CdS / Bi / Ti3C2T X Photocatalyst, preparation method and application thereof

Abstract

The application discloses a kind of CdS / Bi / Ti3C2T X Photocatalyst and its preparation method and application.The CdS / Bi / Ti3C2T X Photocatalyst is ternary composite material, by CdS nanorod, Bi nanosheet and two-dimensional nanosheet Ti3C2T X Composition;Wherein Bi nanosheet is on the surface of CdS nanorod, and is formed by ion exchange in-situ reduction, and CdS nanorod is uniformly distributed in two-dimensional nanosheet Ti3C2T X Above.The CdS / Bi / Ti3C2T X Photocatalyst prepared by the application can be used to catalyze oxidation hydroxylation of aryl boronic acid and oxidation coupling of benzyl amine, can directly use oxygen in air as oxidant, has the characteristics of mild condition, high yield, low cost, easy operation, environmental friendliness, easy separation and recovery, can be reused, etc., and has industrialization prospect.

Description

Technical Field

[0001] This invention relates to the field of material preparation and catalytic synthesis technology, specifically to a CdS / Bi / Ti3C2T X Photocatalysts, their preparation methods, and applications. Background Technology

[0002] Phenolic compounds are important structural segments in natural products and drug molecules. Industrial synthesis methods mainly include oxidation or hydrolysis of halogenated aromatic hydrocarbons, which require stringent conditions and are costly. Therefore, the synthesis of phenols via the hydroxylation of arylboronic acids has attracted widespread attention. Traditional methods for achieving hydroxylation of boronic acids primarily utilize stoichiometric amounts of strong oxidants, such as hydrogen peroxide, ozone, high-iodine reagents, and potassium bisulfate. However, these oxidants, besides requiring large quantities, also suffer from instability and explosiveness, which are not conducive to the development of sustainable green chemistry. In recent years, the photocatalytic hydroxylation of aromatic boronic acids to prepare phenol has garnered significant attention. Common photocatalysts mainly include organic dyes and transition metal complexes. However, these photocatalysts suffer from drawbacks such as difficulty in recycling, easy decomposition, and high cost. Therefore, the development of efficient, stable, and easily separable heterogeneous photocatalysts based on semiconductors remains an urgent need.

[0003] There have been some reports on the oxidative hydroxylation of boric acid catalyzed by heterogeneous photocatalysts, both domestically and internationally. For example, in the literature (Angewandte Chemie International Edition 2022, 61, 202114059), a two-dimensional COF material was used as a photocatalyst to achieve the oxidative hydroxylation of boric acid, but an oxygen atmosphere is required for the reaction, which limits its potential for industrial application. In the literature (Journal of Catalysis 2022, 414, 64-75), potassium-doped carbon nitride was used as a photocatalyst to achieve the oxidative hydroxylation of boric acid under air conditions, but 0.1 mmol of substrate required 10 mg of catalyst and 2 mL of solvent, which places high demands on the amount of catalyst used, and the yield was not ideal, resulting in a waste of resources.

[0004] Compared to the ternary composite Bi@MXene / CdS synthesized by the method reported in CN 111111735, which first introduces bismuth into MXene and then introduces a semiconductor, the ternary composite photocatalyst CdS / Bi / Ti3C2T synthesized in this invention... X It has better photocatalytic activity. Summary of the Invention

[0005] This invention addresses the shortcomings of existing technologies by providing a CdS / Bi / Ti3C2T XA photocatalyst, its preparation method, and its application were described. This photocatalyst was used for the oxidative hydroxylation reaction of arylboronic acids, achieving high yields easily with low catalyst amounts under air and visible light conditions. The catalyst exhibits high photocatalytic activity, low cost, ease of preparation, environmental friendliness, and reusability, demonstrating promising industrial application potential. The synthesized ternary composite photocatalyst CdS / Bi / Ti3C2T... X It can be used not only for the oxidative hydroxylation of arylboronic acids, but also for other oxidation reactions, such as the oxidative coupling reaction of benzylamines.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A CdS / Bi / Ti3C2T X Photocatalyst, the CdS / Bi / Ti3C2T X The photocatalyst is a ternary composite material consisting of CdS nanorods, Bi nanosheets, and two-dimensional nanosheets Ti3C2T. X Composition: Bi nanosheets are formed on the surface of CdS nanorods through in-situ reduction via ion exchange, and the CdS nanorods are uniformly distributed on the two-dimensional nanosheets Ti3C2T. X superior.

[0008] The CdS / Bi / Ti3C2T X Photocatalysts can be used for the oxidative coupling of benzylamines and the hydroxylation of arylboronic acids, and can maintain good photocatalytic activity while being recycled.

