阅读说明：本技术 一种2-丙腈磺酰基乙腈的合成方法 (Synthetic method of 2-propionitrile sulfonyl acetonitrile ) 是由 田丽霞 张民 刘鹏 彭鹏鹏 赵光华 张茜 于 2020-06-02 设计创作，主要内容包括：本发明属于电解液添加剂的合成技术领域,提出了一种2-丙腈磺酰基乙腈的合成方法,包括A、在氮气气氛下,将3-巯基丙酸甲酯、溴乙酸甲酯和四氢呋喃混合,搅拌,降温至-5℃-5℃后加入叔丁醇钠,室温反应1-1.5h,得到化合物Ⅰ；B、将化合物Ⅰ和乙腈混合,搅拌,在5-10℃,pH值调至7,在0-5℃滴加催化剂、氧化剂,保温30-40min,得化合物Ⅱ；C、将化合物Ⅱ与30％质量分数的氨水混合,搅拌3-4h,至0-5℃,过滤得化合物Ⅲ；D、将化合物Ⅲ与乙腈混合,升温至60-70℃,滴加三氯氧磷,于60-70℃反应3-3.5h,加入8％质量分数的碳酸氢钠水溶液,乙酸乙酯萃取,分液,浓缩得2-丙腈磺酰基乙腈。通过上述技术方案,解决了现有技术中2-丙腈磺酰基乙腈的合成方法副产物多,收率低的问题。(The invention belongs to the technical field of synthesis of electrolyte additives, and provides a synthesis method of 2-propionitrile sulfonyl acetonitrile, which comprises the following steps of A, mixing 3-mercaptopropionic acid methyl ester, bromoacetic acid methyl ester and tetrahydrofuran in a nitrogen atmosphere, stirring, cooling to-5 ℃, adding tert-butyl alcohol sodium, and reacting at room temperature for 1-1.5 hours to obtain a compound I; B. mixing the compound I and acetonitrile, stirring, adjusting pH to 7 at 5-10 deg.C, dripping catalyst and oxidant at 0-5 deg.C, and keeping the temperature for 30-40min to obtain compound II; C. mixing the compound II with 30% ammonia water by mass fraction, stirring for 3-4h to 0-5 ℃, and filtering to obtain a compound III; D. mixing the compound III with acetonitrile, heating to 60-70 ℃, dropwise adding phosphorus oxychloride, reacting at 60-70 ℃ for 3-3.5h, adding 8 mass percent of sodium bicarbonate aqueous solution, extracting with ethyl acetate, separating liquid, and concentrating to obtain the 2-propionitrile sulfonyl acetonitrile. By the technical scheme, the problems of more byproducts and low yield of the synthetic method of the 2-propionitrile sulfonyl acetonitrile in the prior art are solved.)

1. A synthetic method of 2-propionitrile sulfonyl acetonitrile is characterized by comprising the following steps:

A. under the nitrogen atmosphere, mixing 3-mercaptopropionic acid methyl ester, bromoacetic acid methyl ester and tetrahydrofuran, stirring, cooling to-5 ℃ to 5 ℃, adding sodium tert-butoxide, reacting at room temperature for 1-1.5h after 3-5min addition, then adding water for quenching, adjusting the pH value to 2, extracting, washing, and drying an organic phase to obtain a compound I;

B. mixing the compound I and acetonitrile, stirring, adjusting the pH value to 7 at 5-10 ℃, dropwise adding a mixture of a catalyst, potassium monopersulfate and sodium periodate at 0-5 ℃, keeping the temperature for 30-40min after dropwise adding for 2-3h, returning to room temperature, separating liquid, drying, performing suction filtration, and concentrating to obtain a compound II;

C. dissolving the compound II in an organic solvent, dropwise adding 30% ammonia water in mass fraction, stirring for 3-4h after 1h of dropwise adding, cooling to 0-5 ℃, and filtering to obtain a compound III;

D. mixing the compound III with acetonitrile, heating to 60-70 ℃, dropwise adding phosphorus oxychloride, reacting for 3-3.5h at 60-70 ℃ after 0.5-1h of dropwise adding, adding 8% of sodium bicarbonate aqueous solution by mass fraction, extracting with ethyl acetate, separating liquid, and concentrating in vacuum to obtain the 2-propionitrile sulfonyl acetonitrile.

2. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein the molar ratio of methyl 3-mercaptopropionate, methyl bromoacetate and sodium tert-butoxide in step a is 1: (1.05-1.2): (1-1.1).

3. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein the amount of tetrahydrofuran in step A is calculated by methyl 3-mercaptopropionate, and 5.5ml of tetrahydrofuran is added to 1g of methyl 3-mercaptopropionate.

4. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein in the step a, the pH is adjusted to 2 by using 9.5-10.5% by mass of hydrochloric acid; the water washing comprises the steps of combining the extracted organic phases and then washing with saturated salt water.

5. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein the amount of acetonitrile added in step B is 1g of compound I, and 3-4 mL of acetonitrile is added.

6. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein the molar ratio of compound i to sodium periodate and oxone in step B is 1: 3: (0.04-0.06); the mass ratio of the compound I to the catalyst is 1: (0.002-0.006); the catalyst comprises the following components in a mass ratio of 1: (1-1.3): (0.5-0.8) methyltrioctylammonium hydrogensulfate, tetrabutylammonium bromide, ruthenium trichloride.

7. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein in step B, the pH is adjusted to 7 with 10% by mass of sodium bicarbonate aqueous solution; the concentration conditions are-0.09 MPa and 60 ℃, and the concentration time is 20-30 min.

8. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein the mass ratio of the compound ii to ammonia water in the step C is 1: (0.8-1.5); the organic solvent in the step C is methanol; the amount of methanol added was calculated as compound II, and 1g of compound II was added to (3-4) mL of methanol.

9. The method for synthesizing 2-propionitrile sulfonyl acetonitrile of claim 1, wherein the molar ratio of compound iii to phosphorus oxychloride in step D is 1: (1.2-1.5); the mass ratio of the compound III to the sodium bicarbonate water solution is 1: (1-1.2); acetonitrile was added in an amount of 1g of Compound III to (3-4) mL of acetonitrile.

Technical Field

The invention belongs to the technical field of electrolyte additive synthesis, and relates to a synthesis method of 2-propionitrile sulfonyl acetonitrile.

Background

The electrolyte is used as an important component of the lithium ion battery and has a great influence on the high-temperature performance and the low-temperature performance of the lithium ion battery, and the 2-propionitrile sulfonyl acetonitrile is used as an electrolyte additive, so that the lithium ion battery has better cycle performance and storage performance at high temperature, and can have lower direct current impedance at low temperature, and the lithium ion battery has better high-temperature performance and low-temperature performance. However, the existing synthesis method of 2-propionitrile sulfonyl acetonitrile has the defects of complex reaction, more byproducts and low yield, and the high-temperature and low-temperature performance of the lithium ion battery can not be effectively improved when the method is applied to the lithium ion battery.

Disclosure of Invention

The invention provides a synthetic method of 2-propionitrile sulfonyl acetonitrile, which solves the problems of complex reaction, more byproducts and low yield of the synthetic method of the 2-propionitrile sulfonyl acetonitrile in the prior art.

