Polysubstituted benzo [a] carbazole compound as well as preparation method and application thereof

Abstract

The invention discloses a polysubstituted benzo [a] carbazole compound as well as a preparation method and application thereof. The structural formula of the polysubstituted benzo [a] carbazole compound is # imgabs0 #, wherein R1 is selected from one or more of hydrogen, halogen and organic groups; r2 is selected from one or more of hydrogen, halogen and organic groups. According to the invention, # imgabs 1 # and tBuNC react under the action of a palladium catalyst and alkali to obtain the polysubstituted benzo [a] carbazole compound. The polysubstituted benzo [a] carbazole compound has fluorescence property, and the preparation method has the advantages of simple operation, mild conditions, good regioselectivity, wide substrate applicability and the like, and has good application prospects in the fields of organic luminescent materials, fluorescence detection and synthesis research of other analogues.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic synthesis, and particularly relates to a multi-substituted benzo[a]carbazole compound, a preparation method thereof and an application thereof. Background Art

[0002] Benzo[a]carbazole and its derivatives have rich biological and pharmacological activities, such as antifungal, antitumor, anti-inflammatory, anti-estrogen and kinase inhibition properties. In addition, due to their unique luminescent properties, they are also widely used in the field of materials science. For example, dye-sensitized solar cells and organic light-emitting diodes. However, there are few reports on the synthesis of multi-substituted benzo[a]carbazole compounds with different functionalizations. Therefore, it is also very important to explore novel and efficient methods to synthesize multi-substituted benzo[a]carbazole compounds in one step from simple and readily available raw materials, while improving the adaptability of the reaction and the tolerance of functional groups.

[0003] Isocyanides, as versatile synthons in transition-metal-catalyzed transformations, have been widely used in the synthesis of various valuable heterocyclic compounds in recent years (M. Li, R. Zhang, Q. Gao, H. Jiang, M. Lei, W. Wu, Angew. Chem. Int. Ed. 2022, 61, e202208203; Z.-L. Ren, J.-Y. Qiu, L.-L. Yuan, Y.-F. Yuan, S. Cai, J. Li, C. Kong, P. He, L. Wang, Org. Lett. 2022, 24, 859; S. Zheng, H.-J. Fan, S.-S. Liu, Y. Xu, Z.-W. Zhao, H.-H. Kong, P. He, L. Wang, Z.-L. Ren, Org. Chem. Front. 2024, 11, 1775; S. Plunkett, J. B. Diccianni, R. Panish, J. Balsells, Org. Lett. 2024, 26, 6933.). Functionalized diarylalkynes are often used to construct fused aromatic heterocyclic compounds due to their rich reaction sites, but the synthesis of multi-substituted benzo[a]carbazole compounds using isocyanides and functionalized diarylalkynes has not been reported yet. Summary of the Invention

[0004] Aiming at the deficiencies existing in the prior art, the purpose of the present invention is to provide a multi-substituted benzo[a]carbazole compound, a preparation method thereof and an application thereof. The present invention realizes the synthesis of multi-substituted benzo[a]carbazole compounds through the tandem cyclization process of isonitrile and functionalized diarylalkyne compounds catalyzed by a palladium catalyst, which is atomically and step-economical and efficient, and has a wide substrate applicability. In addition to the innovation in synthetic methodology, it also has certain application prospects in the fields of organic light-emitting materials and fluorescence detection.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A multi-substituted benzo[a]carbazole compound has the structural formula:

[0007]

[0008] Among them, R 1 is selected from one or more of hydrogen, halogen, and organic groups; R 2 is selected from one or more of hydrogen, halogen, and organic groups.

[0009] The substituents R 1 and R 2 are each 4 in number and are each independently selected from one of hydrogen, halogen, and organic groups.

[0010] Preferably, the halogen is one or more of fluorine, chlorine, and bromine; the organic group is one or more of substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy, and substituted or unsubstituted C1-C6 ester group; the substituent is halogen (fluorine, chlorine, bromine).

[0011] Preferably, the R 1 is selected from one or more of hydrogen, 3-chloro, 4-tert-butyl, 4-methoxycarbonyl, 5-methyl, 5-methoxy, 5-fluoro, 5-chloro, 5-bromo, 5-trifluoromethyl, 4,5-dimethyl; the R 2 is selected from one or more of hydrogen, 4-fluoro, 5-fluoro, and 5-methoxy.

[0012] The preparation method of the above-mentioned multi-substituted benzo[a]carbazole compound includes the following steps:

[0013] and t BuNC reacts under the action of a palladium catalyst and a base to obtain a multi-substituted benzo[a]carbazole compound.

[0014] Preferably, the molar ratio of the t BuNC, palladium catalyst and base is 1:1.0-3.0:0.05-0.1:1.0-3.0.

[0015] Preferably, the palladium catalyst is at least one of tetrakis(triphenylphosphine)palladium, palladium iodide, bis(triphenylphosphine)palladium dichloride, and palladium acetate.

[0016] Preferably, the base is at least one of DBU, sodium carbonate, sodium bicarbonate, sodium hydroxide, potassium carbonate, and cesium carbonate.

[0017] Preferably, the reaction temperature is 80-100 °C and the reaction time is 8-16 hours.

[0018] Preferably, the preparation method of the above-mentioned polysubstituted benzo[a]carbazole compounds comprises the following steps:

[0019] Dissolve t BuNC, palladium catalyst, and base in a solvent, stir and react at 80-100 °C, cool to room temperature after the reaction, and separate and purify the product to obtain polysubstituted benzo[a]carbazole compounds.

[0020] More preferably, the t molar ratio of BuNC, palladium catalyst, and base is 1:1.0-3.0:0.05-0.1:1.0-3.0.

[0021] More preferably, the palladium catalyst is at least one of tetrakis(triphenylphosphine)palladium, palladium iodide, bis(triphenylphosphine)palladium dichloride, and palladium acetate.

[0022] More preferably, the base is at least one of DBU, sodium carbonate, sodium bicarbonate, sodium hydroxide, potassium carbonate, and cesium carbonate.

[0023] More preferably, the solvent is at least one of acetonitrile, toluene, tetrahydrofuran, dichloroethane, methanol, dimethyl sulfoxide, and 1,4-dioxane.

[0024] More preferably, the reaction time is 8-16 hours.

[0025] More preferably, the specific operation of the separation and purification is as follows: extract the reaction solution with ethyl acetate 3-5 times, combine the organic phases, dry with anhydrous sodium sulfate, filter, distill off the organic solvent under reduced pressure from the filtrate to obtain a crude product, and purify it by column chromatography to obtain polysubstituted benzo[a]carbazole compounds.

[0026] Even more preferably, the eluent for column chromatography is composed of petroleum ether and ethyl acetate in a volume ratio of 5-3:1.

[0027] The above-mentioned polysubstituted benzo[a]carbazole compounds are used as organic light-emitting materials or in the preparation of organic light-emitting materials.

[0028] Application of the above-mentioned multi-substituted benzo[a]carbazole compounds as fluorescent probes.

[0029] Preferably, the multi-substituted benzo[a]carbazole compounds can distinguish different solvents.

[0030] Principle of the present invention: Using functionalized diarylalkyne compounds and tert-butyl isocyanide as raw materials, reacting under the action of a palladium catalyst and a base, through sequential insertion of alkynes and isocyanides, followed by intramolecular cyclization, reductive elimination, and 1,5-acyl migration to obtain multi-substituted benzo[a]carbazole compounds.

[0031] Beneficial effects of the present invention are:

[0032] The present invention synthesizes a series of brand-new multi-substituted benzo[a]carbazole compounds, which have fluorescence properties, and the preparation method has the advantages of simple and easily available raw materials, simple operation, mild conditions, good regioselectivity, and wide substrate adaptability, and has good application prospects in the fields of organic light-emitting materials, fluorescence detection, and synthesis research of other analogues. Description of the Drawings

[0033] Figure 1 and Figure 2 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 1.

[0034] Figure 3 and Figure 4 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 2.

[0035] Figure 5 and Figure 6 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 3.

[0036] Figure 7 and Figure 8 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 4.

[0037] Figure 9 and Figure 10 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 5.

[0038] Figure 11 and Figure 12 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 6.

[0039] Figure 13 and Figure 14 are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 7.

[0040] Figure 15 and Figure 16They are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 8.

[0041] Figure 17 and Figure 18 They are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 10.

[0042] Figure 19 and Figure 20 They are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 12.

[0043] Figure 21 and Figure 22 They are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 13.

[0044] Figure 23 and Figure 24 They are respectively the hydrogen spectrum and carbon spectrum of the target product obtained in Example 14.

[0045] Figure 25 They are the fluorescence emission spectra of the target products in Examples 1, 5, 6, 7, and 10.

[0046] Figure 26 They are the fluorescence emission spectra of the target product in Example 1 mixed with different solvents. Detailed implementation mode

[0047] The technical solutions of the present invention will be further described in detail below in conjunction with specific embodiments and the accompanying drawings, but the protection scope and implementation mode of the present invention are not limited thereto.

[0048] In the following examples, 1.0 equivalent is 0.1 mmol.

[0049] Example 1

[0050] Add (1.0 equivalent), t BuNC (2.0 equivalents), Pd(PPh 3 ) 4 (0.1 equivalent), DBU (2.0 equivalents) and acetonitrile (2 mL) into a reaction tube, stir and react at 90 °C and 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases and dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 76%.

[0051] The hydrogen spectrum and carbon spectrum of the obtained target product are respectively as Figure 1 and Figure 2 shown, and the structure characterization data are as follows:

[0052] 11H NMR (400 MHz, DMSO-d 6 ) δ 13.21 (s, 1H), 8.76 (dd, J = 7.4, 2.2 Hz, 1H), 8.28 (dd, J = 6.9, 1.7 Hz, 1H), 8.03 (d, J = 8.1 Hz, 1H), 7.95–7.87 (m, 2H), 7.79 (d, J = 8.1 Hz, 1H), 7.56 (t, J = 7.7 Hz, 1H), 7.38 (t, J = 7.6 Hz, 1H), 1.52 (s, 9H).

[0053] 13 13C NMR (101 MHz, DMSO-d 6 ) δ 155.6 (q, J = 34.7 Hz), 139.5, 139.1, 136.4, 129.7, 129.0, 128.3, 126.5, 125.9, 123.0, 121.1, 121.0, 120.3, 117.3, 115.6 (q, J = 289.1 Hz), 116.8, 112.5, 102.7, 65.8, 28.0.

[0054] 19 19F NMR (376 MHz, DMSO-d 6 ) δ -68.6.

[0055] HRMS (APCI) calcd for C 23 19 19 F 3 15 3 O [M+H] + : 410.1475, Found: 410.1474.

[0056] Based on the above data, the structure of the target product is as follows:

[0057]

[0058] Example 2

[0059] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL) into a reaction tube, stir the reaction at 90 °C and 500 rpm for 12 h. After the reaction is completed, extract with ethyl acetate three times, combine the organic phases, dry over anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 3:1 to obtain the target product with a yield of 43%.

[0060] The hydrogen spectrum and carbon spectrum of the obtained target product are shown in Figure 3 and Figure 4 respectively, and the structural characterization data are as follows:

[0061] 1 H NMR(400MHz, DMSO-d 6 ) δ13.56(s, 1H), 8.80–8.74(m, 1H), 8.30–8.25(m, 1H), 8.00–7.91(m, 2H), 7.80(d, J=7.1Hz, 1H), 7.57(t, J=7.9Hz, 1H), 7.44(d, J=7.6Hz, 1H), 1.34(s, 9H).

[0062] 13 C NMR(101MHz, DMSO-d 6 ) δ155.8(q, J=33.8Hz), 141.6, 139.9, 137.1, 129.7, 129.6, 128.7, 127.4, 125.7, 125.5, 123.4, 123.0, 120.2, 119.4, 117.2, 116.0(q, J=289.2Hz), 115.2, 111.6, 104.2, 66.1, 27.9.

[0063] 19 F NMR(376MHz, DMSO-d 6 ) δ - 67.0.

[0064] HRMS(APCI) calcd for C 23 H 18 ClF 3 N 3 O [M + H] + : 444.1085, Found: 444.1084.

[0065] Based on the above data, the structure of the target product is inferred as follows:

[0066]

[0067] Example 3

[0068] Add 1.0 equivalent), t BuNC(2.0 equivalents), Pd(PPh 3 ) 4(0.1 eq), DBU (2.0 eq) and acetonitrile (2 mL) were stirred at 90 °C and 500 rpm for 12 h. After the reaction, the mixture was extracted three times with ethyl acetate. The combined organic phases were dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and then purified by column chromatography. The eluent was a petroleum ether:ethyl acetate mixed solvent with a volume ratio of 5:1 to obtain the target product with a yield of 70%.

[0069] The 1H NMR and 13C NMR spectra of the obtained target product are shown in Figure 5 and Figure 6 respectively, and the structure characterization data are as follows:

[0070] 1 1H NMR (400 MHz, DMSO-d 6 ) δ 13.09 (s, 1H), 8.73 (dd, J = 7.6, 1.8 Hz, 1H), 8.27 (dd, J = 7.5, 1.8 Hz, 1H), 8.01 (s, 1H), 7.92–7.84 (m, 2H), 7.71 (d, J = 8.6 Hz, 1H), 7.64 (dd, J = 8.6, 1.8 Hz, 1H), 1.53 (s, 9H), 1.33 (s, 9H).

[0071] 13 13C NMR (101 MHz, DMSO-d 6 ) δ 155.8 (q, J = 34.5 Hz), 143.3, 139.3, 137.6, 136.5, 129.6, 128.8, 128.1, 125.8, 124.4, 122.9, 120.8, 120.3, 117.4, 117.1, 116.9, 115.6 (q, J = 289.0 Hz), 112.0, 102.2, 65.7, 34.5, 31.5, 28.0.

[0072] 19 19F NMR (376 MHz, DMSO-d 6 ) δ -68.8.

[0073] HRMS (APCI) calcd for C 27 H 27 N 3 F 3 O [M+H] + : 466.2101, Found: 466.2103.

[0074] Based on the above data, the structure of the target product is inferred as follows:

[0075]

[0076] Example 4

[0077] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL), stir and react at 90 °C with a rotation speed of 500 rpm for 12 h. After the reaction, extract three times with ethyl acetate, combine the organic phases, dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 49%.

[0078] The hydrogen spectrum and carbon spectrum of the obtained target product are respectively as Figure 7 and Figure 8 shown, and the structural characterization data are as follows:

[0079] 1 H NMR (400 MHz, DMSO-d 6 ) δ 13.55 (s, 1H), 8.79 (s, 1H), 8.75 (dd, J = 7.4, 2.3 Hz, 1H), 8.31–8.27 (m, 1H), 8.14 (dd, J = 8.6, 1.6 Hz, 1H), 7.97–7.89 (m, 2H), 7.85 (d, J = 8.6 Hz, 1H), 3.89 (s, 3H), 1.53 (s, 9H).

[0080] 13 C NMR (101 MHz, DMSO-d 6 ) δ 166.4, 155.6 (q, J = 34.7 Hz), 142.2, 140.1, 136.2, 130.0, 129.5, 128.7, 127.1, 126.0, 123.2, 123.0, 122.2, 120.9, 120.5, 117.0, 115.6 (q, J = 289.0 Hz), 112.6, 104.0, 65.9, 52.2, 27.9.

[0081] 19 F NMR (376 MHz, DMSO-d 6 ) δ -68.7.

[0082] HRMS (APCI) calcd for C 25 H 21 N 3 F 3 O 3 [M+H]+ : 468.1530, Found: 468.1532.

[0083] Based on the above data, the structure of the target product is as follows:

[0084]

[0085] Example 5

[0086] Add (1.0 equivalent), t BuNC (2.0 equivalents), Pd(PPh 3 ) 4 (0.1 equivalent), DBU (2.0 equivalents) and acetonitrile (2 mL) into the reaction tube, stir and react at 90 °C with a rotation speed of 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 3:1 to obtain the target product with a yield of 70%.

[0087] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are respectively as Figure 9 and Figure 10 shown, and the structure characterization data are as follows:

[0088] 1 1H NMR (400 MHz, DMSO-d 6 ) δ 13.04 (s, 1H), 8.73 (dd, J = 7.7, 2.0 Hz, 1H), 8.25 (dd, J = 7.7, 2.0 Hz, 1H), 7.91–7.86 (m, 2H), 7.86–7.82 (m, 1H), 7.55 (s, 1H), 7.18 (dd, J = 8.3, 1.5 Hz, 1H), 2.50 (s, 3H), 1.49 (s, 9H).

[0089] 13 13C NMR (101 MHz, DMSO-d 6 ) δ 155.6 (q, J = 34.6 Hz), 140.0, 138.9, 136.5, 136.1, 129.6, 128.7, 128.1, 125.8, 122.7, 122.6, 120.8, 120.3, 118.8, 117.4, 117.0, 115.7 (q, J = 289.0 Hz), 112.2, 102.4, 65.6, 28.0, 21.5.

[0090] 19 19F NMR (376 MHz, DMSO-d 6) δ - 68.7.

[0091] HRMS(APCI) calcd for C 24 H 21 N 3 F 3 O[M + H] + : 424.1631, Found: 424.1630.

[0092] Based on the above data, the structure of the target product is as follows:

[0093]

[0094] Example 6

[0095] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL) into the reaction tube, stir and react at 90 °C and 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 67%.

[0096] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are shown in Figure 11 and Figure 12 respectively, and the structure characterization data are as follows:

[0097] 1 H NMR(400 MHz, DMSO-d 6 ) δ 13.07(s, 1H), 8.69(dd, J = 8.4, 1.3 Hz, 1H), 8.25(dd, J = 8.5, 1.2 Hz, 1H), 7.91–7.87(m, 2H), 7.86–7.82(m, 1H), 7.21(d, J = 2.3 Hz, 1H), 7.03(dd, J = 8.8, 2.4 Hz, 1H), 3.90(s, 3H), 1.51(s, 9H).

[0098] 13 C NMR(101 MHz, DMSO-d 6) δ 158.9, 155.7 (q, J = 34.6 Hz), 141.1, 138.9, 135.6, 129.2, 128.5, 128.1, 125.8, 122.7, 122.0, 120.1, 117.4, 117.3, 115.7 (q, J = 289.0 Hz), 114.8, 110.6, 102.4, 95.5, 65.6, 55.5, 28.0.

[0099] 19 F NMR (376 MHz, DMSO-d 6 ) δ -68.7.

[0100] HRMS (APCI) calcd for C 24 H 21 N 3 F 3 O 2 [M + H] + : 440.1580, Found: 440.1581.

[0101] Based on the above data, the structure of the target product is as follows:

[0102]

[0103] Example 7

[0104] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL) into a reaction tube, stir the reaction at 90 °C and 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry over anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 41%.

[0105] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are shown in Figure 13 and Figure 14 respectively, and the structure characterization data are as follows:

[0106] 1 1H NMR (400 MHz, DMSO-d 6)δ13.33(s,1H),8.73(dd,J=7.0,1.6Hz,1H),8.27(dd,J=8.2,1.4Hz,1H),8.02(dd,J=8.9,5.2Hz,1H),7.95–7.87(m,2H),7.55(dd,J=9.4,2.4Hz,1H),7.26(td,J=9.2,2.4Hz,1H),1.51(s,9H).

[0107] 13 C NMR(101MHz,DMSO-d 6 )δ161.6(d,J=240.6Hz),156.1(q,J=34.7Hz),140.7(d,J=12.7Hz),140.2(d,J=1.7Hz),136.4,130.0,129.5,128.9,126.4,123.3,123.1(d,J=10.5Hz),120.7,118.3,117.6,117.1,116.0(q,J=289.0Hz),110.0(d,J=24.4Hz),103.7,99.4(d,J=25.8Hz),66.3,28.5.

[0108] 19 F NMR(376MHz,DMSO-d 6 )δ-68.7,-113.79(td,J=9.4,5.2Hz).

[0109] HRMS(APCI)calcd for C 23 H 18 N 3 F 4 O[M+H] + :428.1381,Found:428.1384.

[0110] Based on the above data, the structure of the target product is as follows:

[0111]

[0112] Example 8

[0113] Add (1.0 equivalent), t BuNC(2.0 equivalents), Pd(PPh 3 ) 4(0.1 eq), DBU (2.0 eq) and acetonitrile (2 mL) were stirred and reacted at 90 °C with a rotation speed of 500 rpm for 12 hours. After the reaction, it was extracted three times with ethyl acetate. The organic phases were combined, dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and then separated and purified by column chromatography. The eluent was a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 40%.

[0114] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are shown in Figure 15 and Figure 16 respectively, and the structure characterization data are as follows:

[0115] 1 H NMR (400 MHz, DMSO-d 6 ) δ 13.34 (s, 1H), 8.73 (dd, J = 7.4, 1.9 Hz, 1H), 8.28 (dd, J = 7.5, 1.9 Hz, 1H), 8.00 (d, J = 8.6 Hz, 1H), 7.95–7.88 (m, 2H), 7.79 (d, J = 1.9 Hz, 1H), 7.42 (dd, J = 8.6, 2.0 Hz, 1H), 1.50 (s, 9H).

[0116] 13 C NMR (101 MHz, DMSO-d 6 ) δ 156.0 (q, J = 34.7 Hz), 140.6, 140.1, 136.6, 131.5, 130.3, 129.7, 129.0, 126.5, 123.5, 122.9, 121.9, 120.8, 120.4, 117.5, 116.9, 116.1 (q, J = 289.2 Hz), 112.6, 104.0, 66.3, 28.5.

[0117] 19 F NMR (376 MHz, DMSO-d 6 ) δ -68.7.

[0118] HRMS (APCI) calcd for C 23 H 18 ClN 3 F 3 O [M+H] + : 444.1085, Found: 444.1086.

[0119] Based on the above data, the structure of the target product is inferred as follows:

[0120]

[0121] Example 9

[0122] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL), stir the reaction at 90 °C and 500 rpm for 12 h. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry over anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 36%.

[0123] The structural characterization data of the obtained target product are as follows:

[0124] 1 H NMR (400 MHz, DMSO-d 6 ) δ 13.34 (s, 1H), 8.73 (dd, J = 8.2, 1.5 Hz, 1H), 8.28 (dd, J = 7.3, 2.0 Hz, 1H), 7.98–7.93 (m, 2H), 7.93–7.88 (m, 2H), 7.55 (dd, J = 8.6, 1.9 Hz, 1H), 1.50 (s, 9H).

[0125] 13 C NMR (101 MHz, DMSO-d 6 ) δ 155.5 (q, J = 34.6 Hz), 140.4, 139.4, 136.1, 129.8, 129.3, 128.5, 126.0, 124.1, 123.0, 122.7, 120.3, 120.2, 119.2, 117.0, 116.4, 115.6 (q, J = 288.8 Hz), 115.1, 103.5, 65.9, 28.0.

[0126] 19 F NMR (376 MHz, DMSO-d 6 ) δ -68.7.

[0127] HRMS (APCI) calcd for C 23 H 18 BrN 3 F 3 O [M+H] + : 488.0580, Found: 488.0582.

[0128] Based on the above data, the structure of the target product is inferred as follows:

[0129]

[0130] Example 10

[0131] Add (1.0 equivalent), t BuNC (2.0 equivalents), Pd(PPh 3 ) 4 (0.1 equivalent), DBU (2.0 equivalents) and acetonitrile (2 mL) into the reaction tube, stir and react at 90 °C with a rotation speed of 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 50%.

[0132] The hydrogen NMR spectrum and carbon NMR spectrum of the obtained target product are respectively as Figure 17 and Figure 18 shown, and the structure characterization data are as follows:

[0133] 1 H NMR (400 MHz, DMSO-d 6 ) δ 13.59 (s, 1H), 8.77 (dd, J = 7.9, 1.6 Hz, 1H), 8.31 (dd, J = 7.9, 1.6 Hz, 1H), 8.23 (d, J = 8.4 Hz, 1H), 8.05 (d, J = 1.7 Hz, 1H), 8.00–7.95 (m, 2H), 7.73 (dd, J = 8.5, 1.7 Hz, 1H), 1.52 (s, 9H).

[0134] 13 C NMR (101 MHz, DMSO-d 6 ) δ 155.5 (q, J = 34.7 Hz), 140.5, 138.6, 136.5, 130.0, 129.7, 128.8, 126.5, 126.1, 125.9, 123.8, 123.2, 122.0, 120.4, 117.4 (q, J = 3.6 Hz), 116.9, 116.0, 115.6 (q, J = 289.0 Hz), 109.6 (q, J = 4.1 Hz), 104.0, 66.0, 28.0.

[0135] 19 F NMR (376 MHz, DMSO-d 6 ) δ -59.8, -68.7.

[0136] HRMS (APCI) calcd for C24 H 18 N 3 F 6 O[M+H] + :478.1349, Found:478.1348.

[0137] Based on the above data, the structure of the target product is as follows:

[0138]

[0139] Example 11

[0140] Add (1.0 equivalent), t BuNC (2.0 equivalents), Pd(PPh 3 ) 4 (0.1 equivalent), DBU (2.0 equivalents) and acetonitrile (2 mL) into the reaction tube, stir and react at 90 °C and 500 rpm for 12 hours. After the reaction, extract three times with ethyl acetate, combine the organic phases, dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 57%.

[0141] The structural characterization data of the obtained target product are as follows:

[0142] 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.96 (s, 1H), 8.72 (dd, J = 8.3, 1.3 Hz, 1H), 8.25 (dd, J = 7.6, 1.7 Hz, 1H), 7.91–7.82 (m, 2H), 7.78 (s, 1H), 7.55 (s, 1H), 2.42 (s, 3H), 2.37 (s, 3H), 1.52 (s, 9H).

[0143] 13 C NMR (101 MHz, DMSO-d 6 ) δ 155.6 (q, J = 34.6 Hz), 138.7, 138.4, 136.1, 135.8, 129.5, 129.3, 128.6, 128.0, 125.8, 122.8, 121.1, 120.3, 119.2, 117.4, 116.9, 115.7 (q, J = 289.1 Hz), 112.6, 102.1, 65.6, 27.9, 20.2, 20.1.

[0144] 19 F NMR (376 MHz, DMSO-d6 ) δ - 68.6.

[0145] HRMS(APCI) calcd for C 25 H 23 N 3 F 3 O [M + H] + : 438.1788, Found: 438.1787.

[0146] Based on the above data, the structure of the target product is as follows:

[0147]

[0148] Example 12

[0149] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL) into the reaction tube, stir and react at 90 °C with a rotation speed of 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry with anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 49%.

[0150] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are shown in Figure 19 and Figure 20 respectively, and the structure characterization data are as follows:

[0151] 1 H NMR (400 MHz, DMSO-d 6 ) δ 13.18 (s, 1H), 8.53 (dd, J = 9.9, 2.6 Hz, 1H), 8.33 (dd, J = 9.2, 5.3 Hz, 1H), 8.04 (d, J = 8.0 Hz, 1H), 7.79 (td, J = 8.6, 2.5 Hz, 2H), 7.60–7.56 (m, 1H), 7.42–7.38 (m, 1H), 1.51 (s, 9H).

[0152] 13 C NMR (101 MHz, DMSO-d 6) δ 161.2 (d, J = 246.3 Hz), 155.6 (q, J = 34.7 Hz), 139.5, 138.4 (d, J = 4.5 Hz), 135.9, 129.2 (d, J = 9.5 Hz), 126.8, 126.6, 121.5, 121.4, 121.2 (d, J = 7.6 Hz), 120.9, 118.6 (d, J = 25.0 Hz), 117.2, 117.1, 115.6 (q, J = 289.0 Hz), 112.6, 107.5 (d, J = 23.3 Hz), 102.8, 65.9, 28.0.

[0153] 19 F NMR (376 MHz, DMSO-d 6 ) δ -68.6, -110.23 (td, J = 9.0, 5.4 Hz).

[0154] HRMS (APCI) calcd for C 23 H 18 N 3 F 4 O [M + H] + : 428.1381, Found: 428.1380.

[0155] Based on the above data, the structure of the target product is as follows:

[0156]

[0157] Example 13

[0158] Add (1.0 equiv), t BuNC (2.0 equiv), Pd(PPh 3 ) 4 (0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL) into the reaction tube, stir the reaction at 90 °C and 500 rpm for 12 hours. After the reaction is completed, extract three times with ethyl acetate, combine the organic phases, dry over anhydrous sodium sulfate, filter, concentrate under reduced pressure, and then separate and purify by column chromatography. The eluent is a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 70%.

[0159] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are shown in Figure 21 and Figure 22 respectively, and the structure characterization data are as follows:

[0160] 1 1H NMR (400 MHz, DMSO-d 6)δ13.26(s,1H),8.83(dd,J=9.1,5.4Hz,1H),8.02(d,J=8.0Hz,1H),7.90(dd,J=10.1,2.6Hz,1H),7.86(td,J=8.7,2.5Hz,1H),7.79(d,J=8.2Hz,1H),7.59–7.53(m,1H),7.42–7.36(m,1H),1.51(s,9H).

[0161] 13 C NMR(101MHz,DMSO-d 6 )δ161.8(d,J=246.9Hz),155.5(q,J=34.7Hz),139.5,139.2,137.4,131.3(d,J=9.6Hz),126.6,126.3(d,J=9.5Hz),121.1(d,J=5.3Hz),120.9,118.2,118.0,117.4,117.0,116.7,115.6(q,J=288.9Hz),112.6,110.0(d,J=23.3Hz),102.0(d,J=4.1Hz),65.9,28.0.

[0162] 19 F NMR(376MHz,DMSO-d 6 )δ-68.6,-109.6(td,J=9.3,5.5Hz).

[0163] HRMS(APCI)calcd for C 23 H 18 N 3 F 4 O[M] + :428.1381,Found:428.1378.

[0164] Based on the above data, the structure of the target product is as follows:

[0165]

[0166] Example 14

[0167] Add (1.0 equivalent), t BuNC(2.0 equivalents), Pd(PPh 3 ) 4(0.1 equiv), DBU (2.0 equiv) and acetonitrile (2 mL) were stirred at 90 °C and 500 rpm for 12 h. After the reaction, the mixture was extracted three times with ethyl acetate. The organic phases were combined, dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and then purified by column chromatography. The eluent was a mixed solvent of petroleum ether:ethyl acetate with a volume ratio of 5:1 to obtain the target product with a yield of 73%.

[0168] The 1H NMR spectrum and 13C NMR spectrum of the obtained target product are shown in Figure 23 and Figure 24 respectively, and the structural characterization data are as follows:

[0169] 1 H NMR (400 MHz, DMSO-d 6 ) δ 13.03 (s, 1H), 8.66 (d, J = 8.9 Hz, 1H), 7.99 (d, J = 8.0 Hz, 1H), 7.74 (d, J = 8.1 Hz, 1H), 7.59–7.55 (m, 2H), 7.54–7.50 (m, 1H), 7.37–7.33 (m, 1H), 4.00 (s, 3H), 1.52 (s, 9H).

[0170] 13 C NMR (101 MHz, DMSO-d 6 ) δ 159.7, 155.6 (q, J = 34.6 Hz), 139.5, 139.5, 136.6, 131.9, 126.2, 124.8, 121.1, 120.9, 120.8, 112.0, 117.6, 115.8, 115.7 (q, J = 289.0 Hz), 115.0, 112.3, 104.9, 101.6, 65.7, 55.5, 28.0.

[0171] 19 F NMR (376 MHz, DMSO-d 6 ) δ -68.6.

[0172] HRMS (APCI) calcd for C 24 H 21 N 3 F 3 O 2 [M] + : 440.1580, Found: 440.1579.

[0173] Based on the above data, the structure of the target product is inferred as follows:

[0174]

[0175] Application test:

[0176] 1) Respectively prepare 10 mL of acetonitrile solutions with a concentration of 10 -3 M for the target benz[a]carbazole compounds in Examples 1, 5, 6, 7, and 10. Then, respectively take 20 μL of the target product solution and mix it evenly with 2 mL of acetonitrile, and then conduct fluorescence tests on them. The corresponding fluorescence emission spectra of the target products are as Figure 25 shown.

[0177] As Figure 25 can be seen, the benz[a]carbazole compounds in Examples 1, 5, 6, 7, and 10 all have excellent fluorescence properties. Among them, the product with an electron-donating methoxy substitution shows an obvious decrease in fluorescence intensity, while other substituents do not show an obvious intensity decrease, indicating that the electronic effect may affect the fluorescence absorption and fluorescence emission of the product.

[0178] After testing, the products in other examples also have excellent fluorescence properties and can be applied to the synthesis of fluorescent materials.

[0179] 2) Respectively prepare 10 mL of 1,4-dioxane, methanol, 1,2-dichloroethane, N,N-dimethylformamide, tetrahydrofuran, and toluene solutions with a concentration of 10 -3 M for the target benz[a]carbazole compound in Example 1. Then, respectively take 20 μL of the target product solution and mix it evenly with 2 mL of different solvents, and then conduct fluorescence tests on them. The corresponding fluorescence emission spectra of the target products are as Figure 26 shown.

[0180] As Figure 26 can be seen, N,N-dimethylformamide is a solvent that can cause an obvious decrease in the fluorescence intensity of the target product, while other solvents have a relatively small effect on the fluorescence intensity change.

[0181] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A polysubstituted benzo[a]carbazole compound, characterized in that: The structural formula is: Among them, R 1 One or more selected from hydrogen, halogen, and organic groups; R 2 One or more selected from hydrogen, halogen, and organic groups.

2. The polysubstituted benzo[a]carbazole compound according to claim 1, characterized in that: The R 1 One or more selected from hydrogen, 3-chloro, 4-tert-butyl, 4-methoxycarbonyl, 5-methyl, 5-methoxy, 5-fluoro, 5-chloro, 5-bromo, 5-trifluoromethyl, 4,5-dimethyl; The R 2 One or more selected from hydrogen, 4-fluoro, 5-fluoro, and 5-methoxy.

3. The method for preparing a polysubstituted benzo[a]carbazole compound according to claim 1 or 2, characterized in that: The following steps are involved: and t BuNC reacts under the action of palladium catalyst and base to obtain multi-substituted benzo[a]carbazole compounds.

4. The method for preparing a polysubstituted benzo[a]carbazole compound according to claim 3, characterized in that: The following steps are involved: Will t BuNC, palladium catalyst and base are dispersed in a solvent, stirred and reacted at 80-100° C., cooled to room temperature after the reaction is completed, and the product is separated and purified to obtain a polysubstituted benzo[a]carbazole compound.

5. The method for preparing a polysubstituted benzo[a]carbazole compound according to claim 3 or 4, characterized in that: Said t The molar ratio of BuNC, palladium catalyst and base is 1:1.0-3.0:0.05-0.1:1.0-3.

0.

6. The method for preparing a polysubstituted benzo[a]carbazole compound according to claim 3 or 4, characterized in that: The palladium catalyst is at least one of tetrakis(triphenylphosphine)palladium, palladium iodide, bis(triphenylphosphine)palladium dichloride, and palladium acetate; The base is at least one of DBU, sodium carbonate, sodium bicarbonate, sodium hydroxide, potassium carbonate and cesium carbonate.

7. The method for preparing a polysubstituted benzo[a]carbazole compound according to claim 4, characterized in that: The solvent is at least one of acetonitrile, toluene, tetrahydrofuran, dichloroethane, methanol, dimethyl sulfoxide and 1,4-dioxane.

8. The method for preparing a polysubstituted benzo[a]carbazole compound according to claim 3 or 4, characterized in that: The reaction time is 8 to 16 hours.

9. Use of the polysubstituted benzo[a]carbazole compound according to claim 1 or 2 as an organic light-emitting material or in the preparation of an organic light-emitting material.

10. Use of the polysubstituted benzo[a]carbazole compound according to claim 1 or 2 as a fluorescent probe.

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