A method for preparing carboxylic acid ester compounds by oxidative cleavage of carbon-carbon double bonds of olefin compounds

Abstract

The application discloses a method for preparing carboxylic acid ester compounds by oxidizing and breaking carbon-carbon double bonds of olefin compounds. The method comprises the following steps: adding olefin compounds, an additive and a nitrogen-doped mesoporous carbon loaded cobalt-based catalyst into a primary aliphatic alcohol solvent, placing the mixture into a pressure container, and introducing an oxygen source gas with a pressure of 0.5-0.9 MPa at a reaction temperature of 80-150 DEG C. The product after the reaction is a carboxylic acid ester compound. The method has a wide application range, the reaction conditions are easy to control, the catalyst can be recycled, the post-treatment is simple, and the method is suitable for industrial production.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis, specifically relating to a method for directly preparing organic carboxylic acid esters from olefin compounds by oxidative cleavage of carbon-carbon double bonds. Background Technology

[0002] Organic carboxylic acid esters are widely used as basic materials in organic synthesis in the production of fine chemicals, agrochemicals, and pharmaceuticals. Traditional methods for synthesizing organic carboxylic acid esters generally require carboxylic acids, acid anhydrides, acyl halides, or ketones, and involve multiple reaction steps, often resulting in waste of raw materials and the generation of byproducts. Subsequent efforts have focused on the direct oxidative esterification of aldehydes to synthesize esters in one step. However, these methods often use stoichiometric or excess oxidants, such as manganese dioxide, potassium persulfate, and peroxides. While these methods are useful, they generate a large number of toxic and useless byproducts, and the aldehydes used as substrates are usually derived from the oxidation of alcohols. Another method for preparing carboxylic acid esters involves the direct oxidative esterification of primary alcohols to synthesize esters in one step. However, this method primarily uses noble metals Au and Pd as catalysts, with some catalytic systems employing cobalt-based catalysts supported on carbon materials.

[0003] Alkenes are an important class of organic compounds that can be converted into a variety of organic chemicals. Currently, routes for obtaining organic carboxylic acid esters from alkenes via oxidative cleavage of carbon-carbon double bonds are rarely reported. This method not only provides a pathway for preparing organic carboxylic acid esters but also offers a way to convert and utilize alkenes. Summary of the Invention

[0004] This invention provides a novel route for obtaining organic carboxylic acid esters from olefin compounds via oxidative cleavage of carbon-carbon double bonds. This route enables the efficient and low-cost preparation of carboxylic acid esters and has a wide range of applicable substrates.

[0005] The technical solution adopted in this invention is:

[0006] 1. Method for preparing carboxylic acid esters by oxidative cleavage of carbon-carbon double bonds in olefins: An olefin compound and a single-atom catalyst (including those with a specific surface area of ​​1000-1200 m²) are used. 2 One or more single-atom catalysts with a pore size of 3.2-4.5 nm (g), additives, and aliphatic primary alcohol solvents are sequentially added to a 25 mL stainless steel high-pressure reactor. The reactor is then purged with 0.5 MPa oxygen source gas, and the reaction is repeated three times. The reactor is then placed in an oil bath at 130-150℃ and reacted for 8-24 hours. This process oxidizes and breaks down the carbon-carbon double bond into the corresponding carboxylic acid ester compounds (C=C breaks down to remove one carbon atom, and the remaining carbon atom becomes the ester corresponding to the primary alcohol).

