CN102086174B - Production method of 2,3-dichloropyridine - Google Patents
Production method of 2,3-dichloropyridine Download PDFInfo
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- CN102086174B CN102086174B CN2011100540218A CN201110054021A CN102086174B CN 102086174 B CN102086174 B CN 102086174B CN 2011100540218 A CN2011100540218 A CN 2011100540218A CN 201110054021 A CN201110054021 A CN 201110054021A CN 102086174 B CN102086174 B CN 102086174B
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Abstract
The invention relates to a production method of 2,3-dichloropyridine, solving the problem that byproducts are easily generated through 2-position chlorination reaction so as to cause the final product quality to be instable, for example, intermediate purification is carried out but yield and environment are influenced, and the working efficiency is reduced. The production method of the 2,3-dichloropyridine comprises the following steps: 1) carrying out degradation reaction: hydrolyzing 2-chloro nicotinamide used as a starting material, and carrying out solid-liquid separation to obtain 2-chlorine-3-aminopyridine; and (2) successively carrying out diazotization reaction and 3-position chlorination reaction: successively carrying out diazotization reaction and 3-position chlorination reaction on 2-chlorine-3-aminopyridine to obtain 2,3-dichloropyridine. The production method has the beneficial effects that (1) the difficulty that the byproducts are easily generated because 2-position chlorination is successfully avoided, thereby ensuring the quality of the intermediate product 2-chlorine-3-aminopyridine; and (2) because the intermediate product 2-chlorine-3-aminopyridine is not dissolved in strong basic aqueous solution, the product can be directly taken out by vacuum filtration, and is easy to purify.
Description
Technical field
The present invention relates to a kind of 2, the working method of 3-dichloropyridine.
Background technology
2, the 3-dichloropyridine is a kind of important fine-chemical intermediate, is widely used in medicine and pesticide field, particularly along with the listing of O-formammidotiazol-benzamide sterilant, more becomes the research focus as these article synthetic technology of key intermediate.But its representational document has only two patents:
One of which, the PCT International Application No. WO 2005070888 of disclosed du pont company application on August 4 in 2005; Its basic characteristic is: with vitamin PP as starting raw material; Obtain containing the solution of 3-EL-970 through degraded, thickening, with salt acid elution residue; After feeding dry hydrogen chloride gas raising acid concentration again, controlled temperature drips ydrogen peroxide 50 and carries out 2 chlorination reactions, regulates different pH values then again; Use solvent wash ten stage by stage for several times, with the purification intermediates; Thereafter diazotization and 3 all reaction completion under the situation that organic solvent exists of chloro go out product with SX at last.Calculate comprehensive yield 50.11% of 4 steps from vitamin PP, the finished product, outward appearance is faint yellow, content (HPLC) 98%.
They are two years old; The patent CN100357272C that the applicant authorized on December 26th, 2007 discloses a kind of 2; The compound method of 3-dichloropyridine, its basic characteristic is: as starting raw material, obtain the finished product through 2 chlorinations, diazotization, 3 chloros with the 3-EL-970.Advantage than Du Pont technology is mainly reflected in four aspects: the first, control properly, and intermediate product must not pass through purification, has increased substantially working efficiency, has reduced pollution; The second, reaction process is not with an organic solvent; The 3rd, the yield that calculates from the 3-EL-970 equally improves more than 5 percentage points than Du Pont; The 4th, product appearance white, content 99% (HPLC).
But,, also exist 2 chlorination controls to require too high shortcoming, like the careless slightly difficult quality guarantee that will cause the finished product though Du Pont's patent that this invention is compared is significantly improved.
Summary of the invention
The invention provides a kind of 2; The working method of 3-dichloropyridine; Solved a difficult problem of the prior art: promptly 2 chlorination reactions very easily produce by product, cause end product quality stable inadequately, as carry out intermediate purification and can influence yield and environment again and reduce work efficiency.
