A method for preparing a gamma-pyrone compound

Abstract

The application discloses a preparation method of a gamma-pyrone compound, which comprises the following steps: using a dibromo enone compound with a chemical structure general formula as shown in formula (I) and a non-terminal alkyne compound with a structure general formula as shown in formula (II) as raw materials, reacting under the action of a catalyst and an additive in an organic solvent at 100-120 DEG C for 10-24 hours to obtain a gamma-pyrone compound with a structure general formula as shown in formula (III). The dibromo enone compound and the non-terminal alkyne compound used in the method have the advantages of simple synthesis process operation, easy preparation, high conversion rate and wide substrate application range; the gamma-pyrone compound is successfully prepared by using the dibromo enone compound and the non-terminal alkyne compound as raw materials, and has the characteristics of simple and easy operation, low cost, green environmental protection, high atom economy and high yield. Since the gamma-pyrone compound is widely distributed in biological and pharmaceutical active molecules, the gamma-pyrone compound has wide application prospects.

Description

Technical Field

[0001] This invention belongs to the field of organic compound synthesis technology, and specifically relates to a method for preparing γ-pyranone compounds. Background Technology

[0002] Pyranones, as important unsaturated oxygen-containing six-membered heterocycles, are extremely common in natural products and have attracted much attention due to their unique chemical structures and diverse pharmacological effects. γ-Pyranones represent highly valuable building blocks, with their lactone structures endowing them with unique chemical properties and applications. γ-Pyranones are widely and diversely found in natural products. For example, compounds such as onchitriols I and II, cyercene A, and N-Acetylaureothamine all contain this characteristic structure. In addition to their medicinal value, γ-Pyranones also exhibit unique optical properties due to their fully conjugated structure. This structure endows some γ-Pyranone compounds with photosensitizing properties, opening up possibilities for the development of fluorescent probes, photochromic materials, and other fields.

[0003] Based on the diverse biological activities and material properties exhibited by pyranone skeletons, numerous researchers have dedicated themselves to developing simple and economical methods to construct the complex skeletons of γ-pyranone compounds. Currently, the main methods for constructing γ-pyranones include: (1) cyclization of 1,3,5-tricarbonyl compounds; (2) condensation of 1,3-dicarbonyl derivatives or enamine ketones; (3) [4+2] cyclization reaction of acetylenone with vinyl ether; (4) TsOH-mediated electrophilic cyclization of diynyl ketones; and (5) [3+3] cyclization of α,β-unsaturated alkynyl carboxylic acids with 1,3-dicarbonyl compounds as reaction substrates under the co-mediation of 4-(dimethylamino)pyridine / Lewis acid. In addition, metal-catalyzed cyclization is also an efficient method for synthesizing γ-pyranone derivatives, involving metal catalysts such as rhodium, scandium, gold, palladium, and copper. However, these methods still have certain limitations because the main precursors (raw materials) usually need to be prepared through multi-step synthesis, which not only reduces atom economy but also significantly affects the yield of the final product. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide a method for preparing γ-pyranone compounds. This method is characterized by its simple and easy-to-operate steps, environmental friendliness, low cost, high atom economy, and high yield.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The present invention provides a method for preparing γ-pyranone compounds, comprising the following steps: using dibromoenones and non-terminated alkynes with general chemical structural formulas as shown in (I) and (II) as raw materials, reacting them in an organic solvent at 100-120°C for 10-24 h under the action of a catalyst and additives to obtain γ-pyranone compounds with general structural formulas as shown in (III);

[0007]

[0008] Among them, R 1 Selected from any one of H, C1-C3 alkyl, halogen, C1-C4 alkoxy, C1-C3 ester, aromatic, and heterocyclic groups, R 2 and R 3 The same or different, selected from any one of C1-C3 alkyl, phenyl, aromatic group having C1-C3 alkyl substituents, aromatic group having halogen substituents, and heterocyclic group.

[0009] Preferably, the molar ratio of the catalyst to the dibromoenone compound is 0.01 to 0.05:1.

[0010] Preferably, the molar ratio of the additive to the dibromoenone compound is 0.01 to 0.05:1.

[0011] Preferably, the molar ratio of the non-terminated alkyne compound to the dibromoenone compound is 1.0 to 1.5:1.0.

