Preparation method of depleted uranium-based catalyst UO4. 2H2O and application of depleted uranium-based catalyst UO4. 2H2O in catalytic synthesis of azobenzene or derivatives thereof

Abstract

The wisdom utilization of nuclear energy occupies a core and irreplaceable position in consolidating national defense security and transforming an energy system to greenization. While the nuclear energy technology is vigorously developed, how to properly manage and efficiently recycle depleted uranium (especially 238U, although the depleted uranium does not cause direct radioactive hazards to human bodies) generated in the nuclear energy application process becomes a critical technical challenge faced by the field of environmental protection and sustainable development. Particularly, U3O8 prepared by depleting UF6 is used as a raw material, UO4. 2H2O prepared by a simple dissolution and re-precipitation method is used as a catalyst, and aniline is catalyzed and oxidized to synthesize diphenyl diazene or derivatives thereof. According to the invention, on one hand, a mode of recycling the depleted uranium waste is created, a brand new conversion way is found for the waste which is traditionally considered as a difficult problem, and on the other hand, a bridge from aniline and derivatives thereof to a high value-added chemical, namely diphenyl diazene or derivatives thereof, is skillfully erected. Potential threats of the depleted uranium waste to the environment can be effectively reduced, green transformation and resource utilization of the waste are achieved, meanwhile, the chemical industry can be promoted to proceed towards the more efficient and environment-friendly direction, and economic benefits are remarkably improved for the chemical industry.

Description

Technical Field

[0001] The present invention relates to a new technology for utilizing depleted uranium, in particular to 6 UO was prepared as raw material 4 ·2H 2 The catalyst is used for selective catalytic oxidation of aniline or its derivatives to prepare diphenyldiazene or its derivatives. Technical Background

[0002] In the production process of nuclear fuel, isotope mass separation technology is widely used to enrich natural uranium. This process inevitably produces a large amount of depleted uranium as a by-product. The problem of its treatment can be traced back to the 1940s (see "AngewandteChemie International Edition", 2006, Vol. 46, No. 10, pp. 1562-1563). At present, about 95% of depleted uranium is stored in the form of uranium fluoride (VI), that is, uranium hexafluoride. However, this form has not found a wide range of applications in the commercial field, resulting in a continuous increase in the global backlog of uranium hexafluoride stocks, which has become an environmental and economic challenge that needs to be solved urgently. In view of this situation, how to effectively utilize these dumped uranium hexafluoride stocks has become one of the major issues facing the nuclear power industry. Therefore, from the perspective of economic benefits and environmental sustainable development, actively promoting the effective utilization of depleted uranium rather than simply storing it is undoubtedly a more reasonable and urgent choice.

[0003] Uranium is a unique chemical element. Due to its large radius, the coordination number and unique coordination structure generated by the f orbital's participation in bonding interactions, it is different from transition metal elements and complementary to the chemical reactivity of d-block transition elements. Therefore, uranium-based catalysts show promising catalytic potential. At the same time, the wide range of uranium oxidation states and a large number of thermodynamically stable and metastable phase modifications in uranium-oxygen systems (see Journal of Nuclear Materials, 1995, Vol. 223, No. 3, pp. 231-237) mean that uranium oxide can be effectively used as a component of oxidation process catalysts. In recent years, research on uranium oxides has continued to increase (see Nature, 2012, Vol. 335, No. 6073, pp. 1184-1187), mainly involving UO 2 , U 3 O 8 and UO 3 Uranium oxides such as uranium dioxide. H. Idriss et al. used uranium dioxide to synthesize 4-methyl-1,3-pentadiene through the aldol condensation of acetone dimers (see "Surface Science", 2007, Vol. 601, 5690-5700.). S. V. Hong et al. used UO 2Ethanol is converted into high value-added ethylene (see "Surface Science", 2000, Vol. 444, No. 1, 187-198.).

[0004] Diphenyldiazene or its derivatives are a class of important and high-value fine chemicals, which are widely used in organic dyes, chemical indicators, food preservatives, additives, free radical reaction initiators, polymers and medicines. In addition, it can also be used as a precursor for the synthesis of complex natural products. It has broad market prospects and demands.