The technical scheme of the invention is realized as follows:

a synthetic method of 2-propionitrile sulfonyl acetonitrile comprises the following steps:

A. under the nitrogen atmosphere, mixing 3-mercaptopropionic acid methyl ester, bromoacetic acid methyl ester and tetrahydrofuran, stirring, cooling to-5 ℃ to 5 ℃, adding sodium tert-butoxide, reacting at room temperature for 1-1.5h after 3-5min addition, then adding water for quenching, adjusting the pH value to 2, extracting, washing, and drying an organic phase to obtain a compound I;

B. mixing the compound I and acetonitrile, stirring, adjusting the pH value to 7 at 5-10 ℃, dropwise adding a mixture of a catalyst, potassium monopersulfate and sodium periodate at 0-5 ℃, keeping the temperature for 30-40min after dropwise adding for 2-3h, returning to room temperature, separating liquid, drying, performing suction filtration, and concentrating to obtain a compound II;

C. dissolving the compound II in an organic solvent, dropwise adding 30% ammonia water in mass fraction, stirring for 3-4h after 1h of dropwise adding, cooling to 0-5 ℃, and filtering to obtain a compound III;

D. mixing the compound III with acetonitrile, heating to 60-70 ℃, dropwise adding phosphorus oxychloride, reacting for 3-3.5h at 60-70 ℃ after 0.5-1h of dropwise adding, adding 8% of sodium bicarbonate aqueous solution by mass fraction, extracting with ethyl acetate, separating liquid, and concentrating in vacuum to obtain the 2-propionitrile sulfonyl acetonitrile.

Further, the molar ratio of the methyl 3-mercaptopropionate to the methyl bromoacetate to the sodium tert-butoxide in the step A is 1: (1.05-1.2): (1-1.1).

Further, the amount of tetrahydrofuran in said step A was calculated based on methyl 3-mercaptopropionate, and 5.5ml of tetrahydrofuran was added to 1g of methyl 3-mercaptopropionate.

Further, the pH value in the step A is adjusted to 2 by adopting 9.5 to 10.5 mass percent of hydrochloric acid; the water washing comprises the steps of combining the extracted organic phases and then washing with saturated salt water.

Further, the amount of acetonitrile added in said step B is based on the compound I, and 1g of the compound I is added to (3-4) mL of acetonitrile.

Further, the molar ratio of the compound I to the sodium periodate and the potassium monopersulfate in the step B is 1: 3: (0.04-0.06); the mass ratio of the compound I to the catalyst is 1: (0.002-0.006); the catalyst comprises the following components in a mass ratio of 1: (1-1.3): (0.5-0.8) methyltrioctylammonium hydrogensulfate, tetrabutylammonium bromide, ruthenium trichloride.

Further, in the step B, the pH value is adjusted to 7 by adopting 10% of sodium bicarbonate aqueous solution in mass fraction; the concentration conditions are-0.09 MPa and 60 ℃, and the concentration time is 20-30 min.

Further, the mass ratio of the compound II to the ammonia water in the step C is 1: (0.8-1.5); the organic solvent in the step C is methanol; the amount of methanol added was calculated as compound II, and 1g of compound II was added to (3-4) mL of methanol.

Further, the molar ratio of the compound III to the phosphorus oxychloride in the step D is 1: (1.2-1.5); the mass ratio of the compound III to the sodium bicarbonate water solution is 1: (1-1.2); acetonitrile was added in an amount of 1g of Compound III to (3-4) mL of acetonitrile.

The working principle and the beneficial effects of the invention are as follows:

1. the synthesis reaction process of the 2-propionitrile sulfonyl acetonitrile is simple, the reaction yield is high, and the specific synthetic route is as follows

Wherein, the compound I isCAS number: 7400-45-5; compound II, i.e.CAS number: 118993-35-4; compound v, i.e. 2-propionitrile sulfonylacetonitrile:CAS number: 1267163-64-3.

2. According to the invention, through the design of the catalyst and the oxidant in the process of synthesizing the compound II, the yield of the compound II is improved, and further the yield of the 2-propionitrile sulfonyl acetonitrile is improved.

