CN114213231A - Synthesis process of 1-phenyl-2-butanone - Google Patents
Synthesis process of 1-phenyl-2-butanone Download PDFInfo
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- CN114213231A CN114213231A CN202111622704.9A CN202111622704A CN114213231A CN 114213231 A CN114213231 A CN 114213231A CN 202111622704 A CN202111622704 A CN 202111622704A CN 114213231 A CN114213231 A CN 114213231A
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- C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
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Abstract
The invention discloses a method for synthesizing 1-phenyl-2-butanone, which comprises the following steps: adding sodium methoxide in dimethylbenzene in batches, and then beginning to dropwise add phenylacetonitrile; cooling the reaction liquid, dropping ethyl propionate, heating and refluxing for reaction and ripening; after the reaction is finished, adding the reaction solution into ice water, extracting impurities by toluene, adjusting the pH value by hydrochloric acid, and performing reaction post-treatment such as suction filtration, suspension washing, drying and the like to obtain an intermediate; adding the intermediate into a sulfuric acid solution, heating and curing, pouring the reaction solution into crushed ice, adding toluene for multiple times of extraction, combining upper organic phases, washing, drying, performing suction filtration and concentration sequentially on a saturated sodium bicarbonate solution, water, a sodium chloride solution and the like to obtain a crude product; and carrying out reduced pressure distillation on the crude product, and collecting product fractions. The GC purity of the high-purity 1-phenyl-2-butanone prepared by the invention can reach more than 99.5 percent, and the total yield is more than 95 percent.
Description
Technical Field
The invention relates to a process method for synthesizing 1-phenyl-2-butanone, belonging to the technical field of synthesis of development and application of organic medical intermediates.
Background
1-phenyl-2-butanone is an important organic chemical raw material, is commonly used in natural products, active alkaloids, medicaments and agricultural preparations, and belongs to an important organic medicine synthetic intermediate. Research reports of related synthesis methods at home and abroad are more, but the synthesis method with industrial application value mainly comprises a phenylacetic acid method, high-temperature catalytic reaction is needed, the defects of high equipment requirement, high cost, high danger, low product conversion rate and the like exist, and the method is not suitable for industrial production.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method for synthesizing the 1-phenyl-2-butanone has the advantages of easily available and cheap raw materials, low cost, high product conversion rate, simple operation, no harsh reaction requirements and easy industrialization, and is the most economical and applicable process method for synthesizing the 1-phenyl-2-butanone.
In order to solve the above problems, the present invention provides a method for synthesizing 1-phenyl-2-butanone, which is characterized by comprising the following steps:
step 1): adding sodium methoxide in batches at 20-25 ℃ by using dimethylbenzene as a solvent, dropwise adding phenylacetonitrile after the sodium methoxide is added, and stirring after the phenylacetonitrile is dropwise added;
step 2): placing the reaction liquid obtained in the step 1) in an ice water bath, cooling to 0-10 ℃, starting to dropwise add ethyl propionate, withdrawing the ice water bath after dropwise adding, recovering to room temperature, then heating and refluxing, and controlling the temperature in the reaction liquid to be 105-110 ℃ for reaction and ripening;
step 3): adding the reaction liquid obtained in the step 2) into water, and standing and layering after reaction quenching; removing the organic phase on the upper layer, continuously extracting impurities from the water phase on the lower layer by using methylbenzene, and keeping a water layer; adjusting the pH value of the water phase to 1-2 by using concentrated hydrochloric acid to generate a solid, cooling to 0-5 ℃, standing, performing suction filtration on a filter cake after 2 times of suspension washing by using water, and performing air supply drying on the obtained solid at 50 ℃ for 24 hours to obtain an intermediate;
step 4): adding the intermediate obtained in the step 3) into a sulfuric acid solution, heating after adding, maintaining the temperature in the reaction at 130-140 ℃, and reacting and ripening;
step 5): adding the reaction liquid obtained in the step 4) into crushed ice, carrying out reaction quenching, then extracting with toluene, combining organic phases, washing with a saturated sodium bicarbonate solution, water and a sodium chloride solution in sequence, drying with magnesium sulfate, and then concentrating to obtain a crude concentrated solution; and (4) carrying out reduced pressure distillation on the crude product, and collecting 117-118 ℃/26mmHg fractions.
Preferably, the step 1) is specifically: adding dimethylbenzene into a container, adding sodium methoxide in batches while stirring at the temperature of 20-25 ℃, adding the sodium methoxide in three times, starting to dropwise add phenylacetonitrile after the addition is finished, and stirring for 0.5h after the dropwise addition is finished; the weight ratio of the volume of the xylene to the phenylacetonitrile is 13-15L/kg, and the molar ratio of the sodium methoxide to the phenylacetonitrile is (2-3): 1.
preferably, the step 2) is specifically: cooling the reaction liquid obtained in the step 1) to 0-10 ℃, dropwise adding ethyl propionate, withdrawing an ice water bath after dropwise adding, recovering to room temperature, heating and refluxing, and controlling the temperature in the reaction liquid to be 105-110 ℃ for reaction for 3h and ripening; the molar ratio of the ethyl propionate to the phenylacetonitrile is (2.5-3): 1.
preferably, the step 3) is specifically: slowly adding the reaction solution obtained in the step 2) into water, and standing and layering after quenching reaction; removing the organic phase on the upper layer, continuously extracting impurities from the water phase on the lower layer by using methylbenzene, and keeping a water layer; adjusting the pH value of the water phase to 1-2 by using concentrated hydrochloric acid, generating a large amount of solid, cooling to 0-5 ℃, standing for 3h, carrying out suction filtration, carrying out suspension washing on a filter cake for 2 times by using water, carrying out suction filtration, and carrying out air supply drying on the obtained solid at 50 ℃ for 24h to obtain an intermediate; wherein, the ratio of the toluene volume required by extracting impurities to the reaction liquid volume is 0.5: 1, 2 extractions are required.
Preferably, the step 4) is specifically: slowly adding the intermediate obtained in the step 3) into a sulfuric acid solution with the mass concentration of 65%, heating after adding, and keeping the reaction temperature at 130-140 ℃ for reaction for 5 hours to mature; the weight ratio of the volume required by the sulfuric acid to the intermediate is 1.5-2L/kg.
Preferably, the step 5) is specifically: slowly adding the reaction liquid obtained in the step 4) into crushed ice, extracting with toluene after reaction quenching, combining organic phases, washing with saturated sodium bicarbonate solution, water and sodium chloride solution in sequence, drying with magnesium sulfate, and concentrating to obtain a crude concentrated solution; and (3) carrying out reduced pressure distillation on the crude product, collecting 117-118 ℃/26mmHg fractions, and sending the fractions to GC for detection, wherein the purity reaches 99.5%.
The invention adopts industrial cheap and easily obtained benzyl cyanide and ethyl propionate as main raw materials and common auxiliary materials such as sodium methoxide, xylene, toluene and the like, and the crude product of the target product is obtained by 2-step synthesis, and the 1-phenyl-2-butanone product with high purity is obtained after reduced pressure distillation and purification, wherein the GC purity is more than 99.5 percent, and the total yield is more than 95 percent. The method has the advantages of low cost of synthetic raw materials, simple process, good reaction controllability, high reaction conversion rate and the like, and is suitable for industrial production.
Compared with the prior art, the invention has the following beneficial effects:
1. the raw materials of benzyl cyanide, ethyl propionate, concentrated sulfuric acid, concentrated hydrochloric acid, xylene, toluene, sodium methoxide and the like required by synthesis are cheap, easily available and industrialized products, and the synthesis process has mild reaction conditions and convenient operation; the reaction is easy to control, the side reaction is less, and the reaction conversion rate is high; the target product is simple to purify, and the whole process is suitable for industrial production.
2. The invention adopts 2 steps to synthesize the 1-phenyl-2-butanone. The method comprises the following steps of reacting phenylacetonitrile with ethyl propionate, reducing the occurrence of side reactions and improving the conversion rate by controlling the reaction temperature and the dosage ratio of materials to synthesize an intermediate, reacting with 65% sulfuric acid solution to remove cyano groups, distilling the obtained crude product under reduced pressure, and purifying to obtain the high-purity 1-phenyl-2-butanone, wherein the GC purity is over 99.5%, and the total yield is over 95%.
Detailed Description
In order to make the invention more comprehensible, preferred embodiments are described in detail below.
Examples 1 and 2 provide a method for synthesizing 1-phenyl-2-butanone. The chemical equation of the synthesis process is as follows:
example 1
A method for synthesizing 1-phenyl-2-butanone comprises the following steps:
(1) preparing a 10L glass reaction kettle, adding 4.5L dimethylbenzene at the temperature of 20-25 ℃, stirring, slowly adding sodium methoxide (313.4g, 5.8mol) in batches, and adding the sodium methoxide in 3 times; after the addition, the phenylacetonitrile (340g, 2.9mol) is slowly dripped, and the mixture is stirred for 30min after the dripping is finished;
(2) cooling the reaction liquid to 0-10 ℃ by adopting an ice water bath, starting to dropwise add ethyl propionate (740.4g, 7.25mol), withdrawing the ice water bath after dropwise adding, recovering to room temperature, then heating and refluxing, and controlling the temperature in the reaction liquid to be 105-110 ℃ for reaction for 3h and ripening;
(3) preparing a 20L reaction extraction device, adding 4.5L of tap water, slowly adding the reaction solution while stirring, standing for layering after dissolution and clarification, discarding the upper organic phase, extracting impurities from the lower aqueous phase by using toluene (3L multiplied by 2), adjusting the pH value of the obtained aqueous phase to 1 by using concentrated hydrochloric acid (600ml), cooling to 0-5 ℃, standing for 3 hours, performing suction filtration, performing suspension filtration on a filter cake by using pure water (2L multiplied by 2) to obtain 810g of wet solid, and finally performing air supply drying at 50 ℃ for 24 hours to obtain 495g of a dry intermediate;
(4) preparing a 2L glass reaction bottle, adding 750ml of prepared sulfuric acid solution with the mass concentration of 65%, adding 495g of intermediate a little by little, stirring for dissolving, starting heating and raising the temperature, controlling the temperature at 130-140 ℃, and reacting for 5 hours for ripening;
(5) after the reaction is finished, the reaction solution is returned to the room temperature, then the reaction solution is slowly poured into 1kg of crushed ice and 1L of water, stirred, added with toluene (1L multiplied by 3) for extraction, the organic phase toluene is combined, washed by saturated sodium bicarbonate solution (1.5L multiplied by 1), pure water (1.5L multiplied by 1) and saturated sodium chloride solution (1.5L multiplied by 2) in sequence, dried by 100g of magnesium sulfate, filtered by suction and concentrated to obtain 480g of crude product;
adding 480g of the crude product into a 1L distillation flask, heating by using an electric heating jacket, performing plus-minus distillation by using a 10cm thorn-shaped distillation column, and collecting a fraction with bp of 117-118 ℃/26mmHg to obtain 408g of the compound.
The nuclear magnetic resonance processing data, GC, specific gravity and refractive index of the prepared compound are detected as follows:
1H-NMR(CDCl3，400MHz，δppm)：δ＝7.30～7.34(2H，m)，7.26(1H，m)，7.19～7.21(2H，m)，3.68(2H，s)，2.44～2.49(2H，m)，1.00～1.04(3H，m)ppm
GC：99.5％
d20/20：0.9886
n20/D：1.5118
from the above data, it can be seen that the compound obtained above is 1-phenyl-2-butanone with a total yield of 95%.
Example 2
A method for synthesizing 1-phenyl-2-butanone comprises the following steps:
(1) preparing a 10L glass reaction kettle, adding 5.1L dimethylbenzene at the temperature of 20-25 ℃, stirring, slowly adding sodium methoxide (470.1g, 8.7mol) in batches, and adding in 3 times; after the addition, the phenylacetonitrile (340g, 2.9mol) is slowly dripped, and the mixture is stirred for 30min after the dripping is finished;
(2) cooling the reaction liquid to 0-10 ℃ by adopting an ice water bath, starting to dropwise add ethyl propionate (888.5g, 8.7mol), removing the ice water bath after dropwise adding, recovering to room temperature, heating and refluxing, and controlling the temperature in the reaction liquid to be 105-110 ℃ for reaction for 3 hours to mature;
(3) preparing a 20L reaction extraction device, adding 5.0L of tap water, slowly adding the reaction solution while stirring, standing for layering after dissolution and clarification, discarding the upper organic phase, extracting impurities from the lower aqueous phase by using toluene (3L multiplied by 2), adjusting the pH value of the obtained aqueous phase to 1 by using concentrated hydrochloric acid (680ml), cooling to 0-5 ℃, standing for 3 hours, performing suction filtration, performing suspension washing on a filter cake by using pure water (2L multiplied by 2), performing suction filtration to obtain 828g of wet solid, and finally performing air supply drying at 50 ℃ for 24 hours to obtain 501g of a dry intermediate;
(4) preparing a 2L glass reaction bottle, adding 1L of prepared 65% sulfuric acid solution, adding 501g of intermediate a little by little, stirring for dissolving, starting heating to raise the temperature, controlling the temperature at 130-140 ℃, reacting for 5h, and aging;
(5) after the reaction is finished, the reaction solution is returned to the room temperature, then the reaction solution is slowly poured into 1kg of crushed ice and 1L of water, stirred, added with toluene (1L multiplied by 3) for extraction, the organic phase toluene is combined, washed by saturated sodium bicarbonate solution (1.5L multiplied by 1), pure water (1.5L multiplied by 1) and saturated sodium chloride solution (1.5L multiplied by 2) in sequence, dried by 100G of magnesium sulfate, filtered by suction and concentrated to obtain crude 489G;
adding 489g of the crude product into a 1L distillation flask, heating by using an electric heating jacket, performing plus-minus distillation by using a 10cm thorn-shaped distillation column, and collecting a fraction with bp of 117-118 ℃/26mmHg to obtain 412g of the compound.
The nuclear magnetic resonance processing data, GC, specific gravity and refractive index of the prepared compound are detected as follows:
1H-NMR(CDCl3，400MHz，δppm)：δ＝7.30～7.32(2H，m)，7.25(1H，m)，7.20～7.22(2H，m)，3.68(2H，s)，2.44～2.47(2H，m)，1.01～1.04(3H，m)ppm
GC：99.8％
d20/20：0.9887
n20/D：1.5116
from the above data, it can be seen that the compound obtained above is 1-phenyl-2-butanone with a total yield of 96%.
Claims (6)
1. A method for synthesizing 1-phenyl-2-butanone is characterized by comprising the following steps:
step 1): adding sodium methoxide in batches at 20-25 ℃ by using dimethylbenzene as a solvent, dropwise adding phenylacetonitrile after the sodium methoxide is added, and stirring after the phenylacetonitrile is dropwise added;
step 2): placing the reaction liquid obtained in the step 1) in an ice water bath, cooling to 0-10 ℃, starting to dropwise add ethyl propionate, withdrawing the ice water bath after dropwise adding, recovering to room temperature, then heating and refluxing, and controlling the temperature in the reaction liquid to be 105-110 ℃ for reaction and ripening;
step 3): adding the reaction liquid obtained in the step 2) into water, and standing and layering after reaction quenching; removing the organic phase on the upper layer, continuously extracting impurities from the water phase on the lower layer by using methylbenzene, and keeping a water layer; adjusting the pH value of the water phase to 1-2 by using concentrated hydrochloric acid to generate a solid, cooling to 0-5 ℃, standing, performing suction filtration on a filter cake after 2 times of suspension washing by using water, and performing air supply drying on the obtained solid at 50 ℃ for 24 hours to obtain an intermediate;
step 4): adding the intermediate obtained in the step 3) into a sulfuric acid solution, heating after adding, maintaining the temperature in the reaction at 130-140 ℃, and reacting and ripening;
step 5): adding the reaction liquid obtained in the step 4) into crushed ice, carrying out reaction quenching, then extracting with toluene, combining organic phases, washing with a saturated sodium bicarbonate solution, water and a sodium chloride solution in sequence, drying with magnesium sulfate, and then concentrating to obtain a crude concentrated solution; and (4) carrying out reduced pressure distillation on the crude product, and collecting 117-118 ℃/26mmHg fractions.
2. The method for synthesizing 1-phenyl-2-butanone according to claim 1, wherein the step 1) specifically comprises: adding dimethylbenzene into a container, adding sodium methoxide in batches while stirring at the temperature of 20-25 ℃, adding the sodium methoxide in three times, starting to dropwise add phenylacetonitrile after the addition is finished, and stirring for 0.5h after the dropwise addition is finished; the weight ratio of the volume of the xylene to the phenylacetonitrile is 13-15L/kg, and the molar ratio of the sodium methoxide to the phenylacetonitrile is (2-3): 1.
3. the method for synthesizing 1-phenyl-2-butanone according to claim 1, wherein the step 2) specifically comprises: cooling the reaction liquid obtained in the step 1) to 0-10 ℃, dropwise adding ethyl propionate, withdrawing an ice water bath after dropwise adding, recovering to room temperature, heating and refluxing, and controlling the temperature in the reaction liquid to be 105-110 ℃ for reaction for 3h and ripening; the molar ratio of the ethyl propionate to the phenylacetonitrile is (2.5-3): 1.
4. the method for synthesizing 1-phenyl-2-butanone according to claim 1, wherein the step 3) specifically comprises: slowly adding the reaction solution obtained in the step 2) into water, and standing and layering after quenching reaction; removing the organic phase on the upper layer, continuously extracting impurities from the water phase on the lower layer by using methylbenzene, and keeping a water layer; adjusting the pH value of the water phase to 1-2 by using concentrated hydrochloric acid, generating a large amount of solid, cooling to 0-5 ℃, standing for 3h, carrying out suction filtration, carrying out suspension washing on a filter cake for 2 times by using water, carrying out suction filtration, and carrying out air supply drying on the obtained solid at 50 ℃ for 24h to obtain an intermediate; wherein, the ratio of the toluene volume required by extracting impurities to the reaction liquid volume is 0.5: 1, 2 extractions are required.
5. The method for synthesizing 1-phenyl-2-butanone according to claim 1, wherein the step 4) specifically comprises: slowly adding the intermediate obtained in the step 3) into a sulfuric acid solution with the mass concentration of 65%, heating after adding, and keeping the reaction temperature at 130-140 ℃ for reaction for 5 hours to mature; the weight ratio of the volume required by the sulfuric acid to the intermediate is 1.5-2L/kg.
6. The method for synthesizing 1-phenyl-2-butanone according to claim 1, wherein the step 5) specifically comprises: slowly adding the reaction liquid obtained in the step 4) into crushed ice, extracting with toluene after reaction quenching, combining organic phases, washing with saturated sodium bicarbonate solution, water and sodium chloride solution in sequence, drying with magnesium sulfate, and concentrating to obtain a crude concentrated solution; and (4) carrying out reduced pressure distillation on the crude product, and collecting 117-118 ℃/26mmHg fractions.
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| CN109796317A (en) * | 2019-01-14 | 2019-05-24 | 国药集团化学试剂有限公司 | A kind of preparation method of 1- Phenyl 2 butanone |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109796317A (en) * | 2019-01-14 | 2019-05-24 | 国药集团化学试剂有限公司 | A kind of preparation method of 1- Phenyl 2 butanone |
Non-Patent Citations (2)
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| MILES, DILLON H.等: "A Nucleophilic Strategy for Enantioselective Intermolecular α-Amination: Access to Enantioenriched α-Arylamino Ketones" * |
| XU, CHUANGCHUANG等: "An expeditious method to synthesize difluoroboron complexes of β-keto amides from β-keto nitriles and BF3•OEt2" * |
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