CN116196951A - { P-based 4 Mo 6 Crystalline polyacid catalyst for selectively oxidizing aniline under visible light and its application - Google Patents

{ P-based 4 Mo 6 Crystalline polyacid catalyst for selectively oxidizing aniline under visible light and its application Download PDF

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CN116196951A
CN116196951A CN202310023040.7A CN202310023040A CN116196951A CN 116196951 A CN116196951 A CN 116196951A CN 202310023040 A CN202310023040 A CN 202310023040A CN 116196951 A CN116196951 A CN 116196951A
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aniline
crystalline
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polyacid
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王秀丽
张晓艳
刘晓东
徐娜
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Bohai University
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Abstract

{ P-based 4 Mo 6 Crystalline polyacid catalyst for selectively oxidizing aniline under visible light and its application, and the molecular formula of the catalyst is as follows: (Hbiz) 5 {[Co(H 2 O) 3 ][Co(H 2 O) 2 ] 2 }{Co[Mo 6 O 12 (OH) 3 (PO 4 )(HPO 4 ) 3 ][Mo 6 O 12 (OH) 3 (PO 4 ) 2 (HPO 4 ) 2 ]}·3H 2 O selectivityCatalytic oxidation conditions for catalyzing aniline: irradiating under 300W xenon lamp, and using the complex as catalyst at room temperature with mass concentration of 30% H 2 O 2 As an oxidant and Na 2 HSO 3 Under the condition of acetonitrile and acetic acid mixed solvent, the xenon lamp irradiates for 12h. The advantages are that: the preparation method is simple, the raw materials are easy to obtain, and the price is low. The catalyst has higher activity and stability for selectively catalyzing aniline to be oxidized into azobenzene under the drive of visible light.

Description

{ P-based 4 Mo 6 Crystalline polyacid catalyst for selectively oxidizing aniline under visible light and its application
Technical Field
The invention relates to the field of catalyst preparation, in particular to a catalyst based on { P } 4 Mo 6 Crystalline polyacid catalyst for selective oxidation of aniline under visible light conditions and its use.
Background
Azobenzene (AB) is an important small organic molecule that can be used as a dye, indicator and precursor for synthetic natural products. Azobenzene is prepared by catalytic oxidation of precursor aniline, which means that chemically inert aniline molecules must undergo proton-assisted multiple electron transfer processes and complex stepwise oxidation processes, which have high requirements on the catalytic performance of the catalyst.
At present, catalysts for catalyzing aniline oxidation are mainly focused on noble metal nanocomposite materials with abundant surface modification capability and structural stability. Most of these catalysts require high catalyst loadings or strong oxidants and most of the catalytic systems that have been reported require severe reaction conditions to drive the reaction to proceed smoothly, e.g., high pressure and high temperature.
Polyoxometalates (POMs), abbreviated as polyacids, are a variety of functional crystalline metal oxide clusters that can be used as precursors to build coordination polymers to produce functional POMs-based coordination polymers. Coordination polymers are a typical class of crystalline materials with definite structures, wherein certain specific structural components provide potential light response characteristics, and the application of utilizing visible light drive to prepare azobenzene by aniline oxidation has not been developed, so that coordination polymers with active centers and multiple electron donors are expected to replace noble metal catalysts to realize aniline catalytic oxidation to azobenzene.
Disclosure of Invention
The invention aims to provide a { P-based liquid crystal display device 4 Mo 6 Crystalline aniline selective oxidation under visible light conditionsThe polyacid catalyst has higher activity and stability for selectively catalyzing aniline to oxidize into azobenzene under the drive of visible light.
The technical scheme of the invention is as follows:
{ P-based 4 Mo 6 A crystalline polyacid catalyst for the selective oxidation of aniline under visible light conditions, the catalyst having the formula:
(Hbiz) 5 {[Co(H 2 O) 3 ][Co(H 2 O) 2 ] 2 }{Co[Mo 6 O 12 (OH) 3 (PO 4 )(HPO 4 ) 3 ][Mo 6 O 12 (OH) 3 (PO 4 ) 2 (HPO 4 ) 2 ]}·3H 2 O
wherein biz is benzimidazole.
