CN102796051A - Preparation method of mequindox - Google Patents
Preparation method of mequindox Download PDFInfo
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- CN102796051A CN102796051A CN2012103336250A CN201210333625A CN102796051A CN 102796051 A CN102796051 A CN 102796051A CN 2012103336250 A CN2012103336250 A CN 2012103336250A CN 201210333625 A CN201210333625 A CN 201210333625A CN 102796051 A CN102796051 A CN 102796051A
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Abstract
The invention discloses a preparation method of mequindox, belonging to the field of medicine chemical industry. The preparation method comprises the following steps: carrying out redox reaction on o-nitroaniline and a sodium hypochlorite solution under alkaline conditions to obtain benzofurazan, and after the reaction finishes, and adding an organic solvent for extraction, thereby obtaining a benzofurazan organic solution; and adding a catalyst and acetylacetone into the benzofurazan organic solution to initiate condensation reaction, thereby obtaining the mequindox. The invention omits the steps of benzofurazan separation, storage, drying, transportation, addition, dissolution and the like, thereby saving the human resources, material resources and financial resources, reducing the loss of benzofurazan in the middle process, and lowering the production cost. Meanwhile, the invention separates water in the benzofurazan by extraction, thereby lowering the water content in the subsequent reaction and increasing the synthesis yield of mequindox.
Description
Technical field
The present invention relates to a kind of preparation method of mequindox, belong to field of medicine and chemical technology.
Background technology
Mequindox (methlacetylquinoxalinediode), chemical name: 3-methyl-2-ethanoyl quinoxaline-1,4-dioxide; Belong to broad spectrum antibiotic; Effect is better than positive bacteria to Gram-negative bacteria, and is stronger to the treponema effect, to yellow scour of piglet, dysentery characterized by white mucous stool, calf diarrhea; Typhus fever, avian pasteurella multocida, the white scour of chicken, chicken colibacillosis are all effective, are mainly used to swine dysentery and bacterial enteritis due to the treponema.
The preparation method of mequindox is in the prior art:
(1) o-Nitraniline and Youxiaolin carry out redox reaction under alkaline condition, obtain the benzo furazan, after centrifugal, washing, drying etc. are handled, get benzo furazan solid.
(2) in proportion a certain amount of benzo furazan solid and methyl ethyl diketone are dissolved in the methyl alcohol, heating for dissolving adds catalyzer then several times, and thermal response is after for some time, through filter or centrifugal after the mequindox solid, mequindox that must be purer after the drying.
Like application number is the compound method that 201110369320.0 patent discloses a kind of mequindox.This method is specially:
(1) preparation benzo furazan:
With the o-Nitraniline is raw material, and Youxiaolin is an oxygenant, in aqueous sodium hydroxide solution, carries out annulation, and control reaction temperature and is incubated more than 2 hours between 40～50 ℃, is cooled to the suction filtration of back below 30 ℃ then, obtains benzo furazan solid.
(2) preparation mequindox:
Benzo furazan solid and methyl ethyl diketone to obtain in the step (1) are raw material; With sodium acetate, anhydrous as catalyzer; In methyl alcohol, react, control reaction temperature is between 60～65 ℃, and 65 ℃ are incubated more than 3 hours down; Be cooled to the suction filtration of back below 30 ℃ then, obtain the mequindox solid phase prod.
Significantly; Step in patent 201110369320.0 (1) synthetic benzo furazan solid need pass through steps such as storage, drying, transhipment and just be used in the step (2); And need estimation benzo furazan solid water cut, calculate the charging capacity of benzo furazan again according to water cut.
The contriver finds that there is following problem at least in prior art in realizing process of the present invention:
1, in the prior art by behind the synthetic benzo furazan of o-Nitraniline, need through separate, store, dry, step such as transport, feed intake, pilot process can cause the waste of benzo furazan, and needs extra human and material resources and financial resources, has increased production cost.
2, the low drying that is difficult for of benzo furazan fusing point can cause wherein having the moisture content about 10%, and the existence of water can influence the degree that the reaction of synthesis of acetyl first quinoline is carried out, and the yield of synthesis of acetyl first quinoline is reduced.Simultaneously, contained non-quantitative moisture makes its charging capacity be difficult for accurately estimation in the benzo furazan, causes the waste of raw material easily, influences production cost.
3, the benzo furazan then is prone in the drying process produce impurity to thermally labile, has increased the side reaction in the condensation reaction, has reduced the quality of product.
Summary of the invention
For reducing production costs, improve the yield and the quality product of synthesis of acetyl first quinoline, the present invention aims to provide a kind of preparation method of mequindox,
Wherein, the present invention is that the route of raw material synthesis of acetyl first quinoline is following with the o-Nitraniline:
Wherein, said technical scheme is following:
The embodiment of the invention provides a kind of preparation method of mequindox, and this method comprises:
(1) redox reaction takes place and obtains the benzo furazan in o-Nitraniline and chlorine bleach liquor under alkaline condition, and reaction is accomplished back adding organic solvent extraction and obtained benzo furazan organic solution;
(2) in said benzo furazan organic solution, add catalyzer and methyl ethyl diketone, take place to obtain mequindox after the condensation reaction.
Wherein, the temperature of reaction of redox reaction described in the step (1) is 15 ℃～80 ℃, and the reaction times is 3～10h.
Preferably, the temperature of reaction of redox reaction described in the step (1) is 20 ℃～70 ℃, and the reaction times is 3～6h.
More preferably, the temperature of reaction of redox reaction described in the step (1) is 50 ℃～60 ℃, and the reaction times is 4h.
Particularly, add organic solvent extraction after said reaction is accomplished and obtain benzo furazan organic solution, specifically comprise:
After said redox reaction is accomplished; Adding said organic solvent and stirring dissolves said benzo furazan fully; Change in the extraction plant and extract, get organic layer and obtain said benzo furazan organic solution, said volume of organic solvent is 1.5～4 times of said o-Nitraniline quality.
Wherein, organic solvent described in the step (1) comprises a kind of in toluene, YLENE, ETHYLE ACETATE, the butylacetate.
Preferably, organic solvent is a toluene described in the step (1).
Wherein, the temperature of reaction of condensation reaction described in the step (2) is 25 ℃～110 ℃, and the reaction times is 3～10h.
Preferably, the temperature of reaction of condensation reaction described in the step (2) is 30 ℃～100 ℃, and the reaction times is 4～6h.
More preferably, the temperature of reaction of condensation reaction described in the step (2) is 50 ℃～60 ℃, and the reaction times is 4～5h.
Wherein, Catalyzer comprises one or more in sodium methylate, sodium ethylate, sodium hydroxide, Pottasium Hydroxide, yellow soda ash, salt of wormwood, triethylamine, the diethylamine thanomin described in the step (2), and said catalyst consumption is 1.5%～5% of a said o-Nitraniline quality.
Preferably, catalyzer is sodium hydroxide or triethylamine described in the step (2), and said catalyst consumption is 1.5%～5% of a said o-Nitraniline quality.
The beneficial effect that the embodiment of the invention is brought is:
The benzo furazan that o-Nitraniline and Youxiaolin produce in the embodiment of the invention is without separating, but directly through adding organic solvent, extraction obtains benzo furazan organic solution, under the effect of catalyzer and methyl ethyl diketone react and obtain final product.The present invention saved the benzo furazan separation, storage, drying, transport, feed intake, step such as dissolving, saved human and material resources and financial resources and reduced the loss of benzo furazan in the pilot process, reduced production cost.Simultaneously, the present invention also through extracting and separating the moisture in the benzo furazan, reduced the content of water in the subsequent reactions, increased the yield of synthesis of acetyl first quinoline.The embodiment of the invention does not use common methyl alcohol as organic solvent, and has been to use organic solvents such as toluene, has solved mequindox labile problem in methyl alcohol, has improved the yield and the quality product of product.
Embodiment
Wherein, the proportioning of o-Nitraniline, liquid caustic soda, Youxiaolin and the methyl ethyl diketone that in producing mequindox, uses is known by those skilled in the art, and the embodiment of the invention has adopted wherein a kind of common proportioning, but not as qualification of the present invention.
Embodiment 1
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) is under 15 ℃ temperature; Insulation reaction 10 hours adds 80ml YLENE, stirs the benzo furazan that reaction is produced and dissolves fully, changes the 500ml separating funnel over to and leaves standstill 15 minutes; Divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds Pottasium Hydroxide 0.8g; Be warming up to 25 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 6 hours; Centrifugal, washing, drying, mequindox 65.8g, yield is 77.13%.
Embodiment 2
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) is under 20 ℃ temperature; Insulation reaction 10 hours adds 100ml toluene, stirs the benzo furazan that reaction is produced and dissolves fully, changes the 500ml separating funnel over to and leaves standstill 15 minutes; Divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds thanomin 2.7g, is warming up to 30 ℃; Drip methyl ethyl diketone 38.5g, added the back insulation reaction 10 hours, reduce to room temperature again; Centrifugal, washing, drying, mequindox 67.1g, yield is 78.65%.
Embodiment 3
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) is under 20 ℃ temperature; Insulation reaction 6.5 hours adds 200ml toluene, stirs 10 minutes, changes the 500ml separating funnel over to and leaves standstill 15 minutes; Divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds diethylamine 2g, is warming up to 65 ℃; Drip methyl ethyl diketone 38.5g, added the back insulation reaction 6 hours, reduce to room temperature again; Centrifugal, washing, drying, mequindox 68.3g, yield is 80.06%.
Embodiment 4
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 50 ℃; Insulation reaction 6 hours is cooled to below 40 ℃ again, adds 100ml ETHYLE ACETATE, stirs 10 minutes; Change the 500ml separating funnel over to and left standstill 15 minutes, divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds sodium hydroxide 1g; Be warming up to 50 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 4 hours, reduce to room temperature again; Suction filtration, washing, drying get mequindox 73.3g, and yield is 85.93%.
Embodiment 5
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 55 ℃; Insulation reaction 4 hours is cooled to below 40 ℃ again, adds 150ml toluene, stirs 10 minutes; Change the 500ml separating funnel over to and left standstill 15 minutes, divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds triethylamine 2g; Be warming up to 55 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 5 hours, reduce to room temperature again; Centrifugal, washing, drying, mequindox 74.2g, yield is 86.98%.
Embodiment 6
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 60 ℃; Insulation reaction 4 hours is cooled to below 40 ℃ again, adds the 120ml butylacetate, stirs 10 minutes; Change the 500ml separating funnel over to and left standstill 15 minutes, divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds sodium methylate 1.8g; Be warming up to 60 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 4.5 hours, reduce to room temperature again; Suction filtration, washing, drying get mequindox 71.1g, and yield is 83.34%.
Embodiment 7
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 70 ℃; Insulation reaction 3 hours is cooled to below 40 ℃ again, adds 200ml toluene, stirs 10 minutes; Change the 500ml separating funnel over to and left standstill 15 minutes, divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds sodium ethylate 1.5g; Be warming up to 100 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 3 hours, reduce to room temperature again; Centrifugal, washing, drying, mequindox 68.7g, yield is 80.53%.
Embodiment 8
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 80 ℃; Insulation reaction 3 hours is cooled to below 40 ℃ again, adds 216ml YLENE, stirs 10 minutes; Change the 500ml separating funnel over to and left standstill 15 minutes, divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds salt of wormwood 2g; Be warming up to 110 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 3 hours, reduce to room temperature again; Centrifugal, washing, drying, mequindox 66.5g, yield is 77.95%.
Embodiment 9
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 50 ℃; Insulation reaction 4 hours is cooled to below 40 ℃ again, adds 100ml toluene, stirs 10 minutes; Change the 500ml separating funnel over to and left standstill 15 minutes, divide and remove following water layer and mechanical impurity, remaining organic layer changes the 250ml there-necked flask over to, adds yellow soda ash 1.2g; Be warming up to 55 ℃, drip methyl ethyl diketone 38.5g, added the back insulation reaction 4 hours, reduce to room temperature again; Centrifugal, washing, drying, mequindox 70.7g, yield is 82.87%.
Embodiment (Comparative Examples)
In the 500ml there-necked flask, add the 54g o-Nitraniline, 18g alkali lye (30%), the Youxiaolin of 320g (available chlorine 10%～15%) slowly is warming up to 50 ℃; Insulation reaction 4 hours is cooled to below 40 ℃ again, centrifugal, washing; Obtain benzo furazan solid, the heavily about 58g of wet article, placement is dried in the shade.In the 250ml there-necked flask, add methyl alcohol 30g, the benzo furazan article 33.5g (content about 88%～92%) that wets adds methyl ethyl diketone 22.5g again; Stirring is warming up to 50 ℃, insulation reaction 2 hours, and gradation adds yellow soda ash 1.2g altogether; In 55 ℃ of insulation reaction 4 hours, reduce to room temperature more then, centrifugal, washing, drying; Get mequindox 39.5g, yield is 80.17%
Through the foregoing description 9 and Comparative Examples; Can find out in preparing the method for mequindox, adopt method of the present invention to be superior to existing method, the present invention is after o-Nitraniline and Youxiaolin generation redox reaction; Directly add organic solvent extraction and obtain benzo furazan organic solution; And need not separate and drying process, carry out condensation reaction again, the yield that can effectively improve synthesis of acetyl first quinoline with reduce production costs.Simultaneously, the present invention has also solved mequindox labile problem in methyl alcohol.
More than embodiments of the invention are specified, but the present invention is not limited to the foregoing description, in the ken that those of ordinary skills possessed, can also make various variations not breaking away under the aim prerequisite of the present invention.
Claims (10)
1. the preparation method of a mequindox is characterized in that, said method comprises:
(1) redox reaction takes place and obtains the benzo furazan in o-Nitraniline and chlorine bleach liquor under alkaline condition, and reaction is accomplished back adding organic solvent extraction and obtained benzo furazan organic solution;
(2) in said benzo furazan organic solution, add catalyzer and methyl ethyl diketone, take place to obtain mequindox after the condensation reaction.
2. preparation method according to claim 1 is characterized in that, the temperature of reaction of redox reaction described in the step (1) is 15 ℃～80 ℃, and the reaction times is 3～10h.
3. preparation method according to claim 1 is characterized in that, the temperature of reaction of redox reaction described in the step (1) is 50 ℃～60 ℃, and the reaction times is 4h.
4. preparation method according to claim 1 is characterized in that, adds organic solvent extraction after said reaction is accomplished and obtains benzo furazan organic solution, specifically comprises:
After said redox reaction is accomplished; Adding said organic solvent and stirring dissolves said benzo furazan fully; Change in the extraction plant and extract, get organic layer and obtain said benzo furazan organic solution, said volume of organic solvent is 1.5～4 times of said o-Nitraniline quality.
5. according to claim 1 or 4 described preparing methods, it is characterized in that organic solvent described in the step (1) comprises a kind of in toluene, YLENE, ETHYLE ACETATE, the butylacetate.
6. according to claim 1 or 4 described preparing methods, it is characterized in that organic solvent is a toluene described in the step (1).
7. preparation method according to claim 1 is characterized in that, the temperature of reaction of condensation reaction described in the step (2) is 25 ℃～110 ℃, and the reaction times is 3～10h.
8. preparation method according to claim 1 is characterized in that, the temperature of reaction of condensation reaction described in the step (2) is 50 ℃～60 ℃, and the reaction times is 4～5h.
9. preparation method according to claim 1; It is characterized in that; Catalyzer comprises one or more in sodium methylate, sodium ethylate, sodium hydroxide, Pottasium Hydroxide, yellow soda ash, salt of wormwood, triethylamine, diethylamine, the thanomin described in the step (2), and said catalyst consumption is 1.5%～5% of a said o-Nitraniline quality.
10. preparation method according to claim 1 is characterized in that, catalyzer is sodium hydroxide or triethylamine described in the step (2), and said catalyst consumption is 1.5%～5% of a said o-Nitraniline quality.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103420926A (en) * | 2013-06-07 | 2013-12-04 | 华中农业大学 | Chemical synthetic method of four main metabolites of quinocetone |
| CN103420929A (en) * | 2012-12-17 | 2013-12-04 | 华中农业大学 | Preparation method for tritium or deuterium labeled mequindox |
| CN107793372A (en) * | 2017-06-22 | 2018-03-13 | 北京立时达药业有限公司 | A kind of synthetic method of mequindox |
| CN109251178A (en) * | 2018-11-23 | 2019-01-22 | 河北美荷药业有限公司 | A kind of preparation method of mequindox |
| CN110317178A (en) * | 2019-07-22 | 2019-10-11 | 浙江科泓企业管理咨询有限公司 | A kind of mequindox novel method for synthesizing |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103420929A (en) * | 2012-12-17 | 2013-12-04 | 华中农业大学 | Preparation method for tritium or deuterium labeled mequindox |
| CN103420929B (en) * | 2012-12-17 | 2016-05-11 | 华中农业大学 | The preparation method of tritium or deuterium-labeled mequindox |
| CN103420926A (en) * | 2013-06-07 | 2013-12-04 | 华中农业大学 | Chemical synthetic method of four main metabolites of quinocetone |
| CN103420926B (en) * | 2013-06-07 | 2016-05-11 | 华中农业大学 | The chemical synthesis process of four kinds of metabolites of quinocetone |
| CN107793372A (en) * | 2017-06-22 | 2018-03-13 | 北京立时达药业有限公司 | A kind of synthetic method of mequindox |
| CN109251178A (en) * | 2018-11-23 | 2019-01-22 | 河北美荷药业有限公司 | A kind of preparation method of mequindox |
| CN109251178B (en) * | 2018-11-23 | 2020-08-25 | 河北美荷药业有限公司 | Preparation method of mequindox |
| CN110317178A (en) * | 2019-07-22 | 2019-10-11 | 浙江科泓企业管理咨询有限公司 | A kind of mequindox novel method for synthesizing |
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Application publication date: 20121128 |