[0012] Preferably, the dibromoenone compound is selected from any one of 3,3-dibromo-1-phenylprop-2-en-1-one, 3,3-dibromo-1-(p-tolyl)prop-2-en-1-one, 3,3-dibromo-1-(m-tolyl)prop-2-en-1-one, 3,3-dibromo-1-(4-fluorophenyl)prop-2-en-1-one, 3,3-dibromo-1-(4-methoxyphenyl)prop-2-en-1-one, methyl 4-(3,3-dibromoacryloyl)benzoate, 1-([1,1'-biphenyl]-4-yl)-3,3-dibromopropyl-2-en-1-one, and 3,3-dibromo-1-(thiophen-2-yl)prop-2-en-1-one.

[0013] Preferably, the non-terminal alkyne compound is selected from any one of diphenylacetylene, 2-butyne, 1,2-di-m-tolueneacetylene, 1,2-bis(4-fluorophenyl)acetylene, 1,2-bis(thiophen-2-yl)acetylene, and prop-1-yne-1-ylbenzene.

[0014] Preferably, the catalyst is any one of dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer, tri(triphenylphosphine)carbonyl dihydroruthenium(II), ruthenium trichloride, and dichloro(p-methylisopropylbenzene)ruthenium(II) dimer.

[0015] Preferably, the additive is any one of copper acetate, copper chloride, cuprous bromide, copper trifluoroacetate, and potassium persulfate.

[0016] Preferably, the organic solvent is any one of methanol, ethanol, acetonitrile, and ethylene glycol.

[0017] Preferably, the process further includes the step of purifying the reaction product by thin-layer chromatography after the reaction is completed, wherein the developing solvent system is petroleum ether / ethyl acetate, and the volume ratio of petroleum ether to ethyl acetate is 8 to 3:1.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The method of this invention utilizes dibromoenone compounds and non-terminated alkynes as raw materials, and its synthesis process is simple, easy to prepare, has high conversion rates, and a wide range of applicable substrates. The method features mild reaction conditions, simple and easy-to-operate steps, low cost (the catalyst used is inexpensive), few reaction byproducts, environmental friendliness, high atom economy, and high yield. Since γ-pyranone compounds are widely distributed in biologically and pharmaceutically active molecules (e.g., inhibitors, antitumor drugs), they have broad application prospects. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A synthetic route diagram for a γ-pyranone compound provided by the present invention;

[0022] Figure 2 The structural formula is a representative example of a dibromoenone compound;

[0023] Figure 3 The structural formula is a representative example of a non-terminated alkyne compound;

[0024] Figure 4 The structural formula is a representative example of a γ-pyranone compound;

[0025] Figure 5 The NMR spectrum of compound 3a-1 prepared in Example 1;

[0026] Figure 6 The carbon spectrum of compound 3a-1 prepared in Example 1 is shown. Detailed Implementation

[0027] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention may be implemented in other embodiments without these specific details.

[0028] Example 1

[0029] Reference Figure 1-4 Compound 3a-1 was prepared according to the synthetic route of γ-pyranone compounds.

[0030] Add 3,3-dibromo-1-phenylprop-2-en-1-one (compound 1-1, chemical structure shown in [reference]) sequentially to a 10 mL Shrek tube. Figure 2 0.1 mmol, 0.0289 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (5 mol%, 0.0003 g), copper acetate (0.03 mmol, 0.0005 g), and diphenylacetylene (compound 2-1, chemical structure shown in [reference]) were added. Figure 3 0.15 mmol (0.0267 g) and methanol (2.0 mL) were added and stirred at 120 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (developing solvent system: petroleum ether / ethyl acetate, volume ratio 5:1). The product was a white solid, namely compound 3a-1, with a yield of 78%. Its NMR and CMR results are shown below. Figure 5 and Figure 6 .

[0031] 1 H NMR (400MHz, CDCl3) δ7.85-7.78 (m, 2H), 7.48 (d, J = 5.1Hz, 3H), 7.31 (dd, J = 11. 2,7.5Hz,3H),7.24(dt,J=10.3,4.8Hz,5H),7.18(d,J=7.5Hz,2H),6.95(s,1H). 13 CNMR(101MHz,CDCl3)δ179.10,162.81,161.14,132.76,132.25,131.39,1 30.88,130.05,129.38,129.14,128.39,128.25,127.91,125.90,110.90.

