CN104961629A - Synthetic method of pentafluorophenol - Google Patents

Synthetic method of pentafluorophenol Download PDF

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Publication number
CN104961629A
CN104961629A CN201510255681.0A CN201510255681A CN104961629A CN 104961629 A CN104961629 A CN 104961629A CN 201510255681 A CN201510255681 A CN 201510255681A CN 104961629 A CN104961629 A CN 104961629A
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synthetic method
ethyl ketone
pentafluorophenol
fluoro benzene
penta fluoro
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CN201510255681.0A
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Inventor
许凤军
刘剑
王谦
王艳伟
谭新
迟朝辉
王玉华
丁永静
曲海波
邵林
官贵文
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Yantai Biofengs Pharm-Tech Co Ltd
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Yantai Biofengs Pharm-Tech Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C37/00Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
    • C07C37/50Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by reactions decreasing the number of carbon atoms
    • C07C37/56Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by reactions decreasing the number of carbon atoms by replacing a carboxyl or aldehyde group by a hydroxy group

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The invention relates to a synthetic method of pentafluorophenol. According to the synthetic method, Pentafluoroacetophenone is taken as a raw material, a persulfate is taken as an oxidizing agent, a sulfuric acid solution is taken as a catalyst, glacial acetic acid is taken as a solvent, and pentafluorophenol products are obtained via reaction at normal temperature under normal pressure. According to the synthetic method, normal temperature, normal pressure, and acidic reaction conditions are adopted; high temperature, high pressure, or alkaline reaction conditions in the prior art are avoided; it is beneficial for increasing of product quality, and is beneficial for industrialized production; and at the same time, raw materials of the synthetic method are cheap and easily available, synthetic reaction yield is high, product cost is reduced greatly, and economic benefit is high.

