CN104140362B - A kind of preparation method of m fluorophenol - Google Patents
A kind of preparation method of m fluorophenol Download PDFInfo
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- CN104140362B CN104140362B CN201410337357.9A CN201410337357A CN104140362B CN 104140362 B CN104140362 B CN 104140362B CN 201410337357 A CN201410337357 A CN 201410337357A CN 104140362 B CN104140362 B CN 104140362B
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- difluorobenzene
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/01—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis
- C07C37/02—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis by substitution of halogen
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Abstract
The invention discloses a kind of preparation method of m fluorophenol, the method comprises the steps: A, in the reactor containing ptfe plastic lining, add potassium hydroxide, dimethyl sulfoxide (DMSO) and water, be warming up to 120-140 degree, drip m-difluorobenzene, in dropping process, make unreacted m-difluorobenzene return in reaction substrate by condenser; After B, m-difluorobenzene dropwise, back flow reaction to liquid temperature reaches 140-150 degree, after reaction 4-6h, be cooled to 26-34 degree, decompression 3-6KPa steams solvent, steam to liquid temperature 140-160 degree, reaction solution is poured in frozen water, regulate PH=3-5, use extracted with diethyl ether product, steam solvent, obtain m fluorophenol product.The present invention significantly can shorten operational path prepared by m fluorophenol, significantly improves the yield of product compared with prior art simultaneously, possesses safety, cheapness, environmental protection, feature without the need to special equipment simultaneously.
Description
Technical field
The present invention relates to a kind of technical field of fine, especially a kind of high efficiency preparation method of m fluorophenol.
Background technology
M fluorophenol is as a kind of important fine-chemical intermediate, and at medicine, liquid crystal, the fields such as agricultural chemicals have and use widely.Along with continually developing of some special propertys of fluorochemicals, in recent years fluorochemicals development & production entered into brand-new period, m fluorophenol is as important fluoro-containing intermediate, and its market requirement also increases greatly.
At present, the technique about m fluorophenol of various bibliographical information mainly contains three classes,
One, amino-phenol is that raw material prepares m fluorophenol through schiemann reaction, namely Metha Amino Phenon in acid condition with Sodium Nitrite generation diazotization reaction, generate the diazonium salt of fluoroboric acid or hydrofluoric acid, then extract diazonium salt, by diazonium salt thermal degradation to m fluorophenol, the pyrolytic process of this technique is dangerous, operational condition is harsh, and industrialization difficulty is larger
Two, adopt m-fluoroaniline to be that m fluorophenol prepared by raw material, namely m-fluoroaniline carries out diazotization reaction, is then hydrolyzed into product m fluorophenol.This kind of complex operation, condition is harsh, and reaction solution still has larger danger, and reaction generates more by product, and yield is unstable.
Three, adopt the oxidation of 3-fluorophenyl methyl diethoxy silane to prepare m fluorophenol, this kind of raw materials technology is rare, and high cost, is not suitable for industrial production.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of preparation method of m fluorophenol, significantly can shorten operational path prepared by m fluorophenol, significantly improve the yield of product compared with prior art simultaneously, possess safety, cheapness, environmental protection, feature without the need to special equipment simultaneously.
For solving the problems of the technologies described above, the technical solution used in the present invention is as follows.
A preparation method for m fluorophenol, the method comprises the steps:
A, in the reactor containing ptfe plastic lining, add potassium hydroxide, dimethyl sulfoxide (DMSO) and water, be warming up to 120-140 degree, drip m-difluorobenzene, in dropping process, make unreacted m-difluorobenzene return in reaction substrate by condenser;
After B, m-difluorobenzene dropwise, back flow reaction to liquid temperature reaches 140-150 degree, after reaction 4-6h, be cooled to 26-34 degree, decompression 3-6KPa steams solvent, steam to liquid temperature 140-160 degree, reaction solution is poured in frozen water, regulate PH=3-5, use extracted with diethyl ether product, steam solvent, obtain m fluorophenol product.
As a preferred technical solution of the present invention, in steps A, the mol ratio of m-difluorobenzene and potassium hydroxide is 1:5.6-5.8; The mass ratio of m-difluorobenzene and dimethyl sulfoxide (DMSO) is 1:8-12; The mass ratio of water and dimethyl sulfoxide (DMSO) is 1:3.5-4.5; The temperature dripping reaction system during m-difluorobenzene is 125-130 degree.
