Application of zirconium hydroxide as catalyst for selective catalytic oxidation of sulfide to prepare sulfoxide and sulfone

Abstract

The application belongs to the technical field of organic synthesis, and particularly relates to selective oxidation of thioether to prepare sulfoxide and sulfone by using zirconium hydroxide as a catalyst. The application uses thioether as raw material, zirconium hydroxide as catalyst, and hydrogen peroxide as oxidant. Sulfoxide can be catalytically oxidized and synthesized in a short reaction time, and sulfone can be obtained by prolonging the reaction time. The selectivity can be regulated only by the reaction time without any additives. The zirconium hydroxide catalyst can be directly purchased or prepared by using a simple precipitation method with zirconium salt as a precursor, and is low in price. Hydrogen peroxide is used as an oxidant, and is green, stable, low in cost, high in atomic efficiency (47% active oxygen), and has water as the only by-product. In addition, the reaction process is simple in operation, low in cost, and high in yield, and has great industrial application prospect.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, specifically relating to the application of zirconium hydroxide as a catalyst for the selective catalytic oxidation of sulfides to prepare sulfoxides and sulfones. Technical Background

[0002] Sulfoxides and sulfones are promising organic compounds that can be used as drugs for treating gastric ulcers and antipsychotics. Common examples include omeprazole, ipramazole, pantoprazole, leminoprazole, and mesoridazine. They can also be used as insecticides and herbicides, such as fipronil and ethiprole. Because sulfoxides and sulfones contain polar functional groups such as thionyl and thionyl groups, they can coordinate with metal ions to form complexes, especially with precious metals such as gold, silver, platinum, and palladium. They can be used as metal extractants and can also remove sulfur-containing compounds from fuels by generating sulfoxides and sulfones. Sulfoxides and sulfones are also important auxiliaries, ligands, and intermediates in organic synthesis.

[0003] The oxidation of sulfides is the most direct method for preparing sulfoxides and sulfones. Traditional oxidants include: 1. Metal oxides and their salts, such as KMnO4 and CrO3; 2. Halogens and their halogenated derivatives, such as Br2, I2, NaClO2, and NaIO4; 3. Nitric acid and its nitrates, such as concentrated HNO3 and NaNO2; 4. Peroxides, such as peracetic acid (CH3COOOH), urea peroxide (UHP), tert-butyl hydroperoxide (TBHP), and hydrogen peroxide (H2O2); 5. Oxygen systems. However, the use of strong acids (such as concentrated HNO3) and high oxidation states (such as KMnO4 and NaIO4) as oxidants can impose a significant burden on the environment. Furthermore, the triplet spin ground state of oxygen makes it inert and difficult to utilize directly, often resulting in low conversion rates and selectivity. In contrast, hydrogen peroxide is considered an ideal green oxidant due to its advantages of being clean, stable, low-cost, having high atomic efficiency (47% active oxygen), and having water as the only byproduct. However, under mild conditions, the direct reaction of hydrogen peroxide with sulfide is very low. Therefore, a catalyst is needed to accelerate the decomposition of hydrogen peroxide into active oxygen.

[0004] Heterogeneous catalysts, characterized by high activity, recyclability, ease of separation, corrosion resistance, and minimal waste in liquid-phase reactions, have been widely used in industrial production. After many years of development, numerous heterogeneous catalysts have been developed for the selective oxidation of sulfides to prepare sulfoxides or sulfones. Reported noble metal catalysts include: one synthesized using a ligand engineering strategy, which synthesized three advanced titanium clusters (Ag4Ti) with different silver doping contents.14 (Ag4Ti6, Ag4Ti2) α-Ag2WO4, prepared by co-precipitation, is used to selectively oxidize sulfides to sulfoxides and produce sulfones (see *Journal of Catalysis*, 2023, Vol. 417, 185–193). α-Ag2WO4, prepared by co-precipitation, is used for the selective oxidation of sulfides to sulfoxides and sulfones (see *Applied Catalysis A: General*, 2023, Vol. 652, 119038). However, the use of precious metals increases production costs or complicates catalyst preparation processes. Reported transition metal catalysts include Cu–Ni–Co ternary metal oxides for the selective oxidation of sulfides to sulfoxides, using hydrogen peroxide as the oxidant and acetonitrile as the solvent, but the reaction time requires 25 hours (see *Materials Science & Engineering C–Materials for Biological Applications*, 2019, Vol. 103, 109814 pp.). A molybdenum-doped α-MnO2 catalyst is used for the selective oxidation of sulfides, but the solvent used is not environmentally friendly (toluene) and has low activity (yield 73%) (see *ACS Catalysis*, 2017, Vol. 7, No. 10, 7340–7345). Reported zirconium-based catalysts include a zirconium-based metal-organic framework material using a binaphthol derivative as a ligand for the selective photocatalytic oxidation of sulfides to sulfoxides (see *ACS Applied Materials & Interfaces*, 2023, Vol. 15, No. 5, 6982–6989).

[0005] Although many catalysts have been developed for the synthesis of sulfoxides and sulfones, many problems still need to be solved, such as harsh reaction conditions, complex catalyst preparation processes, and high prices. In order to solve these problems and further adapt to industrial production, it is of great significance to develop a catalyst with simple composition, low price, good recyclability, and high yield for the synthesis of sulfoxides and sulfones. Summary of the Invention

[0006] This invention discovers that by using zirconium hydroxide as a catalyst and adjusting the reaction time, sulfides can be selectively oxidized to sulfoxides and sulfones. This invention provides a novel, green, and efficient method for preparing sulfoxides and sulfones, which is simple, low-cost, safe, and has a high yield. Specifically, it includes the following:

[0007] In a first aspect, the present invention provides an application of zirconium hydroxide as a catalyst for the selective catalytic oxidation of sulfides to prepare sulfoxides and sulfones. The zirconium hydroxide catalyst can be purchased directly or obtained from a zirconium salt precursor. A certain amount of metal salt is dissolved in deionized water, sodium hydroxide solution is added dropwise until the pH > 9, and the mixture is stirred for 12 hours. The resulting precipitate is then filtered, washed, dried, and calcined to obtain the desired catalyst.

[0008] Secondly, this invention provides an application of zirconium hydroxide as a catalyst for the selective catalytic oxidation of sulfides to prepare sulfoxides and sulfones. The method is as follows: using the sulfide shown in formula (I) as a raw material, methanol or other solvents as the reaction solvent, zirconium hydroxide as a catalyst, and hydrogen peroxide as the oxidant, catalytic oxidation is performed to synthesize the sulfoxide shown in formula (II) and the sulfone shown in formula (III), wherein the organic solvent includes one of methanol, ethanol, acetonitrile, ethyl acetate, and isopropanol;

[0009]

[0010]

[0011] R1-R6 are selected from any one of hydrogen, alkyl, halogen, nitro, alkoxy, carbonyl, aryl, allyl, hydroxyl, amino, and alkynyl, but are not limited to the above substituents.

[0012] Preferably, R1-R6 are selected from hydrogen, methyl, ethyl, methoxy, carbonyl, fluorine, chlorine, nitro, and phenyl, respectively.

[0013] Preferably, the sulfide includes: phenyl methyl sulfide, phenyl ethyl sulfide, 4-methoxyanisole, 4-methylthioacetophenone, 4-fluoroanisole, 4-chloroanisole, 4-nitroanisole, and diphenyl sulfide.

[0014] Preferably, the ratio of the catalyst to the sulfide is 1-100 g: 1 mol.

[0015] Preferably, the ratio of the catalyst to the sulfide is 10-50 g: 1 mol.

[0016] Preferably, the ratio of the catalyst to the sulfide is 10-30 g: 1 mol.

[0017] Preferably, the ratio of the catalyst to the sulfide is 20g:1mol.

[0018] Preferably, the ratio of the reaction solvent to thioether is 1-15 L: 1 mol.

[0019] Preferably, the ratio of the reaction solvent to thioether is 1-10 L: 1 mol.

[0020] Preferably, the ratio of the reaction solvent to thioether is 1-5 L: 1 mol.

[0021] Preferably, the ratio of the reaction solvent to thioether is 3L:1mol.

[0022] Preferably, the molar ratio of hydrogen peroxide to sulfide is 1-5:1.

[0023] Preferably, the molar ratio of hydrogen peroxide to sulfide is 2-4:1.

[0024] Preferably, the molar ratio of hydrogen peroxide to sulfide is 3:1.

[0025] Preferably, the reaction solvent is methanol.

[0026] Preferably, the method includes the following steps: adding sulfide, zirconium hydroxide catalyst, and hydrogen peroxide to a reactor containing a reaction solvent; reacting at 20-50°C for 0.5-3 hours; and separating sulfoxide and sulfone by filtration, distillation, and recrystallization.

[0027] Preferably, the reaction temperature is 20-50°C.

[0028] Preferably, the reaction temperature is 30°C.

[0029] Preferably, the reaction time is 0.5-3 hours.

[0030] Preferably, the reaction time is 0.5 h to generate sulfoxide and 1 h to generate sulfone.

[0031] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0032] (1) The present invention uses zirconium hydroxide as a catalyst, which has low commercial cost, high activity, good selectivity, and can be prepared by a simple precipitation method. Compared with traditional catalysts, it greatly simplifies the catalyst preparation process, significantly reduces the catalyst cost, and is environmentally friendly. Moreover, the reaction conditions are milder than those of the sulfide selective oxidation catalysts commonly used in the market. (2) The sulfide used in the present invention is a basic raw material commonly used in industry and has low cost.

[0033] (3) The present invention uses hydrogen peroxide, which is clean, stable, low cost, has high atomic efficiency (47% active oxygen) and water as the only byproduct, as an oxidant, and the reaction temperature is low and the reaction time is short.

[0034] (4) The method described in this invention can catalytically oxidize sulfides into the corresponding sulfoxides and sulfones with good selectivity and high yield of the target product. Attached Figure Description

[0035] Figure 1Mass spectrum of phenylmethyl sulfoxide synthesized by the method described in Example 1;

[0036] Figure 2 Mass spectrum of phenylmethyl sulfone synthesized by the method described in Example 1;

[0037] Figure 3 Mass spectrum of phenylmethyl sulfoxide synthesized by the method described in Example 2;

[0038] Figure 4 Mass spectrum of phenylmethyl sulfone synthesized by the method described in Example 2;

[0039] Figure 5 Mass spectrum of phenylmethyl sulfoxide synthesized by the method described in Example 3;

[0040] Figure 6 Mass spectrum of phenylmethyl sulfone synthesized by the method described in Example 3;

[0041] Figure 7 Mass spectrum of phenylmethyl sulfoxide synthesized by the method described in Example 4;

[0042] Figure 8 Mass spectrum of phenylmethyl sulfone synthesized by the method described in Example 4;

[0043] Figure 9 Mass spectrum of phenylmethyl sulfoxide synthesized by the method described in Example 5;

[0044] Figure 10 Mass spectrum of phenylmethyl sulfone synthesized by the method described in Example 5;

[0045] Figure 11 Mass spectrum of phenylmethyl sulfoxide synthesized by the method described in Example 6;

[0046] Figure 12 Mass spectrum of phenylmethyl sulfone synthesized by the method described in Example 6;

[0047] Figure 13 Mass spectrum of phenylethyl sulfoxide synthesized by the method described in Example 7;

[0048] Figure 14 Mass spectrum of 4-methoxyanisidine sulfoxide, the product synthesized by the method described in Example 7;

[0049] Figure 15 Mass spectrum of 4-methyl sulfoxide acetophenone synthesized by the method described in Example 7;

[0050] Figure 16 Mass spectrum of 4-fluoroanisidine sulfoxide synthesized by the method described in Example 7;

[0051] Figure 17Mass spectrum of 4-chloroanisidine sulfoxide synthesized by the method described in Example 7;

[0052] Figure 18 Mass spectrum of the product 4-nitroanisidine sulfoxide synthesized by the method described in Example 7;

[0053] Figure 19 Mass spectrum of diphenyl sulfoxide synthesized by the method described in Example 7;

[0054] Figure 20 Mass spectrum of phenylethyl sulfone synthesized by the method described in Example 7;

[0055] Figure 21 Mass spectrum of 4-methoxyanisole, the product synthesized by the method described in Example 7;

[0056] Figure 22 Mass spectrum of 4-methyl sulfone acetophenone synthesized by the method described in Example 7;

[0057] Figure 23 Mass spectrum of the product 4-fluoroanisole synthesized by the method described in Example 7;

[0058] Figure 24 Mass spectrum of the product 4-chloroanisole synthesized by the method described in Example 7;

[0059] Figure 25 Mass spectrum of the product 4-nitroanisole synthesized by the method described in Example 7;

[0060] Figure 26 Mass spectrum of diphenyl sulfone synthesized by the method described in Example 7; Detailed Implementation

[0061] The present invention will be further described in detail below with reference to specific embodiments. The scope of protection of the present invention is not limited thereto. Unless otherwise specified, all raw materials used in the following embodiments can be purchased commercially.

[0062] Example 1: Synthesis of phenylmethyl sulfoxide and phenylmethyl sulfone using different reaction solvents

[0063] 1. Synthesis of phenylmethyl sulfoxide

[0064] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0065] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of ethanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0066] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of acetonitrile, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0067] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of ethyl acetate, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0068] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of isopropanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 0.5h, and finally filter, distill, and recrystallize.

[0069] The product phenylmethyl sulfoxide was obtained.

[0070] The yields of aniline products obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 1 below:

[0071] Table 1. Process parameters and yield of the product phenylmethyl sulfoxide according to the preparation method described in Example 1.

[0072]

[0073]

[0074] The mass spectrum of the main product synthesized in the above reaction is shown below. Figure 1 The mass spectra of the main products of the above five reactions are the same, so only one mass spectrum is provided. The structural formula of the product is shown in Formula 1 below. The above results show that zirconium hydroxide catalyst can selectively oxidize phenyl methyl sulfide to phenyl methyl sulfoxide using methanol, ethanol, acetonitrile, ethyl acetate, and isopropanol as reaction solvents; and with methanol as the reaction solvent, the yield of phenyl methyl sulfoxide can reach up to 95%.

[0075]

[0076] 2. Synthesis of phenylmethyl sulfone

[0077] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0078] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of ethanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0079] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of acetonitrile, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0080] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of ethyl acetate, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0081] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of isopropanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 1h, and finally filter, distill, and recrystallize.

[0082] The product phenylmethyl sulfone was obtained.

[0083] The yields of aniline obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 2 below:

[0084] Table 2. Process parameters and yield of the product phenylmethyl sulfone as described in Example 1.

[0085]

[0086] The mass spectrum of the main product synthesized in the above reaction is shown below. Figure 2 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided). The structural formula of the product is shown in Formula 2 below. The above results indicate that zirconium hydroxide catalyst can selectively oxidize phenyl methyl sulfide to phenyl methyl sulfone using methanol, ethanol, acetonitrile, ethyl acetate, and isopropanol as reaction solvents; and with methanol as the reaction solvent, the yield of phenyl methyl sulfone can reach up to 97%.

[0087]

[0088] Example 2: Synthesis of phenylmethyl sulfoxide and phenylmethyl sulfone using different amounts of reaction solvent.

[0089] 1. Synthesis of phenylmethyl sulfoxide

[0090] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0091] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0092] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0093] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0094] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 6L of methanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 0.5h, and finally filter, distill, and recrystallize.

[0095] The product phenylmethyl sulfoxide was obtained.

[0096] The yields of phenylmethyl sulfoxide obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 3 below:

[0097] Table 3. Process parameters and yield of the product phenylmethyl sulfoxide according to the preparation method described in Example 2.

[0098]

[0099] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 3As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfoxide; when the ratio of methanol to phenylmethyl sulfide is 2-6 L:1 mol, the yield of phenylmethyl sulfoxide obtained from the reaction can reach over 90%, with a maximum of 95%.

[0100]

[0101] 2. Synthesis of phenylmethyl sulfone

[0102] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0103] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0104] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0105] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0106] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 6L of methanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 1h, and finally filter, distill, and recrystallize.

[0107] The product phenylmethyl sulfone was obtained.

[0108] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 4 below:

[0109] Table 4. Process parameters and yield of the product phenylmethyl sulfone as described in Example 2.

[0110]

[0111] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 4 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfoxide; when the ratio of methanol to phenylmethyl sulfide is 2-6 L:1 mol, the yield of phenylmethyl sulfoxide obtained can reach over 90%, with a maximum of 97%.

[0112]

[0113] Example 3: Synthesis of phenylmethyl sulfoxide and phenylmethyl sulfone with different amounts of hydrogen peroxide added.

[0114] 1. Synthesis of phenylmethyl sulfoxide

[0115] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 1mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0116] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 2mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0117] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0118] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 4mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0119] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, followed by 5mol of hydrogen peroxide. React at 30℃ for 0.5h, and finally filter, distill, and recrystallize.

[0120] The product phenylmethyl sulfoxide was obtained.

[0121] The yields of phenylmethyl sulfoxide obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 5 below:

[0122] Table 5. Process parameters and yield of the product phenylmethyl sulfoxide according to the preparation method described in Example 3.

[0123]

[0124] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 5 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfoxide; when the molar ratio of hydrogen peroxide to phenylmethyl sulfide is 1-4:1, the yield of phenylmethyl sulfoxide obtained is above 85%; and when the molar ratio of hydrogen peroxide to aniline is 3:1, the yield of phenylmethyl sulfoxide obtained is as high as 95%.

[0125]

[0126] 2. Synthesis of phenylmethyl sulfone

[0127] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 1mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0128] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 2mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0129] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0130] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 4mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0131] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 5mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0132] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 6 below:

[0133] Table 6. Process parameters and yield of the product phenylmethyl sulfone as described in Example 3.

[0134]

[0135] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 6 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfoxide; when the molar ratio of hydrogen peroxide to phenylmethyl sulfide is 1-5:1, the yield of phenylmethyl sulfoxide obtained is above 95%; and when the molar ratio of hydrogen peroxide to aniline is 3:1, the yield of phenylmethyl sulfoxide obtained is as high as 97%.

[0136]

[0137] Example 4: Synthesis of phenylmethyl sulfoxide and phenylmethyl sulfone at different reaction temperatures

[0138] 1. Synthesis of phenylmethyl sulfoxide

[0139] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at room temperature for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0140] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 25℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0141] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0142] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 40℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0143] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, followed by 3mol of hydrogen peroxide. React at 50℃ for 0.5h, and finally filter, distill, and recrystallize.

[0144] The product phenylmethyl sulfoxide was obtained.

[0145] The yields of phenylmethyl sulfoxide obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 7 below:

[0146] Table 7. Process parameters and yield of the product phenylmethyl sulfoxide as described in Example 4.

[0147]

[0148] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 7 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that, at reaction temperatures ranging from room temperature to 50°C, using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfone; simultaneously, at reaction temperatures ranging from room temperature to 50°C, the yield of phenylmethyl sulfone obtained from the reaction is all above 80%; and at a reaction temperature of 30°C, the yield of phenylmethyl sulfoxide obtained from the reaction can reach as high as 95%.

[0149]

[0150] 2. Synthesis of phenylmethyl sulfone

[0151] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at room temperature for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0152] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 25℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0153] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0154] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 40℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0155] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, followed by 3mol of hydrogen peroxide. React at 50℃ for 1h, and finally filter, distill, and recrystallize.

[0156] The product phenylmethyl sulfone was obtained.

[0157] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 8 below:

[0158] Table 8. Process parameters and yield of the product phenylmethyl sulfone as described in Example 4.

[0159]

[0160] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 8 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that, at reaction temperatures ranging from room temperature to 50°C, using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfone; simultaneously, at reaction temperatures ranging from room temperature to 50°C, the yield of phenylmethyl sulfone obtained from the reaction is all above 80%; and at a reaction temperature of 30°C, the yield of phenylmethyl sulfone obtained from the reaction can reach as high as 97%.

[0161]

[0162] Example 5: Synthesis of phenylmethyl sulfoxide and phenylmethyl sulfone at different reaction times

[0163] 1. Synthesis of phenylmethyl sulfoxide

[0164] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.25h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0165] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.33h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0166] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0167] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.58h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0168] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 0.67h, and finally filter, distill, and recrystallize.

[0169] The product phenylmethyl sulfoxide was obtained.

[0170] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 9 below:

[0171] Table 9. Process parameters and yield of the product phenylmethyl sulfoxide according to the preparation method described in Example 5.

[0172]

[0173] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 9 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that, with a reaction time of 0.25-0.67 h, using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfoxide; and with a reaction time of 0.5 h, the yield of phenylmethyl sulfoxide obtained can reach up to 95%.

[0174]

[0175] 2. Synthesis of phenylmethyl sulfone

[0176] (1) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.83h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0177] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0178] (3) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 2h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0179] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 2.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0180] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 3h, and finally filter, distill, and recrystallize.

[0181] The product phenylmethyl sulfone was obtained.

[0182] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 10 below:

[0183] Table 10. Process parameters and yield of the product phenylmethyl sulfone as described in Example 5.

[0184]

[0185] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 10 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 2 below. The above results indicate that, with a reaction time of 0.83-2.5 h, using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfone; simultaneously, the yield of phenylmethyl sulfone obtained from the reaction is above 80% when the reaction time is 0.83 h-2.5 h; and when the reaction time is 1 h, the yield of phenylmethyl sulfone obtained from the reaction can reach 97%.

[0186]

[0187]

[0188] Example 6: Synthesis of phenylmethyl sulfoxide and phenylmethyl sulfone with different catalyst addition amounts

[0189] 1. Synthesis of phenylmethyl sulfoxide

[0190] (1) Add 10g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0191] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0192] (3) Add 30g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0193] (4) Add 40g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 0.5h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfoxide.

[0194] (5) Add 50g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, followed by 3mol of hydrogen peroxide. React at 30℃ for 0.5h, and finally filter, distill, and recrystallize.

[0195] The product phenylmethyl sulfoxide was obtained.

[0196] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 11 below:

[0197] Table 11. Process parameters and yield of the product phenylmethyl sulfoxide according to the preparation method described in Example 6.

[0198]

[0199] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 11As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 1 below. The above results indicate that when the reaction time is 0.5 seconds, methanol is used as the reaction solvent, hydrogen peroxide as the oxidant, and the ratio of catalyst to phenylmethyl sulfide is 10-50 g:1 mol, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfoxide; simultaneously, when the ratio of catalyst to phenylmethyl sulfide is 10-50 g:1 mol, the yield of phenylmethyl sulfoxide obtained from the reaction is above 80%; and when the ratio of catalyst to phenylmethyl sulfide is 30 g:1 mol, the yield of phenylmethyl sulfoxide obtained from the reaction can reach up to 95%.

[0200]

[0201] 2. Synthesis of phenylmethyl sulfone

[0202] (1) Add 10g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 2L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0203] (2) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 3L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0204] (3) Add 30g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 4L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0205] (4) Add 40g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0206] (5) Add 50g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of phenyl methyl sulfide and 5L of methanol, then add 3mol of hydrogen peroxide, react at 30℃ for 1h, and finally filter, distill and recrystallize to obtain the product phenyl methyl sulfone.

[0207] The yields of phenylmethyl sulfone obtained by the preparation methods described in (1)-(5) above were calculated, and the results are shown in Table 12 below:

[0208] Table 12. Process parameters and yield of the product phenylmethyl sulfone as described in Example 6.

[0209]

[0210]

[0211] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 12 As shown (the mass spectra of the main products of the above 5 reactions are the same, so only one mass spectrum is provided), the structural formula is shown in Formula 2 below. The above results indicate that, with a reaction time of 1 h, using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and a catalyst-to-phenylmethyl sulfide ratio of 10-50 g:1 mol, phenylmethyl sulfide can be catalytically oxidized to phenylmethyl sulfone; simultaneously, when the catalyst-to-phenylmethyl sulfide ratio is 10-50 g:1 mol, the yield of phenylmethyl sulfone obtained from the reaction is above 80%; and when the catalyst-to-phenylmethyl sulfide ratio is 20 g:1 mol, the yield of phenylmethyl sulfone obtained from the reaction can reach 97%.

[0212]

[0213] Example 7: Synthesis of phenylmethyl sulfoxide derivatives and phenylmethyl sulfone derivatives using different phenylmethyl sulfone derivatives

[0214] 1. Synthesis of sulfoxide derivatives

[0215] (1) 20g of zirconium hydroxide catalyst was added to a 50L reactor, followed by 1mol of phenyl ethyl sulfide, then 3L of methanol and 3mol of hydrogen peroxide. The mixture was reacted at 30℃ for 0.5h. Finally, the product, phenyl ethyl sulfoxide, was obtained by filtration, distillation, and recrystallization. The mass spectrum of the product is shown below. Figure 13 As shown, the structural formula is shown in Equation 1 below.

[0216]

[0217] (2) 20g of zirconium hydroxide catalyst was added to a 50L reactor, followed by 1mol of 4-methoxyanisole, then 3L of methanol and 3mol of hydrogen peroxide. The reaction was carried out at 30℃ for 0.5h. Finally, the product 4-methoxyanisole sulfoxide was obtained by filtration, distillation, and recrystallization. The mass spectrum of the product is shown below. Figure 14 As shown, the structural formula is shown in Equation 2 below.

[0218]

[0219] (3) 20g of zirconium hydroxide catalyst was added to a 50L reactor, followed by 1mol of 4-methylthioacetophenone, then 3L of methanol and 3mol of hydrogen peroxide. The mixture was reacted at 30℃ for 0.5h. Finally, the product 4-methyl sulfoxide acetophenone was obtained by filtration, distillation, and recrystallization. The mass spectrum of the product is shown below. Figure 15 As shown, the structural formula is shown in Equation 3 below.

[0220]

[0221] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of 4-fluoroanisidine sulfide, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 0.5h. Finally, filter, distill, and recrystallize to obtain the product 4-fluoroanisidine sulfoxide. The mass spectrum of the product is shown below. Figure 16 As shown, the structural formula is shown in Equation 4 below.

[0222]

[0223] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of 4-chloroanisole, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 0.5h. Finally, filter, distill, and recrystallize to obtain the product 4-chloroanisole sulfoxide. The mass spectrum of the product is shown below. Figure 17 As shown, the structural formula is shown in Equation 5 below.

[0224]

[0225] (6) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of 4-nitroanisole, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 0.5h. Finally, filter, distill, and recrystallize to obtain the product 4-nitroanisole sulfoxide. The mass spectrum of the product is shown below. Figure 18 As shown, the structural formula is shown in Equation 6 below.

[0226]

[0227] (7) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of diphenyl sulfide, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 0.5h. Finally, filter, distill, and recrystallize to obtain the product diphenyl sulfoxide. The mass spectrum of the product is shown below. Figure 19 As shown, the structural formula is shown in Equation 7 below.

[0228]

[0229] The yields of the sulfoxide derivatives obtained by the preparation methods described in (1)-(7) above were calculated, and the results are shown in Table 13 below:

[0230] Table 13 Process parameters and product yield of the preparation method described in Example 7

[0231]

[0232] The mass spectra of the main products in reactions 1-7 above are as follows: Figure 13-19 As shown above, the results indicate that using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenyl ethyl sulfide can be catalytically synthesized into phenyl ethyl sulfoxide with a yield of 91%; 4-methoxyanisole can be catalytically synthesized into 4-methoxyanisole with a yield of 92%; 4-methylthioacetophenone can be catalytically synthesized into 4-methylsulfoxide acetophenone with a yield of 76%; 4-fluoroanisole can be catalytically synthesized into 4-fluoroanisole with a yield of 93%; 4-chloroanisole can be catalytically synthesized into 4-chloroanisole with a yield of 92%; 4-nitroanisole can be catalytically synthesized into 4-xnitroanisole with a yield of 62%; and diphenyl sulfide can be catalytically synthesized into diphenyl sulfoxide with a yield of 38%. Therefore, the method of the present invention can catalytically synthesize phenyl methyl sulfoxide from phenyl methyl sulfide, and the yield of the target product is relatively high.

[0233] 2. Synthesis of sulfone derivatives

[0234] (1) 20g of zirconium hydroxide catalyst was added to a 50L reactor, followed by 1mol of phenylethyl sulfide, then 3L of methanol and 3mol of hydrogen peroxide. The mixture was reacted at 30℃ for 1h. Finally, the product phenylethyl sulfone was obtained by filtration, distillation, and recrystallization. The mass spectrum of the product is shown below. Figure 20 As shown, the structural formula is shown in Equation 1 below.

[0235]

[0236] (2) 20g of zirconium hydroxide catalyst was added to a 50L reactor, followed by 1mol of 4-methoxyanisole, then 3L of methanol and 3mol of hydrogen peroxide. The mixture was reacted at 30℃ for 1h. Finally, the product 4-methoxyanisole was obtained by filtration, distillation, and recrystallization. The mass spectrum of the product is shown below. Figure 21 As shown, the structural formula is shown in Equation 2 below.

[0237]

[0238] (3) 20g of zirconium hydroxide catalyst was added to a 50L reactor, followed by 1mol of 4-methylthioacetophenone, then 3L of methanol and 3mol of hydrogen peroxide. The mixture was reacted at 30℃ for 1h. Finally, the product 4-methylsulfonylacetophenone was obtained by filtration, distillation, and recrystallization. The mass spectrum of the product is shown below. Figure 22 As shown, the structural formula is shown in Equation 3 below.

[0239]

[0240] (4) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of 4-fluoroanisole, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 1h. Finally, filter, distill, and recrystallize to obtain the product 4-fluoroanisole. The mass spectrum of the product is shown below. Figure 23 As shown, the structural formula is shown in Equation 4 below.

[0241]

[0242] (5) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of 4-chloroanisole, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 1h. Finally, filter, distill, and recrystallize to obtain the product 4-chloroanisole. The mass spectrum of the product is shown below. Figure 24 As shown, the structural formula is shown in Equation 5 below.

[0243]

[0244] (6) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of 4-nitroanisole, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 1h. Finally, filter, distill, and recrystallize to obtain the product 4-nitroanisole. The mass spectrum of the product is shown below. Figure 25 As shown, the structural formula is shown in Equation 6 below.

[0245]

[0246] (7) Add 20g of zirconium hydroxide catalyst to a 50L reactor, then add 1mol of diphenyl sulfide, followed by 3L of methanol and 3mol of hydrogen peroxide. React at 30℃ for 1h. Finally, filter, distill, and recrystallize to obtain the product diphenyl sulfone. The mass spectrum of the product is shown below. Figure 26 As shown, the structural formula is shown in Equation 7 below.

[0247]

[0248] The yields of the sulfone derivatives obtained by the preparation methods described in (1)-(7) above were calculated, and the results are shown in Table 14 below:

[0249] Table 14 Process parameters and product yield of the preparation method described in Example 6

[0250]

[0251] The mass spectra of the main products in reactions 1-7 above are as follows: Figure 20-26 As shown above, the results indicate that using methanol as the reaction solvent, hydrogen peroxide as the oxidant, and zirconium hydroxide as the catalyst, phenyl ethyl sulfide can be catalytically synthesized into phenyl ethyl sulfone with a yield of 89%; 4-methoxyanisole can be catalytically synthesized into 4-methoxyanisole with a yield of 90%; 4-methylthioacetophenone can be catalytically synthesized into 4-methylsulfonylacetophenone with a yield of 73%; 4-fluoroanisole can be catalytically synthesized into 4-fluoroanisole with a yield of 90%; 4-chloroanisole can be catalytically synthesized into 4-chloroanisole with a yield of 90%; 4-nitroanisole can be catalytically synthesized into 4-xnitroanisole with a yield of 60%; and diphenyl sulfide can be catalytically synthesized into diphenyl sulfone with a yield of 21%. Therefore, the method of the present invention can catalytically synthesize phenyl methyl sulfone from phenyl methyl sulfide, and the yield of the target product is relatively high.

[0252] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. Application of zirconium hydroxide as a catalyst for the selective oxidation of sulfides to prepare sulfoxides or sulfones.

2. The application as described in claim 1, characterized in that: Using the sulfide shown in formula (I) as a raw material, zirconium hydroxide as a catalyst, and hydrogen peroxide as an oxidant, sulfoxide shown in formula (II) or sulfone shown in formula (III) is synthesized by catalytic oxidation. The reaction solvent includes one of methanol, ethanol, acetonitrile, ethyl acetate, and isopropanol. Equation (I) Equation (II) Equation (I) Equation (III) R1-R6 are selected from any one of hydrogen, alkyl, halogen, nitro, alkoxy, carbonyl, aryl, allyl, hydroxyl, amino, and alkynyl groups, respectively.

3. The application as described in claim 1, characterized in that, The zirconium hydroxide catalyst can be purchased directly or prepared using a simple precipitation method with zirconium salt as a precursor.

4. The application as described in claim 2, characterized in that, The ratio of catalyst to thioether is 1-50 g : 1 mol; the molar ratio of hydrogen peroxide to thioether is 1-5 : 1; and the ratio of reaction solvent to thioether is 1-5 L : 1 mol.

5. The application as described in claim 2, characterized in that, The sulfides include: phenyl methyl sulfide, phenyl ethyl sulfide, 4-methoxyanisole, 4-methylthioacetophenone, 4-fluoroanisole, 4-chloroanisole, 4-nitroanisole, and diphenyl sulfide.

6. The application as described in any one of claims 2, 3, 4, and 5, characterized in that: Sulfide, zirconium hydroxide catalyst, and hydrogen peroxide are added to a reactor containing a reaction solvent and reacted at 20-50°C for 0.5-3 h. The mixture is then filtered, distilled, and recrystallized to obtain sulfoxide or sulfone.

7. The application as described in claim 6, characterized in that, The reaction solvent to thioether ratio is 3 L : 1 mol; the catalyst to thioether ratio is 20 g : 1 mol; the hydrogen peroxide to thioether molar ratio is 3:1; the reaction temperature is 30℃; sulfoxide is generated in 0.5 h reaction time, and sulfone is generated in reaction time greater than 1 h.

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