Description

A kind of synthetic method of Pentafluorophenol
Technical field
The present invention relates to a kind of synthetic method of Pentafluorophenol, belong to field of medicine and chemical technology.
Background technology
Pentafluorophenol is a kind of important fluorine-containing phenols intermediate, is widely used in the synthesis field of the compounds such as medicine, agricultural chemicals, liquid crystal, polymer.Its molecular formula is C 6hF 5o, be a kind of white crystals body, easily absorb water, fusing point is 34 ~ 36 DEG C, boiling point is 143 DEG C.
In existing bibliographical information, Pentafluorophenol synthesizes mainly through following several route:
Route [1]: substituting group is halogen atom, as fluorine atom, chlorine atom, bromine atoms etc., at patent CN102887817, FR1408501, GB887691, NL6505906, US3429935 and document J.Org.Chem.Vol.56 (26), 1991, there is relevant discussion in 7350-7354, normally directly use alkali (or in tube sealing) hydrolysis in high temperature (>=175 DEG C) and autoclave to obtain product.The raw material that this route uses is except phenyl-hexafluoride is not easy to obtain, and all the other can more conveniently obtain, simple to operate.But this route has following deficiency: High Temperature High Pressure is higher to equipment requirements on the one hand, on aromatic ring, the activity of other fluorine atom itself is also very high on the other hand, under so violent condition, very easily there is polysubstituted and defluorination reaction, the impurity that reaction produces is more, for subsequent purification adds difficulty, be unfavorable for suitability for industrialized production.
Route [2]: produce Grignard reagent with five bromofluorobenzenes, then instill superoxide (as tertbutyl peroxide) and carry out oxidizing reaction, yield is 67.5% ~ 77.1%, has a detailed description in patent CN1847210.Grignard method is employed in this route, the cost of grignard reaction is higher on the one hand, the activity of five bromofluorobenzene Grignard reagents is very high on the other hand, highly active compound like this is added in a kind of superoxide, the reaction almost reaction in explosion type, the difficulty of reaction controlling is very large, very easily causes the generation of a large amount of by product.In patent CN1847210, crude product purity is 87.1% ~ 89.4%, is unfavorable for suitability for industrialized production.
Route [3]: with pentafluorophenyl boric acid or penta phenyl fluoride boron acid esters for raw material, be oxidized by hydrogen peroxide, at patent CN102718635, CN103420801 and document TetrahedronLett., Vol.34, have specific descriptions in 1964,2991-2993.Such reaction has the high feature of reaction purity, but also there is the problem that expensive starting materials is not easy to obtain (pentafluorophenyl boric acid or penta phenyl fluoride boron acid esters all need just can produce through grignard or Lithiation with halo penta fluoro benzene) simultaneously, is difficult to industrialization.
Route [4]: with pentafluorophenyl group ether for raw material, be hydrolyzed by Lewis acid (as aluminum chloride, boron trifluoride etc.) or the catalysis of palladium carbon and obtain Pentafluorophenol, at patent CN103787839 and document J.Chem.Soc., 1959,2019-2021, Science, Vol127, has discussion in 1958,643-644 etc.This method Problems existing mainly ethers synthesis need condition too harsh; usually be all react with highly basic under high temperature; similar to route [1]; this can cause other fluorine atom on aromatic ring to carry out etherificate and defluorinate phenomenon usually; therefore the purity of product and yield not high; also need special equipment to carry out purification process simultaneously, be unfavorable for producing.
In addition, penta fluoro benzene amine also can prepare Pentafluorophenol through diazotization reaction in theory, as shown in route [5], does not find relevant record temporarily in existing periodical.To generate p-fluorophenol through diazotization reaction similar with para-fluoroaniline, this reaction scheme all also exists: diazotization can produce a large amount of containing acid, nitrogenous effluent, be unfavorable for sewage disposal, the shortcoming of route [5] is also similar, is therefore also unfavorable for suitability for industrialized production.
In a word, all there are starting material and be not easy to obtain or severe reaction conditions or the problem such as by product is many in existing several Pentafluorophenol synthetic method, needs the method for the industrialization synthesis Pentafluorophenol that a kind of starting material are inexpensive, reaction conditions is gentle badly.
Summary of the invention
The present invention is directed to the deficiency that above-mentioned prior art exists, a kind of synthetic method of Pentafluorophenol is provided.
The technical scheme that the present invention solves the problems of the technologies described above is as follows: a kind of synthetic method of Pentafluorophenol, with penta fluoro benzene ethyl ketone for raw material, makes oxygenant with persulphate, sulphuric acid soln makes catalyzer, Glacial acetic acid, as solvent, is obtained by reacting product under normal temperature, normal pressure, and its reaction equation is:
The concrete steps of above-mentioned synthetic method are as follows:
(1) with penta fluoro benzene ethyl ketone for raw material, add solvent Glacial acetic acid and oxygenant persulphate, stir, be cooled to 10 ~ 15 DEG C, in 1 ~ 2h, drip catalyst sulfuric acid solution, during dropping be incubated 10 ~ 40 DEG C;
(2) mixing solutions step (1) obtained is at 10 ~ 60 DEG C of insulation reaction 3 ~ 8h, and tracing detection, to penta fluoro benzene ethyl ketone reacts completely;
(3) in the resultant in step (2), add 250 ~ 350g water, stir 15 ~ 30min, extract at twice with 500g methyl tertiary butyl ether, combining extraction liquid is 5 ~ 7 with water or saturated brine drip washing to middle pH, dry, normal pressure desolvation, obtains Pentafluorophenol product.
Reaction principle of the present invention is: with penta fluoro benzene ethyl ketone for raw material production Pentafluorophenol, its reaction mechanism is that penta fluoro benzene ethyl ketone and persulfuric acid react, reset through Bayer-Villiger and form over cure acid esters, then be hydrolyzed after the effect of acid and obtain Pentafluorophenol, course is as follows:
The invention has the beneficial effects as follows: the present invention uses normal temperature, normal pressure, acid-reaction condition, avoids high temperature of the prior art, high pressure or basic reaction conditions, be conducive to the quality improving product, be conducive to suitability for industrialized production; Meanwhile, low in raw material price of the present invention is easy to get, and building-up reactions yield is high, and the cost of product is reduced greatly, creates larger economic benefit.
On the basis of technique scheme, the present invention can also do following improvement.
