CN115463689A - Method for catalyzing Suzuki-Miyaura coupling reaction by cellulose aerogel supported catalyst - Google Patents

Abstract

The invention discloses a method for catalyzing Suzuki-Miyaura coupling reaction with a cellulose airgel supported catalyst, comprising the following steps: S1, preparing cellulose airgel (GPA); S2, preparing modified cellulose airgel ( M-GPA): put the cellulose airgel obtained in step S1 into a beaker containing absolute ethanol, glacial acetic acid, and methyltrimethoxysilane mixture, and soak for 8-10h at room temperature; after soaking, use Wash with distilled water until neutral, then replace with tert-butanol, place at room temperature for 12 hours, freeze in the refrigerator for 24 hours, take it out, put it in a freeze dryer, freeze-dry it at 80°C for 72 hours, and take it out to obtain modified cellulose airset glue. The present invention adopts the above-mentioned method for catalyzing the Suzuki-Miyaura coupling reaction with a cellulose airgel-supported catalyst, while ensuring the yield of the Suzuki-Miyaura coupling reaction, it realizes multiple recycling of the palladium acetate catalyst, greatly reducing the Reduced the test cost, and promoted the research and application of supported palladium acetate.

Description

A cellulose airgel-supported catalyst catalyzes the Suzuki-Miyaura coupling reaction Methods

technical field

The invention relates to the technical field of catalyst immobilization, in particular to a method for catalyzing a Suzuki-Miyaura coupling reaction with a cellulose airgel-supported catalyst.

Background technique

At present, the Suzuki-Miyaura coupling reaction has the advantages of wide application of substrates, mild reaction conditions, stability to heat, air and water, and most of the by-products are non-toxic and easy to post-process. It has been widely used in the industrial synthesis of drugs.

The catalytic cycle process of Suzuki-Miyaura coupling reaction generally includes elementary reactions such as oxidative addition, metal transfer and reductive elimination. The catalytic cycle begins with an oxidative addition reaction between an organic electrophile and zero-valent palladium to generate a R ₁ -Pd-X divalent palladium intermediate, and then undergoes a metal transfer reaction with an organoboride to generate a R ₁ -Pd-R ₂ intermediate , and finally the coupling product R ₁ -R ₂ is obtained through reduction and elimination, and at the same time, the zero-valent palladium is released to participate in the catalytic cycle again.

However, during the Suzuki-Miyaura coupling reaction catalyzed by palladium acetate, palladium black is easily formed, which not only affects the experiment, lowers the yield, but also increases the consumption of palladium acetate. However, palladium acetate is expensive, and a large amount of consumption will increase the cost of the experiment.

Most of the current supported palladium acetate uses silica gel, and the conversion rate of the Suzuki-Miyaura coupling reaction is far inferior to that of homogeneous palladium acetate.

Contents of the invention

The object of the present invention is to provide a kind of method of cellulose airgel supported catalyst catalysis Suzuki-Miyaura coupling reaction, has solved the consumption of palladium acetate in the above-mentioned background technology is big, and experiment cost is high, the problem of load-type palladium acetate conversion rate is low .

To achieve the above object, the invention provides a method for catalyzing the Suzuki-Miyaura coupling reaction of a cellulose airgel supported catalyst, comprising the steps of:

S1, preparing cellulose airgel (GPA);

S2. Preparation of modified cellulose airgel (M-GPA): put the cellulose airgel obtained in step S1 into a beaker containing a mixture of absolute ethanol, glacial acetic acid, and methyltrimethoxysilane at room temperature Soak under water for 8-10 hours; after soaking, wash with distilled water until neutral, then replace with tert-butanol, place at room temperature for 12 hours, freeze in the refrigerator for 24 hours, take it out, put it in a freeze dryer, and freeze-dry it at 80°C Take it out after 72h to obtain the modified cellulose airgel;

S3, palladium acetate immobilization (preparation catalyst Pd/M-GPA): 5 ~ 10mg palladium acetate is dissolved in 5 ~ 15mL methylene chloride, put in the beaker, then add 35 ~ 45mg modified cellulose airgel, use Seal the beaker with plastic wrap and put it into a low-temperature and constant-temperature stirring reaction bath at a fixed speed, stir for 16-24 hours, and then dry it at room temperature for 24 hours to obtain the catalyst Pd/M-GPA.

Preferably, in step S1, the preparation process of cellulose airgel (GPA) is as follows: fresh pomelo peel is cut into a suitable size cuboid block, placed in a beaker, sealed with a plastic wrap and put into a lyophilizer. After freeze-drying at ℃ for 4 days, the cellulose aerogel was obtained.

Preferably, the steps of the Suzuki-Miyaura coupling reaction are: adding aryl halides, phenylboronic acid, potassium carbonate, and Pd/M-GPA to p-xylene in sequence, and in an ambient air reflux atmosphere at 130-150 ° C, 300R stirred and reacted for 20-60 minutes; after the reaction was completed (detected by TLC), the catalyst Pd/M-GPA was taken out; then the organic phase was evaporated under reduced pressure to leave the crude product, which was further purified by silica gel column chromatography to obtain the desired cross coupling product.

Preferably, the mass fractions of absolute ethanol, glacial acetic acid, and methyltrimethoxysilane in the mixed liquid are respectively: absolute ethanol 97wt%, glacial acetic acid 1wt%, and methyltrimethoxysilane 1wt%.

Preferably, in step S3, the added amount of palladium acetate is 0.01%-0.015% of the molar amount of phenylboronic acid.

Preferably, in step S3, the mass fraction of the modified pomelo airgel is 0.3-0.7 wt%.

Preferably, in step S3, the temperature of the low-temperature and constant-temperature stirring reaction bath is set at 20-25°C.

Therefore, the present invention adopts the above-mentioned method for catalyzing the Suzuki-Miyaura coupling reaction of a kind of cellulose airgel supported catalyst, while ensuring the Suzuki-Miyaura coupling reaction productive rate, realized multiple recycling of palladium acetate catalyst, The test cost is greatly reduced, and the research and application of supported palladium acetate are promoted simultaneously.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

Fig. 1 is the scanning electron micrograph of different magnifications of pomelo peel airgel before and after modification in the method for catalyzing Suzuki-Miyaura coupling reaction of a kind of cellulose airgel supported catalyst of the present invention;

Fig. 2 is a kind of cellulose airgel supported catalyst of the present invention in the method for catalyzing Suzuki-Miyaura coupling reaction, before and after modification pomelo airgel adsorption Pd (OAc) Scanning electron micrographs of different magnifications;

Fig. 3 is the XRD spectrum of the pomelo peel cellulose airgel before and after modification in the method for catalyzing Suzuki-Miyaura coupling reaction of a kind of cellulose airgel supported catalyst of the present invention;

Fig. 4 is the XRD spectrum of the pomelo peel cellulose airgel adsorbed palladium acetate before and after modification of a method embodiment of the Suzuki-Miyaura coupling reaction catalyzed by a cellulose airgel supported catalyst of the present invention;

Fig. 5 is a catalytic cycle test of catalyst Pd/M-GPA-1 in a method for catalyzing Suzuki-Miyaura coupling reaction with a cellulose airgel-supported catalyst of the present invention.

detailed description

The technical solutions of the present invention will be further described below through the accompanying drawings and embodiments.

Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by those skilled in the art to which the present invention belongs.

Embodiment one

A method for catalyzing the Suzuki-Miyaura coupling reaction with a cellulose airgel supported catalyst, comprising the steps of:

S1. Preparation of pomelo peel aerogel (GPA): Cut fresh pomelo peel into 2.5cm×2.8cm×1.8cm regular cuboid block, put it in a 50mL plastic beaker, seal it with plastic wrap and put it in a freeze dryer. After being freeze-dried at 80°C for 4 days, it was taken out to obtain pomelo peel airgel;

S2. Preparation of modified pomelo peel airgel (M-GPA): put the pomelo peel aerogel obtained in S1 into a beaker containing a mixture of 97mL absolute ethanol, 1mL glacial acetic acid and 1mL methyltrimethoxysilane medium, soak at room temperature for 9 hours; after soaking, wash with distilled water until neutral, then replace with tert-butanol, place at room temperature for 12 hours, freeze in the refrigerator for 24 hours, take it out, put it in a freeze dryer, and freeze at 80°C Take it out after drying for 72 hours to obtain methyltrimethoxysilane modified pomelo peel airgel (M-GPA-1);

S3. Palladium acetate fixation (preparation of catalyst Pd/M-GPA): Dissolve 5 mg of palladium acetate in 5 mL of dichloromethane, place in a 50 mL beaker, then add 37 mg of M-GPA, seal the beaker with plastic wrap and put it in low temperature In the constant-temperature stirring reaction bath, the temperature of the low-temperature constant-temperature stirring reaction bath was set at 20° C., the rotation speed was fixed, and the mixture was stirred for 24 hours; then it was dried at room temperature for 24 hours to obtain the catalyst Pd/M-GPA-1.

