Thioether oxidation catalyst, preparation method thereof and preparation method of pyroxasulfone

Abstract

The invention provides a thioether oxidation catalyst, a preparation method thereof and a preparation method of pyroxasulfone. The preparation method comprises the following steps: S1, preparing a selenium source and a first solvent into a first solution; s2, adding a Lewis acid source into the first solution, and performing first mixing to obtain a second solution; s3, adding an organic alkali ligand source into the second solution, and performing second mixing to obtain a third solution; and S4, carrying out solvothermal reaction on the third solution at 100-150 DEG C to obtain the thioether oxidation catalyst. A selenium source, a Lewis acid source and an organic alkali ligand source are subjected to a combined reaction according to a specific sequence and conditions, and finally the inorganic-organic hybrid selenite catalyst with a special structure is formed under a solvothermal condition. The obtained catalyst is high in active atom utilization rate and strong in reactant molecule adsorbability, is beneficial to deep oxidation of reactants, accelerates oxidation of thioether into sulfone, and improves reaction selectivity and production efficiency.

Description

Technical Field

[0001] The present invention relates to the field of organic synthesis, and more particularly, to a sulfide oxidation catalyst, a preparation method thereof, and a preparation method of pyroxasulfone. Background Art

[0002] As a new generation of highly efficient and broad-spectrum herbicides, pyroxasulfone has received extensive attention and application in agricultural production in recent years due to its unique chemical structure and excellent biological activity. Its mechanism of action mainly interferes with the biosynthesis of very long-chain fatty acids (VLCFAs) in plants, inhibits early seedling growth, and thus effectively controls weed infestation in crop fields. The synthesis of pyroxasulfone intermediates, especially the oxidation of sulfide intermediates, is a key technology in its production process, and this step directly determines the quality and yield of the final product. At present, the main technical routes for the oxidation of sulfide in pyroxasulfone involve various catalyst systems. Common catalysts include tungsten metal catalysts, noble metal complexes, inorganic acids, and ionic liquids, etc. They each have certain advantages, but some technical bottlenecks have also emerged in practical applications.

[0003] CN111393427A uses sodium tungstate as a catalyst and hydrogen peroxide as an oxidant, which can directly oxidize sulfide into sulfone products with a content greater than 99%. The disadvantage is that the reaction time is relatively long, requiring 8 - 10 hours, and the catalyst is difficult to separate and recycle, which is not conducive to industrial production. The catalyst used in CN 115850254 A is a palladium catalyst or a copper catalyst. The catalyst used has a high cost and a complex synthesis process, and at the same time, the product yield is not high. CN 114716429 A uses a functionalized acidic ionic liquid catalyst to improve the oxidation ability of hydrogen peroxide. The best reported result has a purity of 95.5% and a yield of 99.2%. However, using its ionic liquid as a catalyst has the disadvantages of high preparation cost, complex process, difficult recycling, and inability to produce continuously in batches, etc.

[0004] That is to say, the main catalysts for oxidizing existing sulfide intermediates to obtain pyroxasulfone are tungsten metal catalysts, noble metal complexes, inorganic acids, ionic liquids, etc., but there are the following problems: 1. Batch process, high process risk. Limited by the heat transfer and mass transfer of batch equipment itself, the general reaction time is long, resulting in poor selectivity of the product sulfone; 2. The catalyst system is relatively concentrated, mainly tungsten-based catalysts or noble metals, and the cost price of the catalyst is relatively expensive.

[0005] Based on this, there is an urgent need to develop a new catalyst system for the oxidation of sulfide-containing pyroxasulfone intermediates, which can not only significantly reduce production costs, simplify the production process, but also be applicable to continuous production processes, while maintaining the high efficiency and selectivity of the reaction, reducing the impact on the environment, and providing a more optimized and sustainable solution for the industrial production of pyroxasulfone. Summary of the Invention

[0006] The main object of the present invention is to provide a thioether oxidation catalyst, a preparation method thereof, and a preparation method of pyroxasulfone, so as to solve the problem that the catalysts in the prior art cannot catalyze the oxidation of the thioether-containing pyroxasulfone intermediate with high conversion rate and high selectivity, and prepare pyroxasulfone in high yield.

[0007] To achieve the above object, a first aspect of the present invention provides a preparation method of a thioether oxidation catalyst, including: Step S1, preparing a first solution by mixing a selenium source and a first solvent; Step S2, adding a Lewis acid source to the first solution, and obtaining a second solution after the first mixing; Step S3, adding an organic base ligand source to the second solution, and obtaining a third solution after the second mixing; Step S4, carrying out a solvothermal reaction on the third solution at 100°C to 150°C to obtain the thioether oxidation catalyst.

[0008] Further, the first solvent includes water and acetonitrile, and the molar ratio of the selenium source to water is 1:(20 - 90). In the first solvent, the volume ratio of water to acetonitrile is (2 - 3):1; and / or, Step S1 is carried out at 30°C to 40°C.

[0009] Further, in Step S2, the molar ratio of the selenium source to the Lewis acid source is 1:(0.1 - 3.0); and / or, the time of the first mixing is 0.5 h to 1.0 h, and the first mixing is carried out at 25 ± 2°C.

[0010] Further, in Step S3, the molar ratio of the selenium source to the organic base ligand source is 1:(0.8 - 2.0); and / or, the time of the second mixing is 0.5 h to 1.0 h, and the second mixing is carried out at 30°C to 40°C.

[0011] Further, in Step S4, the reaction temperature of the solvothermal reaction is 110°C to 130°C, and the reaction time is 8 h to 15 h.

[0012] Further, the selenium source is selected from one or more of elemental selenium, selenium oxide, selenite, and selenate; the selenite is selected from one or more of sodium selenite, potassium selenite, zinc selenite, and barium selenite, and the selenate is selected from one or more of sodium selenate, zinc selenate, copper selenate, and potassium selenate; the Lewis acid source is selected from one or more of a metal source and an ammonium source, and the metal source is selected from one or more of a zinc source, a vanadium source, an iron source, a molybdenum source, an aluminum source, a titanium source, and a copper source; the metal source is added in the form of one or several of nitrate, basic sulfate, chloride, potassium salt, and ammonium salt, and the ammonium source is added in the form of chloride; the organic base ligand source is selected from one or more of ethylenediamine, triethylamine, 1,8-diazabicyclo[5,4,0]-undec-7-ene, 1,5-diazabicyclo[4,3,0]-5-nonene, 1,4-diazabicyclo[2,2,2]octane, N-methylpyrrolidine, and tert-butylamine; preferably, the Lewis acid source is selected from one or more of zinc nitrate, zinc chloride, ammonium metavanadate, iron nitrate, ammonium heptamolybdate, aluminum nitrate, titanium oxysulfate, potassium metatitanate, copper chloride, and ammonium chloride.

[0013] The second aspect of the present invention provides a thioether oxidation catalyst, which is prepared by the preparation method of the above-mentioned thioether oxidation catalyst.

[0014] The third aspect of the present invention provides a preparation method of pyroxasulfone. The sulfone intermediate of pyroxasulfone containing thioether undergoes an oxidation reaction with hydrogen peroxide under the action of a thioether oxidation catalyst to obtain pyroxasulfone; the sulfone intermediate of pyroxasulfone containing thioether has the structure shown in the following formula I:

[0015]

[0016] Formula I.

[0017] Further, before the oxidation reaction, the preparation method of pyroxasulfone further includes a step of activating the thioether oxidation catalyst. The activation treatment includes: in an organic solvent, mixing hydrogen peroxide and the thioether oxidation catalyst, and performing a stirring treatment for 1 h to 2 h to activate the thioether oxidation catalyst; wherein, the molar ratio of hydrogen peroxide to the thioether oxidation catalyst is (0.5 to 1.0):1.

