for this may be that methanethiol has a low boiling point and is easily volatile, thus affecting the yield and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

[0085] Example 12

[0086] A 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, differing from Example 1 in that the synthesis process of the 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine includes the following steps:

[0087] S1: First, add 2,4,6-trichloro-1,3,5-triazine (5g, 27.11mmol) to methanol (50mL), stir and mix to dissolve, then add sodium bicarbonate (4.69g, 55.83mmol), stir and mix to obtain a mixture; add methanethiol (14.35g, 29.83mmol) to the mixture at -10 to 0℃, and stir and react at 35 to 45℃ for 2h to obtain a reaction solution;

[0088] S2: Add ice water (200mL) to the reaction solution. A white solid precipitates in the reaction solution. Then let the reaction solution stand for 20 minutes. Add the reaction solution to a funnel containing ice to filter the reaction solution within a temperature range of -5 to 0℃. Dry the solid until the moisture content is less than 5% to obtain a white solid.

[0089] Upon testing, the white solid was identified as 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. 1 [H NMR (400MHz, CDCl3) δ 4.08 (s, 3H), 2.59 (s, 3H)], weight 4.58 g, yield 74%, purity 84%.

[0090] Analysis of the yield and purity of Examples 1 and 12 shows that, compared to Example 12, the yield of Example 1 increased by 9.46% and the purity increased by 8.33%. This indicates that controlling the reaction temperature to -10 to 30°C in the synthesis process S1 of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine is beneficial for promoting the substitution reaction between 2,4,6-trichloro-1,3,5-triazine and methanethiol and methanol, thereby improving the yield and purity of 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine. This specific embodiment is merely an explanation of this application and is not intended to limit it. Those skilled in the art can make modifications to this embodiment without contributing any inventive step after reading this specification, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine, characterized in that, Includes the following steps: S1: First, add 2,4,6-trichloro-1,3,5-triazine to methanol, stir and mix, then add sodium bicarbonate, stir and mix to obtain a mixture; add methanethiol to the mixture at -10 to 0℃, and stir and react at 10 to 30℃ for 2 to 3 hours to obtain a reaction solution; S2: Add ice water to the reaction solution, let stand, filter and collect the solid, dry the solid to obtain 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine; In S1, the molar ratio of 2,4,6-trichloro-1,3,5-triazine to methanethiol is 1:(1.0 to 1.1); In S1, the feeding ratio of 2,4,6-trichloro-1,3,5-triazine to methanol is 5g:(40-60)mL; In S1, the molar ratio of 2,4,6-trichloro-1,3,5-triazine to sodium bicarbonate is 1:(2-4).

2. The method for synthesizing 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine according to claim 1, characterized in that, In step S2, ice water is first added to the reaction solution and allowed to stand for 15 to 30 minutes. Then, the reaction solution at -5 to 0°C is filtered to collect the solid. Finally, the solid is dried to obtain 2-chloro-4-methoxy-6-methylthio-1,3,5-triazine.

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