CN112778108A - Synthesis method of 4-substituted cyclohexanone - Google Patents

Synthesis method of 4-substituted cyclohexanone Download PDF

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CN112778108A
CN112778108A CN202110048162.2A CN202110048162A CN112778108A CN 112778108 A CN112778108 A CN 112778108A CN 202110048162 A CN202110048162 A CN 202110048162A CN 112778108 A CN112778108 A CN 112778108A
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catalyst
compound
acid
formula
raney
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刘显伟
童国通
马青松
刘娇
陈芳
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Huize Chemical Technology Puyang Co ltd
Hangzhou Vocational and Technical College
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Huize Chemical Technology Puyang Co ltd
Hangzhou Vocational and Technical College
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/27—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation
    • C07C45/32—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen
    • C07C45/37—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of >C—O—functional groups to >C=O groups
    • C07C45/38—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of >C—O—functional groups to >C=O groups being a primary hydroxyl group
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
    • C07C41/01—Preparation of ethers
    • C07C41/18—Preparation of ethers by reactions not forming ether-oxygen bonds
    • C07C41/20—Preparation of ethers by reactions not forming ether-oxygen bonds by hydrogenation of carbon-to-carbon double or triple bonds

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  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

The invention discloses a method for synthesizing 4-substituted cyclohexyl ketone, which comprises the following steps: 4-substituent phenol compounds are used as raw materials, 4-substituent phenol is catalyzed and hydrogenated to obtain 4-substituent cyclohexanol, and then oxygen-containing gas is used as an oxidant to oxidize the 4-substituent cyclohexanol to prepare the 4-substituent cyclohexanone. The method uses oxygen-containing gas as an oxidant, has low price, good reaction selectivity and high oxidation reaction yield, is environment-friendly, and is an ideal clean oxidant; in addition, the whole synthesis process is simple, mild in condition, simple in post-treatment, green and environment-friendly, and suitable for large-scale industrial production.

Description

Synthesis method of 4-substituted cyclohexanone
Technical Field
The invention relates to the field of organic synthesis, in particular to a synthesis method of 4-substituted cyclohexanone.
Background
The 4-substituted cyclohexanone is an important intermediate material, not only can be applied to the field of liquid crystal materials, but also can be applied to the fields of medicines and pesticides, for example, the 4-methoxycyclohexanone is an important intermediate for synthesizing the spirotetramat serving as an insecticide.
At present, the synthesis methods of 4-methoxycyclohexanone comprise a traditional synthesis method, a 4-methoxyphenol catalytic hydrogenation method and a 4-methoxycyclohexanol oxidation method. In the traditional synthesis method, 1, 4-cyclohexanedione-ethylene ketal is used as a starting material, and the 4-methoxycyclohexanone is synthesized through the steps of reduction, methylation, protecting group removal and the like. The route has the defects of complex process, low methylation reaction yield and the like, and is not suitable for large-scale industrial production.
The 4-methoxyphenol catalytic hydrogenation method is that 4-methoxyphenol is directly subjected to one-step method to generate 4-methoxycyclohexanone under the catalytic action. The conversion rate of the 4-methoxyphenol is 33.2 percent by carrying out aqueous phase hydrogenation on the 4-methoxyphenol by using Pd/C as a catalyst and sodium formate under the microwave irradiation by using ZHao (New J Chem,2012,36(4): 1085-1090) and the like. The disadvantage of this process is the excessively low conversion of the starting materials. Patent US20130165697A uses 4-methoxyphenol as raw material and Pd/C as catalyst, and the yield of 4-methoxycyclohexanone reaches 93%, but the catalyst dosage in this method is large, and the catalyst cannot be reused, and the production cost is high.
The 4-methoxycyclohexanol oxidation method is to oxidize alcohol compounds into ketone, and commonly used oxidants are chromate, manganese oxide, ruthenium oxide, and the like. The method uses expensive oxidant and produces by-product with great environmental pollution. Zhang Jian Gong et al (China Agrochemicals,2012,8(4):32-35.) adopt Jones reagent prepared from chromium trioxide and concentrated sulfuric acid to oxidize 4-methoxycyclohexanol to obtain 4-methoxycyclohexanone, wherein the yield is 78%.
Disclosure of Invention
Aiming at the problems that the oxidant in the prior art has high toxicity and high price and can generate a large amount of byproducts to pollute the environment, the 4-substituted cyclohexanol is obtained by hydrogenating 4-substituted phenol, and then the 4-substituted cyclohexanone is prepared by oxidizing the 4-substituted cyclohexanol by taking oxygen-containing gas as the oxidant, so that the yield is high and the method is environment-friendly.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a method of synthesizing a 4-substituted cyclohexanone, comprising:
(1) carrying out catalytic hydrogenation reaction on the compound of the formula (I) to generate a compound of a formula (II);
(2) in an organic solvent, the compound of the formula (II) obtained in the step (1) and oxygen-containing gas are subjected to oxidation reaction under the action of a catalytic system to obtain a compound of the formula (III).
The reaction formula is as follows:
Figure BDA0002898032450000021
r is selected from C1-6 alkyl, trifluoroalkyl or phenyl. Preferably, R is selected from one of methyl, ethyl, isopropyl, trifluoromethyl, trifluoroethyl, and phenyl.
The catalytic system comprises a catalyst A, a catalyst B and a catalyst C.
The structural formula of the catalyst A is at least one of the following formulas:
Figure BDA0002898032450000022
Figure BDA0002898032450000031
the catalyst B is one or the combination of more of nitric oxide, nitrogen dioxide, sodium nitrite, potassium nitrite and nitrous acid ester;
the catalyst C is one or a combination of more of bromide, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, hydrobromic acid, hydrofluoric acid, hydroiodic acid, methanesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, sodium bisulfate, potassium bisulfate and sodium dihydrogen phosphate.
The oxygen-containing gas is oxygen or air.
The amount of the catalyst A is 0.1-10%, preferably 1-5% of the amount of the 4-substituted cyclohexanol compound; the amount of the catalyst B is 0.1-10%, preferably 0.5-2% of the amount of the 4-substituted cyclohexanol compound; the catalyst C is used in an amount of 0.1 to 10%, preferably 1 to 5%, based on the amount of the 4-substituted cyclohexanol-based compound.
The temperature of the oxidation reaction is 0 to 100 ℃, preferably 0 to 50 ℃.
The solvent is one or the combination of more of dichloromethane, dichloroethane, toluene, xylene, chlorobenzene, chloroform, fluorobenzene and trifluorotoluene.
The oxidation time is 0.5-24h, preferably 1-6 h.
Further, in the step (1), the compound of the formula (I) and hydrogen are subjected to hydrogenation reaction in an organic solvent under the action of a hydrogenation catalyst to obtain a compound of the formula (II).
The hydrogenation catalyst is a Raney type catalyst and/or a transition metal supported catalyst; the Raney type catalyst is preferably one or the combination of more of Raney nickel, Raney cobalt, Raney palladium and Raney copper; the transition metal supported catalyst is preferably one or more of palladium/carbon, platinum/carbon, ruthenium/carbon, nickel/alumina, platinum/alumina, palladium/ferroferric oxide, nickel-copper/alumina, rhodium/silica and platinum-rhodium/alumina.
The pressure of the hydrogen is 1-8MPa, and the temperature of the hydrogenation reaction is preferably 50-150 ℃.
The organic solvent is selected from methanol, ethanol, propanol or isopropanol.
The term "C1-6 alkyl" refers to a straight or branched chain saturated hydrocarbon radical containing from 1 to 6 carbon atoms. C1-6 alkyl includes, but is not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl.
The term "alkyl" in the term "trifluoroalkyl" is a straight or branched chain saturated hydrocarbon group containing 1 to 6 carbon atoms.
Compared with the prior art, the invention has the beneficial effects that:
the method uses oxygen-containing gas as an oxidant, has low price, good reaction selectivity and high oxidation reaction yield, is environment-friendly, and is an ideal clean oxidant; in addition, the whole synthesis process is simple, mild in condition, simple in post-treatment, green and environment-friendly, and suitable for large-scale industrial production.
Detailed Description
The invention is further illustrated, but not limited, by the following specific examples.
Example 1:
adding 12.4g of 4-methoxyphenol, 1.1g of Raney-Ni catalyst and 150mL of isopropanol into a 500mL high-pressure kettle, sealing the high-pressure kettle, introducing nitrogen, replacing air in the kettle for three times, introducing hydrogen, adding to a required pressure, checking to ensure that the reaction kettle is airtight, then introducing hydrogen for emptying, repeating for three times, stirring, heating to 150 ℃, maintaining the hydrogen pressure at 5MPa, reacting for 6 hours, stopping the reaction, cooling, emptying hydrogen, extracting reaction liquid in the kettle, filtering to remove the catalyst, and carrying out reduced pressure distillation and concentration to obtain 12.3g of white solid, namely 4-methoxycyclohexanol with the yield of 94.5%;
13.0g of 4-methoxycyclohexanol was added to a 500mL autoclave and dissolved in 150mL of toluene, then 0.2g of catalyst (shown in formula 15), 0.2mL of acetic acid (30 wt% solution), and 0.03g of sodium nitrite were added to obtain a raw material mixture, the mixture was stirred in air at 50 ℃ for 1 hour, after the reaction was completed, water was washed to separate an organic phase, and after drying with anhydrous sodium sulfate, the organic solvent was distilled off to obtain 12.1g of white solid 4-methoxycyclohexanone, with a yield of 94.4%.
1H NMR(DMSO)δ＝3.58(m,1H),3.30(s,3H),2.34(m,2H),2.20(m,2H),1.91(m,4H).
Example 2:
adding 15.2g of 4-isopropoxyphenol, 1.5g of ruthenium/carbon catalyst and 150mL of ethanol into a 500mL high-pressure kettle, sealing the high-pressure kettle, introducing hydrogen to evacuate, introducing nitrogen to replace air in the kettle for three times, repeating the steps for three times, introducing hydrogen, adding the mixture to a required pressure, testing to ensure that the reaction kettle is airtight, stirring, heating to 70 ℃, maintaining the hydrogen pressure at 5MPa, reacting for 8 hours, stopping the reaction, cooling, slowly discharging the evacuated hydrogen to the maximum, turning off the stirring, extracting reaction liquid in the kettle, filtering to remove the catalyst, and carrying out reduced pressure distillation and concentration to obtain 15.5g of white solid, namely 4-isopropoxycyclohexanol with the yield of 98.0%;
15.8g of 4-isopropoxycyclohexanol was charged into a 500mL autoclave and dissolved in 150mL of methylene chloride, then 0.5g of a catalyst (represented by formula 1), 0.5mL of hydrochloric acid (25 wt% solution), and 0.09g of potassium nitrite were added, followed by continuously introducing oxygen at 1MPa, stirring and reacting at 30 ℃ for 3 hours, washing with water after the reaction was completed, separating an organic phase, drying over night with anhydrous sodium sulfate, and distilling off the organic solvent to obtain 14.8g of colorless solid 4-isopropoxycyclohexanone in a yield of 94.7%.
1HNMR(CDCl3)δ＝3.78(m,1H),3.72(m,1H),2.57(m,2H),2.24(m,2H),1.99(dd,2H),1.92(m,2H),1.17(d,6H).
Example 3: the "catalyst 15" in the step (2) of example 1 was replaced with "catalyst 2" and "sodium nitrite" was replaced with "ethyl nitrite" to obtain 4-methoxycyclohexanone in a yield of 93.8% as in example 1.
The nuclear magnetic data were as in example 1.
Example 4: the acetic acid obtained in the step (2) of example 1 was replaced by methanesulfonic acid, and the reaction time "1 h" was replaced by "5 h", to obtain 4-methoxycyclohexanone, which was otherwise identical to example 1, in a yield of 94.1%.
The nuclear magnetic data were as in example 1.
Example 5: the procedure of (2) in example 2 was repeated except that "catalyst 1" was replaced with "catalyst 13" and "hydrochloric acid" was replaced with "sodium hydrogensulfate" to obtain 4-isopropoxycyclohexanone in a yield of 93.1% as in example 1.
The nuclear magnetic data were as in example 2.
Example 6: the reaction temperature was changed from "30 ℃ to" 40 ℃ "in the step (2) of example 2 to" nitric oxide ", to give 4-isopropoxycyclohexanone in a yield of 93.7% as in example 1.
The nuclear magnetic data were as in example 2.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the invention is not limited to the embodiments described above, which are described in the specification only to illustrate the principles of the invention. The invention also includes various insubstantial changes and modifications within the spirit of the invention, as claimed by those skilled in the art.

