CN104130183A - Synthetic method for 3-bromopyridine - Google Patents
Synthetic method for 3-bromopyridine Download PDFInfo
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- CN104130183A CN104130183A CN201410356568.7A CN201410356568A CN104130183A CN 104130183 A CN104130183 A CN 104130183A CN 201410356568 A CN201410356568 A CN 201410356568A CN 104130183 A CN104130183 A CN 104130183A
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- 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
- C07D213/61—Halogen atoms or nitro radicals
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Abstract
The invention provides a synthetic method for 3-bromopyridine. The synthetic method comprises a first step of mixing pyridine and a hydrobromic acid solution and carrying out a reaction under the action of hydrogen peroxide so as to produce a crude product and a second step of carrying out purification so as to obtain 3-bromopyridine. The invention further provides 3-bromopyridine prepared by using the synthetic method. According to the method, cheap and easily available reagents are used, corresponding conversion is completed only through the one-step reaction, high temperature and high pressure are not needed, a synthetic route is simple, complex post-treatment is not needed, production cost is reduced, and the method has good industrial application prospects.
Description
Technical field
The synthetic method that the present invention relates to a kind of 3-bromopyridine, belongs to technical field of organic synthesis.
Background technology
At medicine and pesticide field, 3-bromopyridine has a wide range of applications, and is the important intermediate of thymoleptic hydrochloric acid zimeldine, is also the important intermediate of neurological drug preclamol; In addition, 3-bromopyridine also has application in field of photovoltaic materials.Therefore, the demand of 3-bromopyridine is huge.
In industrial related industries, cheapness, efficient, easy and simple to handle, the synthesis technique that is suitable for suitability for industrialized production, will have very large pushing effect for the application of 3-bromopyridine.
As everyone knows, due to the short of electricity of pyridine ring, the parent of pyridine and halogen electricity halogenating reaction is difficult to carry out.In addition because pyridine will change into immediately electrophilic reagent (or from the proton of medium, or Lewis acid) in containing electrophilic medium, and form pyridylium with nitrogen-atoms.Obviously, with the pyridylium of positive charge than uncharged heterocycle carbon atom by the easy degree of electrophilic reagent attack low the order of magnitude also; This further causes the degree of difficulty of pyridine electrophilic substitution, so will carry out the halogenating reaction of pyridine, conventionally needs high temperature and/or strong acid condition.Because bromine boiling point is lower, so reaction also needs pressure exerting device.Ciamician and Silber (Ueber Monobrompyridin, Chem.Ber, 1885:722) by by pyridine hydrochloride and bromine in tube sealing system, being heated to 210-230 ℃ reacts, obtain 3-bromopyridine and with a large amount of 3,5-dihalo-pyridine and tarring compound, chemical equation is as follows:
Extend the reaction times to 24 hour, single bromo and two pyridine bromide sums are less than 21% of all substances total amount in reaction system.Blau (Notiz zur Darstellung von Mono-und Di-Brompyridin, Monatsh, 1889:372) reported a method that improves transformation efficiency, it is in tube sealing system, by the mixture of bromine and carbonic acid gas is continued to pass in the pyridine hydrochloride of melting, make the overall yield of single bromo and two bromos bring up to 42%.
Fred Lowell Taylor (US2480091) etc. finds that when carrying out pyridine bromination 3-bromopyridine hydrochloride boiling point is low more than pyridine hydrochloride, and 3-bromopyridine hydrochloride can distill from reaction system.According to this characteristic, author carries out bromination by carry out the method for limit coronite distillation in a custom-designed reactor, finally 3-bromopyridine yield is brought up to 70% of theoretical amount.But this reaction needed is carried out in the pressure exerting device of a particular design, and still needs high temperature (170 ℃), high pressure.
For reducing temperature of reaction, (Bromination of pyridine in the presence of some lewis acids such as Lokhov, Chemistry of Heterocyclic Compounds, 17:923-926) trial use Lewis acid catalysis pyridine reacts with bromine, makes temperature of reaction be down to 100 ℃.Research finds that result is best under InCl3 catalyst action, although total conversion rate reaches more than 60%.But under this condition, still follow a large amount of 3, the generation of 5-dibromo pyridine (43.1%, target product 3-bromopyridine only has 21.4%).
The salt that pyridine at room temperature reacts generated with mercuric acetate at 180 ℃, heat the further bromination of the rearrangeable 3-of one-tenth acetyl oxygen mercury pyridine be converted into 3-bromopyridine (J.A. joule K. Mil Si work. sincere by industry, tall and big refined grade is translated, heterocyclic chemistry (the 4th edition) [M]. Science Press: 66), its chemical equation is as follows:
There is the attack of relatively weak electrophilic reagent to carbon in this process, described the same with Mercury bisulfate catalysis sulfonation reaction, may relate to the attack to free pyridine in balance.This reaction conditions still needs high temperature, and need to use poisonous mercurous material.
Except the direct bromination of above-mentioned pyridine, prepare the method for 3-bromopyridine, also have the synthetic 3-bromopyridine in the following two kinds of paths of bibliographical information.
1) be shown below, by 3-aminopyridine, or aminopyridine (salt) diazotization, carry out again sandmeyer reaction and obtain product (Synthese de xanthones et thioxanthones a deuxnoyaux heteroatomiques.J.Chem.Res, Miniprint, 1982,3:912 – 942).These technique starting material are more expensive, are not suitable for industrialization.
2) be shown below, by nicotinic acid, directly degrade and prepare 3-bromopyridine (Decarboxylative ipso halogenation of mercury (II) pyridinecarboxylates.Facile formation of3-iodo-and3-bromopyridines.J.Org.Chem, 1983,48 (19): 3297 – 3301).This process recovery ratio only has 27%, and starting material are also more expensive, and will use poisonous compound containing mercury or more expensive argentum reagent, is not suitable for industrialization.
Summary of the invention
In view of the defect that above-mentioned prior art exists, the object of the invention is to propose a kind of synthetic method of 3-bromopyridine, can improve the productive rate of 3-bromopyridine, do not need High Temperature High Pressure, reduce the requirement to reaction conditions, be applicable to suitability for industrialized production.
Object of the present invention is achieved by the following technical programs:
A synthetic method for 3-bromopyridine, it comprise pyridine is mixed with hydrobromic acid solution after under hydrogen peroxide effect reaction generate thick product, by purification, obtain the step of 3-bromopyridine.
Above-mentioned purification comprises alkali neutralization, extraction and concentrated step.
In the synthetic method of above-mentioned 3-bromopyridine, preferred, it comprises the steps:
After pyridine is mixed with water, then mix with HBr solution, under the condition of 0-40 ℃, be stirred to molten clearly, obtain bromination reaction liquid, wherein, in weight part, pyridine: water: HBr solution=1: 1.67: (2.5-6);
Bromination reaction liquid is mixed at 70 ℃-120 ℃ with hydrogen peroxide solution, then, at 80 ℃-120 ℃ reaction 1h-48h, obtain thick product, wherein, in weight part, pyridine: hydrogen peroxide solution=1: (1.5-4);
With the aqueous sodium hydroxide solution of 3N, adjust pH to alkalescence thick product, then use organic solvent extraction, be extracted liquid;
Underpressure distillation after extraction liquid is concentrated, obtains 3-bromopyridine.
In the synthetic method of above-mentioned 3-bromopyridine, its building-up reactions formula is as follows:
In the synthetic method of above-mentioned 3-bromopyridine, describedly moltenly refer to that clearly reactant dissolves completely.
In the synthetic method of above-mentioned 3-bromopyridine, preferred, in weight part, pyridine: hydrogen peroxide solution=1: (1.5-3).
In the synthetic method of above-mentioned 3-bromopyridine, preferred, the concentration of described HBr solution is 35%-48%; Preferred, the concentration of described HBr solution is 40%.
In the synthetic method of above-mentioned 3-bromopyridine, preferred, the concentration of described hydrogen peroxide solution is 25%-35%; Preferred, the concentration of described hydrogen peroxide solution is 30%.
In the synthetic method of above-mentioned 3-bromopyridine, organic solvent can be the immiscible solvent of any and water, preferred, and described organic solvent comprises one or more the combination in ethyl acetate, methylene dichloride, toluene and methyl tertiary butyl ether etc.
The 3-bromopyridine that the present invention also provides a kind of synthetic method of above-mentioned 3-bromopyridine to obtain.
Outstanding effect of the present invention is:
Compare the high temperature (170 ℃) that original technique generally needs, high pressure, the present invention does not need High Temperature High Pressure, reduces the requirement to reaction conditions and equipment;
Compare original process recovery ratio on the low side, too many with the two replacement of Lewis acid catalyzed reaction impurity, with 3-aminopyridine or nicotinic acid, be that raw material is prepared 3-bromopyridine, the cost of raw material own is too high, step is oversize and yield is not high, the inventive method, with some cheapnesss, the reagent that is easy to get, only needs 1 step react corresponding conversion, and does not need High Temperature High Pressure, synthetic route is easy and simple to handle simultaneously, there is no complicated last handling process, reduced production cost, this also makes the inventive method have good prospects for commercial application.
Embodiment
Below by specific embodiment, method of the present invention is described, so that technical solution of the present invention is easier to understand, grasp, but the present invention is not limited thereto.Experimental technique described in following embodiment, if no special instructions, is ordinary method; Described reagent and material, if no special instructions, all can obtain from commercial channels.
Embodiment 1
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (160g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 70 ℃, bromination reaction liquid slowly drips 30%H
2o
280mL, drips 70-80 ℃ of process control temp (the slow heat release of dropping process), dropwises 80 ℃ of stirring reactions of rear temperature control 24 hours, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add ethyl acetate (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 31g, and GC purity is 85.1%.
Embodiment 2
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (160g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 85 ℃, bromination reaction liquid slowly drips 30%H
2o
280mL, drips 85-95 ℃ of process control temp (the slow heat release of dropping process), dropwises 95 ℃ of stirring reactions of rear temperature control 24 hours, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add ethyl acetate (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 46g, and GC purity is 89.4%.
Embodiment 3
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (160g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 100 ℃, bromination reaction liquid slowly drips 30%H
2o
280mL, drips 100-110 ℃ of process control temp (the slow heat release of dropping process), dropwises 110 ℃ of stirring reactions of rear temperature control 24 hours, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add methylene dichloride (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 55g, and GC purity is 97.5%.
Embodiment 4
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (160g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 110 ℃, bromination reaction liquid slowly drips 30%H
2o
280mL, drips 110-120 ℃ of process control temp (the slow heat release of dropping process), dropwises 120 ℃ of stirring reactions of rear temperature control 24 hours, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add methylene dichloride (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 54g, and GC purity is 97.1%.
Embodiment 5
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (260g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 100 ℃, bromination reaction liquid slowly drips 30%H
2o
280mL, drips 100-110 ℃ of process control temp (the slow heat release of dropping process), dropwises 110 ℃ of stirring reactions of rear temperature control 10 hours, and raw material reaction is complete, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add toluene (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 84g, and GC purity is 98.4%.
Embodiment 6
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (360g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 100 ℃, bromination reaction liquid slowly drips 30%H
2o
280mL, drips 100-110 ℃ of process control temp (the slow heat release of dropping process), dropwises 110 ℃ of stirring reactions of rear temperature control 10 hours, and raw material reaction is complete, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add toluene (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 76g, and GC purity is 97.3%.
Embodiment 7
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (260g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 100 ℃, bromination reaction liquid slowly drips 30%H
2o
260mL, drips 100-110 ℃ of process control temp (the slow heat release of dropping process), dropwises 110 ℃ of stirring reactions of rear temperature control 24 hours, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add methyl tertiary butyl ether (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 60g, and GC purity is 92.3%.
Embodiment 8
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (260g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 100 ℃, bromination reaction liquid slowly drips 30%H
2o
2120mL, drips 100-110 ℃ of process control temp (the slow heat release of dropping process), dropwises 110 ℃ of stirring reactions of rear temperature control 10 hours, and raw material reaction is complete, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add methyl tertiary butyl ether (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 87g, and GC purity is 98.3%.
Embodiment 9
The present embodiment provides a kind of synthetic method of 3-bromopyridine, and it comprises the steps:
60g pyridine and 100mL water are added in 500mL there-necked flask, stir the lower 40%HBr of dropping (260g drips process temperature control 20-30 ℃), after dropping, be stirred to molten clearly, obtain bromination reaction liquid;
After being heated to 100 ℃, bromination reaction liquid slowly drips 30%H
2o
2180mL, drips 100-110 ℃ of process control temp (the slow heat release of dropping process), dropwises 110 ℃ of stirring reactions of rear temperature control 10 hours, and raw material reaction is complete, obtains thick product;
Thick product is cooled to below 10 ℃, with the 3N NaOH aqueous solution, adjusts pH to pH=8, add ethyl acetate (350mL * 3) extraction, organic phase is used sodium sulfite aqueous solution backwash again, is extracted liquid (organic phase);
Underpressure distillation after extraction liquid (organic phase) is concentrated, obtains 3-bromopyridine 81g, and GC purity is 97.5%.
