CN113402410A - Method for efficiently preparing 3, 4-dichlorophenyl propionamide - Google Patents
Method for efficiently preparing 3, 4-dichlorophenyl propionamide Download PDFInfo
- Publication number
- CN113402410A CN113402410A CN202110641544.6A CN202110641544A CN113402410A CN 113402410 A CN113402410 A CN 113402410A CN 202110641544 A CN202110641544 A CN 202110641544A CN 113402410 A CN113402410 A CN 113402410A
- Authority
- CN
- China
- Prior art keywords
- propionic acid
- reaction
- dichloroaniline
- propionic
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/02—Preparation of carboxylic acid amides from carboxylic acids or from esters, anhydrides, or halides thereof by reaction with ammonia or amines
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/22—Separation; Purification; Stabilisation; Use of additives
- C07C231/24—Separation; Purification
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for efficiently preparing 3, 4-dichlorophenyl propionamide, which takes 3, 4-dichloroaniline, propionic acid and propionic anhydride as raw materials to carry out condensation reaction in the presence of a catalyst to synthesize the 3, 4-dichlorophenyl propionamide. The propionic anhydride is added into the raw materials, and can react with water formed by reaction to form propionic acid, so that the propionic anhydride plays a role of a dehydrating agent, the reaction speed is accelerated, the condensation time is shortened to 3-3.5h, the production efficiency is greatly improved, the dehydration step after the condensation reaction is omitted, the process flow is simplified, and the cost and the energy consumption are reduced. The water content of the propionic acid recovered after the condensation reaction is below 0.3 percent, the propionic acid can be directly used indiscriminately without treatment, the reaction is still normally carried out after the indiscriminate use, and the product is qualified. The invention does not use a phosphorus-containing catalyst, does not generate three wastes, and is more in line with the construction of green chemical engineering.
Description
Technical Field
The invention relates to a preparation method of 3, 4-dichlorophenyl propionamide (propanil) raw drug, in particular to a method for efficiently preparing 3, 4-dichlorophenyl propionamide, belonging to the technical field of organic synthesis.
Background
Propanil (chemical name: 3, 4-dichlorophenyl propionamide) is a high-selectivity amide contact herbicide, is mainly used in rice seedling fields or direct seeding fields, is a specific drug for preventing and killing barnyard grass, and can also be used for preventing and killing other various graminaceous and dicotyledonous weeds, such as monochoria vaginalis, cress, digitaria sanguinalis, green bristlegrass and the like. The propanil is hardly conducted in the plant body, only acts on the contact part of the medicament, has various action mechanisms, not only destroys the photosynthesis of the plant, but also inhibits the respiration and the oxyphosphorylation, interferes with the synthesis of nucleic acid and protein and the like, thereby influencing the physiological function of sensitive plants, accelerating the water loss, gradually drying leaves and finally dying. The propanil is rapidly decomposed into non-toxic substances in the rice by hydrolase, the degradation capability of the rice to the propanil is 20 times greater than that of the propanil, so that the propanil is safe to the rice, and the propanil emulsifiable concentrate with 20 percent is used for the period from two leaves to three leaves of the propanil to one heart when the propanil is used2Adding 5.3kg of water to prepare stem leaves for spray treatment. Draining off water layer before spraying, spraying after the next day, irrigating water for 24 hr, and maintaining for 2 days.