The catalyst in the step B of the invention is singly ruthenium trichloride or singly trioctyl ammonium hydrogen sulfate and tetrabutylammonium bromide, and is applied to the catalytic oxidation reaction of potassium monopersulfate and sodium periodate, the yield of the obtained compound II is 150.13g and 148.016g, and the final yield of the 2-propionitrile sulfonyl acetonitrile is 49.17 percent and 48.25 percent, while the compound II yield is 183.20g and the final yield of the 2-propionitrile sulfonyl acetonitrile is 60.50 percent by adopting the compound catalyst of trioctyl ammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride, so that the reaction yield of the compound II synthesized in the step B is improved and the final yield of the 2-propionitrile sulfonyl acetonitrile is improved.

In the step B, potassium monopersulfate or sodium periodate is independently adopted as an oxidant, the yield of the obtained compound II is 156.47g and 141.67g, and the final yield of the 2-propionitrile sulfonyl acetonitrile is 51.01% and 46.18%.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a drawing showing the preparation of 2-propionitrile sulfonylacetonitrile according to example 1 of the present invention¹H NMR spectrum.

FIG. 2 is a drawing showing the preparation of 2-propionitrile sulfonylacetonitrile according to example 1 of the present invention¹³C NMR spectrum.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A synthetic method of 2-propionitrile sulfonyl acetonitrile comprises the following steps:

A. mixing 120.17g of methyl 3-mercaptopropionate, 168.278g of methyl bromoacetate and 661ml of tetrahydrofuran under a nitrogen atmosphere, stirring, cooling to 0 ℃, adding 105.71g of sodium tert-butoxide, reacting at room temperature for 1.2h after 4min, adding water for quenching, adjusting the pH value to 2 by using 10 mass percent hydrochloric acid, extracting, combining organic phases, washing with saturated salt water, and drying the organic phase to obtain 181.276g of a compound I;

B. mixing a compound I and 544ml acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 8 ℃, dropwise adding a mixture of 0.544g of catalyst, 8.971g of potassium monopersulfate and 605.10g of sodium periodate at 2 ℃, keeping the temperature for 35min after 2.5h of dropwise adding, returning to room temperature, separating, combining organic phases, drying, performing suction filtration, concentrating the filtrate at 60 ℃ for 30min under-0.09 MPa to obtain 183.20g of a compound II; the catalyst comprises the following components in a mass ratio of 1: 1.3: 0.5 parts of methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride;

C. dissolving the compound II in 550ml of methanol, dropwise adding 220g of 30% ammonia water, stirring for 3.5h after 1h of dropwise adding, cooling to 1 ℃, and filtering to obtain 135.57g of a compound III;

D. mixing the compound III with 407ml of acetonitrile, heating to 65 ℃, dropwise adding 149.83g of phosphorus oxychloride, completing dropwise addition after 0.6h, reacting the obtained mixture at 65 ℃ for 3.2h, adding 135.57g of 8% by mass of sodium bicarbonate aqueous solution, extracting with ethyl acetate, separating liquid, combining organic phases, recovering ethyl acetate under vacuum reduced pressure, concentrating at 45 ℃ for 30min, obtaining 95.73g of 2-propionitrile sulfonyl acetonitrile, wherein the total yield is 60.50%.

Example 2

A synthetic method of 2-propionitrile sulfonyl acetonitrile comprises the following steps:

A. mixing 120.17g of methyl 3-mercaptopropionate, 160.629g of methyl bromoacetate and 661ml of tetrahydrofuran under a nitrogen atmosphere, stirring, cooling to-5 ℃, adding 96.1g of sodium tert-butoxide, reacting at room temperature for 1h after 5min, adding water for quenching, adjusting the pH value to 2 by using 10.5 mass percent hydrochloric acid, extracting, combining organic phases, washing with saturated salt water, and drying the organic phase to obtain 183.390g of a compound I;

B. mixing a compound I with 733.56ml of acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 5 ℃, dropwise adding a mixture of 0.367g of catalyst, 10.89g of potassium monopersulfate and 612.16g of sodium periodate at 5 ℃, preserving the temperature for 40min after 2h of dropwise adding, returning to room temperature, separating liquid, combining organic phases, drying, performing suction filtration, concentrating the filtrate at 60 ℃ for 20min under the pressure of-0.09 MPa to obtain 183.65g of a compound II; the catalyst comprises the following components in a mass ratio of 1: 1: 0.8 parts of methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride;

