Green preparation process for synthesizing 4 '-chloro-2-aminobiphenyl by membrane method

Abstract

The invention relates to the technical field of catalysis, in particular to a green preparation process for synthesizing 4 '-chloro-2-aminobiphenyl through a membrane method.A palladium-based catalytic membrane is prepared through an impregnation method, by means of the multi-pore-channel advantage of a ceramic membrane, active components can be well distributed on the surface and in the membrane, contact of a reaction substrate and active sites is promoted, and the catalytic activity of 4'-chloro-2-aminobiphenyl is improved. The reaction effect is enhanced, the reaction efficiency is improved, the preparation process is simple, the preparation environment is mild, and large-scale production can be realized; meanwhile, the 4 '-chloro-2-aminobiphenyl is prepared by adopting a method for carrying out Suzuki-Miyaura coupling reaction by adopting the catalytic membrane, tedious steps in the traditional industry are omitted, compared with a traditional heterogeneous catalyst, the trouble of recovery is avoided, the cost is saved, the harm to the environment is greatly reduced, and compared with the prior art, the 4'-chloro-2-aminobiphenyl has a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the field of catalytic technology, and particularly to a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by a membrane method. Background Art

[0002] Boscalid is a new type of nicotinamide fungicide developed by BASF in Germany. It is mainly used for controlling powdery mildew, gray mold, various rot diseases, brown rot and root rot, etc., and has been registered in the UK, Germany and Switzerland in 2004. Boscalid belongs to the inhibitor of succinate coenzyme Q reductase in the mitochondrial respiratory chain, has a strong inhibitory ability on spore germination, and has no cross-resistance with other fungicides.

[0003] 4'-Chloro-2-aminobiphenyl is a key intermediate for synthesizing boscalid and can be obtained in one step through Suzuki coupling. Currently, the synthesis routes reported in most literatures are the following two: one is to carry out Suzuki coupling between o-nitrochlorobenzene and 4-chlorophenylboronic acid and then reduce it to amine; another method is to directly carry out Suzuki coupling between o-iodoaniline and 4-chlorophenylboronic acid. The former needs to be carried out in two steps, and the second step uses iron powder reduction, resulting in a large amount of metal residues and low yield, which is not suitable for industrial production; although the latter can obtain the product in one step, the Pd(PPh3)4 catalyst used is expensive and the reaction conditions are harsh. From the economic and reaction conditions, it cannot be well industrialized.

[0004] Heterogeneous catalysts play an increasingly important role in current industrial production because their recyclability solves problems such as high cost and environmental pollution. Most traditional heterogeneous catalysts are in powder form, and their powder form also brings other problems, such as difficulties in transportation, reaction equipment and recycling.

[0005] In the prior art, homogeneous catalysts are mostly used for Suzuki reactions, but problems such as high catalyst recovery cost, metal residue and environmental pollution have hindered the wide industrial application of Suzuki reactions. In addition, heterogeneous catalysts have become important substitutes for homogeneous catalysts due to their recyclability. Many metal catalysts fixed on specific carriers, such as zeolites, silica, activated carbon, graphene, metal-organic frameworks and organic polymers, etc., perform well in Suzuki reactions. However, most of these carriers provide more active metal sites in powder form, and additional separation operations are required to recover the powder catalyst, which limits further practical applications.

[0006] Therefore, according to the above related technologies, it is urgent to develop a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by a membrane method. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to provide a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by membrane method, so as to solve the problems of low synthesis yield and difficult recovery of the catalyst in the prior art.

[0008] Based on the above purpose, the present invention provides a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by membrane method.

[0009] A green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by membrane method includes the following steps:

[0010] Step S1. Mix compound A with solvent A, stir evenly to obtain mixture A. Immerse the ceramic membrane in mixture A, take it out, wash it with solvent A, and then dry it to obtain a modified ceramic membrane.

[0011] Step S2. Mix palladium acetate and acetonitrile evenly to obtain a palladium acetate solution. Then immerse the modified ceramic membrane in the palladium acetate solution, take it out, wash it twice with acetonitrile, and then dry it at 43-47 °C to obtain a palladium-based catalytic membrane.

