Synthesis method of 1, 2-allene ketone

Abstract

The invention relates to a method for synthesizing 1, 2-allene ketone, and discloses a method for synthesizing 1, 2-allene ketone by taking eneyne, 1, 4-dihydropyridine and benzoyl fluoride as substrates, 2, 4, 5, 6-tetra (diphenylamino)-isophthalonitrile as a photocatalyst, 5, 6, 7, 8-tetrahydro-3-(2, 6-diisopropyl phenyl)-4H-cycloheptyl thiazole perchlorate as N-heterocyclic carbene, cesium carbonate as alkali and acetonitrile as a solvent through a one-pot method. And reacting at room temperature for 4 hours under visible light of 12W and 460nm LED blue light to obtain allene ketone. The reaction conditions are mild, and the method has good functional group tolerance.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis, and specifically relates to a method for synthesizing a 1,2-alkenyl ketone compound. Background Art

[0002] Polysubstituted allenes and their derivatives are present in many active pharmaceutical ingredients, fine chemicals, agrochemicals, polymers, emulsifiers and plasticizers, and other chemicals. Among them, 1,2-alkenyl ketones are synthetic precursors for many active molecules and are also commonly used synthons for the synthesis of heterocyclic compounds such as furans and pyrans. Due to the challenge and practicality of its synthesis, the development of new and efficient synthetic methods has long been a hot topic for synthetic chemists. Previous methods for the synthesis of 1,2-alkenyl ketones include: oxidation reaction of allenols, Grignard reaction of allenyl esters, coupling reaction of alkynyl ketones, etc., but there are few reports on the synthesis of allenones using mild green visible light catalysis. Based on this, the development of efficient visible light catalytic 1,2-alkenyl ketone synthesis methods is of great significance in drug discovery and organic synthesis. Summary of the invention

[0003] The purpose of the present invention is to improve the deficiencies of existing preparation and synthesis methods and to provide a method for synthesizing 1,2-alkenyl ketone compounds with simple reaction conditions and a wide range of substrate applicability.

[0004] The technical scheme of the present invention is: a substrate, a photocatalyst, a nitrogen heterocyclic carbene NHC-1, and a base are placed in a test tube, a solvent is added, and a 1,2-allene-1-one compound is obtained under the conditions of argon protection, room temperature and visible light excitation. The reaction formula is as follows:

[0005]

[0006] (1)R 1 Selected from phenyl, pyridyl, methyl benzoate;

[0007] (2)R 2 is selected from n-pentyl;

[0008] (3)R 3 is selected from isopropyl, isobutyl, cyclopentyl, cyclohexyl, oxacyclopentyl, 1-methylbenzyl, 1-ethylpentyl;

[0009] (4)R 4 is selected from methyl, methoxy, phenyl, chloro, bromo;

[0010] (5) The photocatalyst used is selected from 2,4,5,6-tetrakis(diphenylamino)-isophthalonitrile;

[0011] (6) The nitrogen heterocyclic carbene used is selected from 5,6,7,8-tetrahydro-3-(2,6-diisopropylphenyl)-4H-cycloheptanthiazole perchlorate;

[0012] (7) The base used is selected from cesium carbonate;

[0013] (8) The solvent used is selected from acetonitrile;

[0014] (9) The temperature used is selected from 25°C and maintained for 4 hours;

[0015] (10) The visible light used is selected from 12W 460 nm LED blue light, and the duration is 4 hours;

[0016] (11) The molar mass ratio of each substance in the reaction is selected from: ene yne: 1,4-dihydropyridine: benzoyl fluoride: photocatalyst: nitrogen heterocyclic carbene: base = 1:2:3.5:0.02:0.2:1. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] 1. Figure 1 The synthesis conditions of 1,2-alkenyl ketone;

[0018] 2. Figure 2 is the preparation reaction formula of compound 4aa;

[0019] 3. Figure 3 is the preparation reaction formula of compound 4ab;

[0020] 4. Figure 4 is the preparation reaction formula of compound 4ac;

[0021] 5. Figure 5 is the preparation reaction formula of compound 4ba;

[0022] 6. Figure 6 is the preparation reaction formula of compound 4bb;

