CN105348200A - Environment-friendly method for metronidazole synthesis - Google Patents
Environment-friendly method for metronidazole synthesis Download PDFInfo
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- CN105348200A CN105348200A CN201510978971.8A CN201510978971A CN105348200A CN 105348200 A CN105348200 A CN 105348200A CN 201510978971 A CN201510978971 A CN 201510978971A CN 105348200 A CN105348200 A CN 105348200A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D233/00—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings
- C07D233/54—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
- C07D233/66—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D233/91—Nitro radicals
- C07D233/92—Nitro radicals attached in position 4 or 5
- C07D233/94—Nitro radicals attached in position 4 or 5 with hydrocarbon radicals, substituted by oxygen or sulfur atoms, attached to other ring members
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Abstract
The invention discloses an environment-friendly method for metronidazole synthesis. Formic acid is replaced with acetic acid, alcohol is added for esterification, neutralization is performed for three times, sodium sulfate and ethylene glycol are recovered, a nitration product is effectively recovered from a metronidazole mother solution, derivatives such as acetic ester, anhydrous sodium sulfate and the like are obtained, by-products such as ethylene glycol and the like are chemical raw materials with wide applications, resources are recycled, the raw materials are greatly saved, the production cost is reduced, and the whole novel process adopts simple steps and is convenient to operate.
Description
Technical field
The invention belongs to pharmacy field, be specifically related to the environmental protection method of a kind of metronidazole synthesis.
Background technology
Metronidazole chemistry 1-(2-hydroxyethyl)-2-5-nitro imidazole by name, it is a kind of nitroimidazole antibiotics, be used to treatment trichomonal vaginitis or for killing the anerobe causing oral cavity infection at first, within 1978, the World Health Organization is defined as the specific medicament of anti anaerobic bacteria infection, is widely used in prevention and therapy oral cavity anaerobium and infects.Metronidazole is also usually used in the infection of prevention and therapy because of the microbial respiratory tract of anaerobism, digestive tube, abdominal cavity, pelvic cavity etc., skin soft tissue and bone joint infection, the illnesss such as heart film inflammation, septicemia.
In traditional technology, metronidazole API uses the raw material such as formic acid, sulfuric acid large to equipment corrosion in a large number, entered complicated reaction and postprocessing working procedures, containing raw material, reaction product and other organism that multiple unreacted is complete in the waste water produced, the pollutents such as salt (mainly production process becomes the sodium sulfate of generation, sodium formiate).If the organism in waste water directly discharges, easily cause the eutrophication of water body, and decomposite multiple obnoxious flavour, not only cause serious water pollution also can polluted air; Inorganic salts ingredients in waste water is single not, be difficult to be separated, too high salt branch makes water PH value change, destroy water body nature shock absorption, inhibit bacterium and microbial growth, hinder the self-purification of water body, also add water hardness greatly simultaneously, cause the salinization of soil, seriously destroy environment.
On the other hand, these organism contained in waste water and inorganic salt are all important industrial chemicals, if through a series of separation or derivatization treatment, can produce huge economy, environmental benefit.
Summary of the invention
The present invention is directed to traditional metronidazole productive profit little, the sewage produced is reluctant problem due to the gas chromatography, inorganic salt etc. containing not easily separated removing, provides a kind of environmental protection method of synthesizing metronidazole coproduction itrated compound.
For realizing object of the present invention, provide following concrete technical scheme:
A synthetic method for metronidazole, comprises the following steps:
(1) acetic acid and sulfuric acid mixed according to the ratio of weight ratio 1:0.5 ~ 5 and be made into nitration mixture, add 2-5-nitro imidazole, heating for dissolving, the weight ratio of 2-5-nitro imidazole and described nitration mixture is 1:0.5 ~ 4.
(2) in 90 ~ 100 DEG C of systems obtained to step (1), pass into oxyethane and the vitriol oil, react 10 ~ 60 minutes;
(3) step (2) reacted reaction solution is cooled to 10 ~ 40 DEG C, adds liquid caustic soda and regulate pH to 2 ~ 4, filter, reclaim the itrated compound crystallization of separating out;
(4) by the filtrate of step (3) at 20 ~ 60 DEG C, regulate pH to 10 ~ 12 with liquid caustic soda, separate out metronidazole crude product, filter, drying obtains metronidazole crude product.
Preferably, wherein the weight ratio of step (2) ethylene oxide and 2-5-nitro imidazole is 1:0.8 ~ 3.
Preferably, wherein the weight ratio of step (2) ethylene oxide and the vitriol oil is 1:0.1 ~ 1.
Preferably, the reaction times of described step (2) is 20 ~ 40 minutes.
Preferably, wherein step (2) is for alternately passing into oxyethane at 90 ~ 100 DEG C and drip 98% vitriol oil, logical complete, insulation reaction 10 ~ 60 minutes, and the total amount of its ethylene oxide and the weight ratio of 2-5-nitro imidazole are 1:0.8 ~ 3; The weight ratio of 98% vitriol oil of oxyethane and dropping is 1:0.1 ~ 1.
The technical scheme of the application, except coproduction itrated compound, can also coproduction acetic ester.Preferably, wherein step (3) is, cooling reaction solution, to 20 ~ 50 DEG C, adds lower alcohol, 60 ~ 80 DEG C of backflows 0.5 ~ 2 hour, and Distillation recovery acetic ester; Be cooled to 20 ~ 40 DEG C again, add liquid caustic soda and regulate pH to 2 ~ 3, filter, reclaim the itrated compound crystallization of separating out.
Further preferably, the weight ratio of the acetic acid of described lower alcohol and step (1) is 1:0.5 ~ 1.
Further preferably, described lower alcohol is selected from the one in methyl alcohol, ethanol or Virahol.
The technical scheme of the application, can also further secondary recovery itrated compound.Preferably, described method also comprises step:
(5) filtrate step (4) obtained regulates pH to 4 ~ 7 at 30 ~ 50 DEG C, filters, and reclaims the secondary recovery itrated compound of separating out.
The technical scheme of the application, can also coproduction anhydrous sodium sulphate.Preferably, described method also comprises step:
(6) filtrate the carrying out that step (5) obtains is evaporated to about 1/4 of original volume, at 35 ~ 100 DEG C of crystallizatioies, filters, dry anhydrous sodium sulphate.
The technical scheme of the application, can also coproduction ethylene glycol.Preferably, described method also comprises step:
(7) filtrate step (6) obtained, by rectifying separation, obtains ethylene glycol.
As one preferred embodiment, described synthetic method,
In described step (1) nitration mixture, the weight ratio of acetic acid and the vitriol oil is 1:0.74;
The reaction times of described step (2) is 30 minutes;
Described step (3), for cooling reaction solution is to 30 DEG C, adds 30% industrial lye and regulates pH to 2.5, filter, reclaim the itrated compound crystallization of separating out;
Described step (4) is that continuation liquid caustic soda is adjusted to pH to 10 ~ 12 by the filtrate control temperature of step (3) at 50 DEG C, separates out metronidazole crude product, and filter, drying obtains metronidazole crude product;
The filtrate of step (4) is regulated pH to 4 ~ 7 at 40 DEG C by described step (5), filters, and reclaims the secondary recovery itrated compound of separating out.
More effectively itrated compound can be reclaimed according to the method described above from metronidazole mother liquor, the acetic ester simultaneously obtained and the by product such as anhydrous sodium sulphate, ethylene glycol are all broad-spectrum industrial chemicals, thus achieve the recycling of resource, improve economic worth significantly.
The beneficial effect that the application can produce comprises:
1. formic acid large to equipment corrosion in traditional technology is changed into commercially available price is lower, the acetic acid of environmental protection more, improve the transformation efficiency of raw material, reduce unit consumption, increase product profit.