Further, the specific synthesis steps of the polyacid photocatalyst are as follows:
na is mixed with 2 MoO 4 ·2H 2 O, benzimidazole, coCl 2 ·6H 2 O and H 3 PO 4 Adding the mixture into an ethanol water solution according to a molar ratio of 2.06:1:0.85:4.24, mixing, and stirring for 0.5 hours, wherein the volume ratio of ethanol to water in the ethanol water solution is 1:5; then, adjusting pH to 1.9 with NaOH solution with concentration of 1mol/L, sealing in an autoclave lined with 25mL polytetrafluoroethylene, heating in water bath at 160deg.C for 4 days, cooling to room temperature to obtain dark red blocky crystal, washing, and air drying to obtain { P-based crystal 4 Mo 6 Crystalline polyacid catalyst.
Further, the Na is 2 MoO 4 ·2H 2 The molar volume ratio of O to the ethanol aqueous solution is 1.06:3mol/L.
{ P-based 4 Mo 6 The crystalline polyacid catalyst is applied to selectively catalyzing aniline under the condition of visible light, selectively catalyzes aniline to oxidize to azobenzene, shows high catalytic activity, and has excellent conversion rate, selectivity and cycle stability.
{ P-based 4 Mo 6 Crystalline polyacids of }The catalyst is applied to selectively catalyzing aniline under the condition of visible light, and is characterized in that: catalytic oxidation conditions for selective catalytic aniline: irradiating under 300W xenon lamp, and using the complex as catalyst with mass concentration of 30% H at room temperature 2 O 2 As an oxidant and Na 2 HSO 3 Under the condition of a mixed solvent of acetonitrile and acetic acid, irradiating for 12 hours by a xenon lamp;
wherein the mass concentration of the complex is 30% H 2 O 2 、Na 2 HSO 3 Is 5.0X10 mol ratio -3 :2.5:0.1；
The volume ratio of acetonitrile to acetic acid is 7:3;
the molar volume ratio of the complex to the mixed solvent of acetonitrile and acetic acid is 5.0x10 -3 :3mol/L。
Further, when the complex is used as a catalyst, 5.0X10 s per 1mol of aniline are added -3 mol of catalyst.
Further, the room temperature was 25 ℃.
The beneficial effects of the invention are as follows:
(1) The preparation method is simple, the raw materials are easy to obtain, the price is low, no special treatment is needed, and the time and other energy consumption costs are greatly reduced.
(2) Synthesis based on { P } 4 Mo 6 The crystalline polyacid catalyst realizes that aniline derivatives are catalyzed and oxidized to form azo compounds under the condition of visible light for the first time, and no photosensitizer is added in the catalysis process. The conversion rate of the reaction for preparing the azobenzene by photocatalytic oxidation of the aniline can reach 97%, and the selectivity of the azobenzene is 96%.
(3) The { P-based 4 Mo 6 The crystalline polyacid catalyst has the characteristics of high catalytic activity, structural stability and excellent recycling property.
Drawings
FIG. 1 is a powder X-ray diffraction pattern of example 1 of the present invention;
FIG. 2 is an infrared spectrum of example 1 of the present invention;
FIG. 3 is a thermogravimetric curve of example 1 of the present invention;
FIG. 4 is a diagram of the coordination environment of example 1 of the present invention;
FIG. 5 is a one-dimensional block diagram of embodiment 1 of the present invention;
FIG. 6 is a solid state UV-Vis diffuse reflectance spectrum of example 1 of the present invention;
FIG. 7 is a graph of Kubelka-Munk (KM) of example 1 of the present invention;
fig. 8 is a mote-schottky diagram of example 1 of the present invention;
FIG. 9 is a photocurrent response curve of example 1 of the present invention;
FIG. 10 is the cycling stability of example 1 of the present invention;
FIG. 11 is a kinetic study of example 1 of the present invention;
fig. 12 is a PXRD pattern before and after cycling for example 1 of the present invention.
Detailed Description
Example 1 Synthesis (Hbiz) 5 {[Co(H 2 O) 3 ][Co(H 2 O) 2 ] 2 }{Co[Mo 6 O 12 (OH) 3 (PO 4 )(HPO 4 ) 3 ][M o 6 O 12 (OH) 3 (PO 4 ) 2 (HPO 4 ) 2 ]}·3H 2 O
Na is mixed with 2 MoO 4 ·2H 2 O (0.50 g,2.06 mmol), benzimidazole (0.118 g,1 mmol), coCl 2 ·6H 2 O(0.20g,0.85mmol),H 3 PO 4 (8M,0.53mL),1mLC 2 H 5 OH and 5ml H 2 O was stirred for 0.5 hours after mixing, the pH of the mixed solution was adjusted to 1.9 with NaOH (1M), and then the mixed solution was sealed in a 25mL polytetrafluoroethylene-lined autoclave and heated at 160℃for 4 days. Cooling to room temperature to obtain dark red blocky crystal, and drying at room temperature to obtain { P-based crystal 4 Mo 6 Crystalline polyacid catalyst. The yield was 54%.