Claims (10)

1. A method of synthesizing a 4-substituted cyclohexanone, comprising:
(1) carrying out catalytic hydrogenation reaction on the compound of the formula (I) to generate a compound of a formula (II);
(2) in an organic solvent, carrying out an oxidation reaction on the compound of the formula (II) obtained in the step (1) and oxygen-containing gas under the action of a catalytic system to obtain a compound of a formula (III);
the structural formulas of the compound of formula (I), the compound of formula (II) and the compound of formula (III) are as follows:
Figure FDA0002898032440000011
r is selected from C1-6 alkyl, trifluoroalkyl or phenyl; preferably, R is selected from one of methyl, ethyl, isopropyl, trifluoromethyl, trifluoroethyl, and phenyl.
2. The method of claim 1, wherein the oxygen-containing gas is oxygen or air.
3. The process according to claim 1 or 2, characterized in that the catalytic system is a system comprising catalyst a, catalyst B, catalyst C; the structural formula of the catalyst A is at least one of the following formulas:
Figure FDA0002898032440000012
Figure FDA0002898032440000021
the catalyst B is one or the combination of more of nitric oxide, nitrogen dioxide, sodium nitrite, potassium nitrite and nitrous acid ester;
the catalyst C is one or a combination of more of bromide, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, hydrobromic acid, hydrofluoric acid, hydroiodic acid, methanesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, sodium bisulfate, potassium bisulfate and sodium dihydrogen phosphate.
4. The process according to claim 3, characterized in that the catalyst A is used in an amount of 0.1-10%, preferably 1-5%, of the amount of the substance of the 4-substituted cyclohexanol type; the amount of the catalyst B is 0.1-10%, preferably 0.5-2% of the amount of the 4-substituted cyclohexanol compound; the catalyst C is used in an amount of 0.1 to 10%, preferably 1 to 5%, based on the amount of the 4-substituted cyclohexanol-based compound.
5. The process according to claim 1, characterized in that the temperature of the oxidation reaction is between 0 and 100 ℃, preferably between 0 and 50 ℃.
6. The process according to claim 1, characterized in that the organic solvent is a combination of one or more of dichloromethane, dichloroethane, toluene, xylene, chlorobenzene, chloroform, fluorobenzene, trifluorotoluene.
7. The method according to claim 1, wherein the compound of formula (I) is hydrogenated with hydrogen in an organic solvent under the action of a hydrogenation catalyst to obtain the compound of formula (II).
8. The process according to claim 7, characterized in that the hydrogenation catalyst is a Raney-type catalyst and/or a transition metal supported catalyst; the Raney type catalyst is preferably one or the combination of more of Raney nickel, Raney cobalt, Raney palladium and Raney copper; the transition metal supported catalyst is preferably one or more of palladium/carbon, platinum/carbon, ruthenium/carbon, nickel/alumina, platinum/alumina, palladium/ferroferric oxide, nickel-copper/alumina, rhodium/silica and platinum-rhodium/alumina.
9. The process according to claim 7, characterized in that the pressure of the hydrogen is between 1 and 8MPa and the temperature of the hydrogenation reaction is preferably between 50 and 150 ℃.
10. The method according to claim 7, characterized in that the organic solvent is selected from methanol, ethanol, propanol or isopropanol.
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Application publication date: 20210511