Method for synthesizing furan acetate compound through carbonylation of furfuryl alcohol and derivative

Abstract

The invention discloses a method for synthesizing a furan acetate compound through carbonylation of furfuryl alcohol and derivatives thereof, which comprises the following steps: by taking bio-based furfuryl alcohol and derivatives as raw materials, carbon monoxide gas as a carbonyl source and a polymer containing an aryl phosphine ligand and palladium salt as a catalyst, carrying out carbonylation reaction in an organic solvent to obtain a product, namely the furan acetate compound. The heterogeneous polymer is used as the carbonylation catalyst, additives such as alkali and dimethyl carbonate do not need to be used, and the catalyst is high in activity, easy to separate and recycle and suitable for industrial production.

Description

Technical Field

[0001] The present invention relates to a method for carbonylating furfuryl alcohol and its derivatives to synthesize furan acetic acid esters, and particularly to a method for carbonylating furfuryl alcohol and its derivatives to synthesize furan acetic acid esters by using a polymer containing an arylphosphine ligand and a palladium salt, belonging to the fields of chemical synthesis and value-added conversion of biomass resources. Background Art

[0002] Furan acetic acid esters are a kind of biomass-derived fine chemicals and intermediates with wide applications, and their structural formula is as follows: Among them, the substituents R1 and R2 are selected from hydrogen, alkoxy, alkyl, carboxyl, aldehyde, and hydroxyl.

[0003] Furan acetic acid esters can be used as organic synthesis intermediates and are widely used in fields such as plastics, coatings, pharmaceuticals, fragrances, and foods. Currently, the main preparation method of furan acetic acid esters is to react furan or furfuryl alcohol with cyanide and then hydrolyze to obtain the acid, and then further esterify. This route uses highly toxic cyanide and causes serious environmental pollution. Chinese Patent CN112898247B discloses a route for synthesizing furan acetic acid ester compounds using bio-based furfuryl alcohol and carbon monoxide as raw materials and a combination of palladium metal salt, phosphine ligand, dimethyl carbonate, and base as catalysts. This route requires adding dimethyl carbonate and base as auxiliaries to the reaction system, which not only brings inconvenience to the separation of products and solvents, but also dimethyl carbonate decomposes and consumes during the reaction process, and a large amount needs to be replenished during the catalyst recycling process, significantly increasing the production cost of the product. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for carbonylating furfuryl alcohol and its derivatives to synthesize furan acetic acid esters by using a polymer containing an arylphosphine ligand and a palladium salt. The present invention uses furfuryl alcohol and its derivatives as raw materials and a polymer containing an arylphosphine ligand and a palladium salt as a catalyst to carry out a carbonylation reaction to increase the carbon chain of the raw materials and synthesize furan acetic acid ester compounds. The synthesis route of the present invention does not require the use of additives such as bases and dimethyl carbonate, and the catalyst is easy to separate, providing an important technical solution and experimental basis for the high-value utilization of bio-based furfuryl alcohol and its derivatives.

[0005] A method for carbonylating furfuryl alcohol and its derivatives to synthesize furan acetic acid esters by using a polymer containing an arylphosphine ligand and a palladium salt is to add the raw material furfuryl alcohol or its derivative and a polymer catalyst containing an arylphosphine ligand and a palladium salt to an organic solvent, introduce carbon monoxide gas, and carry out a carbonylation reaction at a temperature of 30 - 200 °C and a pressure of 0.1 - 6 MPa for 0.5 - 20 hours. The reaction product is the furan acetic acid ester compound; The structural formula of the raw material furfuryl alcohol and its derivatives is: Wherein, the substituents R1 and R2 are selected from hydrogen, alkoxy, alkyl, carboxyl, aldehyde or hydroxyl.

[0006] The preparation of the polymer catalyst containing an aryl phosphine ligand and a palladium salt includes two preparation processes; The first preparation process comprises the following steps: (1) Under vacuum conditions, using an aryl phosphine ligand and 2,3,5,6-tetrafluorophenylenedimethanol as raw materials, trifluoromethanesulfonic acid as a catalyst and a solvent, a polymerization reaction is carried out at 50-160° C. for 4-48 hours. After the reaction is completed, the reaction system is cooled and quenched with water. The insoluble solid is filtered, washed, and dried to obtain a phosphorus-containing polymer carrier; the molar ratio of the aryl phosphine ligand to 2,3,5,6-tetrafluorophenylenedimethanol is 1:1.5-1:8; (2) stirring the obtained phosphorus-containing polymer support and palladium salt in methanol at 50-120° C. for 6-24 hours, filtering, washing and drying to obtain a polymer catalyst containing an aromatic phosphine ligand and a palladium salt; the mass ratio of the phosphorus-containing polymer support to the palladium salt is 99.9:0.1-95:5; The second preparation process comprises the following steps: (1) Under a nitrogen atmosphere, a palladium salt and an aryl phosphine ligand are heated in a methanol solvent, and stirred and refluxed at 50-120° C. for 2-24 hours. After the reaction is completed, the reaction solution is allowed to stand, and a palladium-phosphine complex is obtained by suction filtration, washing, and drying. The molar ratio of the palladium salt to the aryl phosphine ligand is 1:1-1:8. (2) Under vacuum conditions, a palladium-phosphine complex and 2,3,5,6-tetrafluorophenylenedimethanol are used as raw materials, trifluoromethanesulfonic acid is used as a catalyst and a solvent, and a polymerization reaction is carried out at 50-160°C for 4-48 hours. After the reaction is completed, the reaction system is cooled and quenched with water. The insoluble solid is filtered, washed, and dried to obtain a polymer catalyst containing an aromatic phosphine ligand and a palladium salt. The molar ratio of the palladium-phosphine complex to 2,3,5,6-tetrafluorophenylenedimethanol is 1:1.5-1:8.

[0007] The palladium salt is selected from at least one of palladium acetate, palladium nitrate, palladium chloride, palladium bromide, palladium carbon, and palladium acetylacetonate.

[0008] The aromatic phosphine ligand is selected from at least one of triphenylphosphine, 1,1'-bis(diphenylphosphino)ferrocene, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,5-bis(diphenylphosphino)pentane, 1,6-bis(diphenylphosphino)hexane, tri-tert-butylphosphine, tricyclohexylphosphine, 1,2-bis(diphenylphosphino)benzene, 1,1'-binaphthyl-2,2'-bisdiphenylphosphine, bis(2-diphenylphosphinophenyl)ether, tri-p-phenylmethylphosphine, tri(4-fluorophenyl)phosphine, tri(pentafluorophenyl)phosphine, tri(4-chlorophenyl)phosphine, and tri(2-furan)phosphine.

[0009] The mass ratio of furfuryl alcohol and its derivatives to the polymer catalyst containing arylphosphine ligand and palladium salt is 1:0.05 - 1:1.

[0010] The organic solvent is at least one of tetrahydrofuran, dichloroethane, methanol, ethanol, propanol, butanol, toluene, and cyclohexane.

[0011] The present invention has the following advantages over the prior art: 1. The preparation route does not require the use of additives such as alkali and dimethyl carbonate, reducing production costs.

[0012] 2. The present invention uses a heterogeneous polymer as the catalyst, which can be recycled by simple filtration separation. It has excellent stability and still has a high yield after being recycled multiple times (the yield of furan acetate remains above 90% after being recycled 6 times), significantly reducing the separation cost of the product and the catalyst.

[0013] 3. The reaction system of the present invention is simple, the conditions are mild, and the yield of furan acetate is high, which is convenient for industrial production. Detailed Description of the Invention

[0014] The present invention will be further described in detail below through specific examples, but the protection scope of the present invention is not limited to these examples. The experimental methods used in the examples are all conventional methods unless otherwise specified; the materials, reagents, etc. used in the examples can be obtained from commercial channels unless otherwise specified.

[0015] Example 1 Catalyst Preparation: (1) Charge triphenylphosphine (0.13 g) and 2,3,5,6 - tetrafluoroterephthalyl alcohol (0.32 g) into a 50 - mL Schlenk reaction flask, and then add 8 mL of trifluoromethanesulfonic acid. Place the flask in liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it, and slowly warm it to room temperature. Repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then place the flask in an oil bath and heat it to 100 °C for reaction for 24 hours. Then cool the flask to 0 °C, open the reaction flask and quench it with 30 mL of degassed deionized water, filter by suction. The obtained brown solid product is ground and washed once with deionized water, ethanol, tetrahydrofuran, and dichloromethane. The obtained brown solid is dried in vacuo at 50 °C for 24 hours to obtain Polymer 1. (2) Dissolve palladium chloride (0.01 g) in 10 mL of methanol, add Polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double - tube, seal it, and stir at 85 °C for 12 hours. After the reaction is completed, cool the reaction tube to room temperature, collect the solid by suction filtration, and wash it successively with methanol and dichloromethane. Dry it in vacuo at 50 °C for 12 hours to obtain Polymer Catalyst 1.

[0016] Preparation of furan acetate: Weigh 2 g of furfuryl alcohol, 0.5 g of polymer catalyst 1, and 20 mL of methanol, add them to a 100 mL reaction kettle, displace with CO six times, charge 2 MPa of CO, stir and react at 100 °C for 4 hours, cool, add 0.5 g of internal standard (1,4-dioxane), and analyze by gas chromatography. The yield of methyl furanacetate is 85%.

[0017] Structural formula of the product: Characterization data of the product methyl furanacetate: 1 H NMR(400 MHz, CDCl 3 ) δ7.40 (dd, J =1.9, 0.9Hz, 1H), 6.38 (dd, J =3.3, 1.9 Hz, 1H), 6.32 - 6.21 (m, 1H), 3.77 (s, 3H), 3.74(s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 156.57, 148.80, 142.78, 111.68, 109.60,61.30, 54.34 Example 2 Preparation of the catalyst: (1) Put bis(diphenylphosphino)methane (0.2 g) and 2,3,5,6-tetrafluoroterephthalyl alcohol (0.4 g) into a 50 mL Schlenk reaction flask, then add 8 mL of trifluoromethanesulfonic acid. Put the flask into liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it and slowly warm it up to room temperature, repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then put the flask into an oil bath and heat it to 100 °C for reaction for 24 hours, then cool the flask to 0 °C, quench it with 30 mL of degassed deionized water after opening the reaction flask, filter by suction, grind the obtained brown solid product, wash it once with deionized water, ethanol, tetrahydrofuran and dichloromethane, and dry the obtained brown solid in vacuo at 50 °C for 24 hours to obtain polymer 2. (2) Dissolve palladium chloride (0.01 g) in 10 mL of methanol, add polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double-tube and then seal it, stir at 95 °C for 12 hours, after the reaction is completed, cool the reaction tube to room temperature, collect the solid by suction filtration, wash it successively with methanol and dichloromethane, and dry it in vacuo at 50 °C for 12 hours to obtain polymer catalyst 2.

[0018] Preparation of furan acetic acid ester: Weigh 2 g of furfuryl alcohol, 0.5 g of polymer catalyst 2, and 20 mL of ethanol respectively, add them into a 100 mL reaction kettle, displace with CO six times, fill with 2 MPa of CO, stir and react at 100 °C for 4 hours, cool down, add 0.5 g of internal standard (1,4-dioxane), and through gas chromatography analysis, the yield of ethyl furan acetate is 88%.

[0019] Structural formula of the product: Characterization data of the product ethyl furan acetate: 1 H NMR(400 MHz, CDCl 3 ) δ 7.41 (dd, J =1.9,0.9 Hz, 1H), 6.36 (dd, J =3.3, 1.9 Hz, 1H), 6.30 - 6.25 (m, 1H), 4.14 (dd, J = 5.6,11.2 Hz, 2H), 3.74 (s, 2H), 1.25 (t, J = 5.6, Hz, 3H); 13 C NMR (100 MHz, CDCl 3 ) δ156.67, 148.85, 142.82, 111.72, 109.63, 60.30, 34.34, 15.1。

[0020] Example 3 Preparation of the catalyst: (1) Put bis(diphenylphosphino)ethane (0.2 g) and 2,3,5,6-tetrafluoroterephthalic alcohol (0.4 g) into a 50 mL Schlenk reaction flask, then add 8 mL of trifluoromethanesulfonic acid. Put the flask into liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it and slowly warm it up to room temperature, repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then put the flask into an oil bath and heat it to 100 °C for reaction for 24 hours, then cool the flask to 0 °C, open the reaction flask and quench it with 30 mL of degassed deionized water, filter by suction, grind the obtained brown solid product, and wash it once with deionized water, ethanol, tetrahydrofuran and dichloromethane. The obtained brown solid is dried in vacuum at 50 °C for 24 hours to obtain polymer 3. (2) Dissolve palladium acetate (0.01 g) in 10 mL of methanol, add polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double tube and then seal it, stir at 85 °C for 12 hours, after the reaction is completed, cool the reaction tube to room temperature, collect the solid by suction filtration, and wash it successively with methanol and dichloromethane, and dry it in vacuum at 50 °C for 12 hours to obtain polymer catalyst 3.

[0021] Preparation of furan acetic acid ester: Weigh 2 g of furfuryl alcohol, 0.5 g of polymer catalyst 3, and 20 mL of ethanol respectively, add them into a 100 mL reaction kettle, displace with CO six times, fill with 2 MPa of CO, stir and react at 120 °C for 4 hours, cool, add 0.5 g of internal standard (1,4-dioxane), and analyze by gas chromatography. The yield of ethyl furan acetate is 88%.

[0022] Structural formula of the product: Characterization data of the product ethyl furan acetate: 1 H NMR(400 MHz, CDCl 3 ) δ 7.41 (dd, J =1.9,0.9 Hz, 1H), 6.36 (dd, J =3.3, 1.9 Hz, 1H), 6.30 - 6.25 (m, 1H), 4.14 (dd, J = 5.6,11.2 Hz, 2H), 3.74 (s, 2H), 1.25 (t, J = 5.6, Hz, 3H); 13 C NMR (100 MHz, CDCl 3 ) δ156.67, 148.85, 142.82, 111.72, 109.63, 60.30, 34.34, 15.1。

[0023] Example 4 Preparation of the catalyst: (1) Put bis(diphenylphosphino)propane (0.2 g) and 2,3,5,6-tetrafluoroterephthalic alcohol (0.4 g) into a 50 mL Schlenk reaction flask, then add 8 mL of trifluoromethanesulfonic acid. Put the flask into liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it and slowly warm it to room temperature, repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then put the flask into an oil bath and heat it to 100 °C for reaction for 24 hours, then cool the flask to 0 °C, open the reaction flask and quench it with 30 mL of degassed deionized water, filter by suction, grind the obtained brown solid product, and wash it once with deionized water, ethanol, tetrahydrofuran and dichloromethane. The obtained brown solid is dried in vacuum at 50 °C for 24 hours to obtain polymer 4. (2) Dissolve palladium acetate (0.01 g) in 10 mL of methanol, add polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double tube and seal it, stir at 85 °C for 12 hours, after the reaction is completed, cool the reaction tube to room temperature, collect the solid by suction filtration, and wash it successively with methanol and dichloromethane, and dry it in vacuum at 50 °C for 12 hours to obtain polymer catalyst 4.

[0024] Preparation of furan acetic acid ester: Weigh 2 g of furfuryl formate, 0.5 g of polymer catalyst 4, and 20 mL of methanol respectively, add them into a 100 mL autoclave, displace with CO six times, fill with 2 MPa of CO, stir and react at 120 °C for 4 hours, cool, add 0.5 g of internal standard (1,4-dioxane), and analyze by gas chromatography. The yield of methyl furan acetate is 90%.

[0025] Structural formula of the product: Characterization data of the product methyl furan acetate: 1 H NMR(400 MHz, CDCl 3 ) δ7.40 (dd, J =1.9, 0.9Hz, 1H), 6.38 (dd, J =3.3, 1.9 Hz, 1H), 6.32 - 6.21 (m, 1H), 3.77 (s, 3H), 3.74(s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 156.57, 148.80, 142.78, 111.68, 109.60,61.30, 54.34 Example 5 Preparation of the catalyst: (1) Put bis(diphenylphosphino)butane (0.2 g) and 2,3,5,6-tetrafluoroterephthalic alcohol (0.4 g) into a 50 mL Schlenk reaction flask, then add 8 mL of trifluoromethanesulfonic acid. Put the flask into liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it and slowly warm it up to room temperature, repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then put the flask into an oil bath and heat it to 100 °C for reaction for 24 hours, then cool the flask to 0 °C, quench with 30 mL of degassed deionized water after opening the reaction flask, filter by suction, grind the obtained brown solid product, wash it with deionized water, ethanol, tetrahydrofuran and dichloromethane once, and dry the obtained brown solid in vacuum at 50 °C for 24 hours to obtain polymer 5. (2) Dissolve palladium acetate (0.01 g) in 10 mL of methanol, add polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double-tube and seal it, stir at 85 °C for 12 hours, cool the reaction tube to room temperature after the reaction is completed, collect the solid by suction filtration, wash it with methanol and dichloromethane in turn, and dry it in vacuum at 50 °C for 12 hours to obtain polymer catalyst 5.

[0026] Preparation of furfuryl acetate: Weigh 2 g of furfuryl acetate, 0.5 g of polymer catalyst 5, and 20 mL of ethanol respectively, add them into a 100 mL reaction kettle, displace with CO six times, fill with 2 MPa of CO, stir and react at 120 °C for 4 hours, cool down, add 0.5 g of internal standard (1,4-dioxane), and through gas chromatography analysis, the yield of ethyl furanoacetate is 93%.

[0027] Structural formula of the product: Characterization data of the product ethyl furanoacetate: 1 H NMR(400 MHz, CDCl 3 ) δ7.41 (dd, J =1.9, 0.9Hz, 1H), 6.36 (dd, J =3.3, 1.9 Hz, 1H), 6.30 - 6.25 (m, 1H), 4.14 (dd, J = 5.6,11.2 Hz, 2H), 3.74 (s, 2H), 1.25 (t, J = 5.6, Hz, 3H); 13 C NMR (100 MHz, CDCl 3 ) δ156.67, 148.85, 142.82, 111.72,109.63, 60.30, 34.34, 15.1。

[0028] Example 6 Preparation of the catalyst: (1) Put bis(diphenylphosphino)pentane (0.2 g) and 2,3,5,6-tetrafluoroterephthalyl alcohol (0.4 g) into a 50 mL Schlenk reaction flask, then add 8 mL of trifluoromethanesulfonic acid. Put the flask into liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it and slowly warm it up to room temperature, repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then put the flask into an oil bath and heat it to 100 °C for reaction for 24 hours, then cool the flask to 0 °C, after opening the reaction flask, quench it with 30 mL of degassed deionized water, filter by suction, grind the obtained brown solid product, and wash it once with deionized water, ethanol, tetrahydrofuran and dichloromethane. The obtained brown solid is dried in vacuum at 50 °C for 24 hours to obtain polymer 6. (2) Dissolve palladium acetate (0.01 g) in 10 mL of methanol, add polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double manifold and seal it, stir at 85 °C for 12 hours, after the reaction is completed, cool the reaction tube to room temperature, collect the solid by suction filtration, and wash it successively with methanol and dichloromethane, and dry it in vacuum at 50 °C for 12 hours to obtain polymer catalyst 6.

[0029] Preparation of furyl acetate: Weigh 2 g of furfuryl propionate, 0.5 g of polymer catalyst 6, 10 mL of methanol, and 10 mL of tetrahydrofuran, add them into a 100 mL reaction kettle, displace with CO six times, fill with 3 MPa of CO, stir and react at 150 °C for 4 hours, cool down, add 0.5 g of internal standard (1,4-dioxane), and through gas chromatography analysis, the yield of methyl furylacetate is 91%.

[0030] Structural formula of the product: Characterization data of the product methyl furylacetate: 1 H NMR (400 MHz, CDCl 3 ) δ7.40 (dd, J J = 1.9, 0.9Hz, 1H), 6.38 (dd, J J = 3.3, 1.9 Hz, 1H), 6.32 - 6.21 (m, 1H), 3.77 (s, 3H), 3.74(s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ156.57, 148.80, 142.78, 111.68, 109.60,61.30, 54.34 Example 7 Preparation of the catalyst: (1) Load bis(diphenylphosphino)hexane (0.2 g) and 2,3,5,6-tetrafluoroterephthalyl alcohol (0.4 g) into a 50 mL Schlenk reaction flask, then add 8 mL of trifluoromethanesulfonic acid. Place the flask in liquid nitrogen, use a vacuum pump to evacuate the air in the flask, seal it and slowly warm it up to room temperature, repeat this step twice to remove air as much as possible. Ultrasonic the sealed reaction flask for 10 minutes, then place the flask in an oil bath and heat it to 100 °C for reaction for 24 hours, then cool the flask to 0 °C, after opening the reaction flask, quench it with 30 mL of degassed deionized water, filter by suction, grind the obtained brown solid product, and wash it once with deionized water, ethanol, tetrahydrofuran and dichloromethane. The obtained brown solid is dried in vacuum at 50 °C for 24 hours to obtain polymer 7. (2) Dissolve palladium acetate (0.01 g) in 10 mL of methanol, add polymer 1 (0.2 g), displace the air in the reaction tube with nitrogen through a double manifold and then seal it, stir at 85 °C for 12 hours, after the reaction is completed, cool the reaction tube to room temperature, collect the solid by suction filtration, and wash it successively with methanol and dichloromethane, and dry it in vacuum at 50 °C for 12 hours to obtain polymer catalyst 7.

[0031] Preparation of furfuryl acetate: Weigh 2 g of furfuryl acetate, 0.5 g of polymer catalyst 7, and 20 mL of methanol respectively, add them into a 100 mL reaction kettle, displace with CO six times, fill with 1 MPa of CO, stir and react at 130 °C for 4 hours, cool down, add 0.5 g of internal standard (1,4-dioxane), and through gas chromatography analysis, the yield of methyl furanoacetate is 90%.

[0032] Structural formula of the product: Characterization data of the product methyl furanoacetate: 1 H NMR(400 MHz, CDCl 3 ) δ7.40 (dd, J =1.9, 0.9Hz, 1H), 6.38 (dd, J =3.3, 1.9 Hz, 1H), 6.32 - 6.21 (m, 1H), 3.77 (s, 3H), 3.74(s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ156.57, 148.80, 142.78, 111.68, 109.60,61.30, 54.34。

[0033] Example 8 Reuse of the polymer catalyst: Weigh 2 g of furfuryl acetate, 0.5 g of polymer catalyst 7, and 20 mL of methanol respectively, add them into a 100 mL reaction kettle, displace with CO six times, fill with 2 MPa of CO, stir and react at 130 °C for 4 hours, cool down, add 0.5 g of internal standard (1,4-dioxane), and through gas chromatography analysis, the yield of methyl furanoacetate is shown in Table 1, recorded as the result of the 1st use; Centrifuge the reaction solution to separate, and put the obtained catalyst back into the above reaction kettle, then add 2 g of furfuryl acetate and 20 mL of methanol in turn, displace with CO six times, fill with 2 MPa of CO, stir and react at 130 °C for 4 hours, cool down, add 0.5 g of internal standard (1,4-dioxane), and through gas chromatography analysis, the yield of methyl furanoacetate is shown in Table 1, recorded as the result of the 2nd use; Repeat the above steps to obtain the results of the 3rd, 4th, 5th, and 6th reuse of the catalyst respectively. It can be seen from the results in Table 1 that the polymer catalyst of the present invention has good recycling stability.

[0034]

Claims

1. A method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives, comprising adding a raw material of furfuryl alcohol or its derivatives, a polymer catalyst containing an aryl phosphine ligand and a palladium salt into an organic solvent, introducing carbon monoxide gas, and performing carbonylation reaction at a temperature of 30-200° C. and a pressure of 0.1-6 MPa for 0.5-20 hours, wherein the reaction product is a furanacetic acid ester compound; The structural formula of furfuryl alcohol or its derivatives is: in, The substituents R1 and R2 are selected from hydrogen, alkoxy, alkyl, carboxyl, aldehyde or hydroxyl; The preparation of the polymer catalyst containing an aryl phosphine ligand and a palladium salt includes two preparation processes; The first preparation process comprises the following steps: (1) Under vacuum conditions, using an aryl phosphine ligand and 2,3,5,6-tetrafluorophenylenedimethanol as raw materials, trifluoromethanesulfonic acid as a catalyst and a solvent, a polymerization reaction is carried out at 50-160° C. for 4-48 hours. After the reaction is completed, the reaction system is cooled and quenched with water. The insoluble solid is filtered, washed, and dried to obtain a phosphorus-containing polymer carrier; the molar ratio of the aryl phosphine ligand to 2,3,5,6-tetrafluorophenylenedimethanol is 1:1.5-1:8; (2) stirring the obtained phosphorus-containing polymer support and palladium salt in methanol at 50-120° C. for 6-24 hours, filtering, washing and drying to obtain a polymer catalyst containing an aromatic phosphine ligand and a palladium salt; the mass ratio of the phosphorus-containing polymer support to the palladium salt is 99.9:0.1-95:5; The second preparation process comprises the following steps: (1) Under a nitrogen atmosphere, a palladium salt and an aryl phosphine ligand are heated in a methanol solvent, and stirred and refluxed at 50-120° C. for 2-24 hours. After the reaction is completed, the reaction solution is allowed to stand, and a palladium-phosphine complex is obtained by suction filtration, washing, and drying. The molar ratio of the palladium salt to the aryl phosphine ligand is 1:1-1:

8. (2) Under vacuum conditions, a palladium-phosphine complex and 2,3,5,6-tetrafluorophenylenedimethanol are used as raw materials, trifluoromethanesulfonic acid is used as a catalyst and a solvent, and a polymerization reaction is carried out at 50-160° C. for 4-48 hours. After the reaction is completed, the reaction system is cooled and quenched with water. The insoluble solid is filtered, washed, and dried to obtain a polymer catalyst containing an aromatic phosphine ligand and a palladium salt; the molar ratio of the palladium-phosphine complex to 2,3,5,6-tetrafluorophenylenedimethanol is 1:1.5-1:

8.

2. The method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives as claimed in claim 1, characterized in that: The palladium salt is selected from at least one of palladium acetate, palladium nitrate, palladium chloride, palladium bromide, palladium carbon, and palladium acetylacetonate.

3. The method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives as claimed in claim 1, characterized in that: The aromatic phosphine ligand is selected from at least one of triphenylphosphine, 1,1'-bis(diphenylphosphino)ferrocene, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,5-bis(diphenylphosphino)pentane, 1,6-bis(diphenylphosphino)hexane, tri-tert-butylphosphine, tricyclohexylphosphine, 1,2-bis(diphenylphosphino)benzene, 1,1'-binaphthyl-2,2'-bisdiphenylphosphine, bis(2-diphenylphosphinophenyl)ether, tri-p-phenylmethylphosphine, tri(4-fluorophenyl)phosphine, tri(pentafluorophenyl)phosphine, tri(4-chlorophenyl)phosphine, and tri(2-furan)phosphine.

4. The method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives as claimed in claim 1, characterized in that: The mass ratio of furfuryl alcohol and its derivatives to the polymer catalyst containing an aromatic phosphine ligand and a palladium salt is 1:0.05-1:

1.

5. The method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives as claimed in claim 1, characterized in that: The organic solvent is at least one of tetrahydrofuran, ethylene dichloride, methanol, ethanol, propanol, butanol, toluene and cyclohexane.

6. The method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives as claimed in claim 1, characterized in that: The polymer catalyst containing the aryl phosphine ligand and the palladium salt can be recycled after being separated by simple filtration, and after being recycled for 5 times, the yield of furanacetate is maintained above 90%.

7. The method for synthesizing furanacetic acid ester compounds by carbonylation of furfuryl alcohol and its derivatives as claimed in claim 1, characterized in that: The carbonylation reaction temperature is 100-150° C., the reaction pressure is 1-3 MPa, and the reaction time is 4-12 hours.

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