[0012] Step S3. Place the palladium-based catalytic membrane tube in a catalytic membrane tube reactor, and sequentially add 2-bromoaniline, 4-chlorophenylboronic acid, a base, and solvent B. Control the reaction temperature of the membrane reactor and react for 15 h, then cool to room temperature. Then use a peristaltic pump to pump out the reaction solution, and continue to wash out the residual reaction solution with ethanol. After low-pressure rotary evaporation and silica gel column purification, 4'-chloro-2-aminobiphenyl is obtained.

[0013] Preferably, in step S1, compound A is at least one of tannic acid, sodium alginate, chitosan, dopamine, and lignin.

[0014] Preferably, the dosage ratio of compound A to solvent A in step S1 is 2.5-6.5 g:1 L.

[0015] Solvent A is any one of deionized water, methanol, ethanol, and dichloromethane.

[0016] Preferably, the dosage ratio of compound A to solvent A in step S1 is 3-6 g:1 L.

[0017] Preferably, the drying temperature is 60 °C.

[0018] Preferably, in step S1, the impregnation temperature is 30-40 °C and the impregnation time is 5-12 h;

[0019] Preferably, in step S2, the impregnation temperature is 25-38 °C and the impregnation time is 10-14 h.

[0020] Preferably, the temperature during the impregnation in step S2 is 30°C and the impregnation time is 12 h.

[0021] Preferably, the dosage ratio of palladium acetate to acetonitrile in step S2 is 0.02 - 0.05 mol: 1 L.

[0022] Preferably, the dosage ratio of palladium acetate to acetonitrile in step S2 is 0.04 mol: 1 L;

[0023] Preferably, the solvent B in step S3 is at least one of ethanol, acetonitrile, toluene, water, trifluorotoluene, N,N-dimethylformamide.

[0024] Preferably, the base in step S3 is at least one of potassium carbonate, sodium carbonate, cesium carbonate, potassium phosphate, sodium phosphate, sodium hydroxide, potassium hydroxide, triethylamine.

[0025] Preferably, the dosage ratio of 2-bromoaniline, 4-chlorophenylboronic acid, base and solvent B in step S3 is 12 - 17 mmol: 16 - 26 mmol: 14 - 28 mmol: 150 - 200 mL.

[0026] Preferably, the dosage ratio of aryl halide, arylboronic acid, base and solvent B in step S3 is 15 mmol: 25 mmol: 20 mmol: 150 ml.

[0027] Preferably, the reaction temperature in step S3 is 50 - 65°C.

[0028] Advantages of the present invention:

[0029] The present invention provides a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by membrane method. Utilizing the self-polymerization mechanism of polymers, a ceramic membrane is modified, and palladium is loaded by impregnation method to prepare a palladium-based catalytic membrane. Since the polymer has polyhydroxy or amino functional groups, it can not only adhere to the ceramic matrix, but also provide a stable chemical environment for the metal. Common siloxane coupling agents as the heterogeneous catalysts prepared by connection lack intermolecular polymerization, and the ligand environment provided by siloxane coupling agents is often insufficient to stabilize metal ions. In contrast, the polymer adopted in the present invention exists widely in nature, has stronger adsorption capacity, and can load more metal. According to the advantages of the porous channels of the ceramic membrane, it promotes the contact between reaction substrates and active sites, enhancing the reaction effect. And the preparation process of this method is simple, the preparation environment is mild, and it can be produced on a large scale; and the present invention reacts in a membrane reactor, which can enhance the mass transfer and heat transfer performance. At the same time, the strong mass transfer effect in the membrane reactor enables the reaction liquid and the active components to be fully mixed, improving the reaction efficiency; meanwhile, the present invention uses a catalytic membrane to prepare 4'-chloro-2-aminobiphenyl by Suzuki-Miyaura coupling reaction, eliminating the cumbersome steps in traditional industries, avoiding the trouble of recovery compared with traditional heterogeneous catalysts, saving costs, greatly reducing the environmental harm, and having broad application prospects compared with the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only those of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0031] Figure 1 is an alumina ceramic membrane;

[0032] Figure 2 (a) is a palladium membrane modified by tannic acid, Figure 2 (b) is a palladium membrane modified by sodium alginate, Figure 2 (c) is a palladium membrane modified by chitosan, Figure 2 (d) is a palladium membrane modified by dopamine, Figure 2 (e) is a palladium membrane modified by lignin;

[0033] Figure 3 is a schematic diagram of the membrane reaction device;

[0034] Figure 4 is the chemical equation for preparing 4'-chloro-2-aminobiphenyl from 2-bromoaniline and 4-chlorophenylboronic acid;

[0035] Figure 5 is the hydrogen spectrum of 4'-chloro-2-aminobiphenyl;

[0036] Figure 6 The carbon spectrum of 4′-chloro-2-aminobiphenyl. Specific embodiments

[0037] To make the objectives, technical solutions and advantages of the present invention more clear and understandable, the following further details the present invention with reference to specific embodiments.

[0038] The sources and properties of some raw materials used in the present invention are as follows:

[0039] Tannic acid was purchased from Sangon Biotech (Shanghai) Co., Ltd.; sodium alginate was purchased from Shandong Yatu Biotechnology Co., Ltd.; chitosan was purchased from Shanghai Maokang Biotechnology Co., Ltd.; dopamine was purchased from Xi'an Pinjian Biotechnology Co., Ltd.; palladium acetate was purchased from Wuhan Qiongge Biotechnology Co., Ltd.; ceramic membrane was purchased from Nanjing Jiuwu Hi-Tech Co., Ltd.

[0040] Example 1: As shown in Figure 2 (a), a green preparation process for synthesizing 4′-chloro-2-aminobiphenyl by a tannic acid-modified palladium membrane method, comprising the following steps:

[0041] S1. Mix 0.6 g of tannic acid with 100 mL of deionized water, stir evenly to obtain a tannic acid solution, immerse a ceramic membrane (diameter 3 cm, length 8 cm, pore size 3 - 5 μm) in the tannic acid solution, with the immersion temperature at 30 °C and the immersion time at 5 h. After taking it out, wash it with deionized water and then dry it at 60 °C to obtain a modified ceramic membrane;

[0042] S2. Mix 0.004 mol of palladium acetate with 100 mL of acetonitrile evenly to obtain a palladium acetate solution, then immerse the modified ceramic membrane in the palladium acetate solution, with the immersion temperature at 30 °C and the immersion time at 10 h. After taking it out, wash it twice with acetonitrile and then dry it at 40 °C to obtain a palladium-based catalytic membrane;

[0043] S3. Place the palladium-based catalytic membrane in a catalytic membrane reactor, and sequentially add 12 mmol of 2-bromoaniline, 16 mmol of 4-chlorophenylboronic acid, 14 mmol of potassium carbonate and 150 mL of acetonitrile. Control the reaction temperature of the membrane reactor at 54 °C and react for 15 h, then cool to room temperature. Then use a peristaltic pump to pump out the reaction solution, and continue to wash out the residual reaction solution with ethanol. After low-pressure rotary evaporation and silica gel column purification, 4′-chloro-2-aminobiphenyl is obtained (yield 93.7%, purity 91.5%).

[0044] Example 2: As shown in Figure 2 (b), a green preparation process for synthesizing 4′-chloro-2-aminobiphenyl by a sodium alginate-modified palladium membrane method, comprising the following steps:

[0045] S1. Mix 0.5 g of sodium alginate with 100 mL of water, stir evenly to obtain an aqueous sodium alginate solution. Immerse a ceramic membrane (diameter 3 cm, length 8 cm, pore size 3 - 5 μm) in the aqueous sodium alginate solution at a temperature of 45 °C for 5.5 h. After taking it out, wash it with water and then dry it at 60 °C to obtain a modified ceramic membrane;

[0046] S2. Mix 0.004 mol of palladium acetate with 100 mL of acetonitrile evenly to obtain a palladium acetate solution. Then immerse the modified ceramic membrane in the palladium acetate solution at a temperature of 30 °C for 10 h. After taking it out, wash it twice with acetonitrile and then dry it at 40 °C to obtain a palladium-based catalytic membrane;

[0047] S3. Place the palladium-based catalytic membrane in a catalytic membrane reactor, and successively add 15 mmol of 2-bromoaniline, 25 mmol of 4-chlorophenylboronic acid, 20 mmol of cesium carbonate, and 150 mL of toluene. Control the reaction temperature of the membrane reactor at 60 °C and react for 15 h. After cooling to room temperature, pump out the reaction solution with a peristaltic pump, and continue to wash out the residual reaction solution with ethanol. Then perform low-pressure rotary evaporation and silica gel column purification to obtain 4′-chloro-2-aminobiphenyl (yield 90.5%, purity 96.3%).

