CN105461622A - Method for preparing 4-amino-3,6-dichloropicolinic acid by reducing 4-amino-3,5,6-trichloropicolinic acid - Google Patents
Method for preparing 4-amino-3,6-dichloropicolinic acid by reducing 4-amino-3,5,6-trichloropicolinic acid Download PDFInfo
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- CN105461622A CN105461622A CN201510990091.2A CN201510990091A CN105461622A CN 105461622 A CN105461622 A CN 105461622A CN 201510990091 A CN201510990091 A CN 201510990091A CN 105461622 A CN105461622 A CN 105461622A
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- amino
- acid
- lontrel
- trichloropicolinic
- trichloropicolinic acid
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom 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
- C07D213/78—Carbon atoms having three bonds to hetero atoms, with at the most one bond to halogen, e.g. ester or nitrile radicals
- C07D213/79—Acids; Esters
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom 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
- C07D213/78—Carbon atoms having three bonds to hetero atoms, with at the most one bond to halogen, e.g. ester or nitrile radicals
- C07D213/79—Acids; Esters
- C07D213/803—Processes of preparation
Abstract
The invention discloses a method for preparing 4-amino-3,6-dichloropicolinic acid by reducing 4-amino-3,5,6-trichloropicolinic acid, which belongs to the technical field of chemical products. Under the conditions of a specific temperature, specific pressure and a specific PH value, chlorine on a pyridine ring is removed by virtue of catalytic hydrogenation to prepare 4-amino-3,6-dichloropicolinic acid. In the method, a clean and environment-friendly catalytic hydrogenation process is used for high selectively hydrogenating and reducing the 4-amino-3,5,6-trichloropicolinic acid to prepare the 4-amino-3,6-dichloropicolinic acid, and poisonous hazardous articles such as the reducing agent hydrazine and dichloromethane are not used in the production process, so that the method is moderate in reaction condition, simple in devices, convenient to operate, capable of realizing zero emission from the production of 4-amino-3,6-dichloropicolinic acid, suitable for industrialized mass production and remarkable in economical advantage and environmental protection advantage.
Description
Technical field
The invention belongs to the production technical field of Chemicals, particularly the method for amino-3, the 6-lontrel of a kind of 4-amino-3,5,6-trichloropicolinic acid reduction preparation 4-.
Background technology
4-amino-3,6-lontrel, commodity are called that Dorema ammoniacum is fixed, the acid of chlorine Fampridine, two chloroaminopyridines acid, that a kind of pyridine carboxylic acid tires out weedicide, it can enter rapidly in plant materials, is easily absorbed by stem, leaf, thus causes growth interruption and death rapidly, be mainly used in the Weeds distribution of pasture, plantation and non-agricultural cropping region, and for the weeding in Sugarbeet Fields and buckwheat field.
The synthetic method of amino-3, the 6-lontrel of 4-has chemical synthesis and electrolytic process at present.Amino-3, the 6-lontrel of chemosynthesis 4-are with 3,6-lontrel ester for raw material, complete through the step such as nitrated, reduction, hydrolysis, purification.But chemical synthesis existence uses expensive starting materials, react difficult and control, transformation efficiency is not high, and three-protection design amount greatly, waits deficiency to environment is very unfriendly, is difficult to realize industrialization.Electrolytic process be with amino-3,5, the 6-trichloropicolinic acid of 4-for raw material, completed by steps such as electrolysis, acidifying, purifications.But the method exists hydroxylation and the oxidized side reaction of amino, synthesis target compound purity is not high, only 90%, and as being used in industrialization, must carrying out aftertreatment purification, which adds production cost, three-protection design amount increases.
There is many defects in the preparation technology of amino-3, the 6-lontrel of current 4-.One is, chemical method uses mixed acid nitrification, and spent acid amount is large and difficult, very unfriendly to environment.Two are, electrolyzer existing defects in electrolytic process, in application of electrode the life-span short, must frequently replace.Three are, sepn process is seriously polluted, complex operation.Therefore, existing production technique can not meet the needs of chemical industry Sustainable development, is badly in need of advanced process for cleanly preparing and substitutes.
Summary of the invention
The present invention, in order to overcome the deficiencies in the prior art, its object is to provide a kind of 4-amino-3,5,6-trichloropicolinic acid reduction preparation 4-method of amino-3,6-lontrel.High, with low cost, easy and simple to handle, the applicable suitability for industrialized production of the method yield.
Object of the present invention is achieved through the following technical solutions: the method for amino-3, the 6-lontrel of a kind of 4-amino-3,5,6-trichloropicolinic acid reduction preparation 4-, comprises the steps:
(1) amino for 4--3,5,6-trichloropicolinic acid is dissolved in the dilute alkaline soln of 1 ~ 20 times of weight, filters, get filtrate, pour in reactor, with 4-amino-3,5,6-trichloropicolinic acid meter, in amino-3,5, the 6-trichloropicolinic acid of 4-and dilute alkaline soln, the mol ratio of alkali is 1:2 ~ 4;
(2) in reactor, add catalyzer, closed reactor, with nitrogen replacement 3 ~ 4 times, warming while stirring to 25 ~ 100 DEG C, pass into hydrogen, react, obtain reaction solution after making the pressure in reactor be raised to 0.1 ~ 1.0Mpa; The quality of described catalyzer is 1 ~ 10% of 4-amino-3,5,6-trichloropicolinic acid quality;
(3) poured out by the reaction solution of step (2), filter, get filtrate, regulate PH to 1 ~ 2 with acid, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel;
In step (1):
Described alkali is preferably the one in potassium hydroxide, sodium hydroxide, sodium carbonate or salt of wormwood.
In step (2):
Described catalyzer is preferably the one in Pd/C, Pt/C or Ri-Ni;
The temperature of described reaction is 25 ~ 100 DEG C, is preferably 30 ~ 60 DEG C;
The time of described reaction is preferably 20-30 hour.
In step (3):
Described acid is preferably the one in hydrochloric acid, dilute sulphuric acid, formic acid or acetic acid.
The present invention has following advantage and effect relative to prior art:
(1) catalytic hydrogenation process of the present invention's clean environment firendly, highly selective is by 4-amino-3,5,6-trichloropicolinic acid hydrogenating reduction prepares 4-amino-3,6-lontrel, production process is without the hypertoxic hazardous substance such as hydrazine reducing agent, methylene dichloride, and reaction conditions is gentle, meets industrial production demand.
(2) device of the present invention is simple, easy and simple to handle, cost is low, is suitable for industrialized production;
(3) the present invention is applicable to prepare the higher 4-of purity amino-3,6-lontrel, realize 4-amino-3,6-lontrel production zero release, promote the development of pyridines intermediate, agricultural chemicals and medicine, accelerate applying of green chemical technology, there is obvious economic advantages and environment-friendly advantage.
Specific embodiment
Below in conjunction with embodiment, further illustrate content of the present invention.Should be appreciated that enforcement of the present invention is not limited to the following examples, any pro forma accommodation make the present invention and/or change all will fall into scope.
In the present invention, if not refer in particular to, all parts, per-cent are weight unit, and all equipment and raw material etc. all can be buied from market or the industry is conventional.
Embodiment 1
(1) 50.8 grams of 4-amino-3,5,6-trichloropicolinic acid, 500ml water, the sodium hydroxide of 66.7 gram 30% are mixed, filter, get filtrate, pour into magnetic agitation, thermometer, ventpipe are housed 1000ml autoclave in;
(2) in reactor, add the Pd/C of 2 gram 5%, closed reactor, with nitrogen replacement 3 times, pass into hydrogen, make pressure reach 0.2Mpa, warming while stirring to 50 DEG C, continue to pass into hydrogen, carry out reaction 20 hours after making the pressure in reactor be raised to 0.3Mpa, HPLC detection reaction is complete, be cooled to room temperature, obtain reaction solution;
(3) poured out by the reaction solution of step (2), filtering recovering catalyst, gets filtrate, with 30% hcl acidifying to PH1 ~ 2, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel 38.8 grams, content 97.5%, yield 91.4%.
Embodiment 2
(1) 50.8 grams of 4-amino-3,5,6-trichloropicolinic acid, 500ml water, the sodium hydroxide of 66.7 gram 30% are mixed, filter, get filtrate, pour into magnetic agitation, thermometer, ventpipe are housed 1000ml autoclave in;
(2) in reactor, 5 grams of Ri-Ni are added, closed reactor, with nitrogen replacement 3 times, pass into hydrogen, make pressure reach 0.3Mpa, warming while stirring to 80 DEG C, continue to pass into hydrogen, carry out reaction 24 hours after making the pressure in reactor be raised to 0.4Mpa, HPLC detection reaction is complete, be cooled to room temperature, obtain reaction solution;
(3) poured out by the reaction solution of step (2), filtering recovering catalyst, gets filtrate, with 50% sulfuric acid acidation to PH1 ~ 2, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel 39.2 grams, content 97.1%, yield 91.9%.
Embodiment 3
(1) 50.8 grams of 4-amino-3,5,6-trichloropicolinic acid, 500ml water, the sodium hydroxide of 66.7 gram 30% are mixed, filter, get filtrate, pour into magnetic agitation, thermometer, ventpipe are housed 1000ml autoclave in;
(2) in reactor, add the Pd/C of 1 gram 10%, closed reactor, with nitrogen replacement 3 times, pass into hydrogen, make pressure reach 0.2Mpa, warming while stirring to 100 DEG C, continue to pass into hydrogen, carry out reaction 30 hours after making the pressure in reactor maintain 0.2Mpa, HPLC detection reaction is complete, be cooled to room temperature, obtain reaction solution;
(3) poured out by the reaction solution of step (2), filtering recovering catalyst, gets filtrate, with 30% hcl acidifying to PH1 ~ 2, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel 37.9 grams, content 98.0%, yield 89.7%.
Embodiment 4
(1) 50.8 grams of 4-amino-3,5,6-trichloropicolinic acid, 500ml water, the sodium hydroxide of 66.7 gram 30% are mixed, filter, get filtrate, pour into magnetic agitation, thermometer, ventpipe are housed 1000ml autoclave in;
(2) in reactor, add the Pt/C of 2 gram 5%, closed reactor, with nitrogen replacement 3 times, pass into hydrogen, make pressure reach 0.2Mpa, warming while stirring to 50 DEG C, continue to pass into hydrogen, carry out reaction 20 hours after making the pressure in reactor be raised to 0.3Mpa, HPLC detection reaction is complete, be cooled to room temperature, obtain reaction solution;
(3) poured out by the reaction solution of step (2), filtering recovering catalyst, gets filtrate, with 30% hcl acidifying to PH1 ~ 2, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel 39.6 grams, content 97.9%, yield 93.6%.
Embodiment 5
(1) 50.8 grams of 4-amino-3,5,6-trichloropicolinic acid, 500ml water, the potassium hydroxide of 33.0 gram 85% are mixed, filter, get filtrate, pour into magnetic agitation, thermometer, ventpipe are housed 1000ml autoclave in;
(2) in reactor, add the Pd/C of 2 gram 5%, closed reactor, with nitrogen replacement 3 times, pass into hydrogen, make pressure reach 0.2Mpa, warming while stirring to 50 DEG C, continue to pass into hydrogen, carry out reaction 20 hours after making the pressure in reactor be raised to 0.3Mpa, HPLC detection reaction is complete, be cooled to room temperature, obtain reaction solution;
(3) poured out by the reaction solution of step (2), filtering recovering catalyst, gets filtrate, with 30% hcl acidifying to PH1 ~ 2, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel 38.7 grams, content 98.5%, yield 92.1%.
Above-described embodiment is the present invention's preferably embodiment; but embodiments of the present invention are not restricted to the described embodiments; change, the modification done under other any does not deviate from spirit of the present invention and principle, substitute, combine, simplify; all should be the substitute mode of equivalence, be included within protection scope of the present invention.
Claims (7)
1. the method for amino-3, the 6-lontrel of 4-amino-3,5,6-trichloropicolinic acid reduction preparation 4-, is characterized in that, comprise the steps:
(1) amino for 4--3,5,6-trichloropicolinic acid is dissolved in the dilute alkaline soln of 1 ~ 20 times of weight, filters, get filtrate, pour in reactor, with 4-amino-3,5,6-trichloropicolinic acid meter, in amino-3,5, the 6-trichloropicolinic acid of 4-and dilute alkaline soln, the mol ratio of alkali is 1:2 ~ 4;
(2) in reactor, add catalyzer, closed reactor, with nitrogen replacement 3 ~ 4 times, warming while stirring to 25 ~ 100 DEG C, pass into hydrogen, react, obtain reaction solution after making the pressure in reactor be raised to 0.1 ~ 1.0Mpa; The quality of described catalyzer is 1 ~ 10% of 4-amino-3,5,6-trichloropicolinic acid quality;
(3) poured out by the reaction solution of step (2), filter, get filtrate, regulate PH to 1 ~ 2 with acid, centrifugal after crystallisation by cooling, get precipitation, washing, obtains 4-amino-3,6-lontrel.
