CN105152878A - Method for preparing 4-ethoxy-2,3-difluorophenol by one-pot method - Google Patents
Method for preparing 4-ethoxy-2,3-difluorophenol by one-pot method Download PDFInfo
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- CN105152878A CN105152878A CN201510423679.XA CN201510423679A CN105152878A CN 105152878 A CN105152878 A CN 105152878A CN 201510423679 A CN201510423679 A CN 201510423679A CN 105152878 A CN105152878 A CN 105152878A
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- oxyethyl group
- difluorophenol
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- grignard reagent
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
- C07C41/01—Preparation of ethers
- C07C41/18—Preparation of ethers by reactions not forming ether-oxygen bonds
- C07C41/26—Preparation of ethers by reactions not forming ether-oxygen bonds by introduction of hydroxy or O-metal groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F5/00—Compounds containing elements of Groups 3 or 13 of the Periodic System
- C07F5/02—Boron compounds
- C07F5/025—Boronic and borinic acid compounds
Abstract
The invention discloses a method for preparing 4-ethoxy-2,3-difluorophenol by a one-pot method and relates to the technical field of organic synthesis. The method comprises the steps of enabling 4-ethoxy-2,3-difluorobromobenzene, which serves as a raw material, to react with magnesium pieces in the presence of iodine which serves as an initiator so as to prepare a Grignard reagent, then, enabling the Grignard reagent to be subjected to borating reaction with trimethyl borate, carrying out hydrochloric acid hydrolysis so as to prepare 4-ethoxy-2,3-difluoro phenylboric acid, then, oxidizing 4-ethoxy-2,3-difluoro phenylboric acid with hydrogen peroxide so as to prepare a 4-ethoxy-2,3-difluorophenol crude product, and finally, carrying out desalting purification, thereby preparing a 4-ethoxy-2,3-difluorophenol pure product. According to the method, the prepared product is high in yield and purity, solvents are easily recovered and reused, the reaction conditions are mild, the coefficient of safety is relatively high, the operability is high, the process is simple, the volume of wastewater is small, and the product fully meets the requirements of use as liquid-crystal intermediates and drug intermediates, so that the method is applicable to industrial production.
Description
Technical field:
The present invention relates to technical field of organic synthesis, be specifically related to a kind of method that one kettle way prepares 4-oxyethyl group-2,3-difluorophenol.
Background technology:
4-oxyethyl group-2,3-difluorophenol is a kind of conventional industrial chemicals, makes the negative liquid crystal material of the display screen such as televisor, mobile phone for liquid crystal intermediates.Lcd technology is one of main display mode of flat display field, and it is widely used at various display terminal.Liquid crystal material is the crucial photoelectron material of liquid-crystal display, and the quality of its performance determines the quality of liquid-crystal display.Therefore along with the development of lcd technology, more and more urgent to the requirement of researching and developing novel liquid crystal material.4-oxyethyl group-2, the synthetic method of 3-difluorophenol is more, but there is the large and feature that yield is not high of synthesis technique complexity, workload, in order to be more suitable for suitability for industrialized production, our company have developed one and utilizes one kettle way to prepare the method for 4-oxyethyl group-2,3-difluorophenol.
Summary of the invention:
Technical problem to be solved by this invention is to provide a kind of simple to operate, method that yield is high one kettle way prepares 4-oxyethyl group-2,3-difluorophenol.
Technical problem to be solved by this invention adopts following technical scheme to realize:
A kind of one kettle way prepares the method for 4-oxyethyl group-2,3-difluorophenol, with 4-oxyethyl group-2,3-difluoro bromobenzene is raw material, iodine is initiator, reacts obtained grignard reagent, then react with trimethyl borate generation boration with magnesium sheet, obtained 4-oxyethyl group-2 after hydrochloric acid hydrolysis, 3-difluorobenzene boric acid, then obtain 4-oxyethyl group-2,3-difluorophenol crude product through hydrogen peroxide oxidation, finally by 4-oxyethyl group-2,3-difluorophenol sterling obtained after desalting and purifying.