C. dissolving the compound II in 735ml of methanol, dropwise adding 276g of 30% ammonia water, stirring for 3h after 1h of dropwise adding, cooling to 5 ℃, and filtering to obtain 135.57g of compound III;

D. mixing the compound III with 543ml of acetonitrile, heating to 60 ℃, dropwise adding 164.22g of phosphorus oxychloride, after 1h of dropwise adding, reacting the obtained mixture at 60 ℃ for 3.5h, adding 162.684g of 8% by mass sodium bicarbonate aqueous solution, extracting with ethyl acetate, separating liquid, combining organic phases, recovering ethyl acetate under vacuum reduced pressure, and concentrating at 45 ℃ for 45min to obtain 96.01g of 2-propionitrile sulfonyl acetonitrile, wherein the total yield is 60.68%.

Example 3

A synthetic method of 2-propionitrile sulfonyl acetonitrile comprises the following steps:

A. mixing 120.17g of methyl 3-mercaptopropionate, 183.576g of methyl bromoacetate and 661ml of tetrahydrofuran under a nitrogen atmosphere, stirring, cooling to 5 ℃, adding 100.905g of sodium tert-butoxide, reacting at room temperature for 1.5h after 3min, adding water for quenching, adjusting the pH value to 2 by using 9.5 mass percent hydrochloric acid, extracting, combining organic phases, washing with saturated salt water, and drying the organic phase to obtain 182.237g of a compound I;

B. mixing the compound I with 584ml of acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 10 ℃, dropwise adding a mixture of 1.093g of catalyst, 7.21g of potassium monopersulfate and 518.28g of sodium periodate at 0 ℃, keeping the temperature for 30min after 3h of dropwise addition, separating the liquid, combining organic phases, drying, performing suction filtration, concentrating the filtrate at 60 ℃ under-0.09 MPa for 25min to obtain 177.817g of compound II; the catalyst comprises the following components in a mass ratio of 1: 1.2: 0.6 parts of methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride;

C. dissolving the compound II in 552ml of methanol, dropwise adding 143g of 30% ammonia water, stirring for 4h after 1h of dropwise adding, cooling to 0 ℃, and filtering to obtain 129.359g of a compound III;

D. mixing the compound III with 395ml of acetonitrile, heating to 70 ℃, dropwise adding 122.541g of phosphorus oxychloride, completing dropwise addition within 0.5h, reacting the obtained mixture at 70 ℃ for 3h, adding 129.359g of 8% by mass sodium bicarbonate aqueous solution, extracting with ethyl acetate, separating liquid, combining organic phases, recovering ethyl acetate under vacuum reduced pressure, concentrating at 45 ℃ for 35min, obtaining 90.71g of 2-propionitrile sulfonyl acetonitrile, wherein the total yield is 57.33%.

Comparative example 1

Compared to example 1, the difference is only in step B: mixing a compound I and 544ml acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 8 ℃, dropwise adding a mixture of 0.544g of ruthenium trichloride, 8.971g of potassium monopersulfate and 605.10g of sodium periodate at 2 ℃, keeping the temperature for 35min after 2.5h of dropwise adding, returning to room temperature, separating, combining organic phases, drying, performing suction filtration, concentrating the filtrate at 60 ℃ for 30min under-0.09 MPa to obtain 150.13g of a compound II; the charge ratio in the other steps is the same, and 77.80g of 2-propionitrile sulfonyl acetonitrile is finally obtained, and the total yield is 49.17%.