[0009] The above-mentioned CdS / Bi / Ti3C2T X The preparation method of the photocatalyst includes the following steps:

[0010] (1) After removing the Al layer of Ti3AlC2 with LiF and HCl (to obtain Ti3C2), the Ti3AlC2 was ultrasonically treated in water under inert gas protection. The supernatant was collected by centrifugation and dried to obtain a single layer of two-dimensional nanosheets Ti3C2T. X ;

[0011] (2)Cd 2+ After stirring, CdS nanomaterials were formed by dispersing thiourea and ethylenediamine and then undergoing a solvothermal reaction. After the reaction was completed, the nanomaterials were washed and dried to obtain CdS nanomaterials.

[0012] (3) The CdS nanomaterials prepared in step (2) and Bi 3+ The source was added to ethylene glycol and heated to react. After the reaction was completed, the mixture was washed and dried. The resulting solid was redissolved in a solution of NaBH4 and stirred to react. After the reaction was completed, the mixture was washed and dried to obtain the CdS / Bi composite material.

[0013] (4) The monolayer two-dimensional nanosheets Ti3C2T prepared in step (1) X The CdS / Bi composite material prepared in step (3) was added to water, stirred, and reacted. After the reaction was completed, the mixture was washed and dried to obtain CdS / Bi / Ti3C2T. X Photocatalyst.

[0014] Preferably, the method for removing the Al layer from Ti3AlC2 using LiF and HCl in step (1) is as follows: LiF powder is added to concentrated hydrochloric acid and stirred for 20-70 min in a constant temperature water bath at 20-50℃; then Ti3AlC2 powder is added to the solution in portions, and the reaction continues for 20-72 h at a stirring speed of 380-800 r / min. After the reaction is completed, the reaction solution is centrifuged, the black precipitate is collected, and washed 5-10 times with ultrapure water; the volume-to-mass ratio of concentrated hydrochloric acid to Ti3AlC2 powder is 2-20 mL: 1 g; the concentration of concentrated hydrochloric acid is 36%-38%; and the mass ratio of LiF to Ti3AlC2 is 1-3: 0.5-3.5.

[0015] More preferably, the stirring temperature in the constant temperature water bath is 30-40℃, and the time is 30-60 min; the reaction time is 20-48 h; the stirring speed is 380-600 r / min; the number of times the ultrapure water is washed is 5-7 times; the volume-to-mass ratio of concentrated hydrochloric acid to Ti3AlC2 powder is 5-20 mL: 1 g; and the mass ratio of LiF to Ti3AlC2 is 1-2: 0.5-3.5.

[0016] Preferably, the ultrasonic treatment time in step (1) is 20-100 min; the centrifugation speed is 2800-5000 rpm;

[0017] More preferably, the centrifugation speed in step (1) is 2800-4000 rpm; the ultrasonic treatment time is 40-100 min;

[0018] Preferably, the water in step (1) is ultrapure water; the inert gas is argon. The volume ratio of the water to the mass ratio of Ti3C2 is 100-300 mL: 1 g.

[0019] Preferably, the Cd in step (2) 2+ The mass ratio of the source to thiourea is 550-800:550-800;

[0020] Further preferably, the Cd in step (2) 2+ The mass ratio of the source to thiourea is 550-770:550-780;

[0021] Preferably, the ethylenediamine and Cd in step (2)2+ The volume-to-mass ratio of the source is 10-30 mL: 0.5-1 g;

[0022] Further preferably, the ethylenediamine and Cd in step (2) 2+ The volume-to-mass ratio of the source is 15-30 mL: 0.5-1 g;

[0023] Preferably, the stirring time in step (2) is 10-60 min;

[0024] More preferably, the stirring time in step (2) is 10-40 min;

[0025] Preferably, the temperature of the solvothermal reaction in step (2) is 100-200℃, and the time of the solvothermal reaction is 12-36h;

[0026] More preferably, the temperature of the solvothermal reaction in step (2) is 120-200℃ and the reaction time is 15-30h.

[0027] Preferably, the Cd in step (2) 2+ The source is Cd(NO3)2·4H2O.

[0028] Preferably, the Bi in step (3) 3+ The mass ratio of the source material to CdS nanomaterials is 200-350:200-350;

[0029] More preferably, the Bi described in step (3) 3+ The mass ratio of source material to CdS nanomaterials is 200-320:200-300;

[0030] Preferably, the volume-to-mass ratio of ethylene glycol to CdS nanomaterials in step (3) is 5-40 mL: 0.1-0.5 g;

[0031] More preferably, the volume-to-mass ratio of ethylene glycol to CdS nanomaterials in step (3) is 5-30 mL: 0.1-0.5 g;

[0032] Preferably, the heating reaction temperature in step (3) is 30-100℃; the heating reaction time is 1-5h.

[0033] More preferably, the temperature of the heating reaction in step (3) is 40-100℃; and the heating reaction time is 1-4h.

