阅读说明：本技术 一种邻位环己二酮的合成方法 (Synthesis method of ortho-cyclohexanedione ) 是由 汤须崇 谢清萍 曹丽平 宋航 于 2021-10-28 设计创作，主要内容包括：本发明涉及有机合成技术领域,提供了一种邻位环己二酮的合成方法,本发明提供的方法采用三甲基硅烷基对环己酮中的羰基进行保护,然后通过氧化反应在邻位引入羰基基团,再通过脱硅将三甲基硅烷基脱除,最后通过催化氧化反应将羟基氧化为羰基,从而得到邻位环己二酮。本发明提供的方法不仅能够保护羰基,还提高了产物的选择性；并且本发明使用的原料廉价易得,无需使用有毒有害试剂,安全性好,反应过程中无有毒有害气体产生,对环境友好；另外,本发明提供的方法操作简单,副产物少,产品纯度高,具有较高的经济效益,适合工业化生产。(The invention relates to the technical field of organic synthesis, and provides a method for synthesizing vicinal cyclohexanedione. The method provided by the invention can protect carbonyl and improve the selectivity of the product; the raw materials used in the invention are cheap and easy to obtain, no toxic or harmful reagent is needed, the safety is good, no toxic or harmful gas is generated in the reaction process, and the method is environment-friendly; in addition, the method provided by the invention is simple to operate, few in byproducts, high in product purity, higher in economic benefit and suitable for industrial production.)

1. A method for synthesizing orthocyclohexanedione is characterized by comprising the following steps:

(1) mixing cyclohexanone, trimethylchlorosilane, an alkaline agent and a catalyst to perform a silicon enol etherification reaction to obtain a compound with a structure shown in a formula I;

(2) mixing the compound with the structure shown in the formula I and m-chloroperoxybenzoic acid for oxidation reaction to obtain a compound with the structure shown in the formula II;

(3) mixing the compound with the structure shown in the formula II and a desilication reagent for desilication reaction to obtain a compound with the structure shown in the formula III;

(4) mixing the compound with the structure shown in the formula III, a catalyst and an oxidant for catalytic oxidation reaction to obtain ortho-cyclohexanedione;

2. the synthesis method of claim 1, wherein the alkaline agent is one or more of potassium carbonate, sodium hydroxide, potassium hydroxide, triethylamine and pyridine;

the catalyst in the step (1) is one or more of potassium iodide, sodium iodide, iodine simple substance, sodium methoxide, potassium tert-butoxide and triethylamine;

the solvent for the enol silicon etherification reaction is one or more of toluene, dioxane, N-dimethylformamide, dimethyl sulfoxide and tetrahydrofuran.

3. The synthesis method according to claim 1 or 2, wherein the molar ratio of the cyclohexanone to the trimethylchlorosilane is 1 (1-3); the dosage of the catalyst in the step (1) is 1-10% of the weight of cyclohexanone; the dosage of the alkaline agent is 50-200% of the weight of the cyclohexanone.

4. The synthesis method according to claim 1 or 2, wherein the temperature of the enolic silicoetherification reaction is 50 to 100 ℃ and the time is 2 to 10 hours.

5. The synthesis method according to claim 1, wherein the molar ratio of the compound having the structure shown in formula I to m-chloroperoxybenzoic acid is (1-4): 1;

the solvent for oxidation reaction is one or more of cyclohexane, cyclopentane, n-hexane or petroleum ether.

6. The synthesis method according to claim 1 or 5, wherein the temperature of the oxidation reaction is-20 to 0 ℃ and the time is 1 to 5 hours.

7. The synthesis method according to claim 1, wherein the desiliconization reagent is one or more of potassium fluoride, sodium fluoride, calcium fluoride and hydrofluoric acid; the molar ratio of the compound with the structure shown in the formula II to the desiliconization reagent is 1 (1-5);

the solvent for the desilication reaction is one or more of dichloromethane, chloroform, methanol, ethanol, acetonitrile and tetrahydrofuran.

8. The synthesis method according to claim 1 or 7, wherein the desilication reaction is carried out at a temperature of 20-40 ℃ for 1-4 hours.

9. The synthesis method according to claim 1, wherein the catalyst in the step (4) is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium acetate and triethylamine;

the oxidant is any one of phosphorus pentoxide, dimethyl sulfoxide (DMSO), ferric chloride or manganese dioxide;

the solvent for catalytic oxidation reaction is one or more of dichloromethane, N-dimethylformamide, dimethyl sulfoxide and tetrahydrofuran.

10. The synthesis method of claim 1, wherein the molar ratio of the compound having the structure shown in formula III to the oxidant is 1 (1-4); the dosage of the catalyst in the step (4) is 20-80% of the weight of the compound with the structure shown in the formula III;

the temperature of the catalytic oxidation reaction is-5 ℃, and the time is 0.5-6 h.

Technical Field

The invention relates to the technical field of organic synthesis, in particular to a method for synthesizing vicinal cyclohexanedione.

Background

The vicinal cyclohexanedione is an important chemical raw material, can be used for synthesizing fine chemicals such as spices and medicines, and can also be used as an organic chemical solvent. The orthocyclohexanedione is mainly prepared by oxidizing cyclohexanone, and at present, the following synthesis methods are mainly adopted:

(1) selenium dioxide oxidation; in 1875, Riley et al reported in Journal of chemical Society Journal "Selenium Dioxide, a new oxidingagent" that Selenium Dioxide was used as an oxidant to oxidize cyclohexanone, the method comprises heating cyclohexanone to 70-80 ℃, then adding a mixed solution of Selenium Dioxide and ethanol dropwise into a bottle, heating and refluxing for 2h after dropwise addition, and finally drying, separating and purifying to obtain the vicinal cyclohexanedione, wherein the yield is 30-50%. The method has simple steps, but the yield is low, and the selenium dioxide has strong toxicity and great harm to human bodies and environment, so the method is not suitable for industrial production.

(2) Oxidation of isoamyl nitrite; in 2014, Wangwei et al published in Zhejiang chemical journal paper "research on preparation of 1, 2-cyclohexanedione by oxidizing cyclohexanone by using isoamyl nitrite", wherein the cyclohexanone is oxidized by using isoamyl nitrite, the method comprises the steps of dissolving the cyclohexanone in sulfuric acid solution, dropwise adding isoamyl nitrite under ice bath condition, reacting for 3h, extracting by using dichloromethane and anhydrous MgSO (MgSO) after the reaction is finished₄And drying, filtering, separating, purifying and rectifying to obtain the ortho-cyclohexanedione, wherein the yield is 60-80%. The method has moderate yield, but the reaction needs a large amount of ether and acid, generates a large amount of waste liquid, has great harm to the environment and is not suitable for industrial production.

(3) Hydrogen peroxide oxidation; in 2020, Nanjing New Material research institute, Inc., China Steel group reports a method for preparing vicinal cyclohexanedione by using hydrogen peroxide as cyclohexanone oxide in patent CN 112441891A, in which cyclohexanone, a catalyst and a ligand are uniformly stirred in a nitrogen atmosphere, hydrogen peroxide is added dropwise at room temperature, after the reaction is finished, water washing and liquid separation are performed, and an organic layer is subjected to reduced pressure rectification to obtain the vicinal cyclohexanedione, wherein the yield is about 95%. The method has high yield, but needs to use a beta-diketoimine ligand which is not easy to obtain, needs self-synthesis, has complex preparation process and is not suitable for large-scale production.

In summary, the existing preparation method of the ortho-cyclohexanedione has the defects of complex preparation steps, high cost and poor environmental protection, and is not suitable for industrial production.

Disclosure of Invention

In view of the above, the present invention provides a method for synthesizing vicinal cyclohexanedione. The method provided by the invention has the advantages of simple steps, low price of raw materials, wide sources, no generation of toxic and harmful waste residues and gases in the reaction process, good environmental protection property, high product yield, higher economic benefit and suitability for industrial production.

In order to achieve the above object, the present invention provides the following technical solutions:

a method for synthesizing orthocyclohexanedione comprises the following steps:

(1) mixing cyclohexanone, trimethylchlorosilane, an alkaline agent and a catalyst to perform a silicon enol etherification reaction to obtain a compound with a structure shown in a formula I;

(2) mixing the compound with the structure shown in the formula I and m-chloroperoxybenzoic acid for oxidation reaction to obtain a compound with the structure shown in the formula II;

(3) mixing the compound with the structure shown in the formula II and a desilication reagent for desilication reaction to obtain a compound with the structure shown in the formula III;

(4) mixing the compound with the structure shown in the formula III, a catalyst and an oxidant for catalytic oxidation reaction to obtain ortho-cyclohexanedione;

preferably, the alkaline agent is one or more of potassium carbonate, sodium hydroxide, potassium hydroxide, triethylamine and pyridine;

the catalyst in the step (1) is one or more of potassium iodide, sodium iodide, iodine simple substance, sodium methoxide, potassium tert-butoxide and triethylamine;

the solvent for the enol silicon etherification reaction is one or more of toluene, dioxane, N-dimethylformamide, dimethyl sulfoxide and tetrahydrofuran.

Preferably, the molar ratio of the cyclohexanone to the trimethylchlorosilane is 1 (1-3); the dosage of the catalyst in the step (1) is 1-10% of the weight of cyclohexanone; the dosage of the alkaline agent is 50-200% of the weight of the cyclohexanone.

Preferably, the temperature of the silyl enol etherification reaction is 50-100 ℃ and the time is 2-10 hours.

Preferably, the molar ratio of the compound with the structure shown in the formula I to m-chloroperoxybenzoic acid is (1-4): 1;

the solvent for oxidation reaction is one or more of cyclohexane, cyclopentane, n-hexane or petroleum ether.

Preferably, the temperature of the oxidation reaction is-20 to 0 ℃, and the time is 1 to 5 hours.

Preferably, the desiliconization reagent is one or more of potassium fluoride, sodium fluoride, calcium fluoride and hydrofluoric acid; the molar ratio of the compound with the structure shown in the formula II to the desiliconization reagent is 1 (1-5);

the solvent for the desilication reaction is one or more of dichloromethane, chloroform, methanol, ethanol, acetonitrile and tetrahydrofuran.

Preferably, the desiliconization reaction is carried out at the temperature of 20-40 ℃ for 1-4 h.

Preferably, the catalyst in the step (4) is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium acetate and triethylamine;

the oxidant is any one of phosphorus pentoxide, dimethyl sulfoxide (DMSO), ferric chloride or manganese dioxide;

the solvent for catalytic oxidation reaction is one or more of dichloromethane, N-dimethylformamide, dimethyl sulfoxide and tetrahydrofuran.

Preferably, the molar ratio of the compound with the structure shown in the formula III to the oxidant is 1 (1-4); the dosage of the catalyst in the step (4) is 20-80% of the weight of the compound with the structure shown in the formula III;

the temperature of the catalytic oxidation reaction is-5 ℃, and the time is 0.5-6 h.

The invention provides a method for synthesizing vicinal cyclohexanedione, which adopts cyclohexanone as a raw material to obtain a final product, namely the vicinal cyclohexanedione, through enol silicon etherification, oxidation, desilication and catalytic oxidation reactions. The method provided by the invention adopts trimethylsilyl to protect carbonyl in cyclohexanone, then introduces carbonyl group at ortho position through oxidation reaction, removes trimethylsilyl through desilication, and finally oxidizes hydroxyl into carbonyl through catalytic oxidation reaction, thereby obtaining ortho-cyclohexanedione. The method provided by the invention can protect carbonyl and improve the selectivity of the product; the raw materials used in the invention are cheap and easy to obtain, no toxic or harmful reagent is needed, the safety is good, no toxic or harmful gas is generated in the reaction process, and the method is environment-friendly; in addition, the method provided by the invention is simple to operate, few in byproducts, high in product purity, higher in economic benefit and suitable for industrial production.

Drawings

FIG. 1 is a gas chromatograph of a compound having the structure shown in formula I prepared in example 1;

FIG. 2 is a gas chromatograph of the compound prepared in example 1 having the structure shown in formula II;

FIG. 3 is a gas chromatograph of a compound prepared in example 1 and having the structure shown in formula III;

FIG. 4 is a drawing showing the preparation of orthocyclohexanedione from example 1¹H-NMR chart.

Detailed Description

The invention provides a synthesis method of ortho-cyclohexanedione, which comprises the following steps:

(1) mixing cyclohexanone, trimethylchlorosilane, an alkaline agent and a catalyst to perform a silicon enol etherification reaction to obtain a compound with a structure shown in a formula I;

(2) mixing the compound with the structure shown in the formula I and m-chloroperoxybenzoic acid for oxidation reaction to obtain a compound with the structure shown in the formula II;

(3) mixing the compound with the structure shown in the formula II and a desilication reagent for desilication reaction to obtain a compound with the structure shown in the formula III;

(4) mixing the compound with the structure shown in the formula III, a catalyst and an oxidant for catalytic oxidation reaction to obtain ortho-cyclohexanedione;

in the invention, the synthesis route of the ortho-cyclohexanedione is shown as a formula A:

the following is a detailed description in conjunction with formula A.

The invention mixes cyclohexanone, trimethylchlorosilane, an alkaline agent and a catalyst to carry out enol silicon etherification reaction to obtain a compound with a structure shown in a formula I. In the invention, the alkaline agent is preferably one or more of potassium carbonate, sodium hydroxide, potassium hydroxide, triethylamine and pyridine; the catalyst for the silicon enol etherification reaction is preferably one or more of potassium iodide, sodium iodide, iodine simple substance, sodium methoxide, potassium tert-butoxide and triethylamine; the preferable solvent for the silicon enol etherification is one or more of toluene, dioxane, N-Dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and tetrahydrofuran.

In the invention, the molar ratio of the cyclohexanone to the trimethylchlorosilane is preferably 1 (1-3), and more preferably 1 (1.5-2.5); the dosage of the catalyst is preferably 1-10% of the weight of cyclohexanone, and more preferably 3-8%; the dosage of the alkaline agent is preferably 50-200% of the weight of cyclohexanone, and preferably 100-150%.

In the invention, the temperature of the enol silicon etherification reaction is preferably 50-100 ℃, more preferably 60-80 ℃, and the time of the enol silicon etherification reaction is preferably 2-10 h, more preferably 3-8 h.

In the specific embodiment of the invention, preferably, cyclohexanone, an alkaline agent, a catalyst and a solvent are mixed firstly, the obtained mixed solution is heated to the temperature of the enolization reaction, then trimethylchlorosilane is dropwise added into the mixed solution, and after the dropwise addition is finished, the heat preservation is carried out for reaction; the time of the enol silicon etherification reaction is counted from the completion of the dropwise addition of the trimethylchlorosilane; in a particular embodiment of the invention, the progress of the reaction is preferably monitored by TLC.

After the enolic silicon etherification reaction is finished, preferably, the obtained product feed liquid is cooled to room temperature, then filtration is carried out, a filter cake is washed by using ether, the obtained filtrate is washed by using 5 wt% of HCl solution, 5% of sodium bicarbonate solution, saturated NaCl solution and distilled water in sequence, and the organic solvent in the washed filtrate is evaporated to dryness to obtain the compound with the structure shown in formula I.

After the compound with the structure shown in the formula I is obtained, the compound with the structure shown in the formula I and m-chloroperoxybenzoic acid (m-CPBA) are mixed for oxidation reaction, and the compound with the structure shown in the formula II is obtained. In the invention, the molar ratio of the compound with the structure shown in the formula I to m-chloroperoxybenzoic acid is preferably (1-4) to 1, more preferably (1.5-3.5) to 1; the solvent for oxidation reaction is preferably one or more of cyclohexane, cyclopentane, n-hexane or petroleum ether.

In the invention, the temperature of the oxidation reaction is preferably-20-0 ℃, more preferably-10-5 ℃, and the time of the oxidation reaction is preferably 1-5 h, more preferably 2-4 h.

In the specific embodiment of the invention, the temperature of the solvent is preferably reduced to the oxidation reaction temperature, then the compound with the structure shown in formula I is added into the solvent, then m-chloroperoxybenzoic acid is added into the feed liquid for a small number of times, after the m-chloroperoxybenzoic acid is added, the reaction is carried out at the oxidation reaction temperature by keeping the temperature, and after the reaction at the oxidation reaction temperature is finished, the reaction is preferably stirred at room temperature for 2 hours, so that the oxidation is more thorough; in the present invention, the mass of m-chloroperoxybenzoic acid added each time is preferably 10 to 30% of the total mass of m-chloroperoxybenzoic acid.

After the oxidation reaction is finished, the invention preferably filters the obtained product liquid, and carries out rotary evaporation on the obtained filtrate to obtain the compound with the structure shown in the formula II.

After the compound with the structure shown in the formula II is obtained, the compound with the structure shown in the formula II and a desiliconization reagent are mixed for desiliconization reaction, and the compound with the structure shown in the formula III is obtained. In the invention, the desiliconization reagent is preferably one or more of potassium fluoride, sodium fluoride, calcium fluoride and hydrofluoric acid; the mol ratio of the compound with the structure shown in the formula II to the desiliconization reagent is preferably 1 (1-5), more preferably 1 (1.1-4), and further preferably 1 (1.5-2); the solvent for desilication reaction is preferably one or more of dichloromethane, chloroform, methanol, ethanol, acetonitrile and tetrahydrofuran.

In the invention, the temperature of the desilication reaction is preferably 20-40 ℃, more preferably 25-35 ℃, and the time of the desilication reaction is preferably 1-4 h, more preferably 2-3 h.

In a specific embodiment of the present invention, it is preferable that the compound having the structure represented by formula II and the desiliconization reagent are added to a solvent and reacted at the desiliconization reaction temperature.

After the desilication reaction is finished, the pH value of the obtained product feed liquid is preferably adjusted to be neutral, then the product feed liquid with the adjusted pH value is extracted by using dichloromethane to obtain a dichloromethane phase, the dichloromethane phase is dried by using anhydrous sodium sulfate, after the drying is finished, a drying agent is removed by filtering, the dried dichloromethane phase is subjected to rotary evaporation, and a solvent in the dichloromethane phase is removed to obtain the compound with the structure shown in the formula III.

After the compound with the structure shown in the formula III is obtained, the compound with the structure shown in the formula III, a catalyst and an oxidant are mixed for catalytic oxidation reaction to obtain the vicinal cyclohexanedione. In the invention, the catalyst for catalytic oxidation reaction is preferably one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium acetate and triethylamine; the oxidant is preferably one or more of phosphorus pentoxide, dimethyl sulfoxide, ferric chloride or manganese dioxide, and is more preferably a mixture of phosphorus pentoxide and dimethyl sulfoxide; in the invention, the phosphorus pentoxide is an electrophilic reagent, and can activate dimethyl sulfoxide, so that the product yield is improved; the solvent for catalytic oxidation reaction is preferably one or more of dichloromethane, N-Dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and tetrahydrofuran.

In the invention, the molar ratio of the compound with the structure shown in the formula III to the oxidant is preferably 1 (1-4), and more preferably 1 (2-3); the dosage of the catalyst is preferably 20-80% of the weight of the compound with the structure shown in the formula III, and more preferably 30-60%.

In the invention, the temperature of the catalytic oxidation reaction is preferably-5 ℃, more preferably-3 ℃, and the time of the catalytic oxidation reaction is preferably 0.5-6 h, more preferably 1-5 h.

In the embodiment of the present invention, preferably, the compound having the structure shown in formula III is dissolved in the solvent, then the catalyst and the oxidant are added into the solution, and the temperature of the mixed solution is reduced to the temperature of the catalytic oxidation reaction for reaction.

After the catalytic oxidation reaction is finished, preferably adopting a hydrochloric acid solution to carry out quenching reaction, and then sequentially filtering, washing, drying and rotationally evaporating a solvent to obtain ortho-cyclohexanedione; the mass fraction of the hydrochloric acid solution is preferably 10%; the washing detergent is preferably a solvent for catalytic oxidation reaction, and the drying agent used for drying is preferably anhydrous sodium sulfate.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention.

Example 1

(1) Adding 9.8g of cyclohexanone, 21mL of triethylamine and 20mL of DMF into a flask, uniformly mixing, heating to 80 ℃, dropwise adding 15mL of trimethylchlorosilane into the solution, keeping the temperature of 80 ℃ for reaction for 2 hours, monitoring the reaction process by TCL, cooling the solution to room temperature after the reaction is finished, performing suction filtration, washing a filter cake by using diethyl ether (20mL multiplied by 3), respectively washing the filtrate by 10mL of 5% HCl, 10mL of 5% sodium bicarbonate solution, 10mL of saturated NaCl solution and 10mL of distilled water for 3 times, and finally performing rotary evaporation to remove the solvent to obtain the compound with the structure shown in the formula I, wherein the yield is 91.2%, and the purity is 95.2%.

(2) Adding 15mL of cyclohexane into a reaction bottle, keeping the temperature of the reaction bottle at-15 ℃, adding 5g of the compound with the structure shown in the formula I into the reaction bottle, adding 2.5g m-CPBA into the reaction bottle in a small amount for multiple times after stirring and dissolving, reacting for 1h after the addition is finished, and then standing at room temperature and stirring for 2 h. And after the reaction is finished, carrying out suction filtration, removing filter residues, and carrying out rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula II, wherein the yield is 86% and the purity is 94.5%.

(3) A flask was charged with 15mL of dichloromethane, 3g of the compound having the structure represented by formula II and 1.5g of potassium fluoride, reacted at 30 ℃ for 2h, and the progress of the reaction was monitored by TCL. After the reaction is finished, the pH is adjusted to be neutral, dichloromethane is used for extracting a solution, the obtained dichloromethane phase is dried and dehydrated by anhydrous sodium sulfate, then a drying agent is removed by filtration, and the solvent is evaporated by rotary evaporation to obtain the compound with the structure shown in the formula III, wherein the yield is 87%, and the purity is 94.1%.

(4) 4mL of DMSO and 0.1g of phosphorus pentoxide were sequentially added to 20mL of a dichloromethane solution containing 2g of the compound having the structure represented by formula III, reacted at-5 ℃ for 1 hour, 2mL of triethylamine was added dropwise to the reaction flask, and the reaction was continued for 1 hour. After the reaction is finished, quenching the reaction by using 10% hydrochloric acid, and then sequentially filtering, washing, drying and rotary evaporating the solvent to obtain the ortho-cyclohexanedione, wherein the yield is 82.5%, and the purity is 95%.

