Preparation method of aryl / heteroaryl ketone compound

Abstract

The invention discloses a preparation method of aryl / heteroaryl ketone compounds, and relates to the technical field of organic photoelectric synthesis. The technical problem that in-situ activation of aryl / heteroaryl formic acid and dehydroxymethyl coupling of alcohol compounds are difficult to prepare aryl / heteroaryl ketone compounds in the prior art is solved. The method comprises the following steps: continuously illuminating in a reaction system, introducing a constant current, carrying out light excitation on carboxylic acid and an alcohol compound as reactants at an anode through an iron catalyst, simultaneously carrying out in-situ activation on a nickel catalyst and carboxylic acid at a cathode, and then carrying out a reduction elimination process to obtain the aryl / heteroaryl ketone compound. According to the method, electrons provided by current in a system are used as a cheap and clean oxidizing agent, the use of an additional oxidizing agent is avoided, the reaction operation is simple, the condition is mild, and the prepared aryl / heteroaryl ketone compound is applied to the field of medicines.

Description

Technical Field

[0001] The invention relates to the technical field of organic photoelectric synthesis, and in particular to a method for preparing an aryl / heteroaryl ketone compound. Background Art

[0002] Aryl / heteroaryl ketone compounds are widely found in drugs, natural products, and agricultural products. Their synthesis is a very important topic in chemical research, especially in that heteroaryl ketone compounds are important components of many drug molecules. For example, progesterone is an important hormone that participates in the female menstrual cycle of humans and other animals, supports pregnancy and embryo formation, and is also the most important progestin known. Furan diterpenoid compounds are antibacterial and anti-inflammatory drugs. Ketotifen has the effect of preventing attacks of exogenous, endogenous, and mixed asthma.

[0003] The reaction of alcohols and carboxylic acid compounds to form ketone compounds has important academic and application value. Ketone compounds are the basic structural units in organic synthesis and are widely used in the fields of medicine, fragrance, materials and pesticides. Traditional methods for the synthesis of ketone compounds usually rely on complex reaction conditions and expensive catalysts, and often require the use of metal catalysts or strong redox reagents, which not only increases the cost of synthesis, but also brings environmental burden. Therefore, the development of a simple, efficient and environmentally friendly synthetic route, especially through the coupling reaction of carboxylic acids and alcohol compounds, has become an important research direction in the current field of organic chemistry. This reaction can not only provide new synthetic strategies, but also reduce the dependence on toxic reagents, improve the sustainability of the reaction, and has broad industrial application prospects. Summary of the invention

[0004] The present invention solves the technical problem that it is difficult to realize the in-situ activation of aromatic / heteroaromatic carboxylic acid and the dehydroxymethylation coupling of alcohol compounds to prepare aromatic / heteroaromatic ketone compounds in the existing reaction technology, and provides a method for preparing aromatic / heteroaromatic ketone compounds. The present invention uses a photoelectrochemical synthesis strategy, continuously illuminates the reaction system and passes a constant current, takes simple carboxylic acids and alcohol compounds as reactants, and forms alkoxy radicals through a ligand-to-metal charge transfer process after the iron catalyst is photoexcited at the anode, and the alkoxy radical intermediate then undergoes a β-CC bond break to obtain an alkyl radical, and at the same time, an oxidative addition process occurs at the cathode between the nickel catalyst and the acid anhydride generated by the in-situ activation of the carboxylic acid to form an intermediate of an aromatic / heteroaromatic acyl nickel compound, and then the intermediate captures the alkyl radical, and then a reduction elimination process occurs to obtain an aromatic / heteroaromatic alkyl ketone product, and at the same time, the catalytic cycle of the nickel catalyst is completed through a change in valence state.

[0005] A method for preparing an aryl / heteroaryl ketone compound is specifically carried out according to the following steps:

[0006] 1. Place an anode electrode and a cathode electrode in a quartz tube, add a carboxylic acid compound, an alcohol compound, diethyl pyrocarbonate, an iron catalyst, a nickel catalyst, a ligand and TBACl under an inert gas atmosphere, and then add an ultra-dry solvent to seal the system;

[0007] The carboxylic acid compound has the general structural formula:

[0008] wherein Ar represents an aryl or heteroaryl group;

[0009] 2. Continuously irradiate the closed system in step 1 under light with a wavelength of 390-395 nm, while continuously passing a constant current and stirring to obtain a crude product;

[0010] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain an aryl / heteroaryl ketone compound.

[0011] Furthermore, the alcohol compound in step 1 has the general structural formula: wherein R is an aryl group or an alkyl group.

[0012] Furthermore, the TBACl in step 1 is electrolyte tetrabutylammonium chloride.

[0013] Furthermore, the ultra-dry solvent in step 1 is ultra-dry acetone.

[0014] Furthermore, the iron catalyst in step 1 is ferrous chloride tetrahydrate; and the nickel catalyst is nickel (II) chloride ethylene glycol dimethyl ether complex.

[0015] Furthermore, the ligand in step 1 is 1,10-phenanthroline.

[0016] Furthermore, the amount ratio of the carboxylic acid compound to the ultra-dry solvent in step 1 is 0.2mmol:3mL; the amount ratio of the alcohol compound to the ultra-dry solvent is 0.6mmol:3mL; the amount ratio of diethyl pyrocarbonate to the ultra-dry solvent is 0.4mmol:3mL; the amount ratio of the iron catalyst to the ultra-dry solvent is 0.02mmol:3mL; the amount ratio of the nickel catalyst to the ultra-dry solvent is 0.03mmol:3mL; the amount ratio of the ligand to the ultra-dry solvent is 0.02mmol:3mL; the amount ratio of TBACl to the ultra-dry solvent is 0.4mmol:3mL.

[0017] Furthermore, in step 1, the anode electrode is a carbon felt electrode, and the cathode electrode is a carbon felt electrode, and the specifications of the carbon felt electrode are 15 mm×10 mm×2.0 mm.

[0018] Furthermore, in step 2, the current of the constant current is controlled to be 4 mA, the temperature of the condensation pump connected to the photoreactor is 16° C., the continuous power-on and illumination time is 12 hours; and TLC is used to monitor the reaction progress.

[0019] Furthermore, the solvent used for the thin layer chromatography separation and purification in step 3 is a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 20:1.

[0020] The general reaction formula of the present invention is as follows:

[0021]

[0022] Wherein R is an alkyl group or an aryl group.

[0023] The reaction mechanism of the present invention is shown in FIG. Figure 3 shown.

[0024] Initially, the process starts with the Fe(III) complex (A), which is excited by light to produce its excited state. III Cl4] - The catalyst undergoes a ligand-to-metal charge transfer (LMCT) process to generate alkoxy radicals, which then undergo a β-CC bond cleavage process to form an activated carbon-centered radical intermediate (C), while [Fe II Cl3] - Oxidized at the anode to recover [Fe III Cl4] - The cycle is completed. At the same time, the Ni(II) catalyst precursor is reduced in situ to generate Ni(I) species (D), and the intermediate D is further oxidized and added with the anhydride to form an acyl Ni(III) species (E), which is reduced to an acyl Ni(II) species (F) at the cathode. The carbon-centered free radical is captured by the Ni(II) intermediate F to generate a Ni(III) species (G), which is then subjected to a reduction elimination process to obtain the target ketone product, while forming a Ni(I) species (D) to complete the cycle.

[0025] Beneficial effects of the present invention:

[0026] Compared with the prior art, the present invention synthesizes aryl / heteroaryl ketone compounds by a simple, green and efficient method, which mainly has the following advantages:

[0027] (1) The reaction uses the electrons provided by the current in the system as a cheap and clean oxidant, avoiding the use of external oxidants. The reaction operation is simple and the conditions are mild.

[0028] (2) The carboxylic acid compound, alcohol compound, diethyl pyrocarbonate, iron catalyst, nickel catalyst, ligand, TBACl and ultra-dry solvent used in the reaction system are all simple, cheap and readily available commercial compounds, and the carbon felt electrode used is also a relatively cheap electrode sheet, making the reaction system simple and economical.

[0029] (3) The reaction system has a wide range of substrate applications and can be used to synthesize a variety of aromatic / heteroaromatic ketone compounds. The reaction substrates may include aromatic / heteroaromatic carboxylic acid compounds, aromatic alcohol compounds, or alkyl alcohol compounds.

[0030] The aryl / heteroaryl ketone compounds prepared by the invention are used in the field of medicine. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The heteroaryl ketone compound (3-1) obtained in Example 1 1 H NMR spectrum;

[0032] Figure 2 The heteroaryl ketone compound (3-1) obtained in Example 1 13 C NMR spectrum;

[0033] Figure 3 It is the reaction mechanism diagram of the present invention. DETAILED DESCRIPTION

[0034] Specific implementation method 1: This implementation method is a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0035] 1. Place an anode electrode and a cathode electrode in a quartz tube, add a carboxylic acid compound, an alcohol compound, diethyl pyrocarbonate, an iron catalyst, a nickel catalyst, a ligand and TBACl under an inert gas atmosphere, and then add an ultra-dry solvent to seal the system;

[0036] The carboxylic acid compound has the general structural formula:

[0037] wherein Ar represents an aryl or heteroaryl group;

[0038] 2. Continuously irradiate the closed system in step 1 under light with a wavelength of 390-395 nm, while continuously passing a constant current and stirring to obtain a crude product;

[0039] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain an aryl / heteroaryl ketone compound.

[0040] Specific embodiment 2: This embodiment is different from the specific embodiment 1 in that: the alcohol compound in step 1 has the general structural formula: Wherein R is an aryl group or an alkyl group. The rest is the same as the first embodiment.

[0041] Specific embodiment 3: This embodiment is different from specific embodiment 1 or 2 in that: the TBACl in step 1 is electrolyte tetrabutylammonium chloride. The rest is the same as specific embodiment 1 or 2.

[0042] Specific embodiment 4: This embodiment differs from any one of specific embodiments 1 to 3 in that the ultra-dry solvent in step 1 is ultra-dry acetone. The rest is the same as any one of specific embodiments 1 to 3.

[0043] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that: the iron catalyst in step 1 is ferrous chloride tetrahydrate; the nickel catalyst is nickel (II) chloride ethylene glycol dimethyl ether complex. The rest is the same as specific embodiments 1 to 4.

[0044] Specific embodiment 6: This embodiment is different from specific embodiments 1 to 5 in that the ligand in step 1 is 1,10-phenanthroline. The rest is the same as specific embodiments 1 to 5.

[0045] Specific embodiment seven: This embodiment differs from specific embodiments one to six in that: in step one, the ratio of the carboxylic acid compound to the ultra-dry solvent is 0.2mmol:3mL; the ratio of the alcohol compound to the ultra-dry solvent is 0.6mmol:3mL; the ratio of diethyl pyrocarbonate to the ultra-dry solvent is 0.4mmol:3mL; the ratio of the iron catalyst to the ultra-dry solvent is 0.02mmol:3mL; the ratio of the nickel catalyst to the ultra-dry solvent is 0.03mmol:3mL; the ratio of the ligand to the ultra-dry solvent is 0.02mmol:3mL; the ratio of TBACl to the ultra-dry solvent is 0.4mmol:3mL. Others are the same as specific embodiments one to six.

[0046] Specific embodiment 8: This embodiment differs from specific embodiments 1 to 7 in that the anode electrode in step 1 is a carbon felt electrode, the cathode electrode is a carbon felt electrode, and the specification of the carbon felt electrode is 15mm×10mm×2.0mm. The rest is the same as specific embodiments 1 to 7.

[0047] Specific embodiment 9: This embodiment is different from specific embodiments 1 to 8 in that: the current used to control the constant current in step 2 is 4 mA, the temperature of the condensation pump connected to the photoreactor is 16° C., the continuous power-on and light-irradiation time is 12 hours, and TLC is used to monitor the reaction progress. Others are the same as specific embodiments 1 to 8.

[0048] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that the solvent used for separation and purification by thin layer chromatography in step 3 is a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 20:1. The rest is the same as specific embodiments 1 to 9.

[0049] The content of the present invention is not limited to the content of the above-mentioned embodiments. The combination of one or several specific embodiments can also achieve the purpose of the invention.

[0050] Embodiment 1:

[0051] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0052] 1. Place two carbon felt electrodes in a 10 mL quartz tube and add 0.2 mmol 3-thiophenecarboxylic acid, 0.6 mmol β-phenylethanol, 0.4 mmol diethyl pyrocarbonate, and 0.02 mmol FeCl in an inert gas atmosphere. 2. 4H2O, 0.03mmolNiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0053] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0054] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as a heteroaryl ketone compound (3-1) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and its structural formula is:

[0055]

[0056] Purity 99%, yield 48%; its NMR data analysis is:

[0057] 1 H NMR (400MHz, Chloroform-d) δ 8.10 (dd, J = 2.9, 1.3 Hz, 1H), 7.57 (dd, J = 5.1, 1.2 Hz, 1H), 7.36-7.31 (m, 2H), 7.31-7.24 (m, 4H), 4.18 (s, 2H).

[0058] 13C NMR (101MHz, Chloroform-d) δ191.99,141.90,134.50,132.78,129.48,128.79,127.40,127.05,126.48,46.99.

[0059] Embodiment 2:

[0060] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0061] 1. Add 0.2 mmol 1-methyl-1H-pyrrole-2-carboxylic acid, 0.6 mmol β-phenylethanol, 0.4 mmol diethyl pyrocarbonate, and 0.02 mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0062] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0063] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as a heteroaryl ketone compound (3-2) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and has the structural formula:

[0064]

[0065] Purity 99%, yield 58%; its NMR data analysis is:

[0066] 1 H NMR (400MHz, Chloroform-d) δ7.37-7.28(m,4H),7.28-7.21(m,1H),7.09-7.08(M,1H),6.82-6.81(M,1H),6.15-6.14(M,1H),4.07(s,2H),3.91(s,3H).

[0067] 13 C NMR (101MHz, Chloroform-d) δ188.47,135.62,131.59,129.51,128.60,126.77,120.00,108.18,46.03,37.85.

[0068] Embodiment 3:

[0069] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0070] 1. Add 0.2 mmol 3-furancarboxylic acid, 0.6 mmol β-phenylethanol, 0.4 mmol diethyl pyrocarbonate, and 0.02 mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0071] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0072] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as a heteroaryl ketone compound (3-3) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and its structural formula is:

[0073]

[0074] Purity 99%, yield 59%; its NMR data analysis is:

[0075] 1 H NMR (400MHz, Chloroform-d) δ7.94 (s, 1H), 7.34 (t, J = 1.7Hz, 1H), 7.27-7.24 (m, 1H), 7.20 (d, J = 6.5Hz, 4H), 6.70 (d, J = 1.9Hz, 1H), 3.97 (s, 2H).

[0076] 13 C NMR (101MHz, Chloroform-d) δ192.42,147.74,144.24,134.32,129.43,128.82,127.15,109.05,47.68.

[0077] Embodiment 4:

[0078] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0079] 1. Add 0.2mmol 1-methyl-4-indolecarboxylic acid, 0.6mmol β-phenylethanol, 0.4mmol diethyl pyrocarbonate, and 0.02mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0080] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0081] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as a heteroaryl ketone compound (3-4) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and has the structural formula:

[0082]

[0083] Purity 99%, yield 59%; its NMR data analysis is:

[0084] 1 H NMR(400MHz,Chloroform-d)δ7.87-7.85(m,1H),7.54(d,J=8.2Hz,1H),7.35-7 .29(m,5H),7.28-7.23(m,2H),7.20(d,J=3.1Hz,1H),4.41(s,2H),3.82(s,3H).

[0085] 13 C NMR (101MHz, Chloroform-d) δ198.99,137.76,135.52,131.94,129.67,128.63,126.72,123.06,120.55,114.62,103.01,46.31,33.08.

[0086] Embodiment 5:

[0087] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0088] 1. Add 0.2 mmol benzoxazole-5-carboxylic acid, 0.6 mmol β-phenylethanol, 0.4 mmol diethyl pyrocarbonate, and 0.02 mmol FeCl in an inert gas atmosphere. 2.4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0089] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0090] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as a heteroaryl ketone compound (3-5) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and has the structural formula:

[0091]

[0092] Purity 99%, yield 65%; its NMR data analysis is:

[0093] 1 H NMR(400MHz,Chloroform-d)δ7.87-7.85(m,1H),7.54(d,J=8.2Hz,1H),7.35-7 .29(m,5H),7.28-7.23(m,2H),7.20(d,J=3.1Hz,1H),4.41(s,2H),3.82(s,3H).

[0094] 13 C NMR (101MHz, Chloroform-d) δ198.99,137.76,135.52,131.94,129.67,128.63,126.72,123.06,120.55,114.62,103.01,46.31,33.08.

[0095] Embodiment 6:

[0096] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0097] 1. Add 0.2mmol benzoic acid, 0.6mmol 4-chloro-2-phenylethanol, 0.4mmol diethyl pyrocarbonate, and 0.02mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2.glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0098] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0099] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as an aromatic ketone compound (3-6) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and has the structural formula:

[0100]

[0101] Purity 99%, yield 58%; its NMR data analysis is:

[0102] 1 H NMR(400MHz,Chloroform-d)δ7.99(d,J=7.1Hz,2H),7.61-7.54(m,1H),7.47(d d,J=8.4,7.0Hz,2H),7.30(d,J=8.4Hz,2H),7.19(d,J=8.4Hz,2H),4.26(s,2H).

[0103] 13 C NMR (101MHz, Chloroform-d) δ197.17,136.49,133.42,132.99,130.95,128.86,128.79,128.58,44.74.

[0104] Embodiment 7:

[0105] 1. Add 0.2 mmol benzoic acid, 0.6 mmol 4-methoxy-2-phenylethanol, 0.4 mmol diethyl pyrocarbonate, and 0.02 mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0106] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0107] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as an aromatic ketone compound (3-7) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and its structural formula is:

[0108]

[0109] Purity 99%, yield 42%; its NMR data analysis is:

[0110] 1 H NMR(400MHz,Chloroform-d)δ8.01(d,J=7.1Hz,2H),7.59-7.52(m,1H),7.45(t,J= 8.0Hz,2H),7.18(d,J=6.5Hz,2H),6.86(d,J=8.7Hz,2H),4.22(s,2H),3.78(s,3H).

[0111] 13 C NMR (101MHz, Chloroform-d) δ198.07,158.60,136.66,133.20,130.55,128.71,128.67,126.55,114.21,55.32,44.69.

[0112] Embodiment 8:

[0113] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0114] 1. Add 0.2mmol benzoic acid, 0.6mmol 4-cyano-phenylethanol, 0.4mmol diethyl pyrocarbonate, and 0.02mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0115] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0116] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as an aromatic ketone compound (3-8) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and has the structural formula:

[0117]

[0118] Purity 99%, yield 42%; its NMR data analysis is:

[0119] 1 H NMR (400MHz, Chloroform-d) δ8.01-8.00(m,2H),7.67-7.58(m,3H),7.52-7.48(m 2H),7.39-7.37(m,2H),4.37(s,2H).

[0120] 13 C NMR (101MHz, Chloroform-d) δ196.24,140.03,136.24,133.77,132.42,130.61,128.94,128.52,118.87,111.02,45.28.

[0121] Embodiment 9:

[0122] This embodiment provides a method for preparing an aryl / heteroaryl ketone compound, which is specifically carried out according to the following steps:

[0123] 1. Add 0.2 mmol benzoic acid, 0.6 mmol cyclohexylmethanol, 0.4 mmol diethyl pyrocarbonate, and 0.02 mmol FeCl under an inert gas atmosphere. 2. 4H2O, 0.03mmol NiCl 2. glyme, 0.04mmol 1,10-phenanthroline and 0.4mmol TBACl, then add 3mL of ultra-dry acetonitrile solvent and seal the system;

[0124] 2. The closed system in step 1 was continuously irradiated under 390-395 nm light, and a constant current of 4 mA was continuously passed. The temperature of the condensation pump connected to the photoreactor was 16°C. The reaction was stirred for 12 h, and the reaction progress was monitored by TLC to obtain a crude product.

[0125] 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain a product, which is identified as an aromatic ketone compound (3-9) by nuclear magnetic resonance hydrogen spectrum, carbon spectrum and mass spectrum, and has the structural formula:

[0126]

[0127] Purity 99%, yield 36%; its NMR data analysis is:

[0128] 1 H NMR(400MHz,Chloroform-d)δ7.95(d,J=7.9Hz,2H),7.54(t,J=7.3Hz,1H),7.46(t,J=7.6Hz,2H),3. 27(tt,J=11.5,3.2Hz,1H),1.87(td,J=18.2,17.3,3.4Hz,4H),1.79-1.70(m,1H),1.58-1.21(m,5H).

[0129] 13 C NMR (101MHz, Chloroform-d) δ204.01,136.40,132.80,128.65,128.32,45.69,29.48,26.02,25.92.

[0130] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A method for preparing an aryl / heteroaryl ketone compound, characterized in that The method is specifically carried out in the following steps:

1. Place an anode electrode and a cathode electrode in a quartz tube, add a carboxylic acid compound, an alcohol compound, diethyl pyrocarbonate, an iron catalyst, a nickel catalyst, a ligand and TBACl under an inert gas atmosphere, and then add an ultra-dry solvent to seal the system; The carboxylic acid compound has the general structural formula: wherein Ar represents an aryl or heteroaryl group; 2. Continuously irradiate the closed system in step 1 under light with a wavelength of 390-395 nm, while continuously passing a constant current and stirring to obtain a crude product; 3. The crude product obtained in step 2 is subjected to reduced pressure distillation to remove the solvent, and then separated and purified by thin layer chromatography to obtain an aryl / heteroaryl ketone compound.

2. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that The alcohol compound in step 1 has the general structural formula: wherein R is an aryl group or an alkyl group.

3. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that The TBACl in step 1 is electrolyte tetrabutylammonium chloride.

4. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that The ultra-dry solvent in step 1 is ultra-dry acetone.

5. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that In step 1, the iron catalyst is ferrous chloride tetrahydrate; and the nickel catalyst is nickel (II) chloride ethylene glycol dimethyl ether complex.

6. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that The ligand in step 1 is 1,10-phenanthroline.

7. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that In step 1, the dosage ratio of the carboxylic acid compound to the ultra-dry solvent is 0.2mmol:3mL; the dosage ratio of the alcohol compound to the ultra-dry solvent is 0.6mmol:3mL; the dosage ratio of diethyl pyrocarbonate to the ultra-dry solvent is 0.4mmol:3mL; the dosage ratio of the iron catalyst to the ultra-dry solvent is 0.02mmol:3mL; the dosage ratio of the nickel catalyst to the ultra-dry solvent is 0.03mmol:3mL; the dosage ratio of the ligand to the ultra-dry solvent is 0.02mmol:3mL; and the dosage ratio of TBACl to the ultra-dry solvent is 0.4mmol:3mL.

8. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that The anode electrode in step 1 is a carbon felt electrode, and the cathode electrode is a carbon felt electrode. The specifications of the carbon felt electrode are 15 mm×10 mm×2.0 mm.

9. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that Step 2: The current of the constant current is controlled to be 4 mA, the temperature of the condensation pump connected to the photoreactor is 16° C., the continuous power-on and illumination time is 12 hours; and the reaction progress is monitored by TLC.

10. The method for preparing an aryl / heteroaryl ketone compound according to claim 1, characterized in that The solvent used for the thin layer chromatography separation and purification in step 3 is a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 20:1.

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