1. { P) -based Synthesis of example 1 of the present invention 4 Mo 6 Characterization of crystalline polyacid catalyst Complex (hereinafter referred to as Complex)
(1) Characterization of phase purity by powder diffraction
Powder X-ray diffraction (PXRD) patterns were recorded using a D/teX super diffractometer with CuK alpha radiation, operating at 40mA and 40kV voltage. As shown in fig. 1, the powder X-ray diffraction pattern of the complex matches well with the simulated PXRD pattern, indicating that it has high crystallinity and good phase purity.
(2) The infrared spectrum characterizes the phase components
The complexes were tested for IR spectrum on a Varian 640FT-IR Spectrophotometer with a scan range of 400-4000cm -1 . As shown in FIG. 2, { P } is shown in the infrared spectrum of the complex 4 Mo 6 Characteristic vibration of the polyanion: 1010-1064cm -1 Characteristic peaks in the range belong to vibrations of v (P-O), 968cm -1 Characteristic peaks at v (Mo-O) t ) Vibration of 753cm -1 The frequency range of (2) belongs to the vibration of v (Mo-O-Mo). 1531-1620cm -1 The weak absorption bands in the range can be attributed to the vibration of v (C-H) and v (C-N) in the organic ligand, further confirming the components in the complex structure.
(3) Stability of thermogravimetric characterization materials
Using Hitachi TG/DTA7200 Analyzer at N 2 Thermogravimetric analysis was carried out in a flowing atmosphere at a heating rate of 10 ℃/min and a temperature range of 25-800 ℃. As shown in fig. 3, the complex has three weight loss stages in the temperature range of 25 to 800 ℃. The first weight loss stage at 25-230 c may be due to the loss of all water molecules. The second and third weight loss from 230 to 800 ℃ is due to thermal decomposition of the organic ligand and the polyacid.
2. Crystal structure determination
Diffraction data were collected using a Bruker Apex CCD II diffractometer with graphite monochromatic Mo kα radiation (λ= 0.71073) at 293K. Absorption correction is performed using a multi-scan technique. The structure was resolved by a direct method and refined by a full matrix least squares method using the SHELXL program. FIG. 4 shows the coordination environment of the complex synthesized in example 1. Figure 5 shows a one-dimensional block diagram of the complex. The crystallographic data of the complex are shown in table 1:
TABLE 1 crystallographic data
Figure BDA0004041477320000041
Figure BDA0004041477320000051
3. { P) -based Synthesis of example 1 of the present invention 4 Mo 6 Application of crystalline polyacid catalyst complex as polyacid catalyst in catalytic oxidation of aniline
To evaluate the visible light absorption capacity and energy band structure of the complexes, solid state UV-Vis diffuse reflectance spectra, mott-Schottky, and photocurrent response tests were performed. As shown in fig. 6, the complex shows very broad absorption in the 200nm-700nm range, indicating its potential as a photocatalyst. Furthermore, according to the Kubelka-Munk (KM) function (fig. 7), the band gap energy of the complex is about 2.61eV, which means that it has potential for use as a semiconductor photocatalyst.
Electrochemical testing: a standard three-electrode system is adopted, glassy carbon is used as a working electrode, a platinum wire is used as a counter electrode, an Ag/AgCl electrode is used as a reference electrode, and a Mort-Schottky diagram and a photocurrent-time (i-t) curve are recorded on an electrochemical workstation (CHI-760E, shanghai, china). ITO glass (1 cm. Times.1.3 cm) was modified with a sample of catalyst, 2mg of crystals were ground to a powder, mixed with 0.99mL of ethanol and 10. Mu.L of a 0.5% Nafion solution, and sonicated for 60 minutes to form a uniform suspension. Subsequently, 200 μl of the suspension was deposited on ITO glass and dried at room temperature for mott-schottky measurement. The mott-schottky patterns were measured at alternating frequencies of 500Hz, 1000Hz and 1500 Hz. The i-t curve is measured under a 300W xenon lamp light source (C EL-LAX 300).
