Method for photochemically synthesizing benzo [c] cinnoline compound by using azo compound

Abstract

The invention belongs to the technical field of organic synthesis, and particularly relates to a method for photochemically synthesizing a benzo [c] cinnoline compound through an azo compound. The method for photochemically synthesizing the benzo [c] cinnoline compound through the azo compound comprises the following steps that an azobenzene compound, lewis acid and an oxidizing agent are added into an organic solvent and react under the condition of white light irradiation at the temperature of 40-50 DEG C, water quenching is conducted after the reaction is completed, then separation and purification are conducted, and the product benzo [c] cinnoline compound is obtained. The method has the advantages of simple operation, low toxicity of reactants, no need of addition of noble metals, easy separation of products and high yield.

Description

Technical Field

[0001] This invention belongs to the field of nitrogen-containing compound synthesis technology, specifically relating to a method for photochemical synthesis of benzo[c] oxaloline compounds from azo compounds. Background Technology

[0002] Benzo[c] borazene compounds, as an important class of nitrogen-containing fused-ring heterocyclic compounds, can be applied in many fields such as pharmaceutical research and development, optoelectronic materials, and analytical testing, and are one of the research focuses in the fields of fine chemicals and functional molecules.

[0003] In the field of pharmaceutical research and development, benzo[c]cenline compounds are the core pharmacophores for constructing various active drug molecules with antibacterial, antitumor, and anti-inflammatory effects. Compared with traditional monocyclic heterocyclic drugs, their rigid fused-ring structure can significantly improve the binding specificity of drugs to targets, providing key molecular framework support for the development of novel and highly effective drugs and overcoming clinical drug resistance. In the field of optoelectronic materials, these compounds can serve as key functional components and are widely used in the preparation of organic semiconductor devices, fluorescent probes, and solar cells, effectively controlling the electron transport performance, fluorescence quantum yield, and photoelectric conversion efficiency of materials. In the field of analytical detection, benzo[c]cenline derivatives are the core identification unit for the rapid detection of hazardous chemicals such as picric acid, and their specific spectral response characteristics provide important technical support for environmental monitoring, food safety testing, and public safety control.

[0004] Although benzo[c]cenline compounds have broad application prospects, existing synthetic methods still have many technical defects, which seriously restrict their large-scale production and industrial application. At present, the main synthetic routes of benzo[c]cenline include four types of methods: benzidine diazotization cyclization, 2,2'-dinitrobiphenyl reduction cyclization, metal-catalyzed cross-coupling, and azobenzene photochemical cyclization. Among them, the benzidine diazotization cyclization method is simple and mild, but the raw material benzidine is highly carcinogenic, the diazotization process has many side reactions, and the product purity and yield are low, posing significant safety and environmental risks and making it difficult to scale up industrially; the 2,2'-dinitrobiphenyl reduction cyclization method is simple and can be carried out in one pot without the need for diazotization intermediates, but the reduction process is difficult to control precisely, easily generating toxic byproducts, and the reagent cost is high and the amount of waste is large, limiting its industrial application; the metal catalytic cross-coupling method has high selectivity, good product purity, and wide substrate applicability, but it requires pre-modification of the substrate, which is cumbersome. At the same time, the precious metal catalyst is expensive, difficult to recover, and the reaction conditions are harsh, making it difficult to achieve low-cost large-scale production; the azobenzene photochemical cyclization method has readily available raw materials and mild conditions, but it relies on a strongly acidic corrosion system, has low photoreaction efficiency and poor selectivity, produces many byproducts, and has an upper limit on yield, making the ultraviolet photochemical process difficult to adapt to continuous industrial production.

[0005] In summary, existing methods for synthesizing benzo[c]cenline compounds generally suffer from problems such as high toxicity of raw materials, poor selectivity, numerous byproducts, low yields, harsh reaction conditions, severe equipment corrosion, high catalyst costs, insufficient environmental friendliness, and difficulty in large-scale production. Therefore, developing a method for synthesizing benzo[c]cenline compounds that uses inexpensive and readily available raw materials, operates under mild reaction conditions, has simple and efficient steps, high selectivity, and is suitable for large-scale industrial production is of significant practical importance and economic value for overcoming existing technological bottlenecks, reducing production costs, and promoting their practical applications in fields such as medicine, optoelectronic materials, and analytical testing. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a method for the photochemical synthesis of benzo[c]cenline compounds from azo compounds. This method is simple to operate, produces reactants with low toxicity, requires no addition of precious metals, and yields easily separated and high-yield products.

[0007] The method for photochemical synthesis of benzo[c]oxoline compounds from azo compounds according to the present invention includes the following steps: Azobenzene compounds, Lewis acids, and oxidants were added to an organic solvent and reacted at 40-50°C under white light irradiation. After the reaction was completed, the mixture was quenched with water and then separated and purified to obtain the product, benzo[c] oxaloline compounds. The azobenzene compounds are symmetrical azobenzene compounds. or asymmetric azobenzene compounds ; Wherein, substituent R1 is one of 4-hydrogen, 4-dimethyl, 4-di-tert-butyl, and 3,5-dimethyl; substituent R2 is one of 4-methyl, 4-tert-butyl, 4-benzyl, 4-cyclohexyl, 4-fluoro, 4-chloro, 4-bromine, 4-iodine, 4-acetyl, 4-methyl ester, 4-trifluoromethoxy, 4-trifluoromethyl, 4-cyano, 4-(1H-imidazol-1-yl), 4-(1H-1,2,3-triazol-1-yl)methyl, 2-methyl, 2-isopropyl, and 3,5-dimethyl. When azobenzene compounds are symmetrical azobenzene compounds When the product is a benzo[c]cenline compound, it is one of benzo[c]cenline, 2,9-dimethylbenzo[c]cenline, 2,9-di-tert-butylbenzo[c]cenline, and 1,3,8,10-tetramethylbenzo[c]cenline; The structural formulas of the above benzo[c]zoline compounds are as follows: , , , ; When azobenzene compounds are asymmetric azobenzene compounds When the benzo[c]cenline compound is 2-methylbenzo[c]cenline, 2-(tert-butyl)benzo[c]cenline, 2-benzylbenzo[c]cenline, 2-cyclohexylbenzo[c]cenline, 2-fluorobenzo[c]cenline, 2-chlorobenzo[c]cenline, 2-bromobenzo[c]cenline, 2-iodobenzo[c]cenline, 1-(benzo[c]cenline-2-yl)ethyl-1-one, methylbenzo[c]cenline-2-carboxylic acid ester, 2-(trifluoromethoxy)benzo[c]cenline, 2- One of the following: (trifluoromethyl)benzo[c]cenline, benzo[c]cenline-2-onitrile, 2-(1H-imidazol-1-yl)benzo[c]cenline, 2-((1H-1,2,3-triazol-1-yl)methyl)benzo[c]cenline, 4-methylbenzo[c]cenline, 4-isopropylbenzo[c]cenline, 2,4-dimethylbenzo[c]cenline, 3-methylbenzo[c]cenline, 1-methylbenzo[c]cenline, 3-chlorobenzo[c]cenline, and 1-chlorobenzo[c]cenline; The structural formulas of the above benzo[c]zoline compounds are as follows: , , , , , , , , , , , , , , , , , .

[0008] The photochemical synthesis of benzo[c]cenline compounds from azo compounds is shown below: ; or .

[0009] In this invention, the Lewis acid is at least one of aluminum trichloride and aluminum trifluoromethanesulfonate; preferably aluminum trichloride.

[0010] The molar ratio of the Lewis acid to the azobenzene compound is (1-3):1.

[0011] In this invention, the oxidant is at least one of m-chloroperoxybenzoic acid, di-tert-butyl peroxide, manganese dioxide, and 2,2,6,6-tetramethylpiperidine-N-oxy radical (TEMPO); preferably 2,2,6,6-tetramethylpiperidine-N-oxy radical.

[0012] The molar ratio of the oxidant to the azobenzene compound is (1-5):1.

[0013] In this invention, the organic solvent is at least one of ethyl acetate, acetonitrile, hexafluoroisopropanol, and dichloromethane; preferably a mixed solution of hexafluoroisopropanol and dichloromethane; most preferably a mixed solution of hexafluoroisopropanol and dichloromethane in a volume ratio of 1:1.

[0014] The volume molar ratio of the organic solvent to the azobenzene compound is (10-30) L: 1 mol.

[0015] In this invention, the white light irradiation is performed using a white LED lamp; preferably, a 30-watt white LED lamp is used. The reaction is carried out under continuous white light irradiation. The reaction is completed when the azobenzene compounds in the reactants are basically completely consumed by thin-layer chromatography (TLC). Then, the reaction system is quenched with water for separation and purification.

[0016] In this invention, the separation and purification operation is as follows: the quenched reaction solution is sequentially extracted with organic reagents and back-extracted with saturated brine, and then sequentially dried with anhydrous sodium sulfate, purified by vacuum distillation and silica gel column chromatography to obtain pure benzo[c] oxaloline compounds.

[0017] In the above separation and purification operations, the organic reagent used for extraction is preferably one of ethyl acetate, dichloromethane, and petroleum ether; the eluent used for silica gel column chromatography purification is preferably a mixed solution of ethyl acetate and petroleum ether with a volume ratio of 1:10.

[0018] The reaction principle of this invention is explained below. The azobenzene compound used is azobenzene (1a), the Lewis acid is aluminum trichloride (AlCl3), the oxidant is 2,2,6,6-tetramethylpiperidine-N-oxygen radical (TEMPO), and the organic solvent is a 1:1 volume ratio mixture of hexafluoroisopropanol and dichloromethane. The reaction synthesizes benzo[c]benzeneline. The reaction mechanism is as follows: Figure 1 As shown.

[0019] First, trans-azobenzene (1a) is converted to cis-azobenzene (1a) under white light irradiation. AlCl3 undergoes a coordination-catalyzed cyclization reaction with azobenzene, resulting in an intermediate (Int1). This intermediate is then oxidatively dehydrogenated by a 2,2,6,6-tetramethylpiperidine-N-oxygen radical (TEMPO) to restore the aromatic conjugation of the ring system, yielding an aromatic intermediate (Int1). ), intermediate After resonance equilibrium, the target product benzo[c]cenline (2a) was finally obtained.

[0020] The benzo[c]oxoline compounds synthesized in this invention are used to prepare the following derivatives via derivatization reactions: Benzo[c]zoline-5-oxide; Benzo[c]-C-C-5-iodine; Benzo[c]pyrazolo[1,2-a]cenline-4-onium tetrafluoroborate; Trimethyl-1H-benzo[c]pyrazolo[1,2-a]cenline-1,2,3-tricarboxylic acid ester; 2-(4-Chlorophenyl)benzo[c]zoline.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention uses photoexcitation to synthesize benzo[c] oxaloline compounds in one step under white light irradiation using azobenzene compounds as reactants. The raw materials are low-cost, and no photosensitizers or precious metals are required. The entire synthesis process does not require high temperature, high pressure, strong acid or strong alkaline conditions, and no inert gas protection is required. The reaction conditions are mild, the products are easy to separate, and there are few by-products. It has good functional group tolerance and avoids the problems of multi-step synthesis, complex operation, harsh reaction conditions, long preparation cycle and strong reagent toxicity in other synthesis methods. (2) The photochemical synthesis method of benzo[c] oxalool compounds of the present invention is simple to operate, only requires white light excitation to carry out the reaction, and the reaction progress can be controlled by instruments during the reaction process, making it suitable for large-scale industrial production. Attached Figure Description

[0022] Figure 1 This is a reaction mechanism diagram for the synthesis of benzo[c]zoline in Example 1 of the present invention; Figure 2 The 1H NMR spectrum of benzo[c]cenline synthesized in Example 1 of this invention; Figure 3 The carbon spectrum of benzo[c]cenline synthesized in Example 1 of this invention; Figure 4 This is a three-dimensional spatial arrangement diagram of the benzo[c]oxaloline synthesized in Example 1 of the present invention. Detailed Implementation

[0023] The present invention will be further described below with reference to embodiments, but is not limited to the specific embodiments listed herein. Unless otherwise specified, the process methods used in the embodiments are conventional methods in the art. Unless otherwise specified, the raw materials used in the embodiments are commercially available conventional raw materials, or can be prepared using existing technologies.

[0024] In some embodiments, symmetrical azobenzene compounds can be prepared by referring to the synthetic routes described in the prior art: .

[0025] Taking 4,4'-dimethylazobenzene as an example, the preparation method is as follows: Cuprous bromide (0.3 mmol), pyridine (0.9 mmol), and p-toluidine (10 mmol) were added to a 100 mL reaction flask under air atmosphere, along with 40 mL of toluene as a solvent. The reaction mixture was vigorously stirred at 60 °C for 20 hours, and the reaction progress was monitored by thin-layer chromatography. After the reaction was completed, the reaction flask was cooled to room temperature, the reaction system was quenched with water, and diluted with ethyl acetate. The resulting mixture was extracted with ethyl acetate, and the combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45 °C. The residue was purified by silica gel column chromatography using petroleum ether / ethyl acetate (200:1 v / v) as the eluent to obtain the target product (yellow solid). The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (1H and 1C spectra, with deuterated chloroform-d as solvent) to be 4,4'-dimethylazobenzene.

[0026] In some embodiments, asymmetric azobenzene compounds can be prepared by referring to the synthetic routes described in the prior art: .

[0027] (E)-1-(4-benzylphenyl)-2-phenyldiazene For example, the preparation method is as follows: Under air atmosphere, 10 mmol of 4-(benzyl)aniline, 10.5 mmol of nitrosamine, and 60 mL of acetic acid were added to a 100 mL reaction flask. The reaction mixture was stirred vigorously for 12 hours, and the reaction progress was monitored by thin-layer chromatography. After the reaction was completed, the reaction flask was cooled to room temperature, and saturated sodium bicarbonate solution was slowly added to the reaction mixture to adjust it to neutral. The mixture was then diluted with ethyl acetate, and the aqueous phase was extracted with ethyl acetate. The organic phases were combined, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45 °C. The residue was purified by silica gel column chromatography using petroleum ether / ethyl acetate (200:1 v / v) as the eluent to give the target compound as a yellow solid. The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (1H and 1C spectra, with deuterated chloroform-d as solvent) and mass spectrometry analysis to be (E)-1-(4-benzylphenyl)-2-phenyldiazene. Example 1

[0028] This embodiment synthesizes benzo[c]cenline. The method is as follows: Azobenzene, Lewis acid, oxidant, and organic solvent were added sequentially to a 10 ml Shrek tube. The reaction tube was placed in an RLH-18CU 8-well photoluminescence analyzer and irradiated with a white light source (30 watt white LED lamp) under magnetic stirring. The reaction was carried out at the set temperature, and the reaction progress was monitored by thin-layer chromatography (TLC). The reaction was considered complete when the azobenzene compounds were almost completely consumed. The system was quenched with water, extracted with dichloromethane, and the organic phases were combined and washed with saturated brine. After drying with anhydrous sodium sulfate, the mixture was filtered and concentrated under reduced pressure at 38°C. The residue was purified by rapid silica gel column chromatography (eluent was a 1:10 mixture of ethyl acetate and petroleum ether, with a gradient from 1:10 to 1:5, v / v) to obtain the target product benzo[c]cenline, and the product yield was calculated.

[0029] The reactant ratios and reaction conditions are shown in Table 1. The abbreviations for each substance are as follows: hexafluoroisopropanol (HFIP), dichloromethane (CH2Cl2), ethyl acetate (EtOAc), acetonitrile (MeCN), tetrahydrofuran (THF), methanol (MeOH), dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), 2,2,6,6-tetramethylpiperidine-N-oxygen radical (TEMPO), aluminum trichloride (AlCl3), aluminum trifluoromethanesulfonate (Al(OTf)3), zinc trifluoromethanesulfonate (Zn(OTf)2), zinc chloride (ZnCl2), zinc bromide (ZnBr2), zinc iodide (ZnI2), silver hexafluoroantimonate (AgSbF6), m-chloroperoxybenzoic acid (MCPBA), di-tert-butyl peroxide (DTBP), and manganese dioxide (MnO2).

[0030] Table 1. Reaction conditions for the synthesis of benzo[c]zoline In Table 1, numbers 1-8 were used to investigate the types of organic solvents without the addition of oxidants. The results showed that the synthesis reaction proceeded well when the organic solvents were ethyl acetate, acetonitrile, dichloromethane, and hexafluoroisopropanol. The yield of the target product was the best when the organic solvent was a mixture of hexafluoroisopropanol and dichloromethane.

[0031] Numbers 8-14 investigated the types of Lewis acids without the addition of oxidants. The results showed that aluminum trichloride, aluminum trifluoromethanesulfonate, zinc trifluoromethanesulfonate, zinc chloride, zinc bromide, zinc iodide, and silver hexafluoroantimonate, as Lewis acids, could all promote the synthesis reaction. When the Lewis acids were aluminum trichloride and aluminum trifluoromethanesulfonate, the yield of the target product was significantly better than that of other Lewis acids.

[0032] The types of oxidants were investigated in samples 15-18. The results showed that m-chloroperoxybenzoic acid, di-tert-butyl peroxide, manganese dioxide, and 2,2,6,6-tetramethylpiperidine-N-oxy radical (TEMPO) could all promote the synthesis reaction. The yield of the target product was the best when 2,2,6,6-tetramethylpiperidine-N-oxy radical (TEMPO) was used as the oxidant.

[0033] The effects of different amounts of oxidant and Lewis acid on the reaction were investigated in experiments No. 8 and Nos. 18-23. The results showed that the yield of the target product was relatively low when no oxidant was added. The yield of the target product was optimal when the molar ratio of oxidant to azobenzene compound was higher than 2:1 and the molar ratio of Lewis acid to azobenzene compound was higher than 2:1.

[0034] Numbers 24-28 investigated the effects of reaction temperature and organic solvent dosage on the reaction. The results showed that the target products had high yields when the reaction temperature was in the range of 40-50℃ and the volume molar ratio of organic solvent to azobenzene compound was in the range of (10-30) L:1 mol.

[0035] The structure of the above products was confirmed by nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). The NMR spectra were obtained using deuterated chloroform (CDCl3) as the solvent, and the proton NMR spectra were measured separately. 1 H NMR and carbon spectroscopy (H NMR) 13 (C10 NMR) confirmed that it was the target product benzo[c]zoline.

[0036] Hydrogen spectrum (H NMR) 1 H NMR) such as Figure 2 As shown, 1H NMR (400 MHz, CDCl3) δ 8.69 - 8.66 (m, 2H), 8.47 - 8.44 (m, 2H), 7.84 - 7.81 (m, 4H).

[0037] Carbon spectrum (CMR) 13 (C NMR) such as Figure 3 As shown, 13 C NMR (101 MHz, CDCl3) δ 145.29, 131.53, 131.24, 129.22, 121.41, 120.84.

[0038] Simultaneously, X-ray crystallography was performed on the synthesized benzo[c]cenline, as follows: (1) Sample preparation: Take 30 mg of benzo[c] cyclophosphine and dissolve it in a mixed solvent of dichloromethane and petroleum ether (500 μL / 3 ml). The solvent is slowly evaporated at room temperature under normal pressure.

[0039] (2) Crystal Testing: A single crystal of benzo[c]cenline was selected and mounted on a fine glass fiber in an air atmosphere. X-ray diffraction intensity data were collected at 170.0 K using an Agilent SuperNova CCD surface diffractometer equipped with a Cu Kα radiation source (λ=1.54184Å). The raw frame data were converted into SHELX format reflection files by integration using the SAINT program, and Lorentz factor and polarization effect corrections were performed. The absorption effect correction of the incident beam and diffracted beam was performed using the SADABS program. No crystal attenuation was observed during data collection. The crystal structure was analyzed using a combination of direct method and difference Fourier synthesis method, and based on F... 2 Refinement was performed using the full matrix least squares method. In the final refinement cycle, all non-hydrogen atoms were treated with anisotropic displacement parameters.

[0040] The test results are shown in Table 2 and Figure 4 As shown.

[0041] Table 2. Crystallographic test data of benzo[c]cenline Figure 4 The three-dimensional spatial arrangement diagram of molecules obtained from crystal testing is shown in Table 2 and... Figure 4 It can be seen that the product synthesized in this embodiment has the three-dimensional molecular structure of benzo[c]zoline and is a single pure substance. Example 2-24

[0042] Examples 2-24 show the synthesis of a series of benzo[c]oxoline compounds, using the following methods: Add the following to a 10 ml Shrek tube in sequence: an azobenzene compound (0.2 mmol), aluminum trichloride (0.4 mmol), 2,2,6,6-tetramethylpiperidine-N-oxy radical (0.4 mmol), and 4.0 ml of a 1:1 mixture of hexafluoroisopropanol and dichloromethane. Place the reaction tube in an RLH-18CU container. In an 8-well photocatalytic reactor, the reaction was carried out under magnetic stirring and irradiated with a white light source (30-watt white LED lamp) at 45°C. The reaction progress was monitored by thin-layer chromatography (TLC). The reaction was considered complete when the azobenzene compounds were almost completely consumed. The system was quenched with water, extracted with dichloromethane, and the organic phases were combined and washed with saturated brine. After drying with anhydrous sodium sulfate, the mixture was filtered and concentrated under reduced pressure at 38°C. The residue was purified by rapid silica gel column chromatography (eluent was a 1:10 mixture of ethyl acetate and petroleum ether, with a gradient from 1:10 to 1:5, v / v) to obtain the target product, benzo[c]cenline compounds, and the product yield was calculated.

[0043] The azobenzene compounds used in Examples 2-24 and the synthesized benzo[c] oxaloline compounds are shown in Table 3.

[0044] Table 3 Reactants and target products of Examples 2-24 The structures of the products from the above embodiments were confirmed using nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). The NMR spectra were obtained using deuterated chloroform (CDCl3) as the solvent, and the proton NMR spectra were measured. 1 H NMR, carbon spectrum ( 13 C NMR, fluorine spectrum ( 19 F NMR), the results are as follows. Example 2:

[0045] 1 H NMR (400 MHz, CDCl3) δ 8.50 (d, J = 8.3 Hz, 2H), 8.15 (s, 2H), 7.59 (d, J = 8.4 Hz, 2H), 2.59 (s, 6H).

[0046] 13 C NMR (101 MHz, CDCl3) δ 144.23, 141.92, 130.93, 130.82, 120.80, 120.57, 77.36, 22.38.

[0047] HRMS (ESI) m / z: [M+H] + calcd for C 14 H 13 N2 + 209.1074; found 209.1082. Example 3:

[0048] 1 H NMR (400 MHz, CDCl3) δ 8.64 (d, J = 8.8 Hz, 2H), 8.52 (s, 2H), 7.96 (dd, J = 8.7 Hz, J=2.1 Hz 2H), 1.52 (s, 18H).

[0049] 13 C NMR (101 MHz, CDCl3) δ 154.83, 144.35, 130.93, 127.75, 121.03, 116.38, 35.87, 31.40.

[0050] HRMS (ESI) m / z: [M+H] + calcd for C 20 H 25 N2 + 293.2013; found 293.2010. Example 4:

[0051] 1 H NMR (400 MHz, CDCl3) δ 8.27 (s, 2H), 7.50 (s, 2H), 2.59 (d, J =14.2 Hz, 12H).

[0052] 13 C NMR (100 MHz, CDCl3) δ 146.87, 137.95, 135.26, 133.73, 127.34, 119.08, 22.52, 21.29.

[0053] HRMS (ESI) m / z: [M+H] + calcd for C 16 H 17 N2 + 237.1387; found 237.1387. Example 5:

[0054] 1 1H NMR (400 MHz, CDCl3) δ 8.67 - 8.60 (m, 1H), 8.52 (d, J = 8.4 Hz, 1H), 8.44 - 8.38 (m, 1H), 8.17 (s, 1H), 7.84 - 7.75 (m, 2H), 7.60 (d, J = 8.4 Hz, 1H), 2.59 (s, 3H).

[0055] 13 13C NMR (100 MHz, CDCl3) δ 145.29, 144.20, 142.32, 131.53, 131.19, 131.07, 130.94, 129.21, 129.04, 121.38, 120.86, 120.76, 120.57, 29.74, 22.39.

[0056] HRMS (ESI) m / z: [M+H] + calcd for C 13 12H 11 2N + 195.0917; found 195.0907. Example 6:

[0057] 1 1H NMR (400 MHz, CDCl3) δ 8.69 (dd, J = 17.5, 7.3 Hz, 2H), 8.60 (d, J = 9.4 Hz, 1H), 8.51 (s, 1H), 7.97 (d, J = 8.8 Hz, 1H), 7.87 (t, J = 7.0 Hz, 2H), 1.50 (s, 9H).

[0058] 13 13C NMR (101 MHz, CDCl3) δ 154.83, 144.35, 130.93, 127.75, 121.03, 116.38, 35.87, 31.40.

[0059] HRMS (ESI) m / z: [M+H] + calcd for C 16 13H 17 2N + 237.1387; found 237.1387. Example 7:

[0060] 1 1H NMR (400 MHz, CDCl3) δ 8.71 - 8.65 (m, 1H), 8.61 (d, J = 8.4 Hz, 1H), 8.47 - 8.40 (m, 1H), 8.28 (s, 1H), 7.85 - 7.78 (m, 2H), 7.67 (dd, J = 8.5, 1.8 Hz, 1H), 7.37 - 7.29 (m, 2H), 7.30 - 7.20 (m, 3H), 4.25 (s, 2H).

[0061] 13 13C NMR (100 MHz, CDCl3) δ 145.39, 145.25, 144.40, 139.78, 131.38, 131.30, 131.17, 130.74, 129.18, 129.13, 128.84, 126.71, 121.48, 121.04, 120.84, 120.79, 42.53.

[0062] HRMS (ESI) m / z: [M+H] + calcd for C 19 H 15 N2 + 271.1230; found 271.1228. Example 8:

[0063] 1 1H NMR (400 MHz, CDCl3) δ 8.73 - 8.65 (m, 1H), 8.62 (d, J = 8.6 Hz, 1H), 8.58 - 8.50 (m, 1H), 8.31 (s, 1H), 7.89 - 7.77 (m, 2H), 7.73 (dd, J = 8.6 Hz, 2.0 Hz 1H), 2.80 (t, J = 11.9 Hz, 3.4 Hz, 1H), 2.00 (d, J = 13.1 Hz, 2H), 1.91 (d, J = 12.8 Hz, 2H), 1.81 (d, J = 12.7 Hz, 1H), 1.52 (dq, J = 39.4, 12.6 Hz, 4H), 1.33 (tt, J = 12.5 Hz, 1H).

[0064] 13 13C NMR (100 MHz, CDCl3) δ 152.13, 145.41, 144.65, 131.23, 131.21, 131.19, 129.18, 129.03, 121.47, 121.17, 121.04, 118.42, 45.38, 34.44, 26.85, 26.14。

[0065] HRMS (ESI) m / z: [M+H] + calcd for C 18 H 18 N2Na + 285.1363; found 285.1374。 Example 9:

[0066] 1 1H NMR (400 MHz, CDCl3) δ 8.79 - 8.69 (m, 2H), 8.45 - 8.38 (m, 1H), 8.11 (dd, J = 9.3, 2.7 Hz, 1H), 7.97 - 7.85 (m, 2H), 7.61 (td, J = 8.2, 2.7 Hz, 1H)。

[0067] 13 13C NMR(100 MHz, CDCl3) δ 163.90 (d, J = 253.5 Hz), 145.04, 142.85, 134.55, 134.45, 131.68, 131.41, 130.04, 123.16 (d, J C-F = 10.5 Hz), 121.64, 120.62 (d, J C-F = 4.7 Hz), 118.9 (d, J C-F = 24.6 Hz), 106.25 (d, J C-F = 23.1Hz)。

[0068] 19 19F NMR (376 MHz, CDCl3) δ -104.05。

[0069] HRMS (ESI) m / z: [M+H] + calcd for C 12 H8FN2 + 199.0667; found 199.0654。 Example 10:

[0070] 1 H NMR (400 MHz, CDCl3) δ 8.76 - 8.69 (m, 1H), 8.65 (d, J = 8.8 Hz,1H), 8.48 (d, J = 2.4 Hz, 1H), 8.47 - 8.42 (m, 1H), 7.96 - 7.86 (m, 2H), 7.81(dd, J = 8.8, 2.4 Hz, 1H).

[0071] 13 C NMR (100 MHz, CDCl3) δ 145.43, 143.67, 138.08, 133.00, 131.98,131.47, 130.19, 130.06, 122.17, 121.48, 121.15, 119.87.

[0072] HRMS (ESI) m / z: [M+H] + calcd for C 12 H8ClN2 + 215.0371; found 215.0362. Example 11:

[0073] 1 H NMR (400 MHz, CDCl3) δ 8.79 - 8.71 (m, 1H), 8.69 (s, 1H), 8.59 (d,J = 8.7 Hz, 1H), 8.52 - 8.42 (m, 1H), 8.01 - 7.87 (m, 3H).

[0074] 13 C NMR (100 MHz, CDCl3) δ 145.47, 143.86, 133.01, 132.90, 132.06,131.52, 130.09, 126.72, 124.49, 122.42, 121.50, 119.68.

[0075] HRMS (ESI) m / z: [M+H] + calcd for C 12 H8BrN2 + 258.9866; found 258.9851. Example 12:

[0076] 1 H NMR (400 MHz, CDCl3) δ 8.93 (d, J = 1.9 Hz, 1H), 8.77 - 8.70 (m,1H), 8.52 - 8.46 (m, 1H), 8.43 (d, J = 8.7 Hz, 1H), 8.16 (dd, J = 8.7, 1.7Hz, 1H), 7.97 - 7.89 (m, 2H).

[0077] 13 C NMR (100 MHz, CDCl3) δ 145.47, 144.18, 138.39, 132.73, 132.11, 131.53, 131.02, 130.03, 122.49, 121.46, 119.30, 99.38.

[0078] HRMS (ESI) m / z: [M+H] + calcd for C 12 H8IN2 + 306.9727; found 306.9736. Example 13:

[0079] 1 H NMR (400 MHz, CDCl3) δ 9.10 (s, 1H), 8.83 - 8.71 (m, 2H), 8.65 -8.58 (m, 1H), 8.36 (dd, J = 8.6, 1.7 Hz, 1H), 7.99 - 7.89 (m, 2H), 2.81 (s,3H).

[0080] 13 C NMR (100 MHz, CDCl3) δ 197.29, 145.88, 145.80, 138.41, 132.40,131.89, 131.75, 129.98, 128.02, 122.84, 121.51, 120.89, 120.65, 27.22.

[0081] HRMS (ESI) m / z: [M+H] + calcd for C 14 H 11 N2O +223.0866; found 223.0848. Example 14:

[0082] 1 H NMR (400 MHz, CDCl3) δ 9.26 (d, J = 1.8 Hz, 1H), 8.82 - 8.73 (m,2H), 8.68 - 8.61 (m, 1H), 8.46 (dd, J = 8.6, 1.7 Hz, 1H), 8.00 - 7.90 (m,2H), 4.05 (s, 3H).

[0083] 13 C NMR (101 MHz, CDCl3) δ 166.18, 146.08, 145.81, 132.39, 132.32,131.70, 131.65, 129.94, 129.19, 124.52, 121.67, 120.82, 120.55, 52.93.

[0084] HRMS (ESI) m / z: [M+H] + calcd for C 14 H 11 N2O2 + 239.0816; found 239.0804. Example 15:

[0085] 1 H NMR (400 MHz, CDCl3) δ 8.77 (d, J = 9.0 Hz, 1H), 8.75 - 8.69 (m,1H), 8.49 - 8.40 (m, 1H), 8.28 (s, 1H), 7.98 - 7.86 (m, 2H), 7.71 (d, J = 9.0Hz, 1H).

[0086] 13 C NMR (100 MHz, CDCl3) δ 150.87 (q, JC-F = 2.2 Hz) 145.25, 143.34,133.97, 132.01, 131.56, 130.20, 122.53, 122.41, 121.49, 120.56 (q, JC-F =257.9 Hz), 120.31, 112.13.

[0087] 19 19F NMR (376 MHz, CDCl3) δ -57.45。

[0088] HRMS (ESI) m / z: [M+H] + calcd for C 13 H8F3N2O + 265.0584; found 265.0583。 Example 16:

[0089] 1 1H NMR(400 MHz, CDCl3) δ 8.87 (d, J = 8.6 Hz, 1H), 8.84 (s, 1H), 8.84 - 8.75 (m, 2H), 8.63 - 8.55 (m, 1H), 8.08 (dd, J = 8.6, 1.8 Hz, 1H), 8.03 - 7.93 (m, 2H)。

[0090] 13 13C NMR (100 MHz, CDCl3) δ 145.81, 145.47, 133.09 (q, J C-F = 32.5 Hz),132.57, 131.83, 130.34, 125.38 (q, J C-F = 3.3 Hz), 125.11, 122.40, 121.48,120.74, 120.34, 119.80 (q, J C-F = 4.3 Hz)。

[0091] 19 19F NMR (376 MHz, CDCl3) δ -62.45。

[0092] HRMS (ESI) m / z: [M+H] + calcd for C 13 H8F3N2 + 249.0635; found 249.0630。 Example 17:

[0093] 11H NMR (400 MHz, DMSO-d6) δ 9.58 (s, 1H), 9.01 (d, J = 9.6 Hz, 1H), 8.85 (d, J = 8.5 Hz, 1H), 8.77 (d, J = 7.4 Hz, 1H), 8.34 (dd, J = 8.5, 1.6 Hz, 1H), 8.19 - 8.07 (m, 2H).

[0094] 13 13C NMR (100 MHz, DMSO-d6) δ 145.31, 144.33, 133.18, 131.69, 131.31, 130.97, 130.78, 129.54, 122.84, 120.48, 119.13, 118.24, 114.20.

[0095] HRMS (ESI) m / z: [M+H] + calcd for C 13 H7N3Na + 228.0533; found 228.0546. Example 18:

[0096] 1 1H NMR (400 MHz, DMSO-d6) δ 9.10 (d, J = 2.3 Hz, 1H), 9.06 (d, J = 7.6 Hz, 1H), 8.80 (d, J = 8.9 Hz, 1H), 8.72 (s, 1H), 8.69 (d, J = 7.5 Hz, 1H), 8.37 (dd, J = 8.9, 2.3 Hz, 1H), 8.20 (d, J = 1.6 Hz, 1H), 8.13 - 8.01 (m, 2H), 7.25 (s, 1H).

[0097] 13 13C NMR (100 MHz, DMSO-d6) δ 144.90, 143.12, 138.88, 136.29, 132.64, 132.03, 130.61, 130.43, 130.40, 123.07, 122.08, 121.91, 120.20, 118.20, 111.73.

[0098] HRMS (ESI) m / z: [M+H] +calcd for C 15 H 11 N4 + 247.0979; found 247.0979. Example 19:

[0099] 1 H NMR (400 MHz, DMSO-d6) δ 8.84 (s, 1H), 8.82 (s, 1H), 8.78 (d, J =8.5 Hz, 1H), 8.70 - 8.63 (m, 2H), 8.06 (s, 1H), 8.06 - 7.98 (m, 2H), 7.83 (d,J = 8.6 Hz, 1H), 5.80 (s, 2H).

[0100] 13 C NMR(101 MHz, DMSO-d6) δ 152.06, 144.83, 144.76, 144.12, 140.20,132.24, 130.97, 130.51, 130.02, 129.30, 122.15, 121.57, 120.21, 119.99, 52.09.

[0101] HRMS (ESI) m / z: [M+H] + calcd for C 15 H 12 N5 + 262.1088; found 262.1084. Example 20:

[0102] 1 H NMR (400 MHz, CDCl3) δ 8.72 (dd, J = 6.9, 2.7 Hz, 1H), 8.58 - 8.51(m, 1H), 8.39 (d, J = 10.5 Hz, 1H), 7.91 - 7.82 (m, 2H), 7.76 (d, J = 8.0 Hz, 1H), 7.68 (d, J = 7.2 Hz, 1H), 3.16 (s, 3H).

[0103] 13C NMR (101 MHz, CDCl3) δ 145.21, 144.12, 140.02, 131.54, 131.36,131.33, 130.12, 129.12, 121.71, 121.23, 120.94, 119.28, 18.25.

[0104] HRMS (ESI) m / z: [M+H] + calcd for C 13 H 11 N2 + 195.0917; found 195.0910. Example 21:

[0105] 1 H NMR (400 MHz, CDCl3) δ 8.77 - 8.69 (m, 1H), 8.61 - 8.53 (m, 1H), 8.42 (d, J = 8.2 Hz, 1H), 7.91 - 7.83 (m, 3H), 7.79 (d, J = 7.4 Hz, 1H), 4.92 (p, J = 6.9 Hz, 1H), 1.52 (d, J = 7.0 Hz, 6H).

[0106] 13 C NMR (100 MHz, CDCl3) δ 150.05, 145.06, 142.85, 131.83, 131.28,131.23, 129.06, 125.65, 121.74, 121.39, 120.85, 118.96, 27.55, 24.00.

[0107] HRMS (ESI) m / z: [M+H] + calcd for C 15 H 15 N2 + 223.1230; found 223.1232. Example 22:

[0108] 1H NMR (400 MHz, CDCl3) δ 8.69 (td, J = 9.6, 4.0 Hz, 2H), 8.36 (s,1H), 7.84 - 7.77 (m, 2H), 7.46 (s, 1H), 2.98 (s, 3H), 2.57 (s, 3H).

[0109] 13 C NMR (100 MHz, CDCl 3) δ 146.99, 145.95, 138.80, 136.70, 134.53,131.80, 130.88, 129.66, 127.93, 125.20, 122.29, 117.85, 25.68, 21.30.

[0110] HRMS (ESI) m / z: [M+H] + calcd for C 14 H 13 N2 + 209.1074; found 209.1074. Example 23

[0111] In this embodiment, the derivative benzo[c]cenline-5-oxide was synthesized. The method is as follows: In a 25 mL round-bottom flask, benzo[c]oxoline (0.5 mmol), m-chloroperoxybenzoic acid (1.0 mmol), and dichloromethane (5 mL) were added. The reaction mixture was stirred continuously at room temperature under air for 4 hours. The reaction progress was monitored by thin-layer chromatography (TLC). After the reaction was complete, the reaction mixture was diluted with dichloromethane, and the aqueous phase was extracted with dichloromethane. The organic phases were combined, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography using petroleum ether / ethyl acetate (v / v) as the eluent to give a yellow solid product with a yield of 75%. The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (H1N and C1N spectra, with deuterated dimethyl sulfoxide-d6 as solvent) and high-resolution mass spectrometry.

[0112] 1H NMR (400 MHz, DMSO-d6)δ 8.90 (d, J = 8.2 Hz, 1H), 8.74 (d, J = 8.0Hz, 1H), 8.68 (d, J = 8.6 Hz, 1H), 8.10 (t, J = 7.6 Hz, 1H), 8.01 - 7.92 (m,2H), 7.87 (t, J = 7.6 Hz, 1H), 7.81 (t, J = 7.6 Hz, 1H).

[0113] 13 C NMR (100 MHz, DMSO-d6) δ 141.75, 136.70, 133.10, 130.81, 130.56, 129.00, 128.29, 125.44, 123.49, 122.31, 121.36, 117.89.

[0114] HRMS (ESI) m / z: [M+H] + calcd for C 12 H9N2O + 197.0710; found 197.0708. Example 24

[0115] In this embodiment, the derivative benzo[c]cenline-5-iodine was synthesized. The method is as follows: In a 25 mL round-bottom flask, benzo[c]cenline (0.2 mmol), iodomethane (0.4 mmol), and acetonitrile (2 mL) were added. The reaction mixture was stirred continuously at 80 °C in air for 4 hours. The reaction progress was monitored by thin-layer chromatography. After the reaction was completed, the reaction mixture was concentrated under reduced pressure. The residue was washed with n-hexane to give a red solid product with a yield of 85%. The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (H1N and C1N spectra, using deuterated methanol-d4 as solvent) and high-resolution mass spectrometry.

[0116] 1 H NMR (400 MHz, MeOD) δ 9.32 (d, J = 8.7 Hz, 1H), 9.24 (d, J = 8.5Hz, 1H), 8.97 (d, J = 8.6 Hz, 1H), 8.85 (d, J = 8.5 Hz, 1H), 8.60 - 8.53 (m,1H), 8.49 - 8.34 (m,3H).

[0117] 13C NMR (100 MHz, MeOD) δ 144.82, 140.96, 139.20, 136.42, 135.26, 134.35, 133.56, 130.16, 128.11, 125.55, 124.09, 121.94, 53.18.

[0118] HRMS(ESI) m / z: [M+H] + calcd for C 13 H 11 N2Na + 344.9860; found 344.9889. Example 25

[0119] In this embodiment, the derivative benzo[c]pyrazolo[1,2-a]cenline-4-onium tetrafluoroborate was synthesized. The method is as follows: (1) In a 25 ml round-bottom flask, add benzo[c]oxoline (0.4 mmol), 1,3-dibromopropane (2 mmol) and ethanol (2 ml). Stir the reaction mixture continuously at 80 °C in air for 24 hours. Monitor the reaction progress by thin-layer chromatography. After the reaction is complete, cool to room temperature and filter the mixture to obtain a red solid intermediate with a yield of 70%. (2) The red solid (84 mg, 0.28 mmol) obtained in the above steps was placed in a 25 ml round-bottom flask, and chloroform (2 ml) and N-bromosuccinimide (64 mg, 0.36 mmol) were added. The mixture was reacted at 50 °C for 3 hours, and then sodium tetrafluoroborate (153.7 mg, 1.4 mmol) was added. The mixture was stirred at room temperature for 10 hours to allow complete anion exchange. After the reaction was completed, methanol (10 ml) was added to the system. The mixture was filtered through a diatomaceous earth filter, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluted with a gradient of dichloromethane / methanol (volume ratio 50:1 → 10:1) to obtain a white solid product (68.5 mg), with a yield of 80%. The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (H1N and C1N spectra, with deuterated dimethyl sulfoxide-d6 as solvent) and high-resolution mass spectrometry.

[0120] 1H NMR(400 MHz, DMSO-d6): δ 10.03 (d, J = 3.2 Hz, 2H), 8.72 (d, J =8.0 Hz, 2H), 8.60 (d, J = 8.3 Hz, 2H), 7.87 (t, J = 7.7 Hz, 2H), 7.81 (t, J =7.6 Hz, 2H), 7.74 (t, J = 3.2 Hz, 1H).

[0121] 13 C NMR (100 MHz, DMSO-d6): δ 130.99, 130.15, 129.55, 129.14, 124.36, 118.85, 116.69, 110.57.

[0122] HRMS(ESI) m / z: [M+H] + calcd for C 15 H 12 BF4N2 + 307.1025; found 307.1036. Example 26

[0123] In this embodiment, the derivative trimethyl-1H-benzo[c]pyrazolo[1,2-a]cenline-1,2,3-tricarboxylic acid ester was synthesized. The method is as follows: In a 50 mL round-bottom flask, benzo[c]cenline (0.2 mmol), acetonitrile (2 mL), dimethylacetylenic dicarboxylic acid ester (0.6 mmol), and water (2 mL) were added sequentially. The reaction mixture was stirred continuously at room temperature under air atmosphere for 24 hours. The reaction progress was monitored by thin-layer chromatography. After the reaction was completed, the reaction system was quenched with water and extracted with ethyl acetate. The combined organic phases were washed sequentially with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45 °C. The residue was purified by rapid silica gel column chromatography using ethyl acetate-petroleum ether (v / v) as the eluent to give a yellow solid product in 75% yield. The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (H1N and C1N spectra, with deuterated chloroform-d as solvent) and high-resolution mass spectrometry.

[0124] 1H NMR (400 MHz, CDCl3) δ 7.62 - 7.48 (m, 2H), 7.30 - 7.21 (m, 1H), 7.19 - 7.10 (m, 2H), 7.09 - 7.00 (m, 2H), 6.95 - 6.84 (m, 1H), 5.53 (s, 1H), 3.97 (s, 3H), 3.81 (s, 3H), 3.73 (s, 3H).

[0125] 13 C NMR (100 MHz, CDCl3) δ 169.48, 162.86, 161.15, 147.01, 140.49,135.53, 129.83, 128.91, 126.34, 125.88, 123.84, 123.45, 123.37, 121.86,116.30, 110.47, 97.56, 67.61, 53.88, 53.10, 51.65.

[0126] HRMS(ESI) m / z: [M+H] + calcd for C 21 H 19 N2O6 + 395.1238; found .395.1230. Example 27

[0127] In this embodiment, the derivative 2-(4-chlorophenyl)benzo[c]zoline was synthesized. The method is as follows: In a 50 mL round-bottom flask, 0.4 mmol of 2-bromobenzo[c]cenline, 0.44 mmol of (4-chlorophenyl)boronic acid, 0.02 mmol of tetra(triphenylphosphine)palladium, and 1.6 mmol of potassium carbonate were added sequentially. The reaction mixture was stirred continuously at 100 °C for 16 hours, and the reaction progress was monitored by thin-layer chromatography. After the reaction was completed, the reaction system was cooled to room temperature, diluted with dichloromethane, and the aqueous phase was extracted with dichloromethane. The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 38 °C. The residue was purified by rapid silica gel column chromatography using ethyl acetate-petroleum ether (v / v 1:10) as the eluent to give a yellow solid product in 88% yield. The structure of the product was confirmed by nuclear magnetic resonance spectroscopy (H1N and C1N spectra, with deuterated chloroform-d as solvent) and mass spectrometry.

[0128] 1H NMR (400 MHz, CDCl3) δ 8.69 (dd, J = 9.1, 6.2 Hz, 2H), 8.56 (s,1H), 8.55 - 8.49 (m, 1H), 7.98 (dd, J = 8.5, 1.9 Hz, 1H), 7.86 (dt, J = 6.2,3.4 Hz, 2H), 7.65 (d, J = 8.5 Hz, 2H), 7.47 (d, J = 8.5 Hz, 2H)。

[0129] 13 C NMR (100 MHz, CDCl3) δ 145.53, 144.49, 142.96, 138.34, 134.94,131.84, 131.65, 131.36, 129.50, 129.40, 129.05, 128.44, 121.39, 121.25,120.86, 119.29。

[0130] HRMS(ESI) m / z: [M+H] + calcd for C 18 H 12 ClN2 + 219.0684; found 219.0684。

Claims

1. A method for photochemical synthesis of benzo[c]cenline compounds from azo compounds, characterized in that: Includes the following steps: Azobenzene compounds, Lewis acids, and oxidants were added to an organic solvent and reacted at 40-50°C under white light irradiation. After the reaction was completed, the mixture was quenched with water and then separated and purified to obtain the product, benzo[c] oxaloline compounds. The azobenzene compounds are symmetrical azobenzene compounds. or asymmetric azobenzene compounds ; Wherein, substituent R1 is one of 4-hydrogen, 4-dimethyl, 4-di-tert-butyl, and 3,5-dimethyl; substituent R2 is one of 4-methyl, 4-tert-butyl, 4-benzyl, 4-cyclohexyl, 4-fluoro, 4-chloro, 4-bromine, 4-iodine, 4-acetyl, 4-methyl ester, 4-trifluoromethoxy, 4-trifluoromethyl, 4-cyano, 4-(1H-imidazol-1-yl), 4-(1H-1,2,3-triazol-1-yl)methyl, 2-methyl, 2-isopropyl, and 3,5-dimethyl. When azobenzene compounds are symmetrical azobenzene compounds When the product is a benzo[c]cenline compound, it is one of benzo[c]cenline, 2,9-dimethylbenzo[c]cenline, 2,9-di-tert-butylbenzo[c]cenline, and 1,3,8,10-tetramethylbenzo[c]cenline; When azobenzene compounds are asymmetric azobenzene compounds When the benzo[c]cenline compound is 2-methylbenzo[c]cenline, 2-(tert-butyl)benzo[c]cenline, 2-benzylbenzo[c]cenline, 2-cyclohexylbenzo[c]cenline, 2-fluorobenzo[c]cenline, 2-chlorobenzo[c]cenline, 2-bromobenzo[c]cenline, 2-iodobenzo[c]cenline, 1-(benzo[c]cenline-2-yl)ethyl-1-one, methylbenzo[c]cenline-2-carboxylic acid ester, 2-(trifluoromethoxy)benzo[c]cenline, 2- One of the following: (trifluoromethyl)benzo[c]cenline, benzo[c]cenline-2-onitrile, 2-(1H-imidazol-1-yl)benzo[c]cenline, 2-((1H-1,2,3-triazol-1-yl)methyl)benzo[c]cenline, 4-methylbenzo[c]cenline, 4-isopropylbenzo[c]cenline, 2,4-dimethylbenzo[c]cenline, 3-methylbenzo[c]cenline, 1-methylbenzo[c]cenline, 3-chlorobenzo[c]cenline, and 1-chlorobenzo[c]cenline.

2. The method for photochemical synthesis of benzo[c]cenline compounds from azo compounds according to claim 1, characterized in that: The Lewis acid is at least one of aluminum trichloride and aluminum trifluoromethanesulfonate.

3. The method for photochemical synthesis of benzo[c]zoline compounds from azo compounds according to claim 1, characterized in that: The molar ratio of the Lewis acid to the azobenzene compound is (1-3):

1.

4. The method for photochemical synthesis of benzo[c]cenline compounds from azo compounds according to claim 1, characterized in that: The oxidant is at least one of m-chloroperoxybenzoic acid, di-tert-butyl peroxide, manganese dioxide, and 2,2,6,6-tetramethylpiperidine-N-oxy free radical.

5. The method for photochemical synthesis of benzo[c]zoline compounds from azo compounds according to claim 1, characterized in that: The molar ratio of the oxidant to the azobenzene compound is (1-5):

1.

6. The method for photochemical synthesis of benzo[c]cenline compounds from azo compounds according to claim 1, characterized in that: The organic solvent is at least one of ethyl acetate, acetonitrile, hexafluoroisopropanol, and dichloromethane.

7. The method for photochemical synthesis of benzo[c]cenline compounds from azo compounds according to claim 1, characterized in that: The volume molar ratio of the organic solvent to the azobenzene compound is (10-30) L: 1 mol.

8. The method for photochemical synthesis of benzo[c]cenline compounds from azo compounds according to claim 1, characterized in that: The white light illumination is performed using white LED lights.

9. The method for photochemical synthesis of benzo[c]zoline compounds from azo compounds according to claim 1, characterized in that: The separation and purification operation is as follows: the quenched reaction solution is sequentially extracted with organic reagents and back-extracted with saturated brine, and then sequentially dried with anhydrous sodium sulfate, vacuum distilled, and purified by silica gel column chromatography to obtain pure benzo[c] oxaloline compounds.

10. The method for photochemical synthesis of benzo[c]cenline compounds from azo compounds according to claim 1, characterized in that: The product, a benzo[c]cenline compound, is used to prepare the following derivatives via derivatization: Benzo[c]zoline-5-oxide; Benzo[c]-C-C-5-iodine; Benzo[c]pyrazolo[1,2-a]cenline-4-onium tetrafluoroborate; Trimethyl-1H-benzo[c]pyrazolo[1,2-a]cenline-1,2,3-tricarboxylic acid ester; 2-(4-Chlorophenyl)benzo[c]zoline.

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