[0023] 7. Figure 7 is the preparation reaction formula of compound 4bc;

[0024] 8. Figure 8 is the preparation reaction formula of compound 4bd;

[0025] 9. Fig. 9 is the preparation reaction formula of compound 4be;

[0026] 10. Fig.10 is the reaction formula for the preparation of compound 4ca;

[0027] 11. Fig.11 is the preparation reaction formula of compound 4cb;

[0028] 12. Fig.12is the reaction formula for the preparation of compound 4cc;

[0029] 13. Fig.13 is the preparation reaction formula of compound 4cd;

[0030] 14. Fig.14 is the preparation reaction formula of compound 4ce;

[0031] 15. Fig.15 is the preparation reaction formula of compound 4da;

[0032] 16. Fig.16 This is the reaction formula for the preparation of compound 4db. DETAILED DESCRIPTION

[0033] The present invention is further described below through specific embodiments, but this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies implemented based on the above content of the present invention belong to the scope of the present invention.

[0034] Implementation Case 1

[0035] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3a) as raw materials (reaction formula 1)

[0036]

[0037] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4aa was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0038] The product detection data are as follows: solid, yield 79%.

[0039] 1 H NMR (400 MHz, CDCl 3)δ8.02(d,J=8.4Hz,2H),7.60(d,J=8.0Hz,2H),7.42–7.36(m,3H),7.24–7.20(m,2H),3.93(s,3H),2.62–2.49(m,2H),2 .40–2.21(m,2H),1.76–1.69(m,1H),1.64–1.56(m,2H),1.44–1.32(m,4H),0.89(t,J=7.2Hz,3H),0.82(d,J=6.4Hz,6H).

[0040] 13 C NMR (100 MHz, CDCl 3 )δ214.5,194.9,166.8,140.4,138.7,131.9,129.9,129.0,128.4,127.8,126 .4,109.7,108.2,52.1,39.9,31.8,28.9,28.1,27.0,22.6,22.5,22.3,14.0.

[0041] Implementation Case 2

[0042] Using enyne substrate (1b), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3a) as raw materials (Reaction Formula 2)

[0043]

[0044] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1b (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4ab was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0045] The product detection data are as follows: solid, yield 66%.

[0046] 1 H NMR (400 MHz, CDCl 3)δ7.55(d,J=8.0Hz,2H),7.33–7.22(m,5H),7.20–7.12(m,3H),2.50–2.42(m,2H),2.31–2.11(m,2H),1.71–1.61( m,1H),1.56–1.49(m,2H),1.36–1.25(m,4H),0.82(t,J=7.2Hz,3H),0.75(d,J=4.0Hz,3H),0.74(d,J=4.0Hz,3H).

[0047] 13 C NMR (100 MHz, CDCl 3 )δ214.2,195.4,138.9,135.4,131.7,128.6,128.5,127.7,127.4,126 .5,109.2,108.5,40.1,31.8,28.9,28.2,26.9,22.7,22.5,22.3,14.0.

[0048] Implementation Case 3

[0049] Using enyne substrate (1c), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3a) as raw materials (Reaction formula 3)

[0050]

[0051] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1c (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4ac was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 30:1).

[0052] The product detection data are as follows: solid, yield 55%.

[0053] 1 H NMR (400 MHz, CDCl 3)δ8.52–8.43(m,2H),7.54–7.49(m,3H),7.36–7.32(m,1H),7.23–7.15(m,3H),2.52–2.40(m,2H),2.32–2.14(m,2H),1.6 8–1.62(m,1H),1.55–1.48(m,2H),1.34–1.26(m,4H),0.82(t,J=6.8Hz,3H),0.70(d,J=4.0Hz,3H),0.75(d,J=3.6Hz,3H).

[0054] 13 C NMR (100 MHz, CDCl 3 )δ213.4,194.9,148.4,147.9,138.7,133.5,132.0,128.4,127.8,109.8,105.8,39.8,31.7,28.8,28.1,26.8,22.6,22.4,22.2,14.0.

[0055] Implementation Case 4

[0056] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2b), and benzoyl fluoride (3a) as raw materials (reaction formula 4)

[0057]

[0058] Under argon atmosphere, 1,4-dihydropyridine substrate 2b (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4ba was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0059] The product detection data are as follows: solid, yield 80%.

[0060] 1 H NMR (400 MHz, CDCl 3)δ8.03(d,J=8.4Hz,2H),7.60(d,J=8.0Hz,2H),7.41–7.37(m,3H),7.23–7.19(m,2H),3.93(s,3H),2.63–2.51(m,2H), 2.49–2.37(m,2H),1.95–1.88(m,1H),1.62–1.52(m,6H),1.45–1.32(m,6H),1.09–1.00(m,2H),0.89(t,J=7.2Hz,3H).

[0061] 13 C NMR (100 MHz, CDCl 3 )δ214.7,195.0,166.8,140.4,138.7,131.9,129.9,128.9,128.4,127.8,126.3,11 0.0,108.8,52.2,38.2,37.0,32.7,32.5,31.8,28.9,28.0,25.2,25.1,22.5,14.0.

[0062] Implementation Case 5

[0063] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2c), and benzoyl fluoride (3a) as raw materials (Reaction Formula 5)

[0064]

[0065] Under argon atmosphere, 1,4-dihydropyridine substrate 2c (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4bb was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0066] The product detection data are as follows: solid, yield 75%.

[0067] 1 H NMR (400 MHz, CDCl 3)δ8.02(d,J=8.4H,2H),7.59(d,J=8.4Hz,2H),7.41–7.37(m,2H),7.23–7.19(m,3H),3.92(s,3H),2.57–2.52(m,2H),2.37–2.2 2(m,2H),1.60–1.54(m,6H),1.50–1.46(m,1H),1.42–1.32(m,5H),1.07–1.03(m,3H),0.89(t,J=7.2Hz,3H),0.85–0.79(m,2H).

[0068] 13 C NMR (100 MHz, CDCl 3 )δ214.8,195.0,166.8,140.4,138.8,131.9,129.9,128.9,128.3,127.8,126.3,109.7 ,107.6,52.1,38.3,36.5,33.3,33.1,31.7,28.8,28.1,26.2,26.09,26.06,22.5,14.0.

[0069] Implementation Case 6

[0070] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2d), and benzoyl fluoride (3a) as raw materials (Reaction formula 6)

[0071]

[0072] Under argon atmosphere, 1,4-dihydropyridine substrate 2d (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4bc was purified and separated by column chromatography (eluent: petroleum ether: ethyl acetate = 40:1).

[0073] The product detection data are as follows: solid, yield 72%, dr = 1.2:1.

[0074] 1 H NMR (400 MHz, CDCl3 )δ8.04–8.01(m,2H),7.62–7.58(m,2H),7.41–7.37(m,3H),7.24–7.19(m,2H),3.92(s,3H),2.58–2.36(m,3H),2 .28–2.16(m,1H),1.62–1.56(m,2H),1.51–1.24(m,6H),1.12–1.04(m,1H),0.91–0.87(m,3H),0.81–0.75(m,6H).

[0075] 13 C NMR (100 MHz, CDCl 3 )δ214.6,214.5,194.94,194.89,166.7,140.5,140.3,138.8,138.7,131.9 ,129.90,129.88,128.92,128.89,128.4,128.3,127.81,127.78,126.4,12 6.3,109.9,109.5,108.1,108.0,52.1,37.9,37.8,33.3,33.2,31.74,31.72,29.5,29.0,28.85,28.82,28.1,28.0,22.4,19.2,19.0,14.0,11.4,11.2.

[0076] Implementation Case 7

[0077] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2e), and benzoyl fluoride (3a) as raw materials (Reaction formula 7)

[0078]

[0079] Under argon atmosphere, 1,4-dihydropyridine substrate 2e (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw material disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4bd was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0080] The product detection data are as follows: solid, yield 61%, dr = 1.2:1.

[0081] 1 H NMR (400 MHz, CDCl 3 )δ8.03(d,J=8.4Hz,2H),7.60(d,J=8.0Hz,2H),7.41–7.38(m,3H),7.23–7.19(m,2H),3.92(s,3H),2.62–2.48(m,2H),2.42–2.24 (m,2H),1.61–1.57(m,2H),1.42–1.36(m,5H),1.22–1.14(m,8H),0.89(t,J=7.2Hz,3H),0.83(t,J=6.0Hz,3H),0.77–0.73(m,3H).

[0082] 13 C NMR (100 MHz, CDCl 3 )δ214.6,214.5,194.9,166.8,140.6,140.5,138.7,138.6,132.0,129.9,128.9,128.4,127.8,126.3,109.78,109.76,108.3,108.2 ,52.1,37.65,37.57,35.04,34.95,32.8,32.6,31.8,28.93,28.88,28.6,28.1,25.9,25.6,23.0,22.9,22.5,14.1,14.0,10.8,10.5.

[0083] Implementation Case 8

[0084] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2f), and benzoyl fluoride (3a) as raw materials (Reaction formula 8)

[0085]

[0086] Under argon atmosphere, 1,4-dihydropyridine substrate 2f (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3a (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4be was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0087] The product detection data are as follows: solid, yield 43%, dr = 1.2:1.

[0088] 1 H NMR (400 MHz, CDCl 3 )δ8.06(d,J=8.4Hz,2H),7.61–7.57(m,2H),7.43–7.40(m,3H),7.24–7.18(m,2H),3.94(s,3H),3.80–3.75(m,1H),3.66–3.59(m,1H), 3.31–3.15(m,1H),2.64–2.47(m,4H),2.33–2.28(m,1H),1.92–1.82(m,1H),1.60–1.55(m,2H),1.47–1.32(m,6H),0.91–0.87(m,3H).

[0089] 13 C NMR (100 MHz, CDCl 3 )δ214.22,214.17,194.6,166.7,139.9,138.5,132.1,130.1,129.2,128.33,128.31,127.9,126.1,110.9 ,110.8,108.2,108.1,67.7,52.2,37.5,37.4,34.6,34.5,32.2,32.1,31.8,28.9,28.8,28.0,22.5,14.0.

[0090] Implementation Case 9

[0091] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3b) as raw materials (reaction formula 9)

[0092]

[0093] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3b (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nm LED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4ca was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0094] The product detection data are as follows: solid, yield 71%.

[0095] 1 H NMR (400 MHz, CDCl 3 )δ8.02(d,J=8.4Hz,2H),7.55(d,J=8.0Hz,2H),7.40(d,J=8.4Hz,2H),7.02(d,J=8.0Hz,2H),3.92(s,3H),2.58–2.52(m,2H),2 .42–2.37(m,1H),2.30(s,3H),2.28–2.22(m,1H),1.76–1.73(m,1H),1.61–1.55(m,2H),1.42–1.31(m,4H),0.90–0.84(m,9H).

[0096] 13 C NMR (100 MHz, CDCl 3 )δ213.8,194.3,166.7,142.7,140.5,135.9,129.9,128.8,128.6,128.5,126.3 ,109.4,107.8,52.1,39.8,31.7,29.1,28.1,27.0,22.6,22.4,22.3,21.4,14.0.

[0097] Implementation Case 10

[0098] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3c) as raw materials (reaction formula 10):

[0099]

[0100] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3c (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4cb was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0101] The product detection data are as follows: solid, yield 79%.

[0102] 1 H NMR (400 MHz, CDCl 3 )δ8.02(d,J=8.4Hz,2H),7.67(d,J=8.8Hz,2H),7.41(d,J=8.4Hz,2H),6.70(d,J=8.8Hz,2H),3.92(s,3H),3.77(s,3H).2.60–2 .50(m,2H),2.44–2.38(m,1H),2.29–2.23(m,1H),1.77–1.74(m,1H),1.60–1.57(m,2H),1.42–1.33(m,4H),0.90–0.84(m,9H).

[0103] 13 C NMR (100 MHz, CDCl 3 )δ213.1,193.1,166.8,162.9,140.6,131.1,130.9,129.9,128.8,126.3,113.1 ,109.2,107.6,55.3,52.1,39.8,31.7,29.3,28.2,27.0,22.7,22.4,22.3,14.0.

[0104] Implementation Case 11

[0105] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3d) as raw materials (reaction formula 11):

[0106]

[0107] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3d (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4cc was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0108] The product detection data are as follows: solid, yield 75%.

[0109] 1 H NMR (400 MHz, CDCl 3 )δ8.04(d,J=8.8Hz,2H),7.20(d,J=8.4Hz,2H),7.56–7.53(m,2H),7.47–7.40(m,6H),7.37–7.33(m,1H),3.93(s,3H),2.66–2 .52(m,2H),2.45–2.39(m,1H),2.31–2.25(m,1H),1.81–1.71(m,1H),1.68–1.57(m,2H),1.47–1.34(m,4H),0.93–0.85(m,9H).

[0110] 13 C NMR (100 MHz, CDCl 3 )δ214.2,194.3,166.7,144.7,140.4,139.9,137.3,129.9,129.1,129.0,128.8,128.0,127 .1,126.5,126.4,109.6,108.1,52.1,39.8,31.8,29.0,28.1,27.0,22.6,22.5,22.3,14.0.

[0111] Implementation Case 12

[0112] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3e) as raw materials (reaction formula 12)

[0113]

[0114] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3e (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4cd was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0115] The product detection data are as follows: solid, yield 68%.

[0116] 1 H NMR (400 MHz, CDCl 3 )δ8.03(d,J=8.4Hz,2H),7.54(d,J=8.4Hz,2H),7.38(d,J=8.4Hz,2H),7.17(d,J=8.8Hz,2H),3.91(s,3H),2.57–2.51(m,2 H),2.42–2.19(m,2H),1.75–1.68(m,1H),1.62–1.55(m,2H),1.41–1.31(m,4H),0.88(t,J=6.8Hz,3H),0.85–0.82(m,6H).

[0117] 13 C NMR (100 MHz, CDCl 3 )δ214.4,193.4,166.6,140.0,138.2,136.8,130.0,129.8,129.1,128.1,126 .3,109.5,108.4,52.1,39.8,31.7,28.8,28.1,26.9,22.6,22.4,22.2,14.0.

[0118] Example 13: Using enyne substrate (1a), 1,4-dihydropyridine substrate (2a), and benzoyl fluoride (3f) as raw materials (Reaction Formula 13)

[0119]

[0120] Under argon atmosphere, 1,4-dihydropyridine substrate 2a (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3f (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4ce was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0121] The product detection data are as follows: solid, yield 72%.

[0122] 1 H NMR (400 MHz, CDCl 3 )δ8.03(d,J=8.4Hz,2H),7.46(d,J=8.4Hz,2H),7.39–7.33(m,4H),3.92(s,3H),2.57–2.51(m,2H),2.43–2.1 9(m,2H),1.76–1.69(m,1H),1.61–1.55(m,2H),1.41–1.29(m,4H),0.88(t,J=7.2Hz,3H),0.85–0.82(m,6H).

[0123] 13 C NMR (100 MHz, CDCl 3 )δ214.5,193.6,166.6,140.0,137.3,131.0,130.0,129.9,129.1,126.8,126 .3,109.5,108.4,52.1,39.8,31.7,28.8,28.1,26.9,22.6,22.4,22.2,14.0.

[0124] Implementation Case 14

[0125] Using enyne substrate (1a), 1,4-dihydropyridine substrate (2c), and benzoyl fluoride (3e) as raw materials (reaction formula 14):

[0126]

[0127] Under argon atmosphere, 1,4-dihydropyridine substrate 2c (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3e (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4da was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0128] The product detection data are as follows: solid, yield 71%.

[0129] 1 H NMR (400 MHz, CDCl 3 )δ8.03(d,J=8.4Hz,2H),7.53(d,J=8.4Hz,2H),7.38(d,J=8.8Hz,2H),7.18(d,J=8.4Hz,2H),3.93(s,3H),2.57–2.49(m,2H),2.3 9–2.34(m,1H),2.27–2.22(m,1H),1.62–1.54(m,6H),1.52–1.47(m,1H),1.43–1.27(m,5H),1.11–1.02(m,3H),0.91–0.79(m,5H).

[0130] 13 C NMR (100 MHz, CDCl 3 )δ214.7,193.6,166.7,140.1,138.2,137.0,130.0,129.8,129.1,128.1,126.3,10 9.6,108.0,52.2,38.3,36.5,33.4,33.1,31.7,28.7,28.1,26.2,26.0,22.5,14.0.

[0131] Example 15: Using enyne substrate (1a), 1,4-dihydropyridine substrate (2c), and benzoyl fluoride (3f) as raw materials (Reaction Formula 15)

[0132]

[0133] Under argon atmosphere, 1,4-dihydropyridine substrate 2c (0.2mmol, 2.0equiv.), photocatalyst (0.002mmol, 0.02equiv.), nitrogen heterocyclic carbene (0.02mmol, 0.2equiv.), cesium carbonate (0.1mmol, 1.0equiv.) were added to a dry 10mL reaction tube, and solvent acetonitrile (2mL) was added, and then ene yne substrate 1a (0.1mmol, 1equiv.) and benzoyl fluoride substrate 3f (0.35mmol, 3.5equiv.) were added to the reaction tube. The reaction was placed at room temperature and stirred under 12W460nmLED blue light until the raw materials disappeared. After the reaction was completed, the reaction solution was filtered with diatomaceous earth, the solvent was dried under vacuum, and the target product 4db was purified and separated by column chromatography (eluent was petroleum ether: ethyl acetate = 40:1).

[0134] The product detection data are as follows: solid, yield 65%.

[0135] 1 H NMR (400 MHz, CDCl 3 )δ8.03(d,J=8.4Hz,2H),7.49–7.37(m,3H),7.20–7.18(m,1H),7.13–7.09(m,1H),3.93(s,3H),2.56–2.51(m,2H),2.37–2.32(m,1H) ,2.26–2.20(m,1H),2.08(s,3H),1.63–1.50(m,7H),1.43–1.30(m,5H),1.09–1.02(m,3H),0.90(t,J=6.8Hz,3H),0.84–0.79(m,2H).

[0136] 13 C NMR (100 MHz, CDCl 3 )δ214.7,195.3,166.8,140.6,138.7,137.4,132.7,129.9,129.2,128.8,127.7,126.4,125.4,1 09.7,107.5,52.1,38.2,36.6,33.4,33.1,31.8,28.8,28.1,26.2,26.1,26.1,22.5,20.9,14.0.

Claims

1. A method for synthesizing 1,2-alkenyl ketone, characterized in that enyne, 1,4-dihydropyridine and benzoyl fluoride are used as substrates, 2,4,5,6-tetrakis(diphenylamino)-isophthalonitrile is used as a photocatalyst, 5,6,7,8-tetrahydro-3-(2,6-diisopropylphenyl)-4H-cycloheptanthiazole perchlorate is used as a nitrogen heterocyclic carbene, cesium carbonate is used as a base, acetonitrile is used as a solvent, and the reaction is carried out at room temperature for 4 hours under visible light 12W460nm LED blue light to obtain alkenyl ketone, and the reaction formula is as follows: Where R 1 is selected from phenyl, pyridyl, methyl benzoate; R 2 is selected from n-pentyl; R 3 is selected from isopropyl, isobutyl, cyclopentyl, cyclohexyl, oxacyclopentyl, 1-methylbenzyl, 1-ethylpentyl; R 4 Selected from methyl, methoxy, phenyl, chloro, bromo.

2. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The photocatalyst used is selected from 2,4,5,6-tetrakis(diphenylamino)-isophthalonitrile.

3. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The nitrogen heterocyclic carbene used is selected from 5,6,7,8-tetrahydro-3-(2,6-diisopropylphenyl)-4H-cycloheptanthiazole perchlorate.

4. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The base used is selected from cesium carbonate.

5. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The solvent used is selected from acetonitrile.

6. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The temperature used was selected to be 25°C, maintained for 4 hours.

7. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The visible light used is selected from 12W 460nm LED blue light, and the duration is 4 hours.

8. The method for synthesizing 1,2-alkenyl ketone according to claim 1, characterized in that: The molar mass ratio of each substance in the reaction is selected from: ene yne: 1,4-dihydropyridine: benzoyl fluoride: photocatalyst: nitrogen heterocyclic carbene: base = 1:2:3.5:0.02:0.2:1.

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