[0034] Preferably, the NaBH4 solution in step (3) is a 0.1-5M water or ethanol solution;

[0035] More preferably, the NaBH4 solution in step (3) is a 0.5-2M water or ethanol solution;

[0036] Preferably, the volume-to-mass ratio of the NaBH4 solution to the CdS nanomaterial in step (3) is 1-6 mL: 200-350 mg;

[0037] Preferably, the temperature of the stirring reaction in step (3) is 0-80℃, and the stirring reaction time is 1-10h;

[0038] More preferably, the temperature of the stirring reaction in step (3) is 0-40℃, and the stirring reaction time is 3-10h.

[0039] Preferably, the Bi in step (3) 3+ The source is Bi(NO3)3·5H2O.

[0040] Preferably, the single-layer two-dimensional nanosheet Ti3C2T described in step (4) X The mass ratio of CdS / Bi composite material is 0.5-55:20-100;

[0041] More preferably, the single-layer two-dimensional nanosheet Ti3C2T described in step (4) X The mass ratio of CdS / Bi composite material is 0.5-50:40-100;

[0042] Preferably, the water in step (4) is ultrapure water, and the volume-to-mass ratio of the water to the CdS / Bi composite material is 50-290 mL: 10-100 mg;

[0043] More preferably, the volume-to-mass ratio of water to CdS / Bi composite material in step (4) is 60-260 mL: 10-100 mg;

[0044] Preferably, the temperature of the stirring reaction in step (4) is 0-60℃ and the stirring reaction time is 0.5-10h.

[0045] More preferably, the temperature of the stirring reaction in step (4) is 0-40℃, and the stirring reaction time is 0.5-8h.

[0046] Preferably, the drying in steps (1), (2), (3) and (4) is drying at 40-100°C, vacuum freeze drying or vacuum drying, and the drying time is more than 6 hours.

[0047] Preferably, the washing method described in steps (2), (3) and (4) is to wash with ultrapure water 3-5 times.

[0048] The above-mentioned CdS / Bi / Ti3C2T XApplication of photocatalysts in photocatalytic organic oxidation reactions.

[0049] Preferably, the photocatalytic organic oxidation reaction includes the oxidative coupling of benzylamine and the hydroxylation of arylboronic acid;

[0050] Preferably, the photocatalytic organic oxidation reaction is carried out under light irradiation.

[0051] Further preferably, the CdS / Bi / Ti3C2T X Photocatalysts are used in the oxidative coupling reaction of benzylamine, and the general reaction formula is:

[0052]

[0053] The R mentioned 1 The compounds are selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups; the light irradiation is visible light; the reaction conditions include: the solvent is water, acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, dichloromethane, tetrahydrofuran, or dioxane, and the volume molar ratio of the solvent to compound 1 is 0.5-6 mL / mmol; the CdS / Bi / Ti3C2T X The molar ratio of the photocatalyst dosage to compound 1 was 5-35 mg / mmol;

[0054] More preferably, the volume molar ratio of the solvent to compound 1 is 0.5-5 mL / mmol; the CdS / Bi / Ti3C2T X The molar ratio of the photocatalyst to compound 1 was 10-25 mg / mmol.

[0055] More preferably, compound 1 is benzylamine or a derivative thereof;

[0056] More preferably, the number of substituents in the substituted or unsubstituted aryl group or the substituted or unsubstituted heteroaryl group is one or more, and the multiple substituents are the same or different; the substituents are hydrogen, cyano, nitro, halogen, alkyl, alkoxy, haloalkyl, heteroalkyl, or phenyl.

[0057] Further preferably, the CdS / Bi / Ti3C2T X Photocatalysts are used for the hydroxylation of arylboronic acids, and the general reaction formula is:

[0058]

[0059] The R mentioned 2The compounds are selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups; the light irradiation is visible light; the reaction conditions include: the solvent is water, acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, dichloromethane, tetrahydrofuran, or dioxane, and the volume molar ratio of the solvent to compound 3 is 0.5-6 mL / mmol; the CdS / Bi / Ti3C2T X The molar ratio of the photocatalyst to compound 3 is 5-35 mg / mmol; the additive is triethylamine, N,N-diisopropylethylamine or tripropylamine.

[0060] More preferably, the volume molar ratio of the solvent to compound 3 is 0.5-5 mL / mmol; the CdS / Bi / Ti3C2T X The molar ratio of the photocatalyst to compound 3 was 10-25 mg / mmol.

[0061] More preferably, compound 3 is phenylboronic acid and its derivatives;

[0062] More preferably, the number of substituents in the substituted or unsubstituted aryl group or the substituted or unsubstituted heteroaryl group is one or more, and the multiple substituents are the same or different; the substituents are hydrogen, cyano, nitro, halogen, aldehyde, phenyl, carbazolyl, alkyl, alkoxy, haloalkyl, or heteroalkyl.

[0063] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0064] (1) This invention solves the problem of easy recombination of charge carriers in traditional photocatalyst CdS by constructing composite materials, and at the same time utilizes Bi and Ti3C2T X As a cocatalyst, it effectively improves the separation efficiency and transport rate of photogenerated carriers in the catalyst, thus exhibiting high catalytic activity and good cycle stability.

[0065] (2) Compared with other heterogeneous photocatalysts used for borate hydroxylation, the CdS / Bi / Ti3C2T prepared in this invention has better performance. X Photocatalysts can be used as a universal photocatalyst to efficiently achieve the oxidative coupling of benzylamine and the hydroxylation of arylboronic acid.

[0066] (3) The raw materials required for this invention are cheap and readily available, and can achieve greater economic benefits with lower investment.

[0067] (4) The preparation process of this invention is simple, the operation requirements are simple, and it is easy to achieve large-scale mass production. Attached Figure Description

[0068] Figure 1The CdS / Bi / Ti3C2T prepared in Example 1 of this invention X Scanning electron microscope image of the photocatalyst.

[0069] Figure 2 Ti3C2T prepared in Example 1 of this invention X , CdS, CdS / Bi, CdS / Bi / Ti3C2T X XRD pattern of photocatalyst.

[0070] Figure 3-6 The NMR spectrum of the compound obtained in the reaction of Example 1 of this invention is shown.

[0071] Figure 7-10 This is the NMR spectrum of the compound obtained in the reaction of Example 2 of the present invention.

[0072] Figure 11-14 The NMR spectrum of the compound obtained in the reaction of Example 3 of this invention is shown.

[0073] Figure 15-18 This is the NMR spectrum of the compound obtained in the reaction of Example 4 of the present invention.

[0074] Figure 19-22 This is the NMR spectrum of the compound obtained in the reaction of Example 5 of the present invention.

[0075] Figure 23 The CdS / Bi / Ti3C2T prepared in Example 1 of this invention X Cyclic performance test diagram of photocatalyst for hydroxylation of 4-cyanobenzonic acid. Detailed Implementation

[0076] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto. For process parameters not specifically specified, conventional techniques can be referred to. Reagents or instruments whose manufacturers are not specified are considered to be conventional products that can be purchased commercially.

[0077] Example 1

[0078] CdS / Bi / Ti3C2T X Preparation of photocatalysts:

[0079] (1) Add 20 mL of concentrated hydrochloric acid with a mass fraction of 37% and 1 g of LiF powder to a polytetrafluoroethylene beaker. Stir the mixture in a constant temperature water bath at 35℃ for 30 min at a stirring speed of about 450 r / min. Then weigh 10 portions of 0.1 g Ti3AlC2 powder (total 1 g) and add them to the above system in portions over 10 min. Continue the reaction under the above conditions for 24 h. After the reaction is completed, centrifuge the reaction solution, collect the black precipitate and wash it 6-7 times with ultrapure water to obtain multilayer Ti3C2.

[0080] (2) Add the multilayered Ti3C2 (0.5g) described in step (1) to 100mL of ultrapure water, sonicate under argon atmosphere for 60min, centrifuge the dispersion and collect the supernatant, and freeze-dry the supernatant in vacuum for more than 24h to obtain a single-layered Ti3C2T X Two-dimensional nanosheets;

[0081] (3) 768 mg of Cd(NO3)2·4H2O, 568 mg of thiourea, and 20 mL of ethylenediamine were added to a polytetrafluoroethylene liner and stirred for 30 min to form a uniform suspension. Then, a solvothermal reaction was carried out in a reactor at 180 °C for 24 h. After the reaction was completed, the mixture was naturally cooled to room temperature. The bright yellow precipitate was collected by centrifugation, washed several times with ethanol and ultrapure water, and dried in an oven at 60 °C for 12 h to obtain CdS nanorods.

[0082] (4) Weigh 232 mg of Bi(NO3)3·5H2O and dissolve it in 20 mL of ethylene glycol. Then, under magnetic stirring, add 200 mg of CdS nanorods synthesized in step (3) to the mixed solution and react in an oil bath at 80 °C for 1 h. After the reaction is complete, cool naturally to room temperature, wash three times with ultrapure water and methanol respectively, and finally centrifuge the precipitate and dry it in a vacuum drying oven for 6 h. The resulting powder is dispersed in 10 mL of NaBH4 aqueous solution (1 M). After reacting under magnetic stirring at room temperature for 4 h, wash the resulting solid three times with water and methanol respectively, and dry it in a vacuum drying oven for 6 h to obtain the CdS / Bi composite material.

[0083] (5) Disperse the CdS / Bi composite material (85 mg) synthesized in step (4) in 170 mL of water, and then disperse the Ti3C2T synthesized in step (2) in the same water. X (15 mg) was dispersed in 30 mL of water, and after thorough dispersion, the mixture was stirred at room temperature for 1 h. The resulting precipitate was washed three times with ultrapure water and finally dried in a vacuum drying oven for 6 h to obtain CdS / Bi / Ti3C2T. X Photocatalyst.

[0084] CdS / Ti3C2TX Preparation of photocatalysts:

[0085] (6) Disperse the CdS nanorods (85 mg) synthesized in step (3) in 170 mL of water, and then disperse the Ti3C2T synthesized in step (2) in the same way. X (15 mg) was dispersed in 30 mL of water, and after thorough dispersion, the mixture was stirred at room temperature. The resulting precipitate was washed three times with ultrapure water and finally dried in a vacuum drying oven for 6 hours to obtain CdS / Ti3C2T. X Photocatalyst.

[0086] Bi@Ti3C2T X Preparation of / CdS complex:

[0087] (7) Dissolve 30 mg PVP and 30 mg BiCl3 in 3 mL of water and stir for 10 min. Then add 20 mg NaBH4 to the mixed solution. After the reaction is complete, add the Ti3C2T synthesized in step (2). X (43 mg), stirred for 6 h, and finally centrifuged the obtained product and dried under vacuum for 24 h to obtain Bi@Ti3C2T X Complex.

[0088] (8) Take the Bi@Ti3C2T synthesized in step (7) X The complex (15 mg) was dispersed in 8 mL of deionized water and slowly added dropwise to 15 mL of anhydrous ethanol solution containing 85 mg of CdS nanorods synthesized in step (3). The mixture was stirred for 1 h, centrifuged, and dried under vacuum for 24 h to obtain Bi@Ti3C2T X / CdS complex.

[0089] The CdS / Bi / Ti3C2T obtained in this embodiment X Scanning electron microscopy of photocatalysts, such as Figure 1 As shown, from Figure 1 It can be seen that two-dimensional CdS / Bi / Ti3C2T was successfully synthesized. X Composite material. Ti3C2T X , CdS, CdS / Bi, CdS / Bi / Ti3C2T X The XRD pattern of the photocatalyst is shown below. Figure 2 As shown, the crystallinity and composition of the aforementioned material are confirmed.

[0090] The CdS / Bi / Ti3C2T obtained in this embodiment X Photocatalysts are used in the oxidative coupling of benzylamine and the hydroxylation of arylboronic acids. Specific steps include:

[0091] (1) Add 44 μL benzylamine, 2 mL acetonitrile and 4 mg CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under a light source (40W white LED) for 4 hours. After the reaction, (E)-N-phenylmethylene-1-phenylmethylamine (2a) was obtained by column chromatography with a yield of 94%. The NMR spectra of the product are shown below. Figure 3 As shown in Figure 4, the result characterization data are as follows:

[0092]

[0093] Yield: 36.7mg (94%); Yellow liquid; 1 H NMR (400MHz, CDCl3) δ8.44(s,1H),7.84-7.81(m,2H),7.47-7.45(m,3H),7.38(d,J=4.4Hz,4H),7.34-7.28(m,1H),4.87(s,2H). 13 CNMR (100MHz, CDCl3) δ162.0,139.3,136.2,130.8,128.6,128.5,128.3,128.0,127.0,65.1.

[0094] Without adding a catalyst, and with equal masses of CdS, CdS / Bi, and CdS / Ti3C2T X Bi@Ti3C2T X / CdS replaces the above CdS / Bi / Ti3C2T X The photocatalyst was used as a control group; the other preparation processes were the same as described above, and the yield data are as follows:

[0095]

[0096]

[0097] It can be seen that: CdS / Bi / Ti3C2T X The photocatalyst exhibits optimal catalytic performance, demonstrating that our synthesis strategy effectively improves the photocatalytic efficiency of CdS.

[0098] (2) Add 29.4 mg of p-cyanobenzoic acid, 122 μL of DIPEA, 2 mL of N,N-dimethylacetamide and 2 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under light source (40W white LED) for 8 hours. After the reaction, p-cyanophenol (4a) was obtained by column chromatography with a yield of 98%. The NMR and ¹³C NMR spectra of the product are shown below. Figure 5As shown in Figure 6, the result characterization data are as follows:

[0099]

[0100] Yield: 23.3mg (98%); White solid; 1 H NMR (400MHz, CDCl3) δ7.54 (d, J=

[0101] 8.7Hz,2H),6.93(d,J=8.8Hz,2H),6.88(s,1H). 13 C NMR (100MHz, CDCl3) δ160.3,134.3,119.3,116.5,103.1.

[0102] After the reaction was completed, CdS / Bi / Ti3C2T was recovered. X The photocatalyst was prepared by repeating the above preparation process four times. Figure 23 The CdS / Bi / Ti3C2T prepared in Example 1 of this invention X The cycle performance test graph of the photocatalyst for the hydroxylation of 4-cyanoboronic acid shows that the CdS / Bi / Ti3C2T of this application... X Photocatalysts exhibit good stability.

[0103] Without adding a catalyst, and with equal masses of CdS, CdS / Bi, and CdS / Ti3C2T X Bi@Ti3C2T X / CdS replaces the above CdS / Bi / Ti3C2T X The photocatalyst was used as a control group. The reaction time was 4 hours, and the other preparation processes were the same as described above. The yield data are as follows:

[0104]

[0105]

[0106]

[0107] It can be seen that: CdS / Bi / Ti3C2T X The photocatalyst exhibits the best catalytic effect, achieving a yield of 98% after 8 hours of reaction.

[0108] Example 2

[0109] The CdS / Bi / Ti3C2T obtained in Example 1 X Photocatalysts are used in the oxidative coupling of benzylamine and the hydroxylation of arylboronic acids. Specific steps include:

[0110] (1) Add 51 μL of p-methylbenzylamine, 2 mL of acetonitrile and 4 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under a light source (40W white LED) for 4 hours. After the reaction, (E)-N-(4-methylbenzyl)-1-(p-tolyl)methylimine (2b) was obtained by column chromatography with a yield of 95%. The NMR spectra of the product are shown below. Figure 7 As shown in Figure 8, the result characterization data are as follows:

[0111]

[0112] Yield: 42.4mg (95%); White solid; 1 H NMR (400MHz, CDCl3) δ8.34(s,1H),7.66(d,J=8.0Hz,2H),7.22(d,J=6.8Hz,4H),7.15(d,J=8.0Hz,2H),4.77(s,2H),2.38(s,3H),2.34(s,3H). 13 C NMR (100MHz, CDCl3) δ161.7,141.0,136.5,136.4,133.6,132.6,129.3,129.2,128.3,128.0,64.8,21.5,21.1.

[0113] (2) Add 24 mg of phenylboronic acid, 122 μL of DIPEA, 2 mL of N,N-dimethylacetamide and 2 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under light source (40W white LED) for 8 hours. After the reaction, phenol (4b) was obtained by column chromatography with a yield of 90%. The NMR spectra of the product are shown below. Figure 9 As shown in Figure 10, the result characterization data are as follows:

[0114]

[0115] Yield: 16.9mg (90%); White solid; 1 H NMR (400MHz, CDCl) 3) δ7.32-7.25(m,2H),6.97(t,J=7.4Hz,1H),6.90-6.85(m,2H),5.12(s,1H). 13 C NMR (100MHz, CDCl3) δ155.4,129.7,120.9,115.3.

[0116] Example 3

[0117] The CdS / Bi / Ti3C2T obtained in Example 1 X Photocatalysts are used in the oxidative coupling of benzylamine and the hydroxylation of arylboronic acids. Specific steps include:

[0118] (1) Add 49 μL of p-chlorobenzylamine, 2 mL of acetonitrile and 4 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under a light source (40W white LED) for 4 hours. After the reaction, (E)-N-(4-chlorobenzyl)-1-(4-chlorophenyl)methylimine (2c) was obtained by column chromatography with a yield of 90%. The NMR spectra of the product are shown below. Figure 11 As shown in Figure 12, the result characterization data are as follows:

[0119]

[0120] Yield: 47.3mg (90%); White solid; 1 H NMR (400MHz, CDCl3) δ8.37(s,1H),7.74(J=8.8Hz,2H),7.42(J=8.4Hz,2H),7.34(J=8.4Hz,2H),7.29(J=8.4Hz,,2H),4.79(s,2H). 13 C NMR (100MHz, CDCl3) δ160.9,137.6,136.9,134.5,132.9,129.5,129.3 129.0,128.7,64.2.

[0121] (2) Add 30 mg of 1-naphthylbenzolic acid, 122 μL of DIPEA, 2 mL of N,N-dimethylacetamide and 2 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst was reacted under light source (40W white LED) for 8 hours. After the reaction, naphthol (4c) was obtained by column chromatography with a yield of 96%. The NMR spectra of the product are shown below. Figure 13 As shown in Figure 14, the result characterization data are as follows:

[0122]

[0123] Yield: 27.7mg (96%); White solid; 1H NMR (400MHz, CDCl3) δ8.20-8.18(m,1H),7.88-7.69(m,1H),7.53-7.39(m,3H),7.31(t,J=7.8Hz,1H),6.82(dd,J=7.4,0.8Hz,1H),5.46(s,1H). 13 C NMR (100MHz, CDCl3) δ151.4,134.8,127.7,126.5,125.9,125.3,124.4,121.6,120.7,108.6.