[0048] Example 3: As Figure 2 (c) shows, a green preparation process for synthesizing 4′-chloro-2-aminobiphenyl by a chitosan-modified palladium membrane method, including the following steps:

[0049] S1. Mix 0.4 g of chitosan with 100 mL of water, stir evenly to obtain a chitosan solution. Immerse a ceramic membrane (diameter 3 cm, length 8 cm, pore size 3 - 5 μm) in the chitosan solution at a temperature of 37 °C for 6 h. After taking it out, wash it with water and then dry it at 60 °C to obtain a modified ceramic membrane;

[0050] S2. Mix 0.004 mol of palladium acetate with 100 mL of acetonitrile evenly to obtain a palladium acetate solution. Then immerse the modified ceramic membrane in the palladium acetate solution at a temperature of 30 °C for 12 h. After taking it out, wash it twice with acetonitrile and then dry it at 40 °C to obtain a palladium-based catalytic membrane;

[0051] S3. Place the palladium-based catalytic membrane in a catalytic membrane reactor, and successively add 15 mmol of 2-bromoaniline, 22.5 mmol of 4-chlorophenylboronic acid, 22.5 mmol of sodium phosphate, and

[0052] Example 4: As Figure 2 shown in (d), a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by dopamine-modified palladium membrane method, comprising the following steps:

[0053] S1. Mix 0.6 g of dopamine with 100 mL of water, stir evenly to obtain an aqueous dopamine solution. Immerse a ceramic membrane (diameter 3 cm, length 8 cm, pore size 3 - 5 μm) in the aqueous dopamine solution at a temperature of 37 °C for 4 h during immersion. After taking it out, wash it with water and then dry it at 60 °C to obtain a modified ceramic membrane;

[0054] S2. Mix 0.004 mol of palladium acetate with 100 mL of acetonitrile evenly to obtain a palladium acetate solution. Then immerse the modified ceramic membrane in the palladium acetate solution at a temperature of 30 °C for 12 h during immersion. After taking it out, wash it twice with acetonitrile and then dry it at 40 °C to obtain a palladium-based catalytic membrane;

[0055] S3. Place the palladium-based catalytic membrane in a catalytic membrane reactor, and successively add 15 mmol of 2-bromoaniline, 22.5 mmol of 4-chlorophenylboronic acid, 22.5 mmol of sodium phosphate, and 150 mL of N,N-dimethylformamide. Control the reaction temperature of the membrane reactor at 60 °C and react for 15 h, then cool to room temperature. Then pump out the reaction solution with a peristaltic pump, and continue to wash out the residual reaction solution with ethanol, followed by low-pressure rotary evaporation and silica gel column purification to obtain 4'-chloro-2-aminobiphenyl (yield 88.9%, purity 90.1%).

[0056] Example 5: As Figure 2 shown in (e), a green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by lignin-modified palladium membrane method, comprising the following steps:

[0057] S1. Mix 5.5 g of lignin with 100 mL of water, stir evenly to obtain an aqueous lignin solution. Immerse a ceramic membrane (diameter 3 cm, length 8 cm, pore size 3 - 5 μm) in the aqueous lignin solution at a temperature of 50 °C for 8.5 h during immersion. After taking it out, wash it with water and then dry it at 60 °C to obtain a modified ceramic membrane;

[0058] S2. Mix 0.004 mol of palladium acetate with 100 mL of acetonitrile evenly to obtain a palladium acetate solution. Then immerse the modified ceramic membrane in the palladium acetate solution at a temperature of 30 °C for 12 h during immersion. After taking it out, wash it twice with acetonitrile and then dry it at 40 °C to obtain a palladium-based catalytic membrane;

[0059] S3. Place the palladium-based catalytic membrane in a catalytic membrane reactor, and sequentially add 17 mmol of 2-bromoaniline, 26 mmol of 4-chlorophenylboronic acid, 28 mmol of sodium hydroxide, and 150 mL of methanol. Control the reaction temperature of the membrane reactor at 65 °C and react for 15 h. Then cool to room temperature, pump out the reaction solution using a peristaltic pump, and continue to wash out the residual reaction solution with ethanol. Perform low-pressure rotary evaporation and silica gel column purification to obtain 4′-chloro-2-aminobiphenyl (yield 92.6%, purity 93.3%).