Said 2, the working method of 3-dichloropyridine may further comprise the steps:
1) DeR: with the 2-chloro-nicotinamide is starting raw material, and in alkaline aqueous solution, by the hydrolysis of 2-chloro-nicotinamide, solid-liquid separation obtains 2-chloro-3-EL-970 then;
2) carry out diazotization reaction and 3 chlorinations successively: make 2-chloro-3-EL-970 carry out diazotization and 3 chlorinations successively, obtain 2, the 3-dichloropyridine.
Preferred steps 1) detailed process is: with the 2-chloro-nicotinamide is starting raw material, adds the water of 4～6 times of quality of starting raw material, the stirring at normal temperature dissolving; Be cooled to 0～5 ℃, drip the chlorine bleach liquor, 0～5 ℃ of controlled temperature; Finish and drip 2～4 times to 30% aqueous sodium hydroxide solution of starting raw material quality, 0～5 ℃ of same controlled liq temperature finishes; Slowly be warming up to 80～85 ℃, insulation reaction 2 hours is lowered the temperature, is obtained 2-chloro-3-EL-970 through solid-liquid separation.Said 2-chloro-nicotinamide is commercially available industrial goods.The molar weight of Youxiaolin is 1.2 times of 2-chloro-nicotinamide among the preferred said chlorine bleach liquor.Preferred used chlorine bleach liquor's concentration >=10%.The dropping time of Youxiaolin is 2～2.5 hours.The time of dropwise liquid is 1.5～2 hours.
Preferred steps 2) detailed process of diazotization reaction is described in: 2-chloro-3-EL-970 is with 10～12 times of concentrated hydrochloric acid stirring at normal temperature dissolvings to the starting raw material quality; Be cooled to below 0 ℃; The sodium nitrite solution of mol such as dropping and starting raw material amount; Carry out diazotization reaction, Sodium Nitrite finishes back insulation 0.5～1 hour.It is 25%～30% the aqueous solution that sodium nitrite solution is preferably mass percent concentration.The sodium nitrite solution dropping time was preferably in 2 hours.
Preferred steps 2) detailed process of 3 chlorinations is described in: the reacting liquid temperature after the diazotization reaction is controlled at below 0 ℃; The cuprous chloride that drips 0.15 times of molar weight of starting raw material is dissolved in the mixed solution of the concentrated hydrochloric acid composition of 1.2 times of quality of starting raw material, is incubated half a hour at least after dropwising.
Reaction obtains 2, can adopt known method to purify behind the 3-dichloropyridine, as use dichloromethane extraction, and the solvent of removing in the extraction liquid obtains 2, the 3-dichloropyridine.
The present invention on the prior art basis, through design technology method again, the deficiency before having solved, and can produce following beneficial effect:
(1) owing to use the 2-chloro-nicotinamide, successfully avoided 2 chlorinations and very easily produced the difficult problem of side reaction, guaranteed the quality of intermediate product 2-chloro-3-EL-970, and then laid a good foundation for the assurance of end product quality as starting raw material.
(2) also owing to use the 2-chloro-nicotinamide as starting raw material, used the degraded operation equally, because the intermediate product 2-chloro-3-EL-970 of gained is insoluble to strong alkaline aqueous solution, product directly suction filtration takes out.
And if use vitamin PP as the degraded raw material because gained intermediate product 3-EL-970 is water-soluble fine, take out extremely difficultly, literature method has two:
One of which; The method that Du Pont's technology adopts is: to subacidity, decompression steams moisture content to doing with hydrochloric acid conditioned reaction liquid in elder generation, and the intermediate product that will remain in the sodium-chlor again washes out with Hydrogen chloride; For guaranteeing the hydrogen cloride concentration of next step reaction solution, also must in reaction solution, feed dry hydrogen chloride gas.Clearly, this method energy consumption is big, and complex operation, Working environment are also bad.
Its two, have bibliographical information to make extraction agent with methylene dichloride, continuous extraction is more than 20 hours in special extraction plant.Obviously, this method has been used organic solvent, has increased cost and has also polluted environment, the more important thing is that the extraction efficiency of this method is very low, is difficult to satisfy industrial production requirement.
Embodiment
In following examples, used 2-chloro-nicotinamide is commercially available industrial goods, purity＞98% (HPLC).
Embodiment 1:
In the 1000ml reaction flask, add 2-chloro-nicotinamide 39.1g (0.25mol), water 160ml, the stirring at normal temperature dissolving.Cryosel is bathed cooling, and 1 ℃ begins to drip 10% Youxiaolin 223.5g, 0 ℃～5 ℃ of process control temps, 2 hours times spent.Temperature is 4 ℃ when finishing, and drips 30% sodium hydroxide solution 80g again, 1.5 hours times spent, 0 ℃～5 ℃ of process control temps.Temperature is 3 ℃ when finishing, and uses water-bath instead and slowly heats up, and reaches 80 ℃ after 45 minutes, later in 80～85 ℃ of insulation reaction 2 hours.5 ℃ of temperature, suction filtration, oven dry were stirred in cooling at a slow speed 5 hours.Get off-white color solid 2-chloro-3-EL-970 27.95g (yield 87%).
Above-mentioned intermediate product is joined in the 1000ml reaction flask, add concentrated hydrochloric acid 391g (mass percent concentration is more than 31%, down together), the stirring at normal temperature dissolving.Use cryosel instead and bathe and to be cooled to-3 ℃, begin to drip the 18.0g industrial sodium nitrite solution that (purity >=96%)+water 42ml processes, 65 minutes times spent, process control temp＜0 ℃.Finish equality of temperature reaction 30 minutes.
To expect temperature drop again to-5 ℃, and drip with 45 minutes and be dissolved in the catalyst solution of forming in the 47g concentrated hydrochloric acid that warm-5 ℃～-2 ℃ of control material finishes-2 ℃～0 ℃ insulation reaction 1 hour by the 3.75g cuprous chloride.Use water-bath instead, let the material temperature be back to room temperature.Each with methylene dichloride 50ml extracted twice, combining extraction liquid spends the night with anhydrous sodium sulfate drying, and the filtering siccative is evaporated to driedly, promptly gets white object product 23.90g (three go on foot comprehensive yield 64.6%), content 99.53%.
Embodiment 2:
In the 1000ml reaction flask, add 2-chloro-nicotinamide 39.1g (0.25mol), water 190ml, the stirring at normal temperature dissolving.Cryosel is bathed cooling, and 0 ℃ begins to drip 10% Youxiaolin 223.5g, 0 ℃～5 ℃ of process control temps, 2.5 hours times spent.Temperature is 2 ℃ when finishing, and drips 30% sodium hydroxide solution 100g again, 1.5 hours times spent, 0 ℃～5 ℃ of process control temps.Temperature is 5 ℃ when finishing, and uses water-bath instead and slowly heats up, and reaches 80 ℃ after 50 minutes, later in 80～85 ℃ of insulation reaction 2 hours.Cooling, stirred overnight at a slow speed, 4 ℃ of temperature, suction filtration, oven dry.Get off-white color solid 2-chloro-3-EL-970 28.35g (yield 88.2%).
Above-mentioned intermediate product is joined in the 1000ml reaction flask, add the hydrochloric acid 420g of 31% above concentration, the stirring at normal temperature dissolving.Use cryosel instead and bathe and to be cooled to-3 ℃, begin to drip the solution that the 18.0g industrial sodium nitrite+water 42ml processes, 54 minutes times spent, process control temp＜0 ℃.Finish equality of temperature reaction 30 minutes.
To expect temperature drop again to-5 ℃, and drip with 50 minutes and be dissolved in the catalyst solution of forming in the 47g hydrochloric acid that warm-5 ℃～-2 ℃ of control material finishes-2 ℃～0 ℃ insulation reaction 1 hour by the 3.75g cuprous chloride.Use water-bath instead, let the material temperature be back to room temperature.Each with methylene dichloride 50ml extracted twice, combining extraction liquid spends the night with anhydrous sodium sulfate drying, and the filtering siccative is evaporated to driedly, promptly get white object product 24.33g (three go on foot merging yield 65.8%), content 99.64%.
Embodiment 3:
In the 1000L reaction kettle, add 2-chloro-nicotinamide 39.1Kg (0.25kmol), water 190l, the stirring at normal temperature dissolving.Cryosel is bathed cooling, and 0 ℃ begins to drip 10% Youxiaolin 223.5kg, 0 ℃～5 ℃ of process control temps, 132 minutes times spent.Temperature is 3 ℃ when finishing, and drips 30% sodium hydroxide solution 100Kg again, 91 minutes times spent, 0 ℃～5 ℃ of process control temps.Temperature is 4 ℃ when finishing, and uses jacket steam instead and slowly heats up, and reaches 80 ℃ after 54 minutes, later in 80～85 ℃ of insulation reaction 2 hours.Chuck is used instead and is used icy salt solution behind water for cooling to the near ambient temperature again instead and continue cooling, stirs 0 ℃～5 ℃ numbers of holding temperature hour, suction filtration, oven dry.Get off-white color solid 2-chloro-3-EL-970 28.74Kg (yield 89.42%).
Above-mentioned intermediate product is joined in the 1000L reaction kettle, add the hydrochloric acid 420Kg of 31% above concentration, the stirring at normal temperature dissolving.Use cryosel instead and bathe and to be cooled to-5 ℃, begin to drip the solution that the 18Kg industrial sodium nitrite+water 42l processes, 105 minutes times spent, process control temp＜0 ℃.Finish equality of temperature reaction 30 minutes.
To expect temperature drop again to-5 ℃, and drip with 55 minutes and be dissolved in the catalyst solution of forming in the 50Kg hydrochloric acid that warm-5 ℃～-2 ℃ of control material finishes-2 ℃～0 ℃ insulation reaction 1 hour by the 3.75Kg cuprous chloride.Use water-bath instead, let the material temperature be back to room temperature.Each with methylene dichloride 50l extracted twice, combining extraction liquid spends the night with anhydrous sodium sulfate drying, and the filtering siccative is evaporated to driedly, promptly get white object product 25.34Kg (three go on foot merging yield 68.5%), content 99.55%.
Embodiment 4:
In the 1000L reaction kettle, add 2-chloro-nicotinamide 39.1Kg (0.25kmol), water 220l, the stirring at normal temperature dissolving.Cryosel is bathed cooling, and 0 ℃ begins to drip 10% Youxiaolin 223.5kg, 0 ℃～5 ℃ of process control temps, 127 minutes times spent.Temperature is 5 ℃ when finishing, and drips 30% sodium hydroxide solution 150Kg again, 97 minutes times spent, 0 ℃～5 ℃ of process control temps.Temperature is 3 ℃ when finishing, and uses jacket steam instead and slowly heats up, and reaches 80 ℃ after 62 minutes, later in 80～85 ℃ of insulation reaction 2 hours.Chuck is used instead and is used icy salt solution behind water for cooling to the near ambient temperature again instead and continue cooling, stirs 0 ℃～5 ℃ numbers of holding temperature hour, and suction filtration gets the wet article of off-white color solid 2-chloro-3-EL-970.
Above-mentioned intermediate product is joined in the 1000L reaction kettle, add the hydrochloric acid 420Kg of 31% above concentration, the stirring at normal temperature dissolving.Use cryosel instead and bathe and to be cooled to-5 ℃, begin to drip the solution that the 18Kg industrial sodium nitrite+water 42l processes, 100 minutes times spent, process control temp＜0 ℃.Finish equality of temperature reaction 30 minutes.
To expect temperature drop again to-5 ℃, and drip with 67 minutes and be dissolved in the catalyst solution of forming in the 50Kg hydrochloric acid that warm-5 ℃～-2 ℃ of control material finishes-2 ℃～0 ℃ insulation reaction 1 hour by the 3.75Kg cuprous chloride.Use water-bath instead, let the material temperature be back to room temperature.Each with methylene dichloride 50l extracted twice, combining extraction liquid spends the night with anhydrous sodium sulfate drying, and the filtering siccative is evaporated to driedly, promptly get white object product 25.59kg (three go on foot merging yield 69.20%), content 99.72%.