[0018] Further, in the oxidation reaction, the feeding rate of the thioether oxidation catalyst is 0.1 g / min to 0.2 g / min; the feeding rate of the sulfone intermediate of pyroxasulfone containing thioether is 1.2 g / min to 1.5 g / min; the addition form of hydrogen peroxide is dropwise addition, and the dropping rate is 1.0 g / min to 1.5 g / min; the residence time of hydrogen peroxide is 0.5 h to 2 h, and the reaction temperature of the oxidation reaction is 40°C to 65°C.

[0019] Applying the technical solution of the present invention, the selenium source, the Lewis acid source and the organic base ligand source are combined and reacted in a specific order and conditions, and finally an inorganic-organic hybrid selenite catalyst with a special structure is formed under solvothermal conditions. The obtained catalyst has a high active atom utilization rate and strong adsorption to reactant molecules, which is beneficial to the deep oxidation of reactants, accelerates the oxidation of thioether to sulfone, improves the reaction selectivity, and also improves the production efficiency. At the same time, the catalyst prepared by the present invention has the remarkable characteristics of fast reaction speed, mild reaction conditions and high product purity. In addition, the preparation process of the present invention is simple, the reagents or catalysts are inexpensive, the catalyst can be recycled, and the continuous production of the catalyst in the coil is realized, reducing the adverse effects of large reaction heat release and high process risk, and providing feasibility for industrial production. Detailed Embodiments

[0020] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the embodiments.

[0021] As described in the background art, the catalysts in the prior art have the problem that they cannot catalyze the oxidation of the thioether-containing sulfone pyriftalid intermediate with high conversion rate and high selectivity and prepare sulfone pyriftalid with high yield. To solve the above technical problems, the first aspect of the present invention provides a preparation method of a thioether oxidation catalyst, including: Step S1, preparing a first solution by mixing a selenium source and a first solvent; Step S2, adding a Lewis acid source to the first solution, and after the first mixing, obtaining a second solution; Step S3, adding an organic base ligand source to the second solution, and after the second mixing, obtaining a third solution; Step S4, carrying out a solvothermal reaction on the third solution at 100 °C to 150 °C to obtain a thioether oxidation catalyst.

[0022] The technical solution of the present invention combines and reacts the selenium source, the Lewis acid source and the organic base ligand source in a specific order and conditions, and finally forms a selenite catalyst with a special structure and inorganic-organic hybridization under solvothermal conditions. Using [Se IV O3] 2-The unique trigonal pyramid configuration of the group enables its covalent bond synthesis with organic bases to form inorganic-organic hybrid selenites. In the crystal structure of the resulting compound, MO (metal-oxygen bond, or ammonia molecule bond) polyhedra are connected to SeO3 trigonal pyramids to form an inorganic layer, and the layers are connected through coordination bonds with organic ligands to form a multi-dimensional structure. Specifically, during the reaction process, the selenium source is first dissolved to make it evenly dispersed, providing a suitable reaction medium for subsequent reactions. Subsequently, a Lewis acid source is added to the stirred solution, and the selenium compound and the metal ions provided by the Lewis acid are initially connected through coordination bonds to form polyhedra. Then, an organic base ligand is added, and further coordination bonds are formed between it, the selenium compound, and the metal ions provided by the Lewis acid. In this step, a precursor containing an inorganic layer begins to form, with the SeO3 trigonal pyramid of selenium connected to the polyhedron of the central ion of the Lewis acid, initially constructing the basic unit of the inorganic layer. Finally, the system is transferred to a hydrothermal autoclave for a solvothermal reaction to make the connection between the formed inorganic layer and the organic ligand stronger and promote the further improvement of the structure.

[0023] Meanwhile, the catalyst prepared by the present invention has the remarkable characteristics of fast reaction speed, mild reaction conditions, and high product purity. Moreover, the preparation process of the present invention is simple, the reagents or catalysts are inexpensive, the catalyst can be recycled and reused, and continuous production of the catalyst in a coil tube is achieved, reducing the adverse effects of large reaction heat release and high process risk, providing feasibility for industrial production.

[0024] Furthermore, it is preferred that the first solvent includes water and acetonitrile, and the molar ratio of the selenium source to water is 1:(20 - 90), more preferably 1:(20 - 50), thereby reducing the formation of unnecessary selenium clusters, so that the finally obtained catalyst has higher activity and better selectivity. And in the first solvent, the volume ratio of water to acetonitrile is preferably (2 - 3):1, in order to provide good solubility and more appropriate polarity, which helps the more uniform mixing of the selenium source with the Lewis acid and the organic base, thus forming a catalyst with a more stable structure. Also, it is preferred that step S1 is carried out at 30°C - 40°C, so as to achieve higher solubility and stability, providing a better reaction medium for the subsequent synthesis of the catalyst.

[0025] In several typical embodiments, the molar ratio of the selenium source to the Lewis acid source is 1:(0.1 - 3.0).

[0026] In step S2, it is more preferable that the molar ratio of the selenium source to the Lewis acid source is 1:(0.1 - 2.0), so as to promote the formation of a more stable hybrid structure between the Lewis acid source and the selenium source, while reducing the excessive passivation of the catalytic active sites, thereby enhancing the catalytic performance of the obtained catalyst. At the same time, in step S2, it is preferable that the time for the first mixing is 0.5 h - 1.0 h, and the first mixing is carried out at 25 ± 2 °C, so as to facilitate the more sufficient contact and reaction between the selenium source and the Lewis acid source, form a more uniformly distributed active center, and further improve the activity and stability of the catalyst in the thioether oxidation reaction.

[0027] In several typical embodiments, the molar ratio of the selenium source to the organic base ligand source is 1:(0.8 - 2.0).

[0028] In step S3, in order to promote the formation of more stable coordination bonds between the organic base among the inorganic layers, thereby more significantly optimizing the structure of the obtained catalyst and enhancing its catalytic performance, it is preferable that the molar ratio of the selenium source to the organic base ligand source is 1:(0.8 - 1.2); and / or, the time for the second mixing is 0.5 h - 1.0 h, and the second mixing is carried out at 30 °C - 40 °C.

[0029] In the above preparation process, finally, in step S4, a complete catalyst structure is formed through a solvothermal reaction. Preferably, the reaction temperature of the solvothermal reaction is 110 °C - 130 °C, and the reaction time is 8 h - 15 h. This temperature range and reaction time can more effectively promote the deep crystallization of the catalyst precursor and the coordination connection of the organic base ligand, forming a hybrid selenite catalyst with higher activity and selectivity and a three-dimensional structure.

[0030] In several typical embodiments, the selenium source is selected from one or more of elemental selenium, selenium oxide, selenite, and selenate; the selenite is selected from one or more of sodium selenite, potassium selenite, zinc selenite, and barium selenite, and the selenate is selected from one or more of sodium selenate, zinc selenate, copper selenate, and potassium selenate; the Lewis acid source is selected from one or more of a metal source and an ammonium source, and the metal source is selected from one or more of a zinc source, a vanadium source, an iron source, a molybdenum source, an aluminum source, a titanium source, and a copper source; the metal source is added in the form of one or several of nitrate, basic sulfate, chloride, potassium salt, and ammonium salt, and the ammonium source is added in the form of chloride; the organic base ligand source is selected from one or more of ethylenediamine, triethylamine, 1,8-diazabicyclo[5,4,0]-undec-7-ene, 1,5-diazabicyclo[4,3,0]-5-nonene, 1,4-diazabicyclo[2,2,2]octane, N-methylpyrrolidine, and tert-butylamine. Among them, in particular, the zinc source, vanadium source, iron source, molybdenum source, titanium source, and copper source in the metal source can utilize their hollow or partially filled d orbitals to receive the lone pair electrons of the ligand; the aluminum source can utilize the empty valence s and p orbitals to accept the lone pair electrons of the ligand; and the ammonium source coordinates by using the empty orbitals formed by the sp3 hybridization of the nitrogen atom, and finally forms an inorganic layer connected to the SeO3 trigonal pyramid in the form of an MO (metal-oxygen bond, or ammonia molecule bond) polyhedron, forming a thioether oxidation catalyst with a stable structure and excellent catalytic performance. Further preferably, the Lewis acid source is selected from one or more of zinc nitrate, zinc chloride, ammonium metavanadate, iron nitrate, ammonium heptamolybdate, aluminum nitrate, titanium oxysulfate, potassium metatitanate, copper chloride, and ammonium chloride. These salts have higher compatibility with the above reaction system provided by the present invention, so as to help form a more stable catalyst structure and improve its catalytic performance.

