CN116751145A - A method for preparing 6-ethylthio-3-hepten-2-one - Google Patents
A method for preparing 6-ethylthio-3-hepten-2-one Download PDFInfo
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- CN116751145A CN116751145A CN202310422089.XA CN202310422089A CN116751145A CN 116751145 A CN116751145 A CN 116751145A CN 202310422089 A CN202310422089 A CN 202310422089A CN 116751145 A CN116751145 A CN 116751145A
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- C07—ORGANIC CHEMISTRY
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- C07C319/00—Preparation of thiols, sulfides, hydropolysulfides or polysulfides
- C07C319/14—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides
- C07C319/20—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides by reactions not involving the formation of sulfide groups
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Abstract
本发明涉及化学合成技术领域，尤其涉及IPC C07C323，更具体的涉及，一种制备6‑乙硫基‑3‑庚烯‑2‑酮的方法。本发明通过将3‑乙硫基丁醛，水、催化剂混合，在25～35℃滴加双乙烯酮，保温反应7～10h后，加酸脱水，反应结束后碱洗，真空脱溶得到6‑乙硫基‑3‑庚烯‑2‑酮。本发明以3‑乙硫基丁醛，双乙烯酮、催化剂、水为原料，能耗少，不会产生含醋酸钠、甲醇和丙酮等物质废水。The present invention relates to the field of chemical synthesis technology, in particular to IPC C07C323, and more specifically to a method for preparing 6-ethylthio-3-hepten-2-one. In the present invention, 3-ethylthiobutyraldehyde, water and catalyst are mixed, diketene is added dropwise at 25-35°C, and after a heat preservation reaction of 7-10 hours, acid is added for dehydration. After the reaction is completed, 6-ethylthiobutyraldehyde is washed with alkali and vacuum desolvated to obtain 6-ethylbutyraldehyde. Thio-3-hepten-2-one. The invention uses 3-ethylthiobutyraldehyde, diketene, catalyst and water as raw materials, consumes less energy and does not produce wastewater containing sodium acetate, methanol, acetone and other substances.
Description
Technical Field
The invention relates to the technical field of chemical synthesis, in particular to IPC C07C323, and more particularly relates to a method for preparing 6-ethylthio-3-hepten-2-one.
Background
Clethodim can be used as a novel herbicide after seedling in dry farmland, can prevent and kill annual and perennial grassy weeds, and has excellent selectivity. 6-ethylthio-3-hepten-2-one is often used as an important pesticide and pharmaceutical intermediate for the synthesis of cyclohexenone herbicides.
In the traditional method, 6-ethylthio-3-heptylene-2-ketone is synthesized, sodium acetoacetate aqueous solution and toluene are mixed, then acetic acid is used for regulating the pH value, finally 3-ethylthio-butyraldehyde is dripped, the reaction is carried out under heat preservation, water washing and desolventizing are carried out to obtain 6-ethylthio-3-heptylene-2-ketone, sodium acetoacetate is unstable, the sodium acetoacetate is prepared by reacting methyl acetoacetate or ethyl acetoacetate with liquid alkali when in use, a large amount of wastewater containing substances such as sodium acetate, methanol and acetone can be generated, the wastewater can not be directly subjected to biochemical treatment, and a series of treatments are needed, so that the energy consumption is high, and dangerous wastes such as sodium acetate trihydrate can be generated. Therefore, the problems that sodium acetoacetate is required to be prepared for preparing heptenone, the energy consumption is high, the wastewater composition is complex, and the treatment difficulty is high exist at present.
The prior patent CN202211058649.X discloses a preparation method and a composition of acetoacetic acid, 6-ethylthio-3-hepten-2-one and intermediates thereof, the method has the advantages of simple operation, mild reaction conditions, high atom utilization rate, high overall yield and better purity, but the method uses a hydration catalyst, and a catalyst selected from specific palladium, nickel or rhodium is high in cost.