Claims (7)
1. one kind 2, the working method of 3-dichloropyridine is characterized in that may further comprise the steps:
1) DeR: with the 2-chloro-nicotinamide is starting raw material, adds the water of 4～6 times of quality of starting raw material, the stirring at normal temperature dissolving; Be cooled to 0～5 ℃, drip the chlorine bleach liquor, 0～5 ℃ of controlled temperature; Finish and drip 2～4 times to 30% aqueous sodium hydroxide solution of starting raw material quality, 0～5 ℃ of same controlled liq temperature finishes; Slowly be warming up to 80～85 ℃, insulation reaction 2 hours is lowered the temperature, is obtained 2-chloro-3-EL-970 through solid-liquid separation;
2) carry out diazotization reaction and 3 chlorinations successively: make 2-chloro-3-EL-970 carry out diazotization and 3 chlorinations successively, obtain 2, the 3-dichloropyridine.
2. as claimed in claim 12, the working method of 3-dichloropyridine is characterized in that, the molar weight of said Youxiaolin is 1.2 times of 2-chloro-nicotinamide.
According to claim 1 or claim 22; The working method of 3-dichloropyridine is characterized in that step 2) described in the detailed process of diazotization reaction be: 2-chloro-3-EL-970 is with 10～12 times of concentrated hydrochloric acid stirring at normal temperature dissolvings to the starting raw material quality; Be cooled to below 0 ℃; The sodium nitrite solution of mol such as dropping and starting raw material amount carries out diazotization reaction, and Sodium Nitrite finishes back insulation 0.5～1 hour.
4. as claimed in claim 32, the working method of 3-dichloropyridine is characterized in that step 2) in sodium nitrite solution be 25%～30% the aqueous solution.
5. as claimed in claim 32, the working method of 3-dichloropyridine is characterized in that step 2) in the sodium nitrite solution dropping time be in 2 hours.
According to claim 1 or claim 22; The working method of 3-dichloropyridine; It is characterized in that; Step 2) detailed process of 3 chlorinations is described in: the reacting liquid temperature after the diazotization reaction is controlled at below 0 ℃, and the cuprous chloride that drips 0.15 times of molar weight of starting raw material is dissolved in the mixed solution of the concentrated hydrochloric acid composition of 1.2 times of quality of starting raw material, is incubated half a hour at least after dropwising.
According to claim 1 or claim 22, the working method of 3-dichloropyridine is characterized in that, used chlorine bleach liquor's concentration >=10% in the step 1).
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| CN103420903A (en) * | 2013-09-03 | 2013-12-04 | 天津安锦科技发展有限公司 | Method for synthesizing 5-Bromo-2, 4-dichloropyridine |
| CN103570609B (en) * | 2013-10-28 | 2015-11-18 | 南通天泽化工有限公司 | A kind of preparation method of 2,3-dichloropyridine |
| CN104926715A (en) * | 2015-06-03 | 2015-09-23 | 安徽绩溪县徽煌化工有限公司 | Method for preparing 2,3-dichloropyridine |
| CN106748980A (en) * | 2015-11-22 | 2017-05-31 | 宁夏际华环境安全科技有限公司 | A kind of dichloropyridine production technology |
| CN105399663B (en) * | 2015-12-23 | 2018-09-14 | 山东天信化工有限公司 | A method of preparing 2,3- dichloropyridines |
| CN107337636B (en) * | 2017-07-20 | 2020-03-27 | 凯莱英医药集团（天津）股份有限公司 | Continuous diazotization reaction of pyridine compound and application thereof |
| CN108341776B (en) * | 2018-04-13 | 2021-04-09 | 北京金城泰尔制药有限公司沧州分公司 | Process for synthesizing chloroquinate |
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