[0031] In several particularly typical embodiments, the Lewis acid source includes a vanadium source (specifically ammonium metavanadate) and a zinc source (specifically zinc chloride), and the molar ratio of the vanadium source to the zinc source is 1:(0.4 - 0.5); or, the Lewis acid source includes a vanadium source (specifically ammonium metavanadate) and a copper source (specifically copper chloride), and the molar ratio of the vanadium source to the copper source is 1:(0.4 - 0.5). In these two types of schemes, the two Lewis acid sources can cooperate with the selenium source to form a more stable three-dimensional network structure, so that the obtained catalyst shows more stable catalytic activity and high product selectivity during the catalytic process.

[0032] The second aspect of the present invention provides a thioether oxidation catalyst, which is prepared by the preparation method of the above-mentioned thioether oxidation catalyst. Through each step in the above preparation method, the finally formed compound not only has high catalytic performance, but also shows multi-dimensional complexity in structure. The active atom utilization rate of the obtained catalyst is high, and the adsorption of reactant molecules is strong, which is beneficial to the deep oxidation of reactants, accelerates the oxidation of thioether to sulfone, improves the selectivity of the reaction, and also improves the production efficiency.

[0033] It should be particularly noted that due to the particularity of the material field and the limitations of existing testing and characterization means, it is difficult to comprehensively and quantitatively characterize the complex crystal structure and microstructure of the above-mentioned obtained catalyst. However, the performance test results show that the catalyst obtained in this application has better catalytic oxidation performance, and is particularly suitable for the oxidation reaction of the sulfentrazone intermediate containing thioether and hydrogen peroxide under the action of a thioether oxidation catalyst to obtain sulfentrazone.

[0034] The third aspect of the present invention provides a preparation method of sulfentrazone. The sulfentrazone intermediate containing thioether undergoes an oxidation reaction with hydrogen peroxide under the action of a thioether oxidation catalyst to obtain sulfentrazone; the sulfentrazone intermediate containing thioether has the structure shown in the following formula I:

[0035]

[0036] Formula I.

[0037] In the above preparation method of sulfentrazone, the mechanism of thioether oxidation is as follows: First, hydrogen peroxide first forms a hydrogen bond between the oxygen atom and the sulfur atom of the thioether, making the thioether become active. The activated thioether undergoes an oxidation reaction with hydrogen peroxide, in which the sulfur atom of the thioether undergoes an electrophilic attack on the oxygen atom to form an S-O single bond, thus generating a thiol intermediate. This intermediate continues to form a hydrogen bond with hydrogen peroxide, and the activated thiol undergoes an oxidation reaction with hydrogen peroxide, in which the sulfur atom of the thiol undergoes an electrophilic attack on the oxygen atom to form an S=O double bond (i.e., sulfoxide), and the sulfoxide is further oxidized once to become sulfone.

[0038] Based on this, in the above catalyst provided by the present invention, the selenite structure is coordinated by three oxygen atoms and is a trigonal pyramid (pseudo-tetrahedron) structure similar to an ammonia molecule. And there is a pair of active lone electron pairs on Se IV . In addition to the ortho-acid root, under different reaction conditions, acid roots such as HSeO3 - and Se2O5 2- may be formed. Due to Se IVA pair of active lone electron pairs on it can be regarded as an invisible structure-directing agent. This enables their stereochemistry to potentially form a non-centrosymmetric structure, thereby endowing the compound with some meaningful physical and chemical properties. Specifically, the covalently bonded compound (C2N2H8) prepared in Example 1 of the present invention 0.5 Zn3SeO3: This compound crystallizes in the P21 / n space group. Both zinc ions are six-coordinated, forming octahedral structures with oxygen and nitrogen atoms. Two ZnO5N octahedra and one ZnO6 octahedron form a Zn3O 12 N2 trimer through sharing edges. These trimers form chains by sharing vertex oxygen atoms and are then connected into a two-dimensional layered structure through SeO3 tetrahedra. This novel structure improves the atomic utilization rate of the catalyst during ligand reaction, is conducive to the adsorption and deep oxidation of reactants, accelerates the oxidation of thioether to sulfone, and improves the reaction selectivity and production efficiency.

[0039] Particularly, the obtained structure is especially suitable for the oxidation reaction of the sulfonepyrad intermediate containing thioether with hydrogen peroxide under the action of a thioether oxidation catalyst to obtain sulfonepyrad. Because this structure can more precisely adsorb the thioether intermediate of sulfonepyrad, promote the oxidation reaction between it and hydrogen peroxide, make the reaction path more direct, reduce the generation of by-products, and improve the purity of sulfonepyrad.

[0040] In several typical embodiments, before the oxidation reaction, the application further includes a step of activating the thioether oxidation catalyst. The activation treatment includes: mixing hydrogen peroxide and the thioether oxidation catalyst in an organic solvent and performing a stirring treatment for 1 h to 2 h to activate the thioether oxidation catalyst; wherein, the molar ratio of hydrogen peroxide to the thioether oxidation catalyst is (0.5 - 1.0):1.

[0041] The activation treatment activates the surface active centers of the catalyst through the pre-contact of hydrogen peroxide and the catalyst, enabling the catalyst to start the reaction more quickly in the subsequent oxidation reaction and enhancing its catalytic activity. Especially the activation time of 1 h to 2 h. Within this time range, the active centers of the catalyst are more fully activated, and the active centers will not be passivated or the structure will not be changed due to too long activation time, obtaining a better catalytic state. And the molar ratio range of (0.5 - 1.0):1 can more effectively promote the combination of hydrogen peroxide as an oxidant and the catalyst, thereby more precisely controlling the activation degree, enabling the catalyst to respond more quickly and catalyze the oxidation of thioether intermediates more efficiently to generate sulfonepyrad in the subsequent oxidation reaction.

[0042] In the above activation process, it is further preferred that the mass concentration of hydrogen peroxide is 25% - 50%. The interaction between hydrogen peroxide, the catalyst, and the reactants within this concentration range is milder, facilitating better maintenance of the structural stability of the catalyst while achieving activation.

[0043] In the oxidation reaction, the feeding rate of the thioether oxidation catalyst is 0.1 g / min - 0.2 g / min; the feeding rate of the sulfentrazone intermediate containing thioether is 1.2 g / min - 1.5 g / min; the addition form of hydrogen peroxide is dropwise addition, and the dropping rate is 1.0 g / min - 1.5 g / min. The preference for the above feeding rates promotes more uniform contact between the reactants and the catalyst during the reaction. Under these reaction conditions, the active sites of the catalyst can more effectively contact the thioether intermediate, accelerating the progress of the oxidation reaction, enabling the reaction to proceed smoothly and efficiently in continuous production, and improving production efficiency. By preferably setting the residence time of hydrogen peroxide to 0.5 h - 2.0 h and the reaction temperature of the oxidation reaction to 40°C - 65°C, the thermodynamic conditions of the reaction can be made more suitable, thus better balancing the reaction rate and product selectivity.

