A photocatalytic synthesis method of 2,5-diphenylfuran-3-carboxylate compounds

Abstract

The application discloses a kind of 2,5-diphenyl furan-3-carboxylate compound photocatalytic synthesis method, it includes the following steps: α, β-unsaturated ketone compound, α-diazo iodonium salt and catalyst are dispersed in organic solvent, then coupling cyclization reaction is carried out under light, obtains 2,5-diphenyl furan-3-carboxylate compound.The 2,5-diphenyl furan-3-carboxylate compound photocatalytic synthesis method of the application has the advantages that raw material is cheap and easy to obtain, simple and efficient, reaction condition is mild, reaction is not sensitive to air and water, atom economy is high, product is easy to purify, green and economic, etc., is suitable for large-scale industrial production.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, specifically to a photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters. Background Technology

[0002] 2,5-Diphenylfuran-3-carboxylic acid esters contain a furan ring, a benzene ring, and an ester group. They possess a unique conjugated structure and electronic effects, exhibiting excellent performance in pharmaceuticals, materials, and fine chemicals, and showing great promise for industrial applications. For example, in the pharmaceutical field, 2,5-diphenylfuran-3-carboxylic acid esters can act as antibacterial, anti-inflammatory, and antitumor active ingredients, participating in the regulation of enzyme activity and receptor binding processes in vivo. In the materials field, they can be used in the preparation of organic light-emitting diodes (OLEDs), fluorescent probes, and organic semiconductor materials. In the fine chemical field, they can serve as intermediates for the synthesis of high-performance coatings, polymer monomers, and fragrance precursors.

[0003] Currently, the main methods for synthesizing 2,5-diphenylfuran-3-carboxylic acid esters include the following categories: 1) Synthetic method based on Paal-Knorr furan synthesis reaction: 1,4-dicarbonyl compound is used as raw material to generate furan ring by intramolecular dehydration cyclization under acid catalysis. However, this method requires multiple steps to synthesize 1,4-dicarbonyl raw material (e.g., 2,5-diphenyl-3-oxovalerate ester). The raw material preparation process is cumbersome and costly. Furthermore, the subsequent synthesis of 2,5-diphenylfuran-3-carboxylic acid esters under acid catalysis is prone to ester hydrolysis or phenyl substituent rearrangement. The reaction selectivity is poor, and the yield of the target product is usually less than 50%, which is difficult to meet the needs of industrial production. 2) Transition metal-catalyzed cyclization reaction method: Using transition metals such as palladium (Pd) and copper (Cu) as catalysts, a furan ring skeleton is constructed through the cyclization coupling reaction of alkynes and alcohols (e.g., using phenylacetylene and α-hydroxy ketone as raw materials to generate 2,5-diphenylfuran intermediate under Pd(PPh3)4 catalysis, followed by esterification to introduce a carboxylic acid ester group). However, the transition metal catalysts used in this method are expensive and tend to remain in the product (the pharmaceutical field has strict requirements for metal residue levels, which must be below 10 ppm). The subsequent purification process is complex, and the reaction needs to be carried out at high temperature (120℃~150℃) and under inert gas protection, which is demanding and energy-intensive. In addition, the substrate universality is poor (when the phenyl group has strong electron-withdrawing groups such as nitro or cyano, the reaction is prone to termination, making it impossible to efficiently synthesize multi-substituted derivatives). 3) Multi-component tandem reaction method: Using aldehydes, ketones, diethyl malonate, etc. as raw materials, 2,5-diphenylfuran-3-carboxylic acid esters are synthesized through Knoevenagel condensation-cyclization tandem reaction. However, this method requires the use of excessive organic bases (e.g., piperidine, triethylamine) as catalysts, which will generate a large amount of alkaline wastewater, causing serious environmental pollution. Moreover, the reaction generates a large number of byproducts (e.g., monosubstituted furans, transesterification products), making the separation and purification of the target product difficult, and the purity of the product is difficult to meet the application standards in the pharmaceutical or materials fields (purity must be ≥98%).

[0004] In summary, the existing methods for synthesizing 2,5-diphenylfuran-3-carboxylic acid esters all have significant shortcomings and cannot fully meet the needs of practical applications.

[0005] Therefore, it is of great significance to develop a method for synthesizing 2,5-diphenylfuran-3-carboxylic acid esters that uses inexpensive and readily available raw materials, has mild reaction conditions, uses inexpensive and environmentally friendly catalysts, exhibits high reaction selectivity, and is suitable for industrial production. Summary of the Invention

[0006] The purpose of this invention is to provide a photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters.

[0007] The technical solution adopted in this invention is: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: dispersing α,β-unsaturated ketones, α-diazoiodonium salts, and catalysts in an organic solvent, followed by a coupling cyclization reaction under light irradiation. The α,β-unsaturated ketone is... In the formula, R 1 Selected from methyl, methoxy, -F, -Cl, -Br or trifluoromethyl, R 2 Selected from -H, methyl, or -F, R 3 Selected from -H, methyl, -F, -Br, or methoxy, α-diazoiodomonium salts are... 2,5-Diphenylfuran-3-carboxylic acid esters were obtained.

[0008] Note: The structural formulas of 2,5-diphenylfuran-3-carboxylic acid esters are as follows: .

[0009] Preferably, the R 2 It is -H.

[0010] Preferably, the R 3 It is -H.

[0011] Preferably, the molar ratio of the α,β-unsaturated ketone compound to the α-diazoiodonium salt is 1:2 to 4.

[0012] Preferably, the α-diazo iodoium salt is prepared by a method comprising the following steps: dissolving iodophenyl diacetic acid in a solvent and placing it in an ice bath, then adding trimethylsilyl trifluoromethanesulfonate, then adding ethyl diazonate in batches, then reacting at room temperature, and then separating and purifying the product.

[0013] Preferably, the molar ratio of iodophenyl diacetic acid, trimethylsilyl trifluoromethanesulfonate, and ethyl diazonate is 1:0.8-1.2:2-3.

[0014] Preferably, the solvent is dichloromethane.

[0015] Preferably, the reaction time is 40 min to 80 min.

[0016] Preferably, the molar ratio of the α,β-unsaturated ketone compound to the catalyst is 1:0.01 to 0.02.

[0017] Preferably, the catalyst is at least one of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate), tris(4,7-biphenyl-1,10-o-phenanthroline)ruthenium dichloride, and tris[4,4'-bis(tert-butyl)-2,2'-bipyridine]ruthenium hexafluorophosphate(II).

[0018] More preferably, the catalyst is tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate).

[0019] Preferably, the ratio of the α,β-unsaturated ketone compound to the organic solvent is 1 mmol: 5 mL to 50 mL.

[0020] Preferably, the organic solvent is at least one of N,N-dimethylformamide, N-methylpyrrolidone, and N,N-dimethylacetamide.

[0021] Preferably, the coupling cyclization reaction is carried out under blue light irradiation and at a temperature of 10°C to 70°C.

[0022] More preferably, the coupling cyclization reaction is carried out under conditions of blue light irradiation at a wavelength of 456 nm and a temperature of 10°C to 70°C.

[0023] Preferably, the coupling cyclization reaction takes place over a period of 1 hour to 24 hours.

[0024] Preferably, the reaction products are subjected to column chromatography after the coupling cyclization reaction is completed.

[0025] Preferably, the eluent used in the column chromatography consists of petroleum ether and ethyl acetate.

[0026] The beneficial effects of this invention are: the photocatalytic synthesis method of 2,5-diphenylfuran-3-carboxylic acid esters of this invention has the advantages of inexpensive and readily available raw materials, simplicity and efficiency, mild reaction conditions, insensitivity to air and water, high atom economy, easy product purification, and green economy, making it suitable for large-scale industrial production. Attached Figure Description

[0027] Figure 1 The image shows the 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 1.

[0028] Figure 2 This is the carbon NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 1.

[0029] Figure 3 The image shows the 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 2.

[0030] Figure 4 This is the carbon NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 2.

[0031] Figure 5 The image shows the 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 3.

[0032] Figure 6 This is the carbon NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 3.

[0033] Figure 7 The image shows the 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 4.

[0034] Figure 8 This is the carbon NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 4.

[0035] Figure 9 The image shows the 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 5.

[0036] Figure 10 This is the carbon NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 5.

[0037] Figure 11 The image shows the 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 6.

[0038] Figure 12 This is the carbon NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in Example 6. Detailed Implementation

[0039] The present invention will be further explained and described below with reference to specific embodiments.

[0040] The α,β-unsaturated ketones in Examples 1–6 were prepared using the following method (Reference: Chia-Jui Lee, Tzu-Hsiu Chang, Jhen-Kuei Yu, Ganapuram Madhusudhan Reddy, Ming-YuHsiao, and Wenwei Lin, Synthesis of Functionalized Furans via Chemoselective Reduction / Wittig Reaction Using Catalytic Triethylamine and Phosphine. [J] Org. Lett. 2016, 18, 3758-3761): 11 mmol of benzaldehyde and 10 mmol of acetophenone were dissolved in a mixed solvent consisting of 14 mL of ethanol and 7 mL of water. 0.2 g of NaOH was then added, and the mixture was stirred at room temperature for 1 h. The reaction solution was then poured into water containing crushed ice, filtered, and the solid (light yellow / yellow) was washed with an aqueous ethanol solution (ethanol:water volume ratio of 2:1) to obtain the α,β-unsaturated ketones.

[0041] The synthesis reactions of α,β-unsaturated ketones are as follows: .

[0042] The preparation methods of α-diazoiodoium salts in Examples 1-6 are as follows (Reference: Chem. Eur. J. 2025,31, e202403509): 5 mmol of iodophenyl diacetic acid was dissolved in 10 mL of dichloromethane (analytical grade) and placed in an ice bath. Then, 5 mmol of trimethylsilyl trifluoromethanesulfonate was added, followed by the addition of 12 mmol of ethyl diazonate in portions over 10 min. The ice bath was then removed until nitrogen gas was observed to escape. The mixture was then stirred at room temperature for 1 h, and the solvent was removed under vacuum. The crude product was then dissolved in a diethyl ether-dichloromethane mixed solvent (diethyl ether to dichloromethane volume ratio of 5:1) and recrystallized at -30 °C for 12 h. After filtration, the solid was washed with 200 mL of diethyl ether to obtain α-diazoiodoium salts.

[0043] The synthesis reaction of α-diazo iodine salt is as follows: .

[0044] Example 1: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: 44.4 mg (0.2 mmol) of (E)-1-phenyl-3-(p-tolyl)prop-2-en-1-one, 280 mg (0.6 mmol) of α-diazoiodonium salt and 1.72 mg (0.002 mmol) of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate) salt were added to 1 mL of N,N-dimethylformamide (analytical grade). The mixture was then irradiated with blue light at a wavelength of 456 nm and stirred at 10 °C for 1 h. The temperature was then raised to 70 °C and stirred for another 1 h. After cooling to room temperature, the solvent was removed by rotary evaporation, followed by column chromatography. The eluent for column chromatography consisted of petroleum ether and ethyl acetate in a volume ratio of 100:1, yielding 43.4 mg of 2,5-diphenylfuran-3-carboxylic acid ester compounds (yield: 71%).

[0045] The 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in this embodiment is shown below. Figure 1 As shown, the carbon NMR spectrum is as follows: Figure 2 As shown.

[0046] Spectral analysis: 1 H NMR (500 MHz, CDCl3): δ 7.97 (d, J = 8.3 Hz, 2H), 7.75 - 7.69 (m, 2H), 7.40 (t, J = 7.8 Hz, 2H), 7.33 - 7.24 (m, 3H), 7.07 (s, 1H), 4.32 (q, J = 7.1 Hz,2H), 2.40 (s, 3H), 1.36 (t, J = 7.1 Hz, 3H).

[0047] 13 C NMR (126 MHz, CDCl3): δ 163.65, 156.85, 152.03, 139.55, 129.91,128.87, 128.80, 128.34, 127.97, 127.05, 123.97, 115.26, 107.89, 60.58, 21.50,14.32.

[0048] HR-MS: Theoretical value [M+H]+ :C 20 H 19 O3: 307.1329, measured value: 307.1324.

[0049] In summary, the structural formula of the 2,5-diphenylfuran-3-carboxylic acid ester compound (CAS No.: 215812-62-7) synthesized in this embodiment is as follows: .