[0005] In view of the unique characteristics of uranium oxides, such as the wide range of uranium oxidation states and a large number of thermodynamically stable and metastable phases in the uranium-oxygen system, their catalytic oxidation ability is significantly enhanced. In addition, the current nuclear industry is facing the major challenge of depleted uranium storage and application that needs to be overcome. Therefore, it is considered to design a uranium-based catalyst prepared from depleted uranium waste as raw material. This catalyst is designed to catalyze the oxidation reaction of aniline and its derivatives. Through its unique catalytic performance, the method of promoting the synthesis of high-value diphenyldiazene or its derivatives has not been reported so far.

[0006] In summary, we have developed a new uranium-based heterogeneous catalyst UO 4 ·2H 2 O, and for the first time applied it to the field of thermal catalysis to achieve efficient synthesis of fine chemicals. The catalyst preparation method is simple, and it is based on depleted UF 6 U 3 O 8 As raw material, it can be prepared by solvent-reprecipitation method. What is more worth mentioning is that UO 4 ·2H 2 The method of directly catalyzing aniline to synthesize diphenyldiazene or its derivatives by O has not been reported so far. Summary of the invention

[0007] The present invention finds that depleted UF 6 U 3 O 8 As raw material, UO 4 ·2H 2 The catalyst O can catalytically oxidize aniline or its derivatives to form diphenyldiazene or its derivatives. Therefore, the present invention not only provides a new method for utilizing depleted uranium, but also proposes a low-cost, green and efficient method for preparing diphenyldiazene or its derivatives. The method is simple, low-cost, and highly safe, and is more in line with the concept of green and friendly chemistry. Specifically, it includes the following contents:

[0008] In a first aspect, the present invention provides a method for preparing a depleted UF 6 U 3 O8 As raw material, UO was prepared by simple dissolution and reprecipitation. 4 ·2H 2 O Catalyst method.

[0009] Preferably, the catalyst preparation method comprises the following steps:

[0010] (1) UO 4 ·2H 2 Preparation of O: Weigh a specific mass to deplete UF 6 U 3 O 8 , put it in a container, heat and stir, add appropriate amount of concentrated nitric acid or concentrated hydrochloric acid, 3 O 8 After complete dissolution, add an appropriate amount of deionized water to form a transparent uranyl salt solution, then add an appropriate amount of hydrogen peroxide, continue stirring for several hours, separate the solid product, wash and dry it to obtain UO 4 ·2H 2 O. Its XRD crystal structure is shown in the attached Figure 1 The transmission electron microscope image is shown in the attached Figure 2 The scanning electron microscope image is shown in the attached Figure 3 The nitrogen isotherm adsorption curve is shown in the attached figure. Figure 4 shown.

[0011] Preferably, the structural formula of the aniline or its derivative is as shown in the following formula (I), and the structural formula of the diphenyldiazene or its derivative is as shown in the following formula (II)

[0012]

[0013] Among them, R 1 -R 5 Each of them is selected from hydrogen, halogen, hydroxyl, sulfonic acid, nitro, substituted or unsubstituted straight or branched alkyl, alkoxy, carbonyl, alkenyl, alkynyl, substituted or unsubstituted aryl, acylamino, and cyano, but is not limited to the above substituents.

[0014] Preferably, the R 1 -R 5 They are respectively selected from hydrogen, methyl, chlorine, bromine and methoxy.

[0015] Preferably, the aniline or its derivatives include: aniline, o-methylaniline, m-methylaniline, p-methylaniline, p-chloroaniline, p-bromoaniline and p-methoxyaniline.

[0016] Preferably, the catalyst is UO 4 ·2H 2 O.

[0017] Preferably, the ratio of the catalyst to aniline or its derivatives is 1-50 mg:1 mol.

[0018] Preferably, the ratio of the catalyst to aniline or its derivatives is 10-40 mg:1 mol.

[0019] Preferably, the ratio of the catalyst to aniline or its derivatives is 30 mg:1 mol.

[0020] Preferably, the oxidant is tert-butyl hydroperoxide.

[0021] Preferably, the molar ratio of the tert-butyl hydroperoxide to aniline or its derivatives is 1-14:1.

[0022] Preferably, the molar ratio of the tert-butyl hydroperoxide to aniline or its derivatives is 2-8:1.

[0023] Preferably, the molar ratio of tert-butyl hydroperoxide to aniline or its derivatives is 7:1.

[0024] Preferably, the organic solvent is acetic acid.

