阅读说明：本技术 一种采用微通道反应器合成联苯类化合物的方法 (Method for synthesizing biphenyl compounds by adopting microchannel reactor ) 是由 吴范宏 叶斌斌 吴晶晶 吴卓 宋亚龙 张兰玲 陈盼盼 胡婕颖 于 2021-08-17 设计创作，主要内容包括：本发明涉及一种采用微通道反应器合成联苯类化合物的方法,包括将式(1)所示的化合物、式(2)所示的化合物、式(3)所示的化合物和铜催化剂在微通道反应器中混合,并进行重氮化偶合反应,再将所得反应产物进行纯化即得式(4)所示的化合物。与现有技术相比,本发明采用微通道反应器有效减少了重氮化偶合反应的时间,增加了反应的稳定性和效率,提高了反应收率和纯度,环保安全,工艺简洁,成本降低,具有连续化工业生产的优点具有等优点。(The invention relates to a method for synthesizing biphenyl compounds by adopting a microchannel reactor, which comprises the steps of mixing a compound shown in a formula (1), a compound shown in a formula (2), a compound shown in a formula (3) and a copper catalyst in the microchannel reactor, carrying out diazotization coupling reaction, and purifying the obtained reaction product to obtain a compound shown in a formula (4). Compared with the prior art, the method has the advantages of effectively reducing the time of diazotization coupling reaction by adopting the microchannel reactor, increasing the stability and efficiency of the reaction, improving the reaction yield and purity, protecting environment, ensuring safety, simplifying the process, reducing the cost, having the advantages of continuous industrial production and the like.)

1. A method for synthesizing biphenyl compounds by adopting a microchannel reactor is characterized by comprising the following steps:

s1, mixing the compound shown in the formula (1), the compound shown in the formula (2), the compound shown in the formula (3) and a copper catalyst in a microchannel reactor, and performing diazotization coupling reaction according to the following formula to obtain a reaction crude product;

s2, purifying the reaction product obtained in the step (1) to obtain a compound shown in a formula (4);

wherein:

r1, R2, R3, R4 and R5 are all selected from one or more of hydrogen, fluorine, bromine, chlorine, trifluoromethyl, trifluoromethoxy, methoxy and methyl;

r6 is selected from one or more of methyl, ethyl, propyl, butyl, amyl, isopropyl, isobutyl and isoamyl;

r7 is selected from one or more of hydrogen, dimethylamino, diethylamino, dipropylamino, diisopropylamino and hydroxyl.

2. The method for synthesizing biphenyl compounds according to claim 1, wherein the molar ratio of the compound represented by formula (1), the compound represented by formula (2), the compound represented by formula (3) and the copper catalyst in S1 is: 1 (1.05-1.8), (1.05-1.5) and (0.1-0.5).

3. The method for synthesizing biphenyl compounds according to claim 1, wherein the compounds are dissolved in S1 by three solvents, and then mixed with the copper catalyst in the microchannel reactor.

4. The method for synthesizing biphenyl compounds according to claim 3, wherein in S1:

the solvent used by the compound shown in the formula (1), (2) and (3) is one or more selected from tetrahydrofuran, tert-butyl methyl ether, dichloromethane, isopropyl acetate, acetonitrile and dichloroethane;

the copper catalyst is one or the combination of more of cuprous chloride, cuprous bromide and cuprous iodide.

5. The method for synthesizing biphenyl compounds by using the microchannel reactor as claimed in claim 1, wherein the microchannel reactor in S1 comprises a first raw material storage tank, a second raw material storage tank, a product collecting bottle, three to ten reaction modules;

the first raw material storage tank and the second raw material storage tank are connected with the first microchannel reaction module, and the first microchannel reaction module is sequentially connected with other microchannel reaction modules and the product collecting bottle in series;

the material flows from the first reaction module to the last reaction module.

6. The method for synthesizing biphenyl compounds according to claim 1, wherein the microchannel reactor of S1 is a pipe reactor or a core reactor.

7. The method for synthesizing biphenyl compounds according to claim 1, wherein in S1:

the mass concentration of the compound represented by the formula (1) is 10-20%, the mass concentration of the compound represented by the formula (2) is 15-25%, the mass concentration of the compound represented by the formula (3) is 10-20%, the mass concentration of the copper catalyst is 1-5%, and the balance is a solvent.

8. The method for synthesizing biphenyl compounds according to claim 1, wherein the reaction residence time of the reactants and the copper catalyst in the microchannel is 20s to 150 s.

9. The method for synthesizing biphenyl compounds by using the microchannel reactor as claimed in claim 1, wherein the reaction temperature of each reaction module in the microchannel reactor is set to 6-50 ℃;

the pressure in the microchannel reactor is 5 bar-8 bar.