As shown in FIG. 8, mott-Schotky (MS) tests at various frequencies found that the Conduction Band (CB) potential of the complex was about-0.97V (-0.77V versus NHE) relative to Ag/AgCl. The positive slope of the curve indicates that the complex belongs to the n-type semiconductor material. In addition, the photocurrent response curve (fig. 9) demonstrates the ability of the complex to photo-generate electrons under visible light excitation. In general, the complex synthesized by the embodiment of the invention shows wide visible light absorption and adjustable energy band structure, and therefore, has good application prospect as a photocatalyst.
Synthesis of example 1 (Hbiz) 5 {[Co(H 2 O) 3 ][Co(H 2 O) 2 ] 2 }{Co[Mo 6 O 12 (OH) 3 (PO 4 )(H PO 4 ) 3 ][Mo 6 O 12 (OH) 3 (PO 4 ) 2 (HPO 4 ) 2 ]}·3H 2 The reaction of O as a catalyst for catalyzing and oxidizing aniline under the condition of visible light is tested, and the result shows that the catalyst is based on { P } 4 Mo 6 The polyacid catalyst constructed has excellent catalytic activity to the catalytic system, and can be used as a photocatalyst for catalyzing aniline oxidation.
The process of catalytic oxidation of aniline is as follows:
Figure BDA0004041477320000061
the present invention performs the reaction of photocatalytic oxidation of aniline on a CEL-L870 parallel light reactor (CEL-LAX 300) with a 300W xenon lamp. The temperature of the reaction system was kept at 25 ℃. After the reaction, the aniline oxidation product was identified by GC-MS and quantitatively analyzed by GC internal standard method.
The present invention uses the complex as a catalyst and selects aniline as a reference substrate to optimize the reaction conditions.
First over catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0 mL), naHSO 3 (0.1 equivalent), 30% H 2 O 2 (2.5 eq.) under the conditions of 12h of xenon lamp irradiation, the best solvent was screened. As shown in table 2, the reaction efficiency was more remarkable when a polar solvent was used, and particularly when acetonitrile was used, the reaction conversion rate could reach 80%. When acetic acid was used as the solvent, although the conversion of the reaction was slightly lowered, the selectivity was increased to 83%.
As shown in Table 3, the solvent was the best solvent when the volume ratio of acetonitrile to acetic acid was 7:3, the conversion of the reaction was 84%, and the selectivity of azobenzene could reach 86%.
TABLE 2 influence of solvents on catalytic oxidation of aniline reactions
Figure BDA0004041477320000062
TABLE 3 influence of the ratio of acetonitrile to acetic acid on the catalytic oxidation of aniline
Figure BDA0004041477320000063
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Figure BDA0004041477320000071
In order to further enhance the catalytic reaction effect, inorganic salts are used as additives in the catalytic process. As shown in table 4, when the inorganic salt containing S atom was used, the yield of AB was significantly higher than other additives containing no S atom. When NaHSO is used 3 (0.1 equivalent) the effect of the catalytic oxidation reaction is more remarkable.
TABLE 4 influence of additives on catalytic oxidation of anilines
Figure BDA0004041477320000072
[a]Reaction conditions: catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0. 3.0 ml), naHSO 3 (0.1 eq.) 30% H 2 O 2 (2.5 eq.) xenon lamp, 12h; [ b ]]Reaction conditions: catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0. 3.0 ml), naHSO 3 (0.05 eq.) 30% H 2 O 2 (2.5 eq.) xenon lamp, 12h; [ c ]]Reaction conditions: catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0. 3.0 mL), naHSO 3 (0.15 eq.) 30% H 2 O 2 (2.5 eq.) xenon lamp, 12h; [ d ]]Reaction conditions: aniline (1.0 mmol), solvent (3.0 mL), naHSO 3 (0.1 eq.) 30% H 2 O 2 (2.5 eq.) xenon lamp, 12h.
