A method for synthesizing alpha-aryl cyclohexanone compounds

Abstract

The application relates to a synthesis method of an alpha-aryl cyclohexanone compound, and belongs to the technical field of photocatalytic organic synthesis, and comprises the following steps: taking aryl diazonium tetrafluoroborate and cyclohexene as raw materials, adding an additive, and under the condition that mixed solvents exist, alpha-aryl cyclohexanone is obtained through reaction under visible light irradiation and in the presence of a quantum dot catalyst; the application provides a brand-new synthesis path of aryl cyclohexanone compounds, adopts cheap aryl diazonium salt and cyclohexene as raw materials, and alpha-aryl cyclohexanone compounds are synthesized through photocatalysis under mild reaction conditions, so that the dependence on noble metal catalysts and harsh reaction conditions in traditional methods is avoided.

Description

Technical Field

[0001] This application relates to a method for synthesizing α-arylcyclohexanone compounds using visible light catalysis, belonging to the field of photocatalytic organic synthesis technology.

[0002] In this application, Zn2CuInS4 / ZnS QDs, Zn2CuInS4 / ZnS quantum dots, and Zn2CuInS4 / ZnS quantum dot catalysts have the same meaning. Background Technology

[0003] α-Arylcyclohexanone structures are widely found in many bioactive natural products and drug molecules, serving as crucial structural units in medicinal chemistry and organic synthesis (Org. Lett. 2010, 12, 1576-1579). α-Arylcyclohexanones also have significant industrial value because their oxidation products form the basis for the production of the bulk chemical ε-caprolactone (ACS Catal. 2022, 12, 66-72). Furthermore, the synthesis of α-arylcyclohexanol from α-arylcyclohexanones has important applications in chromatographic column chromatography.

[0004] Currently, established methods for synthesizing α-arylcyclohexanone mainly rely on the coupling reactions of aryl halides or pseudohalides with ketones catalyzed by transition metals (usually palladium containing sterically hindered monodentate phosphine and N-heterocyclic carbene ligands) (Angew. Chem., Int. Ed. 2010, 49, 676-707), and the cross-coupling reactions of α-halocarbonyl electrophiles with aromatic nucleophiles (such as arylboronic acids or organometallic reagents) catalyzed by transition metals (J. Am. Chem. Soc., 2011, 133, 13782). However, these traditional methods typically have significant limitations: they require expensive noble metal catalysts, complex ligands, strongly alkaline environments, and harsh reaction conditions such as high temperatures. Furthermore, many methods require pre-functionalized reagents, are cumbersome, and have low atom economy.

[0005] In recent years, visible light-induced redox catalysis has attracted much attention due to its green, mild, and sustainable characteristics. Although there have been reports of photocatalytic Maier-Wegen type reactions using Ru, Ir complexes, or organic dyes, developing a method for the direct synthesis of α-arylcyclohexanone from inexpensive and readily available raw materials (such as diazonium salts and unactivated olefins) without precious metals remains a significant challenge and has great application value. Against this backdrop, zinc-copper-indium-sulfur / zinc sulfide (Zn2CuInS4 / ZnS) core-shell quantum dots have shown great potential as an inexpensive, low-toxicity, and recyclable semiconductor photocatalyst. Summary of the Invention

[0006] The first objective of this application is to provide a method for synthesizing α-arylcyclohexanone compounds that uses readily available raw materials, is low in cost, and is environmentally friendly.

[0007] The technical solution adopted in this application is as follows:

[0008] A method for synthesizing α-arylcyclohexanone compounds, characterized by comprising the following steps: using aryldiazotetrafluoroborate and cyclohexene as raw materials, reacting them in the presence of additives, in the presence of a mixed solvent, under visible light irradiation, and in the presence of a quantum dot catalyst to obtain α-arylcyclohexanone compounds.

[0009] Further settings include:

[0010] The additive is one of tert-butyl hypochlorite, hydrochloric acid, tetrafluoroboric acid, lithium chloride, or lithium bromide. Preferred is tert-butyl hypochlorite (t-BuOCl). The addition of the additive is crucial for the reaction to proceed and can significantly improve the yield.

[0011] The visible light is blue light with a wavelength of 420-460 nm.

[0012] The mixed solvent is a mixture of acetonitrile, water, and dimethyl sulfoxide. The preferred volume ratio is acetonitrile:water:dimethyl sulfoxide = 7:2:1. This solvent system ensures good solubility of the reactants and maintains the excited-state activity of the quantum dots.

[0013] The quantum dot catalyst is Zn2CuInS4 / ZnS QDs.

[0014] The quantum dot catalyst Zn2CuInS4 / ZnS QDs was prepared by the following method: Cu(NO3)2·3H2O, In(NO3)3·4H2O, thiourea and ligands were dissolved in deionized water and mixed; sodium hydroxide was added to the above mixed solution to adjust the pH value of the solution to 10-11, and then the mixture was heated at 100-120℃ for 30-60 min; after cooling to room temperature, Zn(Ac)2·2H2O, thiourea and MPA were added to the above solution and sonicated for 1-10 min, and then heated at 100-120℃ for 0.5-2 h. After cooling to room temperature, the solution was centrifuged, washed and dried to obtain the quantum dot catalyst Zn2CuInS4 / ZnS QDs.

[0015] The amount of the quantum dot catalyst used is 1-5 g / mol relative to aryldiazotetrafluoroborate.

[0016] The preferred reaction temperature is room temperature.

[0017] The reaction equations involved in this application are as follows:

[0018]

[0019] A second objective of this application is to provide an α-arylcyclohexanone compound synthesized by the above method, the structural formula of which is as follows:

[0020] .

[0021] In the formula: the Ar group is selected from one of phenyl, substituted phenyl, naphthyl, and heteroaryl.

[0022] Furthermore, the substituents on the substituted phenyl group include, but are not limited to, nitro, methyl, methoxy, acetyl, benzoyl, amide, etc.

[0023] The following are examples of some specific compounds prepared in this application:

[0024] .

[0025] The third objective of this application is to provide the use of the above-mentioned α-arylcyclohexanone compounds in the preparation of antibacterial drugs.

[0026] The beneficial effects of this application are as follows:

[0027] (1) This application provides a novel synthetic route for α-arylcyclohexanone compounds, which utilizes inexpensive aryl diazonium salts and cyclohexene to directly synthesize α-arylcyclohexanone compounds in a mild aqueous medium, avoiding the dependence on noble metal catalysts (such as Pd) and harsh conditions in traditional methods.

[0028] (2) The Zn2CuInS4 / ZnS quantum dot catalyst used in this application is free of precious metals and highly toxic heavy metals (such as Cd), has low cost, and exhibits excellent photochemical stability and recyclability. Experiments have shown that the catalyst can still maintain high catalytic activity after 5 cycles, and its morphology and structure do not change significantly, showing good prospects for industrial application.

[0029] (3) The method of this application has good substrate versatility. Whether it is an aryl diazonium salt with an electron-withdrawing group or an electron-donating group, or even a heteroaryl diazonium salt, the target product can be obtained in a moderate to good yield. Attached Figure Description

[0030] Figure 1 The ultraviolet and fluorescence spectra of the quantum dot catalysts prepared for the embodiments of this application are shown.

[0031] Figure 2 The image shows the TEM spectrum of the quantum dot catalyst prepared in the embodiments of this application before cycling.

[0032] Figure 3The image shows the TEM spectrum of the quantum dot catalyst prepared in the embodiments of this application after cycling.

[0033] Figure 4 The bar chart shows the yield of the quantum dot catalyst prepared in the embodiments of this application.

[0034] Figure 5 Illustration of the antibacterial effect of the α-arylcyclohexanone compounds prepared in this application on Staphylococcus aureus. Detailed Implementation

[0035] The technical solution of this application is described in detail below with reference to specific embodiments. Unless otherwise specified, the raw materials and reagents used in the embodiments of this application are all commercially available analytical grade products.

[0036] In the following embodiments of this application, the quantum dot catalyst is prepared using the following method:

[0037] 0.2 mmol Cu(NO3)2·3H2O, 0.4 mmol In(NO3)3·4H2O, 0.2 mmol thiourea, and 2 mmol MPA ligand were dissolved in deionized water and mixed. Then, 1.0 mol / L sodium hydroxide was added to the mixture to adjust the pH to 10.0, resulting in a clear solution. The mixture was stirred for 5 min, then sealed in a 25 mL three-necked flask and heated at 110°C for 40 min to obtain the core solution. After cooling to room temperature, the prepared shell solution (0.2 mmol Zn(Ac)2·2H2O, 0.1 mmol thiourea, and 0.4 mmol MPA) was added to the hydrothermal reactor containing the core solution, sonicated for 5 min, and heated at 110 °C for 1 h. After cooling to room temperature, an aqueous solution of Zn2CuInS4 / ZnS quantum dots was obtained. Centrifugation yielded reddish-brown Zn2CuInS4 / ZnS quantum dots. The product was washed three times with ethanol and water and dried in a vacuum oven to obtain Zn2CuInS4 / ZnS quantum dot powder, which was labeled as catalyst 1.

[0038] The catalyst prepared above was subjected to a series of characterization analyses, such as fluorescence and ultraviolet light. Figure 1 As shown: This indicates that the prepared catalyst is uniformly dispersed and has a uniform size.

[0039] Example 1

[0040] This embodiment describes the synthesis of 2-(4-nitrophenyl)cyclohexanone, including the following steps:

[0041] In a clear glass vial equipped with a magnetic stir bar, a solvent mixture was added: dimethyl sulfoxide (DMSO, 0.2 mL), water (H₂O, 0.4 mL), and acetonitrile (CH₃CN, 1.4 mL). Subsequently, 4-nitrobenzenetetrafluoroborate diazonium salt (0.2 mmol), cyclohexene (1.0 mmol, 5 eq), tert-butyl hypochlorite (t-BuOCl, 0.4 mmol, 2 eq), and catalyst 1 (Zn₂CuInS₄ / ZnS quantum dots 3 mg) were added sequentially. The reaction mixture was placed at room temperature and irradiated with a 3 W blue LED lamp (wavelength 420 nm) while stirring for 5 hours. After the reaction was complete (monitored by TLC), the catalyst was separated by centrifugation, and the supernatant was concentrated and purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 5:1) to give 33.7 mg of a yellow oily liquid product, with a yield of 77%.

[0042] Product confirmation:

[0043] Compound name: 2-(4-nitrophenyl)cyclohexanone.

[0044] The structural formula is:

[0045] .

[0046] Product characterization: 1 HNMR (400 MHz, Chloroform-d) δ 8.26 – 8.19 (m, 2H), 7.36 –7.31 (m, 2H), 3.77 (dd, J = 12.7, 5.3 Hz, 1H), 2.64 – 2.49 (m, 2H), 2.34(ddt, J = 14.2, 5.9, 2.9 Hz, 1H), 2.24 (dtd, J = 10.5, 5.5, 4.7, 2.3 Hz, 1H), 2.12 – 1.99 (m, 2H), 1.93 – 1.84 (m, 2H). 13 CNMR (101 MHz, Chloroform-d) δ208.87, 146.99, 146.36, 129.69, 123.57, 57.34, 42.30, 35.29, 27.77, 25.39.HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 12 H 14 NO3 + 220.0968; Found 287.0973.

[0047] Example 2

[0048] To investigate the effect of different ligands on the catalytic effect of Zn2CuInS4 / ZnS quantum dots, catalyst 1 in Example 1 was replaced with catalysts 2-7, while other process conditions remained unchanged. The test results are shown in Table 1.

[0049] The preparation methods of catalysts 2-7 are the same as those of catalyst 1, except that the type and amount of ligand (2 mmol MPA) in the core solution are changed during catalyst synthesis, while the type and amount of ligand in the shell solution remain unchanged (0.4 mmol MPA).

[0050] Catalyst 2: The ligand is GSH (glutathione), and the dosage is 2 mmol.

[0051] Catalyst 3: The ligand is MSA (mercaptosuccinic acid), and the amount used is 2 mmol.

[0052] Catalyst 4: The ligand is CA (citric acid), and the amount used is 2 mmol.

[0053] Catalyst 5: The ligand is MPA (mercaptopropionic acid), and the amount used is 1 mmol.

[0054] Catalyst 6: The ligand is MPA (mercaptopropionic acid), and the amount used is 2.5 mmol.

[0055] Catalyst 7: The ligand is MPA (mercaptopropionic acid), and the amount used is 3 mmol.

[0056] Table 1

[0057] .

[0058] Example 3

[0059] This embodiment mainly examines the effects of different types of catalysts and their dosages on the reaction.

[0060] The preparation method is the same as in Example 1, except that the type and amount of catalyst are adjusted as shown in Table 2, and their effect on the yield is tested.

[0061] Table 2

[0062] .

[0063] Example 4

[0064] This example mainly examines the effects of different solvents and additives on the reaction.

[0065] The preparation method is the same as in Example 1, except that the composition of the solvent and the type of additives are adjusted as shown in Table 3, and their effects on the yield are tested.

[0066] Table 3

[0067] .

[0068] Example 5

[0069] This embodiment mainly examines the recyclability of the catalyst.

[0070] The catalyst separated by centrifugation in Example 1 was thoroughly washed and dried with ethanol / water, and then reintroduced into the reaction. The number of cycles and performance of the catalyst were tested, as shown in Table 4.

[0071] Table 4

[0072] .

[0073] like Figure 4 As shown in Table 4, at the end of the fifth catalytic operation, the product yield was 69%, and the catalytic activity did not decrease significantly. (Regarding the catalyst before recycling...) Figure 2 ) and after the loop ( Figure 3 TEM characterization revealed that the quantum dots maintained a good dispersion state with no drastic size aggregation. Some particles showed a slight increase in size, presumably due to trace Ostwald ripening caused by partial detachment of surface MPA ligands during cycling. However, this did not damage the core crystal structure, explaining why it maintained catalytic activity for more than five cycles. Therefore, it can be seen that the catalyst has good cycling performance and its activity does not decrease after multiple cycles, making it suitable for industrial production processes.

[0074] Example 6

[0075] This embodiment mainly focuses on the synthesis of 4-N-methyl-4-(2-oxocyclohexyl)benzamide.

[0076] The preparation method is the same as in Example 1, except that: 4-nitrobenzenetetrafluoroborate diazonium salt is replaced with 4-(N-methylformamido)benzenetetrafluoroborate diazonium salt (0.2 mmol), and the eluent ratio is adjusted to petroleum ether / ethyl acetate = 3:1, yielding 28.2 mg of brown oily liquid with a yield of 61%.

[0077] Product confirmation:

[0078] Compound name: 4-N-methyl-4-(2-oxocyclohexyl)benzamide.

[0079] Product structure:

[0080]

[0081] Product characterization: 1HNMR (400 MHz, Chloroform- d ) δ 7.74 (d, J = 8.1 Hz, 2H), 7.22(d, J = 7.9 Hz, 2H), 6.25 (s, 1H), 3.69 (dd, J = 12.5, 5.5 Hz, 1H), 3.03 (d, J =4.8 Hz, 3H), 2.60 – 2.48 (m, 2H), 2.31 (ddt, J = 12.2, 5.4, 2.7 Hz, 1H), 2.21(dtt, J = 9.3, 6.5, 3.1 Hz, 1H), 2.10 – 2.02 (m, 2H), 1.87 (ddt, J = 11.0, 5.9, 1.8 Hz, 2H).

[0082] 13 CNMR (101 MHz, Chloroform- d ) δ 209.95, 168.23, 142.32, 133.30,128.86, 126.95, 57.32, 42.71, 42.28, 35.15, 27.82, 26.87, 25.37, 1.07.

[0083] HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 14 H 18 ClNO2 + 232.1332; Found232.1342.

[0084] Example 7

[0085] This embodiment mainly focuses on the synthesis of 2-(thien-3-yl)cyclohexanone.

[0086] The preparation method was the same as in Example 1, except that 4-nitrophenyltetrafluoroborate diazonium salt was replaced with 2-thiophenetetrafluoroborate diazonium salt (0.2 mmol), and the eluent ratio was adjusted to petroleum ether / ethyl acetate = 5:1. 13.3 mg of a pale yellow oily liquid was obtained, with a yield of 37%.

[0087] Product confirmation:

[0088] Compound name: 2-(thien-3-yl)cyclohexanone.

[0089] Product structure:

[0090]

[0091] Product characterization: 1 HNMR (400 MHz, Chloroform- d ) δ 7.33 (dd, J = 5.0, 3.0 Hz,1H), 7.09 – 7.06 (m, 1H), 6.98 (dd, J = 5.0, 1.3 Hz, 1H), 3.76 (dd, J = 11.3, 5.4Hz, 1H), 2.59 – 2.41 (m, 2H), 2.39 – 2.29 (m, 1H), 2.13 (tdd, J = 9.8, 7.4, 3.9Hz, 1H), 2.02 (dddd, J = 15.4, 10.9, 5.7, 3.5 Hz, 2H), 1.88 – 1.80 (m, 2H).

[0092] 13 CNMR (101 MHz, Chloroform- d ) δ 210.19, 139.33, 127.98, 126.57,125.30, 125.18, 124.43, 121.47, 52.42, 52.07, 41.93, 41.72, 36.24, 34.83,27.85, 27.74, 25.00, 24.95.

[0093] HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 10 H 13 OS + 181.0682; Found181.0684.

[0094] Example 8

[0095] This embodiment mainly focuses on the synthesis of 2-(3-methoxy-4-nitrophenyl)cyclohexanone.

[0096] The preparation method was the same as in Example 1, except that 4-nitrophenyltetrafluoroborate diazonium salt was replaced with 3-methoxy-4-nitrophenyltetrafluoroborate diazonium salt (0.2 mmol), and the eluent ratio was adjusted to petroleum ether / ethyl acetate = 5:1. 28.9 mg of a pale yellow oily liquid was obtained, with a yield of 58%.

[0097] Product confirmation:

[0098] Compound name: 2-(3-methoxy-4-nitrophenyl)cyclohexanone.

[0099] Product structure:

[0100]

[0101] Product characterization: 1 HNMR (400 MHz, Chloroform- d ) δ 7.88 (dd, J = 8.3, 2.2 Hz, 1H), 7.75 (d, J = 2.2 Hz, 1H), 4.06 (dd, J = 13.0, 5.2 Hz, 1H), 3.91 (s, 3H), 2.60 – 2.50 (m, 2H), 2.30 – 2.19 (m, 2H), 2.14 – 2.00 (m, 2H), 1.95 – 1.81(m, 2H).

[0102] 13 CNMR (101 MHz, Chloroform- d ) δ 208.54, 157.37, 147.88, 135.62,129.17, 115.87, 105.40, 56.04, 51.04, 42.31, 33.22, 27.56, 25.56.

[0103] HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 13 H 16 NO4 + 250.1073; Found250.1071.

[0104] Example 9

[0105] This embodiment mainly focuses on the synthesis of 2-phenylcyclohexanone.

[0106] The preparation method was the same as in Example 1, except that 4-nitrobenzenetetrafluoroborate diazonium salt was replaced with benzenediazotetrafluoroborate (0.2 mmol), and the eluent ratio was adjusted to petroleum ether / ethyl acetate = 7:1. 19.8 mg of a white oily liquid was obtained, with a yield of 57%.

[0107] Product confirmation:

[0108] Compound name: 2-Phenylonhexanone.

[0109] Product structure:

[0110]

[0111] Product characterization: 1 HNMR (400 MHz, Chloroform-d) δ 7.49 – 7.11 (m, 5H), 3.67 (dd, J = 12.2, 5.4 Hz, 1H), 2.63 – 2.44 (m, 2H), 2.32 (ddt, J = 14.8, 4.5,2.6 Hz, 1H), 2.26 – 2.15 (m, 1H), 2.13 – 2.00 (m, 2H), 1.97 – 1.81 (m, 2H).

[0112] 13 CNMR (101 MHz, Chloroform- d ) δ 210.40, 138.86, 128.62, 128.41,126.95, 57.45, 42.27, 35.18, 27.90, 25.39.

[0113] HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 12 H 15 O + 175.1117; 175.1122.

[0114] Example 10

[0115] This embodiment mainly focuses on the synthesis of 4-(2-oxocyclohexyl)-N-phenylbenzamide.

[0116] The preparation method was the same as in Example 1, except that 4-nitrophenyltetrafluoroborate diazonium salt was replaced with 4-phenylcarbamoylphenyltetrafluoroborate diazonium salt (0.2 mmol), and the eluent ratio was adjusted to petroleum ether / ethyl acetate = 2:1. 47.5 mg of a brown oily liquid was obtained, with a yield of 81%.

[0117] Product confirmation:

[0118] Compound name: 4-(2-oxocyclohexyl)-N-phenylbenzamide.

[0119] Product structure:

[0120]

[0121] Product characterization: 1 HNMR (400 MHz, Chloroform-d) δ 7.87 (s, 1H), 7.81 (d, J =8.0 Hz, 3H), 7.64 (d, J = 7.9 Hz, 3H), 7.37 (t, J = 7.8 Hz, 3H), 7.24 (d, J =7.9 Hz, 2H), 7.14 (p, J = 4.9 Hz, 1H), 3.68 (dd, J = 12.6, 5.4 Hz, 1H), 2.53(m, 2H), 2.30 (dt, J = 10.7, 3.7 Hz, 1H), 2.25 – 2.15 (m, 1H), 2.03 (d, J =9.7 Hz, 3H), 1.86 (q, J = 11.4, 10.6 Hz, 3H).

[0122] 13 CNMR (101 MHz, Chloroform-d) δ 209.87, 142.87, 138.07, 133.75,129.12, 127.12, 124.52, 120.20, 57.39, 42.32, 35.15, 27.83, 25.40.

[0123] HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 19 H 20 NO2 + 294.1489; Found294.1482.

[0124] Example 11

[0125] This embodiment mainly focuses on the synthesis of 2-(benzo[b]thiophene-3-yl)cyclohexanone.

[0126] The preparation method was the same as in Example 1, except that 4-nitrobenzenetetrafluoroborate diazonium salt was replaced with 3-benzothiophene diazonium tetrafluoroborate (0.2 mmol), and the eluent ratio was adjusted to petroleum ether / ethyl acetate = 5:1. 23.4 mg of a white solid was obtained, with a yield of 51%.

[0127] Product confirmation:

[0128] Compound name: 2-(benzo[b]thiophen-3-yl)cyclohexanone.

[0129] Product structure:

[0130]

[0131] Product characterization: 1 HNMR (400 MHz, Chloroform-d) δ 7.93 – 7.87 (m, 1H), 7.62 –7.57 (m, 1H), 7.43 – 7.34 (m, 2H), 4.05 (dd, J = 12.0, 5.4 Hz, 1H), 2.67 –2.55 (m, 2H), 2.51 – 2.41 (m, 1H), 2.28 – 2.06 (m, 3H), 1.94 (dd, J = 9.9,2.6 Hz, 2H).

[0132] 13 CNMR (101 MHz, Chloroform-d) δ 209.30, 140.24, 138.66, 133.94,124.28, 123.94, 122.95, 122.92, 121.92, 51.04, 42.32, 34.23, 28.08, 25.50.

[0133] HRMS (ESI-TOF) m / z: [M + H] + Calcd for C 14 H 15 OS + 231.0838; Found.231.0835.

[0134] Application Example 1

[0135] This embodiment mainly investigates the antibacterial properties of the product 2-(3-methoxy-4-nitrophenyl)cyclohexanone.

[0136] Staphylococcus aureus was used as the test strain, and the antibacterial effect of the product was evaluated using the plate count method. The specific procedure was as follows: The concentration of bacterial suspension activated to the logarithmic growth phase (OD600 = 0.6-0.8) was adjusted to OD600 = 0.08 for later use. Gradient solutions (10, 0.5, 0.1 mg / mL) of the test sample were prepared using a DMSO / water solvent system. 50 μL of each concentration solution was mixed with an equal volume of bacterial suspension in sterile EP tubes to achieve final effective concentrations of 5, 0.25, and 0.05 mg / mL, respectively. A blank control was also included. The mixtures were spread onto solid agar plates and incubated inverted at 37°C overnight. The inhibition rate at different concentrations was calculated by counting the colonies (results are shown in Table 5).

[0137] Table 5

[0138] .

[0139] Combination Figure 5 As shown in Table 5, 2-(3-methoxy-4-nitrophenyl)cyclohexanone exhibits a strong inhibitory effect on Staphylococcus aureus, and its antibacterial activity is concentration-dependent. The bactericidal effect significantly increases with increasing concentration; at a concentration of 5.00 mg / mL, bacterial growth is completely inhibited, with an inhibition rate of 100%.

[0140] In summary, 2-(3-methoxy-4-nitrophenyl)cyclohexanone is a substance with highly efficient antibacterial activity against Gram-positive bacteria (Staphylococcus aureus) and has excellent development and application potential.

[0141] Application Example 2

[0142] This embodiment mainly uses 2-phenylcyclohexanone as a raw material to synthesize 2-phenylcyclohexanol.

[0143] In a pressure-resistant reactor, 2-phenylcyclohexanone, a Pd / C catalyst, and ethanol were added, and a hydrogenation reduction reaction was carried out under a hydrogen atmosphere. After the reaction was completed, the catalyst was removed by filtration, and the solvent was removed by rotary evaporation to obtain 2-phenylcyclohexanol.

[0144] .

[0145] 2-Phenylon, used as a chiral aid in the synthesis of Whitesell chiral esters and for asymmetric olefin addition, is an important chiral aid precursor and also has significant application value in chromatographic columns, demonstrating that the α-arylcyclohexanone synthesized in this application has important derivatization application value.

[0146] Summarize:

[0147] This application utilizes readily available and inexpensive aryl diazonium salts and cyclohexene as raw materials to efficiently synthesize various α-arylcyclohexanones in an aqueous mixed solvent under visible light-driven conditions, aided by a Zn₂CuInS₄ / ZnS quantum dot photocatalyst and tert-butyl hypochlorite additive. This method not only expands the application range of the Meerwein reaction but also avoids the use of precious metals, offers mild conditions, and allows for catalyst recycling, aligning with the trend towards green chemistry.

Claims

1. A method for synthesizing an α-aryl cyclohexanone compound, characterized by, The process includes the following steps: using aryldiazotetrafluoroborate and cyclohexene as raw materials, in the presence of additives, in the presence of a mixed solvent, under visible light irradiation, and in the presence of a quantum dot catalyst, α-arylcyclohexanone compounds are obtained by reaction. The additive is tert-butyl hypochlorite; The visible light is blue light with a wavelength of 420-460 nm; The mixed solvent is a mixture of acetonitrile, water and dimethyl sulfoxide; The quantum dot catalyst is Zn2CuInS4 / ZnS QDs, which is prepared by the following method: Cu(NO3)2·3H2O, In(NO3)3·4H2O, thiourea, and mercaptopropionic acid are dissolved in deionized water and mixed; sodium hydroxide is added to the above mixed solution to adjust the pH value of the solution to 10-11, and then the mixture is heated at 100-120℃ for 30-60 min; after cooling to room temperature, Zn(Ac)2·2H2O, thiourea, and mercaptopropionic acid are added to the above solution and sonicated for 1-10 min, and then heated at 100-120℃ for 0.5-2 h. After cooling to room temperature, the mixture is centrifuged, washed, and dried to obtain the quantum dot catalyst Zn2CuInS4 / ZnS QDs.

2. The method for synthesizing an α-arylcyclohexanone compound according to claim 1, characterized in that: In the mixed solvent, the volume ratio of acetonitrile:water:dimethyl sulfoxide is 7:2:

1.

3. The method for synthesizing an α-arylcyclohexanone compound according to claim 1, characterized in that: The amount of the quantum dot catalyst used is 1-5 g / mol relative to aryldiazotetrafluoroborate.

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