CN104649869B - A kind of method that the 2,5-of utilization dichloro 2, 2-Oxydiphenol prepares 2,5-chlorophenesic acid - Google Patents
A kind of method that the 2,5-of utilization dichloro 2, 2-Oxydiphenol prepares 2,5-chlorophenesic acid Download PDFInfo
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- CN104649869B CN104649869B CN201310578781.8A CN201310578781A CN104649869B CN 104649869 B CN104649869 B CN 104649869B CN 201310578781 A CN201310578781 A CN 201310578781A CN 104649869 B CN104649869 B CN 104649869B
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- oxydiphenol
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- 0 *c(cc(cc1)Cl)c1Cl Chemical compound *c(cc(cc1)Cl)c1Cl 0.000 description 1
- RANCECPPZPIPNO-UHFFFAOYSA-N Oc(cc(cc1)Cl)c1Cl Chemical compound Oc(cc(cc1)Cl)c1Cl RANCECPPZPIPNO-UHFFFAOYSA-N 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- 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
- C07C37/055—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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- C—CHEMISTRY; METALLURGY
- 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
- C07C37/64—Preparation of O-metal compounds with O-metal group bound to a carbon atom belonging to a six-membered aromatic ring
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Abstract
The present invention provides one to utilize 2,5 dichloro 2, 2-Oxydiphenol prepare 2, the method of 5 chlorophenesic acids, is under phase transfer catalyst effect, 2,5 dichloro 2, 2-Oxydiphenol are in the presence of a basic, basic hydrolysis occurs in a solvent, and reaction temperature is 120 210 DEG C, and reaction pressure is 0.3～3.0MPa, product postprocessing acidifying obtains 2,5 chlorophenesic acids.Method of the present invention is with 2, and 5 dichloro 2, 2-Oxydiphenol have prepared 2,5 chlorophenesic acids effectively, and in product, 2,5 chlorophenesic acid content are more than 97%, and 2,5 chlorophenesic acids are for 2, and the yield of 5 dichloro 2, 2-Oxydiphenol is more than 95%.2 obtained, 5 chlorophenesic acids it is achieved thereby that the resource recycling of garbage utilizes, can reach the purpose that cleaning produces as the synthesis of raw material direct reuse to Mediben intermediate 3,6 dichlorosalicylic acid again.
Description
Technical field
The present invention relates to the preparation method of a kind of compound, be specifically related to 2, the preparation method of 5-chlorophenesic acid, particularly relate to one
Plant the method utilizing 2,5-dichloro 2, 2-Oxydiphenol to prepare 2,5-chlorophenesic acid.
Background technology
Mediben (dicamba), trade name Dicamba, BAICAO prestige, chemical name 3, the chloro-2-methoxybenzoic acid of 6-bis-, belong to the lowest
Poison, there is the benzoic acid system herbicide of Uptake and translocation effect, by Wei Ersi Cole chemical company of the U.S. (Velsicol Chemical
Corporation) in initiative in 1961, it was developed by Novartis Co., Ltd of Switzerland (Novartis is now incorporated to Syngenta company) later
Preparation.This herbicide is safer to gramineous crop, has notable preventive effect to annual and perennial broadleaf weed, extensively
General for postemergence weed controls such as corn, Semen Maydis, Sorghum vulgare Pers., Caulis Sacchari sinensis, orchard and lawns.Along with external anti-Mediben biotechnology and
Deepening continuously of Mediben mixed herbicide research, market prospect is constantly had an optimistic view of.
Current domestic synthesis Mediben mainly uses 2,5-chlorophenesic acid route to obtain 2-hydroxyl-3,6-dichloro-benzenes through carboxylic acid reaction
Formic acid (3,6-dichlorosalicylic acid), then obtain Mediben through etherificate (O-alkylation) reaction, reaction equation is as follows:
The most Carboxylation process is relatively low due to Synthesis conversion, after solid-liquid separation, remains in 3, residual in 6-dichlorosalicylic acid
2 stayed, 5-chlorophenesic acid enters etherification system in the lump, and with 3,6-dichlorosalicylic acid is etherified in the lump, eventually becomes 2,5-dichloro 2, 2-Oxydiphenol,
Steam in the lump with methanol-water in separating methanol process, be enriched in methanol-water lower floor, as Solid state fermentation.The most uneconomical the most not
Environmental protection, needs a kind of method to be recycled.