[0025] Preferably, the mass ratio of the reaction solvent to aniline or its derivatives is 1-67:1.

[0026] Preferably, the mass ratio of the reaction solvent to aniline or its derivatives is 10-50:1.

[0027] Preferably, the mass ratio of the reaction solvent to aniline or its derivatives is 33:1.

[0028] Preferably, the method comprises: reacting aniline or its derivatives, UO 4 ·2H 2 O. Add tert-butyl hydroperoxide to the reaction solvent, react at 30-120° C. for 1-16 hours; filter, distill and recrystallize to obtain diphenyldiazene or its derivatives. Preferably, the reaction temperature is 60-100° C.

[0029] Preferably, the reaction temperature is 30-120°C.

[0030] Preferably, the reaction temperature is 60-100°C.

[0031] Preferably, the reaction temperature is 80°C.

[0032] Preferably, the reaction time is 1-16h.

[0033] Preferably, the reaction time is 2-14 hours.

[0034] Preferably, the reaction time is 12 h.

[0035] Compared with the prior art, the method for preparing diphenyldiazene or its derivatives by catalytic oxidation of aniline or its derivatives of the present invention has the following advantages:

[0036] (1) The present invention uses depleted uranium waste as raw material to prepare the catalyst, which effectively solves the problem of safe disposal and reuse of depleted uranium in my country's nuclear energy utilization;

[0037] (2) Aniline or its derivatives used in the present invention are basic raw materials commonly used in industry and are cheap and readily available.

[0038] (3) The present invention uses cheap and readily available tert-butyl hydroperoxide as an oxidant, and the reaction temperature is moderate, which is different from the traditional method using peracetic acid, Pb(OAc) 4 、Hg(OAc) 2 、BaMnO 4 Compared with other oxidants, it greatly reduces the cost of oxidants and solves the problem of toxic substance emissions generated by the use of oxidants.

[0039] (4) The method of the present invention can catalytically oxidize aniline or its derivatives to the corresponding diphenyldiazene or its derivatives with good specificity and a high yield of the target product.

[0040] The present invention will be further described in detail with reference to specific embodiments, but the protection scope of the present invention is not limited thereto. The raw materials used in the following embodiments are all commercially available unless otherwise specified. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The prepared catalyst UO 4 ·2H 2 X-ray diffraction crystal structure of O;

[0042] Figure 2 The prepared catalyst UO 4 ·2H 2 Transmission electron micrograph of O;

[0043] Figure 3 The prepared catalyst UO 4 ·2H 2 Scanning electron micrograph of O;

[0044] Figure 4 Prepared UO 4 ·2H 2 Nitrogen isotherm adsorption curve of O catalyst;

[0045] Figure 5 Mass spectrum of diphenyldiazene synthesized by the method described in Example 1;

[0046] Figure 6 Mass spectrum of diphenyldiazene synthesized by the method described in Example 2;

[0047] Figure 7 Mass spectrum of the product diphenyldiazene synthesized by the method described in Example 3;

[0048] Figure 8 Mass spectrum of diphenyldiazene synthesized by the method described in Example 4;

[0049] Fig. 9 Mass spectrum of diphenyldiazene synthesized by the method described in Example 5;

[0050] Fig.10 Mass spectrum of diphenyldiazene, the product synthesized by the method described in Example 6;

[0051] Fig.11 Mass spectrum of the product 2,2'-dimethyl-diphenyldiazene synthesized by the method described in Example 7;

[0052] Fig.12 Mass spectrum of the product 3,3'-dimethyldiphenyldiazene synthesized by the method described in Example 7;

[0053] Fig.13 Mass spectrum of the product 4,4'-dimethyl-diphenyldiazene synthesized by the method described in Example 7;

[0054] Fig.14 Mass spectrum of the product 4,4'-dichloro-diphenyldiazene synthesized by the method described in Example 7;

[0055] Fig.15 Mass spectrum of the product 4,4'-dibromo-diphenyldiazene synthesized by the method described in Example 7;

[0056] Fig.16 Mass spectrum of the product 4,4'-dimethoxy-diphenyldiazene synthesized by the method described in Example 7; DETAILED DESCRIPTION

[0057] The present invention is further described in detail below in conjunction with specific examples, but the protection scope of the present invention is not limited thereto. The raw materials used in the following examples are all commercially available unless otherwise specified.