10. The method for synthesizing biphenyl compounds according to claim 1, wherein the solvent used in the purification process of S2 is one or more selected from petroleum ether, toluene, n-hexane, and n-heptane.

Technical Field

The invention relates to the field of organic synthesis, in particular to a method for synthesizing biphenyl compounds by adopting a microchannel reactor.

Background

Biphenyl compounds are important organic raw materials and are widely applied to the fields of medicines, pesticides, dyes, liquid crystal materials and the like. It is usually an important intermediate of anti-inflammatory drugs, such as flurbiprofen (non-steroidal anti-inflammatory drug), which is suitable for rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, etc., and bifendate (bifendatum) is a commonly used drug for treating viral hepatitis and transaminase increase caused by drug-induced liver injury. The invention develops a method for synthesizing biphenyl compounds by using a microchannel reactor, and has wide application prospect.

Batch kettles are generally adopted industrially for mass production, wherein the traditional kettle-type diazotization process has certain dangerousness, and the prior art has the technical bottlenecks of more rigorous reaction conditions, longer reaction time, higher cost, low purity and partial environmental pollution.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a method for synthesizing biphenyl compounds by using a microchannel reactor, which has the advantages of milder conditions, shorter reaction time, lower cost, higher purity and more environment-friendly property, so as to overcome the defects of the prior art.

The purpose of the invention can be realized by the following technical scheme:

the invention aims to protect a method for synthesizing biphenyl compounds by adopting a microchannel reactor, which comprises the following steps:

s1, mixing the compound shown in the formula (1), the compound shown in the formula (2), the compound shown in the formula (3) and a copper catalyst in a microchannel reactor, and performing diazotization coupling reaction according to the following formula to obtain a reaction crude product;

s2, purifying the reaction product obtained in the step (1) to obtain a compound shown in a formula (4);

wherein:

r1, R2, R3, R4 and R5 are all selected from one or more of hydrogen, fluorine, bromine, chlorine, trifluoromethyl, trifluoromethoxy, methoxy and methyl;

r6 is selected from one or more of methyl, ethyl, propyl, butyl, amyl, isopropyl, isobutyl and isoamyl;

r7 is selected from one or more of hydrogen, dimethylamino, diethylamino, dipropylamino, diisopropylamino and hydroxyl.

Further, the molar ratio of the compound represented by formula (1), the compound represented by formula (2), the compound represented by formula (3) and the copper catalyst in S1 is: 1 (1.05-1.8), (1.05-1.5), (0.1-0.5), preferably 1 (1.05-1.5), (1.05-1.2), (0.1-0.3).

Further, in S1, each compound was dissolved by three solvents, respectively, and then mixed together with the copper catalyst in the microchannel reactor.

Further, in S1:

the solvent used by the compound shown in the formula (1), (2) and (3) is one or more selected from tetrahydrofuran, tert-butyl methyl ether, dichloromethane, isopropyl acetate, acetonitrile and dichloroethane;

the copper catalyst is one or the combination of more of cuprous chloride, cuprous bromide and cuprous iodide.

Further, the microchannel reactor in S1 includes a first raw material storage tank, a second raw material storage tank, a product collection bottle, and three to ten reaction modules, preferably 3 to 5;

the first raw material storage tank and the second raw material storage tank are connected with the first microchannel reaction module, and the first microchannel reaction module is sequentially connected with other microchannel reaction modules and the product collecting bottle in series;

the material flows from the first reaction module to the last reaction module.

Further, the microchannel reactor in S1 is a pipe reactor or a core reactor.

Furthermore, the material of the microchannel reactor is special glass or special silicon carbide.

Further, in S1:

the mass concentration of the compound represented by the formula (1) is 10 to 20%, preferably 10 to 15%, the mass concentration of the compound represented by the formula (2) is 15 to 25%, the mass concentration of the compound represented by the formula (3) is 10 to 20%, preferably 10 to 15%, the mass concentration of the copper catalyst is 1 to 5%, preferably 1 to 3%, and the balance is a solvent.

Further, the flow rate of the solution of the compound shown in the formula (1) in the microchannel is 20 mL/min-50 mL/min, and the flow rate of the solution of the compound shown in the formula (2) in the microchannel is 10 mL/min-40 mL/min; the flow rate of the solution of the compound represented by the formula (3) in the microchannel is 20mL/min to 50 mL/min.

Further, the reaction residence time of the reactants in the microchannel is 20s to 150s, preferably 40s to 110 s.

Further, the reaction temperature of each reaction module in the microchannel reactor is set to be 6-50 ℃;

the pressure in the microchannel reactor is 5 bar-8 bar.

Further, the solvent used in the purification treatment in S2 is one or a combination of more of petroleum ether, toluene, n-hexane, and n-heptane, preferably petroleum ether or n-heptane.

Compared with the prior art, the invention has the following technical advantages:

1) the invention provides a method for synthesizing biphenyl compounds through a continuous flow microchannel reactor. The microchannel reactor has the characteristics of quick reaction, separation and analysis compared with a kettle type reactor.

2) According to the technical scheme, the reaction can be continuously carried out through the continuous flow microchannel reactor, the reaction time is shortened, the reaction efficiency and the safety are obviously improved, the advantages of seamless amplification and the like are achieved, and the method is more suitable for large-scale industrial production.

Drawings

Fig. 1 is a schematic flow chart of a process for synthesizing biphenyl compounds by using a microchannel reactor in the technical scheme.

Detailed Description

The synthesis process of the invention is as follows:

s1, mixing the compound shown in the formula (1), the compound shown in the formula (2), the compound shown in the formula (3) and a copper catalyst in a microchannel reactor, referring to the figure 1, and performing diazotization coupling reaction according to the following formula to obtain a reaction crude product;

s2, purifying the reaction product obtained in the step (1) to obtain a compound shown in a formula (4);

wherein: r1, R2, R3, R4 and R5 are all selected from one or more of hydrogen, fluorine, bromine, chlorine, trifluoromethyl, trifluoromethoxy, methoxy and methyl; r6 is selected from one or more of methyl, ethyl, propyl, butyl, amyl, isopropyl, isobutyl and isoamyl; r7 is selected from one or more of hydrogen, dimethylamino, diethylamino, dipropylamino, diisopropylamino and hydroxyl.

The molar ratio of the compound represented by the formula (1), the compound represented by the formula (2), the compound represented by the formula (3) and the copper catalyst is: 1 (1.05-1.8), (1.05-1.5), (0.1-0.5), preferably 1 (1.05-1.5), (1.05-1.2), (0.1-0.3). Each compound was first dissolved by three solvents separately and then mixed with the copper catalyst in a microchannel reactor. The solvent used by the compound shown in the formula (1), (2) and (3) is one or more selected from tetrahydrofuran, tert-butyl methyl ether, dichloromethane, isopropyl acetate, acetonitrile and dichloroethane; the copper catalyst is one or more of cuprous chloride, cuprous bromide and cuprous iodide.

The microchannel reactor comprises a first raw material storage tank, a second raw material storage tank, a product collecting bottle and three to ten reaction modules, and preferably 3 to 5 reaction modules, as shown in fig. 1; the first raw material storage tank and the second raw material storage tank are connected with the first microchannel reaction module, and the first microchannel reaction module is sequentially connected with other microchannel reaction modules and the product collecting bottle in series; the material flows from the first reaction module to the last reaction module. The microchannel reactor is a pipeline reactor or a core-type structure reactor. When the material is selected specifically, the material of the microchannel reactor is special glass or special silicon carbide.

The mass concentration of the compound represented by the formula (1) is 10 to 20%, preferably 10 to 15%, the mass concentration of the compound represented by the formula (2) is 15 to 25%, the mass concentration of the compound represented by the formula (3) is 10 to 20%, preferably 10 to 15%, the mass concentration of the copper catalyst is 1 to 5%, preferably 1 to 3%, and the balance is a solvent. The flow rate of the solution of the compound shown in the formula (1) in the microchannel is 20-50 mL/min, and the flow rate of the solution of the compound shown in the formula (2) in the microchannel is 10-40 mL/min; the flow rate of the solution of the compound represented by the formula (3) in the microchannel is 20mL/min to 50 mL/min.

The invention discloses a method for synthesizing biphenyl compounds by adopting a microchannel reactor, which has a full-continuous integrated system for continuous synthesis, continuous separation and on-line analysis. The annual flux of the micro-channel reactor system is about 80 tons at most, the temperature range is-60-200 ℃, and the pressure range is as follows: 0-18 bar, a Teflon pump can be arranged, the reactor is made of special glass or special silicon carbide, and the heat exchange medium is heat conduction oil.

The invention is described in detail below with reference to the figures and specific embodiments.

Example 1

(1) Dissolving 2, 4-difluoroaniline, benzene and cuprous chloride in tetrahydrofuran under stirring to obtain a mixed solution with the mass fraction of 15%, wherein the flow rate is 25 ml/min; dissolving methyl nitrite in tetrahydrofuran to obtain a solution with the mass fraction of 20%, wherein the flow rate is 15 ml/min; setting the reaction temperature of the microchannel reactor system to be 20 ℃, setting the pressure to be 5bar, setting the reaction residence time to be 100s, pumping the 2 solutions into the microchannel reactor through a metering pump, enabling the solutions to flow through 3 modules, and enabling the products to flow out from an outlet of the reactor after the reaction is finished to obtain 34g of reaction products;

(2) filtering CuCl from the 34g of reaction product, washing once with 30mL of dilute hydrochloric acid aqueous solution, washing once with 30mL of saturated sodium chloride solution, separating to obtain an organic layer, recovering the solvent, cooling and crystallizing to obtain 7.1g of a crude product, adding 1mL of petroleum ether under the ice bath condition, stirring for 1h, and filtering to obtain 4.7g of 2, 4-difluorobiphenyl (the yield is 80.2%, and the purity is 99.3%).

Product characterization data were as follows:

¹H NMR(500MHz，DMSO-d6):δ7.48-7.41(m,8H)。

¹³C NMR(125MHz,DMSO-d6):δ166.06(dd,^1”J_C-F＝246.3,13.75)，δ161.53(dd,^1”J_C-F＝248.8,12.5)，136.21(d,J＝5.5Hz)，129.55(d,J＝8.8Hz)，129.22，129.17，128.10，124.87，113.49，104.73。

example 2

(1) Dissolving 4-bromo-2-fluoroaniline, benzene and cuprous chloride in tetrahydrofuran under stirring to obtain a mixed solution with the mass fraction of 15%, wherein the flow rate is 25 ml/min; dissolving isobutyl nitrite in tetrahydrofuran to obtain a solution with the mass fraction of 20%, wherein the flow rate is 15 ml/min; setting the reaction temperature of the microchannel reactor system to be 20 ℃, setting the pressure to be 5bar, setting the reaction residence time to be 100s, pumping the 2 solutions into the microchannel reactor through a metering pump, enabling the solutions to flow through 3 modules, and enabling the products to flow out from an outlet of the reactor after the reaction is finished to obtain 35g of reaction products;

(2) filtering CuCl from the 35g of reaction product, washing once with 30mL of dilute hydrochloric acid aqueous solution, washing once with 30mL of saturated sodium chloride solution, separating to obtain an organic layer, recovering the solvent, cooling and crystallizing to obtain 7.5g of a crude product, adding 1mL of petroleum ether under the ice bath condition, stirring for 1h, and filtering to obtain 5g of 4-bromo-2-fluorobiphenyl (yield 80.2%, purity 99.1%).

Product characterization data were as follows:

¹H NMR(500MHz，DMSO-d6):δ7.46-7.38(m,8H).

¹³C NMR(125MHz,DMSO-d6):δ159.43(d,¹J_C-F＝248.8Hz)，136.21(d,³J_C-F＝6.3Hz)，129.21，129.19，129.16，128.10，126.61(d,²J_C-F＝13.75Hz)，125.72(d,⁴J_C-F＝3.75Hz)，121.15(d,³J_C-F＝13.75Hz,8.75)，118.84(d,²J_C-F＝6.3Hz)。

example 3

This example and example 2 were conducted at a reaction temperature of 40 ℃ in a microchannel reactor system other than in step (1) of this example, to give 5.05g of 4-bromo-2-fluorobiphenyl (yield 81%, purity 99.3%).

Example 4

This example and example 2 were conducted at a reaction temperature which was set to 50 ℃ in a different microchannel reactor system from that in the step (1) of this example, to give 4.7g of 4-bromo-2-fluorobiphenyl (yield 76%, purity 99.2%).

Example 5

This example was different from example 2 in that the pressure in the microchannel reactor system in step (1) of this example was set to 8bar, and 5.1g of 4-bromo-2-fluorobiphenyl was obtained (yield 82%, purity 99.4%).

Example 6

This example is different from example 2 in that cuprous bromide was used as a copper catalyst in step (1) of this example, and 4.85g of 4-bromo-2-fluorobiphenyl was obtained (yield 78%, purity 99.0%).

Example 7

This example differs from example 2 in that the flow rate of the 4-bromo-2-fluoroaniline solution in step (1) in this example was 35ml/min and the flow rate of the isobutyl nitrite solution was 25ml/min, to give 4.67g of 4-bromo-2-fluorobiphenyl (yield 75%, purity 99.5%).

Example 8

This example differs from example 2 in that the residence time in step (1) of this example is 50s, giving 4.36g of 4-bromo-2-fluorobiphenyl (yield 70%, purity 99.1%).

Example 9

This example and example 2 different from this example in step (2), the solvent used was n-heptane, to give 5.17g (yield 83%, purity 99.7%) of 4-bromo-2-fluorobiphenyl.

The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.