CN101423467B - Method for synthesizing 2,5-acetonyl acetone - Google Patents
Method for synthesizing 2,5-acetonyl acetone Download PDFInfo
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- CN101423467B CN101423467B CN2008100797668A CN200810079766A CN101423467B CN 101423467 B CN101423467 B CN 101423467B CN 2008100797668 A CN2008100797668 A CN 2008100797668A CN 200810079766 A CN200810079766 A CN 200810079766A CN 101423467 B CN101423467 B CN 101423467B
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- hexanedione
- acetic acid
- dimethyl furan
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Abstract
The invention discloses a method for synthesizing 2, 5-hexanedione, which comprises the steps of the preparation of the 2, 5-hexanedione, the removal of front cut fraction, the refining of the 2, 5-hexanedione and so on. 2,5-dimethylfuran is taken as a raw material to synthesize the 2, 5-hexanedione, a step of adding water for atmospheric distillation after the removal of the front cut fraction is added during the synthesis, so the difficulty of the separation when a product is subjected to vacuum rectification is reduced, and the purity of the product is greatly improved; the front cut fraction and a transitional distillate can further be circularly used for the feeding during the post-synthesis so as to further improve the yield (can reach up to more than 90 percent), reduce the cost for the whole synthetic route, and has no pollution to the environment. The method has simple needed equipment, mild reaction conditions, and safe and easy operation, is suitable for industrialized production, is a more reasonable and more convenient novel way for circularly and economically synthesizing the 2, 5-hexanedione, and can prepare an intermediate, namely the 2, 5-hexanedione which is widely applied in fields such as medicine, spices, pesticides, photographic reagents, electroplating and paint-spraying.
Description
Technical field
The invention belongs to the synthetic field of organic cpds, relate to and a kind ofly have the preparation method of the compound of extensive use, specifically a kind of Synthetic 2, the method for 5-hexanedione in medicine, spices, sterilant, photograph medicament, plating field such as spray paint.
Background technology
2, the 5-hexanedione is a kind of important organic chemical industry's midbody, is widely used in medicine, spices, sterilant, photograph medicament, electroplates field such as spray paint.2, the compound method of 5-hexanedione is a lot, wherein have report with 2, the 5-dimethyl furan is following several kinds of comprising of raw material:
1. Shenk etc. adopts 2, and 5-dimethyl furan oxidation open loop obtains 3-alkene-2, the 5-hexanedione, and hydrogenating reduction gets 2 then, the 5-hexanedione, reaction scheme is following:
To control difficulty big for hydrogenation reaction in this method, and high to equipment requirements, the recycling of catalyzer has difficulties, and has increased the difficulty of suitability for industrialized production.
2. CA376066 has introduced and has adopted 2, the 5-dimethyl furan, and acid, distillation in 90-110 ℃ of dilute acid hydrolysis, neutralization reaction liquid, Synthetic 2, the method for 5-hexanedione, yield reaches more than 80%.
Though this method is easy, yield can use a large amount of acetic acid and catalyst sulfuric acid than higher in the reaction, and a large amount of sodium-acetates that produced behind the neutralization reaction liquid and a small amount of sodium sulfate can only be lost as waste, cause environmental pollution.
Summary of the invention
The technical issues that need to address of the present invention; Provide a kind of with 2; The 5-dimethyl furan is the raw material Synthetic 2, and the method for 5-hexanedione, building-up process have increased after removing front-end volatiles and add water air distillation step again; Isolating difficulty in the time of can reducing the rectification under vacuum product improves the product purity of building-up reactions.Further, be the recycle that feeds intake to improve yield, reduce and pollute if front-end volatiles are remake.
For solving the problems of the technologies described above, the technical scheme that the present invention adopted is:
A kind of Synthetic 2, the method for 5-hexanedione, carry out according to following sequence of steps:
A.2, the preparation of 5-hexanedione
With 2, the 5-dimethyl furan is a raw material, and in the presence of acetic acid, the dilute sulphuric acid catalytic hydrolysis gets reaction solution A;
B. front-end volatiles removes
Add sodium-acetate among the reaction solution A, air distillation removes front-end volatiles B;
React surplus liquid C and add water, normal pressure removes residue acetic acid, obtains transition distillate D and reaction residual solution E;
C.2, the 5-hexanedione is refining
Residual solution E underpressure distillation, cut are 2, the 5-hexanedione.
As optimization of the present invention, also comprise steps d in the above-mentioned compound method, promptly recycle: tell upper strata F and the G of lower floor after front-end volatiles B leaves standstill, its at the middle and upper levels F as 2, the use that feeds intake of 5-dimethyl furan raw material; The G of lower floor, transition distillate D in the later stage Synthetic 2, can be used as feeding intake of water and acetic acid in the 5-hexanedione process behind titration or gas chromatography determination acetic acid content;
After steps d is located at step b, all can in, the process forward and backward at step c.
As qualification of the present invention, in the above-mentioned compound method, step a carries out according to following step:
Getting feed ratio is 2 of 1000g: 400g: 480g: 24-36ml, and 5-dimethyl furan, Glacial acetic acid min. 99.5, water, 10% sulfuric acid mix, at 75-90 ℃ condition refluxed 36-50 hour, stopped reaction when material content is lower than 2%, cooling, reaction solution A.
Step b carries out according to following step:
With 2,5-dimethyl furan and sodium-acetate weight ratio are 1000: the ingredient proportion of 8-10, in reaction solution A, add sodium-acetate, and to stir 20-40 minute, air distillation removes 120 ℃ of front-end volatiles B;
React surplus liquid C and add water, normal pressure removes residue acetic acid, obtains transition distillate D and reaction residual solution E.
As preferred version of the present invention, Synthetic 2, the method for 5-hexanedione is to carry out according to following sequence of steps:
A.2, the preparation of 5-hexanedione
Getting feed ratio is 2 of 1000g: 400g: 480g: 24-36ml, and 5-dimethyl furan, Glacial acetic acid min. 99.5, water, 10% sulfuric acid mix, at 75-90 ℃ condition refluxed 36-50 hour, stopped reaction when material content is lower than 2%, cooling, reaction solution A;
B. front-end volatiles removes
With 2,5-dimethyl furan and sodium-acetate weight ratio are 1000: the ingredient proportion of 8-10, in reaction solution A, add sodium-acetate, and to stir 20-40 minute, air distillation removes 120 ℃ of front-end volatiles B;
React surplus liquid C and add water, normal pressure removes residue acetic acid, obtains transition distillate D and reaction residual solution E;
C.2, the 5-hexanedione is refining
Residual solution E underpressure distillation, cut are 2, the 5-hexanedione.
As preferred plan of the present invention, Synthetic 2, the method for 5-hexanedione may further comprise the steps:
A.2, the preparation of 5-hexanedione
Getting feed ratio is 1000g: 2 of 4 00g: 480g: 24-36ml, 5-dimethyl furan, Glacial acetic acid min. 99.5, water, 10% sulfuric acid mix, at 75-90 ℃ condition refluxed 36-50 hour, stopped reaction when material content is lower than 2%, cooling, reaction solution A;
B. front-end volatiles removes
With 2,5-dimethyl furan and sodium-acetate weight ratio are 1000: the ingredient proportion of 8-10, in reaction solution A, add sodium-acetate, and to stir 20-40 minute, air distillation removes 120 ℃ of front-end volatiles B;
React surplus liquid C and add water, normal pressure removes residue acetic acid, obtains transition distillate D and reaction residual solution E;
C.2, the 5-hexanedione is refining
Residual solution E underpressure distillation, cut are 2, the 5-hexanedione;
D. recycle
Tell upper strata F and the G of lower floor after front-end volatiles B leaves standstill, its at the middle and upper levels F as 2, the use that feeds intake of 5-dimethyl furan raw material; The G of lower floor, transition distillate D in the later stage Synthetic 2, can be used as feeding intake of water and acetic acid in the 5-hexanedione process behind titration or gas chromatography determination acetic acid content;
Wherein step a, b, c carry out in proper order, steps d be located at behind the step b and, process forward and backward at step c in all can.
The technique scheme that the present invention adopts; Compared with prior art, add water air distillation step again, can fill and separate impurities in the product because of removing to have increased behind the front-end volatiles; Isolating difficulty when having reduced the rectification under vacuum product improves the purity of title product greatly; Further, front-end volatiles and transition distillate are recycled in the feeding intake of later stage building-up process, yield improves (reaching as high as more than 90%) greatly, reduces the cost of whole synthesis path and environment is not produced and pollute; Adopt distillation method, conversion unit is simple, and reaction conditions is gentle, operational safety, easily, and having overcome needs that the hydrogenation synthesis method is existing to control the big drawback of difficulty, is fit to suitability for industrialized production.
