β-UO3 catalyst prepared from depleted uranium for selective catalytic oxidation of aniline or its derivatives
By preparing β-UO3 catalyst from depleted UF6 for the oxidation of aniline or its derivatives, the problem of safe disposal and reuse of depleted uranium waste was solved, and the efficient preparation of 1-diphenyldiazene oxide or its derivatives was achieved, reducing costs and pollution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- LANZHOU UNIV
- Filing Date
- 2024-03-25
- Publication Date
- 2026-07-24
AI Technical Summary
In the existing technology, the problem of safe disposal and reuse of depleted uranium waste has not been effectively solved. Traditional catalysts have problems such as low selectivity, high cost and serious oxidant pollution in the preparation of 1-diphenyldiazeline oxide or its derivatives.
A β-UO3 catalyst was prepared using depleted UF6 as a raw material. The β-UO3 catalyst was prepared by dissolution and reprecipitation. Using β-UO3 as a catalyst, combined with mesitylene or other organic solvents and hydrogen peroxide as oxidants, aniline or its derivatives were catalyzed to oxidize aniline or its derivatives to synthesize 1-diphenyldiazene oxide or its derivatives.
This provides a low-cost, green, and efficient method for the reuse of depleted uranium. The catalyst has high activity and the target product yield is high. It reduces the cost of oxidants and the emission of toxic substances, which is in line with the concept of green chemistry.
Smart Images
Figure QLYQS_1 
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Abstract
Description
Technical Field
[0001] This invention relates to novel technologies for the utilization of depleted uranium, particularly the preparation of a β-UO3 catalyst from depleted UF6 as a raw material for the selective catalytic oxidation of aniline or its derivatives to prepare 1-diphenyldiazeline or its derivatives. Technical Background
[0002] Nuclear energy utilization is crucial to my country's national defense and the sustainable development of its energy system; however, it has also generated numerous problems and challenges. Large quantities of uranium-containing waste are generated during nuclear weapons research and development, nuclear facility operation, nuclear equipment use, and nuclear technology utilization, such as depleted uranium produced during uranium enrichment. 235 With a U content below 0.711%, there is essentially no radioactive hazard to humans. However, depleted uranium hexafluoride is chemically reactive and possesses a certain degree of chemical toxicity. A leak could damage the environment and surrounding organisms. Therefore, the safe disposal and reuse of such substances is a pressing issue that needs to be addressed in pollution prevention and control efforts.
[0003] Due to its large radius, the coordination number resulting from the participation of f orbitals in bonding interactions, and its unique coordination structure, uranium distinguishes itself from transition metals, exhibits complementary chemical reactivity with d-block transition elements, and displays electronic flexibility in multiple oxidation states from +II to +VI in both solution and solid states (see *Acs Catalysis*, 2019, Vol. 9, No. 6, 4719-4741). Therefore, uranium-characterized complexes have been explored for use in catalytic chemistry. In recent years, research on uranium oxides has been steadily increasing (see *Nature*, 2012, Vol. 335, No. 6073, 1184-1187), mainly involving uranium-containing oxides such as UO2, U3O8, and UO4·H2O. Gupta et al. immobilized uranyl ions in MCM-41 and photocatalyzed the conversion of methanol to carbon dioxide (see *Applied Catalysis B-Environmental*, 2004, No. 54, No. 3, 145-154). Taylor et al. used a co-precipitation method to synthesize a series of uranium-containing bimetallic oxides U / M (M = Mo, Sb, Fe, V, W) to study the complete and incomplete oxidation of toluene (see Catalysis Today, 2021, Vol. 363, 73-84).
[0004] 1-Diphenyldiazene oxide is not only a key component of natural compounds and functional materials, but it is also frequently used as a therapeutic agent, indicator, dye, pigment, chemical sensor, polymer, soft material, and photochemical switch, demonstrating extremely high application value (see *Acs Catalysis*, 2013, Vol. 3, No. 4, 478-486). The traditional method for synthesizing 1-diphenyldiazene oxide or its derivatives involves the selective reduction of nitrobenzene and its derivatives in the presence of a catalyst and a reducing agent. However, the low selectivity and high cost of the catalyst, as well as the high pollution, instability, and high cost of the reducing agent, have hindered industrial development. In recent years, chemists have discovered that directly catalytically oxidizing aniline or its derivatives under oxidant conditions to prepare 1-diphenyldiazene oxide or its derivatives is also a highly efficient method.
[0005] Based on the above background and in line with our research direction, we consider using uranium-based catalysts to catalyze the synthesis of traditional fine chemicals. This invention uses U3O8 as a raw material, dissolving and then precipitating it to synthesize a β-UO3 catalyst for the catalytic oxidation of aniline and its derivatives to 1-diphenyldiazene oxide or its derivatives. The preparation process of this catalyst is simple and convenient, with high reactivity. Furthermore, the method of directly catalyzing the synthesis of 1-diphenyldiazene oxide or its derivatives from aniline using β-UO3 has not been reported to date. From the perspective of environmental friendliness and sustainable development, this invention effectively solves the problem of safe disposal and reuse of depleted uranium; from the perspective of organic synthesis, it provides a completely new approach for synthesizing high-value-added fine chemicals. Summary of the Invention
[0006] This invention discovers that a β-UO3 catalyst prepared using U3O8 obtained from depleted UF6 as a raw material can catalytically oxidize aniline or its derivatives to form 1-diphenyldiazene oxide or its derivatives. Therefore, this invention not only provides a novel method for utilizing depleted uranium, but also proposes a low-cost, green, and efficient method for preparing 1-diphenyldiazene oxide or its derivatives. This method is simple, low-cost, and highly safe, aligning well with green and friendly chemistry principles. Specifically, it includes the following:
[0007] In a first aspect, the present invention provides a method for preparing a β-UO3 catalyst by simply dissolving and reprecipitating U3O8 obtained from depleted UF6 as a raw material.
[0008] Preferably, the catalyst preparation method includes the following steps:
[0009] (1) Preparation of (NH4)2U2O7: Weigh a specific mass of U3O8 prepared from depleted UF6 as raw material, place it in a container, heat and stir while adding concentrated nitric acid or concentrated hydrochloric acid to completely dissolve U3O8, then add an appropriate amount of deionized water to form a transparent uranyl salt solution, then add an appropriate amount of precipitant, and continue stirring for 5-8 hours. After that, separate the solid product, wash and dry it to obtain (NH4)2U2O7.
[0010] (2) Preparation of β-UO3: The precursor (NH4)2U2O7 was ground thoroughly in a mortar, then transferred to a clean porcelain boat and placed in a muffle furnace. β-UO3 was obtained by calcining at 500℃ for 5 hours at a heating rate of 10℃ / min. Its XRD crystal structure is shown in the attached figure. Figure 1 As shown.
[0011] Preferably, the aniline or its derivative has the structural formula shown in formula (I) below, and the 1-diphenyldiazeline oxide or its derivative has the structural formula shown in formula (II) below:
[0012]
[0013] R1-R5 are selected from any one of hydrogen, halogen, hydroxyl, sulfonic acid group, nitro group, substituted or unsubstituted straight-chain or branched alkyl, alkoxy, carbonyl, alkenyl, alkynyl, substituted or unsubstituted aryl, amide, and cyano groups, but are not limited to the above substituents.
[0014] Preferably, R1-R5 are selected from hydrogen, methyl, and chlorine, respectively.
[0015] Preferably, the aniline or its derivatives include: aniline, o-methylaniline, p-methylaniline, p-chloroaniline, o-chloroaniline, and m-chloroaniline.
[0016] In a second aspect, the present invention provides a method for preparing 1-diphenyldiazene oxide or its derivatives thereof, the method comprising: using aniline or its derivatives as shown in formula (I) as raw material, using mesitylene or a mixture of mesitylene and an organic solvent as reaction solvent, using β-UO3 as catalyst, and using hydrogen peroxide as oxidant, to catalytically oxidize and synthesize 1-diphenyldiazene oxide or its derivatives as shown in formula (II), wherein the organic solvent includes methanol, ethanol, and acetonitrile;
[0017]
[0018] R1-R5 are selected from any one of hydrogen, halogen, hydroxyl, sulfonic acid group, nitro group, substituted or unsubstituted straight-chain or branched alkyl, alkoxy, carbonyl, alkenyl, alkynyl, substituted or unsubstituted aryl, amide, cyano group, but are not limited to the above substituents.
[0019] Preferably, R1-R5 are selected from hydrogen, methyl, and chlorine, respectively.
[0020] Preferably, the aniline or its derivatives include: aniline, o-methylaniline, p-methylaniline, p-chloroaniline, o-chloroaniline, and m-chloroaniline.
[0021] Preferably, the ratio of the catalyst to aniline or its derivative is 1-20 mg: 0.1 mmol.
[0022] Preferably, the ratio of the catalyst to aniline or its derivative is 5-15 mg: 0.1 mmol.
[0023] Preferably, the ratio of the catalyst to aniline or its derivative is 10 mg: 0.1 mmol.
[0024] Preferably, the mass ratio of the reaction solvent to aniline or its derivative is 1-40:1.
[0025] Preferably, the mass ratio of the reaction solvent to aniline or its derivative is 5-20:1.
[0026] Preferably, the mass ratio of the reaction solvent to aniline or its derivative is 10:1.
[0027] Preferably, the reaction solvent is mesitylene.
[0028] Preferably, the catalyst is β-UO3.
[0029] Preferably, the method includes the following steps:
[0030] (1) Add aniline or its derivatives and β-UO3 to a reaction tube containing a reaction solvent;
[0031] (2) Add 0.5 mL of hydrogen peroxide to the reaction tube and react at 110 °C for 5 h;
[0032] (3) Filter, distill and recrystallize to obtain 1-diphenyldiazene oxide or its derivatives.
[0033] Preferably, the volume of the hydrogen peroxide is 0.1-1.0 mL.
[0034] Preferably, the volume of the hydrogen peroxide is 0.5 mL.
[0035] Preferably, the reaction temperature is 50-150°C.
[0036] Preferably, the reaction temperature is 110°C.
[0037] Preferably, the reaction time is 1-20 hours.
[0038] Preferably, the reaction time is 5 hours.
[0039] Compared with the prior art, the technical solution of the present invention has the following advantages:
[0040] (1) This invention uses depleted uranium waste as raw material to prepare catalyst, which effectively solves the problem of safe disposal and reuse of depleted uranium in my country’s nuclear energy utilization.
[0041] (2) The aniline or its derivatives used in this invention are common basic raw materials in industry and have low cost;
[0042] (3) This invention uses inexpensive and readily available hydrogen peroxide as an oxidant. Compared with the traditional method of using peracetic acid, Pb(OAc)4, Hg(OAc)2, BaMnO4 and hydrogen peroxide as oxidants, it significantly reduces the cost of oxidants and solves the problems of toxic substance emissions and production safety caused by the use of oxidants.
[0043] (4) The method described in this invention can catalytically oxidize aniline or its derivatives to the corresponding 1-diphenyldiazeline or its derivatives, with good specificity and high yield of the target product. Attached Figure Description
[0044] Figure 1 X-ray diffraction crystal structure diagram of β-UO3;
[0045] Figure 2 Mass spectrum of 1-diphenyldiazene oxide synthesized by the method described in Example 1;
[0046] Figure 3 Mass spectrum of 1-diphenyldiazene oxide synthesized by the method described in Example 2;
[0047] Figure 4 Mass spectrum of 1-diphenyldiazene oxide synthesized by the method described in Example 3;
[0048] Figure 5 Mass spectrum of 1-diphenyldiazene oxide synthesized by the method described in Example 4;
[0049] Figure 6 Mass spectrum of 1-diphenyldiazene oxide synthesized by the method described in Example 5;
[0050] Figure 7 Mass spectrum of 1-diphenyldiazene oxide synthesized by the method described in Example 6;
[0051] Figure 8 Mass spectrum of 2,2'-dimethyl-1-diphenyldiazene oxide synthesized by the method described in Example 7;
[0052] Figure 9Mass spectrum of 4,4'-dimethyl-1-diphenyldiazene oxide synthesized by the method described in Example 7;
[0053] Figure 10 Mass spectrum of the product 4,4'-dichloro-1-diphenyldiazene synthesized by the method described in Example 7;
[0054] Figure 11 Mass spectrum of the product 3,3'-dichloro-1-diphenyldiazene synthesized by the method described in Example 7;
[0055] Figure 12 Mass spectrum of 2,2'-dichloro-1-diphenyldiazene synthesized by the method described in Example 7. Detailed Implementation
[0056] 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.
[0057] Example 1: Synthesis of 1-diphenyldiazene oxide using different reaction solvents
[0058] 1. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0059] 2. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g aniline, 0.867 g mesitylene and methanol (mass ratio 1:1), add 0.5 mL of hydrogen peroxide at 110 °C, react for 5 h, then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0060] 3. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g aniline, 0.867 g mesitylene and ethanol (mass ratio 1:1), add 0.5 mL of hydrogen peroxide at 110 °C, react for 5 h, then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0061] 4. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g aniline, 0.867 g mesitylene and acetonitrile (mass ratio 1:1), add 0.5 mL of hydrogen peroxide at 110 °C, react for 5 h, then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0062] The yields of 1-diphenyldiazene oxide obtained by the preparation methods described in 1-4 above were calculated, and the results are shown in Table 1 below:
[0063] Table 1. Process parameters and yield of the product 1-diphenyldiazepine as described in Example 1.
[0064]
[0065] The mass spectrum of the main product synthesized in the above reaction is shown below. Figure 1 The results are shown in Figure 1. (The mass spectra of the main products of the above four 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 indicate that aniline can be catalytically synthesized into 1-diphenyldiazepine oxide using mesitylene or a mixture of mesitylene and an organic solvent (mesitylene + methanol, mesitylene + ethanol, mesitylene + acetonitrile) as the reaction solvent and β-UO3 as the catalyst; and the yield of 1-diphenyldiazepine oxide obtained by using mesitylene as the reaction solvent can reach up to 92%.
[0066]
[0067] Example 2: Synthesis of 1-diphenyldiazene oxide with different amounts of reaction solvent
[0068] 1. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.434 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0069] 2. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0070] 3. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 1.301 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0071] 4. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 1.734 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0072] 5. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 2.168 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0073] The yields of 1-diphenyldiazene oxide obtained by the preparation methods described in 1-5 above were calculated, and the results are shown in Table 2 below:
[0074] Table 2. Process parameters and yield of the product 1-diphenyldiazepine as described in Example 2.
[0075]
[0076] The mass spectrum of the main product obtained from 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 is shown in Formula 1 below. The above results indicate that using mesitylene as the reaction solvent (mesotriene to aniline mass ratio of 1-50:1), hydrogen peroxide as the oxidant, and β-UO3 as the catalyst, aniline can be catalytically synthesized into 1-diphenyldiazene oxide; simultaneously, when the mass ratio of mesitylene to aniline is 10-40:1, the yield of 1-diphenyldiazene oxide obtained is above 80%, and when the mass ratio of mesitylene to aniline is 18:1, the yield of 1-diphenyldiazene oxide obtained is as high as 92%.
[0077]
[0078] Example 3: Synthesis of 1-diphenyldiazene oxide at different reaction temperatures
[0079] 1. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 50 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0080] 2. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 60 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0081] 3. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 70 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0082] 4. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 80 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0083] 5. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 90 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0084] 6. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 100 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0085] 7. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0086] 8. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 120 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0087] 9. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 130 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0088] 10. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 140 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0089] 11. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 150 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0090] The yields of 1-diphenyldiazene oxide obtained by the preparation methods described in 1-11 above were calculated, and the results are shown in Table 3 below:
[0091] Table 3. Process parameters and yield of the product 1-diphenyldiazepine as described in Example 3.
[0092]
[0093] The mass spectrum of the main product obtained from the above reaction is shown below. Figure 3 As shown (the mass spectra of the main products of the above 11 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 of 50-150℃, using mesitylene as the reaction solvent, hydrogen peroxide as the oxidant, and β-UO3 as the catalyst, aniline can be catalytically synthesized into 1-diphenyldiazepine oxide; simultaneously, at reaction temperatures of 80-150℃, the yield of 1-diphenyldiazepine oxide obtained is above 70%; and at reaction temperatures above 110℃, the yield of 1-diphenyldiazepine oxide obtained can reach as high as 92%.
[0094]
[0095] Example 4: Synthesis of 1-diphenyldiazene oxide with different reaction times
[0096] 1. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 1 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0097] 2. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 2 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0098] 3. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 3 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0099] 4. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0100] 5. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 12 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0101] 6. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g aniline and 0.867 g mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 20 h. Then, filter, distill, and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0102] The yields of 1-diphenyldiazene oxide obtained by the preparation methods described in 1-5 above were calculated, and the results are shown in Table 4 below:
[0103] Table 4. Process parameters and yield of the product 1-diphenyldiazepine as described in Example 4.
[0104]
[0105]
[0106] 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 6 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 1-20 h, using mesitylene as the reaction solvent, hydrogen peroxide as the oxidant, and β-UO3 as the catalyst, aniline can be catalytically synthesized into 1-diphenyldiazepine oxide; simultaneously, the yield of 1-diphenyldiazepine oxide obtained from the reaction is above 80% when the reaction time is 3-20 h; and the highest yield of 1-diphenyldiazepine oxide obtained from the reaction can reach 92% when the reaction time is 5 h.
[0107]
[0108] Example 5: Synthesis of 1-diphenyldiazene oxide with different volumes of hydrogen peroxide
[0109] 1. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.1 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0110] 2. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.2 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0111] 3. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.3 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0112] 4. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0113] 5. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.8 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0114] 6. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 1.0 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0115] The yields of 1-diphenyldiazene oxide obtained by the preparation methods described in 1-6 above were calculated, and the results are shown in Table 5 below:
[0116] Table 5. Process parameters and yield of the product 1-diphenyldiazepine as described in Example 5.
[0117]
[0118] 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 6 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 hydrogen peroxide volume of 0.1-1.0 mL, using mesitylene as the reaction solvent, hydrogen peroxide as the oxidant, and β-UO3 as the catalyst, aniline can be catalytically synthesized into 1-diphenyldiazepine oxide; when the hydrogen peroxide volume is 0.3-0.8 mL, the yield of 1-diphenyldiazepine oxide obtained from the reaction is above 70%; and when the hydrogen peroxide volume is 0.5 mL, the yield of 1-diphenyldiazepine oxide obtained from the reaction can reach as high as 92%.
[0119]
[0120] Example 6: Synthesis of 1-diphenyldiazene oxide with different catalyst addition amounts
[0121] 1. Add 5.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0122] 2. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0123] 3. Add 15.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0124] 4. Add 18.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g aniline and 0.867 g mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then, filter, distill, and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0125] 5. Add 20.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0126] 6. Add 22.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0465 g of aniline and 0.867 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then filter, distill and recrystallize to obtain the product 1-diphenyldiazene oxide.
[0127] The yields of 1-diphenyldiazene oxide obtained by the preparation methods described in 1-6 above were calculated, and the results are shown in Table 6 below:
[0128] Table 6 shows the process parameters and yield of the product 1-diphenyldiazepine as described in Example 6.
[0129]
[0130] 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 6 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 mesitylene is used as the reaction solvent, hydrogen peroxide as the oxidant, and β-UO3 as the catalyst, and the ratio of catalyst to aniline or its derivative is 1-22 mg:0.1 mmol, aniline can be catalyzed to synthesize 1-diphenyldiazepine oxide; and when the ratio of catalyst to aniline or its derivative is 5-20 mg:0.1 mmol, the yield of 1-diphenyldiazepine oxide obtained is higher than 70%; simultaneously, when the ratio of catalyst to aniline or its derivative is 8-10 mg:0.1 mmol, the yield of 1-diphenyldiazepine oxide obtained is as high as 90% or more.
[0131]
[0132] Example 7: Synthesis of 1-diphenyldiazene oxide derivatives using different aniline derivatives
[0133] 1. 10.0 mg of β-UO3 catalyst was added to a 10 mL reaction tube, followed by 0.0535 g of o-methylaniline and 0.867 g of mesitylene. 0.5 mL of hydrogen peroxide was added at 110 °C, and the reaction was allowed to proceed for 5 h. The mixture was then filtered, distilled, and recrystallized to obtain the product 2,2'-dimethyl-1-diphenyldiazene oxide. The mass spectrum of the product is shown below. Figure 7 As shown, the structural formula is shown in Equation 2 below.
[0134]
[0135] 2. 10.0 mg of β-UO3 catalyst was added to a 10 mL reaction tube, followed by 0.0535 g of p-methylaniline and 0.867 g of mesitylene. 0.5 mL of hydrogen peroxide was added at 110 °C, and the reaction was allowed to proceed for 5 h. The mixture was then filtered, distilled, and recrystallized to obtain the product 3,3'-dimethyl-1-diphenyldiazene oxide. The mass spectrum of the product is shown below. Figure 8 As shown, the structural formula is shown in Equation 3 below.
[0136]
[0137] 3. 10.0 mg of β-UO3 catalyst was added to a 10 mL reaction tube, followed by 0.0635 g of p-chloroaniline and 1.30 g of mesitylene. 0.5 mL of hydrogen peroxide was added at 110 °C, and the reaction was allowed to proceed for 5 h. The mixture was then filtered, distilled, and recrystallized to obtain the product 4,4'-dimethyl-1-diphenyldiazene oxide. The mass spectrum of the product is shown below. Figure 9 As shown, the structural formula is shown in Equation 4 below.
[0138]
[0139] 4. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0635 g of m-chloroaniline and 1.30 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then, filter, distill, and recrystallize to obtain the product 4,4'-dichloro-1-diphenyldiazene oxide. The mass spectrum of the product is shown below. Figure 10 As shown, the structural formula is shown in Equation 5 below.
[0140]
[0141] 5. Add 10.0 mg of β-UO3 catalyst to a 10 mL reaction tube, then add 0.0860 g of o-chloroaniline and 2.601 g of mesitylene. Add 0.5 mL of hydrogen peroxide at 110 °C and react for 5 h. Then, filter, distill, and recrystallize to obtain the product 4,4'-dibromo-1-diphenyldiazene oxide. The mass spectrum of the product is shown below. Figure 11 As shown, the structural formula is shown in Equation 6 below.
[0142]
[0143] The yields of the 1-diphenyldiazene oxide derivatives obtained by the preparation methods described in 1-5 above were calculated, and the results are shown in Table 7 below:
[0144] Table 7. Process parameters and product yield of the preparation method described in Example 7.
[0145]
[0146]
[0147] The mass spectra of the main products in reactions 1-5 above are as follows: Figure 7-11 As shown above, the results indicate that using mesitylene as the reaction solvent, hydrogen peroxide as the oxidant, and β-UO3 as the catalyst, 2,2'-dimethyl-1-diphenyldiazepine can be catalytically synthesized from o-methylaniline with a yield of 75%; 3,3'-dimethyl-1-diphenyldiazepine can be catalytically synthesized from p-methylaniline with a yield of 82%; 4,4'-dichloro-1-diphenyldiazepine can be catalytically synthesized from p-chloroaniline with a yield of 92%; 3,3'-dichloro-1-diphenyldiazepine can be catalytically synthesized from m-chloroaniline with a yield of 95%; and 2,2'-dichloro-1-diphenyldiazepine can be catalytically synthesized from o-chloroaniline with a yield of 97%. Therefore, the method of the present invention can catalytically synthesize 1-diphenyldiazepine or its derivatives from aniline or its derivatives, and the yield of the target product is high.
[0148] 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. A method for preparing 1-diphenyldiazene oxide by catalytic oxidation of aniline, characterized in that, Using aniline as shown in formula (I) as a raw material, mesitylene or a mixture of mesitylene and other organic solvents as a reaction solvent, β-UO3 as a catalyst, and hydrogen peroxide as an oxidant, a catalytic oxidation reaction is carried out to synthesize 1-diphenyldiazene oxide as shown in formula (II); the β-UO3 is prepared by the following method: (1) Preparation of (NH4)2U2O7: Weigh a specific mass of U3O8 prepared from depleted UF6 as raw material, place it in a container, heat and stir while adding concentrated nitric acid to completely dissolve U3O8, then add an appropriate amount of deionized water to form a transparent uranyl salt solution, then add an appropriate amount of precipitant, stir continuously for 5-8 h, separate the solid product, wash and dry to obtain (NH4)2U2O7; (2) Preparation of β-UO3: The precursor (NH4)2U2O7 was ground thoroughly in a mortar, then transferred to a clean porcelain boat, placed in a muffle furnace, and calcined at 500℃ for 5 h at a heating rate of 10℃ / min to obtain β-UO3. Equation (I) Equation (II).
2. The method according to claim 1, characterized in that, The reaction solvent is a mixture of mesitylene and methanol, ethanol, or acetonitrile.
3. The method according to claim 1, characterized in that: The catalyst dosage was 1–20 mg / 0.1 mmol aniline; the reaction temperature was 50–150 °C; the reaction time was 1–20 h; and the hydrogen peroxide dosage was 0.1–1.0 mL.
4. The method according to claim 3, characterized in that: Aniline and β-UO3 were added to the reaction system, hydrogen peroxide was added, and the reaction was carried out at 110℃ for 5 h. After the reaction was completed, the target product was obtained by separation and purification.