At present, the synthesis research of propanil has less reports, and the main synthesis method comprises the following steps: chlorobenzene is used as a raw material, 3, 4-dichloroaniline is obtained through nitration, chlorination and reduction, and then 3, 4-dichloroaniline and propionic acid are condensed to obtain propanil, wherein the reaction flow is as follows:
in the above synthesis method, the condensation reaction of 3, 4-dichloroaniline and propionic acid may or may not be carried out under a catalyst. When the 3, 4-dichloroaniline and the propionic acid are condensed in the absence of a catalyst, the condensation reaction time is longer and is about 15 hours, when the condensation is performed in the presence of the catalyst, the used catalyst is phosphorus oxychloride, the condensation time can be shortened to 6-8 hours, but the condensation time is still longer, and the existence of the catalyst can generate a large amount of phosphorus-containing wastewater, so that great environmental protection pressure is caused. In addition, after the condensation reaction, the excess propionic acid needs to be distilled off, but because the propionic acid and water are mutually soluble and azeotropic, the water content in the removed propionic acid is high, generally more than 5%, and the propionic acid can be recycled to production after being treated.
Disclosure of Invention
Aiming at the defects of the existing propanil synthesis method, the invention provides a method for efficiently preparing 3, 4-dichlorophenyl propionamide, which improves the condensation reaction process of 3, 4-dichloroaniline and propionic acid, greatly shortens the condensation reaction time, improves the production efficiency, does not generate a large amount of waste water, and has good environmental protection property.
The specific technical scheme of the invention is as follows:
a process for preparing 3, 4-dichlorophenyl propionamide in high efficiency includes the step of taking 3, 4-dichloroaniline, propionic acid and propionic anhydride as raw materials, carrying out condensation reaction in the presence of catalyst to synthesize 3, 4-dichlorophenyl propionamide.
The invention takes 3, 4-dichloroaniline, propionic acid and propionic anhydride as raw materials, wherein the propionic anhydride is taken as a dehydrating agent and can also provide a propionic acid raw material for reaction, and the reaction formula is as follows:
as can be seen from the reaction formula, water formed by condensation reaction of 3, 4-dichloroaniline and propionic acid reacts with propionic anhydride to form propionic acid, and the propionic anhydride plays a role of a dehydrating agent and absorbs and converts the water formed by the reaction into the propionic acid, so that dehydration is realized during the reaction, the dehydration process is omitted, the process flow is simplified, three wastes and energy consumption are reduced, and the environment-friendly chemical method is more suitable for green chemistry. In addition, the method obviously shortens the whole reaction time, greatly improves the working efficiency, has low operation difficulty and is easier to realize industrial production.
Further, in the above reaction, the catalyst is one or more of polyethylene glycol-800, polyethylene glycol-600, tetrabutylammonium bromide, benzyltriethylammonium chloride, tetrabutylammonium chloride and disodium ethylenediaminetetraacetate, preferably disodium ethylenediaminetetraacetate, or a mixture of disodium ethylenediaminetetraacetate and tetrabutylammonium chloride in a mass ratio of 2-4: 1.
Further, the mass of the catalyst is 0.1-0.5%, preferably 0.3% of that of 3, 4-dichloroaniline.
Further, 3, 4-dichloroaniline: propionic acid: the molar ratio of propionic anhydride is 1: 0.1-0.5: 0.7-1, and the molar quantity of the propionic anhydride is larger than that of the propionic acid so as to fully absorb the water in the reaction process. Preferably, 3, 4-dichloroaniline: propionic acid: the molar ratio of propionic anhydride is 1: 0.5: 1.
further, the 3, 4-dichloroaniline used in the present invention can be either directly commercially available or can be prepared by itself according to the methods disclosed in the prior art.
Further, the condensation reaction comprises the following specific steps: during the condensation reaction, 3, 4-dichloroaniline, propionic acid, propionic anhydride and catalyst are mixed and heated to reflux temperature for condensation reaction. Typically, the reflux temperature is in the range of 148 ℃ and 152 ℃. Due to the addition of the propionic anhydride, water formed by the reaction can be absorbed, the forward progress of the reaction is promoted, the time of the condensation reaction is shortened, the dehydration step is avoided, and the production efficiency is greatly improved.
Furthermore, during the condensation reaction, the reaction end point is judged by detecting the unconverted residual amount of the raw materials, generally, the reaction can be finished when the unconverted residual amount of the raw materials is less than 0.1 percent, and the time of the condensation reaction in the method of the invention is generally 3-3.5 h.