To sum up, the technical progress that the present invention obtained is: Synthetic 2, and the method required equipment of 5-hexanedione is simple; Reaction conditions is gentle, operational safety is easy, product purity is high, yield is good, is fit to suitability for industrialized production, and can realizes that front-end volatiles and transition distillate recycle; It is a kind of recycling economy ground Synthetic 2 more easily more rationally; The new way of 5-hexanedione can prepare and be widely used in medicine, spices, sterilant, photograph medicament, electroplate the midbody 2 in fields such as spraying paint, 5-hexanedione.
The present invention below will combine Figure of description and specific embodiment to do further explain.
Description of drawings
Fig. 1 is an a step gained 2 in the embodiment of the invention 1, the color atlas of 5-hexanedione.
Embodiment
The following example only is used to explain the present invention, does not limit the present invention.
Embodiment 1
A kind of Synthetic 2, the method for 5-hexanedione, reaction scheme does
Carry out according to following sequence of steps:
A.2, the preparation of 5-hexanedione
Add raw material 2 in the four-hole bottle, 5-dimethyl furan 1000g, and add Glacial acetic acid min. 99.5 400g, water 480g, 10% sulfuric acid 30mL; Refluxed 48 hours at 82 ℃, sampling utilizes vapor-phase chromatography to detect and knows material content 1.5% (being lower than 2%) through ethyl acetate extraction; Cooling gets reaction solution A; Wherein the gas chromatographic detection condition is:
Chromatographic column: SE-30 capillary chromatographic column, 30m * 0.25mm * 0.25 μ m
Column temperature: 110 ℃/5min-＞20 ℃/min-＞260 ℃/5min;
Temperature of vaporization chamber: 260 ℃; Sensing chamber's temperature: 260 ℃;
Nebulizer gas pressure (N
2): 80kpa; Sample size: 0.2 μ L;
Quantivative approach: peak area normalization method; Splitting ratio: 100: 1
Color atlas is with reference to figure 1, wherein: the impurity in the 1.574-acetic acid; 1.633-acetic acid; 1.848-2, the 5-dimethyl furan; 2.727-2, the 5-hexanedione;
B. front-end volatiles removes
Add 9g sodium-acetate, stirring at room 30 minutes among the reaction solution A.Air distillation removes 110 ℃ of front-end volatiles B 421g;
In the surplus liquid C of reaction, add water 120g, continue air distillation and remove residue acetic acid, obtain transition distillate D 180g and reaction residual solution E.
D. recycle
After front-end volatiles B leaves standstill 24 hours, tell upper strata F promptly 2,5-dimethyl furan 10g is as the raw material use that feeds intake again; The G of lower floor, transition distillate D are through titration (carrying out according to GB/T 1628.3-2000 industry glacial acetic acid Determination on content volumetry); Record that the content of acetic acid is respectively 20%, 82% in them; The two all can be used as feeding intake of water and acetic acid in the later stage building-up process, realizes recycling.
C.2, the 5-hexanedione is refining
Above-mentioned residual solution E carries out underpressure distillation, collects 78-79 ℃/15mmHg cut 1011g, is 2, the 5-hexanedione, and the vapor-phase chromatography detection level is 98.8%, yield 86%.
Gas-chromatography detection method is with step a.
Embodiment 2
A kind of Synthetic 2, the method for 5-hexanedione, reaction scheme does
Carry out according to following sequence of steps:
A.2, the preparation of 5-hexanedione
Add raw material 2 in the four-hole bottle, 10% sulfuric acid of 5-dimethyl furan 990g, Glacial acetic acid min. 99.5 170g, water 120g, 30mL, and add embodiment 1 gained F 10g, G 411g (containing 82g acetic acid, 328g water) and 180g D (containing 148g acetic acid, 32g water); Refluxed 48 hours at 82 ℃; Ethyl acetate extraction is used in the sampling back, utilizes with embodiment 1 identical vapor-phase chromatography again and detects material content, and measured result is 1.7% (being lower than 2%); Cooling gets reaction solution A.
B. front-end volatiles removes
Add 9g sodium-acetate, stirring at room 30 minutes among the reaction solution A.Air distillation removes 110 ℃ of front-end volatiles B 410g, in the surplus liquid C of reaction, adds water 120g then, and the continuation air distillation removes residue acetic acid and obtains transition distillate D 176g.
C.2, the 5-hexanedione is refining
Above-mentioned residual solution E carries out underpressure distillation, collects 78-79 ℃/15mmHg cut 1059g, is 2, the 5-hexanedione, and the vapor-phase chromatography detection level is 98.5%, yield 90%.
D. recycle
Front-end volatiles B leaves standstill and tells upper strata F 10g after 24 hours, as the raw material use that can in the later stage building-up process, feed intake again; The G of lower floor, transition distillate D are through titration (carrying out according to GB/T 1628.3-2000 industry glacial acetic acid Determination on content volumetry); Record acetic acid content and be respectively 22%, 83%; The two all can be in the later stage building-up process as the feeding intake of water and acetic acid, realize reusing.
Embodiment 3-6
The difference of embodiment 3-6 and embodiment 1 is that the difference, reaction conditions of used amount is different, can be with reference to last table.Certainly, certainty different (not shown in the table) such as acetic acid content among material content, color atlas, product yield and the purity that causes recording before the cooling in the amount, step a of corresponding data such as reaction product because of above data difference, G and the D.
In their the compound method step, all the other contents are consistent.
Claims (6)
1. Synthetic 2, the method for 5-hexanedione is characterized in that said compound method carries out according to following sequence of steps:
A.2, the preparation of 5-hexanedione
With 2, the 5-dimethyl furan is a raw material, and in the presence of acetic acid, the dilute sulphuric acid catalytic hydrolysis gets reaction solution A;
B. front-end volatiles removes
Add sodium-acetate among the reaction solution A, air distillation removes front-end volatiles B;
React surplus liquid C and add water, normal pressure removes residue acetic acid, obtains transition distillate D and reaction residual solution E;
C.2, the 5-hexanedione is refining
Residual solution E underpressure distillation, cut are 2, the 5-hexanedione.
2. a kind of Synthetic 2 according to claim 1, the method for 5-hexanedione is characterized in that said compound method also comprises steps d, promptly
D. recycle
Tell upper strata F and the G of lower floor after front-end volatiles B leaves standstill, its at the middle and upper levels F as 2, the use that feeds intake of 5-dimethyl furan raw material; The G of lower floor, transition distillate D in the later stage Synthetic 2, can be used as feeding intake of water and acetic acid in the 5-hexanedione process behind titration or gas chromatography determination acetic acid content;
After steps d is located at step b, all can in, the process forward and backward at step c.
3. a kind of Synthetic 2 according to claim 1 and 2, the method for 5-hexanedione is characterized in that step a carries out according to following step:
Getting feed ratio is 2 of 1000g: 400g: 480g: 24-36ml, and 5-dimethyl furan, Glacial acetic acid min. 99.5, water, 10% sulfuric acid mix, at 75-90 ℃ condition refluxed 36-50 hour, stopped reaction when material content is lower than 2%, cooling, reaction solution A; Wherein, said 10% sulfuric acid is that mass ratio is 10% aqueous sulfuric acid; Said material content is lower than 2%, refers to this moment 2, and the content of 5-dimethyl furan is lower than 2% of material total amount this moment.
4. a kind of Synthetic 2 according to claim 1 and 2, the method for 5-hexanedione is characterized in that step b carries out according to following step:
With 2,5-dimethyl furan and sodium-acetate weight ratio are 1000: the ingredient proportion of 8-10, in reaction solution A, add sodium-acetate, and to stir 20-40 minute, air distillation removes 120 ℃ of front-end volatiles B;
React surplus liquid C and add water, normal pressure removes residue acetic acid, obtains transition distillate D and reaction residual solution E.
