CN108558618A - A method of preparing 2,3- difluorophenols - Google Patents
A method of preparing 2,3- difluorophenols Download PDFInfo
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- CN108558618A CN108558618A CN201810522883.0A CN201810522883A CN108558618A CN 108558618 A CN108558618 A CN 108558618A CN 201810522883 A CN201810522883 A CN 201810522883A CN 108558618 A CN108558618 A CN 108558618A
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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
- C07C41/16—Preparation of ethers by reaction of esters of mineral or organic acids with hydroxy or O-metal groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
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- 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
- C07C37/055—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 the substituted group being bound to oxygen, e.g. ether group
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Abstract
2 are prepared the present invention relates to a kind of, the method of 3 difluorophenols, with 1,2,3 trifluoro-benzenes are raw material, alkoxylate and dealkylation reaction by solid super strong base catalysis prepare 2,3 difluorophenols, and synthetic route is short, technological operation is simple, without special equipment, yield is up to 94.8% or more, has good industrial prospect.
Description
Technical field
The invention belongs to field of fine chemical more particularly to a kind of methods preparing 2,3- difluorophenols.
Background technology
Fluorine atom is introduced in aromatic compound can dramatically increase the stability of compound, while it is fat-soluble also to improve its
And hydrophobicity, promote it to absorb and transmit in vivo, physiological action is made to change, so many fluorine-containing medicines and pesticide
Opposite in performance to have the characteristics that dosage is few, toxicity is low, drug effect is high, metabolic capability is strong, this makes it in new medicine, pesticide species
Middle proportion is higher and higher.In addition the difference such as fluoride dye, fluorine-containing surfactant, fluorine-containing textile finishing agent, fluoro-containing coating
High added value, promising kind as respective field of fine chemical.Just because of the particularity of carbon-fluorine bond, You Jifen
Introducing fluorine atom in son especially aromatic hydrocarbons is particularly important but also challenges heavy.
Realize that fluorination reaction is carbon-fluorine bond structure research field recent years using the direct activation of aryl C-H bond
One hot spot, due to having which obviate the use of pre- functionalized aryl derivatives, Atom economy is high, substrate spectrum is wide
The advantages that.Although having there is correlative study to report in succession at present, including works such as utilization nitrogen heterocyclic ring, amide, carbonyl oxime ethers
For the ortho selectivity C-H bond fluoride system of homing device control, but available substrate is still confined to nitrogen heterocyclic ring, benzene first
Acid, benzylamine and aryl carbonyl compound.
2,3- difluorophenols (TFBA), English name 2,3-DifluoroPhenol, molecular formula C6H4F2O, molecular weight
130.09, it is white crystalline body, 34-36 DEG C of fusing point.It is used to synthesize liquid crystal material, antimycotic agent etc. more, be additionally operable to synthesize
Dyestuff, plastics and rubber additive are important medicine and pesticide intermediate.
There are following several synthetic methods at present：
(1) H for being 10% by 2,3- difluoros phenyl boric acid and mass fraction202It is reacted in diethyl ether solution, obtains TFBA：
Bis- fluoro- 2- alkoxyl anilines of (2) 3,4- are raw material, deamination and alkyl：
(3) 2,3,4 one trifluoromethyl anilines, with sodium nitrite diazotising at room temperature, then hydrolyze to obtain difluorobenzene in sulfuric acid liquid
Phenol：
All there are the deficiencies such as reaction step is more, process is complicated, and yield is low, be not easy industrialized production in current preparation method.
Invention content
In view of the deficiencies of the prior art, the present invention provides a kind of method preparing 2,3- difluorophenols, which can be with
Brief step, shirtsleeve operation technique, higher yield, lower cost synthesize 2, the 3- Difluoro-5-Bromophenols of high-purity.
The technical solution of the use of the present invention is as follows：A kind of method preparing 2,3- difluorophenols, with 1,2,3- trifluoro-benzene
For raw material, reaction equation is as follows：
Include the following steps：
1) in the presence of solid super base, 3,4,5- trifluorobromobenzenes and alkylol are made to carry out alkoxy substitution reaction, instead
After answering, post-treated be directly entered of reaction mixture is reacted in next step：
2) in the presence of a lewis acid, 2,3-, bis- fluoro- 1- alkoxy benzenes carry out dealkylation, after reaction, instead
Mixture is answered to handle to obtain 2,3- difluorophenols.
Preferably, the alkylol described in step 1) is the alkylol of C1-C8, preferably methanol and ethyl alcohol；Alkylol with
The molar ratio of 1,2,3- trifluoro-benzenes is 1-10:1；
The solid super base is titanium dioxide zirconium base solid super base, specific preparation method：
Crystallization zirconium chloride wiring solution-forming is taken, pH value of solution=6-8, centrifugation are adjusted with the KOH of 1mol/L or NH3H2O
Separation is washed 4-5 times, then the sediment wiring solution-forming that will be obtained, addition graphene oxide solution, reflux digestion 12-72h, from
The heart detaches, and is dried overnight, and then puts the precipitate in and is gradually warming up to 400-700 DEG C in Muffle furnace, roasts 1-5h, and dioxy is made
Change zirconium；The zirconium dioxide of the above-mentioned preparations of 70wt%-90wt% and the modification component of 10wt%-30wt% are taken respectively, grind postposition
400-700 DEG C is warming up under N2 or atmosphere of inert gases in tube furnace, 1-5h is heat-treated, obtains solid super strong base catalysis
Agent.
The heat treatment condition is N2 or atmosphere of inert gases, and heat treatment temperature is 400-700 DEG C, heating rate 1-10
DEG C/min, heat treatment time 1-5h.
Wherein, the modification component is selected from least one of potassium hydroxide, potassium nitrate, potassium fluoride or potassium carbonate.
Further, the reaction of step 1) carries out under nitrogen atmosphere, and reaction temperature is 50-100 DEG C, reaction time 10-
20 hours, substantially without polyalkoxylated product in reaction process；
Preferably, the post processing mode of step 1) is, after reaction.A certain amount of moisture liquid is added, acetic acid second is used in combination
Ester aqueous phase extracted merges organic phase and acetic acid ethyl acetate extract, distills water washing, anhydrous sodium sulfate drying, solvent evaporated.
Lewis acid described in step 2) is alchlor, boron trifluoride ether or iron chloride, preferably, described
Lewis acid is iron chloride；The molar ratio of lewis acid and 1,2,3- trifluoro-benzenes is 1:0.8-1.2；
In step 2), the reaction carries out preferably in reaction dissolvent, and the organic solvent of selection is ether solvent or alcohol
Class solvent, preferably methanol, ethyl alcohol, ether and tetrahydrofuran.
The reaction temperature of step 2) is 30-50 DEG C, and the reaction time is 2-10 hours.
The post-processing approach of step 2) is after reaction, dilute alkaline soln to be added, and liquid separation obtains organic phase and water phase, uses
Ethyl acetate aqueous phase extracted merges organic phase and acetic acid ethyl acetate extract, saturated common salt water washing, solvent evaporated, vacuum distillation
Up to 2,3- difluorophenols.
The advantageous effect of the method for the present invention is：
With 1,2,3- trifluoro-benzene for raw material, alkoxylate and dealkylation reaction by solid super strong base catalysis prepare 2,
3- difluorophenols, synthetic route is short, and technological operation is simple, is not necessarily to special equipment, and 94.8% or more high income has good work
Industry foreground.
Specific implementation mode
Below in conjunction with technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described
Embodiment is only a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, ability adds
Enter the every other embodiment that domain those of ordinary skill is obtained without making creative work, belongs to this hair
The range of bright protection.
【Embodiment 1】
It weighs 7.012 grams of ZrCl45H2O to be dissolved in 100mL water, wiring solution-forming；Side is stirred, while will by constant pressure funnel
The KOH of 1mol/L is added drop-wise in solution, until the pH of solution is 6-8, is stopped being added dropwise, is continued to stir 3h；It centrifuges, washing 4~5
It is secondary, sediment is redissolved in 60mL water wiring solution-formings；The graphene oxide solution of a concentration of 2g/L of 60mL is added dropwise, is risen in oil bath
To 103 DEG C, condensing reflux for 24 hours, centrifuges, is dried overnight, in roaster, 550 are risen to 5 DEG C/min by room temperature temperature
DEG C, and 3h is kept at 550 DEG C, obtain ZrO2；80wt%ZrO2 and 20wt%KOH are taken, is placed in mortar, water is added to grind, is dried,
It finally places it in tube furnace after being warming up to 550 DEG C under N2 atmosphere and is heat-treated 3h, it is solid to obtain 20% potassium doped zirconia
Body super basic catalyst.
【Embodiment 2】
It weighs 7.012 grams of ZrCl45H2O to be dissolved in 100mL water, wiring solution-forming；Side is stirred, while will by constant pressure funnel
The KOH of 1mol/L is added drop-wise in solution, until the pH of solution is 6-8, is stopped being added dropwise, is continued to stir 3h；It centrifuges, washing 4~5
It is secondary, sediment is redissolved in 60mL water wiring solution-formings；The graphene oxide solution of a concentration of 2g/L of 60mL, 180 DEG C of crystalline substances are added dropwise
Change for 24 hours, centrifuge, be dried overnight, in roaster, rises to 550 DEG C by room temperature with 5 DEG C/min, and keep at 550 DEG C
3h obtains ZrO2；80wt%ZrO2 and 20wt%KOH are taken, is placed in mortar, water is added to grind, dries, finally places it in tubular type
It is heat-treated 3h after being warming up to 550 DEG C under N2 atmosphere in stove, obtains 20% potassium doped zirconia solid super basic catalyst.
【Embodiment 3】
It weighs 7.012 grams of ZrCl45H2O to be dissolved in 100mL water, wiring solution-forming；Side is stirred, while will by constant pressure funnel
The KOH of 1mol/L is added drop-wise in solution, until the pH of solution is 6-8, is stopped being added dropwise, is continued to stir 3h；It centrifuges, washing 4~5
It is secondary, sediment is redissolved in 60mL water wiring solution-formings；The graphene oxide solution of a concentration of 2g/L of 60mL is added dropwise, is risen in oil bath
To 103 DEG C, condensing reflux for 24 hours, centrifuges, is dried overnight, in roaster, 550 are risen to 5 DEG C/min by room temperature temperature
DEG C, and 3h is kept at 550 DEG C, obtain ZrO2；90wt%ZrO2 and 10wt%KOH are taken, is placed in mortar, water is added to grind, is dried,
It finally places it in tube furnace after being warming up to 550 DEG C under N2 atmosphere and is heat-treated 3h, it is solid to obtain 10% potassium doped zirconia
Body super basic catalyst.
【Embodiment 4】
1) it is added in the reactor prepared by 0.1mol1,2,3- trifluoro-benzenes, 0.2mol ethyl alcohol and 0.05mol embodiments 1
20% potassium doped zirconia solid super basic catalyst is warming up to 50 DEG C, reacts 10 hours, and gas-chromatography tracks reaction process,
It waits for after reaction, 30mL distilled water being added, 20mL ethyl acetate aqueous phase extracteds are used in combination in liquid separation, merge organic phase and acetic acid second
Ester extract liquor distills water washing, anhydrous sodium sulfate drying with 10ML, and solvent evaporated obtains intermediate product.
2) step 1) is obtained into intermediate product and 20mL tetrahydrofurans is added in reactor, 0.12mol tri- is then added
It is fluorinated borate ether, is warming up to 50 DEG C, is reacted 10 hours, after reaction, the sodium hydroxide solution that 0.1mol/L is added neutralizes, so
Liquid separation obtains organic phase and water phase afterwards, and water phase is extracted with ethyl acetate, and merges organic phase and acetic acid ethyl acetate extract, saturated common salt
Water washing, solvent evaporated, it is 99.4% to be evaporated under reduced pressure and analyze product assay up to 2,3- difluorophenols 12.8g, GC, two-step reaction
Total recovery be 97.9%.
【Embodiment 5】
1) it is added in the reactor prepared by 0.1mol1,2,3- trifluoro-benzenes, 0.2mol ethyl alcohol and 0.02mol embodiments 2
20% potassium doped zirconia solid super basic catalyst is warming up to 50 DEG C, reacts 10 hours, and gas-chromatography tracks reaction process,
It waits for after reaction, 30mL distilled water being added, 20mL ethyl acetate aqueous phase extracteds are used in combination in liquid separation, merge organic phase and acetic acid second
Ester extract liquor distills water washing, anhydrous sodium sulfate drying with 10ML, and solvent evaporated obtains intermediate product.
2) step 1) is obtained into intermediate product and 20mL tetrahydrofurans is added in reactor, 0.12mol tri- is then added
It is fluorinated borate ether, is warming up to 50 DEG C, is reacted 10 hours, after reaction, the sodium hydroxide solution that 0.1mol/L is added neutralizes, so
Liquid separation obtains organic phase and water phase afterwards, and water phase is extracted with ethyl acetate, and merges organic phase and acetic acid ethyl acetate extract, saturation food
Salt water washing, solvent evaporated are evaporated under reduced pressure up to 2,3- difluorophenols 12.5g, and it is 99.8% that GC, which analyzes product assay, and two steps are anti-
The total recovery answered is 96.0%.
【Embodiment 6】
1) 0.1mol1,2,3- trifluoro-benzenes, 3 institute of 0.2mol ethyl alcohol and 0.2mol0.02mol embodiments are added in the reactor
The 10% potassium doped zirconia solid super basic catalyst prepared is warming up to 50 DEG C, reacts 10 hours, gas-chromatography tracking reaction
Process waits for that after reaction 20mL ethyl acetate aqueous phase extracteds are used in combination in addition 30mL distilled water, liquid separation, merge organic phase and second
Acetoacetic ester extract liquor distills water washing, anhydrous sodium sulfate drying with 10ML, and solvent evaporated obtains intermediate product.
2) step 1) is obtained into intermediate product and 20mL tetrahydrofurans is added in reactor, 0.12mol tri- is then added
It is fluorinated borate ether, is warming up to 50 DEG C, is reacted 10 hours, after reaction, the sodium hydroxide solution that 0.1mol/L is added neutralizes, so
Liquid separation obtains organic phase and water phase afterwards, and water phase is extracted with ethyl acetate, and merges organic phase and acetic acid ethyl acetate extract, saturated common salt
Water washing, solvent evaporated, it is 99.4% to be evaporated under reduced pressure and analyze product assay up to 2,3- difluorophenols 12.4g, GC, two-step reaction
Total recovery be 94.8%.
Above description has fully disclosed the specific implementation mode of the present invention.It should be pointed out that being familiar with the field
Technical staff is to any change for being done of specific implementation mode of the present invention all without departing from the range of claims of the present invention.
Correspondingly, the scope of the claims of the invention is also not limited only to previous embodiment.
Claims (10)
1. a kind of method preparing 2,3- difluorophenols, which is characterized in that with 1,2,3- trifluoro-benzene for raw material, including walk as follows
Suddenly：
1) in the presence of solid super base, 3,4,5- trifluorobromobenzenes and alkylol is made to carry out alkoxy substitution reaction, reaction knot
Shu Hou, post-treated be directly entered of reaction mixture are reacted in next step：
2) in the presence of a lewis acid, 2,3-, bis- fluoro- 1- alkoxy benzenes carry out dealkylation, and after reaction, reaction is mixed
Object is closed to handle to obtain 2,3- difluorophenols.
2. the method according to claim 1 for preparing 2,3- difluorophenols, it is characterised in that：In step 1), described consolidates
Body super base is titanium dioxide zirconium base solid super base.
3. the method according to claim 2 for preparing 2,3- difluorophenols, which is characterized in that the titanium dioxide Zirconium-base solid
The preparation method of super base includes the following steps：
Crystallization zirconium chloride wiring solution-forming is taken, pH value of solution=6-8 is adjusted with the KOH of 1mol/L or NH3H2O, is centrifuged,
It washes 4-5 times, then the sediment wiring solution-forming that will be obtained, graphene oxide solution, reflux digestion 12-72h, centrifugation point is added
From, it is dried overnight, then puts the precipitate in and be gradually warming up to 400-700 DEG C, roasting 1-5h in Muffle furnace, obtained titanium dioxide
Zirconium；The zirconium dioxide of the above-mentioned preparations of 70wt%-90wt% and the modification component of 10wt%-30wt%, grinding is taken to be placed on respectively
400-700 DEG C is warming up in tube furnace under N2 or atmosphere of inert gases, 1-5h is heat-treated, obtains solid super strong base catalysis
Agent.
4. the method according to claim 3 for preparing 2,3- difluorophenols, which is characterized in that the heat treatment condition is N2
Or atmosphere of inert gases, heat treatment temperature are 400-700 DEG C, heating rate is 1-10 DEG C/min, heat treatment time 1-5h.
5. the method according to claim 2 for preparing 2,3- difluorophenols, which is characterized in that the alkyl described in step 1)
Alcohol is the alkylol of C1-C8, preferably methanol and ethyl alcohol；The molar ratio of alkylol and 1,2,3- trifluoro-benzenes is 1-10:1；Institute
The alkali stated is alkali metal hydroxide or alkaline earth metal hydroxide, preferably sodium hydroxide and potassium hydroxide；Institute's possession volume alkali
Molar ratio with 1,2,3- trifluoro-benzenes is 1-10:1, preferably 1-5:1..
6. the method according to claim 2 for preparing 2,3- difluorophenols, it is characterised in that：The reaction of step 1) is in nitrogen
It is carried out under atmosphere, reaction temperature is 50-100 DEG C, and the reaction time is 10-20 hours, substantially without polyalkoxylated in reaction process
Product.
7. the method according to claim 2 for preparing 2,3- difluorophenols, it is characterised in that：The post processing mode of step 1)
After reaction, a certain amount of moisture liquid to be added, and water phase is extracted with ethyl acetate, merging organic phase and ethyl acetate extraction
Liquid is taken, water washing, anhydrous sodium sulfate drying, solvent evaporated are distilled.
8. the method according to claim 2 for preparing 2,3- difluorophenols, it is characterised in that：Louis described in step 2)
This acid is alchlor, boron trifluoride ether or iron chloride, preferably, the lewis acid is iron chloride；Lewis acid
Molar ratio with 1,2,3- trifluoro-benzenes is 1:0.8-1.2.
9. the method according to claim 2 for preparing 2,3- difluorophenols, which is characterized in that in step 2), described is anti-
It should be carried out preferably in reaction dissolvent, the organic solvent of selection is ether solvent or alcohols solvent, preferably methanol, ethyl alcohol, second
Ether and tetrahydrofuran；Reaction temperature is 30-50 DEG C, and the reaction time is 2-10 hours.
10. the method according to claim 2 for preparing 2,3- difluorophenols, which is characterized in that the post-processing side of step 2)
Method is after reaction, dilute alkaline soln to be added, and liquid separation obtains organic phase and water phase, and water phase is extracted with ethyl acetate, and merges organic
Phase and acetic acid ethyl acetate extract, saturated common salt water washing, solvent evaporated are evaporated under reduced pressure up to 2,3- difluorophenols.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115108891A (en) * | 2022-07-18 | 2022-09-27 | 烟台盛华液晶材料有限公司 | Preparation method of 3, 5-difluorophenol |
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| US20090215905A1 (en) * | 2004-08-26 | 2009-08-27 | Eriksen Birgitte L | Novel substituted aryloxy alkylamines and their use as monoamine neurotransmitter re-uptake inhibitors |
| CN103877965A (en) * | 2014-04-04 | 2014-06-25 | 湖南大学 | Preparation method and application of tin dioxide-based solid super basic catalyst |
| CN106478377A (en) * | 2016-08-28 | 2017-03-08 | 浙江林江化工股份有限公司 | A kind of synthetic method of 2,3 difluoro 5 bromophenol |
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2018
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| JPH05286882A (en) * | 1992-04-03 | 1993-11-02 | Seimi Chem Co Ltd | Production of 2,3-difluorophenols |
| US20090215905A1 (en) * | 2004-08-26 | 2009-08-27 | Eriksen Birgitte L | Novel substituted aryloxy alkylamines and their use as monoamine neurotransmitter re-uptake inhibitors |
| CN101003468A (en) * | 2007-01-04 | 2007-07-25 | 上海康鹏化学有限公司 | Method for preparing difluoro alkyl ether benzene |
| CN103877965A (en) * | 2014-04-04 | 2014-06-25 | 湖南大学 | Preparation method and application of tin dioxide-based solid super basic catalyst |
| CN106478377A (en) * | 2016-08-28 | 2017-03-08 | 浙江林江化工股份有限公司 | A kind of synthetic method of 2,3 difluoro 5 bromophenol |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115108891A (en) * | 2022-07-18 | 2022-09-27 | 烟台盛华液晶材料有限公司 | Preparation method of 3, 5-difluorophenol |
| CN115108891B (en) * | 2022-07-18 | 2024-04-23 | 烟台盛华液晶材料有限公司 | Preparation method of 3, 5-difluorophenol |
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