The present inventor consults relevant 2, and 5-dichloro 2, 2-Oxydiphenol prepares 2, and the prior art of 5-chlorophenesic acid, discovery document is about this aspect
Report is little, wherein Testaferri, L.;Tiecco,M.;Tingoli,M.;Chianelli,D.;Montanucci,M.213182488;
Tetrahedron;vol.39;nb.1;(1983);P.193-198 2,5-dichloro 2, 2-Oxydiphenol is reported at N, N, N ', N ', N ", N "-hempa
Reacting at 120 DEG C with alkali in amide, the product mainly obtained is 2,5-chlorophenesic acid, and yield only has 8%, wherein 83% turn
Turn to 2,4-dimethoxy chlorobenzene.Through the substantial amounts of experimentation of the present inventor, find Basic fluxing raction system uses a class phase
Transfer catalyst can be greatly improved 2, the yield of 5-chlorophenesic acid, possesses the value of actual industrialization application.
Based on such technical background, the present invention proposes one and utilizes 2, and 5-dichloro 2, 2-Oxydiphenol prepares 2, the method for 5-chlorophenesic acid.
Summary of the invention
It is an object of the invention to: providing one to utilize 2,5-dichloro 2, 2-Oxydiphenol prepares 2, the method for 5-chlorophenesic acid, the method energy
Enough realizing higher 2,5-chlorophenesic acid yield, thus solve industry byproduct 2, the recycling of 5-dichloro 2, 2-Oxydiphenol is asked
Topic.
It is an object of the invention to be achieved through the following technical solutions:
Thering is provided one to utilize 2,5-dichloro 2, 2-Oxydiphenol prepares 2, and the method for 5-chlorophenesic acid, is under phase transfer catalyst effect, and 2,5-
There is basic hydrolysis in dichloro 2, 2-Oxydiphenol, reaction temperature is 120-210 DEG C, reaction pressure the most in a solvent
Power is 0.3～3.0MPa, and product postprocessing acidifying obtains 2,5-chlorophenesic acid.This process reaction equation is as follows:
The inventive method use phase transfer catalyst be preferably in polyethylene glycols, quaternary amine or crown ether-like one or both
Above mixture；More preferably PEG-400, PEG-600, PEG-800 of polyethylene glycols；Or the benzyl of quaternary ammonium salts
Triethyl ammonium chloride, tetrabutyl ammonium bromide, tetrabutylammonium chloride；Or crown ether 18-crown-6.
The alkaline matter preferred as alkali of the inventive method employing or the hydroxide of alkaline-earth metal, more preferably sodium hydroxide or hydrogen
Potassium oxide.
Basic hydrolysis temperature described in the inventive method is preferably 140～190 DEG C.
Basic hydrolysis counter-pressure described in the inventive method is preferably 1.3～2.5MPa.
The percentage ratio of the weight that the phase transfer catalyst consumption described in the inventive method preferably comprises 2,5-dichloro 2, 2-Oxydiphenol is
0.01～2%.
Alkali described in the inventive method and 2, the mol ratio of 5-dichloro 2, 2-Oxydiphenol is preferably 2～10:1, more preferably 2.5～4:1.
Response time preferred more than 3hr, further preferred 6-18hr described in the inventive method.
Solvent described in the inventive method can be water, the little molecule ketone of C3～C6 or alcohols or their mixture, solvent
With 2, the weight ratio of 5-dichloro 2, 2-Oxydiphenol is preferably 1～10:1, more preferably 2～3.5:1.
Acidifying described in the inventive method is preferably used hydrochloric acid acidifying.
2,5-dichloro 2, 2-Oxydiphenol, as a kind of industry byproduct, result from Mediben building-up process in a large number.Prior art is made
For garbage, the most effectively utilize.The method of the present invention is to prepare 2,5-chlorophenesic acid with 2,5-dichloro 2, 2-Oxydiphenol for raw material
Method.After the inventive method processes, 2,5-dichloro 2, 2-Oxydiphenol can prepare 2 with high yield, 5-chlorophenesic acid, Hou Zheyou
Can be as raw material direct reuse to Mediben intermediate 3, the synthesis of 6-dichlorosalicylic acid, it is achieved thereby that the resource of garbage
Recycle, reach the purpose that cleaning produces.
In the product that the inventive method obtains 2,5-chlorophenesic acid content is more than 97%, 2,5-chlorophenesic acids for 2,5-dichloro 2, 2-Oxydiphenol
Yield more than 95%.
Detailed description of the invention
Embodiment 1:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 480Kg, 50% potassium hydroxide aqueous solution
280Kg, PEG-8003.5kg, stirring heats up, and controls temperature 140 DEG C, pressure 0.35MPa, is incubated hydrolysis 18hr,
After cooling release, putting in post processing still, hydrochloric acid is acidified, and is layered in temperature 60-70 DEG C, receives 2,5-chlorophenesic acid 162.0Kg,
Content 97.1%, yield 96.5%.
Embodiment 2:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 380Kg, 30% sodium hydrate aqueous solution
333Kg, PEG-4003.5kg, stirring heats up, and controls temperature 140 DEG C, pressure 0.35MPa, is incubated hydrolysis 18hr.
After cooling release, feed liquid adds water-soluble salt, puts in post processing still, after hydrochloric acid acidifying, is layered in temperature 60-70 DEG C, receives 2,5-
Chlorophenesic acid 161.3Kg, content 97.4%, yield 96.4%.
Embodiment 3:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 380Kg, 30% sodium hydrate aqueous solution
333Kg, tetrabutyl ammonium bromide 0.35Kg, stirring heats up, and controls temperature 160 DEG C, pressure 0.60MPa, and insulation hydrolysis is anti-
Answer 20hr.After cooling release, put in post processing still, after hydrochloric acid acidifying, be layered in temperature 60-70 DEG C, receive 2,5-dichloro
Phenol 163.5Kg, content 97.5%, yield 97.8%.
Embodiment 4:
In 1000L autoclave, the 2 of input 177KG, 5-dichloro 2, 2-Oxydiphenol, water 380KG, 30% sodium hydrate aqueous solution
333Kg, benzyltriethylammoinium chloride 0.35Kg, stirring heats up, and controls temperature 160 DEG C, pressure 0.60MPa, is incubated water
Solve reaction 12hr, after cooling release, put in post processing still, after hydrochloric acid acidifying, be layered in temperature 60-70 DEG C, receive 2,5-
Chlorophenesic acid 162.5Kg, content 97.3%, yield 97.0%.
Embodiment 5:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 380KG, 30% sodium hydrate aqueous solution
333Kg, tetrabutylammonium chloride 0.35Kg, stirring heats up, and controls temperature 160 DEG C, pressure 0.60MPa, and insulation hydrolysis is anti-
Answer 12hr, after cooling release, put in post processing still, after hydrochloric acid acidifying, be layered in temperature 60-70 DEG C, receive 2,5-dichloro
Phenol 161.7Kg, content 97.2%, yield 96.4%.
Embodiment 6:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 380Kg, 30% sodium hydrate aqueous solution
The 18-crown-6 of 333Kg, 0.020Kg, stirring heats up, and controls temperature 160 DEG C, pressure 0.6MPa, is incubated hydrolysis 8hr,
After cooling release, put in post processing still, after hydrochloric acid acidifying, be layered in temperature 60-70 DEG C, receive 2,5-chlorophenesic acid 161.7Kg,
Content 97.2%, yield 96.4%.