[0060] Comparative Example 1:

[0061] This comparative example is the same as Example 1 except that the "modified ceramic membrane" is replaced with a "ceramic membrane", as Figure 1 shown, that is, step S1 is omitted, and the remaining steps and parameters are the same. This comparative example will not be repeated here. Finally, 4′-chloro-2-aminobiphenyl is obtained (yield 50.1%, purity 87.4%).

[0062] Comparative Example 2:

[0063] This comparative example is the same as Example 1 except that step S2 is deleted, and the remaining steps and parameters are the same. This comparative example will not be repeated here. Finally, 4′-chloro-2-aminobiphenyl cannot be obtained.

[0064] Comparative Example 3:

[0065] This comparative example is the same as Example 1 except that step S1 is modified as follows: Dissolve 0.6 g of 3-(2-aminoethylamino)propyltrimethoxysilane (KH792) in 100 mL of dichloromethane to obtain a silane coupling agent solution; immerse the ceramic membrane (diameter 3 cm, length 8 cm, pore size 3 - 5 μm) in it at a temperature of 30 °C for 1 h to obtain a modified ceramic membrane KH792-CM; wash twice with dichloromethane and dry at 40 °C. The remaining steps and parameters are the same. This comparative example will not be repeated here. Finally, 4′-chloro-2-aminobiphenyl is obtained (yield 82%, purity 87.5%).

[0066] Performance test:

[0067] Cyclic test:

[0068] First, use the membrane reaction device to perform a cyclic performance test on the membrane tube. After one reaction is completed, collect the reaction solution and wash the device with ethyl acetate, then the next reaction can be carried out. Evaluate the cyclic performance of the membrane tube through the yield of each cycle and the number of cycles. When the yield fluctuates and decreases by 10%, it will no longer be recorded. Thus, the number of recyclable times of Examples 1 - 5 of the present invention, and Comparative Example 3 are 25 times, 21 times, 26 times, 19 times, 23 times, and 7 times respectively.

[0069] Yield:

[0070] First, calculate the theoretical yield, which is the mass of the product assuming complete conversion of the reaction. Then, weigh the mass of the actually obtained 4'-chloro-2-aminobiphenyl prepared in Examples 1 - 6 and Comparative Examples 1 - 3 respectively.

[0071] Yield calculation formula:

[0072] Yield = (Actual yield / Theoretical yield) × 100%

[0073] Purity:

[0074] Accurately weigh 5 g of the 4'-chloro-2-aminobiphenyl prepared in Examples 1 - 6 and Comparative Examples 1 - 3 respectively, and dissolve it in dichloromethane. Prepare a series of standard solutions of 4'-chloro-2-aminobiphenyl with known concentrations, and analyze these solutions by HPLC to construct a standard curve. Then inject the 4'-chloro-2-aminobiphenyl solutions prepared in the to-be-tested Examples 1 - 6 and Comparative Examples 1 - 3 into the HPLC system for analysis, record the chromatogram of the to-be-tested acetylhydrazide and compare it with the standard curve, and calculate the concentrations of the 4'-chloro-2-aminobiphenyl prepared in Examples 1 - 6 and Comparative Examples 1 - 3 respectively.

[0075] Purity calculation formula:

[0076] Purity = (Actually measured concentration / Theoretical concentration) × 100%

[0077] Table 1

[0078] Item Yield / % Purity / % Example 1 86.7 91.5 Example 2 90.5 96.3 Example 3 84.2 92.4 Example 4 85.9 90.1 Example 5 87.3 94.5 Example 6 85.7 93.3 Comparative Example 1 50.1 87.4 Comparative Example 2 72.5 78.3 Comparative Example 3 68.7 82.5

[0079] Data analysis:

[0080] As can be seen from Table 1, the 4'-chloro-2-aminobiphenyl prepared by the present invention has higher yield and purity, which may be due to the fact that the present invention uses a polymer as a "bridge" between the ceramic membrane and the metal catalyst, and prepares a palladium-based catalytic membrane by impregnation, such as Figure 2 , Figure 3As shown, with the advantage of the multi-pores of the ceramic membrane itself, the active components can be well distributed on the surface and inside of the membrane, promoting the contact between the reaction substrate and the active sites, enhancing the reaction effect, and reacting in the membrane reactor can enhance the mass transfer and heat transfer performance. At the same time, the strong mass transfer effect in the membrane reactor allows the reaction liquid and the active components to be fully mixed, thereby improving the reaction efficiency. Among them, the modified ceramic membrane prepared using a variety of compounds improves the anti-poisoning ability and stability of the palladium-based catalytic membrane. At the same time, more active sites are introduced on the surface of the ceramic membrane, making the palladium-based catalytic membrane have higher catalytic activity, promoting the forward reaction, and improving the yield. It can also improve the utilization rate of palladium and reduce the amount of palladium used, thereby reducing the cost of the catalyst; in the Suzuki reaction carried out in the membrane reactor, under the action of the catalytic membrane, excess arylboronic acid and base can promote the complete reaction of aryl halide, thereby improving the yield and purity. Among them Figure 5 It is the hydrogen spectrum of 4'-chloro-2-aminobiphenyl; Figure 6 This is the carbon spectrum of 4'-chloro-2-aminobiphenyl, where the NMR data of 4'-chloro-2-aminobiphenyl are as follows:

[0081] Proton spectrum data: 1 H NMR (400MHz, CDCl3): δ7.44-7.41(m,4H),7.21-7.16(m,1H),7.11(dd,J=7.6,1. 6Hz, 1H), 6.85 (td, J=7.5, 1.2Hz, 1H), 6.78 (dd, J=8.0, 1.1Hz, 1H), 3.61 (s, 2H).

[0082] Carbon spectrum data: 13 C NMR (100MHz, CDCl3): δ143.52,138.02,133.22,130.59,130.46,129.60,129.12,128.96,126.43,118.91,116.78,115.86.GCMS(EI):calcd.for C12H10ClN203.05,found:203.01.

[0083] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0084] The present invention aims to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A green preparation process for synthesizing 4'-chloro-2-aminobiphenyl by membrane method, characterized in that, It includes the following steps: Step S1. Mix compound A with solvent A, stir evenly to obtain mixture A. Immerse the ceramic membrane in mixture A, take it out, wash it with solvent A, and then dry it to obtain a modified ceramic membrane; Step S2. Mix palladium acetate and acetonitrile evenly to obtain a palladium acetate solution. Then immerse the modified ceramic membrane in the palladium acetate solution, take it out, wash it twice with acetonitrile, and dry it to obtain a palladium-based catalytic membrane; Step S3. Place the palladium-based catalytic membrane in a catalytic membrane reactor, and sequentially add aryl halide, arylboronic acid, base, and solvent B. Control the reaction temperature of the membrane reactor and react for 15 h, then cool to room temperature. Then pump out the reaction solution using a peristaltic pump, and continue to wash out the residual reaction solution with ethanol. Perform low-pressure rotary evaporation and silica gel column purification to obtain 4'-chloro-2-aminobiphenyl; Compound A described in Step S1 is at least one of tannic acid, sodium alginate, chitosan, dopamine, and lignin.

2. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The dosage ratio of compound A to solvent A in Step S1 is 2.5 - 6.5 g:1 L; Solvent A is any one of deionized water, methanol, ethanol, and dichloromethane.

3. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The dosage ratio of compound A to solvent A in Step S1 is 3 - 6 g:1 L.

4. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The temperature during impregnation in Step S1 is 30 - 40 °C, and the impregnation time is 5 - 12 h; The temperature during impregnation in Step S2 is 23 - 38 °C, and the impregnation time is 10 - 14 h.

5. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The dosage ratio of palladium acetate to acetonitrile in Step S2 is 0.02 - 0.05 mol:1 L.

6. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The dosage ratio of palladium acetate to acetonitrile in Step S2 is 0.04 mol:1 L; Solvent B described in Step S3 is at least one of ethanol, acetonitrile, toluene, water, trifluorotoluene, and N,N-dimethylformamide.

7. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The base described in Step S3 is at least one of potassium carbonate, sodium carbonate, cesium carbonate, potassium phosphate, sodium phosphate, sodium hydroxide, potassium hydroxide, and triethylamine.

8. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The dosage ratio of aryl halide, arylboronic acid, base, and solvent B in Step S3 is 12 - 17 mmol:16 - 26 mmol:14 - 28 mmol:150 - 200 mL.

9. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, wherein, The dosage ratio of aryl halide, arylboronic acid, base, and solvent B in Step S3 is 15 mmol:25 mmol:20 mmol:150 ml.

10. The green preparation process of synthesizing 4'-chloro-2-aminobiphenyl by membrane method according to claim 1, characterized in that, The reaction temperature in Step S3 is 50 - 65 °C.

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