[0124] Example 4

[0125] The CdS / Bi / Ti3C2T obtained in Example 1 X Photocatalysts are used in the oxidative coupling of benzylamine and the hydroxylation of arylboronic acids. Specific steps include:

[0126] (1) Add 51 μL of p-methylbenzylamine, 2 mL of acetonitrile and 4 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under a light source (40W white LED) for 4 hours. After the reaction, (E)-N-(4-bromobenzyl)-1-(4-bromophenyl)methylimine (2d) was obtained by column chromatography with a yield of 95%. The NMR spectra of the product are shown below. Figure 15 As shown in Figure 16, the result characterization data are as follows:

[0127]

[0128] Yield: 67.0mg (95%); White solid; 1 H NMR (400MHz, CDCl3) δ8.35 (s, 1H), 7.68 (d, J = 8.4Hz, 2H), 7.58 (d, J = 8.4Hz, 2H), 7.49 (d, J = 8.4Hz, 2H), 7.23 (d, J = 8.4Hz, 2H), 4.77 (s, 2H). 13 C NMR (100MHz, CDCl3) δ161.0,138.1,134.9,131.9,131.6,129.7,129.7,125.4,121.0,64.2.

[0129] (2) Add 33 mg of p-nitrophenylboronic acid, 122 μL of DIPEA, 2 mL of N,N-dimethylacetamide and 2 mg of CdS / Bi / Ti3C2T to the flask. XThe photocatalyst reacted under light source (40W white LED) for 8 hours. After the reaction, p-nitrophenol was obtained by column chromatography (4d), with a yield of 97%. The NMR spectra of the product are shown below. Figure 17 As shown in Figure 18, the result characterization data are as follows:

[0130]

[0131] Yield: 27.0mg (97%); Faint yellow solid; 1 H NMR (400MHz, CDCl3) δ8.25-8.10(m,2H),6.96-6.81(m,2H),6.18(s,1H). 13 C NMR (100MHz, CDCl3) δ162.1,141.3,126.3,115.7.

[0132] Example 5

[0133] The CdS / Bi / Ti3C2T obtained in Example 1 X Photocatalysts are used in the oxidative coupling of benzylamine and the hydroxylation of arylboronic acids. Specific steps include:

[0134] (1) Add 50 μL of o-benzyl bromide, 2 mL of acetonitrile, and 4 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under a light source (40W white LED) for 4 hours. After the reaction, (E)-N-(2-bromobenzyl)-1-(2-bromophenyl)methylimine (2e) was obtained by column chromatography with a yield of 94%. The NMR spectra of the product are shown below. Figure 19 As shown in Figure 20, the result characterization data are as follows:

[0135]

[0136] Yield: 66.4mg (94%); Brown solid; 1 H NMR (400MHz, CDCl3) δ8.84(s,1H),8.14(dd,J=7.6,1.6Hz,1H),7.61(dd,J=8.0,1.2Hz ,2H),7.46(dd,J=7.6,1.2Hz,1H),7.42-7.28(m,3H),7.20-7.15(m,1H),4.96(s,2H). 13C NMR (100MHz, CDCl3) δ162.1,138.5,134.5,133.1,132.7,132.0,129.8,128.9,128.6,127.7,127.6,125.3,123.7,64.4.

[0137] (2) Add 40 mg of p-phenylphenylboronic acid, 122 μL of DIPEA, 2 mL of N,N-dimethylacetamide and 2 mg of CdS / Bi / Ti3C2T to the flask. X The photocatalyst reacted under a light source (40W white LED) for 8 hours. After the reaction, p-phenylphenol (4e) was obtained by column chromatography with a yield of 94%. The NMR spectra of the product are shown below. Figure 21 As shown in Figure 22, the result characterization data are as follows:

[0138]

[0139] Yield: 32.0mg (94%); White solid; 1 H NMR (400MHz, CDCl3) δ7.56-7.53(m,2H),7.51-7.46(m,2H),7.42(t,J=7.6Hz,2H),7.34-7.28(m,1H),6.94-6.88(m,2H),5.01(s,1H). 13 C NMR (100MHz, CDCl3) δ155.1,140.8,134.0,128.7,128.4,126.7,126.7,115.7.

[0140] The above embodiments are only used to explain the present invention and are not intended to limit the present invention in any way. Any simplifications, modifications, substitutions, and combinations made by those skilled in the art to the above embodiments based on the spirit and technical principles of the present invention without departing from the scope of the present invention should fall within the protection scope of the present invention.

Claims

1. A CdS / Bi / Ti3C2T X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, Its general reaction formula is: The R mentioned 2 Selected from substituted or unsubstituted aryl groups, and substituted or unsubstituted heteroaryl groups; irradiation is visible light; the reaction conditions include: the solvent is water, acetonitrile, N,N - Dimethylformamide, dimethyl sulfoxide, dichloromethane, tetrahydrofuran or dioxane, the volume molar ratio of the solvent to compound 3 is 0.5-6 mL / mmol; the CdS / Bi / Ti3C2T X The molar ratio of the photocatalyst to compound 3 was 5-35 mg / mmol; the additive was triethylamine. N , N -Diisopropylethylamine or tripropylamine; The CdS / Bi / Ti3C2T X The photocatalyst is a ternary composite material consisting of CdS nanorods, Bi nanosheets, and two-dimensional nanosheets Ti3C2T. X Composition: Bi nanosheets are formed on the surface of CdS nanorods through in-situ reduction via ion exchange, and the CdS nanorods are uniformly distributed on the two-dimensional nanosheets Ti3C2T. X superior.