2. by adding the mode of alcohol, the acetic acid being used as liquid waste disposal in mother liquor is changed into easily separated go out acetic ester, not only turn waste into wealth, and make only there is single sulfuric acid in mother liquor, the extraction facilitating inorganic salt in waste liquid is reclaimed, and solves in the waste water that traditional technology produces because being difficult to the problem of separation containing plurality of inorganic salt.
3. pair mother liquor carries out third time neutralization, the complete itrated compound of unreacted can be made to obtain more effective recovery, not only saved resource, be more conducive to environmental protection.
4. utilize metabisulfite solution crystallization more than 32.4 DEG C to go out anhydrous sodium sulphate, utilize the high boiling point of ethylene glycol 197.3 DEG C, the sodium sulfate of existence a large amount of in waste liquid and ethylene glycol are extracted efficiently, makes resource obtain reasonable recycle, achieve environmental protection.
5. whole invented technology reaction conditions is gentle, and operation is simple, with low cost.
The invention provides the environmental protection method of a kind of metronidazole synthesis, adopt the method, constantly on raw material, use environmental protection more and the new raw material little to equipment corrosion, and by further for whole operation derivatize, can reduce the content of various pollutant in waste water significantly, effectively reduce environmental protection pressure, novel process can reclaim the complete itrated compound of unreacted further simultaneously, and the higher anhydrous sodium sulphate solid of purity can be obtained, the derivatize such as acetic ester, ethylene glycol product.Saved raw material significantly, reduced production cost, and whole novel process step is simple, easy to operate.
Embodiment
Below in conjunction with specific examples, technical scheme of the present invention is described further, contributes to understanding the present invention, but do not limit content of the present invention.Term used in the present invention, except as otherwise noted, generally has the implication that those of ordinary skill in the art understand usually.
Embodiment 1 is reacted
Joined by the industrial acetic acid of 400g99% in 10L reactor, under stirring cooling, instill 98% vitriol oil 300g, control temperature is at 30 DEG C.After nitration mixture prepares, add 580g2-5-nitro imidazole, heating for dissolving.Alternately pass into oxyethane (total amount 370g) at 90 DEG C and drip 98% vitriol oil (total amount 100g), logical complete, insulation reaction 30 minutes, reacted reaction solution is designated as reaction solution 1
#.
Embodiment 2 ~ 5 is reacted
Operating process is identical with embodiment 1, and reacted reaction solution is designated as reaction solution 2 respectively
#~ reaction solution 5
#, difference is proportioning raw materials and reaction conditions, as shown in Table 1 below.
Table 1 reaction raw materials and condition
Embodiment 6 is separated
Embodiment 1 after completion of the reaction, the reaction solution 1 obtained
#be cooled to 50 DEG C, add 200g methyl alcohol, 60 DEG C of backflows 1 hour, Distillation recovery methyl acetate 353g (purity 92.1%).Add 30% industrial lye at 30 DEG C and regulate about pH to 2.5, separate out the crystallization of itrated compound.Filter, itrated compound 304g is once reclaimed in drying.Filtrate control temperature is at 50 DEG C, and continuation liquid caustic soda is adjusted to pH to 11, separates out metronidazole crude product, and filter, drying obtains metronidazole crude product 315g (content 99.1%, fusing point 157.6 ~ 159.2 DEG C).Filtrate regulates pH to 5-7 further at 40 DEG C, separates out secondary recovery itrated compound 20g.Filtrate carrying out is evaporated to about 1/4 of original volume, crystallization at 35 DEG C, filters, dry anhydrous sodium sulphate 476g (content 98.1%).Filtrate is separated by rectifier unit, obtains ethylene glycol 39g (content 92.6%).
The reaction solution 2 that embodiment 2 ~ 5 obtains
#~ reaction solution 5
#lock out operation and reaction solution 1
#identical, difference be operational condition and materials, refer to table 2.
Table 2
The above, only several embodiments of the application, not any type of restriction is done to the application, although the application discloses as above with preferred embodiment, but and be not used to limit the application, any those skilled in the art, not departing from the scope of technical scheme, utilize the technology contents of above-mentioned announcement to make a little variation or modify and be all equal to equivalent case study on implementation, all belong within the scope of technical scheme.