FIG. 1 is a gas chromatograph of a compound having the structure shown in formula I prepared in this example;

FIG. 2 is a gas chromatograph of a compound having the structure shown in formula II prepared in this example;

FIG. 3 is a gas chromatograph of a compound having the structure shown in formula III prepared in this example;

FIG. 4 shows the preparation of orthocyclohexanedione in this example¹H-NMR chart.

As can be seen from FIGS. 1 to 4, the products obtained in the steps 1 to 4 of the present invention conform to the expected structure.

Example 2

(1) Adding 98g of cyclohexanone, 100mL of 30% NaOH solution, 1g of potassium iodide and 200mL of DMF into a flask, uniformly mixing, heating to 70 ℃, dropwise adding 150mL of trimethylchlorosilane into the solution, keeping the 70 ℃ for reaction for 3 hours, monitoring the reaction process by TCL, cooling the solution to room temperature after the reaction is finished, performing suction filtration, washing a filter cake by using diethyl ether (50mL multiplied by 3), respectively washing filtrate by 50mL of 5% HCl, 50mL of 5% sodium bicarbonate solution, 50mL of saturated NaCl solution and 50mL of distilled water for 3 times, and finally, evaporating the solvent by rotary evaporation to obtain the compound with the structure shown in the formula I, wherein the yield is 88.9%, and the purity is 95.7%.

(2) Adding 100mL of cyclohexane into a reaction bottle, keeping the temperature of the reaction bottle at-15 ℃, adding 65g of the compound with the structure shown in the formula I into the reaction bottle, stirring to dissolve, adding 20g m-CPBA into the reaction bottle in a small amount for multiple times, reacting for 2 hours after the addition is finished, and then standing at room temperature and stirring for 3 hours. And after the reaction is finished, carrying out suction filtration, removing filter residues, and carrying out rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula II, wherein the yield is 88.2%, and the purity is 95.8%.

(3) A flask was charged with 150mL of dichloromethane, 30g of the compound having the structure represented by formula II and 10g of sodium fluoride, reacted at 30 ℃ for 3 hours, and the progress of the reaction was monitored by TCL. After the reaction is finished, adjusting the pH value to be neutral, extracting the solution by using dichloromethane, drying and dehydrating a dichloromethane phase by using anhydrous sodium sulfate, filtering to remove a drying agent, and evaporating the solvent by rotary evaporation to obtain the compound with the structure shown in the formula III, wherein the yield is 89%, and the purity is 93.7%.

(4) 20mL of DMSO and 0.5g of phosphorus pentoxide were sequentially added to 150mL of a dichloromethane solution containing 20g of the compound having the structure represented by formula III, reacted at-5 ℃ for 2 hours, 10mL of triethylamine was added dropwise to the reaction flask, and the reaction was continued for 2 hours. After the reaction is finished, the reaction is quenched by 10% hydrochloric acid, and the product is filtered, washed, dried and rotary evaporated to obtain the orthocyclohexanedione, wherein the yield is 87.5% and the purity is 92.5%.

Example 3

(1) Adding 9.8g of cyclohexanone, 21mL of 30% potassium carbonate solution, 0.3g of sodium iodide and 20mL of DMSO into a flask, uniformly mixing, heating to 80 ℃, dropwise adding 15mL of trimethylchlorosilane into the solution, keeping the temperature of 80 ℃ for reaction for 2 hours, monitoring the reaction process by TCL, cooling the solution to room temperature after the reaction is finished, performing suction filtration, washing a filter cake by using anhydrous acetonitrile (20mL multiplied by 3), respectively washing the filtrate by 10mL of 5% HCl, 10mL of 5% sodium bicarbonate solution, 10mL of saturated NaCl solution and 10mL of distilled water for 3 times, and finally, evaporating the solvent by rotary evaporation to obtain the compound with the structure shown in the formula I, wherein the yield is 83.1%, and the purity is 90.3%.

(2) Adding 15mL of cyclopentane into a reaction bottle, keeping the temperature of the reaction bottle at-15 ℃, adding 5g of the compound with the structure shown in the formula I into the reaction bottle, adding 2.5g m-CPBA into the reaction bottle in a small amount for multiple times after stirring and dissolving, reacting for 1h after the addition is finished, and then standing at room temperature and stirring for 2 h. And after the reaction is finished, carrying out suction filtration, removing filter residues, and carrying out rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula II, wherein the yield is 72% and the purity is 89.6%.

(3) 15mL of ethanol, 3g of the compound having the structure represented by formula II and 1.5g of calcium fluoride were added to the flask, and reacted at 30 ℃ for 2 hours, and the progress of the reaction was monitored by TCL. After the reaction is finished, adjusting the pH value to be neutral, extracting the solution by using dichloromethane, drying and dehydrating a dichloromethane phase by using anhydrous sodium sulfate, then filtering to remove a drying agent, and evaporating the solvent by rotary evaporation to obtain the compound with the structure shown in the formula III, wherein the yield is 70%, and the purity is 88.7%.

(4) 3g of manganese dioxide was sequentially added to 20mL of a dichloromethane solution containing 2g of the compound having the structure represented by formula III, reacted at-5 ℃ for 1 hour, and 2mL of ammonium acetate was added dropwise to the reaction flask, and the reaction was continued for 1 hour. After the reaction is finished, quenching the reaction by using 10% hydrochloric acid, filtering, washing, drying and rotary evaporating the solvent to obtain the orthocyclohexanedione, wherein the yield is 51.5%, and the purity is 85%.

Example 4

(1) Adding 50g of cyclohexanone, 100mL of pyridine, 5g of potassium tert-butoxide and 100mL of tetrahydrofuran into a flask, uniformly mixing, heating to 85 ℃, dropwise adding 90mL of trimethylchlorosilane into the solution, keeping the temperature of 85 ℃ for reaction for 4 hours, monitoring the reaction process by TCL, cooling the solution to room temperature after the reaction is finished, performing suction filtration, washing a filter cake by using diethyl ether (40mL multiplied by 3), respectively washing the filtrate by 50mL of 5% HCl, 50mL of 5% sodium bicarbonate solution, 50mL of saturated NaCl solution and 50mL of distilled water for 3 times, and finally, evaporating the solvent by rotation to dryness to obtain the compound with the structure shown in the formula I, wherein the yield is 96.6%, and the purity is 95.7%.

(2) Adding 80mL of petroleum ether into a reaction bottle, keeping the temperature of the reaction bottle at 0 ℃, adding 30g of the compound with the structure shown in the formula I into the reaction bottle, adding 10g m-CPBA into the reaction bottle in a small amount for multiple times after stirring and dissolving, reacting for 2 hours after the addition is finished, and then standing at room temperature and stirring for 3 hours. And after the reaction is finished, carrying out suction filtration, removing filter residues, and carrying out rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula II, wherein the yield is 91.7%, and the purity is 94.9%.

(3) A flask was charged with 75mL of chloroform solution, 10g of the compound having the structure represented by formula II and 8g of hydrofluoric acid, reacted at 40 ℃ for 2 hours, and the progress of the reaction was monitored by TCL. After the reaction is finished, adjusting the pH value to be neutral, extracting the solution by using dichloromethane, drying and dehydrating a dichloromethane phase by using anhydrous sodium sulfate, then filtering to remove a drying agent, and evaporating the solvent by rotary evaporation to obtain the compound with the structure shown in the formula III, wherein the yield is 85%, and the purity is 94.3%.

(4) 8.5g of ferric chloride was sequentially added to 80mL of tetrahydrofuran solution containing 6g of the compound having the structure represented by formula III, reacted at-5 ℃ for 1.5h, 10mL of triethylamine was added dropwise to the reaction flask, and the reaction was continued for 3 h. After the reaction is finished, quenching the reaction by using 10% hydrochloric acid, filtering, washing, drying and rotary evaporating the solvent to obtain the o-cyclohexanedione, wherein the yield is 81.7%, and the purity is 96%.

Example 5

(1) Adding 1000g of cyclohexanone, 2000mL of triethylamine and 2000mL of DMF into a reaction kettle, uniformly mixing, heating to 80 ℃, dropwise adding 1500mL of trimethylchlorosilane into the solution, keeping the temperature of 80 ℃ for reaction for 5 hours, monitoring the reaction process by TCL, cooling the solution to room temperature after the reaction is finished, filtering, washing with diethyl ether (500mL multiplied by 3), and then carrying out rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula I, wherein the yield is 94.8%, and the purity is 97.2%.

(2) 1500mL of cyclohexane was added to the reactor, the temperature of the reactor was maintained at-15 ℃, 500g of the compound having the structure of formula I was added to the flask, and after stirring and dissolution, 250g m-CPBA was added thereto in small amounts, and after the addition, the reaction was carried out for 5 hours, followed by standing and stirring at room temperature for 3 hours. And after the reaction is finished, filtering, removing filter residues, and performing rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula II, wherein the yield is 93%, and the purity is 97.5%.