[0044] In addition, it is preferred that the sulfentrazone intermediate containing thioether is added in the form of an intermediate solution, and in the intermediate solution, the concentration of the sulfentrazone intermediate containing thioether is 0.5 ± 0.02 g / mL. At this concentration, the active components in the intermediate solution can more fully contact the active sites on the surface of the catalyst, further accelerating the progress of the oxidation reaction while maintaining the stability of the reaction system.

[0045] The following further describes the present application in detail with specific examples, which should not be construed as limiting the scope claimed by the present application.

[0046] Unless otherwise defined, all professional terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific examples and are not intended to limit the protection scope of the present invention.

[0047] Example 1

[0048] A preparation method of a thioether oxidation catalyst:

[0049] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 40°C until completely dissolved to obtain a first solution. Among them, selenium dioxide:water = 1:50, molar ratio.

[0050] (2) Add 37.9 g (0.278 mol) of zinc chloride (i.e., zinc source, selenium source: zinc source = 1:1, molar ratio) to the above first solution, and vigorously stir for 1 h at room temperature (25 ± 2 °C). Wait until it is completely dissolved and clear to obtain a second solution.

[0051] (3) Control the temperature to 30 to 40 °C, and gradually add 16.7 g (0.278 mol) of ethylenediamine (i.e., organic base ligand source, selenium dioxide: ethylenediamine = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by the temperature. After dropping, keep stirring for 0.5 h to obtain a third solution.

[0052] (4) Transfer the third solution system to a hydrothermal autoclave, heat it to 110 °C, and react for 8 h.

[0053] (5) After the reaction is completed, cool it to room temperature and filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid to an oven, dry it at 60 °C for 10 h to obtain a thioether oxidation catalyst.

[0054] Example 2

[0055] A preparation method of a thioether oxidation catalyst:

[0056] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water: acetonitrile = 2:1, volume ratio), and then weigh 96.08 g (0.556 mol) of sodium selenite and add it thereto, and stir at 35 °C until completely dissolved to obtain a first solution. Among them, sodium selenite: water = 1:25, molar ratio.

[0057] (2) Add 64.99 g (0.556 mol) of ammonium metavanadate and 37.86 g of zinc chloride (0.278 mol) (i.e., vanadium source, selenium source: vanadium source: zinc source = 1:1:0.5, molar ratio) to the above first solution, and vigorously stir for 1 h at room temperature (25 ± 2 °C). Wait until it is completely dissolved and clear to obtain a second solution.

[0058] (3) Control the temperature to 30 to 40 °C, and gradually add 56.22 g (0.555 mol) of triethylamine (i.e., organic base ligand source, sodium selenite: triethylamine = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by the temperature. After dropping, keep stirring for 0.5 h to obtain a third solution.

[0059] (4) Transfer the third solution system to a hydrothermal autoclave, heat it to 120 °C, and react for 15 h.

[0060] After the reaction is completed, cool down to room temperature and then filter. Then wash the product twice with purified water and acetonitrile respectively, with each usage amount being 200 mL. Transfer the washed solid to an oven, dry at 80 °C for 8 h to obtain the thioether oxidation catalyst.

[0061] Example 3

[0062] A preparation method of a thioether oxidation catalyst:

[0063] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), then weigh 87.47 g (0.463 mol) of sodium selenate and add it thereto, and stir at 35 °C until completely dissolved to obtain the first solution. Among them, sodium selenate:water = 1:30, molar ratio.

[0064] (2) Add 81.73 g (0.07 mol) of ammonium heptamolybdate (i.e., molybdenum source, selenium source:molybdenum source = 1:1.06, molar ratio) to the above first solution, stir vigorously at room temperature (25 ± 2 °C) for 0.5 h, and wait until it is completely clear to obtain the second solution.

[0065] (3) Control the temperature to 30 to 40 °C, and gradually add 46.85 g (0.463 mol) of triethylamine (i.e., organic base ligand source, sodium selenate:triethylamine = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by temperature. After dropping, keep stirring for 0.5 h to obtain the third solution.

[0066] (4) Transfer the third solution system to a hydrothermal kettle, heat to 125 °C, and react for 10 h.

[0067] (5) After the reaction is completed, cool down to room temperature and then filter. Then wash the product twice with purified water and acetonitrile respectively, with each usage amount being 200 mL. Transfer the washed solid to an oven, dry at 70 °C for 10 h to obtain the thioether oxidation catalyst.

[0068] Example 4

[0069] A preparation method of a thioether oxidation catalyst:

[0070] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), then weigh 80.06 g (0.463 mol) of sodium selenite and add it thereto, and stir at 35 °C until completely dissolved to obtain the first solution. Among them, sodium selenite:water = 1:30, molar ratio.

[0071] (2) Add 10.58 g (0.066 mol) of titanium oxysulfate (i.e., the titanium source, selenium source: titanium source = 1:0.143, molar ratio) to the above first solution, and stir vigorously at room temperature (25 ± 2 °C) for 0.5 h. Wait until it is completely dissolved and clear to obtain the second solution.

[0072] (3) Control the temperature to 30 to 40 °C, and gradually add 39.42 g (0.463 mol) of N-methylpyrrolidine (NMP) (i.e., the organic base ligand source, sodium selenite: NMP = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by the temperature. After dropping, keep stirring for 0.5 h to obtain the third solution.

[0073] (4) Transfer the third solution system to a hydrothermal autoclave, heat it to 110 °C, and react for 15 h.

[0074] (5) After the reaction is completed, cool it to room temperature and filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid to an oven, dry it at 80 °C for 10 h to obtain the thioether oxidation catalyst.

[0075] Example 5

[0076] A preparation method of a thioether oxidation catalyst:

[0077] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water: acetonitrile = 2:1, volume ratio), and then weigh 61.64 g (0.556 mol) of selenium dioxide and add it thereto, and stir at 35 °C until completely dissolved to obtain the first solution. Among them, selenium dioxide: water = 1:50, molar ratio.

[0078] (2) Add 37.35 g (0.278 mol) of copper chloride and 64.99 g of ammonium metavanadate (0.556 mol) (i.e., the copper source, selenium source: copper source: vanadium source = 1:0.5:1, molar ratio) to the above first solution, and stir vigorously at room temperature (25 ± 2 °C) for 1 h. Wait until it is completely dissolved and clear to obtain the second solution.

[0079] (3) Control the temperature to 30 to 40 °C, and gradually add 84.58 g (0.556 mol) of 1,8-diazabicyclo[5,4,0]-undec-7-ene (DBU) (i.e., the organic base ligand source, selenium dioxide: DBU = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by the temperature. After dropping, keep stirring for 1 h to obtain the third solution.

[0080] (4) Transfer the third solution system to a hydrothermal autoclave, heat it to 110 °C, and react for 12 h.

[0081] After the reaction is completed, cool down to room temperature and then filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid to an oven, dry at 65 °C for 12 h to obtain the thioether oxidation catalyst.

[0082] Example 6

[0083] A preparation method of a thioether oxidation catalyst:

[0084] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), then weigh 80.06 g (0.463 mol) of sodium selenite and add it thereto, and stir at 35 °C until completely dissolved to obtain the first solution. Among them, sodium selenite:water = 1:20, molar ratio.

[0085] (2) Add 81.74 g (0.07 mol) of ammonium heptamolybdate (i.e., molybdenum source, selenium source:molybdenum source = 1:0.15, molar ratio) to the above first solution, stir vigorously at room temperature (25 ± 2 °C) for 1 h, and wait until it is completely dissolved and clear to obtain the second solution.

