CN113754524B - Production and manufacturing method of m-fluorobenzaldehyde - Google Patents
Production and manufacturing method of m-fluorobenzaldehyde Download PDFInfo
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- CN113754524B CN113754524B CN202111127423.6A CN202111127423A CN113754524B CN 113754524 B CN113754524 B CN 113754524B CN 202111127423 A CN202111127423 A CN 202111127423A CN 113754524 B CN113754524 B CN 113754524B
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Abstract
The application belongs to the technical field of organic synthesis processes, and particularly relates to a production and manufacturing method of m-fluorobenzaldehyde. Benzene is used as a raw material to generate benzaldehyde through a series of reactions, the benzaldehyde reacts with 2-ethylhexyl amine, an intermediate I is obtained after layering and drying, an intermediate II is obtained after reacting with ammonium fluoride under the action of a phase transfer catalyst, and the intermediate II is protected by aldehyde groups to obtain m-fluorobenzaldehyde.
Description
Technical Field
The application relates to the technical field of organic synthesis processes, in particular to a method for producing and manufacturing m-fluorobenzaldehyde.
Background
The m-fluorobenzaldehyde is colorless or pale yellow liquid, has pungent smell, is easily oxidized into m-fluorobenzoic acid by oxygen in air, and should be stored in a closed manner. The m-fluorobenzaldehyde is an important organic synthesis intermediate and can be widely applied to the synthesis of fine chemicals such as medicines, pesticides, plastic additives and the like. The fluorine is introduced into the dye to enhance the luster and the brilliance of the dye and improve the properties of sun resistance, water resistance, organic solvent resistance and the like. In addition, the activity of aldehyde groups makes m-fluorobenzaldehyde an important intermediate for synthesizing fine chemical products such as medicines, pesticides, dyes and the like. Methods for synthesizing aromatic aldehydes include chemical oxidation, electrolytic oxidation, gas phase oxidation, and the like. The chemical oxidation method uses heavy metal oxidant, and a large amount of metal salt is produced as a byproduct during the synthesis of the aromatic aldehyde, so that the heavy metal content exceeds the standard, the environmental pollution is serious, and the industrialization is limited; the electrolytic oxidation has the characteristics of good selectivity, high yield, easy separation of products, mild conditions and the like, but the electrochemical method has large equipment investment, the electrodes are generally expensive rare metals, the yield is low, the industrialized mass production is difficult to realize, and the concentration of metal ions in the electrolyte is high, so that the environmental pollution is easy to cause; the gas-phase air oxidation method has the advantages of high speed, high efficiency, no need of solvent, no corrosiveness to equipment, but high requirement on a solid catalyst, and in addition, the gas-phase oxidation method uses gaseous oxygen as an oxidant, the mixed explosion limit of materials and oxygen is wide, and the reaction is a strong exothermic reaction, so that potential safety hazards exist.
Chinese patent 201610972046.9 discloses a method for preparing m-fluorobenzaldehyde by continuously oxidizing m-fluorotoluene, which takes m-fluorotoluene compound as a raw material, one or more metal ion complexes of cobalt, molybdenum and bromine as a catalyst, hydrogen peroxide as an oxidant and acetic acid as a solvent, and can realize the preparation of m-fluorobenzaldehyde by continuously oxidizing m-fluorotoluene in a tubular reactor.
Disclosure of Invention
Aiming at the problems that the byproducts are more in the production process, the equipment investment is large, and the industrialized mass production is difficult to realize, the application provides the m-fluorobenzaldehyde production and manufacturing method which has high product purity and less byproducts.
The technical scheme for solving the problems is as follows:
the m-fluorobenzaldehyde producing and manufacturing method comprises the following preparation steps:
s1, introducing methyl chloride into benzene, adding aluminum chloride, uniformly stirring, heating to raise the temperature, introducing chlorine under the illumination condition after reacting for 4-6 hours, then adding sodium hydroxide aqueous solution, adding copper powder as a catalyst, heating, and filtering after the reaction is completed to obtain benzaldehyde;
s2, adding benzaldehyde into a reaction kettle, reducing the temperature to a certain level, slowly adding 2-ethylhexyl amine into the reaction kettle, starting stirring, heating to raise the temperature for reaction after stirring uniformly, cooling to room temperature after the reaction is completed, and drying an organic layer by using a drying agent after layering to obtain an intermediate I;
s3, mixing the intermediate I with a solvent, adding ammonium fluoride and a phase transfer catalyst into the mixture, starting stirring and raising the temperature, and reacting for 3-5h to obtain an intermediate II after the reaction is completed;
s4, adding phosphoric acid into the intermediate II, starting stirring, raising the temperature, and performing reduced pressure distillation after the reaction is completed to obtain the m-fluorobenzaldehyde.
The application has the following beneficial effects:
1. in the process of synthesizing m-fluorobenzaldehyde from benzaldehyde, a group with a larger steric hindrance effect is introduced into a benzene ring by utilizing the reaction of benzaldehyde and 2-ethylhexyl amine, so that the attack on ortho-position is effectively blocked, the generation of ortho-position byproducts is reduced, and the purity of the product is greatly improved;
2. the synthetic route is simple in the reaction process, the operation is simple, and the operation is easy;
3. the raw materials used in the application are cheap and easy to obtain, the equipment investment is small, and the industrial mass production is easy.
Detailed Description
The following description of the embodiments of the present application will be made clearly and completely, and it is apparent that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
Example 1
The m-fluorobenzaldehyde producing and manufacturing method comprises the following preparation steps:
s1, synthesizing benzaldehyde: adding 30 parts by weight of benzene into methyl chloride, adding 12 parts by weight of aluminum chloride, uniformly stirring, heating to a temperature of 50 ℃, adding chlorine under the illumination condition after reacting for 4 hours, adding 35 parts by weight of sodium hydroxide aqueous solution, adding 6 parts by weight of copper powder as a catalyst, heating to 80 ℃, and filtering after the reaction is completed to obtain benzaldehyde;
s2, protecting aldehyde group: adding 25 parts by weight of benzaldehyde into a reaction kettle, reducing the temperature to 5 ℃, slowly adding 30 parts by weight of 2-ethylhexyl amine into the reaction kettle, starting stirring, heating to the temperature of 30 ℃ after uniformly stirring for reacting for 2 hours, cooling to the room temperature after the reaction is finished, and drying an organic layer by using anhydrous calcium chloride drier after layering to obtain an intermediate I, wherein the reaction process is as follows:
s3, introducing fluorine: 20 parts by weight of intermediate I and 50 parts by weight of N, N-dimethylformamide were mixed, and 25 parts by weight of ammonium fluoride and 15 parts by weight of benzyltriethylammonium chloride were added thereto, stirring was started and the temperature was raised to 85℃and the reaction was completed to obtain intermediate II, the reaction process was as follows:
s4, aldehyde group removal protection: adding 12 parts by weight of phosphoric acid into 15 parts by weight of intermediate II, starting stirring, raising the temperature to 45 ℃, and carrying out reduced pressure distillation after the reaction is completed to obtain m-fluorobenzaldehyde, wherein the purity of the m-fluorobenzaldehyde reaches 98.2% through gas chromatography analysis, and the reaction process is as follows:
specifically, the aldehyde group is a meta-position locating group, has an electron-withdrawing effect, can reduce the electron cloud density on the benzene ring, has higher ortho-position and para-position passivation degree, and most of new substituent groups enter meta-position in substitution reaction to form meta-position isomers. However, ortho-position isomers and para-position isomers exist in the substitution process, and the passivation of aldehyde groups to para-position is more than that of ortho-position isomers, so that ortho-position is a main byproduct, in order to reduce the content of ortho-position and para-position byproducts, benzaldehyde and 2-ethylhexyl amine are reacted to generate an intermediate I, the aldehyde groups are protected, the substituent of benzene rings on the intermediate I has a larger steric hindrance effect compared with the aldehyde groups, and the generation of ortho-position byproducts can be effectively reduced when fluorine element substitution is carried out.
Example 2
The m-fluorobenzaldehyde producing and manufacturing method comprises the following preparation steps:
s1, synthesizing benzaldehyde: adding chloromethane into 50 parts by weight of benzene, adding 18 parts by weight of aluminum chloride, uniformly stirring, heating to a temperature of 65 ℃, adding chlorine under the illumination condition after reacting for 6 hours, adding 55 parts by weight of sodium hydroxide aqueous solution, adding 10 parts by weight of copper powder as a catalyst, heating to 90 ℃, and filtering after the reaction is completed to obtain benzaldehyde;
s2, protecting aldehyde group: adding 30 parts by weight of benzaldehyde into a reaction kettle, reducing the temperature to 5 ℃, slowly adding 40 parts by weight of 2-ethylhexyl amine into the reaction kettle, starting stirring, heating to 30 ℃ after uniform stirring for reaction for 4 hours, cooling to room temperature after the reaction is finished, and drying an organic layer by using drier anhydrous calcium chloride after layering to obtain an intermediate I, wherein the reaction process is as follows:
s3, introducing fluorine: 30 parts by weight of intermediate I and 60 parts by weight of N, N-dimethylformamide were mixed, 35 parts by weight of ammonium fluoride and 20 parts by weight of benzyltriethylammonium chloride were added thereto, stirring was started and the temperature was raised to 95℃and the reaction was carried out for 5 hours to obtain intermediate II after completion of the reaction, the reaction procedure was as follows:
s4, aldehyde group removal protection: adding 15 parts by weight of phosphoric acid into 25 parts by weight of intermediate II, starting stirring, raising the temperature to 55 ℃, and carrying out reduced pressure distillation after the reaction is completed to obtain m-fluorobenzaldehyde, wherein the purity of the m-fluorobenzaldehyde reaches 98.6% through gas chromatography analysis, and the reaction process is as follows:
example 3
The m-fluorobenzaldehyde producing and manufacturing method comprises the following preparation steps:
s1, synthesizing benzaldehyde: adding methyl chloride into 45 parts by weight of benzene, adding 16 parts by weight of aluminum chloride, uniformly stirring, heating to a temperature of 55 ℃, adding chlorine under the illumination condition after reacting for 5 hours, adding 45 parts by weight of sodium hydroxide aqueous solution, adding 8 parts by weight of copper powder as a catalyst, heating to 85 ℃, and filtering after the reaction is completed to obtain benzaldehyde;
s2, protecting aldehyde group: adding 28 parts by weight of benzaldehyde into a reaction kettle, reducing the temperature to 5 ℃, slowly adding 35 parts by weight of 2-ethylhexyl amine into the reaction kettle, starting stirring, heating to 30 ℃ after uniform stirring for reaction for 3 hours, cooling to room temperature after the reaction is finished, and drying an organic layer by using desiccant anhydrous calcium chloride after layering to obtain an intermediate I, wherein the reaction process is as follows:
s3, introducing fluorine: 25 parts by weight of intermediate I was mixed with 55 parts by weight of N, N-dimethylformamide, and 30 parts by weight of ammonium fluoride and 16 parts by weight of benzyltriethylammonium chloride were added thereto, stirring was started and the temperature was raised to 90℃and the reaction was carried out for 4 hours to obtain intermediate II after completion of the reaction, the reaction procedure was as follows:
s4, aldehyde group removal protection: 13 parts by weight of phosphoric acid is added into 18 parts by weight of intermediate II, stirring is started, the temperature is increased to 50 ℃, after the reaction is completed, reduced pressure distillation is carried out, and the m-fluorobenzaldehyde is obtained, the purity reaches 99.6% through gas chromatography analysis, and the reaction process is as follows:
example 4
The m-fluorobenzaldehyde producing and manufacturing method comprises the following preparation steps:
s1, synthesizing benzaldehyde: adding chloromethane into 42 parts by weight of benzene, adding 14 parts by weight of aluminum chloride, uniformly stirring, heating to a temperature of 55 ℃, adding chlorine under the illumination condition after reacting for 5 hours, adding 42 parts by weight of sodium hydroxide aqueous solution, adding 7 parts by weight of copper powder as a catalyst, heating to 85 ℃, and filtering after the reaction is completed to obtain benzaldehyde;
s2, protecting aldehyde group: adding 26 parts by weight of benzaldehyde into a reaction kettle, reducing the temperature to 5 ℃, slowly adding 32 parts by weight of 2-ethylhexyl amine into the reaction kettle, starting stirring, heating to 30 ℃ after uniform stirring for reacting for 2.5 hours, cooling to room temperature after the reaction is finished, and drying an organic layer by using drier anhydrous calcium chloride after layering to obtain an intermediate I, wherein the reaction process is as follows:
s3, introducing fluorine: 22 parts by weight of intermediate I and 55 parts by weight of acetone are mixed, 28 parts by weight of ammonium fluoride and 16 parts by weight of tributylamine are added, stirring is started, the temperature is raised to 88 ℃, the reaction is carried out for 3.5 hours, and an intermediate II is obtained after the reaction is finished, wherein the reaction process is as follows:
s4, aldehyde group removal protection: 13 parts by weight of phosphoric acid is added into 16 parts by weight of intermediate II, stirring is started, the temperature is increased to 50 ℃, after the reaction is completed, reduced pressure distillation is carried out, and the m-fluorobenzaldehyde with the purity of 99.1% by gas chromatography analysis is obtained, wherein the reaction process is as follows:
as can be seen from the above examples, the purity of the m-fluorobenzaldehyde prepared by the method is high and can reach 99.6%. The application firstly uses benzene as raw material to prepare benzaldehyde, then uses the reaction of the benzaldehyde and 2-ethylhexyl amine to protect aldehyde group, and although the aldehyde group is meta-position locating group, during the reaction, o-position and para-position byproducts are inevitably generated, especially because the passivation of the aldehyde group to para-position is more than ortho-position, the ortho-position byproducts become main byproducts. In the application, as the substituent of the benzene ring on the intermediate I has a larger steric hindrance effect compared with aldehyde group, the attack of fluorine on the ortho-position can be reduced, the generation of ortho-position byproducts is reduced, and the purity of the product is improved; the synthetic route is simple in the reaction process, the operation is easy, the raw materials are cheap and easy to obtain, and the method is favorable for industrial production.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the application, the scope of which is defined in the appended claims and their equivalents.
Claims (1)
1. The production and manufacturing method of the m-fluorobenzaldehyde is characterized by comprising the following preparation steps:
s1, synthesizing benzaldehyde: adding methyl chloride into 45 parts by weight of benzene, adding 16 parts by weight of aluminum chloride, uniformly stirring, heating to a temperature of 55 ℃, adding chlorine under the illumination condition after reacting for 5 hours, adding 45 parts by weight of sodium hydroxide aqueous solution, adding 8 parts by weight of copper powder as a catalyst, heating to 85 ℃, and filtering after the reaction is completed to obtain benzaldehyde;
s2, protecting aldehyde group: adding 28 parts by weight of benzaldehyde into a reaction kettle, reducing the temperature to 5 ℃, slowly adding 35 parts by weight of 2-ethylhexyl amine into the reaction kettle, starting stirring, heating to 30 ℃ for reaction for 3 hours after uniform stirring, cooling to room temperature after the reaction is finished, and drying an organic layer by using desiccant anhydrous calcium chloride after layering to obtain an intermediate I;
s3, introducing fluorine: mixing 25 parts by weight of the intermediate I with 55 parts by weight of N, N-dimethylformamide, adding 30 parts by weight of ammonium fluoride and 16 parts by weight of phase transfer catalyst benzyl triethyl ammonium chloride, starting stirring, raising the temperature to 90 ℃, and reacting for 4 hours to obtain an intermediate II after the reaction is completed;
s4, aldehyde group removal protection: 13 parts by weight of phosphoric acid was added to 18 parts by weight of intermediate II, stirring was started, the temperature was increased to 50℃and, after the completion of the reaction, vacuum distillation was performed to obtain m-fluorobenzaldehyde.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101374516A (en) * | 2006-01-27 | 2009-02-25 | 弗·哈夫曼-拉罗切有限公司 | Use of substituted 2-imidazole of imidazoline derivatives |
| CN102617312A (en) * | 2012-03-19 | 2012-08-01 | 丹阳市万隆化工有限公司 | Method for preparing 2-chloro-6-fluorobenzaldehyde |
| CN104447251A (en) * | 2014-12-24 | 2015-03-25 | 常熟市新华化工有限公司 | Synthetic method of p-chlorobenzaldehyde |
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| US20180230105A1 (en) * | 2017-01-13 | 2018-08-16 | Regents Of The University Of Minnesota | Therapeutic compounds |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101374516A (en) * | 2006-01-27 | 2009-02-25 | 弗·哈夫曼-拉罗切有限公司 | Use of substituted 2-imidazole of imidazoline derivatives |
| CN102617312A (en) * | 2012-03-19 | 2012-08-01 | 丹阳市万隆化工有限公司 | Method for preparing 2-chloro-6-fluorobenzaldehyde |
| CN104447251A (en) * | 2014-12-24 | 2015-03-25 | 常熟市新华化工有限公司 | Synthetic method of p-chlorobenzaldehyde |
Non-Patent Citations (1)
| Title |
|---|
| Tunable Photocontrolled Motions of Anil-Poly(ethylene terephthalate) Systems through Excited-State Intramolecular Proton Transfer and Trans-Cis Isomerization;Huang, Arui 等;Adv. Mater.;第33卷(第5期);1-7 * |
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