A kind of one kettle way prepares the method for 4-oxyethyl group-2,3-difluorophenol, comprises the following steps:
(1) preparation of Grignard reagent: under nitrogen protection, first magnesium sheet and tetrahydrofuran (THF) are dropped in reactor, add iodine again, mixing control temperature is at 0 ~ 60 DEG C, then start the mixing solutions dripping 4-oxyethyl group-2,3-difluoro bromobenzene and tetrahydrofuran (THF), dropwise rear insulation reaction, stopped reaction after raw material reaction is complete, obtains Grignard reagent;
(2) boration reaction: boric acid ester and tetrahydrofuran (THF) are dropped in reactor, logical nitrogen protection, be cooled to-40 ~ 10 DEG C to start to drip above-mentioned obtained Grignard reagent, after dropwising, be warming up to 0 ~ 20 DEG C of reaction, after raw material reaction is complete, adds the hydrochloric acid soln of mass concentration 10%, stir, stratification, then organic layer is merged after extraction, concentrated, obtained 4-oxyethyl group-2,3-difluorobenzene boric acid;
(3) oxidizing reaction: by above-mentioned obtained 4-oxyethyl group-2,3-difluorobenzene boric acid drops in reactor, and add the methyl alcohol of 3-5 times amount, stirring and evenly mixing, temperature control to 10 ~ 40 DEG C, then drip the hydrogen peroxide of mass concentration 30-50%, concentrating under reduced pressure after raw material reaction is complete, residuum adds water precipitation solid, centrifugal 4-oxyethyl group-2,3-difluorophenol crude product;
(4) desalting and purifying: by above-mentioned obtained 4-oxyethyl group-2,3-difluorophenol crude product drops in reactor, add water mixing, then a small amount of sodium sulfite solution is added to starch potassium iodide paper nondiscoloration, centrifugal, in gained solid, add toluene dissolve back and heat up in a steamer, finally by crystallisation by cooling, centrifugal the fluorine-based phenol product of 4-oxyethyl group-2,3-bis-.
Dropping temperature preferably 10 ~ 30 DEG C in described step (1), insulation reaction temperature controls at 30 ~ 40 DEG C.
The dropping temperature of Grignard reagent preferably-40 ~-20 DEG C in described step (2).
The dropping temperature preferably 10 ~ 20 DEG C of hydrogen peroxide in described step (3).
The invention has the beneficial effects as follows: the present invention is with raw material 4-oxyethyl group-2,3-difluoro bromobenzene is raw material, obtained product yield and purity high, solvent is easy to recovery of applied, and reaction conditions is gentle, safety coefficient is higher, workable, technique is simple, and waste water is few, meet the service requirements as liquid crystal intermediates and pharmaceutical intermediate completely, be suitable for suitability for industrialized production.
Embodiment:
The technique means realized to make the present invention, creation characteristic, reaching object and effect is easy to understand, below in conjunction with specific embodiment, setting forth the present invention further.
Embodiment 1
(1) preparation of grignard reagent: first in 1000mL there-necked flask, add 600mLTHF and 200g4-oxyethyl group-2,3-difluoro bromobenzene stirs and makes solution, for subsequent use, then in 2L there-necked flask, 25g magnesium is added, 20mLTHF, 1g iodine, by the 4-oxyethyl group-2 prepared, the THF solution 20mL of 3-difluoro bromobenzene instills, add thermal initiation after, at 10-20 DEG C, drip the THF solution of residue 4-oxyethyl group-2,3-difluoro bromobenzene, at 30-35 DEG C of insulated and stirred 1h after dripping, with liquid nitrogen reaction flask is cooled to less than-30 DEG C for subsequent use;
(2) boration reaction: in above-mentioned form liquid, slowly drips the 600mLTHF solution of 110g trimethyl borate, and the process that drips maintains less than-30 DEG C, drip off rear stirring and naturally rise to room temperature, drip 400mL10% hydrochloric acid, backflow 1h, after distilling out THF, add 500mL cold water, stir 30min, cooling, crystallization, separation, obtain 153g4-oxyethyl group-2,3-difluorobenzene boric acid, yield is 90%, HPLC area normalization purity is 94.7%;
(3) oxidizing reaction: add 50g4-oxyethyl group-2 in 1L there-necked flask, 3-difluorobenzene boric acid, methyl alcohol 200mL, stirring and dissolving, drips 50% hydrogen peroxide 30mL at 15 DEG C, drip after finishing stirring 30min, be warming up to 50 DEG C of decompression precipitations, add 200g water, cooling is rear, centrifugal obtains 4-oxyethyl group-2,3-difluorophenol crude product, HPLC area normalization purity is 95.5%;
(4) desalting and purifying: add above-mentioned gained 4-oxyethyl group-2 in 1L there-necked flask, 3-difluorophenol crude product, the 100mL that adds water mixes, add a small amount of sodium sulfite solution to starch potassium iodide paper nondiscoloration, the dissolving of 200mL toluene, precipitation, cooling, crystallization, centrifugal, dry 32g4-oxyethyl group-2 is added again after centrifugal, the fluorine-based phenol product of 3-bis-, yield is 74%, HPLC area normalization purity is 99.7%.