Comparative example 2

Compared to example 1, the difference is only in step B: mixing a compound I and 544ml acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 8 ℃, dropwise adding a mixture of 0.544g of catalyst and 605.10g of sodium periodate at 2 ℃, preserving the temperature for 35min after 2.5h of dropwise adding, returning to room temperature, separating, combining organic phases, drying, performing suction filtration, and concentrating filtrate at-0.09 MPa and 60 ℃ to obtain 156.47g of a compound II; the catalyst comprises the following components in a mass ratio of 1: 1.3: 0.5 parts of methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride; the charge ratio in the other steps is the same, and 80.71g of 2-propionitrile sulfonyl acetonitrile is finally obtained, and the total yield is 51.01%.

Comparative example 3

Compared to example 1, the difference is only in step B: mixing a compound I and 544ml acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 8 ℃, dropwise adding a mixture of 0.544g of catalyst and 8.971g of potassium monopersulfate at 2 ℃, keeping the temperature for 35min after 2.5h of dropwise adding, returning to room temperature, separating, drying, combining organic phases, carrying out suction filtration, concentrating the filtrate at 60 ℃ under-0.09 MPa, and obtaining 141.67g of a compound II; the catalyst comprises the following components in a mass ratio of 1: 1.3: 0.5 parts of methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride; the charge ratio in the other steps is the same, and 73.07g of 2-propionitrile sulfonyl acetonitrile is finally obtained, and the total yield is 46.18%.

Comparative example 4

Compared to example 1, the difference is only in step B: mixing a compound I and 544ml acetonitrile, stirring, adjusting the pH value to 7 by adopting 10 mass percent of sodium bicarbonate aqueous solution at 8 ℃, dropwise adding a mixture of 0.544g of catalyst, 8.971g of potassium monopersulfate and 605.10g of sodium periodate at 2 ℃, keeping the temperature for 35min after 2.5h of dropwise adding, returning to room temperature, separating, combining organic phases, drying, performing suction filtration, concentrating the filtrate at 60 ℃ for 30min under-0.09 MPa to obtain 148.016g of a compound II; the catalyst comprises the following components in a mass ratio of 1: 1.3 methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide; the material feeding ratio in the other steps is the same, and 76.35g of 2-propionitrile sulfonyl acetonitrile is finally obtained, and the total yield is 48.25%.

As can be seen from example 1 and comparative examples 1 and 4, in the synthesis method of 2-propionitrile sulfonyl acetonitrile of the invention, ruthenium trichloride is adopted alone or methyltrioctylammonium hydrogen sulfate and tetrabutylammonium bromide are adopted alone as catalysts in step B, and the yield of the compound II obtained by applying the catalytic oxidation reaction of potassium monopersulfate and sodium periodate is 150.13g and 148.016g, the final yield of the 2-propionitrile sulfonyl acetonitrile is 49.17 percent and 48.25 percent, while the compound II yield is 183.20g and the final yield of the 2-propionitrile sulfonyl acetonitrile is 60.50 percent by adopting the catalyst compounded by methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride in the example 1, therefore, the catalyst is compounded by adopting methyltrioctylammonium hydrogen sulfate, tetrabutylammonium bromide and ruthenium trichloride, so that the reaction yield of the compound II synthesized in the step B is improved, and the final yield of the 2-propionitrile sulfonyl acetonitrile is further improved.

As can be seen from example 1 and comparative examples 2 and 3, in the synthesis method of 2-propionitrile sulfonyl acetonitrile of the invention, potassium monopersulfate or sodium periodate is used as an oxidizing agent in step B, the yield of the obtained compound II is 156.47g and 141.67g, and the yield of the final 2-propionitrile sulfonyl acetonitrile is 51.01% and 46.18%, while in example 1, the yield of the compound II is 183.20g and the yield of the final 2-propionitrile sulfonyl acetonitrile is 60.50% by using an oxidizing agent prepared by compounding potassium monopersulfate and sodium periodate, so that the reaction yield of the compound II synthesized in step B is improved, and the yield of the final 2-propionitrile sulfonyl acetonitrile is improved.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention.