CN1544432A - 2-acetyl thiophene synthetic method using thiophene in crude benzene as material - Google Patents
2-acetyl thiophene synthetic method using thiophene in crude benzene as material Download PDFInfo
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- CN1544432A CN1544432A CNA2003101152681A CN200310115268A CN1544432A CN 1544432 A CN1544432 A CN 1544432A CN A2003101152681 A CNA2003101152681 A CN A2003101152681A CN 200310115268 A CN200310115268 A CN 200310115268A CN 1544432 A CN1544432 A CN 1544432A
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Abstract
The invention provides a process for synthesizing 2- acetyl thiophene pharmaceutical intermediate compound by using thiophene in crude benzole through selective acetylation reaction, wherein an extraction and distillation method is adopted to condensate the thiophene in carbonized crude benzole, and to further prepare acetyl thiophene pharmaceutical intermediate compound from the thiophene concentrate through catalytic conversion.
Description
Technical field
The present invention relates to iron and steel enterprise and coking enterprise in Industrial processes the deep processing and the utilization of the byproduct that produces----crude benzol; specifically, relate to a kind of with crude benzol through the prefractionation unit, the extracting rectifying thiophene enriched material that obtains in two-stage extracting rectifying unit is the method for the further Synthetic 2-acetyl thiophene of raw material.
Background technology
The 2-acetyl thiophene is the intermediate of synthesizing new broad-spectrum antibiotics cephalosporin.Synthetic 2-acetyl thiophene all adopts the higher thiophene of purity as raw material both at home and abroad.Because the very expensive and complicated process of preparation of high purity thiophene price, thereby cause this class intermediate and generally higher by the cost of this intermediate synthetic broad-spectrum antibiotics.
The method of present domestic Synthetic 2-acetyl thiophene mainly is that its chemical equation is by industrial thiophene (content is greater than 95%) and aceticanhydride synthetic obtaining under the katalysis of phosphoric acid:
Technological process is: aceticanhydride, 85% phosphoric acid and thiophene are dropped in the reactor, stir, progressively being heated to reflux temperature is 96～97 ℃, keeps backflow 2h, and reaction finishes, with reaction product cooling, washing, branch vibration layer; The gained oil reservoir is carried out normal pressure, underpressure distillation, collect and to steam thing, leave standstill, branch vibration layer, reclaim the intact thiophene of unreacted.Residual oily matter is collected 89～90 ℃ of (1333Pa) cuts and is promptly got 2-acetyl thiophene finished product through underpressure distillation in the pot.
In China, thiophene mainly is to obtain in the treating process of coal tar, but at present domestic except the large-scale coal chemical enterprise employing of minority shortening method, most enterprises all adopt acid wash art breading coking crude benzene.The shortening method adopts Co-Mo series hydrogenation catalyst under 350-400 ℃, 2.5-6.0MPa condition that the thiophene hydrogenation is saturated and then be converted into the purpose that hydrogen sulfide reaches desulfurization, and thiophene is destroyed and can't reclaim this resource; Sulfuric acid scrubbing method technology then adopts thiophene and vitriolic sulfonation reaction that thiophene is converted into thiophene-sulfonic acid, and then reach the purpose of refining coking benzene, though thiophene-sulfonic acid can obtain the thiophene product by the laggard one-step refining of hydrolysis, but this technology is flow process complexity, high pollution, high flow rate not only, topmost shortcoming is that the thiophene rate of recovery is very low, of poor benefits.
For above-mentioned reasons, cause domestic thiophene resource very in short supply, the higher thiophene of the external purity of the main dependence on import of production thiophene-based pharmacy intermediate is as the present situation of raw material.
Summary of the invention
Purpose of the present invention just is to avoid above-mentioned shortcoming and defect, proposes a kind of raw material and is easy to get, and preparation cost is low, the added value height, and process approach is simple, the preparation method of the 2-acetyl thiophene that equipment corrosion and environmental pollution degree are little.
Purpose of the present invention can reach by following measure:
The present invention adopts " a kind of method that is prepared high pure benzene and concentrated thiophene by crude benzol " that the applicant develops, and (Chinese patent application number is: method 03140545.2), coking crude benzene with China's coking industry by-product, adopt the petrochemical complex isolation technique when producing purified petroleum benzin, reclaim valuable thiophene resource.
At first: will be from the byproduct-crude benzol of coking industry and iron and steel enterprise through a series of rectifyinges, behind benzene front-end volatiles in the excision crude benzol raw material, heavy constituent (naphthalene solvent oil), the coumarone cut, obtain the coking-light benzene cut, promptly contain the benzene-toluene-dimethylbenzene mixed fraction of thiophene.Adopt the method for two-stage extracting rectifying, is raw material through narrow benzene cut that contains thiophene or the coking-light benzene that the distillation cutting obtains through the benzene-toluene fraction that contains thiophene that the distillation cutting obtains with coking-light benzene or coking-light benzene, obtain containing thiophene concentration through the one-level extracting rectifying and meet the coking benzene product that is not less than GB planned quality of the product secondary standard and the enriched material of thiophene, and then further concentrate, and then obtain the thiophene product of higher concentration through the thiophene enriched material that the secondary extracting rectifying obtains the one-level extracting rectifying.
Then: the thiophene enriched material that contains the finite concentration thiophene with recovery is a raw material; phosphoric acid with 85%; polyphosphoric acid; liquid acid such as sulfuric acid; H β; HZSM-5; HY; USY; zeolite molecular sieves such as HM; strong-acid ion exchange resin; atlapulgite; Zinc Chloride Anhydrous; iron trichloride etc. contain Bronsted acid and (or) Lewis acid is catalyzer; diacetyl oxide or Acetyl Chloride 98Min. are acetylation reagent; at 25 ℃～100 ℃; the mol ratio of normal pressure and thiophene and acetoxylation reagent is under 0.1～50 the condition; thiophene is converted into the 2-acetyl thiophene; benzene and acetic acid fraction (its azeotropic point is 92.6 ℃) and the intact acetylation reagent of unreacted wherein removed in reaction product first rectifying under normal pressure; and then through being decompressed to 65mmHg; cut 129 ℃-131 ℃, rectifying separation goes out purity and is not less than 99.0% 2-acetyl thiophene.
The present invention has following advantage compared to existing technology: the raw material that the present invention adopts is the enriched material of the by product thiophene in the coked crude benzene refining process, it is low to have solved the acid wash thiophene rate of recovery, equipment corrosion is serious, waste treatment reaches problem of environmental pollution more, has also avoided the destruction of shortening method to the thiophene resource of preciousness simultaneously; And the enriched material of thiophene needn't be through complicated treating process, can be directly by acetylize Synthetic 2-acetyl thiophene intermediate, and technical process is simple, and cost is low, and environment is not constituted destruction, the added value height of products obtained therefrom, genus environmentally friendly technology.
Embodiment
The method that obtains the thiophene enriched material is referring to patent " a kind of method that is prepared purified petroleum benzin and concentrated thiophene by crude benzol ", and application number is 03140545.2.Detailed process is as described below:
One-level extracting rectifying: with N-Methyl pyrrolidone; N; dinethylformamide; the N-formyl morpholine; glycol; tetramethylene sulfone etc.; coking-light benzene or the coking-light benzene that contains finite concentration thiophene sulfide cut benzene through narrow benzene cut or the coking-light benzene that the distillation cutting obtains through distillation; the toluene mixed fraction is that raw material carries out the one-level extracting rectifying; tower bottom flow stock-traders' know-how solvent recovery tower rectifying separation obtains preliminary spissated thiophene product; thiophene concentration is in 0.5% (weight)-30% (weight) scope; this logistics also can directly adopt this thiophene enriched material to carry out acetylization reaction Synthetic 2-acetyl thiophene intermediate as the raw material of secondary extracting rectifying.
The secondary extracting rectifying: the thiophene enriched material that obtains with the one-level extracting rectifying is a raw material, through the secondary extracting rectifying, thiophene product after tower bottom flow stock-traders' know-how solvent recovery tower rectifying separation obtains further concentrating, secondary extractive distillation column overhead benzene cut contains a certain amount of thiophene, this stream thigh turns back to the one-level extractive distillation column, further reclaims thiophene as one-level extracting rectifying part of raw materials.The thiophene enriched material concentration range that obtains behind the two-stage extracting rectifying is generally between 2% (weight)-98% (weight); this thiophene enriched material can directly carry out highly selective acylation Synthetic 2-acetyl thiophene intermediate to thiophene is further refining; certainly; also can obtain the thiophene product that quality meets GB, carry out the synthetic of above-mentioned thiophene intermediate then this thiophene enriched material is further refining.
Below in conjunction with embodiment, the present invention is further specified:
Embodiment one:
With the coking-light benzene that contains the 3350mg/L thiophene is raw material; the method that adopts " a kind of method that is prepared purified petroleum benzin and concentrated thiophene by crude benzol " patent introduction is a raw material through thiophene-benzole soln that one-level and two-stage extracting rectifying obtain containing thiophene 1.98% (weight) and 19.5% (weight) respectively; phosphoric acid with 85%; the H beta-zeolite molecular sieve; strong-acid ion exchange resin; atlapulgite; dry oxidation zinc; iron trichloride is a catalyzer; diacetyl oxide is an acetylation reagent; at 40 ℃-90 ℃; the mol ratio of normal pressure and diacetyl oxide and thiophene is under 2 the condition; thiophene is converted into the 2-acetyl thiophene, and the thiophene transformation efficiency of different catalysts and the selectivity of 2-acetyl thiophene see Table 1: the reaction result of table 1 different catalysts catalysis thiophene and diacetyl oxide Synthetic 2-acetyl thiophene (raw material contains thiophene 1.98%)
Catalyst reaction temperatures ℃ material agent ratio
*Mass space velocity (h
-1) thiophene transformation efficiency 2-acetyl thiophene selectivity (%)
(％)
85% phosphatase 79 0 10/＞99.0 98.5
Hβ 60 / 5 ＞99.0 99.2
Highly acidic resin 40/2.5＞99.0 99.0
Atlapulgite 80/2.5 83.0 99.0
Zinc Chloride Anhydrous 40 10/＞99.0 98.0
Iron trichloride 40 10/＞99.0 98.0
Benzene and acetic acid fraction (its azeotropic point is 92.6 ℃) and the intact diacetyl oxide of unreacted wherein removed in reaction product first rectifying under normal pressure; and then cut 129 ℃-131 ℃ (65mmHg) through rectification under vacuum, isolate purity and be not less than 99.0% 2-acetyl thiophene.
Embodiment two:
Adopting the embodiment 1 related benzole soln that contains thiophene 19.5% is raw material; phosphoric acid with 85%, polyphosphoric acid, H beta-zeolite molecular sieve, strong-acid ion exchange resin, Zinc Chloride Anhydrous, iron trichloride are catalyzer; diacetyl oxide is an acetylation reagent; be under 3 the condition in the mol ratio of 40 ℃-90 ℃, normal pressure and diacetyl oxide and thiophene; thiophene is converted into the 2-acetyl thiophene, and the thiophene transformation efficiency of different catalysts and the selectivity of 2-acetyl thiophene see Table 2:
The reaction result of table 2 different catalysts catalysis thiophene and diacetyl oxide Synthetic 2-acetyl thiophene
Catalyst reaction temperatures ℃ material agent ratio
*Mass space velocity (h
-1) thiophene transformation efficiency 2-acetyl thiophene selectivity (%)
(％)
85% phosphatase 79 0 15/＞99.0 99.2
Polyphosphoric acid 90 15/＞99.0 98.8
Hβ 60 / 6 ＞97.1 99.5
Highly acidic resin 40/5＞99.0 98.6
Zinc Chloride Anhydrous 40 15/＞99.0 99.1
Benzene and acetic acid fraction (its azeotropic point is 92.6 ℃) and the intact diacetyl oxide of unreacted wherein removed in reaction product first rectifying under normal pressure; and then cut 129 ℃-130 ℃ (65mmHg) through rectification under vacuum, isolate purity and be not less than 99.0% 2-acetyl thiophene.
Embodiment three:
With the coking-light benzene that contains the 4250mg/L thiophene is raw material; the technological process that adopts " a kind of method that is prepared purified petroleum benzin and concentrated thiophene by crude benzol " patent introduction is a raw material through thiophene-benzole soln that the two-stage extracting rectifying obtains containing thiophene 24% (weight); phosphoric acid with 85%; the H beta-zeolite molecular sieve; strong-acid ion exchange resin; atlapulgite; Zinc Chloride Anhydrous; iron trichloride is a catalyzer; diacetyl oxide is an acetylation reagent; at 40 ℃-90 ℃; the mol ratio of normal pressure and diacetyl oxide and thiophene is under 2 the condition; thiophene is converted into the 2-acetyl thiophene, and the thiophene transformation efficiency of different catalysts and the selectivity of 2-acetyl thiophene see Table 3:
The reaction result of table 3 different catalysts catalysis thiophene and diacetyl oxide Synthetic 2-acetyl thiophene
Catalyst reaction temperatures ℃ material agent ratio
*Mass space velocity (h
-1) thiophene transformation efficiency 2-acetyl thiophene selectivity (%)
(％)
85% phosphatase 79 0 10/＞99.0 98.0
Polyphosphoric acid 90 10/＞99.0 97.3
Hβ 60 / 12 ＞90.0 98.5
Highly acidic resin 40/2.5＞99.0 98.7
Atlapulgite 80/2.5 82.0 99.0
Zinc Chloride Anhydrous 40 10/＞99.0 97.0
Iron trichloride 40 10/＞99.0 97.5
Benzene and acetic acid fraction (its azeotropic point is 92.6 ℃) and the intact diacetyl oxide of unreacted wherein removed in reaction product first rectifying under normal pressure; and then cut 129 ℃-130 ℃ (65mmHg) through rectification under vacuum, isolate purity and be not less than 99.0% 2-acetyl thiophene.
Embodiment four:
With the 24% thiophene-benzole soln that contains that adopted among the embodiment 2 is raw material; strong-acid ion exchange resin, atlapulgite, Zinc Chloride Anhydrous, iron trichloride are catalyzer; Acetyl Chloride 98Min. is an acetylation reagent; be under 2 the condition in the mol ratio of 25 ℃ of room temperatures, normal pressure and Acetyl Chloride 98Min. and thiophene; thiophene is converted into the 2-acetyl thiophene, and the thiophene transformation efficiency of different catalysts and the selectivity of 2-acetyl thiophene see Table 4:
The reaction result of table 4 different catalysts catalysis thiophene and diacetyl oxide Synthetic 2-acetyl thiophene
Catalyzer material agent ratio
*Mass space velocity (h
-1) thiophene transformation efficiency 2-acetyl thiophene selectivity (%)
(％)
Highly acidic resin/2.5＞99.0 97.7
Atlapulgite/2.5 93.2 96.0
Zinc Chloride Anhydrous 10/＞99.0 97.0
Iron trichloride 10/＞99.0 97.5
Claims (9)
1, a kind of is the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol, it is characterized in that: the thiophene enriched material that obtains through solvent extraction rectifying with crude benzol is a raw material, through highly selective acylation reaction Synthetic 2-acetyl thiophene.
2, according to claim 1 is the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol; it is characterized in that: with liquid acid, solid acid etc. contain Bronsted and (or) acid of Lewis is catalyzer; thiophene enriched material and acetylation reagent carry out the highly selective acylation reaction; benzene and acetic acid fraction and the intact acetylation reagent of unreacted wherein removed in reaction product first rectifying under normal pressure; and then through being decompressed to 65mmHg, rectifying separation goes out purity and is not less than 99.0% 2-acetyl thiophene.
3; according to claim 1 is the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol; it is characterized in that: the raw material sources of Synthetic 2-acetyl thiophene in coking crude benzene through the prefractionation unit; cutter unit separates the benzene-toluene that the contains thiophene-dimethylbenzene mixed fraction that obtains; or the benzene cut that contains thiophene that obtains through fractionation by distillation of this mixed fraction; or the benzene-toluene fraction that contains thiophene that obtains through fractionation by distillation of this mixed fraction; through the one-level extracting rectifying and (or) thiophene enriched material that the secondary extracting rectifying obtains, wherein contain the thiophene concentration range and be generally 0.3% (weight)-99.99% (weight).
4, according to claim 3 is the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol; it is characterized in that: the thiophene enriched material obtains the higher thiophene product of concentration through further rectifying separation, wherein contains the thiophene concentration range and is generally 0.5% (weight)-99.99% (weight).
5, according to claim 1,2 described be the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol, it is characterized in that: highly selective acylation reaction Synthetic 2-acetyl thiophene catalyst system therefor is liquid acid such as 85% phosphoric acid, polyphosphoric acid, sulfuric acid; Zeolite molecular sieves such as H β, HZSM-5, HY, USY, HM; Strong-acid ion exchange resin, atlapulgite, Zinc Chloride Anhydrous, iron trichloride etc. contain the Bronsted acid site and (or) the Lewis acid site.
6, according to claim 1,2 described be the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol, it is characterized in that: the used acetylation reagent of highly selective acylation reaction Synthetic 2-acetyl thiophene is diacetyl oxide, Acetyl Chloride 98Min..
7, according to claim 1,2 described be the method for raw material Synthetic 2-acetyl thiophene with thiophene in the crude benzol, it is characterized in that: the weight proportion of catalyzer and thiophene is 1: 1～500.
8, according to claim 1,2 described be the method for raw material Synthetic 2-acetyl thiophene with thiophene in the coking-light benzene, it is characterized in that: the mol ratio of thiophene and acetoxylation reagent is 0.1～50.
9, according to claim 1,2 described be the method for raw material Synthetic 2-acetyl thiophene with thiophene in the coking-light benzene, it is characterized in that: temperature of reaction is 25 ℃～100 ℃, and reaction pressure is a normal pressure.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1295226C (en) * | 2004-11-18 | 2007-01-17 | 浙江工业大学 | Preparation method of acetyl thiophene |
| CN100402519C (en) * | 2004-12-18 | 2008-07-16 | 浙江工业大学 | Application of aluminum phosphotungstic acid in synthesizing catalyst of 2-acetyl thiophene |
| CN100402518C (en) * | 2004-12-30 | 2008-07-16 | 浙江工业大学 | Application of cesium phosphotungstic acid as catalyst for synthesizing acetyl thiophene |
| CN101157682B (en) * | 2007-11-09 | 2010-06-23 | 浙江工业大学 | Method for preparing acetyl thiophene |
| CN106831702A (en) * | 2016-12-05 | 2017-06-13 | 浙江燎原药业股份有限公司 | A kind of preparation method of the thiophenic acid of 5 substitution 2 |
| CN106892895A (en) * | 2017-03-06 | 2017-06-27 | 山西恒强化工有限公司 | A kind of preparation method of 2 acetyl thiophene |
| CN109195961A (en) * | 2016-03-24 | 2019-01-11 | 孟山都技术公司 | The method for being used to prepare heteroaryl carboxylic acid |
| CN111440140A (en) * | 2020-05-27 | 2020-07-24 | 甘肃盛世恒百药业有限公司 | Green process for synthesizing 2-acetylthiophene |
| CN112457290A (en) * | 2020-12-10 | 2021-03-09 | 武汉至精诚医药技术有限公司 | Synthetic method of 2-glyoxal-5-methylthiophene |
-
2003
- 2003-11-27 CN CNA2003101152681A patent/CN1544432A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1295226C (en) * | 2004-11-18 | 2007-01-17 | 浙江工业大学 | Preparation method of acetyl thiophene |
| CN100402519C (en) * | 2004-12-18 | 2008-07-16 | 浙江工业大学 | Application of aluminum phosphotungstic acid in synthesizing catalyst of 2-acetyl thiophene |
| CN100402518C (en) * | 2004-12-30 | 2008-07-16 | 浙江工业大学 | Application of cesium phosphotungstic acid as catalyst for synthesizing acetyl thiophene |
| CN101157682B (en) * | 2007-11-09 | 2010-06-23 | 浙江工业大学 | Method for preparing acetyl thiophene |
| CN109195961A (en) * | 2016-03-24 | 2019-01-11 | 孟山都技术公司 | The method for being used to prepare heteroaryl carboxylic acid |
| CN106831702A (en) * | 2016-12-05 | 2017-06-13 | 浙江燎原药业股份有限公司 | A kind of preparation method of the thiophenic acid of 5 substitution 2 |
| CN106892895A (en) * | 2017-03-06 | 2017-06-27 | 山西恒强化工有限公司 | A kind of preparation method of 2 acetyl thiophene |
| CN111440140A (en) * | 2020-05-27 | 2020-07-24 | 甘肃盛世恒百药业有限公司 | Green process for synthesizing 2-acetylthiophene |
| CN112457290A (en) * | 2020-12-10 | 2021-03-09 | 武汉至精诚医药技术有限公司 | Synthetic method of 2-glyoxal-5-methylthiophene |
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