Embodiment 7:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 400Kg, 50% potassium hydroxide aqueous solution
448Kg, tetrabutyl ammonium bromide 0.35Kg, stirring heats up, and controls temperature 190 DEG C, pressure 1.25MPa, and insulation hydrolysis is anti-
After answering 6hr. cooling release, put in post processing still, after hydrochloric acid acidifying, be layered in temperature 60-70 DEG C, receive 2,5-dichloro-benzenes
Phenol 163.2Kg, content 97.3%, yield 97.4%.
Embodiment 8:
In 1000L autoclave, the 2 of input 177KG, 5-dichloro 2, 2-Oxydiphenol, water 200Kg, 30% sodium hydrate aqueous solution
533Kg, benzyltriethylammoinium chloride 0.35Kg, stirring heats up, and controls reaction temperature 190 DEG C, pressure 1.25MPa, protects
Temperature hydrolysis 6hr, after cooling release, puts in post processing still, after hydrochloric acid acidifying, is layered in temperature 60-70 DEG C, receives 2,5-
Chlorophenesic acid 161.4Kg, content 97.1%, yield 96.14%.
Embodiment 9:
In 2000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, acetone 350Kg, solid potassium hydroxide 168Kg,
Tetrabutylammonium chloride 0.35Kg, stirring is warmed up to 160 DEG C, and pressure 1.7MPa is incubated hydrolysis 10hr, release of lowering the temperature
After, adding 800L water-soluble salt, put in precipitation still, on normal pressure, tower precipitation reclaims acetone to 95 DEG C.After the acidifying of clout hydrochloric acid,
It is layered in temperature 60-70 DEG C, receipts 2,5-chlorophenesic acid 161.8Kg, content 97.3%, yield 96.58%.
Embodiment 10:
In 2000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, methanol 350Kg, solid potassium hydroxide 168Kg,
Tetrabutyl ammonium bromide 0.35Kg, stirring is warmed up to 160 DEG C, and pressure 1.7MPa is incubated hydrolysis 3hr, release of lowering the temperature
After, adding 800L water-soluble salt, put in precipitation still, on normal pressure, tower precipitation reclaims methanol to 95 DEG C.After the acidifying of clout hydrochloric acid,
It is layered in temperature 60-70 DEG C, receipts 2,5-chlorophenesic acid 150.4Kg, content 97.0%, yield 94.35%.
Embodiment 11:
In 2000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, ethanol 350Kg, solid sodium hydroxide 160Kg,
Benzyltriethylammoinium chloride 0.35Kg, stirring is warmed up to 160 DEG C, pressure 1.25MPa, is incubated hydrolysis 10hr, cooling
After release, adding 800L water-soluble salt, put in precipitation still, on normal pressure, tower precipitation reclaims ethanol to 100 DEG C.The acid of clout hydrochloric acid
After change, it is layered in temperature 60-70 DEG C, receipts 2,5-chlorophenesic acid 160.8Kg, content 97.2%, yield 95.88%.
When following comparative example shows to be added without in reaction system phase transfer catalyst, Dichlorophenol ether is originally not converted into dichloro
Phenol.
Comparative example 1:
In 1000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, water 380Kg, 30% sodium hydrate aqueous solution
333Kg, stirring heats up, and controls temperature 140 DEG C, pressure 0.35MPa, is incubated hydrolysis 18hr, after cooling release,
Feed liquid adds water-soluble salt, puts in post processing still, after hydrochloric acid acidifying, is layered in temperature 60-70 DEG C, rewinding 175.7Kg, 2,5-
Dichlorophenol content 5.29%.
Comparative example 2:
In 2000L autoclave, the 2 of input 177Kg, 5-dichloro 2, 2-Oxydiphenol, acetone 350Kg, solid potassium hydroxide 168Kg,
Stirring is warmed up to 160 DEG C, pressure 1.7MPa, is incubated hydrolysis 10hr, after cooling release, adds 800L water-soluble salt,
Putting in precipitation still, on normal pressure, tower precipitation reclaims acetone to 95 DEG C.After the acidifying of clout hydrochloric acid, it is layered in temperature 60-70 DEG C,
Rewinding 173.1Kg, 2,5-Dichlorophenol content 16.98%.