In step S3, the amount of palladium acetate added is 0.01%-0.015% of the molar amount of phenylboronic acid when the Suzuki-Miyaura coupling reaction is carried out, and the mass fraction of the modified pomelo airgel is 0.3-0.7 wt%.

Embodiment two

The same experimental conditions as in Example 1, palladium acetate was loaded on the unmodified pomelo peel aerogel to obtain Pd/GPA.

Embodiment three

The same experimental conditions as in Example 1, using sodium sulfide to modify pomelo peel aerogel, the specific steps are as follows:

On the basis of the pomelo peel airgel obtained in step S1, according to the pomelo peel aerogel: sodium sulfide solution=1:5, add a sodium sulfide solution with a concentration of 1.5mol/L, stir evenly with a glass rod, and After standing for 12 hours, wash with distilled water several times until neutral, and test with pH test paper.

After washing with water until neutral, replace it with tert-butanol, place it at room temperature for 12 hours, put it in the refrigerator for 24 hours, take it out, put it in a freeze dryer, and freeze it at 80°C for 72 hours, then take it out, and you can get sodium sulfide Modified pomelo peel airgel (M-GPA-2).

Then according to the steps of Example 1 S3, palladium acetate was loaded on the pomelo peel airgel modified with sodium sulfide to obtain the catalyst Pd/M-GPA-2.

Embodiment four

The same experimental conditions as in Example 1, using potassium hydroxide to modify pomelo peel aerogel, the specific steps are as follows:

On the basis of the pomelo airgel obtained in step S1, use KOH as the active agent, mix the pomelo airgel with potassium hydroxide (25%) solution at a mass ratio of 1:3, and soak at room temperature for 12 hours Afterwards, wash with distilled water several times until neutral, and check with pH test paper.

After washing with water until neutral, replace it with tert-butanol, place it at room temperature for 12 hours, put it in the refrigerator for 24 hours, take it out and put it in a freeze dryer, freeze-dry it at 80°C for 72 hours, and then take it out to obtain Potassium-modified pomelo peel airgel (M-GPA-3).

According to the steps of Example 1 S3, palladium acetate was loaded on pomelo peel airgel modified with potassium hydroxide to obtain catalyst Pd/M-GPA-3.

Embodiment five

The same experimental conditions as in Example 1, using dipotassium hydrogen phosphate to modify pomelo peel aerogel, the specific steps are as follows:

On the basis of the pomelo peel airgel obtained in step S1, with K ₂ HPO ₄ as the active agent, mix the pomelo peel aerogel with dipotassium hydrogen phosphate (25%) solution in a mass ratio of 1:3, at room temperature After soaking for 12 hours, wash with distilled water several times until neutral, and test with pH test paper.

After washing with water to neutrality, replace it with tert-butanol, place it at room temperature for 12 hours, put it in the refrigerator for 24 hours, take it out, put it in a freeze dryer, and freeze it at 80°C for 72 hours, and then take it out to obtain hydrogen phosphate Dipotassium modified pomelo peel airgel (M-GPA-4).

According to the steps of Example 1 S3, palladium acetate was loaded on pomelo peel airgel modified with potassium hydroxide to obtain catalyst Pd/M-GPA-4.

Experimental test

(1) The powdery samples of pomelo peel aerogel and modified pomelo peel aerogel were scanned by electron microscope at different magnifications. As shown in Figure 1, a and b are electron micrographs of pomelo peel airgel before modification; c is an electron micrograph of pomelo peel aerogel modified with methyltrimethoxysilane; d is a partial enlarged view of figure c; e and f are electron micrographs of pomelo peel airgel modified by sodium sulfide; g are electron micrographs of pomelo peel airgel modified by potassium hydroxide; h is a partial enlarged view of figure g; i is dipotassium hydrogen phosphate modified Electron micrograph of pomelo peel airgel; j is a partial enlarged view of figure i.