[0058] Example 1 Synthesis of diphenyldiazene using different reaction solvents

[0059] 1. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.66 g of formic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0060] 2. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0061] 3. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 2.7 g of n-butyric acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0062] 4. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline, 3.66 g of formic acid and acetic acid solvent (mass ratio of 1:1) were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0063] 5. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline, 3.66 g of formic acid and n-butyric acid solvent (mass ratio 1:1) were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0064] 6. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline, 3.15 g of acetic acid and n-butyric acid solvent (mass ratio 1:1) were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80°C while stirring, and the reaction was carried out for 12 hours, and then the product diphenyldiazene was obtained by filtration, distillation and recrystallization. .

[0065] The product yield of diphenyldiazene obtained by the preparation method described in 1-6 above was calculated, and the results are shown in Table 1 below:

[0066] Table 1 Process parameters of the preparation method described in Example 1 and the yield of the product diphenyldiazene

[0067]

[0068] The mass spectrum of the product synthesized by the above reaction is as follows 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 of the product is shown in Formula 1. The above results show that when an organic solvent (formic acid, acetic acid, n-butyric acid, or a combination thereof, etc.) is used as the reaction solvent, tert-butyl hydroperoxide is used as the oxidant, and UO 4 ·2H 2 O is a catalyst, which can catalyze aniline to synthesize diphenyldiazene; and with acetic acid as the reaction solvent, the yield of the obtained diphenyldiazene can reach up to 92%.

[0069]

[0070] Example 2 Synthesis of diphenyldiazene with different amounts of reaction solvent

[0071] 1. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 1.05 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0072] 2. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 2.1 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product diphenyldiazene.

[0073] 3. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0074] 4. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 4.2 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product diphenyldiazene.

[0075] 5. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 5.25 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0076] 6. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 6.3 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product diphenyldiazene.

[0077] The product yield of diphenyldiazene obtained by the preparation method described in 1-6 above was calculated, and the results are shown in Table 2 below:

[0078] Table 2 Process parameters of the preparation method described in Example 2 and the yield of the product diphenyldiazene

[0079]

[0080] The mass spectrum of the main product obtained from the above reaction is as follows 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 of the product is shown in Formula 1. The above results show that when acetic acid is used as the reaction solvent (the mass ratio of acetic acid to aniline is 1-67:1), tert-butyl hydroperoxide is used as the oxidant, and UO 4 ·2H 2 O is a catalyst, which can catalyze aniline to synthesize diphenyldiazene; meanwhile, when the mass ratio of mesitylene to aniline is 21-45:1, the yield of diphenyldiazene obtained by the reaction is above 90%.

[0081]

[0082] Example 3 Synthesis of diphenyldiazene at different reaction temperatures

[0083] 1. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 30° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0084] 2. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 40° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0085] 3. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 50° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0086] 4. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 60° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0087] 5. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 70° C. with stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0088] 6. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0089] 7. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 90° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0090] 8. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 100 ° C. The reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0091] 9. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 110° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazepine.

[0092] 10. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 120° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazepine.

[0093] The product yield of diphenyldiazene obtained by the preparation method described in 1-10 above was calculated, and the results are shown in Table 3 below:

[0094] Table 3 Process parameters of the preparation method described in Example 3 and the yield of the product diphenyldiazene

[0095]

[0096] The mass spectrum of the main product obtained from the above reaction is as follows Figure 7 As shown (the mass spectra of the above 10 main products are the same, so only one mass spectrum is provided), the structural formula of the product is shown in Formula 1. The above results show that when acetic acid is used as the reaction solvent, the reaction temperature is 30-120°C, tert-butyl hydroperoxide is used as the oxidant, and UO 4 ·2H 2 O is a catalyst, which can catalyze aniline to synthesize diphenyldiazene; when the reaction temperature is 50-90°C, the yield of diphenyldiazene obtained by the reaction is above 80%; and when the reaction temperature is 70-80°C, the yield of diphenyldiazene obtained by the reaction is as high as above 90%.

[0097]

[0098] Example 4 Synthesis of diphenyldiazene with different reaction times

[0099] 1. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 1 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0100] 2. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 2 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0101] 3. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 4 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0102] 4. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 6 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0103] 5. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 8 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0104] 6. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring. The reaction was carried out for 10 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0105] 7. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0106] 8. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 14 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0107] 9. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 16 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0108] The product yield of diphenyldiazene obtained by the preparation methods 1-9 above was calculated, and the results are shown in Table 4 below:

[0109] Table 4 Process parameters of the preparation method described in Example 4 and the yield of the product diphenyldiazene

[0110]

[0111] The mass spectrum of the main product obtained from the above reaction is as follows Figure 8As shown (the mass spectra of the main products of the above 9 reactions are the same, so only one mass spectrum is provided), the structural formula of the product is shown in Formula 1. The above results show that when acetic acid is used as the reaction solvent and the reaction time is 1-16h, tert-butyl hydroperoxide is used as the oxidant and UO 4 ·2H 2 O is a catalyst, which can catalyze aniline to synthesize diphenyldiazene; when the reaction time is 10-16 hours, the yield of diphenyldiazene obtained by the reaction is above 80%; and when the reaction time is 12-16 hours, the yield of diphenyldiazene obtained by the reaction is higher than 92%.

[0112]

[0113] Example 5 Synthesis of diphenyldiazene with different amounts of tert-butyl hydroperoxide added

[0114] 1. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 1 mmol of tert-butyl hydroperoxide (i.e., 0.137 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0115] 2. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 2 mmol of tert-butyl hydroperoxide (i.e., 0.274 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0116] 3. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 3 mmol of tert-butyl hydroperoxide (i.e., 0.411 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0117] 4. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 4 mmol of tert-butyl hydroperoxide (i.e., 0.584 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0118] 5. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0119] 6. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 6 mmol of tert-butyl hydroperoxide (i.e., 0.822 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0120] 7. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 7 mmol of tert-butyl hydroperoxide (i.e., 0.959 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0121] 8. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 8 mmol of tert-butyl hydroperoxide (i.e., 1.096 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0122] 9. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 9 mmol of tert-butyl hydroperoxide (i.e., 1.233 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0123] 10. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 10.0 mmol of tert-butyl hydroperoxide (i.e., 1.370 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0124] The product yield of diphenyldiazene obtained by the preparation method described in 1-10 above was calculated, and the results are shown in Table 5 below:

[0125] Table 5 Process parameters of the preparation method described in Example 5 and the yield of the product diphenyldiazene

[0126]

[0127] The mass spectrum of the main product obtained from the above reaction is as follows Fig. 9 As shown (the mass spectra of the main products of the above 10 reactions are the same, so only one mass spectrum is provided), the structural formula of the product is shown in Formula 1. The above results show that when the molar ratio of the oxidant tert-butyl hydroperoxide to aniline is 1-14:1, acetic acid is used as the reaction solvent, and UO 4 ·2H 2 O is a catalyst, and aniline can be synthesized into diphenyldiazene; when the molar ratio of the oxidant tert-butyl hydroperoxide to aniline is 1-6:1, the product yield is higher than 80%; and when the molar ratio of the oxidant tert-butyl hydroperoxide to aniline is 6-7:1, the product yield is as high as more than 92%.

[0128]

[0129] Example 6 Synthesis of diphenyldiazene with different catalyst addition amounts

[0130] 1. UO 4 ·2H 21.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0131] 2. UO 4 ·2H 2 5.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0132] 3. UO 4 ·2H 2 10.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0133] 4. UO 4 ·2H 2 15.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0134] 5. UO 4 ·2H 2 20.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0135] 6. UO 4 ·2H 225 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0136] 7. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0137] 8. UO 4 ·2H 2 35.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0138] 9. UO 4 ·2H 2 40.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0139] 10. UO 4 ·2H 2 45.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of a tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 h, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0140] 11. UO 4 ·2H 250.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.093 g of aniline and 3.15 g of acetic acid were added, and 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80° C. while stirring, and the reaction was carried out for 12 hours, and then filtered, distilled and recrystallized to obtain the product diphenyldiazene.