[0086] (3) Control the temperature at 30 to 40 °C, and slowly add dropwise 51.93 g (0.463 mol) of 1,4-diazabicyclo[2,2,2]octane (DABCO) (i.e., organic base ligand source, sodium selenite:DABCO = 1:1, molar ratio) to the second solution. The dropping time is mainly controlled by temperature. After the dropping is completed, keep stirring for 1 h to obtain the third solution.

[0087] (4) Transfer the third solution system to a hydrothermal reactor, heat to 120 °C, and react for 12 h.

[0088] (5) After the reaction is completed, cool down to room temperature and then filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid to an oven, dry at 65 °C for 12 h to obtain the thioether oxidation catalyst.

[0089] Example 7

[0090] A preparation method of a thioether oxidation catalyst:

[0091] The difference between this example and Example 1 is only that: in step (1), change the dosage of water so that the volume ratio of water to acetonitrile is changed to 1:1; at the same time, change the temperature condition of stirring to 25 °C. Specifically:

[0092] (1) Weigh 100 g (5.56 mol) of deionized water and 100 mL of acetonitrile (i.e., water:acetonitrile = 1:1, by volume), then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 25 °C until completely dissolved to obtain a first solution. Among them, the molar ratio of selenium dioxide to water is 1:20.

[0093] Example 8

[0094] A preparation method of a thioether oxidation catalyst:

[0095] The difference between this example and Example 1 is only that: in step (1), the amount of water is changed so that the molar ratio of selenium dioxide to water is changed to 1:100, and the volume ratio of water to acetonitrile is changed to 4:1; at the same time, the temperature condition of stirring is changed to 45 °C. Specifically:

[0096] (1) Weigh 500 g (27.8 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 4:1, by volume), then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 45 °C until completely dissolved to obtain a first solution. Among them, the molar ratio of selenium dioxide to water is 1:100.

[0097] Example 9

[0098] A preparation method of a thioether oxidation catalyst:

[0099] The difference between this example and Example 1 is only that: in step (2), the amount of zinc source is changed so that the molar ratio of selenium source to zinc source is changed to 1:0.05; at the same time, the stirring time is changed to 0.4 h. Specifically:

[0100] (2) Add 1.89 g (0.0139 mol) of zinc chloride (i.e., zinc source, selenium source:zinc source = 1:0.05, molar ratio) to the above first solution, stir vigorously at room temperature (25 ± 2 °C) for 0.4 h, and wait until it is completely dissolved and clear to obtain a second solution.

[0101] Example 10

[0102] A preparation method of a thioether oxidation catalyst:

[0103] The difference between this example and Example 1 is only that: in step (2), the amount of zinc source is changed so that the molar ratio of selenium source to zinc source is changed to 1:3.5; at the same time, the stirring time is changed to 1.2 h. Specifically:

[0104] (2) Add 132.62 g (0.973 mol) of zinc chloride (i.e., the zinc source, selenium source: zinc source = 1:3.5, molar ratio) to the above first solution, and vigorously stir for 1.2 h at room temperature (25 ± 2 °C). Wait until it is completely dissolved and clear to obtain the second solution.

[0105] Example 11

[0106] A preparation method of a thioether oxidation catalyst:

[0107] The difference between this example and Example 1 is only that: in step (3), change the dosage of ethylenediamine so that the molar ratio of selenium dioxide to ethylenediamine changes to 1:0.5; at the same time, change the temperature condition of the stirring to 50 °C and the time to 0.4 h.

[0108] (3) Control the temperature at 50 °C, and gradually add 8.35 g (0.139 mol) of ethylenediamine (i.e., the organic base ligand source, selenium dioxide: ethylenediamine = 1:0.5, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by the temperature. After the dropping is completed, keep stirring for 0.4 h to obtain the third solution.

[0109] Example 12

[0110] A preparation method of a thioether oxidation catalyst:

[0111] The difference between this example and Example 1 is only that: in step (3), change the dosage of ethylenediamine so that the molar ratio of selenium dioxide to ethylenediamine changes to 1:2.5; at the same time, change the temperature condition of the stirring to 25 °C and the time to 1.2 h. Specifically:

[0112] (3) Control the temperature at 25 °C, and gradually add 41.8 g (0.695 mol) of ethylenediamine (i.e., the organic base ligand source, selenium dioxide: ethylenediamine = 1:2.5, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by the temperature. After the dropping is completed, keep stirring for 1.2 h to obtain the third solution.

[0113] Example 13

[0114] A preparation method of a thioether oxidation catalyst:

[0115] The difference between this example and Example 1 is only that: in step (4), change the temperature of the solvothermal reaction to 100 °C and the time to 18 h.

[0116] Example 14

[0117] A preparation method of a thioether oxidation catalyst:

[0118] The difference between this example and Example 1 is only that: in step (4), the temperature of the solvothermal reaction is changed to 150 °C and the time is changed to 6 h.

[0119] Comparative Example 1

[0120] A preparation method of a thioether oxidation catalyst:

[0121] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), and then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 40 °C until completely dissolved to obtain a first solution. Among them, selenium dioxide:water = 1:50, molar ratio.

[0122] (2) Control the temperature to 30 to 40 °C, and dropwise add 16.7 g (0.278 mol) of ethylenediamine (i.e., the organic base ligand source, selenium dioxide:ethylenediamine = 1:1, molar ratio) to the first solution. The dropping time is mainly controlled by temperature. After the dropping is completed, keep warm and stir for 0.5 h to obtain a second solution.

[0123] (3) Transfer the second solution system into a hydrothermal autoclave, heat to 110 °C, and react for 8 h.

[0124] (4) After the reaction is completed, cool to room temperature and filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid into an oven, and dry at a temperature of 60 °C for 10 h to obtain a thioether oxidation catalyst.

[0125] That is, the difference between this comparative example and Example 1 is only that: no Lewis acid source is added.

[0126] Comparative Example 2

[0127] A preparation method of a thioether oxidation catalyst:

[0128] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), and then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 40 °C until completely dissolved to obtain a first solution. Among them, selenium dioxide:water = 1:50, molar ratio.

[0129] (2) Add 37.9 g (0.278 mol) of zinc chloride (i.e., the zinc source, selenium source:zinc source = 1:1, molar ratio) to the above first solution, and stir vigorously at room temperature (25 ± 2 °C) for 1 h until it is completely dissolved and clear to obtain a second solution.

[0130] (3) Transfer the second solution system into a hydrothermal autoclave, heat to 110 °C, and react for 8 h.

[0131] After the reaction is completed, cool down to room temperature and then filter. Subsequently, wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid to an oven, dry at 60 °C for 10 h to obtain the thioether oxidation catalyst.

[0132] That is, the difference between this comparative example and Example 1 is only that: no organic base ligand source is added.

[0133] Comparative Example 3

[0134] A preparation method of a thioether oxidation catalyst:

[0135] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio), and then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 40 °C until completely dissolved to obtain the first solution. Among them, selenium dioxide:water = 1:50, molar ratio.

[0136] (2) Add 37.9 g (0.278 mol) of zinc chloride (i.e., zinc source, selenium source:zinc source = 1:1, molar ratio) to the above first solution, and stir vigorously at room temperature (25 ± 2 °C) for 1 h until it is completely clear to obtain the second solution.

[0137] (3) Control the temperature at 30 to 40 °C, and gradually add 16.7 g (0.278 mol) of acetic acid (i.e., organic base ligand source, selenium dioxide:acetic acid = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by temperature. After dropping, keep stirring for 0.5 h to obtain the third solution.

[0138] (4) Transfer the third solution system to a hydrothermal autoclave, heat to 110 °C, and react for 8 h.