[0032] Example 2

[0033] Add 3,3-dibromo-1-(p-tolyl)prop-2-en-1-one (compounds 1-2, chemical structural formulas shown) sequentially to a 10 mL Shrek tube. Figure 2 0.1 mmol (0.0304 g), cuprous bromide (0.03 mmol, 0.0010 g), tris(triphenylphosphine)carbonyl dihydroruthenium(II) (5 mol%, 0.0003 g), and prop-1-yn-1-ylbenzene (compounds 2-5, chemical structures shown in [reference]). Figure 3 The product was prepared by stirring at 100 °C for 10 h with 0.12 mmol (0.0139 g) and acetonitrile (1.0 mL). After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 5:1). The product was a white solid, namely compound 3a-2, with a yield of 61%.

[0034] 1 H NMR (400MHz, CDCl3) δ7.81(dd,J=7.2,2.0Hz,2H),7.65(dd,J=6.4,2.9Hz,2H),7.58-7.46(m,6H),6.87(s,1H),3.86(s,3H).2.14(s,3H). 13 C NMR (101MHz, CDCl3) δ180.73,162.82,160.70,132.86,131.52,131.22,130.21,130.12,129. 04,128.91,128.58,128.47,125.80,125.81,125.73,121.92,110.82,109.34,29.73,21.53.

[0035] Example 3

[0036] Add 3,3-dibromo-1-(m-tolyl)prop-2-en-1-one (compounds 1-3, chemical structures shown in [reference]) sequentially to a 10 mL Shrek tube. Figure 2 0.1 mmol (0.0304 g), ruthenium trichloride (5 mol%, 0.0001 g), copper chloride (0.01 mmol, 0.0002 g), and 1,2-di-m-tolueneacetylene (compound 2-2, chemical structure shown) were added. Figure 3 The product was prepared by stirring at 120 °C for 24 h with 0.15 mmol (0.031 g) and ethylene glycol (1.0 mL). After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 3:1). The product was a white solid, namely compound 3a-3, with a yield of 52%.

[0037] 1H NMR (400MHz, CDCl3) δ7.87 (dd, J=6.5, 3.1Hz, 2H), 7.52 (dd, J=5.1, 1.8Hz, 3H), 7.20 (d, J=8.0Hz, 2H), 7.1 6(d,J=8.9Hz,3H),7.10(d,J=11.5Hz,2H),6.97(d,J=6.7Hz,2H),2.44(s,3H),2.31(s,3H),2.28(s,3H). 13 C NMR (101MHz, CDCl3) δ179.25,162.67,137.87,137.84,132.67,132.23,131.48,131.36,131.32,130.76, 129.83,129.13,128.68,128.26,128.01,127.81,126.69,126.60,125.90,110.87,21.58,21.51,21.46.

[0038] Example 4

[0039] Add 3,3-dibromo-1-(4-fluorophenyl)prop-2-en-1-one (compounds 1-4, chemical structural formulas see below) sequentially to a 10 mL Shrek tube. Figure 2 The following were added: 0.1 mmol (0.0031 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (5 mol%, 0.0003 g), copper acetate (0.05 mmol, 0.0009 g), diphenylacetylene (compound 2-1, 0.15 mmol, 0.0267 g) and ethanol (1.0 mL). The mixture was stirred at 120 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (petroleum ether / ethyl acetate as the developing solvent, with a volume ratio of 8:1). The product was a white solid, namely compound 3a-4, with a yield of 71%.

[0040] 1 H NMR (400MHz, CDCl3) δ7.86 (dd, J=8.7, 5.2Hz, 2H), 7.38-7.33 (m, 3H), 7.30 (t, J=5.9Hz, 5H), 7.24-7.18 (m, 4H), 6.93 (s, 1H). 13C NMR(101MHz, CDCl3)δ178.90,161.83(d,J=2.9Hz),161.08,132.65,132.08,130.91,130.83(2C),130.09,129.33(2C), 128.39(2C),128.27(2C),128.11,128.02,127.94,127.62(d,J=3.2Hz),126.56(d,J=2.1Hz),116.50,116.28,110.67. 19 F NMR(376MHz,Chloroform-d)δ-107.826.

[0041] Example 5

[0042] Add 3,3-dibromo-1-(4-methoxyphenyl)prop-2-en-1-one (compounds 1-5, chemical structures shown in [reference]) sequentially to a 10 mL Shrek tube. Figure 2 The following were added: tris(triphenylphosphine)carbonyl dihydroruthenium(II) (5 mol%, 0.0003 g), copper acetate (0.05 mmol, 0.0009 g), diphenylacetylene (compound 2-1, 0.12 mmol, 0.0214 g) and methanol (1.0 mL). The mixture was stirred at 110 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 3:1). The product was a white solid, namely compound 3a-5, with a yield of 66%.

