Photocatalytic trifluoromethyl-alkynylation of 1,6-dienes and applications thereof

Abstract

The application discloses a trifluoromethyl alkynyl reaction containing photocatalysis 1,6-diene and application. 1,6-diene and alkynyl trifluoromethyl sulfone are used as raw materials, dimethyl benzoyl peroxide and sodium acetate additives are used, methyl tert-butyl ether is used as a reaction solvent, and a five-membered ring compound containing trifluoromethyl and alkynyl is obtained by reaction at room temperature. The synthesis method has the advantages of mild reaction condition, simple and safe operation, cheap and easily available raw material, and is an environment-friendly green synthesis method. Through the method, the trifluoromethyl alkynyl reaction of 1,6-diene can be successfully realized, and the obtained product can be used as an important organic synthon, and a series of molecular structures containing trifluoromethyl can be prepared through further oxidation or reduction reaction.

Description

Technical Field

[0001] This invention relates to the field of chemical synthesis, specifically to a trifluoromethyl alkynylation reaction containing a photocatalyst for 1,6-diene and its application. Background Technology

[0002] Fluorine-containing compounds are an important class of compounds in the field of chemistry and chemical engineering. Due to the high electronegativity, low polarizability, and small atomic radius of fluorine atoms, the introduction of fluorine atoms leads to unique physical, chemical, and biological properties in compounds. For example, in biochemistry, drug structures using trifluoromethyl as the fluorine source increase the chemical stability, metabolic stability, and electronegativity of candidate drugs, improving their lipophilicity and bioavailability. Furthermore, fluorine-containing compounds have been extensively and deeply researched and applied in numerous high-tech fields (nuclear energy, aerospace, semiconductors, etc.) and major industries (chlor-alkali industry and new energy projects, etc.). Since naturally occurring fluorine-containing organic compounds are almost non-existent in nature, artificial chemical synthesis is the primary method for obtaining them. On the other hand, the alkynyl group is an important functional group in medicinal chemistry, materials science and synthetic chemistry, and can be further transformed into various valuable functional molecules (J.Am.Chem.Soc.,2018,140,10965-10969). Therefore, developing a new method for the synthesis of trifluoromethyl alkynylation under green and mild conditions, and introducing alkynyl groups into the substrate at the same time, has important research value and significance, and will promote the further development of this research field. Summary of the Invention

[0003] This invention proposes a photocatalytic trifluoromethyl alkynylation reaction of 1,6-dienes: using 1,6-dienes and alkynyltrifluoromethyl sulfone compounds as raw materials under room temperature light irradiation, the bifunctionalization of 1,6-olefin compounds was achieved, yielding five-membered ring compounds containing trifluoromethyl and alkynyl groups. Some of these compounds exhibit certain antitumor activity. Furthermore, the synthesized five-membered ring compounds can serve as important organic synthesis intermediates, and through further oxidation or reduction reactions, a series of molecular structures containing trifluoromethyl groups can be prepared.

[0004] The technical solution for realizing the present invention is:

[0005] The photocatalytic trifluoromethyl alkynylation reaction of 1,6-diene is characterized by the following steps: A magnetic stir bar, 1,6-diene, alkynyl trifluoromethyl sulfone, benzoyl peroxide (BPO), sodium acetate, and methyl tert-butyl ether (TBME) are sequentially added to a Schlenk reaction tube. The tube is degassed by freezing, purged with nitrogen three times, sealed, and then irradiated with light at 430 nm (10 W) at room temperature for 12 hours. After the reaction is complete, saturated sodium chloride solution and dichloromethane are added for extraction, and the organic phase is collected. The crude product is purified by silica gel column chromatography to obtain a bifunctionalized product containing trifluoromethyl and alkynyl groups.