As a preferred technical solution of the present invention, in steps A, the mol ratio of m-difluorobenzene and potassium hydroxide is 1:5.8; The mass ratio of m-difluorobenzene and dimethyl sulfoxide (DMSO) is 1:11; The mass ratio of water and dimethyl sulfoxide (DMSO) is 1:4; The temperature dripping reaction system during m-difluorobenzene is 128 degree.
As a preferred technical solution of the present invention, in step B, back flow reaction to liquid temperature reaches 144-146 degree, and the reaction times is 4.5-5.5h, is cooled to 28-32 degree, regulates PH=3.5-4.5 after steaming solvent with concentrated hydrochloric acid after reaction terminates; The mass volume ratio of m-difluorobenzene and extraction agent ether is 1:12-15.
As a preferred technical solution of the present invention, in step B, back flow reaction to liquid temperature reaches 145 degree, and the reaction times is 5h, is cooled to 30 degree, regulates PH=4 after steaming solvent with concentrated hydrochloric acid after reaction terminates; The mass volume ratio of m-difluorobenzene and extraction agent ether is 1:14.
As a preferred technical solution of the present invention, the method comprises the steps, the volume wherein related to or volume, all adopts mL to be unit; The quality related to or weight, all adopt g to be unit; A, on the four-hole bottle of 10000 volume parts, install mechanical stirring, constant pressure funnel, prolong and thermometer additional, and logical argon gas is protected, then potassium hydroxide 1305 weight part, dimethyl sulfoxide (DMSO) 5500 weight part and water 1300 weight part is added, be warming up to 130 degree, start to drip m-difluorobenzene, add the m-difluorobenzene of 463 weight parts in 40min, make unreacted m-difluorobenzene turn back in reaction substrate by condenser by prolong; After B, m-difluorobenzene dropwise, back flow reaction to liquid temperature reaches 145 degree, stops heating, logical argon gas is cooled to 30 degree, decompression 5KPa steams solvent, and steaming to liquid temperature is 150 degree, pours in the frozen water of 9000 weight parts, PH=4 is acidified to the concentrated hydrochloric acid of 1700 parts by volume, stir 30min, divide three extractions with the ether of 6000 parts by volume, through dried over sodium sulfate, filter, drain, recycling design, decompression precipitation, obtain crude product 386.4 weight part.
The beneficial effect adopting technique scheme to produce is:
Have report in the reaction document at home and abroad that m fluorophenol is produced in m-difluorobenzene hydrolysis, the problem generally reflected is exactly: reaction yield is low, and by product is many, separation difficulty more.Its highest yield can only be accomplished less than 60 percent, and circulation ratio extreme difference.This programme is thought, always makes its anhydrous and oxygen-free to reach the object optimizing reaction as much as possible in generic reaction in the past for the use of dimethyl sulfoxide (DMSO), and this so does also really effectively for great majority reaction.But the hydrolysis of m-difluorobenzene is to solvent, and temperature of reaction, base strength has special requirement, and this reaction changes polarity and the dispersiveness of solvent with a kind of distinct thinking.Adding of water not only makes organic phase and inorganic phase obtain suitable transfer rate, prevent the side reaction produced due to strong alkaline condition, simultaneously, water exists as reactant, the process of reaction itself is made to there occurs change, become smooth steady, the process for reaction has had great improvement, therefore well improves selectivity and the yield of reaction.
Therefore, although also there is foreign language literature report to use the method for hydrolysis that m-difluorobenzene is hydrolyzed into m fluorophenol at present, its method reaction yield is low, and by product is a lot, has practical value hardly.The present invention take m-difluorobenzene as starting raw material, m-difluorobenzene is hydrolyzed in strong basicity environment and falls a fluorine atom and obtain m fluorophenol, route is short, simple to operate, easily purifying strong without the need to special equipment, reaction preference, compare also more safe with the technique used now, adopt operational path of the present invention and processing parameter thereof, the yield of product is made to reach more than 85%, there is unexpected technique effect (test example that concrete data are listed vide infra), compared with prior art have and significantly improve.