[0043] 1 H NMR(400MHz, CDCl3)δ7.81(d,J=8.9Hz,2H),7.39-7.34(m,3H),7.30(q,J=6.6,6.1H z,5H),7.21(dd,J=7.5,1.8Hz,2H),7.02(d,J=8.9Hz,2H),6.90(s,1H),3.89(s,3H). 13 C NMR (101MHz, CDCl3) δ179.13,162.86,162.17,160.84,132.87,132.36,130.90(2C),129. 95,129.37,128.37,128.21,127.84,127.57(2C),126.25,123.70,114.54,109.44,55.53.

[0044] Example 6

[0045] Add methyl 4-(3,3-dibromoacryloyl)benzoate (compounds 1-6, chemical structures shown in [reference]) sequentially to a 10 mL Shrek tube. Figure 2 The following were added: 0.1 mmol (0.035 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (2 mol%, 0.0001 g), copper acetate (0.05 mmol, 0.0009 g), diphenylacetylene (compound 2-1, 0.15 mmol, 0.0267 g) and methanol (1.0 mL). The mixture was stirred at 120 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (petroleum ether / ethyl acetate as the developing solvent, with a volume ratio of 5:1). The product was a white solid, namely compound 3a-6, with a yield of 56%.

[0046] 1 H NMR(400MHz, CDCl3)δ8.18(d,J=8.5Hz,2H),7.93(d,J=8.5Hz,2H),7.40-7.34(m, 3H),7.31(d,J=4.7Hz,5H),7.22(dd,J=7.4,2.0Hz,2H),7.05(s,1H),3.97(s,3H). 13 CNMR (101MHz, CDCl3) δ180.93,178.85,166.20,161.49,138.01,132.55,132.50,130. 82,130.31,130.21,128.44,128.33,128.03,125.82,124.68,124.48,112.11,52.52.

[0047] Example 7

[0048] Add 1-([1,1'-biphenyl]-4-yl)-3,3-dibromopropyl-2-en-1-one (compounds 1-7, chemical structures shown in [reference]) sequentially to a 10 mL Shrek tube. Figure 2 The following were added: 0.1 mmol (0.036 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (5 mol%, 0.0003 g), copper acetate (0.05 mmol, 0.0009 g), diphenylacetylene (compound 2-1, 0.10 mmol, 0.0178 g), and methanol (1.0 mL). The mixture was stirred at 120 °C for 20 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (petroleum ether / ethyl acetate as the developing solvent, with a volume ratio of 3:1). The product was a white solid, namely compound 3a-7, with a yield of 59%.

[0049] 1H NMR (400MHz, CDCl3) δ7.94 (d, J = 7.8Hz, 2H), 7.75 (d, J = 7.7Hz, 2H), 7.66 (d, J = 8.1Hz, 2H), 7.50 (t, J = 7. 6Hz,2H),7.40(dt,J=13.7,7.4Hz,4H),7.36-7.28(m,5H),7.24(d,J=7.7Hz,2H),7.03(d,J=1.2Hz,1H). 13 C NMR (101MHz, CDCl3) δ179.05,162.55,161.07,144.16,144.06,139.86,139.77,132.77,132.20,130.87(2C),130.11, 130.06,129.39(2C),129.03(2C),128.40,128.26,128.20,127.92,127.75,127.15(2C),126.59,126.36(2C),110.55.

[0050] Example 8

[0051] Add 3,3-dibromo-1-(thien-2-yl)prop-2-en-1-one (compounds 1-8, chemical structural formulas see below) sequentially to a 10 mL Shrek tube. Figure 2 The following were added: 0.1 mmol (0.029 g), ruthenium trichloride (5 mol%, 0.0001 g), copper acetate (0.05 mmol, 0.0009 g), diphenylacetylene (compound 2-1, 0.12 mmol, 0.0214 g) and acetonitrile (1.0 mL). The mixture was stirred at 110 °C for 20 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 3:1). The product was a brownish-yellow solid, namely compound 3a-8, with a yield of 23%.

[0052] 1 H NMR (400MHz, CDCl3) δ7.64(dd,J=3.7,1.2Hz,1H),7.55(dd,J=5.0,1.2Hz,1H),7.36(d,J=2.1Hz,1H),7.35-7.33(m,2H),7.31(d,J=1.6H z,1H),7.30(d,J=2.0Hz,2H),7.29(d,J=1.1Hz,1H),7.27(t,J=1.4Hz,1H),7.24-7.20(m,2H),7.18(dd,J=5.0,3.7Hz,1H),6.83(s,1H). 13C NMR (101MHz, CDCl3) δ178.62,158.62,134.70,132.47,132.13,130.82(2C),130.10,129 .72,129.50,129.35(2C),128.49,128.41,128.22(2C),127.95,127.80,126.48,109.40.

[0053] Example 9

[0054] 3,3-Dibromo-1-phenylprop-2-en-1-one (compound 1-1, 0.1 mmol, 0.029 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (5 mol%, 0.0003 g), copper trifluoroacetate (0.03 mmol, 0.0009 g), 1,2-bis(thiophene-2-yl)acetylene (compound 2-4, 0.12 mmol, 0.0228 g), and methanol (1.0 mL) were added sequentially to a 10 mL Shrek tube. The mixture was stirred at 120 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 3:1). The product was a brown solid, namely compound 3a-9, with a yield of 54%.

[0055] 1 H NMR (400MHz, CDCl3) δ7.91-7.86(m,2H),7.58-7.52(m,4H),7.47(dd,J=5.0,1.2Hz,1H),7.17(dd,J=5 .2,3.5Hz,1H),7.08(d,J=1.2Hz,1H),7.07(d,J=1.2Hz,1H),7.02(dd,J=5.0,3.8Hz,1H),6.90(s,1H). 13 C NMR (101MHz, CDCl3) δ178.76,162.39,156.97,134.20,132.01,131.54,131.14,131 .07,130.88,129.64,129.22,128.49,127.82,127.57,125.92(2C),117.97,110.09.

[0056] Example 10

[0057] 3,3-Dibromo-1-phenylprop-2-en-1-one (compound 1-1, 0.1 mmol, 0.029 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (5 mol%, 0.0003 g), copper acetate (0.05 mmol, 0.0009 g), 2-butyne (compound 2-6, 0.15 mmol, 0.0008 g), and methanol (1.0 mL) were added sequentially to a 10 mL Shrek tube. The mixture was stirred at 120 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 6:1). The product was a white solid, namely compound 3a-10, with a yield of 8%.

[0058] 1 H NMR (400MHz, CDCl3) δ7.76 (dd, J = 6.4, 2.9Hz, 2H), 7.54-7.43 (m, 3H), 6.73 (s, 1H), 2.41 (s, 3H), 2.00 (s, 3H). 13 C NMR (101MHz, CDCl3) δ180.02,162.44,161.14,131.05,131.04,128.99(2C),125.64(2C),109.47,29.73,17.83.

[0059] Example 11

[0060] 3,3-Dibromo-1-phenylprop-2-en-1-one (compound 1-1, 0.1 mmol, 0.029 g), dichloro(p-methylisopropylbenzene)ruthenium(II) dimer (5 mol%, 0.0003 g), copper acetate (0.05 mmol, 0.0009 g), prop-1-yn-1-ylbenzene (compound 2-5, 0.15 mmol, 0.0174 g), and methanol (1.0 mL) were added sequentially to a 10 mL Shrek tube. The mixture was stirred at 120 °C for 24 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 3:1). The product was a white solid, namely compound 3a-11, with a yield of 81%.

[0061] 1 H NMR (400MHz, CDCl3) δ7.81 (dd, J=7.2, 2.0Hz, 2H), 7.65 (dd, J=6.4, 2.9Hz, 2H), 7.58-7.46 (m, 6H), 6.87 (s, 1H), 2.14 (s, 3H). 13C NMR (101MHz, CDCl3) δ180.73,162.82,160.70,132.86,131.52,131.22,130.21,130.12,129. 04,128.91,128.58,128.47,125.80,125.81,125.73,121.92,110.82,109.34,29.73,11.53.

[0062] Example 12

[0063] 3,3-Dibromo-1-phenylprop-2-en-1-one (compound 1-1, 0.1 mmol, 0.029 g), dichloro(pentamethylcyclopentadienyl)ruthenium(III) polymer (5 mol%, 0.0003 g), copper acetate (0.05 mmol, 0.0009 g), 1,2-bis(4-fluorophenyl)acetylene (compound 2-3, 0.12 mmol, 0.031 g), and ethanol (1.0 mL) were added sequentially to a 10 mL Shrek tube. The mixture was stirred at 120 °C for 20 h. After the reaction was completed by TLC monitoring, the product was separated and purified by thin-layer chromatography (the developing solvent system was petroleum ether / ethyl acetate, with a volume ratio of 8:1). The product was a white solid, namely compound 3a-12, with a yield of 65%.

[0064] 1 H NMR (400MHz, CDCl3) δ7.84(dd,J=7.5,1.9Hz,2H),7.57-7.49(m,3H),7.40-7.33(m,2H),7.19(dd,J=8.6,5.5Hz,2H),7.07-6.95(m,5H). 13 C NMR (101MHz, CDCl3) δ178.80,178.80,164.73,163.69,162.97(dd,J=250.0,101.8Hz),161.23,160.24,132.61(d,J=8.1 Hz),131.54,131.52,131.43,131.12,129.03(2C)129.20,128.66(d,J=3.4Hz),125.89,125.89,115.78,115.57,110.83. 19 F NMR(376MHz,Chloroform-d)δ-108.86,-113.50.

[0065] This invention is not limited to the specific embodiments described above. Any modifications made by those skilled in the art based on the above concept without creative effort are within the scope of protection of this invention.

Claims

1. A gamma- Process for the preparation of pyrones, characterized in that, The method comprises the following steps: using dibromo enone and non-terminal alkyne compounds with chemical structure general formula as shown in (I) and (II) as raw materials, reacting at 100-120 DEG C for 10-24 hours in an organic solvent under the action of a catalyst and an additive to obtain pyrone compounds with general formula as shown in (III) gamma- Pyrones: wherein R is selected from the group consisting of H, C1-C3 alkyl, halogen, C1-C4 alkoxy, C1-C3 ester, aryl, heterocyclyl, R 1 and R 2 are the same or different and are selected from the group consisting of H, C1-C3 alkyl, phenyl, aryl substituted with C1-C3 alkyl, aryl substituted with halogen, heterocyclyl; and R 3 is selected from the group consisting of H, C1-C3 alkyl, halogen, C1-C4 alkoxy, C1-C3 ester, aryl, heterocyclyl. The catalyst is any one of dichloro (pentamethylcyclopentadienyl) ruthenium (III) polymer, tris (triphenylphosphine) carbonyl dihydrogen ruthenium (II), ruthenium trichloride, dichloro (p-methylisopropylbenzene) ruthenium (II) dimer; The additive is any one of copper acetate, copper chloride, cuprous bromide, copper trifluoroacetate, potassium persulfate; The molar ratio of the catalyst to the dibromo enone compound is 0.01-0.05:1; The molar ratio of the additive to the dibromo enone compound is 0.01-0.05:1; The molar ratio of the non-terminal alkyne compound to the dibromo enone compound is 1.0-1.5:1.

0.

2. The method of claim 1, gamma- A method for producing a pyrone compound, characterized by, The dibromo enone compound is any one of 3,3-dibromo-1-phenylprop-2-en-1-one, 3,3-dibromo-1- (p-tolyl) prop-2-en-1-one, 3,3-dibromo-1- (m-tolyl) prop-2-en-1-one, 3,3-dibromo-1- (4-fluorophenyl) prop-2-en-1-one, 3,3-dibromo-1- (4-methoxyphenyl) prop-2-en-1-one, 4- (3,3-dibromoacryloyl) benzoic acid methyl ester, 1- ( [1,1'-biphenyl] -4-yl) -3,3-dibromoprop-2-en-1-one, 3,3-dibromo-1- (thiophene-2-yl) prop-2-en-1-one.

3. The method of claim 1, gamma- A method for producing a pyrone compound, characterized by, The non-terminal alkyne compound is any one of diphenylacetylene, 2-butyne, 1,2-di-m-tolylacetylene, 1,2-bis (4-fluorophenyl) acetylene, 1,2-di (thiophene-2-yl) acetylene, prop-1-yn-1-ylbenzene.

4. The method of claim 1, gamma- Process for the preparation of pyrones, characterized in that, The organic solvent is any one of methanol, ethanol, acetonitrile, ethylene glycol.

5. The method of claim 1, gamma- A method for producing a pyrone compound, characterized by, Further comprising the step of purifying the reaction product by thin layer chromatography after the reaction is completed, and the developing agent system used is petroleum ether / ethyl acetate, and the volume ratio of petroleum ether and ethyl acetate is 8-3:1.

Images