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CN111072697A - Preparation method of 4-phenoxyphenylboronic acid - Google Patents

Preparation method of 4-phenoxyphenylboronic acid Download PDF

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CN111072697A
CN111072697A CN201911381679.2A CN201911381679A CN111072697A CN 111072697 A CN111072697 A CN 111072697A CN 201911381679 A CN201911381679 A CN 201911381679A CN 111072697 A CN111072697 A CN 111072697A
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phenoxyphenylboronic
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CN111072697B (en
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张进
冷延国
常志亮
冯学民
孟庆斌
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CANGZHOU PURUI DONGFANG SCIENCE & TECHNOLOGY CO LTD
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    • C07ORGANIC CHEMISTRY
    • C07FACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F5/00Compounds containing elements of Groups 3 or 13 of the Periodic Table
    • C07F5/02Boron compounds
    • C07F5/025Boronic and borinic acid compounds

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Abstract

The invention discloses a preparation method of 4-phenoxy phenylboronic acid, and belongs to the technical field of organic boric acid chemistry. Starting from diphenyl ether, reacting with NBS to generate 4,4' -dibromodiphenyl ether, then reacting with boric acid ester and butyl lithium in one pot, and hydrolyzing to obtain 4-phenoxy phenylboronic acid. In the invention, dibromo-compound which is easy to purify is generated during bromination, and mono-substituted product is generated by controlling the consumption of lithiation reagent and boric acid ester during lithiation.

