A polycarbonyl carbazole derivative and its preparation method

Abstract

The present invention discloses a multi-carbonyl carbazole derivative and a preparation method thereof, belonging to the technical field of organic synthesis. Using simple indole derivatives, β-chloroketone derivatives and γ-chloroketone derivatives as raw materials, palladium salts as catalysts, adding an oxidant and an additive 2,2,6,6-tetramethylpiperidine N-oxide, and carrying out a Domino indolyl enylation-Diels-Alder cycloaddition-dehydrogenation aromatization-C-H oxidation reaction under alkaline conditions by heating to synthesize the multi-carbonyl carbazole derivative. Compared with the reported synthesis methods of carbazole derivatives, the raw materials of the present invention are easily available, the synthesis reaction conditions are mild, the steps are simple, the product yield is high and the applicable range is wide.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic synthesis, and discloses a polycarbonyl carbazole derivative and a preparation method thereof. Background Art

[0002] Carbazole and its derivatives are an important class of nitrogen-containing heterocyclic compounds, which play important roles in both chemistry and biology. Many molecules containing the carbazole motif have considerable pharmacological activities, such as antiviral, antimalarial, antiestrogenic and antitumor properties (Chem. Lett., 2000, 10, 1021). In addition, carbazole is widely used in various organic optoelectronic materials and chromophores due to its structural rigidity and extensive π-conjugation (Tetrahedron Lett., 2016, 57, 243). Therefore, the synthesis of carbazole derivatives has been widely concerned by chemists.

[0003] At present, a variety of synthetic strategies have been applied to the preparation of carbazole derivatives in the literature. Early methods included reactions such as the Graebe-Ullmann reaction, the Borsche-Drechsel cyclization and the Fischer-Borsche carbazole synthesis. Such methods have harsh reaction conditions and long reaction steps. In recent years, noble metal and transition metal catalysts have been applied to the synthesis of carbazole and its derivatives, enriching the synthetic means of carbazole. One type of method is to construct a nitrogen heterocycle from biphenyl derivatives. However, this type of method requires pre-functionalization and the product structure is limited. Another type of method is to construct a carbazole ring from indole derivatives through a cyclization reaction. This is one of the ways to quickly and effectively obtain carbazole derivatives with diverse structures. Among them, the construction of carbazole by indole cyclization reaction can adopt the following several strategies: [2+2'+2'] cyclization reaction (Org. Chem. 2009, 74, 7481), [2+2'+2"] cyclization reaction (Org. Lett. 2016, 18, 5384) and [4+2] cycloaddition reaction (Adv. Synth. Catal. 2014, 557). Such methods do not require functionalization, have good atom economy and diverse product structures. However, there are few reports on the preparation method for synthesizing polycarbonyl carbazole derivatives by a one-pot reaction. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides a polycarbonyl carbazole derivative and a preparation method thereof. A series of polycarbonyl carbazole derivatives 1 are synthesized by a Domino indolyl enylation-Diels-Alder cycloaddition-dehydrogenation aromatization-C-H oxidation reaction using simple indole derivatives and easily prepared β-chloroketone derivatives and γ-chloroketone derivatives with diverse structures. Compared with the reported synthesis methods of carbazole derivatives, the raw materials of the present invention are easily available, the operation is simple, and the applicable range is wide.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A polycarbonyl carbazole derivative, and the structural formula of the polycarbonyl carbazole derivative 1 is as follows:

[0007]

[0008] Wherein, R 1 is methyl, ethyl, benzyl or allyl; R 2 is H, methyl, methoxy, cyano, nitro, fluorine, chlorine or ester group; R 3 is aryl or an alkyl group with 1-5 carbon atoms, and R 4 is aryl or an alkyl group with 1-5 carbon atoms, and the aryl is phenyl or heteroaryl substituted by methyl, methoxy, fluorine, chlorine, cyano or ester group.

[0009] A preparation method of a polycarbonyl carbazole derivative, and the synthesis route is shown in the following reaction formula (1):

[0010]

[0011] The described preparation method uses the simple and structurally diverse indole derivative 2, the easily prepared and structurally diverse β-chloroketone derivative 3 and γ-chloroketone derivative 4 as raw materials, a palladium salt as a catalyst, adds them to a reaction solvent, and adds an oxidant and an additive. Under alkaline conditions, heating is carried out for the Domino indolyl enylation-Diels-Alder cycloaddition-dehydrogenation aromatization-C-H oxidation reaction of indole derivative 2 with β-chloroketone derivative 3 and γ-chloroketone derivative 4 (Reaction Formula 1), wherein the reaction temperature is 30-150 °C, the reaction time is 1-30 hours. After the reaction is completed, the product is separated and characterized by conventional separation and purification methods to synthesize the polycarbonyl carbazole derivative 1. The molar ratio of the indole derivative 2 to the catalyst is 1:0.05 - 1:0.15, the molar ratio of the indole derivative 2 to the oxidant is 1:1 - 1:8, the molar ratio of the indole derivative 2 to the additive is 1:1 - 1:8, the molar ratio of the indole derivative 2 to the base is 1:1 - 1:8, and the molar ratio of the indole derivative 2, β-chloroketone derivative 3, and γ-chloroketone derivative 4 is 1:1:1 - 1:1:6.

[0012] The structural formula of the described indole derivative 2 is Its substituents are: R 1 is methyl, ethyl, benzyl or allyl; R 2 is H, methyl, methoxy, cyano, nitro, fluorine, chlorine or ester group.

[0013] The structural formula of the described β-chloroketone derivative 3 is Its substituent R 3is an aryl group or an alkyl group having 1 to 5 carbon atoms, and the aryl group is a phenyl group or a heteroaryl group substituted with methyl, methoxy, fluorine, chlorine, cyano or ester group.

[0014] The structural formula of the γ-chloroketone derivative 4 is Its substituent R 4 is an aryl group or an alkyl group having 1 to 5 carbon atoms, and the aryl group is a phenyl group or a heteroaryl group substituted with methyl, methoxy, fluorine, chlorine, cyano or ester group.

[0015] Furthermore, the catalyst is palladium acetate, palladium chloride, tetrakis(triphenylphosphine)palladium or diphenylphosphine dichloride. Preferably, it is palladium acetate, and its catalytic effect is the best. The optimal molar ratio of the indole derivative 2 to palladium acetate is 1:0.05 - 1:0.1.

[0016] Furthermore, the oxidant is copper acetate, copper acetate hydrate, copper chloride hydrate, copper trifluoromethanesulfonate, cuprous chloride. Among them, copper acetate hydrate as the oxidant has the best effect, and the optimal molar ratio of the indole derivative 2 to copper acetate hydrate is 1:2 - 1:5.

[0017] Furthermore, the additive is 2,2,6,6-tetramethylpiperidine 1-oxyl TEMPO. Among them, the optimal molar ratio of the indole derivative 2 to 2,2,6,6-tetramethylpiperidine 1-oxyl is 1:2 - 1:5.

[0018] Furthermore, the base is lithium acetate, sodium acetate, cesium acetate, sodium carbonate or potassium phosphate. Among them, sodium acetate as the base has the best effect, and the optimal molar ratio of the indole derivative 2 to sodium acetate is 1:4 - 1:5.

[0019] Furthermore, the reaction solvent is one or more of ethanol, tetrahydrofuran, toluene, chlorobenzene, acetonitrile and N,N-dimethylformamide. Among them, the reaction carried out in a mixed solvent of N,N-dimethylformamide and toluene has the best effect, and the optimal volume ratio of the two is 1:2 - 1:5.

[0020] Furthermore, the molar ratio of the indole derivative 2 to the β-chloroketone derivative 3 and the γ-chloroketone derivative 4 is preferably 1:1:3 - 1:1:4, and the reaction effect is the best.

[0021] Furthermore, the reaction temperature is preferably 70 - 130 °C, and the reaction time is 12 - 24 hours.

[0022] The reaction mechanism of the present invention is as follows: First, the indole derivative 2 reacts with the enone formed by dehydrochlorination of the β-chloroketone derivative 3 to form an enylindole intermediate, and then the intermediate reacts with the γ-chloroketone derivative 4 through a DA reaction / dehydrogenative aromatization / carbon-hydroxylation to finally synthesize the carbazole derivative 1.

[0023] The present invention provides a method for synthesizing polycarbonyl carbazole derivatives, which has easily available raw materials, mild reaction conditions, wide adaptability, and can be synthesized simply and conveniently. Compared with the prior art, it has the following beneficial effects:

[0024] 1) The reaction raw materials indole derivatives 2, β-chloroketone derivatives 3, and γ-chloroketone derivatives 4 have structural diversity and can be used to synthesize polycarbonyl carbazole derivatives 1 of different types and structures.

[0025] 2) The reaction raw materials 2, 3, and 4 are cheap and easily available. Some raw materials are commercially available, and other raw materials can be prepared by simple methods.

[0026] 3) The synthesis reaction of polycarbonyl carbazole derivatives 1 has mild conditions, simple steps, high product yield, and wide application range.

[0027] In summary, the present invention utilizes the diversity of the types and structures of indole derivatives 2, β-chloroketone derivatives 3, and γ-chloroketone derivatives 4 to efficiently synthesize polycarbonyl carbazole derivatives 1 of different types and structures. The raw materials are cheap and easily available, the operation is simple, and the yield of the target product is high. Description of the Drawings

[0028] Figure 1 It is the 1H NMR spectrum of 1a.

[0029] Figure 2 It is the 13C NMR spectrum of 1a.

[0030] Figure 3 It is the 1H NMR spectrum of 1b.

[0031] Figure 4 It is the 13C NMR spectrum of 1b.

[0032] Figure 5 It is the 1H NMR spectrum of 1d.

[0033] Figure 6 It is the 13C NMR spectrum of 1d.

[0034] Figure 7 It is the 1H NMR spectrum of 1f.

[0035] Figure 8 It is the 13C NMR spectrum of 1f. Detailed Embodiments

[0036] The following further illustrates the present invention with specific embodiments.

[0037] The present invention uses a simple indole derivative 2 as a raw material, and undergoes a Domino indolyl enylation-Diels-Alder cycloaddition-dehydrogenative aromatization-C-H oxidation reaction with β-chloroketone derivatives 3 and γ-chloroketone derivatives 4 under alkaline conditions and heating to synthesize polycarbonyl carbazole derivatives 1. The following examples are helpful for further understanding the present invention, but the content of the present invention is not limited thereto.

[0038] Example 1

[0039]

[0040] In a 35 ml pressure-resistant bottle, under air, palladium acetate Pd(OAc)2 (4.5 mg, 0.02 mmol), 1-methylindole 2a (0.2 mmol), chloropropiophenone 3a (0.2 mmol), chlorobutyrophenone 4a (0.6 mmol), copper acetate monohydrate Cu(OAc)2·H2O (80 mg, 0.4 mmol), sodium acetate NaOAc (0.8 mmol, 67 mg), 2,2,6,6-tetramethylpiperidine 1-oxyl TEMPO (0.4 mmol, 63 mg) and 3 ml of a mixed solvent of N,N-dimethylformamide and chlorobenzene were successively added, and stirred at 120 °C for 12 hours. After cooling to room temperature, it was separated by silica gel column chromatography (the eluent was petroleum ether / ethyl acetate, v / v = 50:1), and then recrystallized to obtain a pale yellow solid product 1a (54 mg, yield 65%). The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0041] Example 2

[0042] The reaction steps and operations were the same as those in Example 1. The difference from Example 1 was that the catalyst was palladium chloride PdCl2 and the molar ratio of indole derivative 2a to palladium chloride PdCl2 was 1:0.05. The reaction was stopped, and the target product 1a (29 mg, yield 35%) was obtained after post-treatment.

[0043] Example 3

[0044] The reaction steps and operations were the same as those in Example 1. The difference from Example 1 was that the catalyst was tetrakis(triphenylphosphine)palladium Pd[P(C6H5)3]4 and the molar ratio of indole derivative 2a to the catalyst was 1:0.15. The reaction was stopped, and the target product 1a (42 mg, yield 50%) was obtained after post-treatment.

[0045] Example 4

[0046] The reaction steps and operations were the same as those in Example 1. The difference from Example 1 was that the oxidant was copper(I) chloride CuCl and the molar ratio of indole derivative 2a to copper(I) chloride CuCl was 1:1. The reaction was stopped, and the target product 1a (32 mg, yield 38%) was obtained after post-treatment.

[0047] Example 5

[0048] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the oxidant is copper trifluoromethanesulfonate Cu(OTf)₂, and the molar ratio of indole derivative 2a to the oxidant copper trifluoromethanesulfonate Cu(OTf)₂ is 1:8. The reaction was stopped, and the target product 1a (40 mg, yield 48%) was obtained after post-treatment.

[0049] Example 6

[0050] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the molar ratio of indole derivative 2 to the additive 2,2,6,6-tetramethylpiperidine 1-oxyl TEMPO is 1:1. The reaction was stopped, and the target product 1a (41 mg, yield 50%) was obtained after post-treatment.

[0051] Example 7

[0052] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the molar ratio of indole derivative 2 to the additive 2,2,6,6-tetramethylpiperidine 1-oxyl TEMPO is 1:8. The reaction was stopped, and the target product 1a (55 mg, yield 66%) was obtained after post-treatment.

[0053] Example 8

[0054] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the base is sodium carbonate Na₂CO₃, and the molar ratio of indole derivative 2a to the base sodium carbonate Na₂CO₃ is 1:1. The reaction was stopped, and the target product 1a (30 mg, yield 35%) was obtained after post-treatment.

[0055] Example 9

[0056] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the base is potassium phosphate K₃PO₄, and the molar ratio of indole derivative 2a to the base potassium phosphate K₃PO₄ is 1:8. The reaction was stopped, and the target product 1a (33 mg, yield 40%) was obtained after post-treatment.

[0057] Example 10

[0058] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the reaction solvent is a mixed solvent of N,N-dimethylformamide and tetrahydrofuran, and the ratio is 1:5. The reaction was stopped, and the target product 1a (25 mg, yield 30%) was obtained after post-treatment.

[0059] Example 11

[0060] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the reaction solvent is a mixed solvent of N,N-dimethylformamide and toluene, and the ratio is 1:2. The reaction was stopped, and after post-treatment, the target product 1a (63 mg, yield 75%) was obtained. It shows that using a mixed solvent of N,N-dimethylformamide and toluene as the reaction solvent is helpful for the reaction to proceed.

[0061] Example 12

[0062] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the reaction solvent is N,N-dimethylformamide. The reaction was stopped, and after post-treatment, the target product 1a (23 mg, yield 28%) was obtained.

[0063] Example 13

[0064] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the reaction temperature is 30 °C and the reaction time is 1 h. The reaction was stopped, and after post-treatment, the target product 1a (23 mg, yield 28%) was obtained.

[0065] Example 14

[0066] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the reaction temperature is 90 °C and the reaction time is 15 h. The reaction was stopped, and after post-treatment, the target product 1a (25 mg, yield 30%) was obtained.

[0067] Example 15

[0068] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the reaction temperature is 150 °C and the reaction time is 30 h. The reaction was stopped, and after post-treatment, the target product 1a (54 mg, yield 65%) was obtained.

[0069] Example 16

[0070]

[0071] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that indole derivative 2b (31 mg, 0.2 mmol) and chlorobenzoylbutanone 4a (36.5 mg, 0.2 mmol) were added to the reaction system, and the molar ratio of 2b, 3a and 4a is 1:1:1. The reaction was stopped, and after post-treatment, an orange-yellow solid 1b (18 mg, 20%) was obtained. The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0072] Example 17

[0073]

[0074] The reaction steps and operations were the same as in Example 1. The difference from Example 1 was that indole derivative 2c (32 mg, 0.2 mmol) and chlorobenzoyl butanone 4a (219 mg, 1.2 mmol) were added to the reaction system, and the molar ratio of 2c, 3a, and 4a was 1:1:6. The reaction was stopped, and after post-treatment, a pale yellow solid 1c (45 mg, 50%) was obtained. The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0075] Example 18

[0076]

[0077] The reaction steps and operations were the same as in Example 1. The difference from Example 1 was that β-chloroketone derivative 3b (40 mg, 0.2 mmol) was added to the reaction system. The reaction was stopped, and after post-treatment, a pale yellow solid 1d (45 mg, 50%) was obtained. The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0078] Example 19

[0079]

[0080] The reaction steps and operations were the same as in Example 1. The difference from Example 1 was that β-chloroketone derivative 3c (36 mg, 0.2 mmol) was added to the reaction system. The reaction was stopped, and after post-treatment, a pale yellow solid 1e (39 mg, 45%) was obtained. The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0081] Example 20

[0082]

[0083] The reaction steps and operations were the same as in Example 1. The difference from Example 1 was that γ-chloroketone derivative 4b (120 mg, 0.6 mmol) was added to the reaction system. The reaction was stopped, and after post-treatment, a pale yellow solid 1f (18 mg, 21%) was obtained. The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0084] Example 21

[0085]

[0086] The reaction steps and operations were the same as in Example 1. The difference from Example 1 was that γ-chloroketone derivative 4c (129 mg, 0.6 mmol) was added to the reaction system. The reaction was stopped, and after post-treatment, a pale yellow solid 1g (47 mg, 53%) was obtained. The target product was confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

[0087] Typical compound characterization data

[0088] The carbazole derivative (1a), a pale yellow solid. 1 H NMR (400 MHz, CDCl3) δ = 8.82 (d, J = 1.6 Hz, 1H, aromatic CH), 8.20–8.02 (m, 4H, aromatic CH), 7.75–7.66 (m, 3H, aromatic CH), 7.63–7.51 (m, 5H, aromatic CH), 7.39 (dt, J = 8.6, 7.2 Hz, 3H, aromatic CH), 4.05 (s, 3H, NCH3). 13 C{ 1 H}NMR (101 MHz, CDCl3) δ = 194.82, 194.31, 192.96 (Cq each, C=O), 143.41, 141.78, 137.87, 135.05, 133.31, 126.16, 122.70, 119.13 (Cq each), 132.24, 130.26, 129.87, 129.19, 128.40, 128.23, 127.81, 127.60, 121.61, 120.61, 110.33 (aromatic CH), 34.73 (NCH3).C 28 H 19 The HRMS theoretical value of C + HNO3 ([M + H]

[0089] The carbazole derivative (1b), an orange-yellow solid. 1 H NMR (400 MHz, CDCl3) δ = 8.79 (d, J = 1.6 Hz, 1H, aromatic CH), 8.44 (d, J = 1.5 Hz, 1H, aromatic CH), 8.23 (d, J = 1.6 Hz, 1H, aromatic CH), 8.11–8.01 (m, 2H, aromatic CH), 7.85 (dd, J = 8.6 Hz, 1.6, 1H, aromatic CH), 7.77–7.68 (m, 3H, aromatic CH), 7.65 (d, J = 8.6 Hz, 1H, aromatic CH), 7.59–7.54 (m, 3H, aromatic CH), 7.45 (dd, J = 8.4 Hz, 7.0, 2H, aromatic CH), 4.08 (s, 3H, NCH3). 13 C{ 11H NMR (101 MHz, CDCl3) δ = 194.42, 193.66, 192.45 (each Cq, C=O), 144.91, 142.16, 137.27, 135.30, 133.49, 124.65, 122.79, 120.45, 104.62 (each Cq), 132.88, 132.62, 130.75, 130.27, 129.81, 129.24, 129.02, 128.52, 128.41, 125.43, 119.55, 111.15 (aromatic CH), 34.91 (NCH3). C 29 H 18 HRMS theoretical value of N2O3 ([M+H] + ): 443.1317; Measured value: 443.1315.

[0090] The carbazole derivative (1d), a pale yellow solid. 1 1H NMR (400 MHz, CDCl3) δ = 8.81 (d, J = 1.6 Hz, 1H, aromatic CH), 8.18–8.12 (m, 2H, aromatic CH), 8.07–8.03 (m, 2H, aromatic CH), 7.70 (t, J = 7.4 Hz, 1H, aromatic CH), 7.65 (d, J = 8.0 Hz, 2H, aromatic CH), 7.57 (dq, J = 12.6, 7.4 Hz, 4H, aromatic CH), 7.41–7.36 (m, 1H, aromatic CH), 7.21 (d, J = 7.9 Hz, 2H, aromatic CH), 4.06 (s, 3H, NCH3), 2.42 (s, 3H, CH3). 13 C{ 1 1H}NMR (101 MHz, CDCl3) δ = 193.56, 193.20, 191.82 (each Cq, C=O), 142.28, 141.92, 140.57, 133.95, 133.89, 132.18, 124.95, 121.58, 117.93 (each Cq), 132.11, 129.16, 129.00, 128.04, 127.97, 127.09, 126.80, 126.62, 120.42, 119.47, 109.18 (aromatic CH), 33.60 (NCH3), 20.58 (CH3). C 29 H 21 HRMS theoretical value of NO3 ([M+H] +): 432.1521; Measured value: 4321522.

[0091] The carbazole derivative (1f), a pale yellow solid. 1 H NMR (400 MHz, CDCl3) δ = 8.81 (d, J = 1.6 Hz, 1H, aromatic CH), 8.16–8.07 (m, 4H, aromatic CH), 7.77–7.72 (m, 2H, aromatic CH), 7.64–7.54 (m, 3H, aromatic CH), 7.41 (dddd, J = 18.2, 7.9, 6.7, 1.4 Hz, 3H, aromatic CH), 7.24–7.19 (m, 2H, aromatic CH), 4.04 (s, 3H, NCH3). 13 C{ 1 H}NMR (101 MHz, CDCl3) δ = 193.71, 191.43, 191.32 (Cq each, C=O), 167.09, 164.52, 142.26, 140.66, 136.72, 132.03, 128.67, 124.98, 121.53, 117.92 (Cq each), 131.93, 131.17, 128.74, 128.64, 126.71, 126.46, 120.52, 119.49, 115.54, 115.32, 109.20 (aromatic CH), 33.58 (NCH3).C 28 H 18 HRMS theoretical value of C + ): 436.1271; Measured value: 436.1271.

[0092] The above embodiments only represent the implementation modes of the present invention, but should not be construed as limiting the scope of the patent of the present invention. It should be noted that for those skilled in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A method for preparing a polycarbonyl carbazole derivative, characterized in that, The synthetic route is shown in the following reaction formula (1): The preparation method uses indole derivative 2, β-chloroketone derivative 3, and γ-chloroketone derivative 4 as raw materials, palladium salt as a catalyst, which is added to a reaction solvent, and an oxidant, an additive, and a base are added. That is, under alkaline conditions, heating is carried out for the Domino indolylalkenylation-Diels-Alder cycloaddition-dehydrogenative aromatization-C-H oxidation reaction. Among them, the molar ratio of indole derivative 2, β-chloroketone derivative 3, and γ-chloroketone derivative 4 is 1:1:1 - 1:1:6, the reaction temperature is 30 - 150 °C, the reaction time is 1 - 30 hours. After the reaction is completed, the product is separated and characterized by conventional separation and purification methods to synthesize the polycarbonyl carbazole derivative 1; The structural formula of the indole derivative 2 is Its substituents are: R 1 being methyl, ethyl, benzyl or allyl; R 2 being H, methyl, methoxy, cyano, nitro, fluorine, chlorine or ester group; The structural formula of the described β-chloroketone derivative 3 is wherein the substituent R 3 is an aryl group or an alkyl group having 1 to 5 carbon atoms, and the aryl group is a phenyl group substituted with methyl, methoxy, fluorine, chlorine, cyano or ester group; The structural formula of the described γ-chloroketone derivative 4 is Its substituent R 4 is an aryl group or an alkyl group with 1-5 carbon atoms, and the aryl group is a phenyl group substituted with methyl, methoxy, fluorine, chlorine, cyano or ester group; The catalyst is palladium acetate, palladium chloride, tetrakis(triphenylphosphine)palladium, or diphenylphosphine dichloride; the oxidant is copper acetate, copper acetate hydrate, copper chloride hydrate, copper trifluoromethanesulfonate, cuprous chloride; the additive is 2,2,6,6-tetramethylpiperidine 1-oxyl TEMPO; the base is lithium acetate, sodium acetate, cesium acetate, sodium carbonate, or potassium phosphate; The molar ratio of indole derivative 2 to the catalyst is 1:0.05 - 1:0.15, the molar ratio of indole derivative 2 to the oxidant is 1:1 - 1:8, the molar ratio of indole derivative 2 to the additive is 1:1 - 1:8, and the molar ratio of indole derivative 2 to the base is 1:1 - 1:

8.

2. The preparation method of a polycarbonyl carbazole derivative according to claim 1, characterized in that, The reaction solvent is one or more of ethanol, tetrahydrofuran, toluene, chlorobenzene, acetonitrile, and N,N-dimethylformamide.

3. The preparation method of a polycarbonyl carbazole derivative according to claim 1, characterized in that, The catalyst is palladium acetate, and the molar ratio of indole derivative 2 to palladium acetate is 1:0.05 - 1:0.1; the oxidant is copper acetate hydrate, and the molar ratio of indole derivative 2 to copper acetate hydrate is 1:2 - 1:5; the molar ratio of indole derivative 2 to 2,2,6,6-tetramethylpiperidine 1-oxyl is 1:2 - 1:5; the base is sodium acetate, and the molar ratio of indole derivative 2 to sodium acetate is 1:4 - 1:5; the reaction solvent is a mixed solvent of N,N-dimethylformamide and toluene.

4. The preparation method of a polycarbonyl carbazole derivative according to claim 1, characterized in that, The molar ratio of indole derivative 2, β-chloroketone derivative 3, and γ-chloroketone derivative 4 is 1:1:3 - 1:1:

4.

5. The preparation method of a polycarbonyl carbazole derivative according to claim 1, characterized in that, The reaction temperature is 70 - 130 °C, and the reaction time is 12 - 24 hours.

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