Further, described oxygenant persulphate is one or more in Potassium Persulphate, Sodium Persulfate or ammonium persulphate, is preferably Sodium Persulfate or ammonium persulphate.
Further, described penta fluoro benzene ethyl ketone and the consumption mol ratio of oxygenant persulphate are 1:(2 ~ 6), preferable amount mol ratio is 1:(3 ~ 5).
Further, described penta fluoro benzene ethyl ketone and the consumption mol ratio of catalyst sulfuric acid solution are 1:(1 ~ 4), preferable amount mol ratio is 1:(2 ~ 3).
Further, described penta fluoro benzene ethyl ketone and the consumption mol ratio of Glacial acetic acid are 1:(8 ~ 20), preferable amount mol ratio is 1:(10 ~ 15).
Further, the mass concentration of described catalyst sulfuric acid solution is 50 ~ 75%, is preferably 55 ~ 70%.
Further, the holding temperature described in step (2) is preferably 10 ~ 40 DEG C, and the reaction times is preferably 4 ~ 6h.
Accompanying drawing explanation
Fig. 1 is the mass spectrum that the embodiment of the present invention 1 obtains product;
Fig. 2 is the infrared spectrum that the embodiment of the present invention 1 obtains product.
Embodiment
Be described principle of the present invention and feature below in conjunction with example, example, only for explaining the present invention, is not intended to limit scope of the present invention.
Embodiment 1
Penta fluoro benzene ethyl ketone 105 grams (0.5 mole), 360 grams, Glacial acetic acid (6 moles) and ammonium persulphate 342 grams (1.5 moles) is added in 2L there-necked flask, stir, be cooled to 10 DEG C ~ 15 DEG C, drip the sulphuric acid soln 170 grams (1 mole) that mass concentration is 60%, temperature control 10 DEG C ~ 40 DEG C during dropping, drips off for about 1 hour, dropwise, in 20 DEG C ~ 50 DEG C insulation reaction 4 ~ 5 hours, GC tracing detection, to penta fluoro benzene ethyl ketone reacted completely.Insulation is finished, add 250 grams of water, stir 15 minutes, then extract for 2 times with methyl tertiary butyl ether 500 grams points, combining extraction liquid, being washed till pH with saturated brine is 5 ~ 6, with anhydrous sodium sulphate 50 grams of dryings 5 hours, normal pressure desolvation, obtained product 85.7 grams, gas chromatographic purity: 99.0%, yield: 93.1%; Underpressure distillation again, obtains product 82.2 grams, gas chromatographic purity: 99.7%, yield: 89.4%, fusing point 34.5 DEG C ~ 35.2 DEG C.
Fig. 1, Fig. 2 are respectively mass spectrum and the infrared spectrum of the present embodiment the finished product.In figure, data are as follows: GC-MS (EI, 70eV): m/z (%)=184.0,155.0,136.0,117.0,86.0,55.0;
IR(KBr):3512,3057,2461,2615(w),1538,1521,1486,1471,1356,1316,1236,998,982,663,479cm -1
Embodiment 2
Penta fluoro benzene ethyl ketone 105 grams (0.5 mole) is added in 2L there-necked flask, 300 grams, Glacial acetic acid (5.0 moles) and Sodium Persulfate 595 grams (2.5 moles), stir, be cooled to 10 DEG C ~ 15 DEG C, drip the sulphuric acid soln 85 grams (0.5 mole) that mass concentration is 60%, temperature control 10 DEG C ~ 40 DEG C during dropping, within about 2 hours, drip off, dropwise, in 20 DEG C ~ 50 DEG C insulation reaction 6 ~ 7 hours, tracing detection, to penta fluoro benzene ethyl ketone reacts completely.Insulation is finished, add 250 grams of water, stir 30 minutes, then extract for 2 times with methyl tertiary butyl ether 500 grams points, combining extraction liquid, pH to 5 ~ 6 are washed till with saturated brine, with anhydrous sodium sulphate 50 grams of dryings 5 hours, normal pressure desolvation, obtained product 84.1 grams, gas chromatographic purity: 98.6%, yield: 91.4%; Underpressure distillation again, obtains product 79.6 grams, gas chromatographic purity: 99.5%, yield: 86.5%, fusing point 34.1 DEG C ~ 35.2 DEG C.
Embodiment 3
Penta fluoro benzene ethyl ketone 105 grams (0.5 mole) is added in 2L there-necked flask, 450 grams, Glacial acetic acid (7.5 moles) and ammonium persulphate 228 grams (1.0 moles), stir, be cooled to 10 DEG C ~ 15 DEG C, drip the sulphuric acid soln 255 grams (1.5 moles) that mass concentration is 60%, temperature control 10 DEG C ~ 40 DEG C during dropping, within about 2 hours, drip off, dropwise, in 20 DEG C ~ 50 DEG C insulation reaction 3 ~ 4 hours, GC tracing detection, to penta fluoro benzene ethyl ketone reacts completely.Insulation is finished, and adds 350 grams of water, stirs 30 minutes, again with methyl tertiary butyl ether 500 grams of points of 2 extractions, combining extraction liquid, with water wash to neutral, with anhydrous sodium sulphate 50 grams of dryings 5 hours, normal pressure desolvation, obtained product 88.0 grams, gas chromatographic purity: 99.2%, yield: 95.7%, then underpressure distillation, obtain product 84.5 grams, gas chromatographic purity: 99.6%, yield: 91.8%, fusing point 34.6 DEG C ~ 35.3 DEG C.
Embodiment 4
Penta fluoro benzene ethyl ketone 105 grams (0.5 mole) is added in 2L there-necked flask, 600 grams, Glacial acetic acid (10 moles) and ammonium persulphate 684 grams (3.0 moles), stir, be cooled to 10 DEG C ~ 15 DEG C, drip the sulphuric acid soln 340 grams (2.0 moles) that mass concentration is 60%, temperature control 10 DEG C ~ 40 DEG C during dropping, within about 1.5 hours, drip off, dropwise, in 20 DEG C ~ 50 DEG C insulation reaction 3 ~ 4 hours, GC tracing detection, to penta fluoro benzene ethyl ketone reacts completely.Insulation is finished, and adds 250 grams of water, stirs 30 minutes, then use methyl tertiary butyl ether 250 grams × 2 to extract, combining extraction liquid, with water wash to neutral, with anhydrous sodium sulphate 50 grams of dryings 5 hours, normal pressure desolvation, obtain product 88.0 grams, gas chromatographic purity: 99.2%, yield: 95.7%; Underpressure distillation again, obtains product 84.5 grams, gas chromatographic purity: 99.6%, yield: 91.8%, fusing point 33.9 DEG C ~ 34.8 DEG C.
Comparative example
210 grams, water is added successively in 1L beaker, 17 grams, sodium hydroxide (0.43 mole) and 35 grams, sodium carbonate (0.33 mole), be stirred to entirely molten after be transferred to inside autoclave, add five bromofluorobenzene 74.1 grams (0.3 mole) and 3.58 grams, Red copper oxide (0.025 mole) again, enclosed high pressure still, nitrogen replacement 2 times, slowly be warming up to 140 DEG C, and reaction was cooled to room temperature after 3 hours at 140 DEG C ~ 150 DEG C, Pentafluorophenol sodium material is poured out, filter, be hydrochloric acid acidifying at 15 ~ 20 DEG C of 30% by 63 grams of concentration by filtrate, pH is 4 ~ 6, after acidifying, extract at twice with the methyl tertiary butyl ether of 250 grams, merge organic phase, be concentrated into dry, obtain Pentafluorophenol crude product, GC analyzes, the content of Pentafluorophenol accounts for 10%, passed through post to be separated, the yield of Pentafluorophenol is 5.8%.
As can be seen from four embodiments and comparative example analysis, the synthetic method that the present invention uses is temperature required lower, raw materials used cheap and easy to get, and the yield of product Pentafluorophenol and purity are well beyond comparative example.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (7)