The invention is combined withThe catalytic activity of each precursor component was evaluated. As shown in Table 5, when CoCl is used 2 、Na 2 MoO 4 And benzimidazole (biz) as catalysts, the conversion and selectivity of the reaction are low. When the three substances are mechanically ground and mixed, the conversion rate can be improved to 72 percent, but the selectivity is only 54 percent, and the catalytic effect is not obviously improved. The results show that the catalyst obtained by simple physical mixing cannot effectively achieve the aim of promoting the aniline coupling reaction. Thus, the crystalline catalyst obtained by the hydrothermal reaction is effective for the catalytic reaction.
TABLE 5 comparison of the oxidation effect of precursor components on aniline
Figure BDA0004041477320000081
[a]Reaction conditions: catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0. 3.0 mL), naHSO 3 (0.1 eq.) 30% H 2 O 2 (2.5 eq.) xenon lamp, 12h.
The invention is characterized in that the catalyst (0.5 mol percent), aniline (1.0 mmol), solvent (3.0 mL) and 30 percent H are fixed 2 O 2 (2.5 eq.) NaHSO 3 (0.1 eq.) under xenon lamp conditions, the effect of time on catalytic oxidation of aniline was investigated. As shown in Table 6, the reaction proceeds to 12h, where the oxidation of aniline to azobenzene is best catalyzed.
TABLE 6 influence of time on aniline oxidation
Figure BDA0004041477320000082
Finally, the influence of environmental factors on the catalytic reaction was investigated. As shown in table 7, when the complex synthesized in example 1 was used as a catalyst, the catalytic effect under the light conditions was superior to that under the absence of light. The catalytic oxidation of aniline not only achieves high conversion under xenon irradiation 12h, but also achieves nearly similar azobenzene yields under real solar irradiation 48h. The selective oxidation of aniline by real solar radiation is very challenging, so the synthesis of the photocatalyst involved in the present invention is of great significance for green-catalysed organic conversion reactions.
TABLE 7 influence of environmental variables on aniline oxidation
Figure BDA0004041477320000091
[a]Reaction conditions: catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0 mL), naHSO 3 (0.1 equivalent); [ b ]]30％ H 2 O 2 (2.5 eq.) xenon lamp, 12h; [ c ]]30％ H 2 O 2 (2.5 eq), sunlight, 48 hours; [ d ]]30％ H 2 O 2 (2.5 eq.) in the dark for 48h.
As shown in Table 8, in the presence of catalyst (0.5 mol%), aniline (1.0 mmol), solvent (3.0 mL), naHSO 3 (0.1 equivalent), 30% H 2 O 2 (2.5 equivalents), the catalytic effect is best under the condition of 12h of xenon lamp irradiation. In the absence of catalyst, the expected product azobenzene and other oxidation products were hardly obtained after 12 hours of reaction, which demonstrates the importance of the catalyst in the catalytic system. When the oxidant becomes O 2 The conversion of aniline is only 8% when N is used 2 Instead of H 2 O 2 In this case, the production of azobenzene was not detected at all. This means that the conversion of aniline and the formation of the target product are closely related to the choice of oxidant, H 2 O 2 Is the best oxidant in the catalytic system.
TABLE 8 deviation of reaction conditions
Figure BDA0004041477320000092
In conclusion, the complex synthesized by the invention can be used as a photocatalyst to effectively catalyze and oxidize aniline to generate azobenzene. In the complex (0.5 mol%) as catalyst, 30% H 2 O 2 (2.5 eq.) as oxidant, na 2 HSO 3 (0.1 equivalent) as an additiveThe optimum catalytic effect was obtained with the addition of MeCN/AcOH (v/v=7:3) as solvent and with the irradiation of a xenon lamp for 12h. The conversion rate of the aniline is up to 97%, and the selectivity of the azobenzene is up to 96%.
The application range of the catalyst for catalytic oxidation of aniline derivatives is evaluated under the optimal reaction condition. As shown in table 9, the catalyst had higher catalytic activity for the oxidation of aniline derivatives. The catalytic effect of the substrates containing electron withdrawing groups (F and Br) is more pronounced than that of the substrates containing electron donating groups (Me, et, iPr, n-Bu and OMe). Furthermore, studies of steric hindrance effects have shown that the yields of para-substituted electron withdrawing group products are significantly higher than ortho-and meta-substituted products. It is noted that when using compounds having larger substituents, more than 65% of azobenzene compounds, such as n-butylaniline or isopropylaniline, may still be obtained.