Description

Preparation method of 4-phenoxyphenylboronic acid
Technical Field
The invention relates to preparation of a medical intermediate organic boric acid, in particular to a preparation method of 4-phenoxyphenylboronic acid, belonging to the technical field of organic synthesis.
Background
4-phenoxyphenylboronic acid, white powdery or crystalline solid, CAS: 51067-38-0, is mainly used for synthesis of BTK target innovation drugs, tinib. Such as Evobrutinib, currently in the third clinical stage, is indicated for systemic lupus erythematosus, multiple sclerosis and rheumatoid arthritis. Tirabrutinib, currently filed for NDA, is indicated for lymphoma. Ibrutinib, currently approved for marketing, is indicated in mantle cell lymphoma, small lymphocytic lymphoma, chronic lymphocytic leukemia, graft versus host disease, waldenstrom macroglobulinemia, and marginal zone lymphoma. From the above, it can be seen that the boric acid is a very important product of organoboronic acids, and the current synthetic routes mainly include the following three types:
the literature reports that 4-bromodiphenyl ether and magnesium metal are adopted to form a Grignard reagent, then the Grignard reagent reacts with trimethyl borate at low temperature, and acid is added for hydrolysis to obtain 4-phenoxyphenylboronic acid with the yield of 93%. Chem,2012, vol.10, #33,6693 and 6704.
The second document reports that 4-bromodiphenyl ether is reacted with n-butyllithium, then reacted with triisopropyl borate at low temperature, and hydrolyzed with acid to obtain 4-phenoxyphenylboronic acid with a yield of 84% by adopting a continuous flow reaction mode. Refer to org.ProcesssDev, 2018, vol.22, #6, 741-746.
The third report of the document reports that diphenyl ether and boron trichloride are reacted at high temperature under the catalysis of metal aluminum, methyl iodide and the like, and then hydrolyzed to obtain 4-phenoxyphenylboronic acid, and the yield of the first step of the method is only 4%, so that the method is only suitable for quickly preparing samples and is not suitable for being used as a process of the method. Reference is made to J.Am.chem.Soc,1960, vol.82, 4163-4166.
From the above methods, except that the third method is not suitable for process amplification, the former two methods have high yield of boric acid after 4-phenoxybromobenzene forms active species and reacts with boric acid ester.
In the existing 4-phenoxybromobenzene raw material synthesis method, except for adopting 4-bromophenol to react with iodobenzene, the yield of the reaction with bromobenzene is not high, and the most effective, economical and effective mode is to adopt diphenyl ether to react with NBS to generate 4-phenoxybromobenzene. Therefore, there is a need for an improvement of the existing synthesis method to meet the need of industrial scale-up and to meet the high purity product supply in the market.
Disclosure of Invention
In order to overcome the technical defects, the invention discloses a preparation method of 4-phenoxyphenylboronic acid. Starting from diphenyl ether, reacting with a brominating reagent to generate 4,4' -dibromodiphenyl ether, then reacting with boric acid ester and butyl lithium, and hydrolyzing to obtain 4-phenoxy phenylboronic acid. In the invention, a dibromo-compound which is easy to purify is generated during bromination, and a mono-substituted product is generated by controlling the dosage of a lithiation reagent and boric acid ester during lithiation.
The invention relates to a preparation method of 4-phenoxyphenylboronic acid, which comprises the following steps:
reacting diphenyl ether with a brominating reagent to generate 4,4' -dibromo diphenyl ether, reacting the intermediate with boric acid ester and n-butyl lithium, and hydrolyzing and purifying to obtain the 4-phenoxy phenylboronic acid.
The reaction equation is expressed as:
Figure BDA0002342428020000031
further, in the technical scheme, NBS and bromine are adopted as the brominating reagent, wherein when the bromine reacts, the reaction can be accelerated in the presence of Lewis acid and sodium bromate. From an industrial scale-up perspective, NBS brominating reagents are preferred.
Further, in the above technical scheme, the bromination reaction can be realized in common organic solvents. Preferred reaction solvents are common solvents such as tetrahydrofuran, water, methanol, ethanol, dichloromethane, 1, 2-dichloroethane, acetonitrile, acetone, ethyl acetate, and the like.
Further, in the above technical scheme, the molar ratio of the brominating agent to the diphenyl ether during the bromination reaction is 2-3:1, and the preferred equivalent ratio is 2.2: 1.
Further, in the above technical scheme, the reaction temperature is-10 ℃ to 50 ℃ during the bromination reaction.
In the actual reaction, after the bromination reaction treatment, the purity of the obtained crude product can reach about 99.0 percent, and after one-time pulping and purification, the purity can reach more than 99.8 percent.
