CN113004131B - Preparation method of 2,4, 6-trichlorophenyl substituted acetone - Google Patents
Preparation method of 2,4, 6-trichlorophenyl substituted acetone Download PDFInfo
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- CN113004131B CN113004131B CN202110135549.1A CN202110135549A CN113004131B CN 113004131 B CN113004131 B CN 113004131B CN 202110135549 A CN202110135549 A CN 202110135549A CN 113004131 B CN113004131 B CN 113004131B
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- C07—ORGANIC CHEMISTRY
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- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/26—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by hydration of carbon-to-carbon triple bonds
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- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
- C07C17/10—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms
- C07C17/14—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms in the side-chain of aromatic compounds
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- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/26—Preparation of halogenated hydrocarbons by reactions involving an increase in the number of carbon atoms in the skeleton
- C07C17/263—Preparation of halogenated hydrocarbons by reactions involving an increase in the number of carbon atoms in the skeleton by condensation reactions
- C07C17/2632—Preparation of halogenated hydrocarbons by reactions involving an increase in the number of carbon atoms in the skeleton by condensation reactions involving an organo-magnesium compound, e.g. Grignard synthesis
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Abstract
The invention relates to a preparation method of 2,4, 6-trichlorophenyl substituted acetone, which comprises the steps of adding 2,4, 6-trichlorotoluene and a chlorinating agent into an organic solvent at a certain temperature to prepare 2,4, 6-trichlorophenyl benzyl chloride, coupling with ethynyl magnesium halide under the action of a metal catalyst, and adding with water through acid catalysis to finally obtain a product, namely the 2,4, 6-trichlorophenyl substituted acetone. The method has the advantages of more raw material sources, obvious cost advantage, safer and more convenient preparation method, high total yield and less three wastes, and is favorable for industrialization.
Description
Technical Field
The invention relates to a preparation method of 2,4, 6-trichlorophenyl substituted acetone, in particular to a method for preparing 2,4, 6-trichlorophenyl substituted acetone by halogenating 2,4, 6-trichlorotoluene, coupling with a metal-catalyzed Grignard reagent and adding acetylene water by acid catalysis.
Background
2,4, 6-trichlorophenyl substituted acetone is commonly used in the synthesis of medicines and pesticides, and particularly, as an intermediate of fluxapyroxad serving as a bactericide, many people pay attention to and research, and the synthesis methods reported in the literature mainly comprise two methods: the first method is to take 2,4, 6-trichlorobenzaldehyde as a raw material, condense the trichlorobenzaldehyde with nitroethane and reduce the iron powder to obtain a target product, wherein the 2,4, 6-trichlorobenzaldehyde raw material has high price and less goods sources, and simultaneously a large amount of iron mud is generated during the reduction of the iron powder to cause environmental pollution, and more three wastes are difficult to be discharged to the production stage; the second method is to use 2,4, 6-trichloroaniline as a raw material to prepare a target product through diazotization reaction and acetate propylene ester reaction, and has high diazotization reaction safety risk and low reaction yield, so that the problems of safety and cost are difficult to release to the production stage.
Disclosure of Invention
The invention aims to provide a preparation method of 2,4, 6-trichlorophenyl substituted acetone aiming at the defects in the prior art.
The technical scheme for realizing the purpose of the invention is as follows: a preparation method of 2,4, 6-trichlorophenyl substituted acetone comprises the following steps:
s1, adding 2,4, 6-trichlorotoluene and a chlorinating agent into an organic solvent at a certain temperature for chlorination reaction to obtain 2,4, 6-trichlorobenzyl chloride;
s2, adding the 2,4, 6-trichlorobenzyl chloride obtained by the reaction into an organic solvent at a certain temperature, and carrying out coupling reaction with ethynyl magnesium halide under the action of a nickel catalyst to obtain 2,4, 6-trichlorophenyl propyne;
s3, adding the 2,4, 6-trichlorophenyl propyne obtained by the reaction into an organic solvent at a certain temperature, and carrying out addition reaction with water under the action of an acid catalyst to obtain 2,4, 6-trichlorophenyl substituted acetone;
reaction formula is
Wherein, X is one of Cl, Br and I.
The technical scheme specifically comprises the following steps:
s1, sequentially adding an organic solvent, 2,4, 6-trichlorotoluene and a halogenating reagent into a first reaction vessel under the protection of nitrogen, stirring uniformly, and then heating to a certain temperature; keeping the temperature at the temperature until the normalized content of the 2,4, 6-trichlorotoluene in the total material is less than 1 percent; heating and distilling to obtain 2,4, 6-trichlorobenzyl chloride for later use;
s2, adding an organic solvent, 2,4, 6-trichlorobenzyl chloride and a metal catalyst into a second reaction vessel at normal temperature, cooling to a certain temperature, and dropwise adding ethynyl magnesium halide while stirring; keeping the temperature at the temperature until the normalized content of the 2,4, 6-trichloro benzyl chloride in the total material is less than 1 percent; acidifying, separating, desolventizing, post-treating and distilling to obtain 2,4, 6-trichlorophenyl propyne;
s3, adding an organic solvent, 2,4, 6-trichlorophenyl propyne, an acid catalyst and water into a third reaction container at normal temperature, heating to a certain temperature, and keeping the temperature until the normalized content of the 2,4, 6-trichlorophenyl propyne in the total material is less than 1% by liquid chromatography; acidifying, separating liquid, desolventizing, post-treating and distilling to obtain the 2,4, 6-trichlorophenyl substituted acetone.
In the above technical solution S1, the molar ratio of the 2,4, 6-trichlorotoluene to the halogenating agent is 1: 1-10; the molar ratio of the using amount of the organic solvent to the 2,4, 6-trichlorotoluene is 1: 1-10;
in S2, the molar ratio of the 2,4, 6-trichlorobenzyl chloride to the ethynyl magnesium halide is 1: 1-10; the molar ratio of the dosage of the organic solvent to the 2,4, 6-trichlorobenzyl chloride is 1: 1-10; the molar ratio of the dosage of the metal catalyst to the 2,4, 6-trichlorobenzyl chloride is 1: 10-1000 parts;
in S3, the molar ratio of the 2,4, 6-trichlorophenyl propyne to water is 1: 1-10; the molar ratio of the amount of the organic solvent to the 2,4, 6-trichlorophenyl propyne is 1: 1-10; the molar ratio of the used amount of the acid catalyst to the 2,4, 6-trichlorophenyl propyne is 1: 10-1000.
In the technical schemes S1, S2 and S3, the certain temperature is-20-150 ℃.
In the above technical solutions S1, S2, and S3, the organic solvent is one of a halogenated hydrocarbon solvent, an aromatic solvent, an ether solvent, an ester solvent, an alcohol solvent, and a strong polar solvent containing a heteroatom.
In the above technical solution S1, the halogenating agent is one of thionyl chloride, NCS, chlorine, NBS, bromine, dichlorohydantoin, dibromohydantoin, NIS, elemental iodine, copper chloride, and copper bromide.
In the above technical solution S2, the catalyst is one of hydrous nickel chloride, anhydrous nickel chloride, nickel acetate, nickel sulfate, nickel acetylacetonate, triphenyl phosphorus nickel chloride, cuprous chloride, ferrous chloride, and ferrous sulfate.
In the above technical scheme S3, the acid catalyst is one of sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, acetic acid, hydrochloric acid, and formic acid.
In the technical scheme, the halogenated hydrocarbon solvent is one of dichloromethane, dichloroethane and chloroform, the aromatic solvent is one of chlorobenzene, toluene and xylene, the ether solvent is tetrahydrofuran, the ester solvent is one of methyl acetate and ethyl acetate, the alcohol solvent is one of methanol, ethanol and isopropanol, and the strong polar solvent containing hetero atoms is one of DMF, DMA, DMSO, NMP, sulfolane and DMI.
In the technical schemes S1 and S3, the certain temperature is 60-100 ℃; in S2, the certain temperature is-20 ℃.
After the technical scheme is adopted, the invention has the following positive effects:
the method comprises the steps of adding 2,4, 6-trichlorotoluene and a chlorination reagent into an organic solvent at a certain temperature to prepare 2,4, 6-trichlorophenyl benzyl chloride, coupling the trichlorophenyl benzyl chloride with ethynyl magnesium halide under the action of a metal catalyst, and adding the coupled product with water under the action of acid catalysis to finally obtain the product 2,4, 6-trichlorophenyl substituted acetone. The method has the advantages of more raw material sources, obvious cost advantage, safer and more convenient preparation method, high total yield and less three wastes, and is favorable for industrialization.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments.
Example 1 2,4, 6-trichlorophenyl-substituted propanones
Preparing a target product in a small trial:
200mL of dichloroethane, 0.2mol of 2, 3, 6-trichlorotoluene and 0.22mol of NBS are sequentially added into a 500mL four-neck flask with a condenser under the protection of nitrogen, the mixture is stirred uniformly and then slowly heated to 80 ℃, then the temperature is maintained until the normalized content of the 2, 3, 6-trichlorotoluene liquid phase chromatogram in the material is less than 1%, dichloroethane is recovered by desolventizing (the recovery rate is 95%), 250mL of water is added into the residue, liquid separation is carried out by stirring, and the organic layer is distilled to obtain the target 2, 3, 6-trichlorobenzyl bromide with the content of more than 98%, and the yield is 92%.
200mL of THF, 0.2mol of 2, 3, 6-trichlorobenzyl bromide and 0.005mol of anhydrous nickel chloride are sequentially added into a 500mL four-neck flask with a condenser under the protection of nitrogen, the mixture is uniformly stirred and cooled to 0 ℃, then 0.21mol of ethynyl magnesium bromide THF solution is dropwise added, the temperature is kept until the normalized content of the 2, 3, 6-trichlorobenzyl bromide in the material is less than 1 percent after the dropwise addition, THF (recovery rate of 94 percent) is recovered by desolventizing, 250mL of 10 percent of hydrochloric acid aqueous solution is added into the residue, the mixture is stirred, separated and the organic layer is distilled to obtain the target 2,4, 6-trichlorophenyl propyne with the content of more than 95 percent, and the yield is 98 percent.
Example 2 substitution of 2,4, 6-trichlorophenyl acetone
Preparing a target product in a trial mode:
1500L of dichloroethane, 390kg of 2, 3, 6-trichlorotoluene and 390kg of NBS are sequentially pumped into a 3000L enamel kettle provided with a graphite condenser under the protection of nitrogen, the temperature is slowly raised to 80 ℃ after uniform stirring, then the temperature is kept until the normalized content of the 2, 3, 6-trichlorotoluene liquid chromatogram in the material is less than 1%, dichloroethane is recovered by desolventizing (the recovery rate is 95%), 1000L of water is added into the remainder, the mixture is stirred and separated, and the organic layer is distilled to obtain 490kg of the target 2, 3, 6-trichlorobenzyl bromide with the content of more than 98%, and the yield is 90%.
Pumping 1000LTHF, 540kg2, 3, 6-trichlorobenzyl bromide and 650g anhydrous nickel chloride into a 5000l enamel kettle equipped with a graphite condenser in sequence under the protection of nitrogen, cooling to 0 ℃ after uniformly stirring, then dropwise adding 268kg acetenyl magnesium bromide THF solution, preserving heat until the normalized content of 2, 3, 6-trichlorobenzyl bromide in the material is less than 1% after the dropwise adding is finished, desolventizing and recovering THF (recovery rate is 90%), adding 250mL 10% hydrochloric acid aqueous solution into the residue, stirring, separating liquid, distilling an organic layer to obtain 430kg2,4, 6-trichlorophenyl propyne with the content of 96% as a target substance, wherein the yield is 90%.
1000L of toluene, 10L of water, 430kg of 2,4, 6-trichlorophenyl propyne and 500g of sulfuric acid are sequentially added into a 2000L enamel kettle equipped with a graphite condenser under the protection of nitrogen, the mixture is uniformly stirred, the temperature is raised to 80 ℃, the temperature is maintained until the liquid chromatography normalization content of the 2,4, 6-trichlorophenyl propyne in the material is less than 1%, toluene is recovered by desolvation (the recovery rate is 93%), 500mL of water is added into the residue, the pH value is adjusted to be 7, liquid separation is carried out, the organic layer is distilled to obtain 410kg of target 2,4, 6-trichlorophenyl substituted acetone with the content of more than 98%, and the yield is 88%.
Example 3 substitution of 2,4, 6-trichlorophenyl acetone
Preparing a target product in a small trial:
the optimized partial results of the first-step halogenation parallel reaction for the halogenating agent are as follows:
| serial number | Halogenating agents | Solvent(s) | Yield of |
| 1 | Thionyl chloride | Chlorobenzene | 54％ |
| 2 | NCS | Dichloroethane | 83％ |
| 3 | Chlorine gas | Chloroform | 88％ |
| 4 | Bromine compound | Benzene and its derivatives | 90％ |
The results of the parallel optimization part of the second coupling reaction aiming at the metal catalyst are as follows:
| serial number | Catalyst and process for producing the same | Yield of |
| 1 | Ferrous chloride | 92％ |
| 2 | Cuprous bromide | 53％ |
| 3 | Triphenylphosphonium nickel chloride | 95％ |
| 4 | Nickel sulfate | 88％ |
The results of the third step of parallel optimization of the water addition reaction on the acid catalyst are as follows:
| serial number | Acid(s) | Solvent(s) | Yield of |
| 1 | Sulfuric acid | Chlorobenzene | 95％ |
| 2 | Sulfuric acid | Toluene | 90％ |
| 3 | Para toluene sulfonic acid | Toluene | 87％ |
| 4 | Trifluoromethanesulfonic acid | Toluene | 76％ |
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A preparation method of 2,4, 6-trichlorophenyl substituted acetone is characterized by comprising the following steps:
s1, adding 2,4, 6-trichlorotoluene and a chlorinating agent into an organic solvent at a certain temperature for chlorination reaction to obtain 2,4, 6-trichlorobenzyl chloride;
s2, adding the 2,4, 6-trichlorobenzyl chloride obtained by the reaction into an organic solvent at a certain temperature, and carrying out coupling reaction with ethynyl magnesium halide under the action of a nickel catalyst to obtain 2,4, 6-trichlorophenyl propyne;
s3, adding the 2,4, 6-trichlorophenyl propyne obtained by the reaction into an organic solvent at a certain temperature, and carrying out addition reaction with water under the action of an acid catalyst to obtain 2,4, 6-trichlorophenyl substituted acetone;
reaction formula is
Wherein, X is one of Cl, Br and I.
2. The method for preparing 2,4, 6-trichlorophenyl substituted acetone as claimed in claim 1, includes the following steps:
s1, sequentially adding an organic solvent, 2,4, 6-trichlorotoluene and a halogenating reagent into a first reaction vessel under the protection of nitrogen, stirring uniformly, and then heating to a certain temperature; keeping the temperature at the temperature until the normalized content of the 2,4, 6-trichlorotoluene in the total material is less than 1 percent; heating and distilling to obtain 2,4, 6-trichlorobenzyl chloride for later use;
s2, adding an organic solvent, 2,4, 6-trichlorobenzyl chloride and a metal catalyst into a second reaction vessel at normal temperature, cooling to a certain temperature, and dropwise adding ethynyl magnesium halide while stirring; keeping the temperature at the temperature until the normalized content of the 2,4, 6-trichloro benzyl chloride in the total material is less than 1 percent; acidifying, separating, desolventizing, post-treating and distilling to obtain 2,4, 6-trichlorophenyl propyne;
s3, adding an organic solvent, 2,4, 6-trichlorophenyl propyne, an acid catalyst and water into a third reaction container at normal temperature, heating to a certain temperature, and keeping the temperature until the normalized content of the 2,4, 6-trichlorophenyl propyne in the total material is less than 1% by liquid chromatography; acidifying, separating liquid, desolventizing, post-treating and distilling to obtain the 2,4, 6-trichlorophenyl substituted acetone.
3. The process according to claim 2, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps:
in S1, the molar ratio of the 2,4, 6-trichlorotoluene to the halogenating agent is 1: 1-10; the molar ratio of the use amount of the organic solvent to the 2,4, 6-trichlorotoluene is 1: 1-10;
in S2, the molar ratio of the 2,4, 6-trichlorobenzyl chloride to the ethynyl magnesium halide is 1: 1-10; the molar ratio of the dosage of the organic solvent to the 2,4, 6-trichlorobenzyl chloride is 1: 1-10; the molar ratio of the metal catalyst to the 2,4, 6-trichlorobenzyl chloride is 1: 10-1000 parts;
in S3, the molar ratio of the 2,4, 6-trichlorophenyl propyne to water is 1: 1-10; the molar ratio of the amount of the organic solvent to the 2,4, 6-trichlorophenyl propyne is 1: 1-10; the molar ratio of the used amount of the acid catalyst to the 2,4, 6-trichlorophenyl propyne is 1: 10-1000.
4. The process according to claim 2, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: the certain temperature is-20 to 150 ℃ in S1, S2 and S3.
5. The process according to claim 2, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: in S1, S2, and S3, the organic solvent is one of a halogenated hydrocarbon solvent, an aromatic solvent, an ether solvent, an ester solvent, an alcohol solvent, and a strong polar solvent containing a hetero atom.
6. The process according to claim 2, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: in S1, the halogenating agent is one of thionyl chloride, NCS, chlorine, NBS, bromine, dichlorohydantoin, dibromohydantoin, NIS, elemental iodine, copper chloride, and copper bromide.
7. The process according to claim 2, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: in S2, the catalyst is one of hydrous nickel chloride, anhydrous nickel chloride, nickel acetate, nickel sulfate, nickel acetylacetonate, triphenyl phosphorus nickel chloride, cuprous chloride, ferrous chloride and ferrous sulfate.
8. The process according to claim 2, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: in S3, the acid catalyst is one of sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, acetic acid, hydrochloric acid, and formic acid.
9. The process according to claim 5, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: the halogenated hydrocarbon solvent is one of dichloromethane, dichloroethane and chloroform, the aromatic solvent is one of chlorobenzene, toluene and xylene, the ether solvent is tetrahydrofuran, the ester solvent is one of methyl acetate and ethyl acetate, the alcohol solvent is one of methanol, ethanol and isopropanol, and the strong polar solvent containing hetero atoms is one of DMF, DMA, DMSO, NMP, sulfolane and DMI.
10. The process according to claim 4, wherein the acetone substituted by 2,4, 6-trichlorophenyl group is prepared by the following steps: in S1 and S3, the certain temperature is 60-100 ℃; in S2, the certain temperature is-20 to 20 ℃.
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| CN102239137A (en) * | 2008-12-05 | 2011-11-09 | 先正达参股股份有限公司 | Novel pyrazole-4 -n-alkoxycarboxamides as microbiocides |
| CN104136409A (en) * | 2012-02-28 | 2014-11-05 | 先正达参股股份有限公司 | Process for the preparation of substituted phenylpropanones |
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| CN102239137A (en) * | 2008-12-05 | 2011-11-09 | 先正达参股股份有限公司 | Novel pyrazole-4 -n-alkoxycarboxamides as microbiocides |
| CN104136409A (en) * | 2012-02-28 | 2014-11-05 | 先正达参股股份有限公司 | Process for the preparation of substituted phenylpropanones |
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