Catalyst for preparing deuterated dimethyl sulfoxide, application and preparation method of deuterated dimethyl sulfoxide

Abstract

The invention relates to the technical field of preparation of deuterated dimethyl sulfoxide, and provides a catalyst for preparing deuterated dimethyl sulfoxide, application of the catalyst and a preparation method of deuterated dimethyl sulfoxide, and the catalyst is a highly crystallized MOF material (ZIF-7)-on-(Co-BTC); the preparation method of the deuterated dimethyl sulfoxide comprises the following steps: (1) taking deuterium gas and sulfur as raw materials to react at high temperature, and then cooling to room temperature to obtain deuterium sulfide; (2) taking the deuterium sulfide obtained in the step (1), deuterated methanol and gamma-Al2O3 as raw materials, and reacting at high temperature to obtain deuterated dimethyl sulfide; (3) the deuterated dimethyl sulfide obtained in the step (2) is used as a raw material, in the presence of a (ZIF-7)-on-(Co-BTC) catalyst, oxygen and nitrogen dioxide, deuterated dimethyl sulfoxide is obtained through oxidation, and then high-purity deuterated dimethyl sulfoxide is obtained through rectification; the high-purity and large-scale production of the deuterated dimethyl sulfoxide can be met, and the deuteration degree of the deuterated dimethyl sulfoxide can reach 99.8% or above.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of deuterated dimethyl sulfoxide, and in particular, to a catalyst for preparing deuterated dimethyl sulfoxide, an application thereof, and a preparation method of deuterated dimethyl sulfoxide. Background Art

[0002] Deuterated dimethyl sulfoxide (DMSO-d6) is the most commonly used deuterated detection solvent for nuclear magnetic resonance spectroscopy (NMR) testing. Its core value lies in that the deuteron ( 1 H) has a spin quantum number of 1 and does not interfere with the hydrogen spectrum signal of the sample, thus significantly improving the spectral resolution. In addition, in drug development, as a polar aprotic solvent, it can dissolve poorly soluble drug molecules and extend the drug metabolic half-life through the isotope effect. At the same time, in photochemical reactions and protein structure research, DMSO-d6 also shows special research value.

[0003] Its preparation method mainly uses ordinary DMSO and heavy water (D2O) as raw materials, and realizes hydrogen-deuterium exchange through multiple heating-dehydration cycles under alkaline conditions. However, this method has a low deuteration degree and produces many side reactions. The deuteration degree of a single exchange reaction is limited. It often requires multiple heavy water cycles and alkali catalysis to promote the isotope exchange equilibrium, and multiple vacuum distillations and recrystallizations are required to remove undeuterated impurities. Moreover, due to the strong hygroscopicity and skin permeability of DMSO, experimental personnel need to wear protective equipment and operate in a fume hood. Waste liquid treatment also needs to follow the isotope waste management specifications; or ordinary DMSO is exposed to a deuterium (D2) atmosphere to achieve deuteration through a low-temperature reaction. However, this method requires high equipment requirements and the cost of deuterium is expensive, so industrial applications are less.

[0004] In summary, the current domestic preparation methods of deuterated dimethyl sulfoxide are very limited, the product purity is not ideal, and large-scale production cannot be achieved. Deuterated dimethyl sulfoxide products basically rely on imports. Therefore, how to meet the higher purity and large-scale production of deuterated dimethyl sulfoxide is particularly important. Summary of the Invention

[0005] The purpose of the present invention is to provide a catalyst for preparing deuterated dimethyl sulfoxide, an application thereof, and a preparation method of deuterated dimethyl sulfoxide, which can meet the higher purity and large-scale production of deuterated dimethyl sulfoxide, and the deuteration degree of deuterated dimethyl sulfoxide can reach more than 99.8%.

[0006] The embodiments of the present invention are achieved by the following technical solutions:

[0007] A preparation method of a (ZIF-7)-on-(Co-BTC) catalyst, comprising the following steps:

[0008] S1. Using cobalt nitrate hexahydrate and trimesic acid as raw materials, reacting in N,N-dimethylformamide in a polytetrafluoroethylene high-pressure reactor at 150 - 250 °C for 10 - 15 hours to obtain Co-BTC;

[0009] S2. Mix the obtained Co-BTC and the modifier polyvinylpyrrolidone evenly in N,N-dimethylformamide, then add benzimidazole and continue stirring until it is completely dissolved to obtain a mixed solution;

[0010] S3. Add zinc nitrate hexahydrate to the obtained mixed solution, heat and stir, and then centrifuge and wash to obtain the catalyst (ZIF-7)-on-(Co-BTC).

[0011] A preparation method of deuterated dimethyl sulfoxide, comprising the following steps:

[0012] (1) Using deuterium and sulfur as raw materials (mass ratio 1:10 - 15), reacting at 400 - 450 °C for 3 - 5 h, and then cooling to room temperature to obtain deuterium sulfide;

[0013] (2) Using the deuterium sulfide, deuterated methanol and γ-Al2O3 obtained in step (1) as raw materials (mass ratio: 1:1 - 3:0.01 - 0.05), reacting at 240 - 370 °C for 3 - 5 h, and then obtaining deuterated dimethyl sulfide and heavy water through liquid separation and rectification;

[0014] Among them, heavy water can be used for electrolyzing to prepare the deuterium gas required in step (1) and the deuterated methanol required in step (2);

[0015] (3) Using the deuterated dimethyl sulfide obtained in step (2) as raw material, in the presence of the catalyst (ZIF-7)-on-(Co-BTC), oxygen and nitrogen dioxide prepared above, performing an oxidation reaction at 25 - 100 °C for 10 - 15 h to obtain deuterated dimethyl sulfoxide, and then obtaining high-purity deuterated dimethyl sulfoxide through rectification; among them, the mass ratio of deuterated dimethyl sulfide to the catalyst is 1:0.2 - 0.6.

[0016] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0017] 1. The present invention synthesizes a suitable MOF material catalyst for the preparation of deuterated dimethyl sulfoxide, which can achieve the self-assembly of metal ions and ligands in a relatively short time to form a highly crystalline MOF material, (ZIF-7)-on-(Co-BTC); it can effectively maintain the integrity of the crystal structure, reduce the generation of crystal defects, and have a higher crystallinity. When used in the production of deuterated dimethyl sulfoxide, it can be recycled after the reaction is complete; in addition, the catalyst of the present invention is prepared under normal temperature and pressure or medium and low energy conditions, with low energy consumption, and this method can reduce the use of solvents, meeting the requirements of green chemistry. Most importantly, when the present invention uses (ZIF-7)-on-(Co-BTC) as a catalyst to synthesize deuterated dimethyl sulfoxide, compared with traditional catalysts (such as γ-Al2O3), its catalytic effect is higher. This is mainly because through the synergistic effect of the two MOF materials, the stability and recyclability of the catalyst can be significantly improved; the metal nodes and ligands of MOF can be used as microenvironment units to directly regulate the reaction performance of catalytic sites, enrich reactants, and make intermediates more stable; in addition, through the high specific surface area and porous structure of MOF, the composite MOF material (ZIF-7)-on-(Co-BTC) can maintain high catalytic performance while significantly reducing the cost of the catalyst. Moreover, the catalyst of the present invention itself has more active sites, which can make the process of converting deuterated dimethyl sulfide into deuterated dimethyl sulfoxide smoother, shorter in time, higher in efficiency, and greater in reaction degree. Therefore, using this catalyst can obtain deuterated dimethyl sulfoxide with higher purity and larger yield.

[0018] 2. The deuteration degree of deuterated dimethyl sulfoxide prepared by the preparation method of deuterated dimethyl sulfoxide provided by the present invention in different batches can reach more than 99.8%, and heavy water can be obtained simultaneously and directly returned to be used as the raw material required in this preparation method, greatly reducing the overall cost required for the preparation method. Detailed implementation manners

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely below. Those not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments not indicated by the manufacturer are all conventional products that can be obtained through commercial purchase.

[0020] (ZIF-7)-on-(Co-BTC) is prepared as shown in Examples 1-9:

[0021] Example 1

[0022] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic matter, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0023] Step 2: Mix and stir evenly 0.5 g of Co-BTC obtained in Step 1 and polyvinylpyrrolidone (50 mg) in 200 g of N,N-dimethylformamide solvent. Immediately add 2 g of benzimidazole and continue stirring until it is completely dissolved in the solution;

[0024] Step 3: Add 1 g of zinc nitrate hexahydrate to the mixed solution obtained in Step 2, heat to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0025] Example 2

[0026] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic matter, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0027] Step 2: Mix and stir evenly 1 g of Co-BTC obtained in Step 1 and polyvinylpyrrolidone (50 mg) in 200 g of N,N-dimethylformamide solvent. Immediately add 2 g of benzimidazole and continue stirring until it is completely dissolved in the solution;

[0028] Step 3: Add 1 g of zinc nitrate hexahydrate to the mixed solution obtained in Step 2, heat to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0029] Example 3

[0030] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic matter, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0031] Step 2: Mix and stir evenly 1.5 g of Co-BTC obtained in Step 1 and polyvinylpyrrolidone (50 mg) in 200 g of N,N-dimethylformamide solvent. Immediately add 2 g of benzimidazole and continue stirring until it is completely dissolved in the solution;

[0032] Step 3: Add zinc nitrate hexahydrate (1 g) to the mixed solution obtained in Step 2, heat it to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0033] Example 4

[0034] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic substance, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0035] Step 2: Mix and stir 0.5 g of Co-BTC obtained in Step 1 and polyvinylpyrrolidone (50 mg) evenly in the solvent of N,N-dimethylformamide (200 g). Then add benzimidazole (3 g) and continue stirring until it is completely dissolved in the solution;

[0036] Step 3: Add zinc nitrate hexahydrate (1 g) to the mixed solution obtained in Step 2, heat it to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0037] Example 5

[0038] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic substance, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0039] Step 2: Mix and stir 1 g of Co-BTC obtained in Step 1 and polyvinylpyrrolidone (50 mg) evenly in the solvent of N,N-dimethylformamide (200 g). Then add benzimidazole (3 g) and continue stirring until it is completely dissolved in the solution;

[0040] Step 3: Add zinc nitrate hexahydrate (1 g) to the mixed solution obtained in Step 2, heat it to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0041] Example 6

[0042] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic substance, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0043] Step 2: Mix the Co-BTC (1.5 g) obtained in Step 1 with polyvinylpyrrolidone (50 mg) in N,N-dimethylformamide (200 g) solvent and stir evenly. Then add benzimidazole (3 g) and continue stirring until it is completely dissolved in the solution;

[0044] Step 3: Add zinc nitrate hexahydrate (1 g) to the mixed solution obtained in Step 2, heat to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0045] Example 7

[0046] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic substance, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0047] Step 2: Mix the Co-BTC (0.5 g) obtained in Step 1 with polyvinylpyrrolidone (50 mg) in N,N-dimethylformamide (200 g) solvent and stir evenly. Then add benzimidazole (4 g) and continue stirring until it is completely dissolved in the solution;

[0048] Step 3: Add zinc nitrate hexahydrate (1 g) to the mixed solution obtained in Step 2, heat to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0049] Example 8

[0050] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic substance, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0051] Step 2: Mix the Co-BTC (1 g) obtained in Step 1 with polyvinylpyrrolidone (50 mg) in N,N-dimethylformamide (200 g) solvent and stir evenly. Then add benzimidazole (4 g) and continue stirring until it is completely dissolved in the solution;

[0052] Step 3: Add zinc nitrate hexahydrate (1 g) to the mixed solution obtained in Step 2, heat to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0053] Example 9

[0054] Step 1: Using cobalt nitrate hexahydrate (1 g) as the matrix, trimesic acid (0.3 g) as the organic substance, and N,N-dimethylformamide (30 mL) as the solvent, react in a polytetrafluoroethylene autoclave at 200 °C for 12 hours to obtain Co-BTC;

[0055] Step 2: Mix and stir evenly 1.5 g of Co-BTC obtained in Step 1 and 50 mg of polyvinylpyrrolidone in 200 g of N,N-dimethylformamide solvent. Then add 4 g of benzimidazole and continue stirring until it is completely dissolved in the solution;

[0056] Step 3: Add 1 g of zinc nitrate hexahydrate to the mixed solution obtained in Step 2, heat to 50 °C, and stir for 48 h. After centrifugal washing, the catalyst (ZIF-7)-on-(Co-BTC) can be obtained.

[0057] The preparation of deuterated dimethyl sulfoxide is shown in Examples 10 - 18:

[0058] Example 10

[0059] Step 1: Pass 1 g of deuterium gas into a stainless-steel autoclave containing 10 g of sulfur, then gradually heat to 400 °C. After reacting for 5 h, cool to room temperature and collect the gas, which is deuterium sulfide;

[0060] Step 2: Pass 1 g of deuterium sulfide obtained in Step 1 into a stainless-steel autoclave containing 1.5 g of deuterated methanol and 0.01 g of γ-Al2O3, then gradually heat to 350 °C. After reacting for 5 h, cool to room temperature. Through liquid separation and rectification, deuterated dimethyl sulfide and heavy water are obtained respectively;

[0061] Step 3: Pass oxygen, nitrogen dioxide, and 0.2 g of (ZIF-7)-on-(Co-BTC) prepared in Example 1 into a stainless-steel autoclave containing 1 g of deuterated dimethyl sulfide obtained in Step 2, then gradually heat to 50 °C. After reacting for 12 h, cool to room temperature, and obtain deuterated dimethyl sulfoxide through rectification.

[0062] Example 11

[0063] Step 1: Pass 1 g of deuterium gas into a stainless-steel autoclave containing 10 g of sulfur, then gradually heat to 400 °C. After reacting for 5 h, cool to room temperature and collect the gas, which is deuterium sulfide;

[0064] Step 2: Pass 1 g of deuterium sulfide obtained in Step 1 into a stainless-steel autoclave containing 1.5 g of deuterated methanol and 0.01 g of γ-Al2O3, then gradually heat to 350 °C. After reacting for 5 h, cool to room temperature. Through liquid separation and rectification, deuterated dimethyl sulfide and heavy water are obtained respectively;

[0065] Step 3: Introduce oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.4 g) prepared in Example 2 into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2. Then gradually heat the mixture to 50 °C and react for 12 h. After cooling to room temperature, deuterated dimethyl sulfoxide is obtained through rectification.

[0066] Example 12

[0067] Step 1: Introduce deuterium gas (1 g) into a stainless-steel reactor containing sulfur (10 g). Then gradually heat the mixture to 400 °C and react for 5 h. After cooling to room temperature, collect the gas, which is deuterium sulfide.

[0068] Step 2: Introduce the deuterium sulfide (1 g) obtained in Step 1 into a stainless-steel reactor containing deuterated methanol (1.5 g) and γ-Al2O3 (0.01 g). Then gradually heat the mixture to 350 °C and react for 5 h. After cooling to room temperature, deuterated dimethyl sulfide and heavy water are obtained through liquid separation and rectification respectively.

[0069] Step 3: Introduce oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.6 g) prepared in Example 3 into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2. Then gradually heat the mixture to 50 °C and react for 12 h. After cooling to room temperature, deuterated dimethyl sulfoxide is obtained through rectification.

[0070] Example 13

[0071] Step 1: Introduce deuterium gas (1 g) into a stainless-steel reactor containing sulfur (15 g). Then gradually heat the mixture to 420 °C and react for 5 h. After cooling to room temperature, collect the gas, which is deuterium sulfide.

[0072] Step 2: Introduce the deuterium sulfide (1 g) obtained in Step 1 into a stainless-steel reactor containing deuterated methanol (2 g) and γ-Al2O3 (0.01 g). Then gradually heat the mixture to 350 °C and react for 5 h. After cooling to room temperature, deuterated dimethyl sulfide and heavy water are obtained through liquid separation and rectification respectively.

[0073] Step 3: Introduce oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.2 g) prepared in Example 4 into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2. Then gradually heat the mixture to 70 °C and react for 12 h. After cooling to room temperature, deuterated dimethyl sulfoxide is obtained through rectification.

[0074] Example 14

[0075] Step 1: Introduce deuterium gas (1 g) into a stainless-steel reactor containing sulfur (15 g), then gradually raise the temperature to 420 °C. After reacting for 5 h, cool to room temperature and collect the gas, which is deuterium sulfide;

[0076] Step 2: Introduce the deuterium sulfide (1 g) obtained in Step 1 into a stainless-steel reactor containing deuterated methanol (2 g) and γ-Al2O3 (0.01 g), then gradually raise the temperature to 350 °C. After reacting for 5 h, cool to room temperature. Through liquid separation and rectification, deuterated dimethyl sulfide and heavy water are obtained respectively;

[0077] Step 3: Introduce oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.4 g) prepared in Example 5 into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2, then gradually raise the temperature to 70 °C. After reacting for 12 h, cool to room temperature. Through rectification, deuterated dimethyl sulfoxide is obtained.

[0078] Example 15

[0079] Step 1: Introduce deuterium gas (1 g) into a stainless-steel reactor containing sulfur (15 g), then gradually raise the temperature to 420 °C. After reacting for 5 h, cool to room temperature and collect the gas, which is deuterium sulfide;

[0080] Step 2: Introduce the deuterium sulfide (1 g) obtained in Step 1 into a stainless-steel reactor containing deuterated methanol (2 g) and γ-Al2O3 (0.01 g), then gradually raise the temperature to 350 °C. After reacting for 5 h, cool to room temperature. Through liquid separation and rectification, deuterated dimethyl sulfide and heavy water are obtained respectively;

[0081] Step 3: Introduce oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.6 g) prepared in Example 6 into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2, then gradually raise the temperature to 70 °C. After reacting for 12 h, cool to room temperature. Through rectification, deuterated dimethyl sulfoxide is obtained.

[0082] Example 16

[0083] Step 1: Introduce deuterium gas (1 g) into a stainless-steel reactor containing sulfur (12 g), then gradually raise the temperature to 400 °C. After reacting for 5 h, cool to room temperature and collect the gas, which is deuterium sulfide;

[0084] Step 2: Introduce the deuterium sulfide (1 g) obtained in Step 1 into a stainless-steel reactor containing deuterated methanol (1.8 g) and γ-Al2O3 (0.01 g), then gradually raise the temperature to 300 °C. After reacting for 10 h, cool to room temperature. Through liquid separation and rectification, deuterated dimethyl sulfide and heavy water are obtained respectively;

[0085] Step 3: Oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.2 g) prepared in Example 7 were introduced into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2. Then, the temperature was gradually raised to 90 °C. After reacting for 12 h, it was cooled to room temperature, and deuterated dimethyl sulfoxide was obtained by distillation.

[0086] Example 17

[0087] Step 1: Deuterium gas (1 g) was introduced into a stainless-steel reactor containing sulfur (12 g). Then, the temperature was gradually raised to 400 °C. After reacting for 5 h, it was cooled to room temperature, and the gas was collected as deuterium sulfide.

[0088] Step 2: The deuterium sulfide (1 g) obtained in Step 1 was introduced into a stainless-steel reactor containing deuterated methanol (1.8 g) and γ-Al2O3 (0.01 g). Then, the temperature was gradually raised to 300 °C. After reacting for 10 h, it was cooled to room temperature, and deuterated dimethyl sulfide and heavy water were obtained by liquid separation and distillation, respectively.

[0089] Step 3: Oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.4 g) prepared in Example 8 were introduced into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2. Then, the temperature was gradually raised to 90 °C. After reacting for 12 h, it was cooled to room temperature, and deuterated dimethyl sulfoxide was obtained by distillation.

[0090] Example 18

[0091] Step 1: Deuterium gas (1 g) was introduced into a stainless-steel reactor containing sulfur (12 g). Then, the temperature was gradually raised to 400 °C. After reacting for 5 h, it was cooled to room temperature, and the gas was collected as deuterium sulfide.

[0092] Step 2: The deuterium sulfide (1 g) obtained in Step 1 was introduced into a stainless-steel reactor containing deuterated methanol (1.8 g) and γ-Al2O3 (0.01 g). Then, the temperature was gradually raised to 300 °C. After reacting for 10 h, it was cooled to room temperature, and deuterated dimethyl sulfide and heavy water were obtained by liquid separation and distillation, respectively.

[0093] Step 3: Oxygen, nitrogen dioxide, and (ZIF-7)-on-(Co-BTC) (0.6 g) prepared in Example 9 were introduced into a stainless-steel reactor containing the deuterated dimethyl sulfide (1 g) obtained in Step 2. Then, the temperature was gradually raised to 90 °C. After reacting for 12 h, it was cooled to room temperature, and deuterated dimethyl sulfoxide was obtained by distillation.

[0094] Comparative Example 1

[0095] The difference between this comparative example and Example 10 is that the catalyst in Step (3) is a titanium-silicalite molecular sieve catalyst.

[0096] Experimental Example

[0097] The purity and deuteration degree (characterized by high-resolution mass spectrometry) of the deuterated dimethyl sulfoxide prepared in Examples 10-18 and Comparative Example 1 were tested and analyzed, and the results are shown in Table 1.

[0098] Table 1 - Deuteration degree results of deuterated dimethyl sulfoxide prepared in Examples 10-18 and Comparative Example 1

[0099] Degree of deuteration (%) Purity (%) Example 10 99.9 95.4 Example 11 99.9 95.3 Example 12 99.9 95.5 Example 13 99.9 95.4 Example 14 99.9 95.4 Example 15 99.9 95.3 Example 16 99.9 95.5 Example 17 99.9 95.4 Example 18 99.9 95.3 Comparative Example 1 89 85

[0100] It can be seen that the deuteration degree of different batches of deuterated dimethyl sulfoxide prepared by the preparation method of the present invention can reach over 99.8%. Moreover, after the catalytic action of the highly crystalline MOF material (ZIF-7)-on-(Co-BTC), the efficiency of converting deuterated dimethyl sulfide into deuterated dimethyl sulfoxide is higher, and the reaction degree is greater. Therefore, the deuteration degree and purity of the obtained deuterated dimethyl sulfoxide are higher, and it can be produced on a large scale.

[0101] 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 can have various changes and modifications. Any modification, equivalent replacement, improvement, 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 (ZIF-7)-on-(Co-BTC) catalyst, comprising the following steps: S1. Using cobalt nitrate hexahydrate and trimesic acid as raw materials, reacting in an organic solvent for a period of time to obtain Co-BTC; S2. Mixing the obtained Co-BTC with a modifier evenly in an organic solvent, then adding benzimidazole and continuing to stir until it is completely dissolved to obtain a mixed solution; S3. Adding zinc nitrate hexahydrate to the obtained mixed solution, heating, stirring, centrifuging and washing to obtain the catalyst (ZIF-7)-on-(Co-BTC).

2. The preparation method of the (ZIF-7)-on-(Co-BTC) catalyst according to claim 1, characterized in that, In S1, the reaction is carried out at 150-250 °C for 10-15 hours.

3. The preparation method of the (ZIF-7)-on-(Co-BTC) catalyst according to claim 1, characterized in that, In S2, the modifier is polyvinylpyrrolidone.

4. A (ZIF-7)-on-(Co-BTC) catalyst, characterized in that, Prepared by the preparation method described in any one of claims 1-3.

5. An application of the (ZIF-7)-on-(Co-BTC) catalyst prepared by the preparation method described in any one of claims 1-3 in the preparation of deuterated dimethyl sulfoxide.

6. A preparation method of deuterated dimethyl sulfoxide, characterized in that, Comprising the following steps: (1) Using deuterium and sulfur as raw materials, reacting at high temperature, and then cooling to room temperature to obtain deuterated hydrogen sulfide; (2) Using the deuterated hydrogen sulfide, deuterated methanol and γ-Al2O3 obtained in step (1) as raw materials, reacting at high temperature for a period of time to obtain deuterated dimethyl sulfide; (3) Using the deuterated dimethyl sulfide obtained in step (2) as raw material, in the presence of the (ZIF-7)-on-(Co-BTC) catalyst, oxygen and nitrogen dioxide prepared by the preparation method described in any one of claims 1-3, oxidizing at a certain temperature to obtain deuterated dimethyl sulfoxide, and then obtaining high-purity deuterated dimethyl sulfoxide by rectification.

7. The preparation method of deuterated dimethyl sulfoxide according to claim 6, characterized in that, In step (1), the mass ratio of deuterium to sulfur is 1:10-15; and the reaction is carried out at 400-450 °C for 3-5 h.

8. The preparation method of deuterated dimethyl sulfoxide according to claim 6, characterized in that, In step (2), the mass ratio of deuterated hydrogen sulfide, deuterated methanol and γ-Al2O3 is: 1:1-3:0.01-0.05; and the reaction is carried out at 240-370 °C for 3-5 h.

9. The preparation method of deuterated dimethyl sulfoxide according to claim 6, characterized in that, In step (3), the mass ratio of deuterated dimethyl sulfide to the catalyst is 1:0.2-0.

6.

10. The preparation method of deuterated dimethyl sulfoxide according to claim 6, wherein In step (3), the oxidation reaction is carried out at 25-100 °C for 10-15 h.