[0139] After the reaction is completed, cool down to room temperature and then filter. Subsequently, wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid to an oven, dry at 60 °C for 10 h to obtain the thioether oxidation catalyst.

[0140] That is, the difference between this comparative example and Example 1 is only that: in step (3), an equimolar amount of acetic acid is used to replace ethylenediamine.

[0141] Comparative Example 4

[0142] A preparation method of a thioether oxidation catalyst:

[0143] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio). Then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 40 °C until completely dissolved to obtain a first solution. Among them, selenium dioxide:water = 1:50, molar ratio.

[0144] (2) Add 37.9 g (0.278 mol) of zinc chloride (i.e., zinc source, selenium source:zinc source = 1:1, molar ratio) to the above first solution, and vigorously stir at room temperature (25 ± 2 °C) for 1 h. Wait until it is completely clear after dissolution to obtain a second solution.

[0145] (3) Control the temperature to be 30 to 40 °C, and slowly add 16.7 g (0.278 mol) of ethylenediamine (i.e., organic base ligand source, selenium dioxide:ethylenediamine = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by temperature. After dropping, keep warm and stir for 0.5 h to obtain a third solution.

[0146] (4) Transfer the third solution system into a hydrothermal autoclave, heat to 80 °C, and react for 8 h.

[0147] (5) After the reaction is completed, cool down to room temperature and filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid into an oven, dry at 60 °C for 10 h to obtain a thioether oxidation catalyst.

[0148] Comparative Example 5

[0149] A preparation method of a thioether oxidation catalyst:

[0150] (1) Weigh 250 g (13.88 mol) of deionized water and 125 mL of acetonitrile (i.e., water:acetonitrile = 2:1, volume ratio). Then weigh 30.8 g (0.278 mol) of selenium dioxide and add it thereto, and stir at 40 °C until completely dissolved to obtain a first solution. Among them, selenium dioxide:water = 1:50, molar ratio.

[0151] (2) Add 37.9 g (0.278 mol) of zinc chloride (i.e., zinc source, selenium source:zinc source = 1:1, molar ratio) to the above first solution, and vigorously stir at room temperature (25 ± 2 °C) for 1 h. Wait until it is completely clear after dissolution to obtain a second solution.

[0152] (3) Control the temperature to be 30 to 40 °C, and slowly add 16.7 g (0.278 mol) of ethylenediamine (i.e., organic base ligand source, selenium dioxide:ethylenediamine = 1:1, molar ratio) dropwise to the second solution. The dropping time is mainly controlled by temperature. After dropping, keep warm and stir for 0.5 h to obtain a third solution.

[0153] (4) Transfer the third solution system into a hydrothermal reactor, heat it to 160 °C, and react for 8 h.

[0154] (5) After the reaction, cool down to room temperature and filter. Then wash the product twice with purified water and acetonitrile respectively, with a dosage of 200 mL each time. Transfer the washed solid into an oven, dry at 60 °C for 10 h to obtain the thioether oxidation catalyst.

[0155] Application Example 1

[0156] Use the thioether oxidation catalyst obtained in Example 1 as the catalyst used.

[0157] Before use, preliminarily activate the catalyst system used: Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 1 into a round-bottom flask, and then add 31.49 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to the thioether oxidation catalyst is 0.5:1, and the activation time is 1 h.

[0158] (1) Catalytic oxidation of thioether:

[0159] The feeding rate of the activated catalyst system is 0.1 g / min, the feeding rate of the acetonitrile solution of thioether (concentration: 0.52 g / ml) is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1 g / min, and they enter the coiled pipe. The reaction temperature is 65 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the residence time is controlled at 0.5 h. Use liquid phase to test the reaction results, as shown in Table 1.

[0160] (2) Catalytic oxidation of the sulfentrazone intermediate containing thioether to obtain sulfentrazone:

[0161] The feeding rate of the activated catalyst system is 0.1 g / min, the feeding rate of the acetonitrile solution of the sulfentrazone intermediate containing thioether (concentration: 0.52 g / ml) is 1.2 g / min, and the feeding rate of hydrogen peroxide is 1.5 g / min, and they enter the coiled pipe. The reaction temperature is 40 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the residence time is controlled at 2 h. Use liquid phase to test the reaction results. The conversion rate of the raw material after the reaction is 100%, and the selectivity of the product sulfentrazone is 97%.

[0162] The reaction route in this process is as follows.

[0163]

[0164] Application Example 2

[0165] Use the thioether oxidation catalyst obtained in Example 2 as the catalyst used.

[0166] Before use, conduct preliminary activation on the catalyst system used: Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 2 into a round-bottom flask, and then add 31.49 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to the thioether oxidation catalyst is 1:0.8, and the activation time is 1.5 h.

[0167] (1)Catalytic oxidation of thioether:

[0168] The feeding rate of the activated catalyst system is 0.2 g / min, the feeding rate of the acetonitrile solution of thioether (concentration: 0.52 g / ml) is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1 g / min. They enter the coil tube. The reaction temperature is 55 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the residence time is controlled at 1 h. Use liquid phase to test the reaction results, as shown in Table 1.

[0169] (2)Catalytic oxidation of the sulfentrazone intermediate containing thioether to obtain sulfentrazone:

[0170] The feeding rate of the activated catalyst system is 0.2 g / min, the feeding rate of the acetonitrile solution of the sulfentrazone intermediate containing thioether (concentration: 0.52 g / ml) is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1.5 g / min. They enter the coil tube. The reaction temperature is 65 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the residence time is controlled at 0.5 h. Use liquid phase to test the reaction results. The conversion rate of the raw material after the reaction is 100%, and the selectivity of the product sulfentrazone is 98%.

[0171] Application Example 3

[0172] Use the thioether oxidation catalyst obtained in Example 3 as the catalyst used.

[0173] Before use, conduct preliminary activation on the catalyst system used: Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 3 into a round-bottom flask, and then add 41.99 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to the thioether oxidation catalyst is 1:1, and the activation time is 2 h.

[0174] (1)Catalytic oxidation of thioether:

[0175] The feeding rate of the activated catalyst system is 0.2 g / min, the feeding rate of the acetonitrile solution of thioether (concentration: 0.52 g / ml) is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1 g / min. They enter the coil tube. The reaction temperature is 55 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the residence time is controlled at 1 h. Use liquid phase to test the reaction results, as shown in Table 1.

[0176] (2)Catalytic oxidation of the sulfonepyrasole intermediate containing thioether to obtain sulfonepyrasole:

[0177] The feeding rate of the activated catalyst system is 0.1 g / min, the feeding rate of the acetonitrile solution (concentration: 0.52 g / ml) of the sulfonepyrasole intermediate containing thioether is 1.2 g / min, and the feeding rate of hydrogen peroxide is 1 g / min. They enter the coiled pipe. The reaction temperature is 55 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the retention time is controlled at 1 h. The reaction result is tested by liquid phase. After the reaction, the conversion rate of the raw material is 100%, and the selectivity of the product sulfonepyrasole is 99%.

[0178] Application Example 4

[0179] Use the thioether oxidation catalyst obtained in Example 4 as the catalyst used.

[0180] Before use, conduct preliminary activation on the catalyst system used: Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 4 into a round-bottom flask, and then add 41.99 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to the thioether oxidation catalyst is 1:1.5, and the activation time is 1.5 h.

[0181] Catalytic oxidation of thioether:

[0182] The feeding rate of the activated catalyst system is 0.1 g / min, the feeding rate of the acetonitrile solution (concentration: 0.52 g / ml) of thioether is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1 g / min. They enter the coiled pipe. The reaction temperature is 50 °C. During this process, hydrogen peroxide is added dropwise in multiple portions, and the retention time is controlled at 1 h. The reaction result is tested by liquid phase. See Table 1.