[0007] 2. In the above technical solution, the olefin compound is one or more of the following: aromatic olefins: R1 = one or more of the following: H, 4-F, 3-F, 2-F, 4-Cl, 3-Cl, 2-Cl, 4-Br, 3-Br, 4-CF3, 4-MeO, 3-MeO, 2-MeO, 4-Me, 4-tBu, 4-Ph

[0008] n = 1, 2, 3 or more of the following:

[0009] R2 = one or more of Me, Et, Ph, and cyclohexene;

[0010] Heterocyclic alkenes: one or more of 4-vinylpyridine, 2-vinylpyridine, 2-vinylthiophene, and 2-vinylfuran;

[0011] Fatty acids and olefins: n = 1-6 or more of the following:

[0012] 3. In the above technical solution, the method for preparing the iron single-atom catalyst is as follows: 14.0-18.0 g of Fe(NO3)2·6H2O (preferably 15.8-17.2 g) and 14.0-18.0 g of Zn(NO3)2·6H2O (preferably 15.5-17.8 g) are dissolved in 200-300 mL (preferably 260-300 mL) of methanol. Then, the above solution is poured into 200-300 mL (preferably 260-300 mL) of methanol containing 16.5-19.8 g of 2-methylimidazole (preferably 17.3-19.0 g). The resulting solution is magnetically stirred at room temperature for 6-24 h (preferably 12-24 h). The precipitate was separated and washed 3-7 times (preferably 4-6 times) with 30-60 mL (preferably 50-55 mL) of methanol, and finally dried under vacuum at 60-70℃ (preferably 60-65℃) overnight. The obtained powder was heated to 800-1000℃ under N2 atmosphere at a heating rate of 3-10℃ / min (preferably 5-10℃ / min) and held for 6-12 h (preferably 10-12 h). After natural cooling to room temperature, the target product was obtained and named Fe-NC.

[0013] Alternatively, the cobalt single-atom catalyst can be prepared as follows: 14.0-18.0 g of Co(NO3)2·6H2O (preferably 15.8-17.2 g) and 14.0-18.0 g of Zn(NO3)2·6H2O (preferably 15.5-17.8 g) are dissolved in 200-300 mL (preferably 260-300 mL) of methanol. Then, the above solution is poured into 200-300 mL (preferably 260-300 mL) of methanol containing 16.5-19.8 g of 2-methylimidazole (preferably 17.3-19.0 g). The resulting solution is magnetically stirred at room temperature for 6-24 h (preferably 12-24 h). The resulting precipitate is separated and washed 3-7 times (preferably 4-6 times) with 30-60 mL (preferably 50-55 mL) of methanol, and finally vacuum dried overnight at 60-70 °C (preferably 60-65 °C). The obtained powder was heated to 800-1000°C under a N2 atmosphere at a heating rate of 3-10°C / min (preferably 5-10°C / min) and held for 6-12 h (preferably 10-12 h). After natural cooling to room temperature, the target product was obtained and named Co-NC.

[0014] Alternatively, the copper single-atom catalyst can be prepared as follows: 14.0-18.0 g of Cu(NO3)2·3H2O (preferably 15.8-17.2 g) and 14.0-18.0 g of Zn(NO3)2·6H2O (preferably 15.5-17.8 g) are dissolved in 200-300 mL (preferably 260-300 mL) of methanol. Then, the above solution is poured into 200-300 mL (preferably 260-300 mL) of methanol containing 16.5-19.8 g of 2-methylimidazole (preferably 17.3-19.0 g). The resulting solution is magnetically stirred at room temperature for 6-24 h (preferably 12-24 h). The resulting precipitate is separated and washed 3-7 times (preferably 4-6 times) with 30-60 mL (preferably 50-55 mL) of methanol, and finally vacuum dried overnight at 60-70 °C (preferably 60-65 °C). The obtained powder was heated to 800-1000℃ under N2 atmosphere at a heating rate of 3-10℃ / min (preferably 5-10℃ / min) and held for 6-12h (preferably 10-12h). After natural cooling to room temperature, the target product was obtained and named Cu-NC.

[0015] 4. In the above technical solution, the additive is characterized in that it is an alkaline inorganic compound, including one or more of potassium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, and potassium phosphate.

[0016] 5. In the above technical solution, the primary fatty alcohol solvent is one or more of C1-C10, and the amount used is 2-3 mL for every 0.5 mmol of olefin compound, preferably 2-2.5 mL.

[0017] 6. In the above technical solution, the gas pressure is 0.5-0.9 MPa, preferably 0.5-0.7 MPa; the reaction temperature is 80-150℃, preferably 130-145℃; and the reaction time is 6-30 h, preferably 8-12 h.

[0018] 7. In the above technical solution, the oxygen source is characterized by being pure oxygen or one or two types of air.

[0019] 8. In the above technical solution, the molar ratio of the amount of additive added to the amount of olefin reactant fed is 0.10-0.15, preferably 0.12-0.15.

[0020] 9. In the above technical solution, the molar ratio of the amount of catalyst added to the amount of olefin reactant fed is 0.03-0.05, preferably 0.02-0.05.

[0021] Compared with existing methods for preparing organic carboxylic acid esters, this invention has the following advantages:

[0022] The catalyst is a heterogeneous catalyst, which is easy to recover and reuse.

[0023] It has a wide substrate range and is applicable to a variety of olefin compounds.

[0024] The product, carboxylic esters, exhibits high selectivity with fewer byproducts.

[0025] The nitrogen-doped mesoporous carbon-supported single-atom catalyst used in this invention has high catalyst activity and the separation yield of carboxylic acid ester compounds after the reaction is up to 99%. This method has a wide range of applications, the reaction conditions are easy to control, the catalyst can be recycled, and the post-processing is simple, making it suitable for industrial production. Attached Figure Description

[0026] Figure 1 This is a scanning electron microscope (TEM) image of an iron single-atom catalyst. Detailed Implementation

[0027] To provide a more detailed description of the present invention, several specific implementation examples are given below, but the present invention is not limited to these embodiments.

[0028] The following example illustrates the preparation method of an iron single-atom catalyst: 16.38 g of Fe(NO3)2·6H2O and 16.74 g of Zn(NO3)2·6H2O were dissolved in 300 mL of methanol. Subsequently, the solution was poured into 300 mL of methanol containing 18.36 g of 2-methylimidazole. The resulting solution was magnetically stirred at room temperature for 12 h. The precipitate was separated and washed five times with 50 mL of methanol, and finally dried under vacuum at 65 °C overnight. The resulting powder was heated from room temperature to 1000 °C at a heating rate of 5 °C / min under a N2 atmosphere and held for 12 h. After natural cooling to room temperature, the target product, named Fe-NC-1000, was obtained, with a specific surface area of ​​1157 m² / g and a pore size of 0.75-1.9 nm. TEM observation of Fe-NC-1000 showed... Figure 1 As shown, the results indicate that no aggregated metallic iron or iron oxides were found throughout the detection area. These results suggest that iron species are highly dispersed in the material at the single-atom level.

[0029] The cobalt single-atom catalyst preparation method used in the following example is as follows: 16.38 g Co(NO3)2·6H2O and 16.74 g Zn(NO3)2·6H2O were dissolved in 300 mL methanol. Then, the above solution was poured into 300 mL methanol containing 18.36 g 2-methylimidazole. The resulting solution was magnetically stirred at room temperature for 12 h. The resulting precipitate was separated and washed five times with 50 mL methanol, and finally dried under vacuum at 65 °C overnight. The obtained powder was heated from room temperature to 1000 °C at a heating rate of 5 °C / min under a N2 atmosphere and held for 12 h. After natural cooling to room temperature, the target product, named Co-NC-1000, was obtained with a specific surface area of ​​1103 m². 2 / g, with a pore size of 0.73-1.7nm. TEM observation of Co-NC-1000 showed no aggregated metallic cobalt or cobalt oxides detected throughout the detection area. These results indicate that cobalt species are highly dispersed in the material at the single-atom level.

[0030] The copper single-atom catalyst preparation method used in the following example is as follows: 16.38 g Cu(NO3)2·3H2O and 16.74 g Zn(NO3)2·6H2O were dissolved in 300 mL methanol. Then, the above solution was poured into 300 mL methanol containing 18.36 g 2-methylimidazole. The resulting solution was magnetically stirred at room temperature for 12 h. The resulting precipitate was separated and washed five times with 50 mL methanol, and finally dried under vacuum at 65 °C overnight. The obtained powder was heated from room temperature to 1000 °C at a heating rate of 5 °C / min under a N2 atmosphere and held for 12 h. After natural cooling to room temperature, the target product, named Cu-NC-1000, was obtained with a specific surface area of ​​1088 m². 2 / g, with a pore size of 0.72-1.65 nm. TEM observation showed that Cu-NC-1000 is also a single-atom catalyst, and the results indicated that no aggregated metallic copper or copper oxides were found throughout the detection area. These results suggest that copper species are highly dispersed in the material at the single-atom level.

[0031] The non-metallic catalyst preparation method used in the following example is as follows: 16.74 g of Zn(NO3)2·6H2O was dissolved in 300 mL of methanol. Then, the above solution was poured into 300 mL of methanol containing 18.36 g of 2-methylimidazole. The resulting solution was magnetically stirred at room temperature for 12 h. The precipitate was separated and washed five times with 50 mL of methanol, and finally dried under vacuum at 65 °C overnight. The obtained powder was heated from room temperature to 1000 °C at a heating rate of 5 °C / min under N2 atmosphere and held for 12 h. After natural cooling to room temperature, the target product was obtained and named NC-1000; the target product, named NC-1000, has a specific surface area of ​​1206 m². 2 / g, with a pore size of 3.45nm.

[0032] Example 1

[0033] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. The atmosphere inside the reactor was replaced with oxygen three times (0.5 MPa oxygen source gas was introduced and then emptied, and the process of introducing oxygen source gas and emptying the reactor was repeated three times, the same below). Then, 0.5 MPa oxygen was introduced, and the reactor was placed in an oil bath at 130 °C for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the clear liquid was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of methyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0034] Example 2

[0035] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), Na2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of methyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0036] Example 3

[0037] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), Cs2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0038] Example 4

[0039] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K3PO4 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0040] Example 5

[0041] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), KOH (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0042] Example 6

[0043] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), NaOH (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0044] Example 7

[0045] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0046] Example 8

[0047] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (5 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0048] Example 9

[0049] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (20 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of methyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0050] Example 10

[0051] Fe-NC-1000 (5 mol% relative to 4-fluorostyrene raw material), 4-fluorostyrene (0.5 mmol), K2CO3 (15 mol% relative to 4-fluorostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor with oxygen three times, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and 20 mg of internal standard naphthalene and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-fluorobenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0052] Example 11

[0053] Fe-NC-1000 (5 mol% relative to 3-fluorostyrene raw material), 3-fluorostyrene (0.5 mmol), K2CO3 (15 mol% relative to 3-fluorostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 3-fluorobenzoate by gas chromatography quantitative analysis is shown in Table 1.

[0054] Example 12

[0055] Fe-NC-1000 (5 mol% relative to 2-fluorostyrene raw material), 2-fluorostyrene (0.5 mmol), K2CO3 (15 mol% relative to 2-fluorostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 2-fluorobenzoate was quantitatively analyzed by gas chromatography and is shown in Table 1.

[0056] Example 13

[0057] Fe-NC-1000 (5 mol% relative to 4-chlorostyrene raw material), 4-chlorostyrene (0.5 mmol), K2CO3 (15 mol% relative to 4-chlorostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-chlorobenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0058] Example 14

[0059] Fe-NC-1000 (5 mol% relative to 3-chlorostyrene raw material), 3-chlorostyrene (0.5 mmol), K2CO3 (15 mol% relative to 3-chlorostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 3-chlorobenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0060] Example 15

[0061] Fe-NC-1000 (5 mol% relative to 2-chlorostyrene raw material), 2-chlorostyrene (0.5 mmol), K2CO3 (15 mol% relative to 2-chlorostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 2-chlorobenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0062] Example 16

[0063] Fe-NC-1000 (3 mol% relative to 4-bromostyrene raw material), 4-bromostyrene (0.5 mmol), K2CO3 (15 mol% relative to 4-bromostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-bromobenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0064] Example 17

[0065] Fe-NC-1000 (3 mol% relative to 3-bromostyrene raw material), 3-bromostyrene (0.5 mmol), K2CO3 (15 mol% relative to 3-bromostyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 3-bromobenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0066] Example 18

[0067] Fe-NC-1000 (5 mol% relative to 4-(trifluoromethyl)styrene), 4-(trifluoromethyl)styrene (0.5 mmol), K2CO3 (15 mol% relative to 4-(trifluoromethyl)styrene), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-(trifluoromethyl)benzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0068] Example 19

[0069] Fe-NC-1000 (5 mol% relative to 4-methylstyrene raw material), 4-methylstyrene (0.5 mmol), K2CO3 (15 mol% relative to 4-methylstyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-methylbenzoate by gas chromatography quantitative analysis is shown in Table 1.

[0070] Example 20

[0071] Fe-NC-1000 (5 mol% relative to 3-methylstyrene raw material), 4-methylstyrene (0.5 mmol), K2CO3 (15 mol% relative to 3-methylstyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor with oxygen three times, 0.5 MPa of oxygen was introduced, and the reactor was placed in an oil bath at 130 °C for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 3-methylbenzoate was quantitatively analyzed by gas chromatography and is shown in Table 1.

[0072] Example 21

[0073] Fe-NC-1000 (5 mol% relative to 2-methylstyrene raw material), 2-methylstyrene (0.5 mmol), K2CO3 (15 mol% relative to 2-methylstyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 2-methylbenzoate was quantitatively analyzed by gas chromatography and is shown in Table 1.

[0074] Example 22

[0075] Fe-NC-1000 (5 mol% relative to 4-methoxystyrene raw material), 4-methoxystyrene (0.5 mmol), K2CO3 (15 mol% relative to 4-methoxystyrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor with oxygen three times, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-methoxybenzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0076] Example 23

[0077] Fe-NC-1000 (5 mol% relative to 4-tert-butylstyrene feedstock), 4-tert-butylstyrene (0.5 mmol), K2CO3 (15 mol% relative to 4-tert-butylstyrene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-tert-butylbenzoate was quantitatively determined by gas chromatography and is shown in Table 1.

[0078] Example 24

[0079] Fe-NC-1000 (5 mol% relative to 4-vinylbiphenyl feedstock), 4-vinylbiphenyl (0.5 mmol), K2CO3 (15 mol% relative to 4-vinylbiphenyl feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product biphenyl-4-carboxylic acid methyl ester by GC-MS is shown in Table 1.

[0080] Example 25

[0081] Fe-NC-1000 (5 mol% relative to allylbenzene raw material), allylbenzene (0.5 mmol), K2CO3 (15 mol% relative to allylbenzene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of methyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0082] Example 26

[0083] Fe-NC-1000 (5 mol% relative to 4-phenyl-1-butene feedstock), 4-phenyl-1-butene (0.5 mmol), K2CO3 (15 mol% relative to 4-phenyl-1-butene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by GC, is shown in Table 1.

[0084] Example 27

[0085] Fe-NC-1000 (5 mol% relative to 5-phenyl-1-pentene feedstock), 5-phenyl-1-pentene (0.5 mmol), K2CO3 (15 mol% relative to 5-phenyl-1-pentene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by GC, is shown in Table 1.

[0086] Example 28

[0087] Fe-NC-1000 (5 mol% relative to 1-propenylbenzene feedstock), 1-propenylbenzene (0.5 mmol), K2CO3 (15 mol% relative to 1-propenylbenzene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by GC, is shown in Table 1.

[0088] Example 29

[0089] Fe-NC-1000 (5 mol% relative to 2-methyl-1-phenylpropene feedstock), 2-methyl-1-phenylpropene (0.5 mmol), K2CO3 (15 mol% relative to 2-methyl-1-phenylpropene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by GC, is shown in Table 1.

[0090] Example 30

[0091] Fe-NC-1000 (5 mol% relative to trans-stilbene raw material), trans-stilbene (0.5 mmol), K2CO3 (15 mol% relative to trans-stilbene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate by gas chromatography quantitative analysis is shown in Table 1.

[0092] Example 31

[0093] Fe-NC-1000 (5 mol% relative to 1-phenyl-1-cyclohexene raw material), 1-phenyl-1-cyclohexene (0.5 mmol), K2CO3 (15 mol% relative to 1-phenyl-1-cyclohexene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate by gas chromatography quantitative analysis is shown in Table 1.

[0094] Example 32

[0095] Fe-NC-1000 (5 mol% relative to 4-vinylpyridine raw material), 4-vinylpyridine (0.5 mmol), K2CO3 (15 mol% relative to 4-vinylpyridine raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 4-pyridinecarboxylate was quantitatively analyzed by gas chromatography and is shown in Table 1.

[0096] Example 33

[0097] Fe-NC-1000 (5 mol% relative to 2-vinylpyridine raw material), 2-vinylpyridine (0.5 mmol), K2CO3 (15 mol% relative to 2-vinylpyridine raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 2-pyridinecarboxylate by gas chromatography quantitative analysis is shown in Table 1.

[0098] Example 34

[0099] Fe-NC-1000 (5 mol% relative to 2-vinylthiophene raw material), 2-vinylthiophene (0.5 mmol), K2CO3 (15 mol% relative to 2-vinylthiophene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl 2-pyridinecarboxylate by gas chromatography quantitative analysis is shown in Table 1.

[0100] Example 35

[0101] Fe-NC-1000 (5 mol% relative to 2-vinylfuran feedstock), 2-vinylfuran (0.5 mmol), K2CO3 (15 mol% relative to 2-vinylfuran feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product methyl 2-pyridinecarboxylate, which was quantitatively determined by GC, is shown in Table 1.

[0102] Example 36

[0103] Fe-NC-1000 (5 mol% relative to 1-hexene feedstock), 1-hexene (0.5 mmol), K2CO3 (15 mol% relative to 1-hexene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry (GC-MS) to detect the product qualitatively. The yield of the product methyl valerate by GC-MS is shown in Table 1.

[0104] Example 37

[0105] Fe-NC-1000 (relative to 5 mol% of 1-octene feedstock), 1-octene (0.5 mmol), K2CO3 (relative to 15 mol% of 1-octene feedstock), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the clear liquid was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl heptanoate was quantitatively analyzed by gas chromatography and is shown in Table 1.

[0106] Example 38

[0107] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of ethanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product ethyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0108] Example 39

[0109] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of butanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor with oxygen three times, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of butyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0110] Example 40

[0111] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of octanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product octyl benzoate by gas chromatography quantitative analysis is shown in Table 1.

[0112] Example 41

[0113] NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of methyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0114] Example 42

[0115] Co-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0116] Example 43

[0117] Cu-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 130 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, and internal standard naphthalene (20 mg) and 1 mL of methanol were added. After stirring evenly, the mixture was centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0118] Example 44

[0119] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.5 MPa of oxygen was introduced, and the reactor was placed in a 70 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0120] Example 45

[0121] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, 0.3 MPa of oxygen was introduced, and the reactor was placed in a 70 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0122] Example 46

[0123] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere three times with oxygen, air was introduced at 0.5 MPa, and the reactor was placed in a 70 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the supernatant was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of methyl benzoate, the product of gas chromatography quantitative analysis, is shown in Table 1.