Embodiment
Following examples describe the present invention in detail.Various raw material used in the present invention and items of equipment are conventional commercial product, all can be bought by market and directly obtain.The specification of part material of the present invention is as following table:
| Title | Specification |
| M-difluorobenzene | 99％ |
| Potassium hydroxide | Technical pure |
| Dimethyl sulfoxide (DMSO) | Technical pure |
| Ether | Technical pure |
| Water | Tap water |
| Hydrochloric acid | 14mol/L |
The preparation method of embodiment 1, m fluorophenol
A preparation method for m fluorophenol, comprises the steps that (volume wherein related to or volume, all adopt mL to be unit; The quality related to or weight, all adopt g to be unit):
A, on the four-hole bottle of 10000 volume parts, install mechanical stirring, constant pressure funnel, prolong and thermometer additional, for prolong wherein, spherical or the straight pipe condensation device of conventional employing in laboratory, the present invention adopts coil condenser and is B-grade condensation, phlegma noncirculating water, more easily realizes under factory condition; Said apparatus leads to argon gas protection, then potassium hydroxide 1305 weight part, dimethyl sulfoxide (DMSO) 5500 weight part and water 1300 weight part is added, be warming up to 130 degree, start to drip m-difluorobenzene, add the m-difluorobenzene of 463 weight parts in 40min, make unreacted m-difluorobenzene turn back in reaction substrate by condenser by prolong;
After B, m-difluorobenzene dropwise, back flow reaction to liquid temperature reaches 145 degree, stop heating, logical argon gas is cooled to 30 degree, decompression 5KPa (pressure value is that vacuum pump reaches maximum value) steams solvent, steaming to liquid temperature is 150 degree, pour in the frozen water of 9000 weight parts, PH=4 is acidified to the concentrated hydrochloric acid of 1700 parts by volume, stir 30min, divide three extractions with the ether of 6000 parts by volume, through dried over sodium sulfate, filter, drain, recycling design, decompression precipitation, obtain crude product 386.4 weight part; Total recovery is 85.6%.
The ratio Selecting research of embodiment 2, m-difluorobenzene (A) and potassium hydroxide (B), related data gathers as following table:
| B/A (mol ratio) | Product purity | Yield |
| 4.5：1 | 98％ | 55％ |
| 5.8：1 | 98.5％ | 85％ |
| 6.5：1 | 97％ | 84％ |
| 7：1 | 97％ | 84％ |
As seen from the above table, when the consumption of potassium hydroxide is very few, owing to can not provide stronger alkaline environment, raw material reaction is incomplete, causes yield too low, when potassium hydroxide consumption is too much, alkalescence is excessively strong, and the side reaction of system is difficult to suppress, and has occurred more by product, and add the burden of acidifying, therefore select 5.8:1 to use as optimal conditions.
The ratio Selecting research of embodiment 3, solvent dimethyl sulfoxide (DMSO) (B) and m-difluorobenzene (A), related data gathers as following table
| B/A mol ratio | Product purity | Yield |
| 6:1 | 84％ | 66％ |
| 8:1 | 92％ | 67％ |
| 10:1 | 97％ | 80％ |
| 11：1 | 98.5％ | 85％ |
| 13:1 | 98％ | 84％ |
As seen from the above table, quantity of solvent also has important impact to reaction, and quantity of solvent is very few, can not have larger dispersiveness, cause byproduct of reaction to produce more, quantity of solvent is too much, reaction is not too significantly benefited, therefore chooses the best proportion of 11:1 as dimethyl sulfoxide (DMSO) and m-difluorobenzene.
Embodiment 4, usage ratio research about dimethyl sulfoxide (DMSO) (B) and water (A), data are as shown in the table:
| B/A mass ratio | Product purity | Yield |
| 99:1 | 30％ | 10％ |
| 49:1 | 35％ | 18％ |
| 19:1 | 57％ | 43％ |
| 9:1 | 75％ | 66％ |
| 4:1 | 98.5 | 85％ |
| 1:1 | 98％ | 55％ |
As seen from the above table, adjustment solvent ratios on reaction impact greatly, this is mainly because reaction is inhomogeneous reaction, water is on the one hand as solvent, also participate in hydrolysis reaction as reactant on the other hand, and dimethyl sulfoxide (DMSO) is as the solvent had organism and aqueous phase compared with strong solubility, it is the prerequisite that reaction occurs.Finally we select 4:1 as the best proportion of dimethyl sulfoxide (DMSO) and water
Embodiment 5, thermal creep stress when dripping about m-difluorobenzene, correlative study data are as shown in the table:
| Dropping temperature | Product purity | Yield |
| 50 degree | 97％ | 73％ |
| 100 degree | 97％ | 74％ |
| 128 degree | 98％ | 85％ |
| 135 degree | 98％ | 76％ |
As seen from the above table, dropping temperature is too low, reacts abundant with regard to temperature rising reflux not, raw material has little time condensation, run off more, dropping temperature is too high also to be existed raw material and has little time reaction and just gasify the phenomenon of running away, and therefore selection 128 degree is as the optimum temps of dropping m-difluorobenzene.
Embodiment 6, for research temperature controlled when reacting completely, by reaction Raw in control obtain following data:
| Temperature of reaction | Starting material left | Yield | Reaction times |
| 132 | 10％ | 77％ | 2h |
| 138 | 5％ | 80％ | 3h |
| 145 | 0.3％ | 85.3％ | 5h |
| 148 | 0.2％ | 85.1％ | 6h |
As seen from the above table, this reaction response completely temperature is about 145 degree, and the reaction times is at 4-6h.We choose 145 degree, the optimal conditions that reaction 5h terminates as reaction.
Embodiment 7, about acidifying index completely, we have done series of contrast, and result gathers as following table:
| PH | Purity | Yield |
| PH＝1 | 95％ | 78％ |
| PH＝2 | 96％ | 80％ |
| PH＝4 | 98％ | 85％ |
| PH＝7 | 98％ | 82％ |
| PH＝9 | 97％ | 78％ |
As seen from the above table, too low with the PH of hcl acidifying, product under strongly acidic conditions solubization strengthens, cause yield too low, the incomplete words product of acidifying runs off in a salt form from water, and yield also can be caused too low, therefore selects PH=4 as acidifying optimal conditions completely.
Embodiment 8, consumption (mass volume ratio of m-difluorobenzene and ether) about extraction solvent, done simultaneous test, result gathers as follows:
| Quantity of solvent | Yield |
| 1：5 | 72％ |
| 1:10 | 78％ |
| 1:14 | 85％ |
As seen from the above table, consider and choose the optimum amount of 1:14 as solvent ether.
To sum up, have report in the reaction document at home and abroad that m fluorophenol is produced in m-difluorobenzene hydrolysis, the problem generally reflected is exactly: reaction yield is low, and by product is many, separation difficulty more.Its highest yield can only be accomplished less than 60 percent, and circulation ratio extreme difference.This programme is thought, always makes its anhydrous and oxygen-free to reach the object optimizing reaction as much as possible in generic reaction in the past for the use of dimethyl sulfoxide (DMSO), and this so does also really effectively for great majority reaction.But the hydrolysis of m-difluorobenzene is to solvent, and temperature of reaction, base strength has special requirement, and this reaction changes polarity and the dispersiveness of solvent with a kind of distinct thinking.Adding of water not only makes organic phase and inorganic phase obtain suitable transfer rate, prevent the side reaction produced due to strong alkaline condition, simultaneously, water exists as reactant, the process of reaction itself is made to there occurs change, become smooth steady, the process for reaction has had great improvement, therefore well improves selectivity and the yield of reaction.
Foregoing description only proposes, not as the single restricted condition to its technical scheme itself as the enforceable technical scheme of the present invention.
Claims (2)
1. a preparation method for m fluorophenol, is characterized in that: the method comprises the steps:
A, in the reactor containing ptfe plastic lining, add potassium hydroxide, dimethyl sulfoxide (DMSO) and water, be warming up to 120-140 degree, drip m-difluorobenzene, in dropping process, make unreacted m-difluorobenzene return in reaction substrate by condenser;
Wherein, the mol ratio of m-difluorobenzene and potassium hydroxide is 1:5.8; The mass ratio of m-difluorobenzene and dimethyl sulfoxide (DMSO) is 1:11; The mass ratio of water and dimethyl sulfoxide (DMSO) is 1:4; The temperature dripping reaction system during m-difluorobenzene is 128 degree;
After B, m-difluorobenzene dropwise, back flow reaction to liquid temperature reaches 140-150 degree, after reaction 4-6h, be cooled to 26-34 degree, decompression 3-6KPa steams solvent, steam to liquid temperature 140-160 degree, reaction solution is poured in frozen water, regulate PH=3-5, use extracted with diethyl ether product, steam solvent, obtain m fluorophenol product;
Wherein, back flow reaction to liquid temperature reaches 145 degree, and the reaction times is 5h, is cooled to 30 degree, regulates PH=4 after steaming solvent with concentrated hydrochloric acid after reaction terminates; The mass volume ratio of m-difluorobenzene and extraction agent ether is 1:14.
2. a preparation method for m fluorophenol, is characterized in that: the method comprises the steps, the volume wherein related to or volume, all adopts mL to be unit; The quality related to or weight, all adopt g to be unit;
A, on the four-hole bottle of 10000 volume parts, install mechanical stirring, constant pressure funnel, prolong and thermometer additional, and logical argon gas is protected, then potassium hydroxide 1305 weight part, dimethyl sulfoxide (DMSO) 5500 weight part and water 1300 weight part is added, be warming up to 130 degree, start to drip m-difluorobenzene, add the m-difluorobenzene of 463 weight parts in 40min, make unreacted m-difluorobenzene turn back in reaction substrate by condenser by prolong;
After B, m-difluorobenzene dropwise, back flow reaction to liquid temperature reaches 145 degree, stops heating, logical argon gas is cooled to 30 degree, decompression 5KPa steams solvent, and steaming to liquid temperature is 150 degree, pours in the frozen water of 9000 weight parts, PH=4 is acidified to the concentrated hydrochloric acid of 1700 parts by volume, stir 30min, divide three extractions with the ether of 6000 parts by volume, through dried over sodium sulfate, filter, drain, recycling design, decompression precipitation, obtain crude product 386.4 weight part.
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| CN112479825A (en) * | 2020-11-26 | 2021-03-12 | 浙江中欣氟材股份有限公司 | Synthetic method of compound containing fluorophenol structure |
| CN115260010B (en) * | 2021-04-29 | 2023-11-24 | 新岸诺亚（北京）催化科技有限公司 | Method for preparing m-fluorophenol from 2, 6-difluorobenzonitrile |
| CN115260009B (en) * | 2021-04-29 | 2023-11-24 | 新岸诺亚（北京）催化科技有限公司 | Preparation method of m-fluorophenol |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4940821A (en) * | 1989-03-20 | 1990-07-10 | The Dow Chemical Company | Preparation of fluorophenols |
| SU1759829A1 (en) * | 1990-09-04 | 1992-09-07 | Пермский филиал научно-производственного объединения "Государственный институт прикладной химии" | Method of producing monofluorophenols |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09136853A (en) * | 1995-11-13 | 1997-05-27 | Kanto Denka Kogyo Co Ltd | Production of fluorophenols |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4940821A (en) * | 1989-03-20 | 1990-07-10 | The Dow Chemical Company | Preparation of fluorophenols |
| SU1759829A1 (en) * | 1990-09-04 | 1992-09-07 | Пермский филиал научно-производственного объединения "Государственный институт прикладной химии" | Method of producing monofluorophenols |
Non-Patent Citations (1)
| Title |
|---|
| Copper MOF: scope and limitation in catalytic hydroxylation and nitration of aryl halides;S. Priyadarshini et al.;《Tetrahedron》;20130529;第 69卷;6409-6414 * |
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Effective date of registration: 20190809 Address after: 100022 Beijing Chaoyang District Shuangyuan Nanli District 11 Building 3 316 Patentee after: New shores Noah (Beijing) Catalytic Technology Co., Ltd. Address before: 100022, Beijing, Chaoyang District East Third Ring Road, building 63, R & F Center, room 701 Patentee before: XIN'AN NUOYA (BEIJING) CHEMICAL ENGINEERING TECHNOLOGY CO., LTD. |
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Application publication date: 20141112 Assignee: Xinqi times (Datong) new material Co.,Ltd. Assignor: Xin-An Nuoya (Beijing) Catalytic Technology Co.,Ltd. Contract record no.: X2020990000670 Denomination of invention: A preparation method of m-fluorophenol Granted publication date: 20151209 License type: Common License Record date: 20201211 |