Therefore, the inventive method is with some cheapnesss, the reagent that is easy to get, only need 1 step to react corresponding conversion, and do not need High Temperature High Pressure, synthetic route is easy and simple to handle simultaneously, there is no complicated last handling process, reduced production cost, this also makes the inventive method have good prospects for commercial application.
Claims (7)
1. a synthetic method for 3-bromopyridine, it comprise pyridine is mixed with hydrobromic acid solution after under hydrogen peroxide effect reaction generate thick product, then through purifying, obtain the step of 3-bromopyridine.
2. the synthetic method of 3-bromopyridine according to claim 1, it comprises the steps:
After pyridine is mixed with water, then mix with HBr solution, under the condition of 0-40 ℃, be stirred to molten clearly, obtain bromination reaction liquid, wherein, in weight part, pyridine: water: HBr solution=1: 1.67: (2.5-6);
Bromination reaction liquid is mixed at 70 ℃-120 ℃ with hydrogen peroxide solution, then, at 80 ℃-120 ℃ reaction 1h-48h, obtain thick product, wherein, in weight part, pyridine: hydrogen peroxide solution=1: (1.5-4);
With the aqueous sodium hydroxide solution of 3N, adjust pH to alkalescence thick product, then use organic solvent extraction, be extracted liquid;
Underpressure distillation after extraction liquid is concentrated, obtains 3-bromopyridine.
3. the synthetic method of 3-bromopyridine according to claim 2, is characterized in that: in weight part, and pyridine: hydrogen peroxide solution=1: (1.5-3).
4. the synthetic method of 3-bromopyridine according to claim 2, is characterized in that: the concentration of described HBr solution is 35%-48%.
5. the synthetic method of 3-bromopyridine according to claim 2, is characterized in that: the concentration of described hydrogen peroxide solution is 25%-35%.
6. the synthetic method of 3-bromopyridine according to claim 2, is characterized in that: described organic solvent comprises one or more the combination in ethyl acetate, methylene dichloride, toluene and methyl tertiary butyl ether.
7. the 3-bromopyridine that the synthetic method of the 3-bromopyridine described in claim 1-6 any one obtains.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104974081A (en) * | 2015-06-25 | 2015-10-14 | 洪帅金 | Synthetic method of 3-bromopyridine |
| CN112125839A (en) * | 2020-10-13 | 2020-12-25 | 安徽国星生物化学有限公司 | 3-bromopyridine continuous synthesis process and device |
| CN113461622A (en) * | 2021-08-11 | 2021-10-01 | 海正药业南通有限公司 | Synthesis method of Favipiravir intermediate 6-bromo-3-hydroxypyrazine-2-formamide |
| CN114591250A (en) * | 2022-03-19 | 2022-06-07 | 杭州布朗生物医药科技有限公司 | One-step synthesis method of 5-bromo-2-chloropyrimidine |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104974081A (en) * | 2015-06-25 | 2015-10-14 | 洪帅金 | Synthetic method of 3-bromopyridine |
| CN112125839A (en) * | 2020-10-13 | 2020-12-25 | 安徽国星生物化学有限公司 | 3-bromopyridine continuous synthesis process and device |
| CN113461622A (en) * | 2021-08-11 | 2021-10-01 | 海正药业南通有限公司 | Synthesis method of Favipiravir intermediate 6-bromo-3-hydroxypyrazine-2-formamide |
| WO2023015811A1 (en) * | 2021-08-11 | 2023-02-16 | 浙江海正药业股份有限公司 | Method for synthesizing favipiravir intermediate 6-bromo-3-hydroxypyrazine-2-formamide |
| CN113461622B (en) * | 2021-08-11 | 2023-04-07 | 海正药业南通有限公司 | Synthesis method of Favipiravir intermediate 6-bromo-3-hydroxypyrazine-2-formamide |
| CN114591250A (en) * | 2022-03-19 | 2022-06-07 | 杭州布朗生物医药科技有限公司 | One-step synthesis method of 5-bromo-2-chloropyrimidine |
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