Claims (10)
1. a synthetic method for metronidazole, comprises the following steps:
(1) acetic acid and sulfuric acid mixed according to the ratio of weight ratio 1:0.5 ~ 5 and be made into nitration mixture, add 2-5-nitro imidazole, heating for dissolving, the weight ratio of 2-5-nitro imidazole and described nitration mixture is 1:0.5 ~ 4;
(2) in 90 ~ 100 DEG C of systems obtained to step (1), pass into oxyethane and the vitriol oil, react 10 ~ 60 minutes;
(3) step (2) reacted reaction solution is cooled to 10 ~ 40 DEG C, adds liquid caustic soda and regulate pH to 2 ~ 4, filter, reclaim the itrated compound crystallization of separating out;
(4) by the filtrate of step (3) at 20 ~ 60 DEG C, regulate pH to 10 ~ 12 with liquid caustic soda, separate out metronidazole crude product, filter, drying obtains metronidazole crude product.
2. synthetic method according to claim 1, wherein the weight ratio of step (2) ethylene oxide and 2-5-nitro imidazole is 1:0.8 ~ 3.
3. synthetic method according to claim 1, wherein the weight ratio of step (2) ethylene oxide and the vitriol oil is 1:0.1 ~ 1.
4. synthetic method according to claim 1, the reaction times of described step (2) is 20 ~ 40 minutes.
5. synthetic method according to claim 1, wherein step (2) is for alternately passing into oxyethane at 90 ~ 100 DEG C and drip 98% vitriol oil, logical complete, insulation reaction 10 ~ 60 minutes, the total amount of its ethylene oxide and the weight ratio of 2-5-nitro imidazole are 1:0.8 ~ 3; The weight ratio of 98% vitriol oil of oxyethane and dropping is 1:0.1 ~ 1.
6. synthetic method according to claim 1, wherein step (3) is, cooling reaction solution, to 20 ~ 50 DEG C, adds lower alcohol, 60 ~ 80 DEG C of backflows 0.5 ~ 2 hour, Distillation recovery acetic ester; Be cooled to 20 ~ 40 DEG C again, add liquid caustic soda and regulate pH to 2 ~ 3, filter, reclaim the itrated compound crystallization of separating out.
7. synthetic method according to claim 6, the weight ratio of the acetic acid of described lower alcohol and step (1) is 1:0.5 ~ 1.
8. synthetic method according to claim 6, described lower alcohol is selected from the one in methyl alcohol, ethanol or Virahol.
9. synthetic method according to claim 1, also comprises step:
(5) filtrate step (4) obtained regulates pH to 4 ~ 7 at 30 ~ 50 DEG C, filters, and reclaims the secondary recovery itrated compound of separating out;
(6) filtrate the carrying out that step (5) obtains is evaporated to about 1/4 of original volume, at 35 ~ 100 DEG C of crystallizatioies, filters, dry anhydrous sodium sulphate;
(7) filtrate step (6) obtained, by rectifying separation, obtains ethylene glycol.