5. a kind of Synthetic 2 according to claim 1, the method for 5-hexanedione is characterized in that said compound method carries out according to following sequence of steps:
A.2, the preparation of 5-hexanedione
Getting feed ratio is 2 of 1000g: 400g: 480g: 24-36ml, and 5-dimethyl furan, Glacial acetic acid min. 99.5, water, 10% sulfuric acid mix, at 75-90 ℃ condition refluxed 36-50 hour, stopped reaction when material content is lower than 2%, cooling, reaction solution A; Wherein, said 10% sulfuric acid is that mass ratio is 10% aqueous sulfuric acid; Said material content is lower than 2%, refers to this moment 2, and the content of 5-dimethyl furan is lower than 2% of material total amount this moment;
B. front-end volatiles removes
With 2,5-dimethyl furan and sodium-acetate weight ratio are 1000: the ingredient proportion of 8-10, in reaction solution A, add sodium-acetate, and to stir 20-40 minute, air distillation removes 120 ℃ of front-end volatiles B;
React surplus liquid C and add water, air distillation removes residue acetic acid, obtains transition distillate D and reaction residual solution E;
C.2, the 5-hexanedione is refining
Residual solution E underpressure distillation, cut are 2, the 5-hexanedione.
6. a kind of Synthetic 2 according to claim 2, the method for 5-hexanedione is characterized in that said compound method may further comprise the steps:
A.2, the preparation of 5-hexanedione
Getting feed ratio is 2 of 1000g: 400g: 480g: 24-36ml, and 5-dimethyl furan, Glacial acetic acid min. 99.5, water, 10% sulfuric acid mix, at 75-90 ℃ condition refluxed 36-50 hour, stopped reaction when material content is lower than 2%, cooling, reaction solution A; Wherein, said 10% sulfuric acid is that mass ratio is 10% aqueous sulfuric acid; Said material content is lower than 2%, refers to this moment 2, and the content of 5-dimethyl furan is lower than 2% of material total amount this moment;
B. front-end volatiles removes
With 2,5-dimethyl furan and sodium-acetate weight ratio are 1000: the ingredient proportion of 8-10, in reaction solution A, add sodium-acetate, and to stir 20-40 minute, air distillation removes 120 ℃ of front-end volatiles B;
React surplus liquid C and add water, air distillation removes residue acetic acid, obtains transition distillate D and reaction residual solution E;
C.2, the 5-hexanedione is refining
Residual solution E underpressure distillation, cut are 2, the 5-hexanedione;
D. recycle
Tell upper strata F and the G of lower floor after front-end volatiles B leaves standstill, its at the middle and upper levels F as 2, the use that feeds intake of 5-dimethyl furan raw material; The G of lower floor, transition distillate D in the later stage Synthetic 2, can be used as feeding intake of water and acetic acid in the 5-hexanedione process behind titration or gas chromatography determination acetic acid content;
Wherein step a, b, c carry out in proper order, and steps d is located at behind the step b and all can in the forward and backward or process at step c.
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| CN2008100797668A CN101423467B (en) | 2008-11-14 | 2008-11-14 | Method for synthesizing 2,5-acetonyl acetone |
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|---|---|---|---|
| CN2008100797668A CN101423467B (en) | 2008-11-14 | 2008-11-14 | Method for synthesizing 2,5-acetonyl acetone |
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| CN101423467A CN101423467A (en) | 2009-05-06 |
| CN101423467B true CN101423467B (en) | 2012-03-07 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022242730A1 (en) | 2021-05-21 | 2022-11-24 | 中国石油化工股份有限公司 | Method for preparing 2, 5-hexanedione by catalyzing and converting biomass by one-pot synthesis |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106536470A (en) * | 2014-02-28 | 2017-03-22 | 罗地亚经营管理公司 | Synthesis of diketone compounds from carbohydrates |
| CN105348056B (en) * | 2015-12-11 | 2017-08-25 | 中国科学院山西煤炭化学研究所 | A kind of method that two phase process synthesizes 2,5 acetyl butyryls |
| CN105439836B (en) * | 2015-12-11 | 2017-07-25 | 中国科学院山西煤炭化学研究所 | A kind of method that solid acid catalysis prepares 2,5 acetyl butyryls |
| US11608317B2 (en) | 2021-03-16 | 2023-03-21 | Chevron Phillips Chemical Company, Lp | Two-step synthesis of pyrrole compounds from furan compounds |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA376066A (en) * | 1938-08-30 | J. Toussaint Walter | Acetonylacetone |
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2008
- 2008-11-14 CN CN2008100797668A patent/CN101423467B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA376066A (en) * | 1938-08-30 | J. Toussaint Walter | Acetonylacetone |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022242730A1 (en) | 2021-05-21 | 2022-11-24 | 中国石油化工股份有限公司 | Method for preparing 2, 5-hexanedione by catalyzing and converting biomass by one-pot synthesis |
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