CN115536489A - Green preparation process of high-purity 4-bromobiphenyl - Google Patents
Green preparation process of high-purity 4-bromobiphenyl Download PDFInfo
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- CN115536489A CN115536489A CN202211352522.9A CN202211352522A CN115536489A CN 115536489 A CN115536489 A CN 115536489A CN 202211352522 A CN202211352522 A CN 202211352522A CN 115536489 A CN115536489 A CN 115536489A
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- bromobiphenyl
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- biphenyl
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- PKJBWOWQJHHAHG-UHFFFAOYSA-N 1-bromo-4-phenylbenzene Chemical group C1=CC(Br)=CC=C1C1=CC=CC=C1 PKJBWOWQJHHAHG-UHFFFAOYSA-N 0.000 title claims abstract description 103
- 238000002360 preparation method Methods 0.000 title claims abstract description 22
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N diphenyl Chemical compound C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 claims abstract description 69
- 239000012043 crude product Substances 0.000 claims abstract description 66
- JHJLBTNAGRQEKS-UHFFFAOYSA-M sodium bromide Chemical compound [Na+].[Br-] JHJLBTNAGRQEKS-UHFFFAOYSA-M 0.000 claims abstract description 46
- 235000010290 biphenyl Nutrition 0.000 claims abstract description 36
- 239000004305 biphenyl Substances 0.000 claims abstract description 35
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 34
- CPELXLSAUQHCOX-UHFFFAOYSA-N Hydrogen bromide Chemical compound Br CPELXLSAUQHCOX-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000004821 distillation Methods 0.000 claims abstract description 17
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000006227 byproduct Substances 0.000 claims abstract description 13
- 238000004519 manufacturing process Methods 0.000 claims abstract description 13
- 229910000042 hydrogen bromide Inorganic materials 0.000 claims abstract description 11
- 239000003513 alkali Substances 0.000 claims abstract description 9
- KTADSLDAUJLZGL-UHFFFAOYSA-N 1-bromo-2-phenylbenzene Chemical group BrC1=CC=CC=C1C1=CC=CC=C1 KTADSLDAUJLZGL-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000003054 catalyst Substances 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims description 55
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 39
- 238000003756 stirring Methods 0.000 claims description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 35
- 239000000203 mixture Substances 0.000 claims description 34
- 239000007864 aqueous solution Substances 0.000 claims description 33
- 239000000243 solution Substances 0.000 claims description 26
- NLKNQRATVPKPDG-UHFFFAOYSA-M potassium iodide Inorganic materials [K+].[I-] NLKNQRATVPKPDG-UHFFFAOYSA-M 0.000 claims description 19
- 238000001816 cooling Methods 0.000 claims description 18
- 239000012074 organic phase Substances 0.000 claims description 18
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical group CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 16
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 16
- DWAQJAXMDSEUJJ-UHFFFAOYSA-M Sodium bisulfite Chemical compound [Na+].OS([O-])=O DWAQJAXMDSEUJJ-UHFFFAOYSA-M 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 16
- 239000010410 layer Substances 0.000 claims description 16
- 239000012044 organic layer Substances 0.000 claims description 16
- 239000002994 raw material Substances 0.000 claims description 16
- 238000007670 refining Methods 0.000 claims description 16
- 235000010267 sodium hydrogen sulphite Nutrition 0.000 claims description 16
- 239000007787 solid Substances 0.000 claims description 16
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 claims description 13
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 claims description 13
- 229910052794 bromium Inorganic materials 0.000 claims description 13
- 239000012071 phase Substances 0.000 claims description 10
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 9
- 239000003960 organic solvent Substances 0.000 claims description 9
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 8
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 8
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 claims description 8
- 238000005406 washing Methods 0.000 claims description 8
- 238000004090 dissolution Methods 0.000 claims description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 6
- 238000004064 recycling Methods 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 2
- 239000012065 filter cake Substances 0.000 claims description 2
- 239000012452 mother liquor Substances 0.000 claims description 2
- 235000011121 sodium hydroxide Nutrition 0.000 claims description 2
- 238000000967 suction filtration Methods 0.000 claims description 2
- 239000007795 chemical reaction product Substances 0.000 claims 1
- 239000000047 product Substances 0.000 abstract description 14
- 230000008901 benefit Effects 0.000 abstract description 7