[0124] Example 47

[0125] Fe-NC-1000 (5 mol% relative to styrene raw material), styrene (0.5 mmol), K2CO3 (15 mol% relative to styrene raw material), and 2 mL of methanol were sequentially added to a 25 mL stainless steel high-pressure reactor. After purging the reactor atmosphere with nitrogen three times, 0.5 MPa nitrogen was introduced, and the reactor was placed in a 70 °C oil bath for 8 h. After the reaction was completed, the reactor was cooled to room temperature, the reactor was opened, internal standard naphthalene (20 mg) and 1 mL of methanol were added, the mixture was stirred evenly and centrifuged, and an appropriate amount of the clear liquid was taken for gas chromatography-mass spectrometry to detect the product qualitatively. The yield of the product methyl benzoate, which was quantitatively determined by gas chromatography, is shown in Table 1.

[0126] Table 1. Preparation of carboxylic acid esters from olefin compounds by oxidative cleavage of carbon-carbon double bonds.

[0127]

[0128]

[0129]

[0130]

[0131]

[0132] In the table, "-" means that it was not added or was not detected.

[0133] The values ​​in the table show that the type and amount of additives, as well as catalyst conditions, are all crucial for the oxidative cleavage of carbon-carbon double bonds in olefins to prepare carboxylic acid esters. Under optimal conditions, various mono- and di-substituted aromatic olefins, as well as aliphatic olefins, can be efficiently converted into their corresponding carboxylic acid esters, demonstrating the versatility of this method.

Claims

1. A method for preparing carboxylic acid ester compounds by oxidative cleavage of carbon-carbon double bonds in olefin compounds, characterized in that: An olefin compound, catalyst, additive, and methanol solvent are added to a high-pressure reactor. The atmosphere inside the reactor is replaced with oxygen source gas 2-4 times, and finally, 0.5-0.9 MPa of oxygen source gas is introduced. The reactor is placed at 80-150 °C for 8-12 h to oxidize and break the carbon-carbon double bond into the corresponding carboxylic acid ester compound. The olefin compound is 1-hexene or 1-octene, and the corresponding carboxylic acid ester compound is methyl valerate or methyl heptanoate. The catalyst is an iron-based single-atom catalyst. The catalyst is prepared by dissolving 14.0-18.0 g of ferrous nitrate hexahydrate and 14.0-18.0 g of zinc nitrate hexahydrate in 200-300 mL of methanol. Then, the solution is poured into 200-300 mL of methanol containing 16.5-19.8 g of 2-methylimidazole and stirred for 6-24 h. The resulting precipitate is separated, washed 3-7 times with 30-60 mL of methanol, and then heated to 60-70 °C. Vacuum drying at ℃; heating the obtained powder to 800-1000 ℃ at a heating rate of 3-10 ℃ / min under a nitrogen atmosphere, holding for 6-12 h, and naturally cooling to room temperature to obtain the target product named Fe-NC, with a pore size distribution of 0.75-2.0 nm; the additive is one or more of sodium hydroxide, potassium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, and potassium phosphate.

2. The method according to claim 1, characterized in that, For every 0.5 mmol of olefin compound, the amount of methanol used is 2-3 mL.

3. The method according to claim 1, characterized in that, The oxygen source is pure oxygen or one or two types of air, and the total amount of solid and liquid materials in the high-pressure reactor is less than 50% of the reactor's volume.

4. The method according to claim 1, characterized in that, The molar ratio of the amount of additive to the amount of olefin compound fed is 0.10-0.

15.

5. The method according to claim 1, characterized in that, The molar ratio of the catalyst added to the olefin compound feed is 0.03-0.

05.

6. The method according to claim 1, characterized in that, The catalyst has a specific surface area of ​​1000-1250 m² / g.

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