Embodiment 2
(1) preparation of grignard reagent: first in 5000mL there-necked flask, adds the stirring of 3000mLTHF and 1000g4-oxyethyl group-2,3 difluoro bromobenzene and makes solution, for subsequent use.Then in 5L there-necked flask, 125g magnesium is added, 100mLTHF, 3g iodine, by the 4-oxyethyl group-2 prepared, the THF solution 100mL of 3-difluoro bromobenzene instills, add thermal initiation after, at 10-20 DEG C, drip the THF solution of residue 4-oxyethyl group-2,3 difluoro bromobenzene, at 30-35 DEG C of insulated and stirred 1h after dripping, with liquid nitrogen reaction flask is cooled to less than-30 DEG C for subsequent use;
(2) boration reaction: in above-mentioned form liquid, slowly drips the 3000mLTHF solution of 550g trimethyl borate, and the process that drips maintains less than-30 DEG C, drip off rear stirring and naturally rise to room temperature, drip 2000mL10% hydrochloric acid, backflow 1h, after distilling out THF, add 1000mL cold water, stir 30min, cooling, crystallization, separation, obtain 748g4-oxyethyl group-2,3-difluorobenzene boric acid, yield is 88%, HPLC area normalization purity is 95.2%;
(3) oxidizing reaction: add 250g4-oxyethyl group-2 in 5L there-necked flask, 3-difluorobenzene boric acid, methyl alcohol 1000mL, stirring and dissolving, drips 50% hydrogen peroxide 150mL at 20 DEG C, drip after finishing stirring 30min, be warming up to 50 DEG C of decompression precipitations, add 800g water, cooling is rear, centrifugal obtains 4-oxyethyl group-2,3-difluorophenol crude product, HPLC area normalization purity is 95.6%;
(4) desalting and purifying: add above-mentioned gained 4-oxyethyl group-2 in 5L there-necked flask, 3-difluorophenol crude product, the 500mL that adds water mixes, add a small amount of sodium sulfite solution to starch potassium iodide paper nondiscoloration, the dissolving of 1000mL toluene, precipitation, cooling, crystallization, centrifugal, dry 161g4-oxyethyl group-2 is added again after centrifugal, the fluorine-based phenol product of 3-bis-, yield is 75%, HPLC area normalization purity is 99.6%.
Embodiment 3
(1) preparation of grignard reagent: first in 1000L enamel reaction still, adds the stirring of 600LTHF and 200kg4-oxyethyl group-2,3-difluoro bromobenzene and makes solution, for subsequent use.Then in 3000L enamel reaction still, 25kg magnesium is added, 20LTHF, 100g iodine particle, by the 4-oxyethyl group-2 prepared, the THF solution 20L of 3-difluoro bromobenzene instills, add thermal initiation after, at 10-20 DEG C, drip the THF solution of residue 4-oxyethyl group-2,3-difluoro bromobenzene, at 30-35 DEG C of insulated and stirred 1h after dripping, with liquid nitrogen reaction flask is cooled to less than-30 DEG C for subsequent use;
(2) boration reaction: in above-mentioned form liquid, the 600LTHF solution of slow dropping 110kg trimethyl borate, the process that drips maintains less than-30 DEG C, drips off rear stirring and naturally rises to room temperature, drip 400L10% hydrochloric acid, backflow 1h, after distilling out THF, adds 500L cold water, stir 30min, cooling, crystallization, separation, obtain 154kg4-oxyethyl group-2,3-difluorobenzene boric acid, yield is 91%, HPLC area normalization purity is 95.1%;
(3) oxidizing reaction: add 50kg4-oxyethyl group-2 in 500L enamel reaction still, 3-difluorobenzene boric acid, methyl alcohol 200L, 30% liquid caustic soda 80L, stirring and dissolving, drip 50% hydrogen peroxide 30L at 10 DEG C, drip after finishing stirring 30min, be warming up to 50 DEG C of decompression precipitations, add 200kg water, cooling is rear, centrifugal obtains 4-oxyethyl group-2,3-difluorophenol crude product, and HPLC area normalization purity is 94.5%;
(4) desalting and purifying: add above-mentioned gained 4-oxyethyl group-2 in 500L enamel reaction still, 3-difluorophenol crude product, the 100L that adds water mixes, add a small amount of sodium sulfite solution to starch potassium iodide paper nondiscoloration, the dissolving of 200L toluene, precipitation, cooling, crystallization, centrifugal, dry 33kg4-oxyethyl group-2 is added again after centrifugal, the fluorine-based phenol product of 3-bis-, yield is 77%, HPLC area normalization purity is 99.5%.
Embodiment 4
(1) preparation of grignard reagent: first in 2000L enamel reaction still, adds the stirring of 1200LTHF and 400kg4-oxyethyl group-2,3-difluoro bromobenzene and makes solution, for subsequent use.Then in 5000L enamel reaction still, 50kg magnesium is added, 40LTHF, 200g iodine particle, by the 4-oxyethyl group-2 prepared, the THF solution 40L of 3-difluoro bromobenzene instills, add thermal initiation after, at 10-20 DEG C, drip the THF solution of residue 4-oxyethyl group-2,3-difluoro bromobenzene, at 30-35 DEG C of insulated and stirred 1h after dripping, with liquid nitrogen reaction flask is cooled to less than-30 DEG C for subsequent use;
(2) boration reaction: in above-mentioned form liquid, the 1200LTHF solution of slow dropping 220kg trimethyl borate, the process that drips maintains less than-30 DEG C, drips off rear stirring and naturally rises to room temperature, drip 800 liter of 10% hydrochloric acid, backflow 1h, after distilling out THF, adds 1000L cold water, stir 30min, cooling, crystallization, separation, obtain 302kg4-oxyethyl group-2,3-difluorobenzene boric acid, yield is 89%, HPLC area normalization purity is 95.2%;
(3) oxidizing reaction: add 100kg4-oxyethyl group-2 in 1000L enamel reaction still, 3-difluorobenzene boric acid, methyl alcohol 400L, stirring and dissolving, drips 50% hydrogen peroxide 60L at 15 DEG C, drip after finishing stirring 30min, be warming up to 50 DEG C of decompression precipitations, add 400kg water, cooling is rear, centrifugal obtains 4-oxyethyl group-2,3-difluorophenol crude product, HPLC area normalization purity is 95.9%;
(4) desalting and purifying: add above-mentioned gained 4-oxyethyl group-2 in 1000L enamel reaction still, 3-difluorophenol crude product, the 200L that adds water mixes, add a small amount of sodium sulfite solution to starch potassium iodide paper nondiscoloration, the dissolving of 400L toluene, precipitation, cooling, crystallization, centrifugal, dry 65kg4-oxyethyl group-2 is added again after centrifugal, the fluorine-based phenol product of 3-bis-, yield is 75%, HPLC area normalization purity is 99.8%.
More than show and describe ultimate principle of the present invention and principal character and advantage of the present invention.The technician of the industry should understand; the present invention is not restricted to the described embodiments; what describe in above-described embodiment and specification sheets just illustrates principle of the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.Application claims protection domain is defined by appending claims and equivalent thereof.
Claims (4)
1. an one kettle way prepares the method for 4-oxyethyl group-2,3-difluorophenol, it is characterized in that: with 4-oxyethyl group-2,3-difluoro bromobenzene is raw material, iodine is initiator, reacts obtained grignard reagent, then react with trimethyl borate generation boration with magnesium sheet, obtained 4-oxyethyl group-2 after hydrochloric acid hydrolysis, 3-difluorobenzene boric acid, then obtain 4-oxyethyl group-2,3-difluorophenol crude product through hydrogen peroxide oxidation, finally by 4-oxyethyl group-2,3-difluorophenol sterling obtained after desalting and purifying.
2. an one kettle way prepares the method for 4-oxyethyl group-2,3-difluorophenol, it is characterized in that, comprises the following steps:
(1) preparation of Grignard reagent: under nitrogen protection, first magnesium sheet and tetrahydrofuran (THF) are dropped in reactor, add iodine again, mixing control temperature is at 0 ~ 60 DEG C, then start the mixing solutions dripping 4-oxyethyl group-2,3-difluoro bromobenzene and tetrahydrofuran (THF), dropwise rear insulation reaction, stopped reaction after raw material reaction is complete, obtains Grignard reagent;
(2) boration reaction: boric acid ester and tetrahydrofuran (THF) are dropped in reactor, logical nitrogen protection, be cooled to-40 ~ 10 DEG C to start to drip above-mentioned obtained Grignard reagent, after dropwising, be warming up to 0 ~ 20 DEG C of reaction, after raw material reaction is complete, adds the hydrochloric acid soln of mass concentration 10%, stir, stratification, then organic layer is merged after extraction, concentrated, obtained 4-oxyethyl group-2,3-difluorobenzene boric acid;
(3) oxidizing reaction: by above-mentioned obtained 4-oxyethyl group-2,3-difluorobenzene boric acid drops in reactor, and add the methyl alcohol of 3-5 times amount, stirring and evenly mixing, temperature control to 10 ~ 40 DEG C, then drip the hydrogen peroxide of mass concentration 30-50%, concentrating under reduced pressure after raw material reaction is complete, residuum adds water precipitation solid, centrifugal 4-oxyethyl group-2,3-difluorophenol crude product;
(4) desalting and purifying: by above-mentioned obtained 4-oxyethyl group-2,3-difluorophenol crude product drops in reactor, add water mixing, then a small amount of sodium sulfite solution is added to starch potassium iodide paper nondiscoloration, centrifugal, in gained solid, add toluene dissolve back and heat up in a steamer, finally by crystallisation by cooling, centrifugal the fluorine-based phenol product of 4-oxyethyl group-2,3-bis-.
3. one kettle way according to claim 2 prepares the method for 4-oxyethyl group-2,3-difluorophenol, it is characterized in that: dropping temperature preferably 10 ~ 30 DEG C in described step (1), insulation reaction temperature controls at 30 ~ 40 DEG C.
4. one kettle way according to claim 2 prepares the method for 4-oxyethyl group-2,3-difluorophenol, it is characterized in that: the dropping temperature of Grignard reagent preferably-40 ~-20 DEG C in described step (2).
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114230540A (en) * | 2022-01-06 | 2022-03-25 | 西安爱德克美新材料有限公司 | Method for synthesizing alpha-BPDA |
| CN117402041A (en) * | 2023-10-16 | 2024-01-16 | 浙江吉泰新材料股份有限公司 | Synthesis method of 4-ethoxy-2, 3-difluorophenol |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1847210A (en) * | 2005-04-11 | 2006-10-18 | 临海市永太化工有限公司 | Process of producing pentafluorophenol |
| CN101265269A (en) * | 2008-03-21 | 2008-09-17 | 浙江工业大学 | Method for preparing pentafluorophenyl boric acid |
| CN101445431A (en) * | 2008-12-30 | 2009-06-03 | 衢州康鹏化学有限公司 | Method for preparing fluorophenol |
-
2015
- 2015-07-15 CN CN201510423679.XA patent/CN105152878A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1847210A (en) * | 2005-04-11 | 2006-10-18 | 临海市永太化工有限公司 | Process of producing pentafluorophenol |
| CN101265269A (en) * | 2008-03-21 | 2008-09-17 | 浙江工业大学 | Method for preparing pentafluorophenyl boric acid |
| CN101445431A (en) * | 2008-12-30 | 2009-06-03 | 衢州康鹏化学有限公司 | Method for preparing fluorophenol |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114230540A (en) * | 2022-01-06 | 2022-03-25 | 西安爱德克美新材料有限公司 | Method for synthesizing alpha-BPDA |
| CN117402041A (en) * | 2023-10-16 | 2024-01-16 | 浙江吉泰新材料股份有限公司 | Synthesis method of 4-ethoxy-2, 3-difluorophenol |
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Application publication date: 20151216 |