- 238000005893 bromination reaction Methods 0.000 abstract description 6
- 238000003786 synthesis reaction Methods 0.000 abstract description 6
- 239000002904 solvent Substances 0.000 abstract description 5
- 238000001953 recrystallisation Methods 0.000 abstract description 4
- 238000009776 industrial production Methods 0.000 abstract description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 8
- 150000001875 compounds Chemical class 0.000 description 5
- 238000011084 recovery Methods 0.000 description 5
- WDFQBORIUYODSI-UHFFFAOYSA-N 4-bromoaniline Chemical compound NC1=CC=C(Br)C=C1 WDFQBORIUYODSI-UHFFFAOYSA-N 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000004321 preservation Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- FZERHIULMFGESH-UHFFFAOYSA-N N-phenylacetamide Chemical compound CC(=O)NC1=CC=CC=C1 FZERHIULMFGESH-UHFFFAOYSA-N 0.000 description 2
- 230000031709 bromination Effects 0.000 description 2
- 239000000543 intermediate Substances 0.000 description 2
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- GNYVCHUESISIAZ-UHFFFAOYSA-N 1,1'-biphenyl;1-bromo-4-phenylbenzene Chemical group C1=CC=CC=C1C1=CC=CC=C1.C1=CC(Br)=CC=C1C1=CC=CC=C1 GNYVCHUESISIAZ-UHFFFAOYSA-N 0.000 description 1
- GRZJZRHVJAXMRR-UHFFFAOYSA-N 1-cyclohexyl-2-phenylbenzene Chemical group C1CCCCC1C1=CC=CC=C1C1=CC=CC=C1 GRZJZRHVJAXMRR-UHFFFAOYSA-N 0.000 description 1
- RLOSRCUFYXDHPG-UHFFFAOYSA-N N#[C-].C1=CC=CC=C1C1=CC=CC=C1 Chemical compound N#[C-].C1=CC=CC=C1C1=CC=CC=C1 RLOSRCUFYXDHPG-UHFFFAOYSA-N 0.000 description 1
- 229920002472 Starch Polymers 0.000 description 1
- 229960001413 acetanilide Drugs 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- -1 alkyl biphenyl Chemical compound 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 150000004074 biphenyls Chemical class 0.000 description 1
- 150000001841 cholesterols Chemical class 0.000 description 1
- WBYWAXJHAXSJNI-UHFFFAOYSA-N cinnamic acid Chemical class OC(=O)C=CC1=CC=CC=C1 WBYWAXJHAXSJNI-UHFFFAOYSA-N 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 125000004093 cyano group Chemical group *C#N 0.000 description 1
- IGARGHRYKHJQSM-UHFFFAOYSA-N cyclohexylbenzene Chemical class C1CCCCC1C1=CC=CC=C1 IGARGHRYKHJQSM-UHFFFAOYSA-N 0.000 description 1
- 125000000664 diazo group Chemical group [N-]=[N+]=[*] 0.000 description 1
- 239000012954 diazonium Substances 0.000 description 1
- 238000006193 diazotization reaction Methods 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-O diazynium Chemical compound [NH+]#N IJGRMHOSHXDMSA-UHFFFAOYSA-O 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012454 non-polar solvent Substances 0.000 description 1
- 239000002798 polar solvent Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 235000010288 sodium nitrite Nutrition 0.000 description 1
- 235000019698 starch Nutrition 0.000 description 1
- 239000008107 starch Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
- C07C17/10—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms
- C07C17/12—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms in the ring of aromatic compounds
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/10—Bromides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/14—Purification
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/38—Separation; Purification; Stabilisation; Use of additives
- C07C17/383—Separation; Purification; Stabilisation; Use of additives by distillation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/38—Separation; Purification; Stabilisation; Use of additives
- C07C17/392—Separation; Purification; Stabilisation; Use of additives by crystallisation; Purification or separation of the crystals
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/38—Separation; Purification; Stabilisation; Use of additives
- C07C17/395—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to a chemical modification of at least one compound
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a green preparation process of high-purity 4-bromobiphenyl, belonging to the technical field of chemical synthesis; hydrogen peroxide is used as a positioning catalyst, biphenyl is dissolved in dichloroethane for bromination reaction, so that a 4-bromobiphenyl crude product is prepared, and the yield is over 60 percent; the crude product is rectified under reduced pressure and recrystallized, and the content of the product reaches more than 99 percent; the dichloroethane used in the production process can be reused after redistillation; absorbing the generated hydrogen bromide by alkali liquor to obtain a byproduct sodium bromide; the solvent for recrystallization can be reused after distillation, and the byproduct 2-bromobiphenyl is recovered; the preparation process has the advantages of high product yield, high product purity after rectification, recyclable byproducts generated in the production process, less three wastes, recyclable solvent and high economic benefit, and is suitable for industrial production.