[0183] Application Example 5

[0184] Use the thioether oxidation catalyst obtained in Example 5 as the catalyst used.

[0185] Before use, conduct preliminary activation on the catalyst system used: Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 5 into a round-bottom flask, and then add 56.68 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to the thioether oxidation catalyst is 1:2, and the activation time is 1.5 h.

[0186] Catalytic oxidation of thioether:

[0187] The feeding rate of the activated catalyst system is 0.1 g / min, the feeding rate of the acetonitrile solution of thioether (concentration: 0.52 g / ml) is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1 g / min. They enter the coiled pipe. The reaction temperature is 40°C. During this process, hydrogen peroxide is added drop by drop in multiple portions, and the retention time is controlled at 0.5 h. The reaction results are tested by liquid phase, as shown in Table 1.

[0188] Application Example 6

[0189] The thioether oxidation catalyst obtained in Example 6 is used as the catalyst.

[0190] Before use, the catalyst system used is preliminarily activated: Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 6 into a round-bottom flask, and then add 52.48 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to thioether oxidation catalyst is 1:2.5, and the activation time is 1 h.

[0191] Catalytic oxidation of thioether:

[0192] The feeding rate of the activated catalyst system is 0.15 g / min, the feeding rate of the acetonitrile solution of thioether (concentration: 0.52 g / ml) is 1.5 g / min, and the feeding rate of hydrogen peroxide is 1 g / min. They enter the coiled pipe. The reaction temperature is 40°C. During this process, hydrogen peroxide is added drop by drop in multiple portions, and the retention time is controlled at 1 h. The reaction results are tested by liquid phase, as shown in Table 1.

[0193] Application Example 7

[0194] The thioether oxidation catalyst obtained in Example 7 is used as the catalyst, activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether is achieved. The reaction results are tested by liquid phase, as shown in Table 1.

[0195] Application Example 8

[0196] The thioether oxidation catalyst obtained in Example 8 is used as the catalyst, activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether is achieved. The reaction results are tested by liquid phase, as shown in Table 1.

[0197] Application Example 9

[0198] The thioether oxidation catalyst obtained in Example 9 is used as the catalyst, activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether is achieved. The reaction results are tested by liquid phase, as shown in Table 1.

[0199] Application Example 10

[0200] Use the thioether oxidation catalyst obtained in Example 10 as the catalyst used, activate it according to the conditions in Application Example 1, and achieve the catalytic oxidation of thioether. The reaction results were tested by liquid phase, as shown in Table 1.

[0201] Application Example 11

[0202] Use the thioether oxidation catalyst obtained in Example 11 as the catalyst used, activate it according to the conditions in Application Example 1, and achieve the catalytic oxidation of thioether. The reaction results were tested by liquid phase, as shown in Table 1.

[0203] Application Example 12

[0204] Use the thioether oxidation catalyst obtained in Example 12 as the catalyst used, activate it according to the conditions in Application Example 1, and achieve the catalytic oxidation of thioether. The reaction results were tested by liquid phase, as shown in Table 1.

[0205] Application Example 13

[0206] Use the thioether oxidation catalyst obtained in Example 13 as the catalyst used, activate it according to the conditions in Application Example 1, and achieve the catalytic oxidation of thioether. The reaction results were tested by liquid phase, as shown in Table 1.

[0207] Application Example 14

[0208] Use the thioether oxidation catalyst obtained in Example 15 as the catalyst used, activate it according to the conditions in Application Example 1, and achieve the catalytic oxidation of thioether. The reaction results were tested by liquid phase, as shown in Table 1.

[0209] Application Example 15

[0210] In this application example, the system after the reaction in Application Example 5 was filtered to recycle the catalyst, and a recycled catalyst was obtained.

[0211] After that, use the obtained recycled catalyst as the catalyst used, and under the same reaction conditions as in Application Example 5, achieve the catalytic oxidation of thioether again. The reaction results were tested by liquid phase, as shown in Table 1.

[0212] Application Example 16

[0213] Use the thioether oxidation catalyst obtained in Example 1 as the catalyst used, and change the activation treatment to:

[0214] Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 1 to a round-bottom flask, and then add 31.49 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to thioether oxidation catalyst is 0.2:1, and the activation time is 2 h.

[0215] Subsequently, the catalytic oxidation of thioether was realized under the same conditions as in Application Example 1, and the reaction results were tested by liquid phase, as shown in Table 1.

[0216] Application Example 17

[0217] The thioether oxidation catalyst obtained in Example 1 was used as the catalyst, and the activation treatment was changed to:

[0218] Take 100 mL of acetonitrile, then add all the thioether oxidation catalyst obtained in Example 1 into a round-bottom flask, and then add 31.49 g of 30% hydrogen peroxide catalyst precursor. The molar ratio of hydrogen peroxide to thioether oxidation catalyst is 2:1, and the activation time is 0.2 h.

[0219] Subsequently, the catalytic oxidation of thioether was realized under the same conditions as in Application Example 1, and the reaction results were tested by liquid phase, as shown in Table 1.

[0220] Application Example 18

[0221] The thioether oxidation catalyst obtained in Example 1 was used as the catalyst for the catalytic oxidation of the sulfentrazone intermediate containing thioether, and it was activated according to the conditions in Application Example 1. The catalytic oxidation conditions of the sulfentrazone intermediate containing thioether were changed to:

[0222] The feeding rate of the catalyst system after activation was 0.5 g / min, the feeding rate of the acetonitrile solution (concentration 0.2 g / ml) of the sulfentrazone intermediate containing thioether was 0.5 g / min, and the feeding rate of hydrogen peroxide was 0.5 g / min, and they entered the coil pipe. The reaction temperature was 70 °C. During this process, hydrogen peroxide was added dropwise in multiple portions, and the retention time was controlled at 3 h. The reaction results were tested by liquid phase. The conversion rate of the raw material after the reaction was 91%, and the selectivity of the product sulfentrazone was 83%.

[0223] Application Comparative Example 1

[0224] The thioether oxidation catalyst obtained in Comparative Example 1 was used as the catalyst, and it was activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether was realized. The reaction results were tested by liquid phase, as shown in Table 1.

[0225] Application Comparative Example 2

[0226] The thioether oxidation catalyst obtained in Comparative Example 2 was used as the catalyst, and it was activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether was realized. The reaction results were tested by liquid phase, as shown in Table 1.

[0227] Application Comparative Example 3

[0228] The thioether oxidation catalyst obtained in Comparative Example 3 was used as the catalyst employed, activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether was achieved. The reaction results were tested by liquid phase, as shown in Table 1.

[0229] Application of Comparative Example 4

[0230] The thioether oxidation catalyst obtained in Comparative Example 4 was used as the catalyst employed, activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether was achieved. The reaction results were tested by liquid phase, as shown in Table 1.

[0231] Application of Comparative Example 5

[0232] The thioether oxidation catalyst obtained in Comparative Example 5 was used as the catalyst employed, activated according to the conditions in Application Example 1, and the catalytic oxidation of thioether was achieved. The reaction results were tested by liquid phase, as shown in Table 1.

[0233] Table 1

[0234]

[0235] From the above description, it can be seen that, compared with each comparative example, the above-mentioned embodiments of the present invention achieved the preparation of a structurally special, inorganic-organic hybrid selenite catalyst. The obtained catalyst accelerated the oxidation of thioether to sulfone, improved the selectivity of the reaction, and also improved the production efficiency, and was particularly suitable for the oxidation reaction of the sulfonepyrad intermediate containing thioether with hydrogen peroxide under the action of a thioether oxidation catalyst to obtain sulfonepyrad.