Further, in the above technical scheme, the 4,4 '-dibromodiphenyl ether, the borate and the n-butyllithium are preferably carried out under one-pot conditions, that is, a mode of mixing the 4,4' -dibromodiphenyl ether and the borate in a solvent and dropwise adding the n-butyllithium.
Further, in the above technical solution, the borate is selected from trimethyl borate, triethyl borate, triisopropyl borate and n-butyl borate, and preferably triisopropyl borate.
Furthermore, in the technical scheme, the equivalent ratio of the 4,4' -dibromodiphenyl ether, the boric acid ester and the n-butyllithium is 1:1-1.1: 2-2.5.
Further, in the technical scheme, when the method is reacted with n-butyl lithium in a one-pot method, the reaction temperature is controlled to be-40 ℃ to-10 ℃.
Further, in the above technical scheme, when reacting with n-butyllithium in one pot, the reaction solvent is one or more selected from tetrahydrofuran, 2-methyltetrahydrofuran, diethoxymethane, cyclopentylmethyl ether, tert-butylmethyl ether and the like, or a mixture of the above solvent and toluene.
Advantageous effects of the invention
In the invention, two sides of diphenyl ether are brominated simultaneously to generate symmetrical di-p-bromophenyl ether, the intermediate is easy to purify, and the mono-substituted product is generated only by controlling the dosage of a lithiation reagent and boric acid ester during lithiation.
The method overcomes the defects that when the 4-phenoxybromobenzene needs to be purified in the prior art, the boiling point is too high during direct rectification, heat conduction oil needs to be rectified at high temperature, and when recrystallization purification is adopted, multiple crystallization is needed, the process is complicated, and the recovery rate is not high.
The method has been verified on a hundred kilogram scale and has the prospect of an industrial method.
Detailed Description
Example 1
Diphenyl ether (17.2g,0.1mol) was dissolved in 140mL of dichloroethane, NBS (39.2g, 0.22mol) was added portionwise with stirring, after the addition was complete, the mixture was stirred at room temperature for 1 hour, then heated to reflux overnight, HPLC showed complete reaction, the temperature was reduced to below 35 ℃, and the solvent was evaporated off under reduced pressure. Pouring the system into ice water, stirring vigorously for half an hour, adding ethyl acetate for extraction twice, evaporating the solvent by rotation, and recrystallizing the crude product by using an ethanol/toluene (1/5) mixed solvent to obtain 31.2 g of off-white solid 4,4' -dibromodiphenyl ether with the purity of 99.8 percent and the yield of 95.0 percent.
Under nitrogen, the above 4,4' -dibromodiphenyl ether (16.4g,0.05mol), diethoxymethane (160mL) and triisopropyl borate (9.4g,0.05mol) were mixed, cooled to-70 ℃ to-60 ℃, and 40mL of a 2.5M n-butyllithium hexane solution was added dropwise. After the dropwise addition, stirring was carried out for 1 hour under heat preservation. Then naturally raising the temperature to room temperature for reaction overnight, cooling and adding 1M hydrochloric acid for quenching, wherein the temperature is not higher than 0 ℃ in the quenching process. Diethoxyhexane (60mL) was extracted twice, the oil layers were combined, evaporated to dryness under reduced pressure, added with ethyl acetate to redissolve, filtered and evaporated to dryness again, and n-heptane was slurried to give an off-white solid 8.2 g, yield 77%, HPLC: 99.8%, HNMR structure.
Example 2
Diphenyl ether (17.2g,0.1mol) was dissolved in 80mL dioxane, NBS (39.2g, 0.22mol) was added portionwise with stirring, and after the addition was complete, the mixture was stirred at room temperature for 1 hour, then heated to 50 ℃ for 3 hours, HPLC showed completion, and the solvent was evaporated off under reduced pressure. Pouring the system into ice water, stirring vigorously for half an hour, adding ethyl acetate for extraction, evaporating the solvent to dryness by rotation, and recrystallizing the crude product by using an ethanol/toluene (1/5) mixed solvent to obtain 30.6 g of off-white solid 4,4' -dibromodiphenyl ether with the purity of 99.7 percent and the yield of 93.3 percent.
Under nitrogen, the above 4,4' -dibromodiphenyl ether (16.4g,0.05mol), diethoxymethane (160mL) and triisopropyl borate (9.4g,0.05mol) were mixed, cooled to-70 ℃ to-60 ℃, and 40mL of a 2.5M n-butyllithium hexane solution was added dropwise. After the dropwise addition, stirring was carried out for 1 hour under heat preservation. Then naturally raising the temperature to room temperature for reaction overnight, cooling and adding 1M hydrochloric acid for quenching, wherein the temperature is not higher than 0 ℃ in the quenching process. Diethoxyhexane (60mL) was extracted twice, the oil layers were combined, evaporated to dryness under reduced pressure, added with ethyl acetate to redissolve, filtered and evaporated to dryness again, and n-heptane was slurried to give an off-white solid 8.2 g, yield 77%, HPLC: 99.8%, HNMR structure.
Example 3