2. 4-according to claim 1 amino-3, the method of amino-3, the 6-lontrel of 5,6-trichloropicolinic acid reduction preparation 4-, it is characterized in that, the alkali described in step (1) is the one in potassium hydroxide, sodium hydroxide, sodium carbonate or salt of wormwood.
3. the method for amino-3, the 6-lontrel of 4-according to claim 1 amino-3,5,6-trichloropicolinic acid reduction preparation 4-, it is characterized in that, the catalyzer described in step (2) is the one in Pd/C, Pt/C or Ri-Ni.
4. the method for amino-3, the 6-lontrel of 4-according to claim 1 amino-3,5,6-trichloropicolinic acid reduction preparation 4-, it is characterized in that, the temperature of the reaction described in step (2) is 25 ~ 100 DEG C.
5. the method for amino-3, the 6-lontrel of 4-according to claim 4 amino-3,5,6-trichloropicolinic acid reduction preparation 4-, it is characterized in that, the temperature of described reaction is 30 ~ 60 DEG C.
6. the method for amino-3, the 6-lontrel of 4-according to claim 1 amino-3,5,6-trichloropicolinic acid reduction preparation 4-, it is characterized in that, the time of the reaction described in step (2) is 20-30 hour.
7. the method for amino-3, the 6-lontrel of 4-according to claim 1 amino-3,5,6-trichloropicolinic acid reduction preparation 4-, it is characterized in that, the acid described in step (3) is the one in hydrochloric acid, dilute sulphuric acid, formic acid or acetic acid.
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| CN201510990091.2A CN105461622A (en) | 2015-12-24 | 2015-12-24 | Method for preparing 4-amino-3,6-dichloropicolinic acid by reducing 4-amino-3,5,6-trichloropicolinic acid |
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| CN201510990091.2A CN105461622A (en) | 2015-12-24 | 2015-12-24 | Method for preparing 4-amino-3,6-dichloropicolinic acid by reducing 4-amino-3,5,6-trichloropicolinic acid |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105461621A (en) * | 2015-12-24 | 2016-04-06 | 浙江埃森化学有限公司 | Method for preparing pyridine-2-formic acid by hydrogenation reduction of poly chloro pyridine-2-formic acid mixture |
| CN107778226A (en) * | 2016-08-26 | 2018-03-09 | 利尔化学股份有限公司 | A kind of purification process of the formic acid of 4 amino, 3,6 dichloropyridine 2 |
| CN108623516A (en) * | 2017-03-23 | 2018-10-09 | 利尔化学股份有限公司 | A method of improving chlorine Fampridine acid color |
| CN112321497A (en) * | 2020-12-11 | 2021-02-05 | 南京正荣医药化学有限公司 | Preparation method of 4-aminopyridine compound |
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| CN105503713A (en) * | 2015-12-24 | 2016-04-20 | 浙江埃森化学有限公司 | Method for preparing 3,6-dichloro-pyridine-2-carboxylic acid through hydrogenation reduction of 3,4,5,6-tetrachloropyridine-2-carboxylic acid |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105461621A (en) * | 2015-12-24 | 2016-04-06 | 浙江埃森化学有限公司 | Method for preparing pyridine-2-formic acid by hydrogenation reduction of poly chloro pyridine-2-formic acid mixture |
| CN107778226A (en) * | 2016-08-26 | 2018-03-09 | 利尔化学股份有限公司 | A kind of purification process of the formic acid of 4 amino, 3,6 dichloropyridine 2 |
| CN107778226B (en) * | 2016-08-26 | 2019-07-02 | 利尔化学股份有限公司 | A kind of purification process of 4- amino -3,6- dichloropyridine -2- formic acid |
| CN108623516A (en) * | 2017-03-23 | 2018-10-09 | 利尔化学股份有限公司 | A method of improving chlorine Fampridine acid color |
| CN108623516B (en) * | 2017-03-23 | 2020-08-04 | 利尔化学股份有限公司 | Method for improving color of aminopyralid |
| CN112321497A (en) * | 2020-12-11 | 2021-02-05 | 南京正荣医药化学有限公司 | Preparation method of 4-aminopyridine compound |
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Application publication date: 20160406 |