The results show that the pomelo peel aerogel before modification has a honeycomb porous structure with a large number of microscopic channels, and the internal pore shapes are different. The layered structure is closely arranged, and the honeycomb structure is relatively loose. The surface of the modified pomelo airgel showed a 3D interconnected porous structure with many uniformly distributed small pores and presented irregularly shaped plant flake tissue. Each porous structure is loosely filled with open spaces. It is proved that the modification effect of the modifying agent on pomelo peel aerogel is better in the examples.

(2) The catalysts Pd/GPA and Pd/M-GPA were tested by scanning electron microscopy. As shown in Figure 2, a, b are SEM images of Pd/GPA; c, d are SEM images of Pd/M-GPA-1; e, f are SEM images of Pd/M-GPA-2; g, h SEM images of Pd/M-GPA-3; i, j are SEM images of Pd/M-GPA-4.

Compared with the SEM images of unadsorbed palladium acetate in Figure 1, palladium acetate was loaded on pomelo peel airgel and modified pomelo peel aerogel to generate catalysts Pd/GPA and Pd/M-GPA, and the catalyst Pd/ The morphology of GPA and Pd/M-GPA has almost no obvious change with GPA and M-GPA, and still presents a three-dimensional network porous space structure and regular-shaped plant flake tissue. It shows that after the carrier GPA and M-GPA supported palladium acetate to form the catalyst, the original morphology and structure are still maintained.

(3) The XRD patterns of pomelo peel airgel and modified pomelo peel aerogel, catalysts Pd/GPA and Pd/M-GPA were tested respectively, as shown in Figure 3 and Figure 4.

As can be seen from the figure, the diffraction peaks of the carrier GPA and M-GPA and the catalyst Pd/GPA and Pd/M-GPA are consistent, indicating that after palladium acetate and GPA coordinate with M-GPA, the crystals of GPA and M-GPA The structure was not damaged. Moreover, the new characteristic diffraction peak of Pd/GPA at 2θ=38.78° is the (111) crystal plane of Pd(II), and the new characteristic diffraction peak of Pd/M-GPA at 2θ=39.06° is the crystal plane of Pd(II). (111) crystal plane. Therefore, it further shows that palladium acetate has been attached to the pomelo peel airgel before and after modification, and the catalysts Pd/GPA and Pd/M-GPA are generated.

(4) Put Pd/GPA and Pd/M-GPA two kinds of catalysts into the Suzuki coupling reaction with bromobenzene (39mg, 0.25mmol) and phenylboronic acid (61mg, 0.5mmol) as the reactant respectively, and pass gas chromatography (GC) analysis, calculate yield, obtain the catalyzer of optimum reaction.

The experimental steps of the Suzuki-Miyaura coupling reaction are as follows: add aryl halides, phenylboronic acid, potassium carbonate, and Pd/M-GPA to p-xylene in sequence, and stir the reaction at 130-150°C for 20~ 60 minutes; After the reaction was completed (detected by TLC), the catalyst Pd/M-GPA was taken out; then the organic phase was evaporated under reduced pressure to leave the crude product, which was further purified by silica gel column chromatography to obtain the desired cross-coupling product.

The Suzuki-Miyaura coupling reaction was as follows, different catalysts were used in this process, and the results are shown in Table 1.

Catalyst selection in Table 1 Suzuki coupling reaction

As can be seen from Table 1, the effect of the Suzuki coupling reaction catalyzed by the catalyst Pd/M-GPA-1 is the best, and the cross-coupling product is provided with excellent yield (96%), which proves that the methyl Trimethoxysilane modified pomelo airgel has the best effect of supporting catalyst.

(5) Using the Pd/M-GPA-1 prepared in Example 1 as a catalyst, taking the Suzuki-Miyaura coupling reaction of bromobenzene and phenylboronic acid as a model reaction, the expansion of the reactant substrate was carried out, and K ₂ CO ₃ and p-xylene were used as base and solvent to test the activity of the catalyst.

The Suzuki-Miyaura coupling reaction is as follows. In this process, Pd/M-GPA-1 was used as a catalyst to conduct a catalytic activity test. The results are shown in Table 2.