Further, after the condensation reaction, the method also comprises the step of carrying out reduced pressure distillation on the reaction liquid to remove the propionic acid, and the method recovers the propionic acid through reduced pressure distillation, wherein the water content of the propionic acid is lower than 0.3wt%, and the water content is very low, so that the use requirement is met. Therefore, the obtained propionic acid can be directly reused as a raw material without being treated.
Further, the specific steps of removing the propionic acid by reduced pressure distillation are as follows: after condensation reaction, under the negative pressure of-0.08 to-0.09 MPa, the temperature is raised to 80 ℃, propionic acid is evaporated, then the temperature is raised continuously until 160 ℃, and the temperature is kept at 160 ℃ until no propionic acid is removed.
The invention takes 3, 4-dichloroaniline as raw material, propionic anhydride and catalyst are added, and 3, 4-dichlorophenyl propionamide, namely propanil, is synthesized through condensation reaction. Compared with the prior art, the invention has the following advantages:
1. the propionic anhydride is added into the raw materials, and can react with water formed by reaction to form propionic acid, so that the propionic anhydride plays a role of a dehydrating agent, the reaction speed is accelerated, the condensation time is shortened to 3-3.5h, the production efficiency is greatly improved, the dehydration step after the condensation reaction is omitted, the process flow is simplified, and the cost and the energy consumption are reduced.
2. The water content of the propionic acid recovered after the condensation reaction is below 0.3 percent, the propionic acid can be directly used indiscriminately without treatment, the reaction is still normally carried out after the indiscriminate use, and the product is qualified.
3. The invention does not use a phosphorus-containing catalyst, does not generate three wastes, and is more in line with the construction of green chemical engineering.
4. The method has the advantages of low raw material cost, low equipment requirement, mild reaction condition, high safety coefficient, good reaction selectivity, no obvious side reaction, high reaction conversion rate, high product yield and high purity, and is suitable for industrial mass production.
Drawings
FIG. 1 is a process flow diagram for the preparation of 3, 4-dichlorophenyl propionamide according to the present invention.
FIG. 2 is an HPLC high performance liquid chromatography of 3, 4-dichlorophenyl propionamide obtained in example 1.
FIG. 3 is an HPLC high performance liquid chromatogram of a 3, 4-dichlorophenyl propionamide standard.
Detailed Description
The present invention is further illustrated by the following specific examples, which are intended to be exemplary only and are not intended to be limiting.
Unless otherwise specified, the contents in the following examples are all by mass%.
Example 1
162.02g of 98% 3, 4-dichloroaniline, 37.00g of 98% propionic acid, 130.14g of 98% propionic anhydride and 0.50g of 99% disodium ethylene diamine tetraacetate are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out for 3 hours, the reaction is finished, the reaction solution does not rotate by 0.07% and the propanil-I content is 99.65% through detection, the reaction is finished (if the reaction does not rotate by more than 0.1%, the reaction needs to be prolonged for half an hour, and detection is carried out until the reaction does not rotate by less than 0.1%). Removing propionic acid under negative pressure of-0.085 MPa, heating to 80 ℃ under negative pressure, distilling off propionic acid, continuously heating to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the obtained propionic acid with the water content of below 0.3 percent as a raw material, wherein the remainder after removing the propionic acid is propanil, the product has the content of 97.9 percent through HPLC detection, and the yield is 98.2 percent calculated by 3, 4-dichloroaniline.
Example 2
81.01g of 98% 3, 4-dichloroaniline, 18.50g of 98% propionic acid, 65.07g of 98% propionic anhydride and 0.25g of 99% disodium ethylene diamine tetraacetate are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, the reflux heat preservation reaction is carried out for 3 hours, the reaction is finished, the reaction solution is detected to be not converted by 0.08%, the propanil mono-content is 99.65%, the reaction is finished (if the reaction solution is not converted by more than 0.1%, the reaction is required to be prolonged for half an hour, and the detection is carried out until the reaction solution is not converted by less than 0.1%). Under the negative pressure of-0.085 mPa, removing propionic acid, heating to 80 ℃ under the negative pressure, evaporating propionic acid, then continuously heating until the temperature is increased to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the propionic acid as a raw material, wherein the remainder after removing the propionic acid is the propanil, the content of the product is 97.8 percent through HPLC detection, and the yield is 98.2 percent calculated by 3, 4-dichloroaniline.
Example 3
324.04g of 98 percent 3, 4-dichloroaniline, 74.00g of 98 percent propionic acid, 260.28g of 98 percent propionic anhydride and 1.00g of 99 percent disodium ethylene diamine tetraacetate are added into a 1L four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out for 3 hours, after the reaction is finished, the reaction solution is detected not to be rotated by 0.07 percent, the propanil-I content is detected to be 99.65 percent, the reaction is finished (if the reaction is not rotated by more than 0.1 percent, the reaction is required to be prolonged for half an hour, and detection is carried out until the reaction is not rotated by less than 0.1 percent). Under the negative pressure of-0.085 mPa, removing propionic acid, heating to 80 ℃ under the negative pressure, evaporating propionic acid, then continuously heating until the temperature is increased to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the propionic acid as a raw material, wherein the remainder after removing the propionic acid is propanil, the content of the product is 98.2% through HPLC detection, and the yield is 98.3% by 3, 4-dichloroaniline.
Example 4
121.52g of 98% 3, 4-dichloroaniline, 27.75g of 98% propionic acid, 97.61g of 98% propionic anhydride and 0.33g of 99% disodium ethylene diamine tetraacetate are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out for 3 hours, the reaction is finished, the reaction solution does not rotate by 0.08% and the propanil mono-content is 99.65% through detection, the reaction is finished (if the reaction does not rotate by more than 0.1%, the reaction needs to be prolonged for half an hour, and detection is carried out until the reaction does not rotate by less than 0.1%). Under the negative pressure of-0.085 mPa, removing propionic acid, heating to 80 ℃ under the negative pressure, evaporating propionic acid, then continuously heating until the temperature is increased to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the propionic acid as a raw material, wherein the remainder after removing the propionic acid is propanil, the content of the product is 98.1% through HPLC detection, and the yield is 98.4% by 3, 4-dichloroaniline.
Example 5
Adding 243.08 98% 3, 4-dichloroaniline, 55.5g 98% propionic acid, 65.07g 98% propionic anhydride and 0.75g 99% disodium ethylenediamine tetraacetic acid into a 500mL four-neck flask, slowly heating to the reflux temperature of 150 ℃, carrying out reflux heat preservation reaction for 3h, detecting that the reaction solution does not turn 0.07% and the propanil mono-content is 99.65% after the reaction is finished, and finishing the reaction (if the reaction solution does not turn more than 0.1%, prolonging the reaction for half an hour and detecting until the reaction does not turn less than 0.1%). Under the negative pressure of-0.085 mPa, removing propionic acid, heating to 80 ℃ under the negative pressure, evaporating propionic acid, then continuously heating until the temperature is increased to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the propionic acid as a raw material, wherein the remainder after removing the propionic acid is propanil, the product has the content of 98.0 percent through HPLC detection, and the yield is 98.5 percent calculated by 3, 4-dichloroaniline.
Example 6
162.02g of 98% 3, 4-dichloroaniline, 18.50g of 98% propionic acid, 130.14g of 98% propionic anhydride and 0.50g of 99% disodium ethylene diamine tetraacetate are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out for 3 hours, the reaction is finished, the reaction solution does not rotate by 0.07% and the propanil-I content is 99.65% through detection, the reaction is finished (if the reaction does not rotate by more than 0.1%, the reaction needs to be prolonged for half an hour, and detection is carried out until the reaction does not rotate by less than 0.1%). Removing propionic acid under the negative pressure of-0.085 MPa, heating to 80 ℃ under the negative pressure, distilling off propionic acid, continuously heating until the temperature is increased to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the propionic acid as a raw material, wherein the remainder after removing the propionic acid is the propanil, the content of the product is 97.5 percent through HPLC detection, and the yield is 97.4 percent calculated by 3, 4-dichloroaniline.
Example 7
162.02g of 98% 3, 4-dichloroaniline, 8.50g of 98% propionic acid, 130.14g of 98% propionic anhydride and 0.50g of 99% disodium ethylene diamine tetraacetate are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out for 3 hours, the reaction is finished, the reaction solution is detected not to be rotated more than 0.1%, the reaction is prolonged for half an hour, the reaction solution is detected not to be rotated less than 0.1%, and the reaction is finished. Removing propionic acid under the negative pressure of-0.085 MPa, heating to 80 ℃ under the negative pressure, distilling off propionic acid, continuously heating until the temperature is increased to 160 ℃, keeping the temperature for 30min at the temperature until no propionic acid is removed, stopping heating, cooling, and directly recycling the propionic acid as a raw material, wherein the remainder after removing the propionic acid is the propanil, the content of the product is 97.4 percent through HPLC detection, and the yield is 97.1 percent calculated by 3, 4-dichloroaniline.
Example 8
Propanil was prepared as in example 1 except that: the amount of propionic anhydride added, having a content of 98%, was 97.61 g. The HPLC detection shows that the product content is 97.8 percent, and the yield is 97.6 percent calculated by 3, 4-dichloroaniline.
Example 9
Propanil was prepared as in example 1 except that: 0.50g of disodium edetate with a content of 99% was replaced by 0.50g of tetrabutylammonium bromide with a content of 99%. The HPLC detection shows that the product content is 97.1 percent, and the yield is 97.2 percent calculated by 3, 4-dichloroaniline.
Example 10
Propanil was prepared as in example 1 except that: 0.50g of disodium edetate with the content of 99 percent is replaced by 0.50g of polyethylene glycol-800 with the content of 99 percent. HPLC detection shows that the product content is 96.4%, and the yield is 96.6% based on 3, 4-dichloroaniline.
Example 11
Propanil was prepared as in example 1 except that: 0.50g of disodium edetate with a content of 99% is replaced by 0.50g of benzyltriethylammonium chloride with a content of 99%. The HPLC detection shows that the product content is 97.2 percent, and the yield is 97.4 percent calculated by 3, 4-dichloroaniline.
Example 12
Propanil was prepared as in example 1 except that: 0.2g of disodium edetate with a content of 99% is added. The HPLC detection shows that the product content is 97.5 percent, and the yield is 97.9 percent calculated by 3, 4-dichloroaniline.
Example 13
Propanil was prepared as in example 1 except that: 0.8g of disodium edetate with a content of 99% is added. HPLC detection shows that the product content is 98.1%, and the yield is 98.4% based on 3, 4-dichloroaniline.
Example 14
Propanil was prepared as in example 1 except that: 0.50g of disodium edetate with a content of 99% is replaced by 0.40g of disodium edetate with a content of 99% and 0.1g of 99% tetrabutylammonium chloride. HPLC detection shows that the product content is 99.2%, and the yield is 99.5% based on 3, 4-dichloroaniline.