[0050] Example 2: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: 47.6 mg (0.2 mmol) of (E)-3-(4-methoxyphenyl)-1-phenyl-2-en-1-one, 280 mg (0.6 mmol) of α-diazoiodomonium salt, and 1.72 mg (0.002 mmol) of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate) salt were added to 1 mL of N,N-dimethylformamide (analytical grade). The mixture was then irradiated with blue light at a wavelength of 456 nm and stirred at 10 °C for 1 h. The temperature was then raised to 70 °C and stirred for another 1 h. After cooling to room temperature, the solvent was removed by rotary evaporation, followed by column chromatography. The eluent for column chromatography consisted of petroleum ether and ethyl acetate in a volume ratio of 100:1, yielding 23.8 mg of 2,5-diphenylfuran-3-carboxylic acid ester compounds (yield: 37%).

[0051] The 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in this embodiment is shown below. Figure 3 As shown, the carbon NMR spectrum is as follows: Figure 4 As shown.

[0052] Spectral analysis: 1 H NMR (500 MHz, CDCl3): δ 8.06 (d, J = 8.9 Hz, 2H), 7.76 - 7.69 (m, 2H),7.41 (t, J = 7.7 Hz, 2H), 7.30 (s, 1H), 7.06 (s, 1H), 6.98 (d, J = 8.9 Hz, 2H), 4.33 (d, J = 7.1 Hz, 2H), 3.87 (s, 3H), 1.37 (t, J = 7.2 Hz, 3H).

[0053] 13C NMR (126 MHz, CDCl3): δ 163.73, 160.49, 156.84, 151.70, 129.99, 129.94, 128.79, 127.88, 123.90, 122.52, 114.53, 113.59, 107.83, 60.53, 55.36,14.33.

[0054] HR-MS: Theoretical value [M+H] + :C 20 H 18 O4: 323.1278, Measured value: 323.1281.

[0055] In summary, the structural formula of the 2,5-diphenylfuran-3-carboxylic acid ester compound (CAS No.: 29113-70-0) synthesized in this embodiment is as follows: .

[0056] Example 3: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: 45.2 mg (0.2 mmol) of (E)-3-(4-fluorophenyl)-1-phenylprop-2-en-1-one, 280 mg (0.6 mmol) of α-diazoiodonium salt and 1.72 mg (0.002 mmol) of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate) salt were added to 1 mL of N,N-dimethylformamide (analytical grade). The mixture was then irradiated with blue light at a wavelength of 456 nm and stirred at 10 °C for 1 h. The temperature was then raised to 70 °C and stirred for another 1 h. After cooling to room temperature, the solvent was removed by rotary evaporation, followed by column chromatography. The eluent for column chromatography consisted of petroleum ether and ethyl acetate in a volume ratio of 100:1, yielding 32.2 mg of 2,5-diphenylfuran-3-carboxylic acid ester compounds (yield: 52%).

[0057] The 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in this embodiment is shown below. Figure 5 As shown, the carbon NMR spectrum is as follows: Figure 6 As shown.

[0058] Spectral analysis: 1 H NMR (500 MHz, CDCl3): δ 8.14 - 8.06 (m, 2H), 7.76 - 7.69 (m, 2H), 7.42 (t, J= 7.7 Hz, 2H), 7.35 - 7.27 (m, 1H), 7.14 (t, J = 8.7 Hz, 2H), 7.07 (s,1H), 4.33 (q, J = 7.1 Hz, 2H), 1.37 (t, J = 7.1 Hz, 3H).

[0059] 13 C NMR (126 MHz, CDCl3): δ 164.27, 163.53, 162.28, 155.61, 152.32,130.51, 130.44, 129.69, 128.84, 128.16, 126.04, 126.01, 124.00, 115.59,115.34, 115.16, 107.85, 60.72, 14.29.

[0060] HR-MS: Theoretical value [M+H] + :C 19 H 15 FO3: 311.1078, Measured value: 311.1081.

[0061] In summary, the structural formula of the 2,5-diphenylfuran-3-carboxylic acid ester compound (CAS No.: 2409958-04-7) synthesized in this embodiment is as follows: .