Diphenyl ether (17.2g,0.1mol) was dissolved in 120mL acetonitrile, NBS (39.2g, 0.22mol) was added portionwise with stirring, and after completion of the addition, the mixture was stirred at room temperature for 1 hour, then heated to 50 ℃ to react for 3 hours, HPLC showed completion of the reaction, and then the solvent was distilled off under reduced pressure. Pouring the system into ice water, stirring vigorously for half an hour, adding ethyl acetate for extraction, evaporating the solvent to dryness by rotation, and recrystallizing the crude product by using an ethanol/toluene (1/5) mixed solvent to obtain 30.9 g of off-white solid 4,4' -dibromodiphenyl ether with the purity of 99.7 percent and the yield of 94.1 percent.
The above 4,4' -dibromodiphenyl ether (16.4g,0.05mol), tetrahydrofuran (160mL) and triisopropyl borate (9.4g,0.05mol) were mixed under nitrogen atmosphere, cooled to-70 ℃ to-60 ℃ and 40mL of a 2.5M n-butyllithium hexane solution was added dropwise. After the dropwise addition, stirring was carried out for 1 hour under heat preservation. Then naturally raising the temperature to room temperature for reaction overnight, cooling and adding 1M hydrochloric acid for quenching, wherein the temperature is not higher than 0 ℃ in the quenching process. Tetrahydrofuran (60mL) was extracted twice, the oil layers were combined, evaporated to dryness under reduced pressure, added ethyl acetate to redissolve, filtered and evaporated again to dryness, and n-heptane/methyl tert-butyl ether (10/1) slurried to give 7.9 g of an off-white solid with a yield of 74%, HPLC: 99.9%, and the HNMR structure is consistent.
Example 4
Diphenyl ether (17.2g,0.1mol) was dissolved in 120mL acetonitrile, NBS (39.2g, 0.22mol) was added portionwise with stirring, and after completion of the addition, the mixture was stirred at room temperature for 1 hour, then heated to 50 ℃ to react for 3 hours, HPLC showed completion of the reaction, and then the solvent was distilled off under reduced pressure. Pouring the system into ice water, stirring vigorously for half an hour, adding ethyl acetate for extraction, evaporating the solvent to dryness by rotation, and recrystallizing the crude product by using an ethanol/toluene (1/5) mixed solvent to obtain 30.9 g of off-white solid 4,4' -dibromodiphenyl ether with the purity of 99.7 percent and the yield of 94.1 percent.
The above 4,4' -dibromodiphenyl ether (16.4g,0.05mol), tetrahydrofuran (160mL) and triisopropyl borate (10.3g,0.055mol) were mixed under nitrogen, cooled to-70 ℃ to-60 ℃, and 44mL of a 2.5M n-butyllithium hexane solution was added dropwise. After the dropwise addition, stirring was carried out for 1 hour under heat preservation. Then naturally raising the temperature to room temperature for reaction overnight, cooling and adding 1M hydrochloric acid for quenching, wherein the temperature is not higher than 0 ℃ in the quenching process. Tetrahydrofuran (60mL) was extracted twice, the oil layers were combined, evaporated to dryness under reduced pressure, added ethyl acetate to redissolve, filtered and evaporated again to dryness, and n-heptane/methyl tert-butyl ether (10/1) slurried to give 9.7 g of an off-white solid in 91% yield, HPLC: 99.9%, and the HNMR structure is consistent.
Example 5
Diphenyl ether (17.2g,0.1mol) was dissolved in 120mL acetonitrile, NBS (39.2g, 0.22mol) was added portionwise with stirring, and after completion of the addition, the mixture was stirred at room temperature for 1 hour, then heated to 50 ℃ to react for 3 hours, HPLC showed completion of the reaction, and then the solvent was distilled off under reduced pressure. Pouring the system into ice water, stirring vigorously for half an hour, adding ethyl acetate for extraction, evaporating the solvent to dryness by rotation, and recrystallizing the crude product by using an ethanol/toluene (1/5) mixed solvent to obtain 30.9 g of off-white solid 4,4' -dibromodiphenyl ether with the purity of 99.7 percent and the yield of 94.1 percent.
The above 4,4' -dibromodiphenyl ether (16.4g,0.05mol), 2-methyltetrahydrofuran (160mL) and triisopropyl borate (10.3g,0.055mol) were mixed under nitrogen, cooled to-70 ℃ to-60 ℃, and 44mL of a 2.5M n-butyllithium hexane solution was started dropwise. After the dropwise addition, stirring was carried out for 1 hour under heat preservation. Then naturally raising the temperature to room temperature for reaction overnight, cooling and adding 1M hydrochloric acid for quenching, wherein the temperature is not higher than 0 ℃ in the quenching process. 2-methyltetrahydrofuran (60mL) was extracted twice, the oil layers were combined, evaporated to dryness under reduced pressure, added ethyl acetate to redissolve and filtered, evaporated again to dryness, and n-heptane/methyl tert-butyl ether (10/1) slurried to give 9.6 g of an off-white solid in 90% yield, HPLC: 99.8%, HNMR structure.
The foregoing embodiments have described the general principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the present invention, and that various changes and modifications may be made without departing from the scope of the principles of the present invention, and the invention is intended to be covered by the appended claims.