[0236] Specifically, comparing Examples 7 and 8 with Examples 1 to 6, it can be known that preferably the molar ratio of the selenium source to water, the volume ratio of water to acetonitrile, and the temperature condition where Step S1 is located can contribute to the more uniform mixing of the selenium source with the Lewis acid and the organic base, thereby forming a catalyst with a more stable structure.

[0237] Comparing Examples 9 and 10 with Examples 1 to 6, it can be known that preferably the molar ratio of the selenium source to the Lewis acid source can promote the formation of a more stable hybrid structure between the Lewis acid source and the selenium source, and at the same time reduce the excessive passivation of the active sites of the catalyst, thereby enhancing the catalytic performance of the obtained catalyst.

[0238] Comparing Examples 11 and 12 with Examples 1 to 6, it can be known that preferably the molar ratio of the selenium source to the organic base ligand source and the temperature condition where the second mixing is located can promote the formation of more stable coordination bonds of the organic base between the inorganic layers, thereby more significantly optimizing the structure of the obtained catalyst and enhancing its catalytic performance.

[0239] Comparing Examples 13 and 14 with Examples 1 to 6, it can be seen that by optimizing the temperature and time of the solvothermal reaction, the deep crystallization of the catalyst precursor and the coordination connection of the organic base ligand can be more effectively promoted, forming a hybrid selenite catalyst with a three-dimensional structure, higher activity and selectivity.

[0240] By comparing Examples 1 to 5, it can be known that when the Lewis acid source includes a vanadium source (specifically ammonium metavanadate) and a zinc source (specifically zinc chloride), and the molar ratio of the vanadium source to the zinc source is 1:(0.4 - 0.5); or when the Lewis acid source includes a vanadium source (specifically ammonium metavanadate) and a copper source (specifically copper chloride), and the molar ratio of the vanadium source to the copper source is 1:(0.4 - 0.5), the two Lewis acid sources can respectively cooperate with the selenium source to form a more stable three-dimensional network structure, so that the obtained catalyst shows more stable catalytic activity and high product selectivity during the catalytic process.

[0241] Moreover, from Application Example 15, it can be seen that the catalyst provided by the present invention can still exhibit excellent catalytic activity after being recycled.

[0242] In the catalytic oxidation of thioether, comparing Application Examples 16 and 17 with Application Example 1, it can be seen that by optimizing the molar ratio of hydrogen peroxide to the thioether oxidation catalyst and the activation time during the activation treatment of the thioether oxidation catalyst, the active center of the catalyst can be more fully activated, obtaining a better catalytic state, so as to more precisely control the activation degree, enabling the catalyst to respond more quickly and catalyze the oxidation of thioether intermediates more efficiently in the subsequent oxidation reaction.

[0243] In the catalytic oxidation of the sulfentrazone intermediate containing thioether, by optimizing the feeding rate of each raw material and the catalytic temperature and time conditions, the active sites of the catalyst can more effectively contact the thioether intermediate, accelerating the progress of the oxidation reaction, enabling the reaction to proceed smoothly and efficiently in continuous production, and ultimately better balancing the reaction rate and product selectivity. Also, it is simultaneously preferred that the sulfentrazone intermediate containing thioether is added in the form of an intermediate solution, and in the intermediate solution, the concentration of the sulfentrazone intermediate containing thioether is 0.5 ± 0.02 g / mL, thereby further accelerating the progress of the oxidation reaction while maintaining the stability of the reaction system.

[0244] It should be noted that the terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such terms can be interchanged under appropriate circumstances so that the embodiments of this application described here can be implemented in an order other than those described here, for example.

[0245] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of a thioether oxidation catalyst, characterized in that, Comprising: Step S1: Prepare a first solution by mixing a selenium source and a first solvent; Step S2: Add a Lewis acid source to the first solution, and after a first mixing, obtain a second solution; Step S3: Add an organic base ligand source to the second solution, and after a second mixing, obtain a third solution; Step S4: Carry out a solvothermal reaction on the third solution at 100°C to 150°C to obtain the thioether oxidation catalyst.

2. The preparation method of the thioether oxidation catalyst according to claim 1, characterized in that, In step S1, the first solvent includes water and acetonitrile, and the molar ratio of the selenium source to the water is 1:(20 - 90); in the first solvent, the volume ratio of the water to the acetonitrile is (2 - 3):1; and / or, step S1 is carried out at 30°C to 40°C.

3. The preparation method of the thioether oxidation catalyst according to claim 2, characterized in that, In step S2, the molar ratio of the selenium source to the Lewis acid source is 1:(0.1 - 3.0); and / or, the time of the first mixing is 0.5 h to 1.0 h, and the first mixing is carried out at 25 ± 2°C.

4. The preparation method of the thioether oxidation catalyst according to any one of claims 1 to 3, characterized in that, In step S3, the molar ratio of the selenium source to the organic base ligand source is 1:(0.8 - 2.0); and / or, the time of the second mixing is 0.5 h to 1.0 h, and the second mixing is carried out at 30°C to 40°C.

5. The preparation method of the thioether oxidation catalyst according to any one of claims 1 to 3, characterized in that, In step S4, the reaction temperature of the solvothermal reaction is 110°C to 130°C, and the reaction time is 8 h to 15 h.

6. The method for preparing a thioether oxidation catalyst according to any one of claims 1 to 3, characterized in that, the selenium source is selected from one or more of elemental selenium, selenium oxide, selenite and selenate; the selenite is selected from one or more of sodium selenite, potassium selenite, zinc selenite and barium selenite, and the selenate is selected from one or more of sodium selenate, zinc selenate, copper selenate and potassium selenate; the Lewis acid source is selected from one or more of a metal source and an ammonium source, the metal source is selected from one or more of a zinc source, a vanadium source, an iron source, a molybdenum source, an aluminum source, a titanium source and a copper source; the metal source is added in the form of one or several of nitrate, basic sulfate, chloride, potassium salt and ammonium salt, and the ammonium source is added in the form of chloride; the organic base ligand source is selected from one or more of ethylenediamine, triethylamine, 1,8 - diazabicyclo[5,4,0]-undec-7-ene, 1,5 - diazabicyclo[4,3,0]-5-nonene, 1,4 - diazabicyclo[2,2,2]octane, N - methylpyrrolidine and tert-butylamine.

7. A thioether oxidation catalyst, characterized in that, The thioether oxidation catalyst is prepared by the method for preparing a thioether oxidation catalyst according to any one of claims 1 to 6.

8. A preparation method of oxasulfuron, characterized in that, Carry out an oxidation reaction on the sulfentrazone intermediate containing thioether and hydrogen peroxide under the action of the thioether oxidation catalyst according to claim 7 to obtain the sulfentrazone; the sulfentrazone intermediate containing thioether has the structure shown in formula I as follows: Formula I.

9. The preparation method of oxasulfuron according to claim 8, characterized in that, Before the oxidation reaction, the preparation method of the sulfentrazone further includes a step of activating the thioether oxidation catalyst, and the activation treatment includes: In an organic solvent, hydrogen peroxide is mixed with the thioether oxidation catalyst and subjected to stirring treatment for 1 h to 2 h to activate the thioether oxidation catalyst; wherein, the molar ratio of the hydrogen peroxide to the thioether oxidation catalyst is 1:(0.8 - 2.5).

10. The preparation method of oxasulfuron according to claim 8 or 9, characterized in that, In the oxidation reaction, the feeding rate of the thioether oxidation catalyst is 0.1 g / min to 0.2 g / min; the feeding rate of the sulfentrazone intermediate containing thioether is 1.2 g / min to 1.5 g / min; the addition form of the hydrogen peroxide is dropwise addition, and the dropping rate is 1.0 g / min to 1.5 g / min; the residence time of the hydrogen peroxide is 0.5 h to 2.0 h, and the reaction temperature of the oxidation reaction is 40°C to 65°C.

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