Claims (10)
1. one kind utilizes 2, and 5-Banair prepares 2, and the method for 5-chlorophenesic acid, is under phase transfer catalyst effect, and 2,5-
In the presence of a basic, there is basic hydrolysis in Banair, reaction temperature is 120-210 DEG C, reaction pressure in a solvent
Power is 0.3～3.0MPa, and product postprocessing acidifying obtains 2,5-chlorophenesic acid, and this process reaction equation is as follows:
2. the method described in claim 1, it is characterised in that: described phase transfer catalyst be polyethylene glycols, quaternary ammonium salt or
One or more mixture in crown ether-like.
3. the method described in claim 2, it is characterised in that: described polyethylene glycols selected from PEG-400, PEG-600,
Or PEG-800.
4. the method described in claim 2, it is characterised in that: described quaternary ammonium salt is selected from benzyltriethylammoinium chloride, four fourths
Base ammonium bromide or tetrabutylammonium chloride.
5. the method described in claim 2, it is characterised in that: described crown ether-like is 18-crown-6.
6. the method described in claim 1, it is characterised in that: described phase transfer catalyst weight is 2,5-Banair weight
The 0.01～2% of amount.
7. the method described in claim 1, it is characterised in that: described alkaline matter is selected from alkali metal or the hydrogen-oxygen of alkaline-earth metal
Compound.
8. the method described in claim 1, it is characterised in that: described alkaline matter and 2, the mol ratio of 5-Banair is
2～10:1.
9. the method described in claim 1, it is characterised in that: described reaction temperature is 140～190 DEG C；Described reaction pressure
Power is 1.3～2.5MPa；The described response time is 6-18hr.
10. the method described in claim 1, it is characterised in that: described solvent is water, the little molecule ketone of C3～C6, C3～C6
Small molecule alcohol or their mixture, solvent and 2, the weight ratio of 5-Banair is 1～10:1.
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| CN201310578781.8A CN104649869B (en) | 2013-11-18 | 2013-11-18 | A kind of method that the 2,5-of utilization dichloro 2, 2-Oxydiphenol prepares 2,5-chlorophenesic acid |
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| CN201310578781.8A CN104649869B (en) | 2013-11-18 | 2013-11-18 | A kind of method that the 2,5-of utilization dichloro 2, 2-Oxydiphenol prepares 2,5-chlorophenesic acid |
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| CN105906482B (en) * | 2016-05-19 | 2019-02-12 | 江苏优嘉植物保护有限公司 | A method of 2,5- chlorophenesic acid is prepared using 2,5- dichloro phenolic ether |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| PL78745B1 (en) * | 1972-11-28 | 1975-06-30 | ||
| CN101037380A (en) * | 2007-04-29 | 2007-09-19 | 上海康鹏化学有限公司 | Preparation method of 2,3-Difluoro-5-Bromophenol |
| CN101062887A (en) * | 2006-04-30 | 2007-10-31 | 中国科学院成都有机化学有限公司 | Method for synthesizing o-phenylphenol |
| CN102557910A (en) * | 2011-12-27 | 2012-07-11 | 上海立科药物化学有限公司 | Deprotection method for phenolic hydroxyl group |
-
2013
- 2013-11-18 CN CN201310578781.8A patent/CN104649869B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| PL78745B1 (en) * | 1972-11-28 | 1975-06-30 | ||
| CN101062887A (en) * | 2006-04-30 | 2007-10-31 | 中国科学院成都有机化学有限公司 | Method for synthesizing o-phenylphenol |
| CN101037380A (en) * | 2007-04-29 | 2007-09-19 | 上海康鹏化学有限公司 | Preparation method of 2,3-Difluoro-5-Bromophenol |
| CN102557910A (en) * | 2011-12-27 | 2012-07-11 | 上海立科药物化学有限公司 | Deprotection method for phenolic hydroxyl group |
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