Table 2 Catalytic activity test of Pd/M-GPA-1 in Suzuki-Miyaura coupling reaction

Entry^a R₁ x Yield(%)^b 1 h Br 96% 2 h I 97% 3 f Br 94% 4 Cl Br 94% 5 NO₂ Br 91% 6 OCF₃ Br 96% 7 CN Br 76%

It can be seen from Table 2 that when the catalyst Pd/M-GPA-1 catalyzes the Suzuki-Miyaura coupling reaction, the substitution functional group of the aryl halide has an impact on the rate of the coupling reaction, and the order of difficulty of the reaction is RI> RBr (Entry 1-2), and provided the cross-coupling product in excellent yield (96-97%). Next, the electronic effects of different substituents of aryl bromides were explored. In the presence of electron-withdrawing groups, such as fluorine, chlorine, nitro, trifluoromethoxy (Entry3-6), with excellent yield The cross-coupling product was obtained with a high rate (91-96%), indicating that the benzene ring of the substrate bromobenzene compound is connected with an electron-withdrawing group, which is beneficial to the coupling reaction.

Among them, the yield of coupling products obtained by the Suzuki-Miyaura coupling reaction of brominated arenes with electron-withdrawing groups (-CN) is lower than that of other electron-withdrawing groups, because the electron-withdrawing groups in 4-bromobenzonitrile The positioning effect of the group is the meta-position of the benzene ring, there is a -CH ₂ between -CN and the benzene ring, so the positioning group is actually -CH ₂ CN, which only has an electron-withdrawing induction effect, but no electron-withdrawing conjugation effect , is an ortho-para positioning group of a passivated benzene ring. The above results indicated that the catalyst Pd/M-GPA-1 had high catalytic activity in catalyzing the Suzuki-Miyaura coupling reaction.

(6) Catalytic cycle test of catalyst Pd/M-GPA-1.

Using bromobenzene (39mg, 0.25mmol), phenylboronic acid (61mg, 0.5mmol), potassium carbonate (138mg, 1.0mmol), Pd/M-GPA-1 (35mg, 1.0mol%) and 4mL p-xylene at 140°C The reaction mixture was stirred under reflux for 20 minutes under ambient atmosphere. After the reaction, the catalyst Pd/M-GPA-1 was taken out, rinsed and extracted with ethyl acetate, and the recovered catalyst was dried at room temperature for 24 hours, and then used directly. The product was extracted with ethyl acetate, analyzed by gas chromatography (GC), and the yield was calculated. Under the same conditions, the catalyst was used four times in a row. Among them, bromobenzene can be replaced by other reactant substrates for catalytic cycle experiments.

The results of catalytic cycle experiments with different reactant substrates are shown in Figure 5, a is the catalytic cycle of bromobenzene, b is the catalytic cycle of iodobenzene, c is the catalytic cycle of 1-bromo-4-fluorobenzene, and d is 4 - the catalytic cycle of bromochlorobenzene, e is the catalytic cycle of 1-bromo-4-(trifluoromethoxybenzene), f is the catalytic cycle of 1-bromo-4-nitrobenzene, g is the catalytic cycle of 4-bromobenzonitrile catalytic cycle.

It can be seen from the figure that in the catalytic process, the catalytic activity of the catalyst Pd/M-GPA-1 does not decrease significantly until it is used continuously for 3 to 4 times. However, the activity of ordinary palladium catalysts decreases very quickly during use, and basically needs to be activated again after one use to participate in the reaction.

The reason for the decline in the catalytic activity of the catalyst Pd/M-GPA-1 in this experiment is that the halogenated aromatic hydrocarbons in the Suzuki-Miyaura coupling reaction interact with the catalyst first, and the halogenated aromatic hydrocarbons will be adsorbed on the active sites on the surface of the nanoparticles. These active sites are mainly at the edge points and vertices of the nanoparticles, where the adsorption performance is the lowest. Secondly, the agglomeration and dissociation of palladium nano-catalysts also have a certain impact on the catalytic activity of the catalyst. When the nano-palladium particles are heated, the palladium atoms on the surface of the catalyst detach from the particles and enter the solution. A dynamic equilibrium is formed on the surface of the palladium particles, and the increase of the ambient temperature promotes the agglomeration of nano-palladium particles, forming large particles of nano-palladium particles, reducing the catalytic activity, and even forming palladium black and deactivating it.

Therefore, the present invention adopts the above-mentioned method for catalyzing the Suzuki-Miyaura coupling reaction with a cellulose airgel-supported catalyst, while ensuring the Suzuki-Miyaura coupling reaction productivity, realizes multiple recycling of the palladium acetate catalyst, greatly The test cost is reduced, and the research and application of supported palladium acetate are promoted at the same time.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: it still Modifications or equivalent replacements can be made to the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims (8)

1. A method for catalyzing Suzuki-Miyaura coupling reaction by using cellulose aerogel supported catalyst is characterized by comprising the following steps: the method comprises the following steps:

s1, preparing cellulose aerogel (GPA);

s2, preparing modified cellulose aerogel (M-GPA): putting the cellulose aerogel obtained in the step S1 into a beaker containing a mixed solution of absolute ethyl alcohol, glacial acetic acid and methyltrimethoxysilane, and soaking for 8-10h at room temperature; after soaking, washing the mixture with distilled water to be neutral, replacing the neutral solution with tert-butyl alcohol, standing the mixture at room temperature for 12 hours, freezing the mixture in a refrigerator for 24 hours, taking the mixture out, putting the mixture into a freeze dryer, and freeze-drying the mixture at 80 ℃ for 72 hours, and taking the mixture out to obtain modified cellulose aerogel;

s3, fixing palladium acetate (preparing a catalyst Pd/M-GPA): dissolving 5-10 mg of palladium acetate in 5-15 mL of dichloromethane, placing the dichloromethane in a beaker, adding 35-45 mg of modified cellulose aerogel, sealing the beaker by using a preservative film, placing the beaker in a low-temperature constant-temperature stirring reaction bath, fixing the rotating speed, stirring for 16-24 h, and then placing the beaker at room temperature for drying for 24h to obtain the catalyst Pd/M-GPA.

2. The method for catalyzing Suzuki-Miy aura coupling reaction by using the cellulose aerogel supported catalyst according to claim 1, wherein the method comprises the following steps: in step S1, the preparation process of the cellulose aerogel (GPA) is: cutting fresh pomelo peel into cuboid blocks with proper size, placing the cuboid blocks into a beaker, sealing the opening by using a preservative film, placing the beaker into a freeze dryer, freeze-drying the pomelo peel for 4 days at 80 ℃, and taking out the pomelo peel to obtain the cellulose aerogel.

3. The method for catalyzing Suzuki-Miy aura coupling reaction by using the cellulose aerogel supported catalyst according to claim 1, wherein the method comprises the following steps: the Suzuki-Miyaura coupling reaction comprises the following steps: sequentially adding aryl halide, phenylboronic acid, potassium carbonate and Pd/M-GPA into p-xylene, and stirring and reacting for 20-60 minutes at 130-150 ℃ in an ambient atmosphere reflux atmosphere; after the reaction was completed (detected by TLC), the catalyst Pd/M-GPA was removed; the organic phase was then evaporated under reduced pressure leaving the crude product which was further purified by silica gel column chromatography to give the desired cross-coupled product.

4. The method for catalyzing Suzuki-Miy aura coupling reaction by using the cellulose aerogel supported catalyst according to claim 1, wherein the method comprises the following steps: the mass fractions of the absolute ethyl alcohol, the glacial acetic acid and the methyltrimethoxysilane in the mixed solution are respectively as follows: 97wt% of absolute ethyl alcohol, 1wt% of glacial acetic acid and 1wt% of methyltrimethoxysilane.

5. The method for catalyzing Suzuki-Miy aura coupling reaction by using the cellulose aerogel supported catalyst according to claim 3, wherein the method comprises the following steps: in the step S3, the adding amount of the palladium acetate is 0.01-0.015 percent of the molar amount of the phenylboronic acid.

6. The method for catalyzing Suzuki-Miy aura coupling reaction by using the cellulose aerogel supported catalyst according to claim 1, wherein the method comprises the following steps: in the step S3, the modified cellulose aerogel accounts for 0.3-0.7 wt% of the mass fraction.

7. The method for catalyzing Suzuki-Miy aura coupling reaction by using the cellulose aerogel supported catalyst according to claim 1, wherein the method comprises the following steps: in step S3, the temperature of the low-temperature constant-temperature stirring reaction bath is set to be 20-25 ℃.

8. Application of modified cellulose aerogel supported palladium acetate in catalyzing Suzuki-Miyaura coupling reaction.

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