1. a synthetic method for Pentafluorophenol, is characterized in that, with penta fluoro benzene ethyl ketone for raw material, make oxygenant with persulphate, sulphuric acid soln makes catalyzer, and Glacial acetic acid, as solvent, is obtained by reacting Pentafluorophenol product under normal temperature, normal pressure.
2. synthetic method according to claim 1, is characterized in that, concrete steps are as follows:
(1) with penta fluoro benzene ethyl ketone for raw material, add solvent Glacial acetic acid and oxygenant persulphate, stir, be cooled to 10 ~ 15 DEG C, in 1 ~ 2h, drip catalyst sulfuric acid solution, during dropping be incubated 10 ~ 40 DEG C;
(2) mixing solutions step (1) obtained is at 10 ~ 60 DEG C of insulation reaction 3 ~ 8h, and tracing detection, to penta fluoro benzene ethyl ketone reacts completely;
(3) in the resultant in step (2), add 250 ~ 350g water, stir 15 ~ 30min, extract at twice with 500g methyl tertiary butyl ether, combining extraction liquid is 5 ~ 7 with water or saturated brine drip washing to pH, dry, normal pressure desolvation, obtains Pentafluorophenol product.
3. synthetic method according to claim 1 and 2, is characterized in that, described oxygenant persulphate is one or more in Potassium Persulphate, Sodium Persulfate or ammonium persulphate.
4. synthetic method according to claim 1 and 2, is characterized in that, described penta fluoro benzene ethyl ketone and the consumption mol ratio of oxygenant persulphate are 1:(2 ~ 6).
5. synthetic method according to claim 1 and 2, is characterized in that, described penta fluoro benzene ethyl ketone and the consumption mol ratio of catalyst sulfuric acid solution are 1:(1 ~ 4).
6. synthetic method according to claim 1 and 2, is characterized in that, described penta fluoro benzene ethyl ketone and the consumption mol ratio of Glacial acetic acid are 1:(8 ~ 20).
7. synthetic method according to claim 1 and 2, is characterized in that, the mass concentration of described catalyst sulfuric acid solution is 50 ~ 75%.
CN201510255681.0A 2015-05-19 2015-05-19 Synthetic method of pentafluorophenol Pending CN104961629A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108047000A (en) * 2017-12-13 2018-05-18 衢州康鹏化学有限公司 A kind of preparation method of Pentafluorophenol