Description
Technical Field
The invention belongs to the technical field of chemical synthesis, and particularly relates to a green preparation process of high-purity 4-bromobiphenyl.
Background
4-bromobiphenyl is widely used for liquid crystal materials or electronic chemical intermediates, is a key intermediate in the preparation of liquid crystal compounds, and alkyl biphenyl and cyclohexyl biphenyl can be prepared from the bromobiphenyl. Then introducing cyano to prepare a common biphenyl cyanide liquid crystal compound; the biphenyl 4-bromobiphenyl has outstanding performance advantages in synthesizing biphenyl liquid crystal compounds, and the liquid crystal compounds are various in types and can be divided into aromatic esters, cinnamates, biphenyls, phenylcyclohexanes, cholesterol derivatives and chiral liquid crystals according to the structural characteristics of central bridges and rings forming liquid crystal molecules.
The synthesis of the liquid crystal compounds is generally carried out by adopting a corresponding organic synthesis method without a special method. The synthesis method of 4-bromobiphenyl is generally characterized by using p-bromoaniline to carry out Gomberg reaction, cooling water, p-bromoaniline and concentrated hydrochloric acid together, keeping the temperature at 0-5 ℃, slowly adding sodium nitrite aqueous solution, carrying out diazotization until starch potassium iodide test paper is blue, and filtering out clarified diazonium solution; adding benzene into the diazo solution, stirring at 5-10 deg.C for half an hour, slowly adding dropwise sodium hydroxide water solution, stirring for 3 hr, and stirring at room temperature for 45 hr; the p-bromoaniline is prepared by bromination of acetanilide, the method has long synthesis route, strong acid and strong base are needed in the reaction process, potential safety hazards exist, the yield is only about 35%, and the produced product is easy to ash after being placed for a long time. The japanese Chisso company uses bromine as a direct bromination in acetic acid, a polar solvent, with a yield of 34%. Standohui et al, the chemical series of Qinghua university, bromize directly in the nonpolar solvent carbon tetrachloride with a yield of 32%. The above synthesis methods all have the problems of low product yield, high reaction cost, many byproducts, long reaction steps and troublesome post-treatment.
Therefore, the research and development of a synthesis process of 4-bromobiphenyl, which has the advantages of simple preparation process, high product yield and purity and low production cost, becomes an urgent problem to be solved.
Disclosure of Invention
In order to solve the problems, the invention aims to provide a green preparation process of high-purity 4-bromobiphenyl. Hydrogen peroxide is used as a positioning catalyst, biphenyl is dissolved in dichloroethane for bromination reaction, so as to prepare a 4-bromobiphenyl crude product, and the yield is 60%; the crude product is rectified under reduced pressure and recrystallized, and the content of the product reaches more than 99 percent; the dichloroethane used in the production process can be reused after redistillation; absorbing the generated hydrogen bromide by alkali liquor to obtain a byproduct sodium bromide; the solvent for recrystallization can be reused by distillation, and the byproduct 2-bromobiphenyl is recovered.