Disclosure of Invention
In order to solve the problems in the prior art, a first aspect of the present invention provides a method for preparing 6-ethylsulfanyl-3-hepten-2-one, which comprises:
toluene, 3-ethylthio butyraldehyde, water and a catalyst are added into a four-neck flask, mixed, and then diketene is added dropwise at the temperature of 25-35 ℃, after the reaction is carried out for 7-10 hours, acid is added for dehydration, and after the reaction is finished, alkali washing and vacuum desolventizing are carried out, thus obtaining the 6-ethylthio-3-hepten-2-one.
The reaction equation of the present invention is as follows:
preferably, the reaction mole ratio of the 3-ethylthiobutyraldehyde to the diketene is 1: (1.05-1.10); further preferred is 1:1.05.
preferably, the mass ratio of the water to the diketene is (22-25): 100; more preferably, (22 to 23): 100.
in a preferred embodiment, the mass ratio of water to diketene is 22.65:100.
preferably, the catalyst is an organic basic catalyst.
Preferably, the organic basic catalyst comprises one or more of triethylamine, piperidine, 4-dimethylaminopyridine, pyridine and diisopropylethylamine; further preferred are triethylamine, piperidine, 4-dimethylaminopyridine or pyridine.
Preferably, the mass ratio of the catalyst to the diketene is (0.5-10): 100; further preferably, (0.5 to 3): 100.
in a preferred embodiment, the mass ratio of catalyst to diketene is 1:100.
preferably, the temperature of the heat preservation reaction is 30-110 ℃; further preferred is 30, 70 or 110 ℃.
Preferably, the acid is sulfuric acid or phosphoric acid.
Preferably, the sulfuric acid is a 95-98 wt% sulfuric acid aqueous solution; further preferred is 98wt% aqueous sulfuric acid.
Preferably, the mass ratio of the acid to the diketene is 0.004-0.015: 1
Preferably, the solution used for the alkaline washing is an alkaline solution.
Preferably, the alkaline solution is one or more of sodium hydroxide aqueous solution, sodium carbonate aqueous solution, sodium bicarbonate aqueous solution and potassium hydroxide aqueous solution; further preferred is an aqueous sodium hydroxide solution, an aqueous sodium carbonate solution or an aqueous sodium bicarbonate solution.
Preferably, the mass concentration of the solute of the alkaline solution is 0.1% -0.2%.
Preferably, the alkaline washing temperature is 30-50 ℃.
Preferably, the vacuum desolventizing pressure is-0.095 to-0.098 MPa.
Preferably, the vacuum desolventizing temperature is 55-75 ℃.
Preferably, the 3-ethylsulfatobutyraldehyde CAS number is 27205-24-9.
Preferably, the diketene CAS number is 674-82-8.
According to the invention, diketene is selected to replace sodium acetoacetate prepared from methyl acetoacetate or ethyl acetoacetate and liquid alkali, so that solid waste can be reduced, energy consumption can be reduced, the generation of harmful substances can be reduced, and the yield can be improved. The inventor unexpectedly found that diketene is added in the process of preparing 6-ethylthio-3-hepten-2-one, so that the on-site preparation of sodium acetoacetate, which is unstable, is avoided, is prepared by reacting methyl acetoacetate or ethyl acetoacetate with liquid alkali, and can generate a large amount of substance wastewater containing sodium acetate, methanol, acetone and the like, and the wastewater treatment needs to consume a large amount of energy, and can also generate dangerous wastes such as sodium acetate trihydrate and the like. The diketene and the 3-ethylthio butyraldehyde are selected to react under the action of water and a catalyst, so that the subsequent wastewater treatment is avoided. On the other hand, the sodium acetoacetate is selected, the pH value needs to be regulated by acetic acid in the experimental process, the operation is more complicated, more intermediate products possibly cause the subsequent yield reduction, the subsequent yield reduction is replaced by the diketene, and only the diketene is required to be weighed, so that the operation steps are simplified, the generation of excessive intermediate products is avoided, and the yield is improved. In addition, sodium acetoacetate is prepared by reacting methyl acetoacetate or ethyl acetoacetate with liquid alkali, then the pH value is adjusted, and the sodium acetoacetate reacts with 3-ethylthio-butyraldehyde, so that water washing is needed in the post-treatment process, and the scheme of the invention is used.
In the invention, the mass ratio of water to diketene is controlled to be (22-25): 100, the yield of the product can be improved. The inventor unexpectedly found that by controlling the mass ratio of water to diketene, adding toluene, 3-ethylthio butyraldehyde, mixing water and a catalyst, dropwise adding diketene at 25-35 ℃, and reacting for 7-10 hours under heat preservation, the 6-ethylthio-3-hepten-2-one with high purity and high yield can be obtained without a metal catalyst, the production cost is reduced, the steps are simplified, and the yield is improved. And controlling the mass ratio of water to diketene, and synthesizing a large amount of 6-ethylthio-4-hydroxy-2-ketone before dehydration reaction.
Advantageous effects
1. According to the invention, diketene is selected to replace sodium acetoacetate prepared from methyl acetoacetate or ethyl acetoacetate and liquid alkali, so that solid waste can be reduced, energy consumption can be reduced, the generation of harmful substances can be reduced, and the yield can be improved. In the invention, diketene and water can undergo a weak reversible reaction to generate acetoacetic acid, the acetoacetic acid can undergo an irreversible reaction with thioether aldehyde under the action of a catalyst, the continuous progress of the post-reaction can promote the continuous progress of the pre-reaction, and finally the reaction is completed thoroughly.
2. In the invention, specific organic alkaline catalysts such as triethylamine, piperidine, 4-dimethylaminopyridine and pyridine are adopted, and the mass ratio of the catalyst to the diketene is controlled to be (0.5-3): 100, the reaction speed can be increased, the yield of the intermediate 6-ethylthio-4-hydroxy-2-ketone can be increased even if a metal catalyst is not used in the reaction process, the high-yield 6-ethylthio-3-hepten-2-ketone can be obtained after dehydration reaction, and the yield of the product is increased. Meanwhile, the organic alkaline catalyst has good effect, can be recycled, and reduces the cost. In the system, if an inorganic alkaline catalyst is used, the mixing of acetic acid is also required, so that sodium acetate wastewater is easy to form, and the industrial production is not facilitated. In addition, the invention adopts the organic alkaline catalyst, so that no metal element is generated in the wastewater, and the wastewater can be subjected to biochemical treatment.
3. In the invention, the mass ratio of water to diketene is controlled to be (22-25): 100, the yield of the product can be improved.
4. According to the invention, diketene is adopted to replace sodium acetoacetate, 3-ethylthio-butyraldehyde reacts under the action of water and a catalyst, the temperature of the thermal insulation reaction is controlled to be 30-110 ℃, the reaction time is controlled to be 7-10 h, the maximum reaction of raw materials is ensured, the loss of the raw materials is reduced, alkaline solution is adopted to perform alkaline washing after the reaction is finished, the alkaline washing temperature and the concentration range of solute in the alkaline solution are controlled, so that impurities are dissolved in water phase, 6-ethylthio-3-hepten-2-one is dissolved in toluene phase, thus the 6-ethylthio-3-hepten-2-one is separated and purified, the operation steps are simplified, and the vacuum desolventizing temperature is set to be 55-75 ℃ and the pressure is set to be-0.095 to-0.098 MPa, so that a large amount of 6-ethylthio-3-hepten-2-one can be obtained with less loss.
5. In the invention, toluene, 3-ethylthio butyraldehyde, water and a catalyst are directly added, and diketene is added dropwise at 25-35 ℃ for heat preservation reaction, so that step reaction is not needed, and the reaction flow is simplified. Meanwhile, the mass ratio of water to diketene and the mass ratio of the catalyst to diketene are directly controlled, the yield of an intermediate product 6-ethylthio-4-hydroxy-2-ketone is improved, the yield and purity of a final product are further controlled, the use of a metal catalyst is not needed, and the cost is reduced.
Detailed Description
Example 1
Into a 250mL four-necked flask, 50mL of toluene, 13.22g of 3-ethylsulfanyl butyraldehyde, 2.00g of water and 0.10g of piperidine are added, 8.83g of diketene is dropwise added at 30 ℃, the temperature is kept at 30 ℃ for 10 hours, then 0.045g of 98% wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 20g of sodium hydroxide aqueous solution with the mass fraction of 0.1% of sodium hydroxide is added at 30 ℃, stirring and standing are carried out, the lower wastewater is separated, the toluene phase is desolventized to 75 ℃ under-0.095 MPa, and the 6-ethylsulfanyl-3-hepten-2-one is obtained.
Example 2
50mL of toluene, 13.22g of 3-ethylsulfanyl butyraldehyde, 2.00g of water and 0.10g of piperidine are added into a 250mL four-necked flask, 8.83g of diketene is added dropwise at 30 ℃, the temperature is kept for 7 hours at 30 ℃, then 0.045g of 98% wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 20g of sodium hydroxide aqueous solution with the mass fraction of 0.1% of sodium hydroxide is added at 30 ℃, stirring and standing are carried out, the lower wastewater is separated, the toluene phase is desolventized to 55 ℃ at-0.098 MPa, and the 6-ethylsulfanyl-3-hepten-2-one is obtained.
Example 3
50mL of toluene, 13.22g of 3-ethylsulfanyl butyraldehyde, 2.00g of water and 0.10g of piperidine are added into a 250mL four-necked flask, 8.83g of diketene is added dropwise at 30 ℃, the temperature is kept at 70 ℃ for 10 hours, then 0.045g of 98% wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 20g of sodium hydroxide aqueous solution with the mass fraction of 0.1% of sodium hydroxide is added at 50 ℃, stirring and standing are carried out, the lower wastewater is separated, and the toluene phase is desolventized to 65 ℃ under-0.097 MPa, so as to obtain 6-ethylsulfanyl-3-hepten-2-one.
Example 4
50mL of toluene, 13.22g of 3-ethylsulfanyl butyraldehyde, 2.00g of water and 0.10g of piperidine are added into a 250mL four-necked flask, 8.83g of diketene is added dropwise at 30 ℃, the temperature is kept at 70 ℃ for 7 hours, then 0.045g of 98% wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 10g of sodium hydroxide aqueous solution with the mass fraction of 0.2% of sodium hydroxide is added at 40 ℃, stirring and standing are carried out, the lower wastewater is separated, and the toluene phase is desolventized to 65 ℃ at-0.097 MPa, so as to obtain 6-ethylsulfanyl-3-hepten-2-one.
Example 5
50mL of toluene, 13.22g of 3-ethylthio butyraldehyde, 2.00g of water and 0.10g of piperidine are added into a 250mL four-neck flask, 8.83g of diketene is dropwise added at 30 ℃, the temperature is kept at 110 ℃ for 7 hours, then 0.045g of 98% wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 10g of sodium carbonate aqueous solution with the mass fraction of 0.2% of sodium carbonate is added at 40 ℃, stirring and standing are carried out, the lower wastewater is separated, the toluene phase is desolventized to 65 ℃ at-0.097 MPa, and the 6-ethylthio-3-hepten-2-one is obtained.
Example 6
50mL of toluene, 13.22g of 3-ethylsulfanyl butyraldehyde, 2.00g of water and 0.20g of piperidine are added into a 250mL four-necked flask, 8.83g of diketene is dropwise added at 30 ℃, the temperature is kept for 10 hours at 30 ℃, then 0.090g of 98% wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 10g of sodium carbonate aqueous solution with the mass fraction of 0.2% of sodium carbonate is added at 40 ℃, the mixture is stirred and left stand, the lower wastewater is separated, and the toluene phase is desolventized to 65 ℃ at-0.097 MPa, so as to obtain 6-ethylsulfanyl-3-hepten-2-one.
Example 7
50mL of toluene, 13.22g of 3-ethylsulfanyl butyraldehyde, 2.00g of water and 0.05g of 4-dimethylaminopyridine are added into a 250mL four-neck flask, 8.83g of diketene is dropwise added at 30 ℃, the temperature is kept for 10 hours, then 0.045g of 98wt% sulfuric acid aqueous solution is added for dehydration, after the reaction is finished, 10g of sodium carbonate aqueous solution with the mass fraction of 0.2% of sodium carbonate is added at 40 ℃, stirring and standing are carried out, the lower wastewater is separated, and toluene phase is desolventized to 65 ℃ under-0.097 MPa, so as to obtain 6-ethylsulfanyl-3-hepten-2-one.
Comparative example 1
The embodiment of comparative example 1 is the same as in example 1, except that the catalyst is 11.5wt% aqueous sodium hydroxide.
Comparative example 2
The embodiment of comparative example 2 is the same as example 1, except that the process is catalyst-free.
Comparative example 3
The embodiment of comparative example 3 is the same as in example 1, except that 0.69g of potassium tetrachloropalladate is also added to the protocol.
Comparative example 4
The embodiment of comparative example 4 is the same as in example 1, except that the mass ratio of water to diketene is 78:100.
comparative example 5
The embodiment of comparative example 5 is the same as in example 1, except that the mass ratio of catalyst to diketene is 10:100.
performance testing
1. The 6-ethylsulfanyl-3-hepten-2-one obtained in examples 1 to 5 was weighed by a weighing balance, and the results were recorded in Table 1.
2. The purity of the 6-ethylsulfanyl-3-hepten-2-one obtained in examples 1 to 5 was measured by HPLC, and Table 1 was recorded.
3. Calculated yield = (mass purity)/theoretical mass.
TABLE 1
| Quality of | Purity of | Yield is good | |
| Example 1 | 17.2g | 95％ | 95％ |
| Example 2 | 17.4g | 93％ | 94％ |
| Example 3 | 17.4g | 94％ | 95％ |
| Example 4 | 17.4g | 93％ | 94％ |
| Example 5 | 17.3g | 94％ | 94％ |
| Example 6 | 17.4g | 93％ | 94％ |
| Example 7 | 17.4g | 93％ | 94％ |
| Comparative example 1 | 21.2 | 0.8％ | 1％ |
| Comparative example 2 | 21.2 | 0.8％ | 1％ |
| Comparative example 3 | 21.2 | 94％ | 95％ |
| Comparative example 4 | 19.1 | 45％ | 50％ |
| Comparative example 5 | 17.6 | 93％ | 95％ |
Claims (10)
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| CN202310422089.XA CN116751145B (en) | 2023-04-19 | A method for preparing 6-ethylthio-3-hepten-2-one |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6300281B1 (en) * | 2000-07-03 | 2001-10-09 | Valent U.S.A. Corporation | Optically pure(−) clethodim, compositions and methods for controlling plant growth comprising the same |
| CN108239057A (en) * | 2017-12-31 | 2018-07-03 | 成都波洛克科技有限公司 | Organic synthesis intermediate α, the production method of γ-dehydroacetic acid |
| CN115286500A (en) * | 2022-08-31 | 2022-11-04 | 山东新和成氨基酸有限公司 | A kind of preparation method and composition of acetoacetic acid, 6-ethylthio-3-hepten-2-one and intermediate thereof |
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6300281B1 (en) * | 2000-07-03 | 2001-10-09 | Valent U.S.A. Corporation | Optically pure(−) clethodim, compositions and methods for controlling plant growth comprising the same |
| CN108239057A (en) * | 2017-12-31 | 2018-07-03 | 成都波洛克科技有限公司 | Organic synthesis intermediate α, the production method of γ-dehydroacetic acid |
| CN115286500A (en) * | 2022-08-31 | 2022-11-04 | 山东新和成氨基酸有限公司 | A kind of preparation method and composition of acetoacetic acid, 6-ethylthio-3-hepten-2-one and intermediate thereof |
Non-Patent Citations (3)
| Title |
|---|
| J.M.BRIODY 等: "Acylation. Part XVI. The Spontaneous and Catalysed Hydrolysis of Diketen", JOURNAL OF THE CHEMICAL SOCIETY, 1 January 1965 (1965-01-01), pages 3778 - 3785 * |
| RAFAEL GO´MEZ-BOMBARELLI 等: "Kinetic study of the neutral and base hydrolysis of diketene", J. PHYS. ORG. CHEM., vol. 22, 8 December 2008 (2008-12-08), pages 438 - 442 * |
| RAFAEL GÓMEZ-BOMBARELLI 等: "Mechanisms of Lactone Hydrolysis in Neutral and Alkaline Conditions", THE JOURNAL OF ORGANIC CHEMISTRY, vol. 78, 11 June 2013 (2013-06-11), pages 6868 - 6879, XP002756931, DOI: 10.1021/jo400258w * |
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