[0141] The product yield of diphenyldiazene obtained by the preparation method described in 1-11 above was calculated, and the results are shown in Table 6 below:

[0142] Table 6 Process parameters of the preparation method described in Example 6 and the yield of the product diphenyldiazene

[0143]

[0144]

[0145] The mass spectrum of the main product obtained from the above reaction is as follows Fig.10 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 of the product is shown in Formula 1. The above results show that acetic acid is used as the reaction solvent, tert-butyl hydroperoxide is used as the oxidant, and UO 4 ·2H 2 O is a catalyst, and when the ratio of the catalyst to aniline or its derivatives is 1-50 mg:1 mol, aniline can be catalyzed to synthesize diphenyldiazene; and when the ratio of the catalyst to aniline or its derivatives is 25-50 mg:1 mol, the yield of diphenyldiazene obtained by the reaction is higher than 80%; and when the ratio of the catalyst to aniline or its derivatives is 30-40 mg:1 mol, the yield of diphenyldiazene obtained by the reaction can reach more than 92%.

[0146]

[0147] Example 7 Synthesis of diphenyldiazene derivatives using different aniline derivatives

[0148] 1. UO 4 ·2H 2 30.0 mg of O catalyst was added to a 25 mL reaction tube, and then 0.107 g of o-methylaniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of 70% tert-butyl hydroperoxide aqueous solution) was added dropwise at 80°C while stirring. The reaction was continued for 12 hours, and then filtered, distilled, and recrystallized to obtain the product 2,2'-dimethyl-diphenyldiazene. The mass spectrum of the product is shown in FIG. Fig.11 As shown, the structural formula is shown in Formula 2.

[0149]

[0150] 2. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.107 g of m-methylaniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80°C while stirring. The reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product 3,3'-dimethyl-diphenyldiazene. The mass spectrum of the product is shown in FIG. Fig.12 As shown, the structural formula is shown in Formula 3.

[0151]

[0152] 3. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.107 g of p-methylaniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80°C while stirring. The reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product 4,4'-dimethyl-diphenyldiazene. The mass spectrum of the product is shown in FIG. Fig.13 As shown, the structural formula is shown in Formula 4.

[0153]

[0154] 4. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.127 g of p-chloroaniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80°C while stirring. The reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product 4,4'-dichloro-diphenyldiazene. The mass spectrum of the product is shown in FIG. Fig.14 As shown, the structural formula is shown in Formula 5.

[0155]

[0156]

[0157] 5. UO 4 ·2H 230.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.172 g of p-bromoaniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80°C while stirring. The reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product 4,4'-dibromo-diphenyldiazene. The mass spectrum of the product is shown in FIG. Fig.15 As shown, the structural formula is shown in Formula 6.

[0158]

[0159] 6. UO 4 ·2H 2 30.0 mg of O catalyst was added to a reaction tube with a volume of 25 mL, and then 0.123 g of p-methoxyaniline and 3.15 g of acetic acid were added. 5 mmol of tert-butyl hydroperoxide (i.e., 0.685 mL of tert-butyl hydroperoxide aqueous solution with a mass content of 70%) was added dropwise at 80°C while stirring. The reaction was carried out for 12 hours, and then filtered, distilled, and recrystallized to obtain the product 4,4'-dimethoxy-diphenyldiazene. The mass spectrum of the product is shown in FIG. Fig.16 As shown, the structural formula is shown in Formula 7.

[0160]

[0161] The product yield of the diphenyldiazene derivative obtained by the preparation method described in 1-6 above was calculated, and the results are shown in Table 7 below:

[0162] Table 7 Process parameters and product yields of the preparation method described in Example 7

[0163]

[0164]

[0165] The mass spectra of the main products in the above reactions 1-6 are as follows: Figure 11-16 The above results show that acetic acid is used as the reaction solvent, tert-butyl hydroperoxide is used as the oxidant, and UO 4 ·2H 2O is a catalyst, which can catalyze the synthesis of 2,2'-dimethyl-diphenyldiazene from o-methylaniline with a yield of 85%; catalyze the synthesis of 3,3'-dimethyl-diphenyldiazene from m-methylaniline with a yield of 83%; catalyze the synthesis of 4,4'-dimethyl-diphenyldiazene from p-methylaniline with a yield of 94%; catalyze the synthesis of 4,4'-dichloro-diphenyldiazene from p-chloroaniline with a yield of 97%; catalyze the synthesis of 4,4'-dibromo-diphenyldiazene from p-bromoaniline with a yield of 97%; and catalyze the synthesis of 4,4'-dimethoxy-diphenyldiazene from p-methoxyaniline with a yield of 94%. Therefore, the method of the present invention can catalyze the synthesis of diphenyldiazene or its derivatives from aniline or its derivatives, and the yield of the target product obtained is high.

[0166] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. Preparation method of depleted uranium-based UO4·2H2O and its application in catalytic synthesis of diphenyldiazene or its derivatives.

2. As claimed in claim 1, a method for preparing a UO4·2H2O heterogeneous catalyst, characterized in that: U3O8 made from depleted UF6 is used as the starting material, concentrated acid is used as the solvent, a specific precipitant is used as the auxiliary, and deionized water is used as the diluent. The specific operation steps are as follows: Preparation of UO4·2H2O: Weigh a specific mass of U3O8 prepared with depleted UF6 as raw material, place it in a container, add an appropriate amount of concentrated acid while heating and stirring, so that U3O8 is completely dissolved, then add an appropriate amount of deionized water to form a transparent uranyl salt solution, and then add an appropriate amount of oxidant. After continuous stirring for several hours, separate the solid product, wash and dry it to obtain UO4·2H2O.

3. A method for preparing UO4·2H2O according to claims 1 and 2, characterized in that: The concentrated acid described in claim 2 is concentrated nitric acid with a mass fraction greater than 65% or concentrated hydrochloric acid with a mass fraction greater than 37%, the oxidant is hydrogen peroxide with a mass fraction greater than 25%, the uranyl salt is uranyl nitrate or uranyl chloride, and the stirring time is 2-25h.

4. A method for preparing UO4·2H2O according to claims 1 and 2, characterized in that: The drying temperature described in claim 2 is 60-240° C. and the drying time is 2-8 hours.

5. The use of the catalytic synthesis of diphenyldiazene or its derivatives as claimed in claim 1, characterized in that: The structural formula of the diphenyldiazene or its derivatives is shown in the following formula (II). The raw material for synthesizing diphenyldiazene or its derivatives is aniline or its derivatives, and its structural formula is shown in the following formula (I): Among them, R1-R5 are independently selected from any one of hydrogen, halogen, hydroxyl, sulfonic acid, nitro, substituted or unsubstituted straight or branched alkyl, alkoxy, carbonyl, alkenyl, alkynyl, substituted or unsubstituted aryl, acylamino, and cyano.

6. A method for preparing diphenyldiazene or a derivative thereof as claimed in claims 1 and 5, comprising: A method for preparing diphenyldiazene or its derivatives, comprising: using aniline or its derivatives as a raw material, acetic acid or a mixed solvent of acetic acid and other organic solvents as a reaction solvent, UO4·2H2O as a catalyst, and tert-butyl hydroperoxide as an oxidant, to catalyze and oxidize to synthesize diphenyldiazene or its derivatives as a formula (II), wherein the organic solvent comprises formic acid, acetic acid, and n-butyric acid; Among them, R1-R5 are independently selected from any one of hydrogen, halogen, hydroxyl, sulfonic acid, nitro, substituted or unsubstituted straight or branched alkyl, alkoxy, carbonyl, alkenyl, alkynyl, substituted or unsubstituted aryl, acylamino, and cyano.

7. The synthesis method according to claims 1, 5 and 6, characterized in that The dosage ratio of the catalyst to aniline or its derivative is 1-50 mg:1 mmol; the mass ratio of the reaction solvent to aniline or its derivative is 1-67:1; the volume of the tert-butyl hydroperoxide is 0.1-1.0 mL; the reaction temperature is 30-120° C.; and the reaction time is 1-16 h.

8. The synthesis method according to claims 5-7, characterized in that The R1-R5 are selected from hydrogen, methyl and chlorine respectively. The aniline or its derivatives include: aniline, o-methylaniline, p-methylaniline, p-chloroaniline, n-chloroaniline and m-chloroaniline.

9. The synthesis method according to any one of claims 5 to 8, characterized in that: Aniline or its derivatives, UO4·2H2O (the amount ratio of UO4·2H2O to aniline or its derivatives is 30 mg:1 mmol), and TBHP (the molar ratio of TBHP to aniline or its derivatives is 14:1) are added to acetic acid (the mass ratio of TBHP to aniline or its derivatives is 33:1), and reacted at 80° C. for 12 hours; and diphenyldiazene or its derivatives are obtained by filtration, distillation, and recrystallization.

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