CN105461621A - Method for preparing pyridine-2-formic acid by hydrogenation reduction of poly chloro pyridine-2-formic acid mixture - Google Patents
Method for preparing pyridine-2-formic acid by hydrogenation reduction of poly chloro pyridine-2-formic acid mixture Download PDFInfo
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- CN105461621A CN105461621A CN201510988431.8A CN201510988431A CN105461621A CN 105461621 A CN105461621 A CN 105461621A CN 201510988431 A CN201510988431 A CN 201510988431A CN 105461621 A CN105461621 A CN 105461621A
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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
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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
- C07D213/803—Processes of preparation
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pyridine Compounds (AREA)
Abstract
The invention discloses a method for preparing pyridine-2-formic acid by hydrogenation reduction of a poly chloro pyridine-2-formic acid mixture, belonging to the technical field of chemical waste recycling and reusing. Under the conditions of specific temperature, pressure and PH value, and the like, through catalytic hydrogenation, chlorine on a pyridine ring is removed, and the pyridine-2-formic acid is prepared. A clean and environment-friendly catalytic hydrogenation process is used, hydrogenation reduction with high selectivity is performed on the poly chloro pyridine-2-formic acid mixture, and the pyridine-2-formic acid is prepared; highly toxic dangerous articles such as a reducing agent hydrazine and dichloromethane are not used in a production process, reaction conditions are mild, a device is simple, the operation is simple and convenient, the cost is low, zero emission in pyridine-2-formic acid production is realized, the popularization and application of a green chemical industry technology are quickened, and the method is suitable for treating the poly chloro pyridine-2-formic acid mixture with high impurity content, and has obvious economic advantages and environmental protection advantages.
Description
Technical field
The invention belongs to chemical spent material recovery and reuse technology field, particularly a kind of many chloro-pyridine-2-formic acid mixtures hydrogenating reductions prepare the method for pyridine-2-formic acid.
Background technology
3,6-lontrel is a kind of outstanding broadleaf weed herbicide, worldwide widespread use.Many chloro-pyridine-2-formic acid mixtures are the solid waste produced in the process by 3,4,5,6-4 chloro pyridine formic acid electrolysis production 3,6-lontrel.
This many chloro-pyridine-2-formic acid mixtures composition is complicated, general containing 3,6-lontrel 20 ~ 60%, also have other chloro-pyridine formic acid, and composition changes greatly, with the more difficult purification of simple physics, chemical process, generally directly as fixed-end forces, do like this and not only waste portioned product, turn increase processing cost simultaneously, therefore also need badly and a kind for the treatment of process easy is more economically provided.
Summary of the invention
The present invention, in order to overcome the deficiencies in the prior art, its object is to provide many chloro-pyridine-2-formic acid mixtures hydrogenating reductions to prepare the method for pyridine-2-formic acid.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: many chloro-pyridine-2-formic acid mixtures hydrogenating reductions prepare the method for pyridine-2-formic acid, comprise the steps:
(1) many chloro-pyridine-2-formic acid waste material mixtures are dissolved in the dilute alkaline soln of 1 ~ 20 times of weight, filter, get filtrate, pour in reactor, with 3,6-lontrel meter, in 3,6-lontrel and dilute alkaline soln, the mol ratio of alkali is 1:3 ~ 6;
(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 many chloro-pyridine-2-formic acid waste material mixture quality;
(3) reaction solution of step (2) is poured out, filter, get filtrate, regulate PH to 1 ~ 2 with acid, through macroporous resin adsorption, collect effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol and dissolve, filter, by filtrate reduced in volume, be precipitated as pyridine-2-formic acid.
In step (1):
Described many chloro-pyridine-2-formic acid waste material mixtures be containing weight percent be 20 ~ 60% 3,6-lontrel; Preferably comprise the part of following weight percent: a chloropyridine formic acid 0 ~ 20%, lontrel 20 ~ 60%, trichloropicolinic acid 0 ~ 30%, 4 chloro pyridine formic acid 0 ~ 20%.
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 20-40 hour.
In step (3):
Described acid is preferably the one in hydrochloric acid, dilute sulphuric acid, formic acid or acetic acid;
Described macroporous resin is preferably acid macroporous resin.
The present invention has following advantage and effect relative to prior art:
(1) catalytic hydrogenation process of the present invention's clean environment firendly, chloro-pyridine acid hydrogenating reduction is prepared pyridine-2-formic acid by highly selective, 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 pyridine-2-formic acid of purity, realize pyridine-2-formic acid production zero release, accelerate applying of green chemical technology, be applicable to the process of many chloro-pyridine-2-formic acid mixtures of high impurity content (foreign matter content 40 ~ 80%), 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) formic acid of chloro-pyridine-2-more than 50 grams waste material mixture, 400ml water, the sodium hydroxide of 139.6 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 0.4Mpa, 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 0.5Mpa, 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, through acid macroporous resin adsorption, collects effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol 200ml and dissolve, filter, by filtrate reduced in volume, crystallisation by cooling, obtains 27.5 grams, pyridine-2-formic acid, content 98.2%, yield 73.1%.
Embodiment 2
(1) formic acid of chloro-pyridine-2-more than 50 grams waste material mixture, 400ml water, the sodium hydroxide of 140 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 0.4Mpa, 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 0.5Mpa, 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, through acid macroporous resin adsorption, collects effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol 200ml and dissolve, filter, by filtrate reduced in volume, crystallisation by cooling, obtains 26.3 grams, pyridine-2-formic acid, content 98.1%, yield 69.9%.
Embodiment 3
(1) formic acid of chloro-pyridine-2-more than 50 grams waste material mixture, 400ml water, the sodium hydroxide of 139.6 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, through acid macroporous resin adsorption, collects effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol 200ml and dissolve, filter, by filtrate reduced in volume, crystallisation by cooling, obtains 25.8 grams, pyridine-2-formic acid, content 98.0%, yield 68.5%.
Embodiment 4
(1) formic acid of chloro-pyridine-2-more than 50 grams waste material mixture, 400ml water, the sodium hydroxide of 139.8 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 0.4Mpa, 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 0.5Mpa, 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, through acid macroporous resin adsorption, collects effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol 200ml and dissolve, filter, by filtrate reduced in volume, crystallisation by cooling, obtains 26.9 grams, pyridine-2-formic acid, content 98.9%, yield 72.0%.
Embodiment 5
(1) formic acid of chloro-pyridine-2-more than 50 grams waste material mixture, 500ml water, the potassium hydroxide of 65.5 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 0.4Mpa, 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 0.5Mpa, 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, through acid macroporous resin adsorption, collects effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol 200ml and dissolve, filter, by filtrate reduced in volume, crystallisation by cooling, obtains 27.7 grams, pyridine-2-formic acid, content 99.1%, yield 74.3%.
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 (10)
1.-the 2-of chloro-pyridine more than formic acid mixtures hydrogenating reduction prepares a method for pyridine-2-formic acid, it is characterized in that, comprises the steps:
(1) many chloro-pyridine-2-formic acid waste material mixtures are dissolved in the dilute alkaline soln of 1 ~ 20 times of weight, filter, get filtrate, pour in reactor, with 3,6-lontrel meter, in 3,6-lontrel and dilute alkaline soln, the mol ratio of alkali is 1:3 ~ 6;
(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 many chloro-pyridine-2-formic acid waste material mixture quality;
(3) reaction solution of step (2) is poured out, filter, get filtrate, regulate PH to 1 ~ 2 with acid, through macroporous resin adsorption, collect effluent liquid; By effluent liquid decompression dehydration to dry, add anhydrous methanol and dissolve, filter, by filtrate reduced in volume, be precipitated as pyridine-2-formic acid.
2. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, it is characterized in that, many chloro-pyridine-2-formic acid waste material mixtures described in step (1) be containing weight percent be 20 ~ 60% 3,6-lontrel.
3. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, it is characterized in that, many chloro-pyridine-2-formic acid waste material mixtures described in step (1) comprise the part of following weight percent: a chloropyridine formic acid 0 ~ 20%, lontrel 20 ~ 60%, trichloropicolinic acid 0 ~ 30%, 4 chloro pyridine formic acid 0 ~ 20%.
4. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, and 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.
5. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, and it is characterized in that, the catalyzer described in step (2) is the one in Pd/C, Pt/C or Ri-Ni.
6. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, and it is characterized in that, the temperature of the reaction described in step (2) is 25 ~ 100 DEG C.
7. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 6 prepare the method for pyridine-2-formic acid, and it is characterized in that, the temperature of described reaction is 30 ~ 60 DEG C.
8. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, and it is characterized in that, the time of the reaction described in step (2) is 10-50 hour.
9. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, and 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.
10. many chloro-pyridine-2-formic acid mixtures hydrogenating reductions according to claim 1 prepare the method for pyridine-2-formic acid, and it is characterized in that, the macroporous resin described in step (3) is acid macroporous resin.
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Application publication date: 20160406 |