CN105218432A - A kind of 4, the method for purification of 4 '-dipyridyl - Google Patents
A kind of 4, the method for purification of 4 '-dipyridyl Download PDFInfo
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- CN105218432A CN105218432A CN201510587076.3A CN201510587076A CN105218432A CN 105218432 A CN105218432 A CN 105218432A CN 201510587076 A CN201510587076 A CN 201510587076A CN 105218432 A CN105218432 A CN 105218432A
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- dipyridyl
- dipyridyls
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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
- C07D213/06—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 containing only hydrogen and carbon atoms in addition to the ring nitrogen atom
- C07D213/22—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 containing only hydrogen and carbon atoms in addition to the ring nitrogen atom containing two or more pyridine rings directly linked together, e.g. bipyridyl
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Abstract
The invention discloses a kind of 4, the method of purification of 4 ˊ-dipyridyl, by industry 4,4 ˊ-dipyridyl adds heating for dissolving in ethanol, then add after gac stirs for some time and filter, add diatomite again and fully stir rear filtration, then filtrate is concentrated into finite concentration, add deionized water and promote crystallization, filtration, obtain 4,4 ˊ good-dipyridyl of purifying after drying.Method of purification provided by the present invention, easy to operate, constant product quality, be applicable to suitability for industrialized production, can make 4, the content of 4 ˊ-dipyridyl is increased to and is greater than 99.5wt%, and yield is greater than 90%, and indices all meets chemical reagent standard.
Description
Technical field
The invention belongs to chemical purification field, particularly relate to a kind of method of purification of chemical reagent 4,4'-dipyridyl.
Background technology
4,4'-dipyridyl is more and more extensive as the research and apply of agricultural chemicals or medicine intermediate, main because 4,4'-dipyridyls are organic bridge ligands of wire rigidity of a kind of excellent property.Imperial Chemical Industries group of Britain is pioneering to be developed low temperature sodium technique and carries out scale operation 4,4'-dipyridyl.The enterprise of current domestic scale operation 4,4'-dipyridyl rarely has report, and 4, the 4'-dipyridyl chemical reagent for fundamental research are external import mostly, so cause the on the high side of 4,4'-dipyridyl reagent.And the industry 4 of domestic procurement, the indices of 4'-dipyridyl is difficult to again the requirement meeting chemical reagent, general needs are to industry 4,4'-dipyridyl carries out purifying, but in purge process, mostly use benzene, chloroparaffin or ether equal solvent, not only the health of operator is worked the mischief, but also realistic threat is produced to surrounding enviroment, also add enterprise cost.
Summary of the invention
In order to overcome the deficiencies in the prior art, the object of the present invention is to provide a kind of purification process easy to operate, and avoid using noxious solvent, yield is higher, and products obtained therefrom purity is high, reaches the method for purification of one 4, the 4'-dipyridyl of the needs meeting Domestic Scientific Research.
For achieving the above object, the present invention is achieved by the following technical solutions.
A kind of method of purification of 4,4'-dipyridyl, is characterized in that, comprise the steps:
(1) industry 4,4'-dipyridyl is added heating for dissolving in ethanol;
(2) to be dissolved completely after add sorbent material, filter after stirring;
(3) filtrate is concentrated, just concentrated by stopping when becoming muddy clearly to filtrate;
(4) in concentrated solution, deionized water is added, crystallisation by cooling;
(5) dry after crystallization being removed mother liquor, obtain 4,4'-dipyridyls of purifying.
In described step (1), the mass ratio of 4,4'-dipyridyls and ethanol is 1:0.7 ~ 10 further, and the mass ratio of preferred 4,4'-dipyridyls and ethanol is 1:1 ~ 3.4,4'-dipyridyl is more crucial for whole purge process with the proportioning of ethanol, if ethanol consumption is few, dissolves 4,4'-dipyridyl can be more difficult, need to be heated to higher temperature, more high decomposition or the carbonization more easily causing 4,4'-dipyridyl of temperature, and because concentration is high when filtering, filtration resistance is large, filters relative difficulty filter quality poor, but can save time and energy consumption when subsequent concentration; If ethanol consumption is many, dissolve 4,4'-dipyridyl can be relatively easy, do not need higher temperature just can all dissolve, and due at the bottom of concentration when filtering, filtration resistance reduce greatly, filter relatively easy filter quality high, but time and energy consumption can be increased when subsequent concentration, therefore through repeatedly testing the optimum proportioning obtaining 4,4'-dipyridyl and ethanol.
Weight percent content >=90% of the middle ethanol of described step (1) further.The ethanol distilled out in concentration process can be used as solvent, reduce the consumption of raw material.
In described step (2), sorbent material is gac and diatomite further; In step (2) to be dissolved completely after first add after gac stirs 5 ~ 50min and filter, then add after diatomite fully stirs 5 ~ 50min and filter; The weight ratio of gac and 4,4'-dipyridyl is 0.5 ~ 5%:1, and the weight ratio of diatomite and 4,4'-dipyridyl is 0.5 ~ 5%:1.Gac specific surface area is large, and physical adsorption ability is strong, can adsorb major part industry 4, impurity in 4'-dipyridyl, but also have certain decoloring ability, but active carbon powder easily wears worry, makes the micro-muddiness of filtrate, diatomite is added again after charcoal absorption, because diatomite has abundant microvoid structure, polar adsorption ability is strong, can polar molecule in adsorbent solution, the gac that previous step wears worry can also be fallen by aided filter, make filtrate clear.
Concentrated employing normal pressure or concentrating under reduced pressure in described step (3) further, thickening temperature controls at 35 ~ 90 DEG C.
First add in concentrated solution in described step (4) further and account for concentrated solution volume 1/5, temperature higher than the deionized water of concentrated solution 10 DEG C, when system temperature is down to room temperature, at the uniform velocity add again account for former concentrated solution volume 4/5, temperature is the deionized water of room temperature, adds the time controling of deionized water at 8 ~ 12h; Or the concentrated solution of step (4) is heated to clarification, then leave standstill and be cooled to room temperature, at the uniform velocity adding, temperature equal with concentrated solution volume is the deionized water of room temperature, adds the time controling of deionized water at 8 ~ 12h.4,4'-dipyridyl solubleness is in ethanol comparatively large, if only crystallization in ethanol, has 4,4'-a large amount of dipyridyls and stays in ethanol, reduce a yield, add cost burden; Deionized water is added in concentrated solution, because ethanol is miscible and 4 in water, 4'-dipyridyl is slightly soluble in deionized water, 4, the 4'-dipyridyls being dissolved in mother liquor can be separated out in a large number, improve a yield, but add disposable for deionized water or add excessive velocities, it is unformed powder that 4,4'-dipyridyl can be made to separate out rapidly gained crystal, may remove in follow-up de-mother liquor process clean, carry impurity secretly, in drying course, also can extend time of drying.First add in concentrated solution and account for concentrated solution volume 1/5, temperature is higher than the deionized water of concentrated solution 10 DEG C, can by concentrated solution temperature increase, by firm crystallization 4, 4'-dipyridyl molecule dissolves again, solution to be concentrated slow cooling, 4, 4'-dipyridyl crystal is progressively formed, there is certain crystalline form, during to room temperature, at the uniform velocity add again and account for former concentrated solution volume 4/5, temperature is the deionized water of room temperature, add the time controling of deionized water at 8 ~ 12h, slow reduction by 4, the solubleness of 4'-dipyridyl in mother liquor, continued growth on the crystal formerly formed, obtain crystalline form consistent, evengranular crystal, also concentrated solution can be reheated, by firm crystallization 4,4'-dipyridyl molecule dissolves again, solution to be concentrated slow cooling, 4,4'-dipyridyl crystal is progressively formed, there is certain crystalline form, during to room temperature, at the uniform velocity adding, temperature equal with concentrated solution volume is the deionized water of room temperature, adds the time controling of deionized water at 8 ~ 12h.
Use washed with de-ionized water crystallization after crystallization removes mother liquor in described step (5) further, then at 50 ~ 100 DEG C, time of drying is at 3 ~ 10h.Because ethanol is category-A flammable and combustible liquids, the material dried containing ethanol must adopt explosion-proof baking oven.The crystalline form generated due to step (4) is consistent, uniform particles, and specific surface area is little, uses deionized water rinsing crystallization, is easy to the alcohol flushing of plane of crystal clean, just can adopt a conventional oven when drying, and reduces the input of fixed capital.
Beneficial effect: compared with prior art, the invention has the advantages that:
1) involved in the present invention etoh solvent and deionized water are all nontoxic or low toxicity and common agents cheap and easy to get, can effective guarantee personnel health and management and control environmental risk, and can reuse;
2) in the present invention, the purity of 4,4'-dipyridyls of purifying is greater than 99.5%, and yield is greater than 90%, and fusing point, dissolve with ethanol test index all meet chemical reagent standard;
3) in the present invention, 4,4'-dipyridyl crystalline forms of purifying are consistent, and crystal is full, and product are mutually good;
4) 4, the 4'-dipyridyl reagent qualities that the present invention obtains are stablized, easy and simple to handle, are applicable to suitability for industrialized production.
Embodiment
Below in conjunction with example, the present invention is described in further detail.
Embodiment 1
Dehydrated alcohol 200g is added in the reaction unit that agitator and temperature regulator are housed, industry 4,4'-dipyridyl 100g, heating for dissolving under constantly stirring, then add 2.0g gac and stir 15min at 50 DEG C, after filtered while hot, then refilter add 2.0g diatomite stirring 15min in filtrate after.Gained filtrate is carried out concentrating under reduced pressure, temperature controls at 35 ~ 45 DEG C, when most of solvent is evaporated to filtrate just by stopping when becoming muddy clearly concentrating, reheat concentrated solution to clarification, leave standstill again and be cooled to room temperature, 4,4'-dipyridyl crystal is progressively formed, have certain crystalline form, more at the uniform velocity to add, temperature equal with concentrated solution volume be the deionized water of room temperature, add the time controling of deionized water at 8h, then centrifugally mother liquor is removed, and wash crystalline substance with deionized water, gained crystal can be obtained 4,4'-good dipyridyls of 90g purifying in 70 DEG C of baking ovens after dry 6h.
Detected result shows, the indices of 4, the 4'-dipyridyls that purifying is good all meets the standard of chemical reagent, and the concrete data that detect are in table 1:
Table 1
| Sequence number | Test item | Unit | Standard gauge definite value | Measured value |
| 1 | Content (C 10H 8N 2) | W/％ | ≥98.0 | 99.7 |
| 2 | Dissolve with ethanol is tested | Qualified | Qualified | |
| 3 | Melting range | ℃ | 109.0～113.0(3) | 109.3-113.0 |
| 4 | Ignition residue (in vitriol) | W/％ | ≤0.1 | 0.09 |
Embodiment 2
The ethanol 2000g that weight percent content is 90% is added in the reaction unit that agitator and temperature regulator are housed, industry 4,4'-dipyridyl 200g, heating for dissolving under constantly stirring, then add 10.0g gac and stir 5min at 50 DEG C, after filtered while hot, then refilter add 10.0g diatomite stirring 5min in filtrate after.Gained filtrate is carried out concentrating under reduced pressure, temperature controls at 35 ~ 45 DEG C, when most of solvent is evaporated to filtrate just by stopping when becoming muddy clearly concentrating, first add in concentrated solution and account for concentrated solution volume 1/5, temperature is higher than the deionized water of concentrated solution 10 DEG C, when system temperature is down to room temperature, at the uniform velocity add again and account for former concentrated solution volume 4/5, temperature is the deionized water of room temperature, add the time controling of deionized water at 10h, then centrifugally mother liquor is removed, and wash crystalline substance with deionized water, gained crystal can be obtained after dry 10h in 50 DEG C of baking ovens 185g purifying good 4, 4'-dipyridyl.
Detected result shows, the indices of 4, the 4'-dipyridyls that purifying is good all meets the standard of chemical reagent, and the concrete data that detect are in table 2:
Table 2
| Sequence number | Test item | Unit | Standard gauge definite value | Measured value |
| 1 | Content (C 10H 8N 2) | W/％ | ≥98.0 | 99.8 |
| 2 | Dissolve with ethanol is tested | Qualified | Qualified | |
| 3 | Melting range | ℃ | 109.0～113.0(3) | 111.9～112.9 |
| 4 | Ignition residue (in vitriol) | W/％ | ≤0.1 | 0.05 |
Embodiment 3
Dehydrated alcohol 140g is added in the reaction unit that agitator and temperature regulator are housed, industry 4,4'-dipyridyl 200g, heating for dissolving under constantly stirring, then add 1.0g gac and stir 50min at 50 DEG C, after filtered while hot, then refilter add 1.0g diatomite stirring 50min in filtrate after.Gained filtrate is carried out normal pressure concentrate, temperature controls at 75 ~ 90 DEG C, when most of solvent is evaporated to filtrate just by stopping when becoming muddy clearly concentrating, first add in concentrated solution and account for concentrated solution volume 1/5, temperature is higher than the deionized water of concentrated solution 10 DEG C, when system temperature is down to room temperature, at the uniform velocity add again and account for former concentrated solution volume 4/5, temperature is the deionized water of room temperature, add the time controling of deionized water at 12h, then centrifugally mother liquor is removed, and wash crystalline substance with deionized water, gained crystal can be obtained after dry 5h in 80 DEG C of baking ovens 182g purifying good 4, 4'-dipyridyl.
Detected result shows, the indices of 4, the 4'-dipyridyls that purifying is good all meets the standard of chemical reagent, and the concrete data that detect are in table 3:
Table 3
| Sequence number | Test item | Unit | Standard gauge definite value | Measured value |
| 1 | Content (C 10H 8N 2) | W/％ | ≥98.0 | 99.6 |
| 2 | Dissolve with ethanol is tested | Qualified | Qualified | |
| 3 | Melting range | ℃ | 109.0～113.0(3) | 109.1-112.8 |
| 4 | Ignition residue (in vitriol) | W/％ | ≤0.1 | 0.08 |
Embodiment 4
The ethanol 100g that weight percent content is 95% is added in the reaction unit that agitator and temperature regulator are housed, industry 4,4'-dipyridyl 100g, heating for dissolving under constantly stirring, then add 2.5g gac and stir 25min at 50 DEG C, after filtered while hot, then refilter add 2.5g diatomite stirring 25min in filtrate after.Gained filtrate is carried out concentrating under reduced pressure, temperature controls at 35 ~ 45 DEG C, when most of solvent is evaporated to filtrate just by stopping when becoming muddy clearly concentrating, first add in concentrated solution and account for concentrated solution volume 1/5, temperature higher than the deionized water of concentrated solution 10 DEG C, when system temperature is down to room temperature, at the uniform velocity add again account for former concentrated solution volume 4/5, temperature is the deionized water of room temperature, add the time controling of deionized water at 10h, then centrifugally mother liquor is removed, and wash crystalline substance with deionized water, gained crystal can be obtained 4,4'-good dipyridyls of 92g purifying in 90 DEG C of baking ovens after dry 4h.
Detected result shows, the indices of 4, the 4'-dipyridyls that purifying is good all meets the standard of chemical reagent, and the concrete data that detect are in table 4:
Table 4
| Sequence number | Test item | Unit | Standard gauge definite value | Measured value |
| 1 | Content (C 10H 8N 2) | W/％ | ≥98.0 | 99.8 |
| 2 | Dissolve with ethanol is tested | Qualified | Qualified | |
| 3 | Melting range | ℃ | 109.0～113.0(3) | 110.7～112.3 |
| 4 | Ignition residue (in vitriol) | W/％ | ≤0.1 | 0.06 |
Embodiment 5
The ethanol 300g that weight percent content is 95% is added in the reaction unit that agitator and temperature regulator are housed, industry 4,4'-dipyridyl 100g, heating for dissolving under constantly stirring, then add 4g gac and stir 10min at 50 DEG C, after filtered while hot, then refilter add 4g diatomite stirring 10min in filtrate after.Gained filtrate is carried out concentrating under reduced pressure, temperature controls at 35 ~ 45 DEG C, when most of solvent is evaporated to filtrate just by stopping when becoming muddy clearly concentrating, reheat concentrated solution to clarification, leave standstill again and be cooled to room temperature, 4,4'-dipyridyl crystal is progressively formed, have certain crystalline form, more at the uniform velocity to add, temperature equal with concentrated solution volume be the deionized water of room temperature, add the time controling of deionized water at 12h, then centrifugally mother liquor is removed, and wash crystalline substance with deionized water, gained crystal can be obtained 4,4'-good dipyridyls of 93g purifying in 100 DEG C of baking ovens after dry 3h.
Detected result shows, the indices of 4, the 4'-dipyridyls that purifying is good all meets the standard of chemical reagent, and the concrete data that detect are in table 5:
Table 5
| Sequence number | Test item | Unit | Standard gauge definite value | Measured value |
| 1 | Content (C 10H 8N 2) | W/％ | ≥98.0 | 99.9 |
| 2 | Dissolve with ethanol is tested | Qualified | Qualified | |
| 3 | Melting range | ℃ | 109.0～113.0(3) | 110.4～111.5 |
| 4 | Ignition residue (in vitriol) | W/％ | ≤0.1 | 0.05 |
The present invention is illustrated according to above-described embodiment, should be appreciated that above-described embodiment does not limit the present invention in any form, and all employings are equal to replacement or the technical scheme that obtains of equivalent transformation mode, all drop within protection scope of the present invention.
Claims (10)
1. the method for purification of a dipyridyl, is characterized in that, comprises the steps:
(1) industry 4,4'-dipyridyl is added heating for dissolving in ethanol;
(2) to be dissolved completely after add sorbent material, filter after stirring;
(3) filtrate is concentrated, just concentrated by stopping when becoming muddy clearly to filtrate;
(4) in concentrated solution, deionized water is added, crystallisation by cooling;
(5) dry after crystallization being removed mother liquor, obtain 4,4'-dipyridyls of purifying.
2. the method for purification of a kind of 4,4'-dipyridyls according to claim 1, is characterized in that, in described step (1), the mass ratio of 4,4'-dipyridyls and ethanol is 1:0.7 ~ 10.
3. the method for purification of a kind of 4,4'-dipyridyls according to claim 2, is characterized in that, in described step (1), the mass ratio of 4,4'-dipyridyls and ethanol is 1:1 ~ 3.
4. the method for purification of a kind of 4,4'-dipyridyls according to claim 1, is characterized in that, weight percent content >=90% of ethanol in described step (1).
5. the method for purification of a kind of 4,4'-dipyridyls according to claim 1, is characterized in that, in described step (2), sorbent material is gac and diatomite.
6. the method for purification of a kind of 4,4'-dipyridyls according to claim 5, is characterized in that, in described step (2) to be dissolved completely after first add after gac stirs 5 ~ 50min and filter, then add after diatomite fully stirs 5 ~ 50min and filter.
7. the method for purification of a kind of 4,4'-dipyridyls according to claim 5, is characterized in that, the weight ratio of described gac and 4,4'-dipyridyl is 0.5 ~ 5%:1, and the weight ratio of described diatomite and 4,4'-dipyridyl is 0.5 ~ 5%:1.
8. the method for purification of a kind of 4,4'-dipyridyls according to claim 1, is characterized in that, concentrated employing normal pressure or concentrating under reduced pressure in described step (3), thickening temperature controls at 35 ~ 90 DEG C.
9. according to claim 1 a kind of 4, the method of purification of 4'-dipyridyl, it is characterized in that, first add in concentrated solution in described step (4) and account for concentrated solution volume 1/5, temperature higher than the deionized water of concentrated solution 10 DEG C, when system temperature is down to room temperature, at the uniform velocity add again account for former concentrated solution volume 4/5, temperature is the deionized water of room temperature, adds the time controling of deionized water at 8 ~ 12h; Or the concentrated solution of step (4) is heated to clarification, then leave standstill and be cooled to room temperature, at the uniform velocity adding, temperature equal with concentrated solution volume is the deionized water of room temperature, adds the time controling of deionized water at 8 ~ 12h.
10. the method for purification of a kind of 4,4'-dipyridyls according to claim 1, is characterized in that, use washed with de-ionized water crystallization after crystallization removes mother liquor in described step (5), then at 50 ~ 100 DEG C, time of drying is at 3 ~ 10h.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB996570A (en) * | 1962-02-27 | 1965-06-30 | Ici Ltd | Purification of bipyridyls |
| GB1043356A (en) * | 1963-02-13 | 1966-09-21 | Ici Ltd | Purification of bipyridyls |
-
2015
- 2015-09-15 CN CN201510587076.3A patent/CN105218432A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB996570A (en) * | 1962-02-27 | 1965-06-30 | Ici Ltd | Purification of bipyridyls |
| GB1043356A (en) * | 1963-02-13 | 1966-09-21 | Ici Ltd | Purification of bipyridyls |
Non-Patent Citations (2)
| Title |
|---|
| HART, E. P.: "2,4"-Dipiperidyl: Its structure and derivatives", 《JOURNAL OF THE CHEMICAL SOCIETY》 * |
| 孟繁智: "《新编精细化工应用配方10000例与生产工艺实用手册(下卷)》", 29 February 2004 * |
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