[0006] The structural formula of the prepared trifluoromethyl ynylated five-membered ring compound (III) is as follows:

[0007]

[0008] Where X is C(CO2Et)2, C(CO2Ph)2, C(CO2Bn)2, p-methylbenzamide, and butyramide; R 2 It is 4-methyl, 4-fluoro, 4-chloro, 4-bromo, 3-methyl, 3-chloro;

[0009] The 1,6-diene compound (I) has the following structural formula:

[0010]

[0011] Where X is C(CO2Et)2, C(CO2Ph)2, C(CO2Bn)2, p-methylbenzamide, and butyramide;

[0012] The structure of the alkynyl trifluoromethyl sulfone(II) is as follows:

[0013]

[0014] Among them, R 2 The compounds are 4-methyl, 4-fluoro, 4-chloro, 4-bromo, 3-methyl, and 3-chloro; prepared according to methods reported in the literature (Org. Lett., 2015, 17, 2322-2325);

[0015] The molar ratio of the 1,6-diene, alkynyl trifluoromethyl sulfone, benzoyl peroxide, and sodium acetate is 1:2:0.2:1.5.

[0016] The general reaction formula of the preparation method described in this invention is as follows:

[0017]

[0018] The beneficial effects of this invention are as follows: This invention provides a novel method for synthesizing five-membered ring compounds containing trifluoromethyl and alkynyl groups. By using BPO as an initiator under light irradiation, the trifluoromethylation and alkynylation of 1,6-dienes are achieved. The method is mild, uses inexpensive and readily available raw materials, is simple to operate, has high yield, and involves no metals. Preliminary experimental results show that the target compound can serve as an important organic synthon in organic synthesis, and a series of organic molecules containing trifluoromethyl groups can be prepared through oxidation or reduction reactions. Attached Figure Description

[0019] Figure 1 This is a graph showing the in vitro antitumor activity test results of the target product in Example 7;

[0020] Figure 2 This is a graph showing the in vitro antitumor activity test results of the target product in Example 8; Detailed Implementation

[0021] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1

[0023] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0024] A magnetic stir bar, diethyl diallyl malonate (0.2 mmol), phenylethynyl trifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at 430 nm, 10 W, and room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 65% yield.

[0025]

[0026] 1H NMR(400MHz,Chloroform-d)δ7.41–7.34(m,2H),7.32–7.24(m,3H),4.25–4.13(m ,4H),2.61–2.45(m,4H),2.44–2.20(m,5H),2.20–2.08(m,1H),1.28–1.20(m,6H). 13 C NMR (101MHz, Chloroform-d) δ172.25, 172.19, 131.5, 128.2, 127.8, 127.1 (q, J = 277.0Hz), 123.5, 87. 7,82.1,61.7,58.8,40.9,38.5,38.4,35.8(q,J=2.2Hz),33.6(q,J=28.2Hz),20.2,14.0(d,J=1.7Hz). 19 F NMR(376MHz,Chloroform-d)δ-64.44.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 26 F3O4, 411.1778, found: 411.1784.

[0027] Example 2

[0028] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0029] A magnetic stir bar, diallyl diphenyl malonate (0.2 mmol), phenylethynyl trifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at 430 nm, 10 W, and room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 41% yield.

[0030]

[0031] 1 H NMR(400MHz,Chloroform-d)δ7.45–7.31(m,6H),7.30–7.20(m,5H),7.11(dd, J=13.4,7.6Hz,4H),3.02–2.74(m,2H),2.73–2.53(m,4H),2.50–2.07(m,4H).13 C NMR(101MHz,Chloroform-d)δ170.70,170.66,150.6(d,J=2.0Hz),131.6,129.6(d,J=4.4Hz),128.3,128.0,127.0(q,J=276.8Hz) ,126.3(d,J=3.7Hz),123.4,121.1(d,J=5.2Hz),87.4,82.5,58.9,41.0,38.7,38.5,36.1(q,J=2.2Hz),33.6(q,J=28.3Hz),20.2. 19 F NMR(376MHz,Chloroform-d)δ-64.36.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 30 H 26 F3O4, 507.1778, found: 507.1779.

[0032] Example 3

[0033] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0034] A magnetic stir bar, diallyl malonate dibenzyl ester (0.2 mmol), phenylethynyltrifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at 430 nm, 10 W, and room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 63% yield.

[0035]

[0036] 1 H NMR (400MHz, Chloroform-d) δ7.46–7.37(m,2H),7.39–7.23(m,13H),5.20–5.08(m,4H),2.65–2.42(m,4H),2.41–1.95(m,6H). 13C NMR(101MHz,Chloroform-d)δ171.93,171.87,135.4(d,J=5.0Hz),131.6,128.6(d,J=4.5Hz),128.4(d,J=4.5Hz),128.3,128.1(d,J=3.7Hz ), 127.9, 127.1 (q, J = 277.2Hz), 123.5, 87.6, 82.2, 67.5 (d, J = 3.3Hz), 58.9, 40.8, 38.6, 38.5, 35.8 (q, J = 2.2Hz), 33.6 (q, J = 28.4Hz), 20.3. 19 F NMR(376MHz,Chloroform-d)δ-64.35.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 32 H 30 F3O4, 535.2091, found: 535.2092.

[0037] Example 4

[0038] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0039] A magnetic stir bar, diethyl diallyl malonate (0.2 mmol), 4-fluorophenylethynyltrifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at 430 nm, 10 W, and room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 63% yield.

[0040]

[0041] 1 H NMR (400MHz, Chloroform-d) δ7.41–7.31(m,2H),7.03–6.93(m,2H),4.24–4.15(m,4H),2.59–2.42(m,4H),2.41–1.98(m,6H),1.30–1.19(m,6H). 13CNMR(101MHz,Chloroform-d)δ172.3,172.2,162.2(d,J=248.6Hz),133.3(d,J=8.3Hz),128.4(q,J=277.0Hz),119.5(d,J= 3.5Hz), 115.5 (d, J = 22.0Hz), 87.3, 81.0, 61.7, 58.7, 40.8, 38.5, 38.4, 35.8 (q, J = 2.3Hz), 33.6 (q, J = 28.1Hz), 20.1, 14.0. 19 F NMR(376MHz,Chloroform-d)δ-64.44,-111.78.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 25 F4O4, 429.1683, found: 429.1686.

[0042] Example 5

[0043] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0044] A magnetic stir bar, diethyl diallyl malonate (0.2 mmol), 4-chlorophenylethynyltrifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at 430 nm, 10 W, and room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 64% yield.

[0045]

[0046] 1 H NMR (400MHz, Chloroform-d) δ7.35–7.30(m,2H),7.29–7.26(m,2H),4.27–4.15(m,4H),2.60–2.43(m,4H),2.40–1.89(m,6H),1.32–1.21(m,6H). 13CNMR(101MHz,Chloroform-d)δ172.2,133.8,132.7,128.6,127.0(q,J=277.1Hz),122.0,8 8.8,81.0,61.7,58.7,40.8,38.5,38.3,35.8(q,J=2.2Hz),33.6(q,J=28.3Hz),20.2,14.0. 19 F NMR(376MHz,Chloroform-d)δ-64.37.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 25 ClF3O4,445.1388,found:445.1386.

[0047] Example 6

[0048] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0049] A magnetic stir bar, diethyl diallyl malonate (0.2 mmol), 4-methylphenylethynyltrifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at 430 nm, 10 W, and room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 58% yield.

[0050]

[0051] 1 H NMR(400MHz,Chloroform-d)δ7.27(d,J=8.0Hz,2H),7.09(d,J=7.9Hz,2H),4.24–4 .14(m,4H),2.58–2.35(m,7H),2.33(s,3H),2.32–1.88(m,3H),1.29–1.19(m,6H). 13CNMR(101MHz,Chloroform-d)δ172.3,172.2,137.8,131.4,129.0,127.1(q,J=277.0Hz),120.4,86.9,8 2.1,61.7,58.7,40.9,38.5,38.3,35.8(q,J=2.3Hz),33.6(q,J=28.1Hz),21.4,20.2,14.0(d,J=1.4Hz). 19 F NMR(376MHz,Chloroform-d)δ-64.39.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 23 H 28 F3O4, 425.1934, found: 425.1935.

[0052] Example 7

[0053] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0054] A magnetic stir bar, N,N-allyl-4-methylbenzamide (0.2 mmol), phenylethynyltrifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at room temperature for 12 hours at 430 nm and 10 W. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 53% yield. This compound exhibited certain antitumor activity against Ramos tumor cells, with an IC50 value of [missing value]. 50 =8.772 μmol / L ( Figure 1 ).

[0055]

[0056] 1 H NMR(400MHz,Chloroform-d)δ7.44–7.35(m,3H),7.32–7.26(m,4H),7.17(t,J=7 .8Hz,2H),3.94–3.49(m,4H),2.82–2.38(m,5H),2.37(s,3H),2.33–2.12(m,1H). 13C NMR(101MHz,Chloroform-d)δ170.1,140.4,140.2,133.5,133.4,131.5,129.0 ,128.32,128.26,128.11,128.06,127.3,126.6(q,J=276.6Hz),123.1,123.0, 86.5,86.2,82.60,82.56,53.9,52.7,50.7,49.5,40.5,38.9,35.9(q,J=2.0Hz ),34.4(q,J=2.2Hz),32.8(q,J=29.4Hz),32.2(q,J=28.9Hz),21.4,19.4,18.5. 19 FNMR(376MHz,Chloroform-d)δ-64.65,-64.85.HRMS(ESI-TOF)m / z:[M+Na] + calcd for C 23 H 22 F3NNaO,408.1546,found:408.1548.

[0057] Example 8

[0058] The preparation method of a five-membered ring compound containing trifluoromethyl and alkynyl groups includes the following steps:

[0059] A magnetic stir bar, N,N-allyl-4-butanamide (0.2 mmol), phenylethynyltrifluoromethyl sulfone (0.4 mmol), BPO (0.04 mmol), sodium acetate (0.3 mmol), and 2 mL of methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated at room temperature for 12 hours at 430 nm and 10 W. After the reaction was complete, the mixture was extracted with saturated sodium chloride solution and dichloromethane. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to obtain the target product in 46% yield. This compound exhibited certain antitumor activity against Ramos tumor cells, with an IC50 concentration of [missing value]. 50 =4.007 μmol / L ( Figure 2 ).

[0060]

[0061] 1H NMR(400MHz,Chloroform-d)δ7.41–7.33(m,2H),7.33–7.26(m,3H),3.82–3.56(m,3H),3.48–3.28(m,1H),2.80 –2.50(m,3H),2.50–2.33(m,2H),2.29–2.15(m,3H),1.68(dt,J=14.8,7.4Hz,2H),0.95(dt,J=12.2,7.4Hz,3H). 13 CNMR(101MHz,Chloroform-d)δ172.0,171.9,131.53,131.52,128.34,128.28,128.13,128.06,126.6(q,J=277.0Hz),123.1,123.0,86.5,86.4,82.5, 82.4,51.0,50.0,48.8,40.6,38.9,36.50,36.48,35.7(q,J=2.1Hz),34.2( q, J=2.4Hz), 32.5 (qd, J=28.8, 3.1Hz), 19.2, 18.7, 18.4, 18.2, 14.0, 13.9. 19 F NMR(376MHz,Chloroform-d)δ-64.58,-64.87.HRMS(ESI-TOF)m / z:[M+Na] + calcdfor C 19 H 22 F3NNaO,360.1546,found:360.1548.

[0062] Example 9

[0063] The preparation method of compound (Ⅳ) is as follows:

[0064]

[0065] In a 25 mL round-bottom flask, the product obtained in Example 1 (0.2 mmol), AcOH (0.6 mL), and TEBAC (0.1 mmol) were dissolved in 3.0 mL of dichloromethane. Then, a solution of KMnO4 (0.6 mmol) in H2O (3.0 mL) was added to the mixture. The reaction mixture was stirred at room temperature for 8 hours, and then a small amount of Na2SO3 was added to remove excess KMnO4 and the generated MnO2. Extraction was performed with saturated sodium chloride solution and dichloromethane. The crude product obtained by rotary evaporation of the organic solvent was purified by silica gel column chromatography to give compound (Ⅳ) in 92% yield.

[0066]

[0067] 1 H NMR(400MHz,Chloroform-d)δ8.06–7.93(m,2H),7.68–7.61(m,1H),7.50(t,J=7.8Hz,2H),4. 25–4.12(m,4H),2.98–2.75(m,3H),2.64–2.46(m,3H),2.26–2.04(m,4H),1.27–1.20(m,6H). 13 C NMR(101MHz,Chloroform-d)δ201.3,191.5,172.4,172.0,134.7,131.7,130.3,128.9,126.8(q,J=277.1Hz) ,61.8(d,J=9.1Hz),58.3,38.8,38.3,37.9,36.7,36.0(q,J=2.2Hz),33.8(q,J=28.2Hz),14.0(d,J=3.6Hz). 19 F NMR(376MHz,Chloroform-d)δ-64.35.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 26 F3O6, 443.1676, found: 443.1678.

[0068] Example 10

[0069] The preparation method of compound (V) is as follows:

[0070]

[0071] In a flame-dried sealed tube, a mixture of the product obtained in Example 1 (0.1 mmol) and 10 wt% Pd / C (0.005 mmol) in ethyl acetate (1 mL) was reacted under a hydrogen atmosphere for 36 hours. After the reaction was complete, the mixture was filtered, and the crude product obtained by rotary evaporation of the organic solvent was purified by silica gel column chromatography to give compound (V) in 87% yield.

[0072]

[0073] 1H NMR(400MHz,Chloroform-d)δ7.30–7.25(m,2H),7.21–7.13(m,3H),4.20–4.13(m,4H),2.66–2.56(m,2H),2.49–2.31(m,3H) ,2.22–1.93(m,5H),1.75–1.65(m,1H),1.60–1.51(m,1H),1.37–1.27(m,1H),1.23(td,J=7.1,1.5Hz,6H),1.20–1.12(m,1H). 13 C NMR(101MHz,Chloroform-d)δ172.6,172.5,142.2,128.3(d,J=1.9Hz),127.3(q,J=277.1Hz), 125.8,61.6(q,J=1.5Hz),58.6,42.0,38.4,38.2,35.9,33.2(q,J=27.7Hz),29.7,28.5,14.0. 19 F NMR(376MHz,Chloroform-d)δ-64.25.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 30 F3O4, 415.2091, found: 415.2108.

[0074] Example 11

[0075] The preparation method of compound (VI) is as follows:

[0076]

[0077] In a flame-dried sealed tube, at 0°C, a solution of 0.2 mmol of the product obtained in Example 1 in anhydrous tetrahydrofuran (2 mL) was added dropwise to a suspension of 0.6 mmol of LiAlH4 in anhydrous tetrahydrofuran (0.5 mL) for 30 minutes. After reacting for 3 hours, the reaction was quenched with saturated NH4Cl aqueous solution (4 mL). The aqueous layer was extracted with ethyl acetate, followed by washing the organic layer with brine, drying with MgSO4, and filtering. The crude product obtained by rotary evaporation of the organic solvent was purified by silica gel column chromatography to give compound (VI) in 83% yield.

[0078]

[0079] 1H NMR(400MHz,Chloroform-d)δ7.41–7.35(m,2H),7.33–7.25(m,3H),3.63(s,2 H),3.52(s,2H),3.41(d,J=12.0Hz,2H),2.44–1.96(m,6H),1.85–1.37(m,4H). 13 C NMR(101MHz,Chloroform-d)δ131.5,128.3,127.9,127.2(q,J=277.2Hz),123.5,88.5, 82.0,70.9,69.2,47.2,40.4,36.4,36.2,35.2(q,J=2.0Hz),34.1(q,J=27.9Hz),20.8. 19 F NMR(376MHz,Chloroform-d)δ-64.25.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 18 H 22 F3O2, 327.1566, found: 327.1572.

[0080] Example 12

[0081] The preparation method of compound (VII) is as follows:

[0082]

[0083] In a flame-drying flask, phenylboronic acid (0.1 mmol) was added to a mixed solution of compound (VI) (0.1 mmol), anhydrous MgSO4 (0.2 mmol), and anhydrous tetrahydrofuran (1 mL). The reaction was stirred at room temperature for 4 hours. After the reaction was complete, the mixture was extracted with saturated sodium chloride solution and dichloromethane. The crude product obtained by rotary evaporation of the organic solvent was then purified by silica gel column chromatography to give compound (VII) in 95% yield.

[0084]

[0085] 1 H NMR(400MHz,Chloroform-d)δ7.82–7.75(m,2H),7.44–7.33(m,5H),7.33–7.25(m,3H),3.97(s,2H),3.85(s,2 H),2.50–2.33(m,5H),2.19–2.08(m,1H),1.96–1.78(m,2H),1.71(dd,J=14.3,3.9Hz,1H),1.64–1.54(m,1H).13 C NMR(101MHz,Chloroform-d)δ133.9,131.5,130.8,128.3,128.0,127.6,127.1(q,J=277.3Hz),12 3.4,87.9,82.3,72.3,70.8,42.6,40.3,37.6,37.4,35.5(q,J=2.1Hz),34.2(q,J=28.1Hz),20.9. 19 F NMR(376MHz,Chloroform-d)δ-64.34.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 24 H 25 BF3O2,413.1894,found:413.1898.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a five-membered ring compound containing trifluoromethyl and alkynyl groups, characterized by the following steps: The following steps were performed: A magnetic stir bar, 1,6-diene, alkynyltrifluoromethyl sulfone, benzoyl peroxide, sodium acetate, and methyl tert-butyl ether were sequentially added to a Schlenk reaction tube. The tube was degassed by freezing, purged with nitrogen three times, sealed, and then irradiated with light at a wavelength of 430 nm and a power of 10 W at room temperature for 12 hours. After the reaction was complete, saturated sodium chloride solution and dichloromethane were added for extraction, and the organic phase was collected. The crude product was purified by silica gel column chromatography to obtain a bifunctionalized product containing trifluoromethyl and alkynyl groups. The structural formula of the 1,6-diene compound (I) is as follows: Where X is C(CO2Et)2, C(CO2Ph)2, C(CO2Bn)2; The structure of the alkynyl trifluoromethyl sulfone compound (II) is as follows: Where R 2 It is 4-methyl, 4-fluoro, 4-chloro, 4-bromo, 3-methyl, 3-chloro; The structure of the five-membered ring compound (III) is as follows: Where X is C(CO2Et)2, C(CO2Ph)2, C(CO2Bn)2; R 2 It is 4-methyl, 4-fluoro, 4-chloro, 4-bromo, 3-methyl, 3-chloro.

2. The method for preparing a five-membered ring compound containing trifluoromethyl and alkynyl groups according to claim 1, characterized in that: The molar ratio of compound (I), alkynyl trifluoromethyl sulfone (II), dimethyl peroxide, and sodium acetate is 1:2:0.2:1.5.

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