Comparative example 1
162.02g of 98% 3, 4-dichloroaniline and 148.00g of 98% propionic acid are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 138 ℃, reflux and heat preservation are carried out for reaction for 15 hours, after the reaction is finished, the reaction liquid does not rotate less than 0.1% through detection, the reaction is finished (if the reaction liquid does not rotate more than 0.1%, the reaction needs to be prolonged for half an hour, and then the reaction is detected until the reaction liquid does not rotate less than 0.1%). Removing propionic acid under negative pressure of-0.085 MPa, heating to 80 deg.C under negative pressure, evaporating propionic acid, heating to 160 deg.C, maintaining the temperature for 30min, stopping heating, cooling to obtain propionic acid with water content of more than 5% and high water content, and can not be directly reused as raw material. The remainder after propionic acid removal is propanil, the content of the product is 97.1 percent through HPLC detection, and the yield is 97.5 percent calculated by 3, 4-dichloroaniline.
Comparative example 2
162.02g of 98% 3, 4-dichloroaniline, 37.00g of 98% propionic acid and 130.14g of 98% propionic anhydride are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out for 6 hours, the reaction is finished, the reaction solution is not reduced to less than 0.1% through detection, the reaction is finished (if the reaction solution is not reduced to more than 0.1%, the reaction needs to be prolonged for half an hour, and detection is carried out until the reaction solution is not reduced to less than 0.1%). Removing propionic acid under-0.085 MPa, heating to 80 ℃ under negative pressure, distilling propionic acid, heating to 160 ℃, keeping the temperature for 30min, stopping heating, cooling, wherein the water content of the obtained propionic acid is 0.3%, the remainder after removing propionic acid is propanil, the product has the content of 97.4% through HPLC detection, and the yield is 97.6% based on 3, 4-dichloroaniline.
Comparative example 3
162.02g of 98 percent 3, 4-dichloroaniline, 130.14g of 98 percent propionic anhydride and 0.50g of 99 percent disodium ethylene diamine tetraacetate are added into a 500mL four-neck flask, the temperature is slowly increased to the reflux temperature of 150 ℃, reflux heat preservation reaction is carried out, and the reaction does not occur under the anhydrous condition through detection.
Claims (10)
1. A method for preparing 3, 4-dichlorophenyl propionamide with high efficiency is characterized in that: comprises the step of synthesizing 3, 4-dichlorophenyl propionamide by taking 3, 4-dichloroaniline, propionic acid and propionic anhydride as raw materials and carrying out condensation reaction in the presence of a catalyst.
2. The method of claim 1, further comprising: the catalyst is one or more of polyethylene glycol-800, polyethylene glycol-600, tetrabutylammonium bromide, benzyltriethylammonium chloride, tetrabutylammonium chloride and disodium ethylene diamine tetraacetate, preferably disodium ethylene diamine tetraacetate, or a mixture of disodium ethylene diamine tetraacetate and tetrabutylammonium chloride in a mass ratio of 2-4: 1.
3. A method according to claim 1 or 2, characterized by: 3, 4-dichloroaniline: propionic acid: the molar ratio of propionic anhydride is 1: 0.1-0.5: 0.7-1, preferably 1: 0.5: 1.
4. a method according to claim 1 or 2, characterized by: the mass of the catalyst is 0.1-0.5%, preferably 0.3% of that of the 3, 4-dichloroaniline.
5. The method of claim 1, further comprising: during the condensation reaction, 3, 4-dichloroaniline, propionic acid, propionic anhydride and catalyst are mixed and heated to reflux temperature for condensation reaction.
6. The method of claim 5, wherein: the reflux temperature was 148 ℃ and 152 ℃.
7. The method of claim 1, 5 or 6, wherein: the condensation reaction time is 3-3.5 h.
8. The method according to any of claims 1-7, characterized by: after the condensation reaction, the method also comprises the step of removing the propionic acid by carrying out reduced pressure distillation on the reaction liquid, wherein the water content of the obtained propionic acid is lower than 0.3 wt%.
9. The method of claim 8, wherein: after condensation reaction, under the negative pressure of-0.08 to-0.09 MPa, the temperature is raised to 80 ℃, propionic acid is evaporated, then the temperature is raised continuously until 160 ℃, and the temperature is kept at 160 ℃ until no propionic acid is removed.