2. The CdS / Bi / Ti3C2T according to claim 1 X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, The CdS / Bi / Ti3C2T X The preparation method of photocatalyst includes the following steps: (1) After removing the Al layer of Ti3AlC2 with LiF and HCl, it was ultrasonically treated in water under inert gas protection, and the supernatant was collected by centrifugation and dried to obtain a single layer of two-dimensional nanosheets Ti3C2T X ; (2) Place Cd 2+ After stirring, CdS nanomaterials were formed by dispersing thiourea and ethylenediamine and then undergoing a solvothermal reaction. After the reaction was completed, the nanomaterials were washed and dried to obtain CdS nanomaterials. (3) The CdS nanomaterials prepared in step (2) and Bi 3+ The source was added to ethylene glycol and heated to react. After the reaction was completed, the mixture was washed and dried. The resulting solid was redissolved in a solution of NaBH4 and stirred to react. After the reaction was completed, the mixture was washed and dried to obtain the CdS / Bi composite material. (4) The monolayer two-dimensional nanosheets Ti3C2T prepared in step (1) X The CdS / Bi composite material prepared in step (3) was added to water, stirred, and reacted. After the reaction was completed, the mixture was washed and dried to obtain CdS / Bi / Ti3C2T. X Photocatalyst.

3. The CdS / Bi / Ti3C2T according to claim 2 X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, The method for removing the Al layer from Ti3AlC2 using LiF and HCl in step (1) is as follows: LiF powder is added to concentrated hydrochloric acid and stirred for 20-70 min in a constant temperature water bath at 20-50℃; then Ti3AlC2 powder is added to the solution in portions, and the reaction continues for 20-72 h at a stirring speed of 380-800 r / min. After the reaction is completed, the reaction solution is centrifuged, the black precipitate is collected, and washed 5-10 times with ultrapure water; the volume-to-mass ratio of concentrated hydrochloric acid to Ti3AlC2 powder is 2-20 mL: 1 g; the concentration of concentrated hydrochloric acid is 36%-38%; the mass ratio of LiF to Ti3AlC2 is 1-3: 0.5-3.

5. The ultrasonic treatment time in step (1) is 20-100 min; the centrifugation speed is 2800-5000 rpm; the water is ultrapure water; and the inert gas is argon or nitrogen.

4. A CdS / Bi / Ti3C2T according to claim 2 X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, Step (2) Cd 2+ The mass ratio of the source and thiourea is 550-800:550-800; the ethylenediamine and Cd 2 + The volume-to-mass ratio of the source is 10-30 mL: 0.5-1 g; the stirring time is 10-60 min; the solvothermal reaction temperature is 100-200 ℃, and the solvothermal reaction time is 12-36 h; the Cd 2+ The source is Cd(NO3)2•4H2O.

5. A CdS / Bi / Ti3C2T according to claim 2 X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, Step (3) Bi 3+ The mass ratio of the source to CdS nanomaterials is 200-350:200-350; the volume-to-mass ratio of the ethylene glycol to CdS nanomaterials is 5-40 mL:0.1-0.5 g; the heating reaction temperature is 30-100 ℃; the heating reaction time is 1-5 h; the NaBH4 solution is a 0.1-5 M water or ethanol solution; the volume-to-mass ratio of the NaBH4 solution to CdS nanomaterials is 1-6 mL:200-350 mg; the stirring reaction temperature is 0-80 ℃, and the stirring reaction time is 1-10 h; the Bi 3+ The source is Bi(NO3)3•5H2O.

6. A CdS / Bi / Ti3C2T according to claim 2 X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, Step (4) describes the single-layer two-dimensional nanosheet Ti3C2T X The mass ratio of water to CdS / Bi composite material is 0.5-55:20-100; the water is ultrapure water, and the volume-to-mass ratio of water to CdS / Bi composite material is 50-290 mL:10-100 mg; the temperature of the stirring reaction is 0-60 ℃, and the stirring reaction time is 0.5-10 h.

7. A CdS / Bi / Ti3C2T according to claim 2 X The application of photocatalysts in the hydroxylation of arylboronic acids is characterized by, The drying described in steps (1), (2), (3) and (4) is drying at 40-100 °C, vacuum freeze drying or vacuum drying, and the drying time is more than 6 hours; The washing method described in steps (2), (3) and (4) is to wash with ultrapure water 3-5 times.

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