[0062] Example 4: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: 48.4 mg (0.2 mmol) of (E)-3-(4-chlorophenyl)-1-phenylprop-2-en-1-one, 280 mg (0.6 mmol) of α-diazoiodonium salt and 1.72 mg (0.002 mmol) of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate) salt were added to 1 mL of N,N-dimethylformamide (analytical grade). The mixture was then irradiated with blue light at a wavelength of 456 nm and stirred at 10 °C for 1 h. The temperature was then raised to 70 °C and stirred for another 1 h. After cooling to room temperature, the solvent was removed by rotary evaporation, followed by column chromatography. The eluent for column chromatography consisted of petroleum ether and ethyl acetate in a volume ratio of 100:1, yielding 30.7 mg of 2,5-diphenylfuran-3-carboxylic acid esters (yield: 47%).

[0063] The 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in this embodiment is shown below. Figure 7 As shown, the carbon NMR spectrum is as follows: Figure 8 As shown.

[0064] Spectral analysis: 1 H NMR (500 MHz, CDCl3): δ 8.14 - 8.01 (m, 2H), 7.76 - 7.69 (m, 2H), 7.42 (dt, J = 7.5, 3.3 Hz, 4H), 7.32 (t, J = 7.4 Hz, 1H), 7.08 (s, 1H), 4.33 (q, J = 7.1 Hz, 2H), 1.37 (t, J = 7.1 Hz, 3H).

[0065] 13 C NMR (126 MHz, CDCl3): δ 163.43, 155.21, 152.56, 135.27, 129.59,128.86, 128.43, 128.26, 128.21, 124.05, 116.19, 108.02, 60.79, 14.30.

[0066] HR-MS: Theoretical value [M+H] + :C 19 H 15 ClO3: 327.0782, measured value: 327.0785.

[0067] In summary, the structural formula of the 2,5-diphenylfuran-3-carboxylic acid ester compound (CAS No.: 215812-61-6) synthesized in this embodiment is as follows: .

[0068] Example 5: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: 57.0 mg (0.2 mmol) of (E)-3-(4-bromophenyl)-1-phenylpropanone-2-en-1-one, 280 mg (0.6 mmol) of α-diazoiodomonium salt and 1.72 mg (0.002 mmol) of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate) salt were added to 1 mL of N,N-dimethylformamide (analytical grade). The mixture was then irradiated with blue light at a wavelength of 456 nm and stirred at 10 °C for 1 h. The temperature was then raised to 70 °C and stirred for another 1 h. After cooling to room temperature, the solvent was removed by rotary evaporation, followed by column chromatography. The eluent used in the column chromatography consisted of petroleum ether and ethyl acetate in a volume ratio of 100:1, yielding 27.4 mg of 2,5-diphenylfuran-3-carboxylic acid ester compounds (yield: 37%).

[0069] The 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in this embodiment is shown below. Figure 9 As shown, the carbon NMR spectrum is as follows: Figure 10 As shown.

[0070] Spectral analysis: 1 H NMR (400 MHz, CDCl3): δ 9.79 (s, 1H), 8.65 (dd, J = 4.9, 1.2 Hz, 1H),7.92-7.87 (m, 1H), 7.46 (d, J = 8.0 Hz, 1H), 7.34-7.31 (m, 1H), 7.27 (d, J = 8.9Hz, 1H), 7.07 (d, J = 2.4 Hz, 1H), 6.82 (dd, J = 8.9, 2.5 Hz, 1H), 6.39 (s, 1H), 3.87 (s, 3H), 3.20 (t, J = 7.5 Hz, 2H), 2.86-2.82 (m, 2H).

[0071] 13 C NMR (101 MHz, CDCl3): δ 201.4, 154.9, 151.3, 149.7, 140.0, 138.5,132.3, 129.1, 122.0, 120.6, 111.7, 111.0, 102.6, 102.3, 55.8, 42.9, 20.5.

[0072] HR-MS: Theoretical value [M+H]+ :C 19 H 16 BrO3: 371.0283, measured value: 371.0279.

[0073] In summary, the structural formula of the 2,5-diphenylfuran-3-carboxylic acid ester compound (CAS No.: 2409958-05-8) synthesized in this embodiment is as follows: .

[0074] Example 6: A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid esters includes the following steps: 55.2 mg (0.2 mmol) of (E)-1-phenyl-3-(4-(trifluoromethyl))phenyl)-2-propen-1-one, 280 mg (0.6 mmol) of α-diazoiodonium salt and 1.72 mg (0.002 mmol) of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate) salt were added to 1 mL of N,N-dimethylformamide (analytical grade). The mixture was then irradiated with blue light at a wavelength of 456 nm and stirred at 10 °C for 1 h. The temperature was then raised to 70 °C and stirred for another 1 h. After cooling to room temperature, the solvent was removed by rotary evaporation. Column chromatography was then performed using a petroleum ether and ethyl acetate eluent in a volume ratio of 100:1 to obtain 72.0 mg of 2,5-diphenylfuran-3-carboxylic acid ester compounds (yield: 37%).

[0075] The 1H NMR spectrum of the 2,5-diphenylfuran-3-carboxylic acid ester compound synthesized in this embodiment is shown below. Figure 11 As shown, the carbon NMR spectrum is as follows: Figure 12 As shown.

[0076] Spectral analysis: 1 H NMR (500 MHz, CDCl3): δ 8.22 (d, J = 8.2 Hz, 2H), 7.77 - 7.66 (m,4H), 7.43 (t, J = 7.8 Hz, 2H), 7.34 (d, J = 7.3 Hz, 1H), 7.10 (s, 1H), 4.35 (q, J = 7.1 Hz, 2H), 1.38 (t, J = 7.1 Hz, 3H).

[0077] 13C NMR (126 MHz, CDCl3): δ 163.26, 154.44, 153.21, 129.44, 128.90,128.47, 128.45, 125.12, 125.09, 124.15, 117.34, 108.16, 60.93, 14.26.

[0078] HR-MS: Theoretical value [M+H] + :C 20 H 15 O3F3: 361.1046, Measured value: 361.1060.

[0079] In summary, the structural formula of the 2,5-diphenylfuran-3-carboxylic acid ester compound (CAS No.: 2810906-56-8) synthesized in this embodiment is as follows: .

[0080] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A photocatalytic synthesis method for 2,5-diphenylfuran-3-carboxylic acid ester compounds, characterized in that, Includes the following steps: An α,β-unsaturated ketone compound, an α-diazoiodonium salt, and a catalyst were dispersed in an organic solvent, followed by a coupling cyclization reaction under light irradiation. The α,β-unsaturated ketone compound was... In the formula, R 1 Selected from methyl, methoxy, -F, -Cl, -Br or trifluoromethyl, R 2 Selected from -H, methyl, or -F, R 3 Selected from -H, methyl, -F, -Br, or methoxy, α-diazoiodomonium salts are... 2,5-Diphenylfuran-3-carboxylic acid esters were obtained.

2. The photocatalytic synthesis method according to claim 1, characterized in that: The molar ratio of the α,β-unsaturated ketone compound to the α-diazoiodonium salt is 1:2 to 4.

3. The photocatalytic synthesis method according to claim 1 or 2, characterized in that: The α-diazo iodoium salt is prepared by a method comprising the following steps: dissolving iodophenyl diacetic acid in a solvent and placing it in an ice bath, then adding trimethylsilyl trifluoromethanesulfonate, then adding ethyl diazonium in batches, then reacting at room temperature, and then separating and purifying the product.

4. The photocatalytic synthesis method according to claim 1, characterized in that: The molar ratio of the α,β-unsaturated ketone compound to the catalyst is 1:0.01 to 0.

02.

5. The photocatalytic synthesis method according to claim 1 or 4, characterized in that: The catalyst is at least one of tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate), tris(4,7-biphenyl-1,10-o-phenanthroline)ruthenium dichloride, and tris[4,4'-bis(tert-butyl)-2,2'-bipyridine]ruthenium hexafluorophosphate(II).

6. The photocatalytic synthesis method according to claim 1, characterized in that: The organic solvent is at least one of N,N-dimethylformamide, N-methylpyrrolidone, and N,N-dimethylacetamide.

7. The photocatalytic synthesis method according to claim 1, characterized in that: The coupling cyclization reaction was carried out under blue light irradiation and at a temperature of 10°C to 70°C.

8. The photocatalytic synthesis method according to claim 1 or 7, characterized in that: The coupling cyclization reaction takes 1 to 24 hours.

9. The photocatalytic synthesis method according to claim 1, characterized in that: After the coupling cyclization reaction was completed, the reaction products were subjected to column chromatography.

10. The photocatalytic synthesis method according to claim 9, characterized in that: The column chromatography uses an eluent composed of petroleum ether and ethyl acetate.

Images