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4950809A (en) * 1987-12-11 1990-08-21 Rhone-Poulenc Chimie Process for preparing hydroxylated aromatic derivatives by the Baeyer-Villiger reaction
CN1463961A (en) * 2002-06-27 2003-12-31 烟台万润精细化工有限责任公司 Process for preparing phenol derivative
CN1874210A (en) * 2005-06-03 2006-12-06 Ut斯达康(中国)有限公司 Method for transmitting and receiving quasi-orthogonal time space group code, transmitter and receiver, and communication system
CN101007752A (en) * 2007-01-19 2007-08-01 烟台九目化学制品有限公司 Phenol analog derivative preparation method
CN102887817A (en) * 2012-09-11 2013-01-23 浙江永太科技股份有限公司 Novel method for synthesizing 2,3,4,5,6-pentafluorophenol

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4950809A (en) * 1987-12-11 1990-08-21 Rhone-Poulenc Chimie Process for preparing hydroxylated aromatic derivatives by the Baeyer-Villiger reaction
CN1463961A (en) * 2002-06-27 2003-12-31 烟台万润精细化工有限责任公司 Process for preparing phenol derivative
CN1874210A (en) * 2005-06-03 2006-12-06 Ut斯达康(中国)有限公司 Method for transmitting and receiving quasi-orthogonal time space group code, transmitter and receiver, and communication system
CN101007752A (en) * 2007-01-19 2007-08-01 烟台九目化学制品有限公司 Phenol analog derivative preparation method
CN102887817A (en) * 2012-09-11 2013-01-23 浙江永太科技股份有限公司 Novel method for synthesizing 2,3,4,5,6-pentafluorophenol

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108047000A (en) * 2017-12-13 2018-05-18 衢州康鹏化学有限公司 A kind of preparation method of Pentafluorophenol

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