In order to achieve the purpose, the invention is realized by the following technical scheme:
a green preparation process of high-purity 4-bromobiphenyl comprises the following steps:
(1) Preparation of crude 4-bromobiphenyl: adding dichloroethane and biphenyl into a reaction kettle, stirring and cooling to-10 to 0 ℃, then adding bromine and a catalyst hydrogen peroxide into the reaction kettle, controlling the reaction temperature to be-5 to 0 ℃, reacting for 3 to 8 hours, after the reaction is finished, heating to be 25 to 30 ℃, carrying out a heat preservation reaction for 24 to 32 hours, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution for recovering a sodium bromide crude product, after the reaction is finished, adding a sodium bisulfite aqueous solution, stirring for 30 to 60 minutes, detecting by using a starch-potassium iodide test paper to be white, adjusting the pH of the solution to be 7.5 to 8 by using 0.01mol/L diluted alkali, stirring for 30 to 60 minutes, standing and layering to obtain a water layer and an organic layer, and recovering the water layer to obtain a sodium bromide crude product;
washing the organic layer with water for 3 to 5 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
the molar ratio of the biphenyl to the bromine to the hydrogen peroxide is as follows: 1:0.4 to 0.8:1 to 1.5;
the mass concentration of the hydrogen peroxide is 25 to 30 percent;
the mass concentration of the sodium hydroxide aqueous solution is 35 to 45 percent;
the mass concentration of the sodium bisulfite aqueous solution is 5 to 15 percent;
the mass ratio of the sodium bisulfite aqueous solution to the biphenyl is 1 to 1.2:2;
the dilute alkali solution is an aqueous solution of sodium hydroxide, sodium bicarbonate or sodium bisulfite, and the mass concentration is 5 to 10 percent;
the distillation temperature of the organic phase is 80 to 90 ℃, and the collected fraction is dichloroethane;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: carrying out reduced pressure distillation on the crude product of 4-bromobiphenyl obtained in the step (1), collecting a mixture of biphenyl with a temperature below 161 ℃ and 4-bromobiphenyl, using the mixture as a raw material, and collecting a crude product of the 4-bromobiphenyl of a main fraction at a temperature of 161-163 ℃;
wherein the reduced pressure distillation pressure is-0.09 MPa, and the temperature is 180-200 ℃;
(3) Refining the 4-bromobiphenyl crude product: adding the crude 4-bromobiphenyl obtained in the step (2) into an organic solvent, stirring and heating to 50-75 ℃ for dissolution, then cooling to-10-0 ℃, centrifuging after solid is separated out, collecting centrifugate, collecting the solid obtained by centrifuging through reduced pressure distillation, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, and collecting the refined 4-bromobiphenyl of the main fraction at 161-163 ℃;
the organic solvent is ethanol, benzene, acetone or carbon tetrachloride;
wherein the reduced pressure distillation pressure is-0.09 MPa, and the temperature is 180-200 ℃.
Preferably, in the step (1), the molar ratio of the biphenyl to the bromine to the hydrogen peroxide is as follows: 1:0.5:1.2.
preferably, the mass concentration of the sodium bisulfite aqueous solution in the step (1) is 10%.
Distilling the crude sodium bromide in the step (1) at 120 ℃, then cooling to 0-10 ℃, crystallizing, and carrying out suction filtration, and drying the obtained filter cake to obtain a byproduct sodium bromide.
And (2) recycling the water phase in the step (1) for use in preparing a dilute alkali solution.
And (4) distilling the collected centrifugate in the step (3), recovering and recycling the distillate which is an organic solvent, and recovering the residual distilled mother liquor which is 2-bromobiphenyl as a byproduct.
Preferably, the organic solvent in the step (3) is ethanol, and the organic solvent is heated to 70 ℃ and cooled to-5 ℃.
The reaction principle of the 4-bromobiphenyl of the invention is as follows:
(1) Bromination reaction:
(2) Side reaction:
compared with the prior art, the invention has the following advantages:
the invention relates to a green preparation process of high-purity 4-bromobiphenyl, which adopts hydrogen peroxide as a positioning catalyst, and dissolves biphenyl in dichloroethane for bromination reaction to prepare a crude product of 4-bromobiphenyl, wherein the yield is over 60 percent; the crude product is subjected to pressure rectification and recrystallization, and the content of the product reaches over 99 percent; the dichloroethane used in the production process can be reused by redistillation; absorbing the generated hydrogen bromide by alkali liquor to obtain a byproduct sodium bromide; the solvent for recrystallization can be reused after distillation, and the byproduct 2-bromobiphenyl is recovered.
The green preparation process of the high-purity 4-bromobiphenyl has the advantages of high product yield, high product purity after rectification, recoverable by-product generated in the production process, less three wastes, recoverable solvent, realization of the purpose of green production, high process economic benefit and suitability for industrial production.
Detailed Description
The invention aims to provide a green preparation process of high-purity 4-bromobiphenyl, which is realized by the following technical scheme:
the invention is further described with reference to specific examples.
Example 1
(1) Preparation of crude 4-bromobiphenyl: adding 6000 ml of dichloroethane and 3.08 kg of biphenyl into a reaction kettle, stirring and cooling to-10 ℃, then adding 1.28 kg of bromine and 2.72 kg of hydrogen peroxide with the mass concentration of 25%, controlling the reaction temperature to be-5 ℃, reacting for 3h, after the reaction is finished, heating to 25 ℃, keeping the temperature and reacting for 24h, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution with the mass concentration of 35% for recovering a sodium bromide crude product, after the reaction is finished, adding 1.54kg of a sodium bisulfite aqueous solution with the mass concentration of 5%, stirring for 30min, detecting by using a starch-potassium iodide test paper to obtain white, adjusting the pH of the solution to 7.5 by using a 0.01mol/L sodium bicarbonate aqueous solution, stirring for 30min, standing and layering to obtain a water layer and an organic layer, wherein the water layer is subjected to recovery treatment to obtain the sodium bromide crude product;
washing the organic layer with water for 3 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: carrying out reduced pressure distillation on the 4-bromobiphenyl crude product obtained in the step (1) at the temperature of-0.09MPa and 180 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl at the temperature of less than 161 ℃, mechanically using the mixture as a raw material, and collecting a main fraction of the 4-bromobiphenyl crude product at the temperature of 161-163 ℃;
(3) Refining the 4-bromobiphenyl crude product: adding the crude 4-bromobiphenyl product obtained in the step (2) into 5000ml of acetone, stirring and heating to 50 ℃ for dissolving, then cooling to-10 ℃, centrifuging after solid is separated out, collecting centrifugate, distilling the solid obtained by centrifuging under reduced pressure of-0.09MPa and 180 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, mechanically using the mixture as a raw material, collecting 3.51kg of the refined 4-bromobiphenyl product of the main fraction at 161 to 163 ℃, wherein the yield is 75.3 percent and the purity is 99.3 percent.
Example 2
(1) Preparation of a crude product of 4-bromobiphenyl: adding 6000 ml of dichloroethane and 3.08 kg of biphenyl into a reaction kettle, stirring and cooling to-5 ℃, then adding 1.60kg of bromine and 2.99 kg of hydrogen peroxide with the mass concentration of 25% into the reaction kettle, controlling the reaction temperature to be-3 ℃, reacting for 4h, after the reaction is finished, heating to 27 ℃, keeping the temperature and reacting for 26h, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution with the mass concentration of 40% for recovering a sodium bromide crude product, after the reaction is finished, adding 1.69kg of a sodium bisulfite aqueous solution with the mass concentration of 8%, stirring for 40min, detecting the mixture to be white by using a starch-potassium iodide test paper, adjusting the pH of the solution to 7.7 by using a 0.01mol/L sodium bicarbonate aqueous solution, stirring for 40min, standing and layering to obtain a water layer and an organic layer, wherein the water layer is subjected to recovery treatment to obtain the sodium bromide crude product;
washing the organic layer with water for 4 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: carrying out reduced pressure distillation on the 4-bromobiphenyl crude product obtained in the step (1) at the temperature of-0.09MPa and 185 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl at the temperature of less than 161 ℃, mechanically using the mixture as a raw material, and collecting a main fraction of the 4-bromobiphenyl crude product at the temperature of 161-163 ℃;
(3) Refining the 4-bromobiphenyl crude product: adding the crude 4-bromobiphenyl obtained in the step (2) into 5000ml of carbon tetrachloride, stirring and heating to 60 ℃ for dissolution, then cooling to-7 ℃, centrifuging after solid is separated out, collecting centrifugate, distilling the solid obtained by centrifuging under reduced pressure at-0.09MPa and 185 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, collecting 3.56kg of the refined 4-bromobiphenyl as of the main fraction at 161 to 163 ℃, wherein the yield is 76.4 percent and the purity is 99.4 percent.
Example 3
(1) Preparation of crude 4-bromobiphenyl: adding 6000 ml of dichloroethane and 3.08 kg of biphenyl into a reaction kettle, stirring and cooling to-8 ℃, then adding 1.92 kg of bromine and 2.43kg of hydrogen peroxide with the mass concentration of 28% into the reaction kettle, controlling the reaction temperature to be-3 ℃, reacting for 6h, after the reaction is finished, heating to 28 ℃, carrying out heat preservation reaction for 30h, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution with the mass concentration of 35% for recovering a sodium bromide crude product, after the reaction is finished, adding 1.77 kg of a sodium bisulfite aqueous solution with the mass concentration of 12%, stirring for 40min, detecting the solution to be white by using a starch-potassium iodide test paper, adjusting the pH of the solution to 8 by using a 0.01mol/L sodium bicarbonate aqueous solution, stirring for 50 min, standing and layering to obtain a water layer and an organic layer, wherein the water layer is subjected to recovery treatment to obtain a sodium bromide crude product;
washing the organic layer with water for 4 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: carrying out reduced pressure distillation on the 4-bromobiphenyl crude product obtained in the step (1) at-0.09MPa and 190 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl at a temperature of below 161 ℃, mechanically using the mixture as a raw material, and collecting a main fraction 4-bromobiphenyl crude product at a temperature of 161 to 163 ℃;
(3) Refining the crude product of 4-bromobiphenyl: adding the crude 4-bromobiphenyl obtained in the step (2) into 5000ml of ethanol, stirring and heating to 75 ℃ for dissolution, then cooling to-5 ℃, centrifuging after solid is separated out, collecting centrifugate, distilling the solid obtained by centrifuging under reduced pressure at-0.09MPa and 190 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, collecting 3.58g of the refined 4-bromobiphenyl as of the main fraction at 161 to 163 ℃, wherein the yield is 76.8 percent, and the purity is 99.4 percent.
Example 4
(1) Preparation of a crude product of 4-bromobiphenyl: adding 6000 ml of dichloroethane and 3.08 kg of biphenyl into a reaction kettle, stirring and cooling to 0 ℃, then adding 2.56 kg of bromine and 3.4kg of hydrogen peroxide with the mass concentration of 30% into the reaction kettle, controlling the reaction temperature to be 0 ℃, reacting for 8 hours, after the reaction is finished, heating to 30 ℃, carrying out heat preservation reaction for 32 hours, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution with the mass concentration of 45% for recovering a sodium bromide crude product, after the reaction is finished, adding 1.85 kg of a sodium bisulfite aqueous solution with the mass concentration of 15%, stirring for 60 minutes, adjusting the pH of the solution to 8 by using a 0.01mol/L sodium bicarbonate aqueous solution after detecting the solution to be white by using a starch-potassium iodide test paper, stirring for 60 minutes, standing and layering to obtain a water layer and an organic layer, wherein the water layer is subjected to recovery treatment to obtain a sodium bromide crude product;
washing the organic layer with water for 5 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: distilling the crude product of 4-bromobiphenyl obtained in the step (1) under reduced pressure at-0.09MPa and 200 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl at a temperature of below 161 ℃, mechanically applying the mixture as a raw material, and collecting a main fraction of the crude product of 4-bromobiphenyl at a temperature of between 161 and 163 ℃;
(3) Refining the crude product of 4-bromobiphenyl: adding the crude 4-bromobiphenyl obtained in the step (2) into 5000ml of ethanol, stirring and heating to 75 ℃ for dissolution, then cooling to 0 ℃, centrifuging after solid is separated out, collecting centrifugate, distilling the solid obtained by centrifuging under reduced pressure at-0.09MPa and 200 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, collecting 3.52 kg of the refined 4-bromobiphenyl product of the main fraction at 161 to 163 ℃, wherein the yield is 75.5% and the purity is 99.3%.
Example 5
(1) Preparation of a crude product of 4-bromobiphenyl: adding 6000 ml of dichloroethane and 3.08 kg of biphenyl into a reaction kettle, stirring and cooling to-5 ℃, then adding 1.60kg of bromine and 2.72 kg of hydrogen peroxide with the mass concentration of 30% into the reaction kettle, controlling the reaction temperature to be-5 ℃, reacting for 5h, after the reaction is finished, heating to 30 ℃, preserving heat and reacting for 28h, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution with the mass concentration of 38% for recovering a sodium bromide crude product, after the reaction is finished, adding 1.85 kg of a sodium bisulfite aqueous solution with the mass concentration of 10%, stirring for 60min, detecting the solution to be white by using a starch-potassium iodide test paper, adjusting the pH of the solution to be 7.5 by using a 0.01mol/L sodium bicarbonate aqueous solution, stirring for 45 min, standing and layering to obtain a water layer and an organic layer, and recovering the water layer to obtain the sodium bromide crude product;
washing the organic layer with water for 3 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: distilling the crude product of 4-bromobiphenyl obtained in the step (1) under reduced pressure at-0.09MPa and 200 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl at a temperature of below 161 ℃, mechanically applying the mixture as a raw material, and collecting a main fraction of the crude product of 4-bromobiphenyl at a temperature of between 161 and 163 ℃;
(3) Refining the 4-bromobiphenyl crude product: adding the crude 4-bromobiphenyl obtained in the step (2) into 5000ml of ethanol, stirring and heating to 70 ℃ for dissolution, then cooling to-5 ℃, centrifuging after solid is separated out, collecting centrifugate, distilling the solid obtained by centrifuging under reduced pressure at-0.09MPa and 200 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, collecting 3.68 kg of the refined 4-bromobiphenyl as the main fraction at 161 to 163 ℃, wherein the yield is 79.0 percent and the purity is 99.5 percent.
Example 6
(1) Preparation of a crude product of 4-bromobiphenyl: adding 6000 ml of dichloroethane and 3.08 kg of biphenyl into a reaction kettle, stirring and cooling to-3 ℃, then adding 1.92 kg of bromine and 2.72 kg of hydrogen peroxide with the mass concentration of 30% into the reaction kettle, controlling the reaction temperature to be-5 ℃, reacting for 7h, after the reaction is finished, heating to 25 ℃, keeping the temperature and reacting for 30h, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution with the mass concentration of 42% for recovering a sodium bromide crude product, after the reaction is finished, adding 1.54kg of a sodium bisulfite aqueous solution with the mass concentration of 10%, stirring for 45 min, detecting the mixture to be white by using a starch-potassium iodide test paper, adjusting the pH of the solution to 7.8 by using a 0.01mol/L sodium bicarbonate aqueous solution, stirring for 60min, standing and layering to obtain a water layer and an organic layer, wherein the water layer is subjected to recovery treatment to obtain the sodium bromide crude product;
washing the organic layer with water for 3 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: carrying out reduced pressure distillation on the 4-bromobiphenyl crude product obtained in the step (1) at 200 ℃ under the pressure of-0.09MPa, collecting a mixture of biphenyl and 4-bromobiphenyl at the temperature of below 161 ℃, mechanically using the mixture as a raw material, and collecting a main fraction 4-bromobiphenyl crude product at the temperature of 161-163 ℃;
(3) Refining the 4-bromobiphenyl crude product: adding the crude 4-bromobiphenyl obtained in the step (2) into 5000ml of ethanol, stirring and heating to 70 ℃ for dissolution, then cooling to-5 ℃, centrifuging after solid is separated out, collecting centrifugate, distilling the solid obtained by centrifuging under reduced pressure at-0.09MPa and 200 ℃, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, collecting 3.61 kg of the refined 4-bromobiphenyl product of the main fraction at 161 to 163 ℃, wherein the yield is 77.5 percent, and the purity is 99.4 percent.
Claims (7)
1. A green preparation process of high-purity 4-bromobiphenyl is characterized by comprising the following steps: the method comprises the following steps:
(1) Preparation of a crude product of 4-bromobiphenyl: adding dichloroethane and biphenyl into a reaction kettle, stirring and cooling to-10 to 0 ℃, then adding bromine and a catalyst hydrogen peroxide into the reaction kettle, controlling the reaction temperature to-5 to 0 ℃, reacting for 3 to 8 hours, after the reaction is finished, heating to 25 to 30 ℃, keeping the temperature and reacting for 24 to 32 hours, introducing hydrogen bromide generated in the reaction process into a sodium hydroxide aqueous solution for recovering a sodium bromide crude product, after the reaction is finished, adding a sodium bisulfite aqueous solution, stirring for 30 to 60 minutes, detecting the reaction product to be white by using a starch-potassium iodide test paper, adjusting the pH of the solution to 7.5 to 8 by using 0.01mol/L dilute alkali, stirring for 30 to 60 minutes, standing and layering to obtain a water layer and an organic layer, and recovering the water layer to obtain the sodium bromide crude product;
washing the organic layer with water for 3 to 5 times, collecting and combining to obtain a water phase and an organic phase, and distilling and concentrating the organic phase to obtain a concentrated solution, namely a crude product of 4-bromobiphenyl;
the molar ratio of the biphenyl to the bromine to the hydrogen peroxide is as follows: 1:0.4 to 0.8:1 to 1.5;
the mass concentration of the hydrogen peroxide is 25 to 30 percent;
the mass concentration of the sodium hydroxide aqueous solution is 35 to 45 percent;
the mass concentration of the sodium bisulfite aqueous solution is 5 to 15 percent;
the mass ratio of the sodium bisulfite aqueous solution to the biphenyl is 1 to 1.2:2;
the dilute alkali solution is an aqueous solution of sodium hydroxide, sodium bicarbonate or sodium bisulfite, and the mass concentration is 5 to 10 percent;
the distillation temperature of the organic phase is 80 to 90 ℃, and the collected fraction is dichloroethane;
(2) Pretreatment of refining of a 4-bromobiphenyl crude product: carrying out reduced pressure distillation on the crude 4-bromobiphenyl obtained in the step (1), collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, mechanically applying the mixture as a raw material, and collecting a main fraction of the crude 4-bromobiphenyl at 161 to 163 ℃;
wherein the reduced pressure distillation pressure is-0.09 MPa, and the temperature is 180-200 ℃;
(3) Refining the crude product of 4-bromobiphenyl: adding the crude 4-bromobiphenyl obtained in the step (2) into an organic solvent, stirring and heating to 50-75 ℃ for dissolution, then cooling to-10-0 ℃, centrifuging after solid is separated out, collecting centrifugate, collecting the solid obtained by centrifuging through reduced pressure distillation, collecting a mixture of biphenyl and 4-bromobiphenyl below 161 ℃, using the mixture as a raw material, and collecting the refined 4-bromobiphenyl of the main fraction at 161-163 ℃;
the organic solvent is ethanol, benzene, acetone or carbon tetrachloride;
wherein the reduced pressure distillation pressure is-0.09 MPa, and the temperature is 180-200 ℃.
2. The green process for preparing high-purity 4-bromobiphenyl as claimed in claim 1, which is characterized in that: in the step (1), the molar ratio of the biphenyl to the bromine to the hydrogen peroxide is as follows: 1:0.5:1.2.
3. the green process for preparing high-purity 4-bromobiphenyl as claimed in claim 1, which is characterized in that: the mass concentration of the sodium bisulfite aqueous solution in the step (1) is 10%.
4. The green process for preparing high-purity 4-bromobiphenyl according to claim 1, which is characterized in that: distilling the sodium bromide crude product in the step (1) at 120 ℃, then cooling to 0-10 ℃, crystallizing, performing suction filtration, and drying the obtained filter cake to obtain a byproduct sodium bromide.
5. The green process for preparing high-purity 4-bromobiphenyl according to claim 1, which is characterized in that: and (2) recycling the water phase in the step (1) for use in preparation of a dilute alkali solution.
6. The green process for preparing high-purity 4-bromobiphenyl as claimed in claim 1, which is characterized in that: and (4) distilling the collected centrifugate in the step (3), recovering and recycling the distillate which is an organic solvent, and recovering the residual distilled mother liquor which is 2-bromobiphenyl as a byproduct.
7. The green process for preparing high-purity 4-bromobiphenyl according to claim 1, which is characterized in that: in the step (3), the organic solvent is ethanol, the temperature is heated to 70 ℃, and the temperature is reduced to-5 ℃.
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| CN116640041A (en) * | 2023-05-30 | 2023-08-25 | 南京先进生物材料与过程装备研究院有限公司 | Method and system for preparing 4-bromodiphenyl and derivative thereof |
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