10. A method according to claim 8 or 9, characterized by: the removed propionic acid can be directly used as raw material for reuse without treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110641544.6A CN113402410B (en) | 2021-06-09 | 2021-06-09 | Method for efficiently preparing 3, 4-dichlorophenyl propionamide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110641544.6A CN113402410B (en) | 2021-06-09 | 2021-06-09 | Method for efficiently preparing 3, 4-dichlorophenyl propionamide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113402410A true CN113402410A (en) | 2021-09-17 |
| CN113402410B CN113402410B (en) | 2023-04-14 |
Family
ID=77683199
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110641544.6A Active CN113402410B (en) | 2021-06-09 | 2021-06-09 | Method for efficiently preparing 3, 4-dichlorophenyl propionamide |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113402410B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114230478A (en) * | 2021-12-24 | 2022-03-25 | 宁夏格瑞精细化工有限公司 | Catalytic synthesis method of propanil |
-
2021
- 2021-06-09 CN CN202110641544.6A patent/CN113402410B/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114230478A (en) * | 2021-12-24 | 2022-03-25 | 宁夏格瑞精细化工有限公司 | Catalytic synthesis method of propanil |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113402410B (en) | 2023-04-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113402410B (en) | Method for efficiently preparing 3, 4-dichlorophenyl propionamide | |
| JPH10502382A (en) | Process for producing ammonium-2-hydroxy-4- (methylthio) -butyrate, liquid mixture containing the same and use thereof | |
| EP0208948B1 (en) | A method for optical resolution of phenylacetic acid derivative | |
| US3836568A (en) | Process for production of lower alkyl esters of cis-chrysanthemum monocarboxylic acid | |
| US3993651A (en) | Triethylenediamine recovery | |
| JPH0232045A (en) | Production of alkylene carbonate | |
| CN112645894B (en) | Method for preparing sulpirazole intermediate 5, 5-dimethyl-4, 5-dihydroisoxazole-3-thiocarboxamidine hydrochloride | |
| JPH0430416B2 (en) | ||
| CN112094203B (en) | Preparation method of 1-cyano-2-propenyl acetate | |
| CN111320549B (en) | Continuous production method and device for propanil | |
| KR100823440B1 (en) | Method for preparing ethyl acetate of high purity from exhaust ethyl acetate | |
| JP2671152B2 (en) | Method for purifying 1-aminopropanediol | |
| SU1685915A1 (en) | Method for obtaining monochloroacetic acid | |
| US6215006B1 (en) | Process for the preparation of 3-isochromanoes by cyclization of o-chloromethylphenylacetic acids | |
| CN116730894A (en) | Preparation method of chlorfenapyr intermediate 2- (p-chlorophenyl) -5- (trifluoromethyl) pyrrole-3-nitrile | |
| JPS6360950A (en) | Hydroxyphenyl- and hydroxyphenoxyalkanoic acid iodopropargyl ester | |
| CN108658745B (en) | Preparation method of hinokitiol | |
| US20040127728A1 (en) | Process for the production of 5-benzyl-3-furfuryl alcohol | |
| SU1659400A1 (en) | Method for obtaining n,n-dimenthyl-n-(2,3-dichloropropyl) amine hydrochloride | |
| JPS6263544A (en) | Production of acrylic acid or methacrylic acid tertiary butyl ester | |
| US6500978B2 (en) | Process for producing cyclopropanecarbonitrile | |
| US4435568A (en) | Thiol methylation process-reaction, recycle and regeneration of methyl bromide | |
| CN115304538A (en) | Method for preparing 6,6-dimethyl-3-azabicyclo [3.1.0] hexane from isopentenol | |
| SU1586656A1 (en) | Regulator of cotton plant growth | |
| CN113896653A (en) | Synthesis and purification method of 2-chloro-6-fluorobenzonitrile |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |