CN101591328A - The chemical synthesis process of a kind of 2-bromothiophene and derivative thereof - Google Patents
The chemical synthesis process of a kind of 2-bromothiophene and derivative thereof Download PDFInfo
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- CN101591328A CN101591328A CNA2009101461292A CN200910146129A CN101591328A CN 101591328 A CN101591328 A CN 101591328A CN A2009101461292 A CNA2009101461292 A CN A2009101461292A CN 200910146129 A CN200910146129 A CN 200910146129A CN 101591328 A CN101591328 A CN 101591328A
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Abstract
The invention discloses a kind of structure suc as formula the 2-bromothiophene shown in (II) and the chemical synthesis process of derivative thereof: with structure suc as formula the thiophene or derivatives thereof shown in (I) and organic solvent mixes and controlled temperature at-50～20 ℃, add bromizating agent, finish insulation reaction, fully water-yielding stratum is divided in the reaction back, and organic layer concentrates, distillation promptly obtains 2-bromothiophene or derivatives thereof product; It is one of following that described bromizating agent is selected from: 1. tribromide pyridine, 2. the mixture of pyridine compounds and their and bromine, 3. the mixture of pyridine compounds and their, bromine and hydrogen peroxide, 4. pyridine compounds and their, bromine, hydrogen peroxide and hydrobromic mixture, 5. the mixture of pyridine compounds and their, Hydrogen bromide and hydrogen peroxide, 6. pyridine compounds and their, bromine and Hydrogen bromide; Described organic solvent is methylene dichloride or chloroform or ethylene dichloride.The present invention has advantages such as raw material is cheap and easy to get, toxicity is little, selectivity of chemical equation is high, yield is high, good product quality, the recyclable utilization of bromizating agent.
Description
One, technical field
The present invention relates to the chemical synthesis process of a kind of 2-bromothiophene and derivative thereof, be specifically related to the bromination process of a kind of thiophene and derivative thereof.
Two, background technology
2-bromothiophene and derivative thereof are the intermediates of a key using in the organic synthesis process, are all using this compounds, its of many uses having some idea of in a large amount of thiophene-based product building-up processes.Thereby effectively Synthetic 2-bromothiophene and derivative thereof seem even more important, forefathers have also done number of research projects from aspects such as bromizating agent and choice of Solvent: carry out bromination from employing Br2/CH3COOH early, but its bromination selectivity and yield are relatively poor, afterwards, change the research of other bromination combinations over to:
Document 1[Convenient synthetic procedures for 2-bromothiopheneXiangtan Daxue Ziran Kexue Xuebao, 20 (3), 92-93 (English) 1998] be bromizating agent to cross the pyridinium bromide hydrobromate, adopt thiophene single bromination in tetracol phenixin to obtain certain effect, productive rate is about 90%, but product purity is not high, is generally 98%, thereby simultaneously owing to used the bigger tetracol phenixin of toxicity to make its popularization be subjected to bigger restriction.
Document 2[Ishizaki, Masahiko; Takenaka, Junji (Tokuyama Kk, Japan) .Jpn.Kokai Tokkyo Koho JP 07242657 A2 19 Sep 1995 Heisei, 5 pp. (Japan)] use bromine and glycol dimethyl ether in chloroform solvent, to react generation 75%2-bromothiophene, its yield is on the low side, the large usage quantity of its bromine of while, the HBr of generation is not recycled preferably and is lost, and does not meet Atom economy.
Document 3[OH SE-HWA; JUNG JAE-YUN; PARK HEE-MOON; PARK SOO-YUL; KR960016128 (B1), 1996-12-04] adopt hydrogen peroxide and hydrobromic acid solution or hydrogen peroxide, Hydrogen bromide and bromine to mix as bromizating agent, but all exist reaction thorough inadequately, reaction preference is poor, cause product purity on the low side, general purity is 95-98%.
Three, summary of the invention
The technical problem to be solved in the present invention is to provide a kind of new Synthetic 2-bromothiophene and the bromination process of derivative thereof, and this method raw material is cheap and easy to get, toxicity is little, selectivity of chemical equation height, yield height, good product quality.
