A photocatalytic synthesis method for 2(5H)-furanone compounds

Abstract

The present invention discloses a method for the photocatalytic synthesis of 2(5H)-furanone compounds. The photocatalytic synthesis method comprises the following steps: furfural and its derivatives are subjected to a selective oxidation reaction under the catalysis of a photocatalyst to obtain the obtained compounds; the structural formula of furfural and its derivatives is shown in Formula I, and the structural formula of the 2(5H)-furanone compounds is shown in Formula II; the photocatalyst is an inorganic semiconductor photocatalyst, and is a composite material of one or two of the following oxyhydroxy compounds: AlOOH, ScOOH, YOOH, VOOH, CrOOH, GaOOH, MnOOH, FeOOH, CoOOH, and InOOH. The present invention uses furfural or furfural derivatives as raw materials, selectively oxidizes them in the presence of an inorganic semiconductor photocatalyst, and obtains 2(5H)-furanone compounds. This method realizes the first preparation of 2(5H)-furanone compounds by catalyzing the selective oxidation of biomass-based furfural and its derivatives on an inorganic semiconductor photocatalyst. After the reaction is completed, the catalyst is easily separated and can be recycled and reused, showing good application prospects. #imgabs0#

Description

Technical Field

[0001] The invention relates to a photocatalytic synthesis method of 2(5H)-furanone compounds, belonging to the technical field of organic synthesis. Background Art

[0002] 2(5H)-furanone compounds have been studied as a key synthon in the total synthesis of natural products and drugs. Due to their biological activities such as antibacterial, anti-inflammatory, antiviral, and antitumor, 2(5H)-furanone compounds can be used in the preparation of pesticides, plant growth regulators, quick-drying coatings, prostaglandins, alkaloids, etc. In addition, the α,β-unsaturated aldehyde structure of 2(5H)-furanone compounds allows them to be used as a replacement for acrylates and used as lactone monomers in the synthesis of polymeric materials. Currently, only reagent-sized quantities of 2(5H)-furanone compounds are available on the market, and they are expensive. At present, the main production process of 2(5H)-furanone compounds is to photooxidize furfural and its derivatives with photosensitizers. This method faces the problem of difficult recycling of photosensitizers and requires subsequent treatment such as activated carbon decolorization (Environ.Sci.Pollut.Res.Int.2021,28,28911-28925). Therefore, it is necessary to provide a new synthesis method of 2(5H)-furanone compounds. Summary of the Invention

[0003] The present invention aims to provide a method for synthesizing 2(5H)-furanone compounds. The method adopts a one-step photocatalytic oxidation method to directly oxidize furfural and its derivatives to obtain 2(5H)-furanone compounds. The method has the advantages of mild conditions, high selectivity, and easy recycling of the catalyst.

[0004] The synthesis method of the invention adopts an inorganic semiconductor photocatalyst and uses biomass-based platform compound furfural and its derivatives as raw materials.

[0005] Specifically, the photocatalytic synthesis method of 2(5H)-furanone compounds provided by the present invention comprises the following steps:

[0006] Under the catalysis of photocatalyst, furfural and its derivatives undergo selective oxidation reaction to obtain 2(5H)-furanone compounds;

[0007] The structural formula of furfural and its derivatives is shown in Formula I:

[0008]

[0009]

[0010] The structural formula of the 2(5H)-furanone compound is shown in Formula II:

[0011]

[0012] In Formula I and Formula II, R1 is -H, -COOH, an alkyl group having 1 to 5 carbon atoms, or an alkyl alcohol having 1 to 5 carbon atoms, R2 is -H, an alkyl group having 1 to 5 carbon atoms, or an alkyl alcohol having 1 to 5 carbon atoms, and R3 is -H, an alkyl group having 1 to 5 carbon atoms, or an alkyl alcohol having 1 to 5 carbon atoms;

[0013] Preferably, the number of carbon atoms of the alkyl group or the alkyl alcohol is 1 to 3;

[0014] In formula I, R4 is -H or -OH;

[0015] The photocatalyst is an inorganic semiconductor photocatalyst, which is a composite material of one or two of the following oxyhydroxides. When it is a composite material of two components, the molar ratio of the two components is 5-1:1-5:

[0016] AlOOH, ScOOH, YOOH, VOOH, CrOOH, GaOOH, MnOOH, FeOOH, CoOOH and InOOH.

[0017] The inorganic semiconductor photocatalytic material used in the present invention has the advantages of high chemical stability, easy reuse, simple synthesis process, low price, and environmental friendliness. It can replace the photosensitizer to efficiently and selectively oxidize and prepare 2(5H)-furanone chemicals.

[0018] The furfural and its derivatives used in the present invention are preferably compounds represented by the following structural formula:

[0019]

[0020] In the photocatalytic synthesis method of the present invention, the dosage of the photocatalyst is: 10 to 100 mg of the photocatalyst is added to 1 mmol of the furfural and its derivatives.

[0021] In the photocatalytic synthesis method of the present invention, the solvent used in the selective oxidation reaction is tetrahydrofuran, 1,4-dioxane, toluene, cyclohexane, n-hexane, methanol, ethanol or water, and the amount of the solvent used is 10-20 mL / 1 mmol of furfural and its derivatives.

[0022] In the photocatalytic synthesis method of the present invention, the selective oxidation reaction is carried out under normal pressure, at a temperature of 10 to 80° C., and for a time of 1 to 24 hours.

[0023] In the photocatalytic synthesis method of the present invention, the selective oxidation reaction adopts a xenon lamp light source with a power of 100 to 400W.

[0024] The present invention provides a method for photocatalytically preparing 2(5H)-furanone compounds, which uses furfural or furfural derivatives as raw materials, and selectively oxidizes them in the presence of an inorganic semiconductor photocatalyst to obtain 2(5H)-furanone compounds. The present invention realizes for the first time the selective oxidation of biomass-based furfural and its derivatives on an inorganic semiconductor photocatalyst to prepare 2(5H)-furanone compounds; the catalyst used has high activity and high product selectivity. The use of biomass-based compounds as raw materials to prepare 2(5H)-furanone compounds meets the requirements of sustainable development and green chemistry. The 2(5H)-furanone compounds of the method of the present invention have high selectivity, which facilitates the separation and purification of the product. After the reaction of the synthesis method of the present invention is completed, the catalyst is easy to separate and can be recycled and reused, and has good application prospects. DETAILED DESCRIPTION

[0025] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0026] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0027] In the following examples, the conversion rate refers to (the amount of reactants converted / the total amount of reactants)×100%.

[0028] In the following examples, molar selectivity refers to (the number of moles of target product) / (the number of moles of reactant converted)×100%.

[0029] In the following examples, the conditions for liquid chromatography analysis are as follows:

[0030] The liquid phase products were analyzed and detected on a Shimadzu liquid chromatography LC20A. The analytical column used was a Shodex Sugar 1011 sugar column, the mobile phase was a 1 wt% dilute sulfuric acid solution, and the flow rate was 1.0 mL min -1 , the column temperature was set at 50 °C.

[0031] Example 1:

[0032] Weigh the corresponding mass of Al(NO3)3 and Sc(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220℃ for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110℃ for 8 hours to obtain AlOOH-ScOOH composite material (ratio of 5:1).

[0033] The photocatalytic oxidation of furfural was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 10 mg of catalyst, and 10 mL of deionized water were added to a 50 mL reactor and reacted at 20°C in a circulating water bath. The reactor was irradiated with a 300W xenon lamp and the reaction was completed after 12 hours of rapid stirring. Liquid chromatography analysis revealed a furfural conversion of 99.5%, a molar selectivity for 5-hydroxy-2(5H)-furanone of 96.6%, and formic acid as the remaining byproduct.

[0034] Example 2:

[0035] Weigh the corresponding mass of Y(NO3)3 and Sc(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain ScOOH-YOOH composite material (ratio is 1:1).

[0036] The photocatalytic oxidation of furoic acid was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 25 mg of catalyst, and 20 mL of methanol were added to a 50 mL reactor and reacted at 25°C in a circulating water bath. The reactor was irradiated with a 200W xenon lamp and the reaction was completed after 8 hours of rapid stirring. Liquid chromatography analysis showed 100% furoic acid conversion, 93.0% molar selectivity for 5-hydroxy-2(5H)-furanone, and formic acid as the remaining byproduct.

[0037] Example 3:

[0038] Weigh the corresponding mass of V(NO3)3 and dissolve it in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix well and put it in an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain VOOH material.

[0039] The photocatalytic oxidation of 5-hydroxymethylfurfural was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 20 mg of catalyst, and 10 mL of ethanol were added to a 50 mL reactor and reacted at 40°C in a circulating water bath. The reactor was irradiated with a 400W xenon lamp and the reaction was completed after 1 hour of rapid stirring. Liquid chromatography analysis revealed a 98.7% conversion of 5-hydroxymethylfurfural and an 89.2% molar selectivity for 5-hydroxymethyl-5-hydroxy-2(5H)-furanone. The remaining byproduct was formic acid.

[0040] Example 4:

[0041] Weigh the corresponding mass of Y(NO3)3 and V(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain a YOOH-VOOH composite material (ratio of 1:5).

[0042] The photocatalytic oxidation of 5-hydroxymethylfuroic acid was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 50 mg of catalyst, and 15 mL of deionized water were added to a 50 mL reactor and reacted at 80°C in a circulating water bath. The reactor was irradiated with a 300W xenon lamp and the reaction was completed after 2 hours of rapid stirring. Liquid chromatography analysis revealed a 94.3% conversion of 5-hydroxymethylfuroic acid and a 92.7% molar selectivity for 5-hydroxymethyl-5-hydroxy-2(5H)-furanone. The remaining byproduct was formic acid.

[0043] Example 5:

[0044] Weigh the corresponding mass of Cr(NO3)3 and Ga(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain a CrOOH-GaOOH composite material (ratio of 3:1).

[0045] The photocatalytic oxidation of 5-methylfurfural was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 100 mg of catalyst, and 20 mL of tetrahydrofuran were added to a 50 mL reactor and reacted at 10°C in a circulating water bath. The reactor was irradiated with a 100W xenon lamp and the reaction was completed after 24 hours of rapid stirring. Liquid chromatography analysis revealed a 99.4% conversion of 5-methylfurfural and an 86.8% molar selectivity for 5-methyl-5-hydroxy-2(5H)-furanone. The remaining byproduct was formic acid.

[0046] Example 6:

[0047] Weigh the corresponding mass of Mn(NO3)3 and Fe(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain a MnOOH-FeOOH composite material (ratio of 2:1).

[0048] The photocatalytic oxidation of furandicarboxylic acid was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 50 mg of catalyst, and 10 mL of 1,4-dioxane were added to a 50 mL reactor and reacted at 30°C in a circulating water bath. The reactor was irradiated with a 200 W xenon lamp and reacted with rapid stirring for 12 hours. Liquid chromatography analysis revealed a 94.8% conversion of furandicarboxylic acid and an 85.3% molar selectivity for 2-hydroxy-5-oxo-2,5-dihydrofuran-2-carboxylic acid. The remaining byproduct was formic acid.

[0049] Example 7:

[0050] Weigh the corresponding mass of Co(NO3)3 and Fe(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain FeOOH-CoOOH composite material (ratio of 1:4).

[0051] The photocatalytic oxidation of 4-hydroxymethylfurfural was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 25 mg of catalyst, and 15 mL of toluene were added to a 50 mL reactor and reacted at 60°C in a circulating water bath. The reactor was irradiated with a 300W xenon lamp and the reaction was completed after 16 hours of rapid stirring. Liquid chromatography analysis revealed a 96.1% conversion of 4-hydroxymethylfurfural and a 94.8% molar selectivity for 4-hydroxymethyl-5-hydroxy-2(5H)-furanone. The remaining byproduct was formic acid.

[0052] Example 8:

[0053] Weigh the corresponding mass of Co(NO3)3 and Ga(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain a CoOOH-GaOOH composite material (ratio of 1:2).

[0054] The photocatalytic oxidation of 4-methylfurfural was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 1 mmol of substrate, 50 mg of catalyst, and 10 mL of cyclohexane were added to a 50 mL reactor and reacted at 40°C in a circulating water bath. The reactor was irradiated with a 400W xenon lamp and the reaction was completed after 10 hours of rapid stirring. Liquid chromatography analysis revealed 100% conversion of 4-methylfurfural, 93.5% molar selectivity for 4-methyl-5-hydroxy-2(5H)-furanone, and formic acid as the remaining byproduct.

[0055] Example 9:

[0056] Weigh the corresponding mass of Co(NO3)3 and In(NO3)3 respectively and dissolve them in 50 mL of deionized water. After stirring to dissolve, add NaOH solution, mix evenly and put into an oven. Keep it at 220°C for 12 hours. Filter the obtained product and wash it with deionized water and ethanol three times respectively. Then dry it in an oven at 110°C for 8 hours to obtain a CoOOH-InOOH composite material (ratio of 1:1).

[0057] The photocatalytic oxidation of 3-methylfurfural was carried out in a photocatalytic reactor equipped with a circulating water bath at 600 rpm. 2 mmol of substrate, 30 mg of catalyst, and 20 mL of n-hexane were added to a 50 mL reactor and reacted at 20°C in a circulating water bath. The reactor was irradiated with a 300W xenon lamp and the reaction was completed after 4 hours of rapid stirring. Liquid chromatography analysis revealed a 98.6% conversion of 3-methylfurfural and an 87.7% molar selectivity for 3-methyl-5-hydroxy-2(5H)-furanone. The remaining byproduct was formic acid.

Claims

1. A photocatalytic synthesis method of 2(5H)-furanone compounds, comprising the following steps: Under the catalysis of photocatalyst, furfural and its derivatives undergo selective oxidation reaction to obtain 2(5H)-furanone compounds; The structural formula of furfural and its derivatives is shown in Formula I: The structural formula of the 2(5H)-furanone compound is shown in Formula II: In Formula I and Formula II, R1 is -H, -COOH, an alkyl group having 1 to 5 carbon atoms, or an alkyl alcohol having 1 to 5 carbon atoms, R2 is -H, an alkyl group having 1 to 5 carbon atoms, or an alkyl alcohol having 1 to 5 carbon atoms, and R3 is -H, an alkyl group having 1 to 5 carbon atoms, or an alkyl alcohol having 1 to 5 carbon atoms; In formula I, R4 is -H or -OH; The photocatalyst is an inorganic semiconductor photocatalyst, which is a composite material of one or two of the following oxyhydroxides: AlOOH, ScOOH, YOOH, VOOH, CrOOH, GaOOH, MnOOH, FeOOH, CoOOH and InOOH.

2. The photocatalytic synthesis method according to claim 1, characterized in that: The dosage of the photocatalyst is as follows: 10 to 100 mg of the photocatalyst is added to 1 mmol of the furfural and its derivatives.

3. The photocatalytic synthesis method according to claim 1 or 2, characterized in that: The solvent used in the selective oxidation reaction is tetrahydrofuran, 1,4-dioxane, toluene, cyclohexane, n-hexane, methanol, ethanol or water.

4. The photocatalytic synthesis method according to claim 1 or 2, characterized in that: The selective oxidation reaction is carried out under normal pressure, at a temperature of 10 to 80° C., for 1 to 24 hours.

5. The photocatalytic synthesis method according to claim 1 or 2, characterized in that: The selective oxidation reaction adopts a xenon lamp light source with a power of 100 to 400W.

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