TABLE 9 catalytic oxidation of aniline derivatives
Figure BDA0004041477320000101
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Figure BDA0004041477320000102
Under the optimal condition, a circulation experiment is carried out on the reaction of catalyzing and oxidizing aniline by the catalyst to evaluate the circularity and stability of the catalyst. As shown in fig. 10, the catalytic activity remained substantially stable after 5 cycles, and the yield of azobenzene was reduced from 93% to 92% due to slight loss of catalyst during recovery. The catalyst was found to have excellent cycle stability. Kinetic studies showed no significant decrease in the initial reaction rate of aniline after 5 cycles, which further indicated that it was somewhat recyclable (fig. 11).
After the catalytic reaction, only trace metal ions are detected in the solution by ICP-MS, and the heterogeneity of the catalyst is proved.
From the infrared spectrogram and the PXRD spectrum (figure 12) of the recovered catalyst, the structure of the catalyst is not obviously changed before and after catalysis, and the structural stability and the integrity of the catalyst in the reaction process are further verified.
The above is only a specific embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (6)

1. { P-based 4 Mo 6 A crystalline polyacid catalyst for the selective oxidation of aniline under visible light conditions, characterized by:
the molecular formula of the catalyst is as follows:
(Hbiz) 5 {[Co(H 2 O) 3 ][Co(H 2 O) 2 ] 2 }{Co[Mo 6 O 12 (OH) 3 (PO 4 )(HPO 4 ) 3 ][Mo 6 O 12 (OH) 3 (PO 4 ) 2 (HPO 4 ) 2 ]}·3H 2 O
wherein biz is benzimidazole.
2. { P-based } -according to claim 1 4 Mo 6 A crystalline polyacid catalyst for the selective oxidation of aniline under visible light conditions, characterized by:
the specific synthesis steps of the polyacid photocatalyst are as follows:
na is mixed with 2 MoO 4 ·2H 2 O, benzimidazole, coCl 2 ·6H 2 O and H 3 PO 4 Adding the mixture into an ethanol water solution according to a molar ratio of 2.06:1:0.85:4.24, mixing, and stirring for 0.5 hours, wherein the volume ratio of ethanol to water in the ethanol water solution is 1:5; then, adjusting pH to 1.9 with NaOH solution with concentration of 1mol/L, sealing in an autoclave lined with 25mL polytetrafluoroethylene, heating in water bath at 160deg.C for 4 days, cooling to room temperature to obtain dark red blocky crystal, washing, and air drying to obtain { P-based crystal 4 Mo 6 Crystalline polyacid catalyst.
3. { P-based } -according to claim 2 4 Mo 6 A crystalline polyacid catalyst for the selective oxidation of aniline under visible light conditions, characterized by: the Na is 2 MoO 4 ·2H 2 The molar volume ratio of O to the ethanol aqueous solution is 1.06:3mol/L.
4. { P-based 4 Mo 6 The application of the crystalline polyacid catalyst used for selectively catalyzing aniline under the condition of visible light is characterized in that: catalytic oxidation conditions for selective catalytic aniline: irradiating under 300W xenon lamp, and using the complex as catalyst at room temperature with mass concentration of 30% H 2 O 2 As an oxidizing agent
Na 2 HSO 3 Under the condition of a mixed solvent of acetonitrile and acetic acid, irradiating for 12 hours by a xenon lamp;
wherein the complex has a mass concentration of 30% H 2 O 2 、Na 2 HSO 3 Is 5.0X10 mol ratio -3 :2.5:0.1；
The volume ratio of acetonitrile to acetic acid is 7:3;
the molar volume ratio of the complex to the mixed solvent of acetonitrile and acetic acid is 5.0x10 -3 :3mol/L。
5. { P-based } -according to claim 4 4 Mo 6 The application of the crystalline polyacid catalyst used for selectively catalyzing aniline under the condition of visible light is characterized in that: when the complex is used as a catalyst, 5.0X10 s of the complex is added per 1mol of aniline -3 mol of catalyst.
6. { P-based } -according to claim 4 4 Mo 6 The application of the crystalline polyacid catalyst used for selectively catalyzing aniline under the condition of visible light is characterized in that: the room temperature was 25 ℃.
CN202310023040.7A 2023-01-06 2023-01-06 { P-based 4 Mo 6 Crystalline polyacid catalyst for selectively oxidizing aniline under visible light and its application Pending CN116196951A (en)

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