10. synthetic method according to claim 9, is characterized in that,
In described step (1) nitration mixture, the weight ratio of acetic acid and the vitriol oil is 1:0.74;
The reaction times of described step (2) is 30 minutes;
Described step (3), for cooling reaction solution is to 30 DEG C, adds 30% industrial lye and regulates pH to 2.5, filter, reclaim the itrated compound crystallization of separating out;
Described step (4) is that continuation liquid caustic soda is adjusted to pH to 10 ~ 12 by the filtrate control temperature of step (3) at 50 DEG C, separates out metronidazole crude product, and filter, drying obtains metronidazole crude product;
The filtrate of step (4) is regulated pH to 4 ~ 7 at 40 DEG C by described step (5), filters, and reclaims the secondary recovery itrated compound of separating out.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107325054A (en) * | 2017-07-17 | 2017-11-07 | 黄冈师范学院 | The method of accessory substance recycled in metronidazole production process |
| CN107857732A (en) * | 2017-12-21 | 2018-03-30 | 黄冈师范学院 | Formic acid glycol ester is applied mechanically in a kind of production of metronidazole method, the method for realizing the device and application of this method device |
| CN107879983A (en) * | 2017-12-21 | 2018-04-06 | 黄冈师范学院 | A kind of metronidazole synthetic method of metronidazole synthesizer and the application device |
| CN108203380A (en) * | 2016-12-19 | 2018-06-26 | 曾舟华 | The method that formic acid solvent is recycled in metronidazole production process |
| CN108203411A (en) * | 2016-12-19 | 2018-06-26 | 曾舟华 | A kind of method of high-pressure synthesis metronidazole |
| CN108276340A (en) * | 2018-03-23 | 2018-07-13 | 兰亚朝 | Produce the synthetic method of metronidazole API |
| CN109293573A (en) * | 2018-11-29 | 2019-02-01 | 黄冈师范学院 | The method, apparatus and application of ethylene glycol by-product recycled in metronidazole production |
| CN109776425A (en) * | 2019-03-25 | 2019-05-21 | 河池市金兴生物科技有限公司 | The conversion recyclable device of formic acid solvent in metronidazole production process |
| CN110172039A (en) * | 2018-05-11 | 2019-08-27 | 武汉武药制药有限公司 | A kind of method of solid acid catalysis synthesis metronidazole |
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Cited By (12)
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| CN108203380A (en) * | 2016-12-19 | 2018-06-26 | 曾舟华 | The method that formic acid solvent is recycled in metronidazole production process |
| CN108203411A (en) * | 2016-12-19 | 2018-06-26 | 曾舟华 | A kind of method of high-pressure synthesis metronidazole |
| CN107325054A (en) * | 2017-07-17 | 2017-11-07 | 黄冈师范学院 | The method of accessory substance recycled in metronidazole production process |
| CN107857732A (en) * | 2017-12-21 | 2018-03-30 | 黄冈师范学院 | Formic acid glycol ester is applied mechanically in a kind of production of metronidazole method, the method for realizing the device and application of this method device |
| CN107879983A (en) * | 2017-12-21 | 2018-04-06 | 黄冈师范学院 | A kind of metronidazole synthetic method of metronidazole synthesizer and the application device |
| CN107879983B (en) * | 2017-12-21 | 2023-09-19 | 黄冈师范学院 | Metronidazole synthesis device and Metronidazole synthesis method using same |
| CN107857732B (en) * | 2017-12-21 | 2024-05-28 | 黄冈师范学院 | Method for applying ethylene formate in metronidazole production, device for realizing method and method for applying device |
| CN108276340A (en) * | 2018-03-23 | 2018-07-13 | 兰亚朝 | Produce the synthetic method of metronidazole API |
| CN110172039A (en) * | 2018-05-11 | 2019-08-27 | 武汉武药制药有限公司 | A kind of method of solid acid catalysis synthesis metronidazole |
| CN109293573A (en) * | 2018-11-29 | 2019-02-01 | 黄冈师范学院 | The method, apparatus and application of ethylene glycol by-product recycled in metronidazole production |
| CN109293573B (en) * | 2018-11-29 | 2023-10-27 | 黄冈师范学院 | Method, device and application for recycling ethylene glycol byproducts in metronidazole production |
| CN109776425A (en) * | 2019-03-25 | 2019-05-21 | 河池市金兴生物科技有限公司 | The conversion recyclable device of formic acid solvent in metronidazole production process |
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Inventor after: Zhao Taotao Inventor after: Pi Jinhong Inventor after: Yang Shihong Inventor after: Dong Jianqiang Inventor after: Rao Kunlun Inventor after: Li Binbin Inventor after: Deng Jun Inventor after: Zhang Qi Inventor before: Pi Jinhong Inventor before: Zhao Taotao Inventor before: Yang Shihong Inventor before: Dong Jianqiang Inventor before: Rao Kunlun Inventor before: Li Binbin Inventor before: Deng Jun Inventor before: Zhang Qi |
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