(3) 1500mL of methylene chloride, 300g of the compound having the structure represented by formula II and 150g of potassium fluoride were charged into a reactor, and reacted at room temperature for 5 hours, and the progress of the reaction was monitored by TCL. After the reaction is finished, the pH value is adjusted to be neutral, dichloromethane is used for extracting a solution, anhydrous sodium sulfate is used for drying and dehydrating a dichloromethane phase, then a drying agent is removed by filtration, and a solvent is evaporated by rotary evaporation to obtain a compound with a structure shown in a formula III, wherein the yield is 95.3%, and the purity is 96.1%.

(4) 100mL of DMSO and 2g of phosphorus pentoxide were sequentially added to 2000mL of a dichloromethane solution containing 200g of the compound having the structure represented by formula III, reacted at-5 ℃ for 5 hours, 200mL of triethylamine was added to the reaction flask, and the reaction was continued for 3 hours. After the reaction is finished, quenching the reaction by using 10% hydrochloric acid, filtering, washing, drying and rotary evaporating the solvent to obtain the o-cyclohexanedione, wherein the yield is 83.5%, and the purity is 97%.

Comparative example 1

(1) Adding 9.8g of cyclohexanone, 21mL of sodium hydroxide solution and 20mL of DMF into a flask, uniformly mixing, heating to 80 ℃, dropwise adding 15mL of trimethylchlorosilane into the solution, keeping the temperature of 80 ℃ for reaction for 2 hours, monitoring the reaction process by TCL, cooling the solution to room temperature after the reaction is finished, performing suction filtration, washing a filter cake by using diethyl ether (20mL multiplied by 3), respectively washing the filtrate by 10mL of 5% HCl, 10mL of 5% sodium bicarbonate solution, 10mL of saturated NaCl and 10mL of distilled water for 3 times, and finally, evaporating the solvent by rotation to dryness to obtain the compound with the structure shown in the formula I, wherein the yield is 64.3%, and the purity is 85.2%.

Steps (2), (3) and (4) were the same as in example 1.

Comparative example 2

(1) Same as in step (1) of example 1.

(2) Adding 15mL of cyclohexane into a reaction bottle, placing the reaction bottle at room temperature, adding 5g of the compound with the structure shown in the formula I into the reaction bottle, stirring to dissolve, adding 2.5g m-CPBA into the reaction bottle in a small amount for multiple times, and reacting for 3 hours after the addition is finished. And after the reaction is finished, carrying out suction filtration, removing filter residues, and carrying out rotary evaporation on the filtrate to obtain the compound with the structure shown in the formula II, wherein the yield is 34% and the purity is 67%.

Steps (3) and (4) were the same as in example 1.

Comparative example 3

(1) Same as in step (1) of example 1.

(2) Same as in step (2) of example 1.

(3) A flask was charged with 15mL of dichloromethane, 3g of the compound having the structure represented by formula II and 1.5g of potassium chloride, reacted at 30 ℃ for 2h, and the progress of the reaction was monitored by TCL. After the reaction is finished, the pH value is adjusted to be neutral, dichloromethane is used for extracting solution, anhydrous sodium sulfate is used for drying and dehydrating a dichloromethane phase, then a drying agent is removed by filtration, and the solvent is evaporated by rotary evaporation. No corresponding product was obtained.

(4) Same as in step (4) of example 1.

Comparative example 4

Steps (1), (2) and (3) were the same as in example 1.

(4) 4mL of DMSO was added to a 20mL dichloromethane solution containing 2g of the compound having the structure represented by formula III, and the reaction was carried out at-5 ℃ for 1h, and 2mL of triethylamine was added dropwise to the reaction flask and the reaction was continued for 1 h. After the reaction is finished, quenching the reaction by using 10% hydrochloric acid, filtering, washing, drying and rotary evaporating the solvent to obtain the o-cyclohexanedione, wherein the yield is 42.5%, and the purity is 75%.

As can be seen from the comparative examples, the catalyst in the step (1) of the invention can promote the reaction, accelerate the reaction rate and improve the yield and purity of the product; the step (2) of the invention needs to be carried out at low temperature, if the reaction is placed at room temperature, the reaction is incomplete, the yield and purity of the product are reduced, and the reaction is not facilitated; in the invention, a desiliconization reagent is required in the step (3), and potassium chloride can not cause desiliconization reaction; when DMSO is used as an oxidant in the step (4), electrophiles such as phosphorus pentoxide and the like need to be added to activate the DMSO, otherwise, the yield and purity of the product are low.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.