For solving the problems of the technologies described above, the technical solution used in the present invention is as follows:
A kind of structure is suc as formula the 2-bromothiophene shown in (II) and the chemical synthesis process of derivative thereof: with structure suc as formula the thiophene or derivatives thereof shown in (I) and organic solvent mixes and controlled temperature at-50～20 ℃, add bromizating agent, finish insulation reaction, fully water-yielding stratum is divided in the reaction back, and organic layer concentrates, distillation promptly obtains 2-bromothiophene or derivatives thereof product; It is one of following that described bromizating agent is selected from: 1. tribromide pyridine, 2. the mixture of pyridine compounds and their and bromine, 3. the mixture of pyridine compounds and their, bromine and hydrogen peroxide, 4. pyridine compounds and their, bromine, hydrogen peroxide and hydrobromic mixture, 5. the mixture of pyridine compounds and their, Hydrogen bromide and hydrogen peroxide, 6. pyridine compounds and their, bromine and hydrobromic mixture; Described organic solvent is methylene dichloride, chloroform or ethylene dichloride.Described ethylene dichloride can be 1,1-ethylene dichloride or 1,2-ethylene dichloride.
Reaction formula is as follows:
In formula (I), the formula (II), R is the alkyl of H or C1～C6.
Further, organic solvent of the present invention chloroform most preferably.
Bromizating agent of the present invention is preferred one of following: the 3. mixture of pyridine compounds and their, bromine and hydrogen peroxide, 4. pyridine compounds and their, bromine, hydrogen peroxide and hydrobromic mixture, the 5. mixture of pyridine compounds and their, Hydrogen bromide and hydrogen peroxide.Use under the situation of above-mentioned bromizating agent, reaction finishes and can add hydrogen peroxide in the water layer of telling or bromine makes new bromizating agent recycling.
Wherein 2.～6. bromizating agent used in the present invention is mixture.Described pyridine compounds and their can be pyridine or alkyl pyridine, and described alkyl pyridine can be 2-picoline, 3-picoline, 4-picoline, 2,4-lutidine etc., and most preferred pyridine compounds and their is a pyridine.Described hydrogen peroxide and Hydrogen bromide generally add with the form of the aqueous solution, do not have special requirement for both concentration, and the hydrobromic acid aqueous solution of the hydrogen peroxide of general commercially available various mass concentrations and commercially available various mass concentrations all is suitable for.
2.～5. bromizating agent of the present invention can prepare in advance, also each component of bromizating agent directly can be joined in the reaction system.The preparation in advance of bromizating agent generally also is a controlled temperature at-50～20 ℃ (preferred-20～10 ℃), and each component is mixed back insulation reaction certain hour, need not to separate promptly obtaining described bromizating agent.The content that can participate in the bromine atoms (being effective bromine) of the bromination reaction of thiophene derivant in the bromizating agent of the present invention determines that by bromine, hydrogen peroxide and hydrobromic content in the bromizating agent those skilled in the art can make up according to practical situation.The content of the pyridine compounds and their in the bromizating agent component is not done special requirement, and the present invention specifically recommends the mol ratio of pyridine compounds and their in the bromizating agent and effective bromine 1.0～1.5: 1.
Thiophene or derivatives thereof self also can be used as solvent among the present invention, the effective bromine in the described in general bromizating agent and the mol ratio of thiophene or derivatives thereof are 0.1～2: 1 this scope all can, the effective bromine in the preferred described bromizating agent and the mol ratio of thiophene or derivatives thereof are 0.7～1.0: 1.
Volume of organic solvent consumption of the present invention is recommended as 50～2000ml/mol in the mole number of thiophene or derivatives thereof, preferred 200～500ml/mol.
Further, bromination reaction of the present invention preferably is controlled under-20～10 ℃ of temperature and carries out.
The present invention time of the reinforced back insulation reaction that finishes generally at 0.1～10 hour, preferred 0.5～2 hour.
The present invention is fully reacting the back standing demix, and the separation of gained organic layer obtains product, the recyclable bromizating agent of the water layer of telling.
Compared with prior art, beneficial effect of the present invention is:
A) the present invention is by repeated screening, determine methylene dichloride that toxicity is less or chloroform as reaction solvent of the present invention, improved the selectivity of reaction, made reaction yield and product purity all be significantly improved, wherein productive rate can be up to more than 95%, and product purity is generally all more than 99%.
B) the present invention makes reaction preference improve greatly by using specific bromizating agent.Especially by in bromizating agent, adding hydrogen peroxide, make the bromine atoms utilization ratio improve greatly; And bromizating agent can reclaim easily, can obtain new bromizating agent by adding hydrogen peroxide or bromine in the water layer that contains pyridine and bromide anion that obtains and come into operation again after reaction.Because therefore the bromine price will greatly reduce production cost far above the hydrogen peroxide price, has reduced three waste discharge simultaneously.
Four, specific embodiment
With specific embodiment technical scheme of the present invention is described further below, but protection scope of the present invention is not limited thereto:
Embodiment 1
In three mouthfuls of reaction flasks of 1000ml, add thiophene 95g (1.131mol), chloroform 300ml, open and stir, be cooled to-5 ℃, under agitation slowly drop into the about 320g of tribromide pyridine (1mol) in batches, adding finishes, and continues insulation reaction 0.5 hour, adds the about 100ml of water then, stirred 0.5 hour, leave standstill branch vibration layer, organic layer is concentrated into dried, and the concentrated solution rectification under vacuum obtains 2-bromothiophene 148g (0.908mol), yield is 90.8%, and content is 99.5%.
Embodiment 2
In three mouthfuls of reaction flasks of 1000ml, add thiophene 95g (1.131mol), normal hexane 300ml, 2-picoline 101g (1.0mol) and 48% hydrobromic acid aqueous solution 337.5g (2mol), open and stir, be cooled to-10 ℃, Dropwise 35 % hydrogen peroxide 97.1g (1.0mol) slowly under agitation, adding finishes, continued insulation reaction 0.5 hour, leave standstill branch vibration layer, organic layer is concentrated into dried, and the concentrated solution rectification under vacuum obtains 2-bromothiophene 138.5g (0.85mol), yield is 85%, and content is 98.8%.
Embodiment 3
In three mouthfuls of reaction flasks of 1000ml, add thiophene 100g (1.1905mol), methylene dichloride 300ml, pyridine 79g (1.0mol) and 35% hydrogen peroxide 48.6g (0.5mol), open and stir, be cooled to-10 ℃, under agitation slowly drip bromine 80g (0.5mol), adding finishes, continued insulation reaction 0.5 hour, leave standstill branch vibration layer, organic layer is concentrated into dried, and the concentrated solution rectification under vacuum obtains 2-bromothiophene 145g (0.8896mol), yield is 88.96%, and content is 99.2%.
Embodiment 4
In three mouthfuls of reaction flasks of 1000ml, add 3 methyl thiophene 98g (1.0mol), chloroform 300ml and open stirring, be cooled to-5 ℃, under agitation slowly drip bromizating agent with following method preparation, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 3-methyl-2-bromothiophene 151.3 (0.855mol), and yield is 95%, and content is 99.5%.
Bromizating agent preparation method: in the 500ml bottle, add pyridine 71.1g (0.9mol) and 506.2g 48% hydrobromic acid solution (3mol), be cooled to 0 ℃, slowly Dropwise 35 % hydrogen peroxide 87.4g (0.9mol), dropwise, continued insulation reaction 1 hour, and need not to separate, reaction solution is stand-by.
Embodiment 5
In three mouthfuls of reaction flasks of 1000ml, add thiophene 95g (1.131mol), tetracol phenixin 300ml and open stirring, be cooled to 10 ℃, under agitation slowly drip bromizating agent with method preparation among the embodiment 4, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 2-bromothiophene 133.6g (0.82mol), and yield is 82%, and content is 98.5%.
Embodiment 6
In three mouthfuls of reaction flasks of 1000ml, add 3 methyl thiophene 98g (1.0mol), normal hexane 500ml and open stirring, be cooled to-5 ℃, under agitation slowly drip the bromizating agent that adopts the preparation of embodiment 4 methods, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 3-methyl-2-bromothiophene 139.4g (0.7876mol), and yield is 87.5%, and content is 99.5%.
Embodiment 7
In three mouthfuls of reaction flasks of 1000ml, add 2 acetyl thiophene 112g (1.0mol), chloroform 300ml and open stirring, be cooled to 0 ℃, under agitation slowly drip bromizating agent with the preparation of embodiment 4 methods, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 5-ethyl-2-bromothiophene 165.9g (0.8685mol), and yield is 96.5%, and content is 99.4%.
Embodiment 8
In three mouthfuls of reaction flasks of 1000ml, add thiophene 95g (1.131mol), methylene dichloride 300ml and open stirring, be cooled to-15 ℃, under agitation slowly drip bromizating agent with following method preparation, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer (water layer is continued to employ), organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 2-bromothiophene 151.6g (0.93mol), and yield is 93%, and content is 99.5%.
Bromizating agent preparation method: in the 500ml bottle, add pyridine 71.1g (1.0mol) and 337.5g 48% hydrobromic acid solution (2mol), be cooled to 0 ℃, slowly drip bromine 160g (1.0mol), dropwise, continued insulation reaction 1 hour, and need not to separate, reaction solution is stand-by.
Embodiment 9
In three mouthfuls of reaction flasks of 1000ml, add 2-thiotolene 98g (1.0mol), chloroform 300ml and open stirring, be cooled to 0 ℃, under agitation slowly drip bromizating agent with the preparation of embodiment 8 methods, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 5-methyl-2-bromothiophene 152.1g (0.8595mol), and yield is 95.5%, and content is 99.6%.
Embodiment 10
In three mouthfuls of reaction flasks of 1000ml, add thiophene 95g (1.131mol), methylene dichloride 300ml and open stirring, be cooled to-5 ℃, under agitation slowly drip the bromizating agent that reclaims preparation with following method, adding finishes, and continues insulation reaction 0.5 hour, leaves standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 2-bromothiophene 151.6g (0.93mol), and yield is 93%, and content is 99.5%.
The recoverying and utilizing method of bromizating agent: with the water layer of telling among the embodiment 8, be cooled to 5 ℃,, dropwise, continued stirring reaction 0.5 hour, need not to separate, directly use as bromizating agent to the hydrogen peroxide 97.1g (1mol) of Dropwise 35 % slowly wherein.
Embodiment 11
In three mouthfuls of reaction flasks of 1000ml, add thiophene 100g (1.1905mol), methylene dichloride 300ml, pyridine 79g (1.0mol) and 35% hydrogen peroxide 41.8g (0.42mol), open and stir, be cooled to-10 ℃, under agitation slowly drip bromine 67.2g (0.42mol), adding finishes, continued insulation reaction 0.5 hour, leave standstill branch vibration layer, organic layer is concentrated into dried, and the concentrated solution rectification under vacuum obtains 2-bromothiophene 125g (0.7669mol), yield is 91.29%, and content is 99.3%.
Embodiment 12
In three mouthfuls of reaction flasks of 1000ml, add 3 methyl thiophene 98g (1.0mol), 1,2-ethylene dichloride 500ml, pyridine 60g (0.7595mol), 48% hydrobromic acid aqueous solution 700g (4.15mol) open stirring, be cooled to-5 ℃, under agitation slowly drip 27.5% hydrogen peroxide 117.45g (0.95mol), adding finishes, continued insulation reaction 0.5 hour, leave standstill branch vibration layer, organic layer is concentrated into dried, the concentrated solution rectification under vacuum obtains 3-methyl-2-bromothiophene 156.2g (0.8825mol), yield is 92.9%, and content is 99.5%.
Claims (10)
1, a kind of structure is suc as formula the 2-bromothiophene shown in (II) and the chemical synthesis process of derivative thereof, described synthetic method is as follows: structure is mixed suc as formula the thiophene or derivatives thereof shown in (I) and organic solvent and controlled temperature at-50～20 ℃, add bromizating agent, finish insulation reaction, fully water-yielding stratum is divided in the reaction back, and organic layer concentrates, distillation promptly obtains 2-bromothiophene or derivatives thereof product; It is one of following that described bromizating agent is selected from: 1. tribromide pyridine, 2. the mixture of pyridine compounds and their and bromine, 3. the mixture of pyridine compounds and their, bromine and hydrogen peroxide, 4. pyridine compounds and their, bromine, hydrogen peroxide and hydrobromic mixture, 5. the mixture of pyridine compounds and their, Hydrogen bromide and hydrogen peroxide, 6. pyridine compounds and their, bromine and Hydrogen bromide; Described organic solvent is methylene dichloride or chloroform or ethylene dichloride;
Formula (I) or (II) in, R is the alkyl of H or C1～C6.
2, the chemical synthesis process of 2-bromothiophene as claimed in claim 1 and derivative thereof is characterized in that described organic solvent is a chloroform.
3, the chemical synthesis process of 2-bromothiophene as claimed in claim 1 or 2 and derivative thereof, it is one of following to it is characterized in that described bromizating agent is selected from: the 3. mixture of pyridine compounds and their, bromine and hydrogen peroxide, 4. pyridine compounds and their, bromine, hydrogen peroxide and hydrobromic mixture, the 5. mixture of pyridine compounds and their, Hydrogen bromide and hydrogen peroxide.
4, the chemical synthesis process of 2-bromothiophene as claimed in claim 3 and derivative thereof adds hydrogen peroxide or bromine and makes new bromizating agent recycling in the water layer that it is characterized in that telling.
5, the chemical synthesis process of 2-bromothiophene as claimed in claim 1 or 2 and derivative thereof is characterized in that described pyridine compounds and their is pyridine, 2-picoline, 3-picoline, 4-picoline or 2, the 4-lutidine.
6, the chemical synthesis process of 2-bromothiophene as claimed in claim 5 and derivative thereof is characterized in that described pyridine compounds and their is a pyridine.
7, the chemical synthesis process of 2-bromothiophene as claimed in claim 1 or 2 and derivative thereof is characterized in that the effective bromine in the described bromizating agent and the mol ratio of thiophene or derivatives thereof are 0.1～2: 1.
8, the chemical synthesis process of 2-bromothiophene as claimed in claim 1 or 2 and derivative thereof is characterized in that the described insulation reaction time is 0.1～10 hour.
9, the 2-bromothiophene of stating as claim 1 or 2 and the chemical synthesis process of derivative thereof is characterized in that controlled temperature is at-20～10 ℃.
10, the chemical synthesis process of 2-bromothiophene as claimed in claim 1 or 2 and derivative thereof is characterized in that in the described bromizating agent that effectively the mol ratio of bromine and thiophene or derivatives thereof is 0.7～1.0: 1.
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| CNA2009101461292A CN101591328A (en) | 2009-05-04 | 2009-06-08 | The chemical synthesis process of a kind of 2-bromothiophene and derivative thereof |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103497172A (en) * | 2013-10-15 | 2014-01-08 | 连云港宏业化工有限公司 | Synthetic method of 2-chlorothiophene |
| CN103819449A (en) * | 2014-02-20 | 2014-05-28 | 常州市正锋光电新材料有限公司 | Preparation method for 2-bromothiophene |
| CN107935985A (en) * | 2017-12-25 | 2018-04-20 | 中山市得高行知识产权中心（有限合伙） | A kind of synthetic method of 2 bromothiophene |
| CN112010831A (en) * | 2020-09-08 | 2020-12-01 | 上海生农生化制品股份有限公司 | Green and efficient phenyl ether ketal bromination synthesis method |
| CN116273076A (en) * | 2022-11-30 | 2023-06-23 | 安达市海纳贝尔化工有限公司 | Method for improving yield of 2-bromothiophene by surface oxygen vacancy enrichment BiOBr hollow microsphere photocatalyst |
-
2009
- 2009-06-08 CN CNA2009101461292A patent/CN101591328A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103497172A (en) * | 2013-10-15 | 2014-01-08 | 连云港宏业化工有限公司 | Synthetic method of 2-chlorothiophene |
| CN103819449A (en) * | 2014-02-20 | 2014-05-28 | 常州市正锋光电新材料有限公司 | Preparation method for 2-bromothiophene |
| CN107935985A (en) * | 2017-12-25 | 2018-04-20 | 中山市得高行知识产权中心（有限合伙） | A kind of synthetic method of 2 bromothiophene |
| CN112010831A (en) * | 2020-09-08 | 2020-12-01 | 上海生农生化制品股份有限公司 | Green and efficient phenyl ether ketal bromination synthesis method |
| CN116273076A (en) * | 2022-11-30 | 2023-06-23 | 安达市海纳贝尔化工有限公司 | Method for improving yield of 2-bromothiophene by surface oxygen vacancy enrichment BiOBr hollow microsphere photocatalyst |
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Application publication date: 20091202 |