Claims (9)

1. The preparation method of the 4-phenoxyphenylboronic acid is characterized by comprising the following steps:
reacting diphenyl ether with a brominating reagent to generate 4,4' -dibromo diphenyl ether, reacting the intermediate with boric acid ester and n-butyl lithium, and hydrolyzing and purifying to obtain the 4-phenoxy phenylboronic acid.
2. The method for producing 4-phenoxyphenylboronic acid according to claim 1, wherein: NBS or bromine is used as a brominating reagent, wherein when the bromine is used, the reaction can be accelerated in the presence of Lewis acid and sodium bromate.
3. The method for producing 4-phenoxyphenylboronic acid according to claim 1, wherein: the reaction solvent is selected from tetrahydrofuran, water, methanol, ethanol, dichloromethane, 1, 2-dichloroethane, acetonitrile, acetone or ethyl acetate.
4. The method for producing 4-phenoxyphenylboronic acid according to claim 1, wherein: when in bromination reaction, the mol ratio of the bromination reagent to the diphenyl ether is 2-3: 1; the reaction temperature is-10 ℃ to 50 ℃.
5. The method for producing 4-phenoxyphenylboronic acid according to any one of claims 1 to 4, wherein: after bromination reaction, the purity of the obtained crude product can reach about 99.0 percent, and after one-time pulping and purification, the purity can reach more than 99.8 percent.
6. The method for producing 4-phenoxyphenylboronic acid according to claim 1, wherein: the 4,4 '-dibromodiphenyl ether, the boric acid ester and the n-butyllithium are carried out under the condition of a one-pot method, namely the 4,4' -dibromodiphenyl ether and the boric acid ester are mixed in a solvent, and the n-butyllithium is dripped.
7. The method for producing 4-phenoxyphenylboronic acid according to claim 1, wherein: the boric acid ester is selected from trimethyl borate, triethyl borate, triisopropyl borate or n-butyl borate.
8. The method for producing 4-phenoxyphenylboronic acid according to claim 1, wherein: the equivalent ratio of the 4,4' -dibromodiphenyl ether, the boric acid ester and the n-butyllithium is 1:1-1.1: 2-2.5.
9. The method for producing 4-phenoxyphenylboronic acid according to claim 1 or 6, wherein: when reacting with n-butyllithium, the reaction solvent is one or more selected from tetrahydrofuran, 2-methyltetrahydrofuran, diethoxymethane, cyclopentylmethyl ether, tert-butylmethyl ether and the like, or a mixture of the above solvents and toluene; the reaction temperature is controlled between-40 ℃ and-10 ℃.
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CN112321622A (en) * 2020-11-28 2021-02-05 沧州普瑞东方科技有限公司 Preparation method of N-aryl carbazole-3-boric acid
CN114874102A (en) * 2021-12-20 2022-08-09 青岛科技大学 A kind of method for preparing 4,4-diaminodiphenyl ether

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CN112321622A (en) * 2020-11-28 2021-02-05 沧州普瑞东方科技有限公司 Preparation method of N-aryl carbazole-3-boric acid
CN114874102A (en) * 2021-12-20 2022-08-09 青岛科技大学 A kind of method for preparing 4,4-diaminodiphenyl ether

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