A method for the gold-light synergistically catalyzed synthesis of benzo[c,g]carbazole compounds

Abstract

The method for synthesizing a benz [c, g] carbazole compound through gold-light synergistic catalysis belongs to the technical field of organic gold catalysis and photocatalysis, and comprises the following steps: gold catalyst and Lewis acid catalyst are added into a mixed toluene solution of a nitrogen methyl pyrrole and a diphenylacetylene compound; the obtained reaction liquid is reacted at 60 DEG C for 10 hours; after the reaction is completed, the obtained product is separated and purified, dissolved in cyclohexane, and I2 is added into the obtained solution under the irradiation of an ultraviolet lamp; the obtained solution is stirred at room temperature for 6 hours; after the reaction is completed, the benz [c, g] carbazole compound is separated and purified. The synthesis and characterization of a bis-benz [c, g] carbazole compound and a bis-olefin precursor are realized for the first time, the reaction condition is simple, the adaptability of the substrate is relatively wide, and the method is a very excellent synthesis strategy.

Description

Technical fields:

[0001] This invention belongs to the field of organogold catalysis and photocatalysis technology, specifically relating to a method for synthesizing bisbenzo[c,g]carbazole compounds by gold catalysis and photocatalysis. Background technology:

[0002] In recent decades, carbazole compounds, as a type of polycyclic aromatic hydrocarbon (PAH), have attracted considerable attention from scientists, not only because of their significant biological and pharmacological activities, but also because of their unique electrochemical and photochemical properties. Among them, nitrogen-excess aromatic heterocycles, particularly carbazoles, indolecarbazoles, benzo[a]carbazoles, and carboline compounds, have been considered a fundamental framework of organic chemistry for decades due to their ubiquitous presence in natural products, alkaloids, terpenes, marketed drugs, pharmaceutically active compounds, and organic materials. With their increasing importance, they have achieved a wide range of significant developments and applications in synthesis over the past decade.

[0003] In synthetic organic chemistry, cyclization strategies have proven to be a valuable auxiliary tool and a core pillar in the concise synthesis of complex structures from natural alkaloids, drugs, terpenes, steroids, and more. The term "cyclization" originates from the Latin word "anellus," describing the process of fusing a new ring into a pre-existing system by forming two new bonds. Among various types of cyclization strategies, benzyl cyclization offers an elegant route to obtain a multitude of aromatic compounds with diverse properties. Previously synthesized benzyl cyclization schemes have been used to construct carbazoles, benzo[a]carbazoles, indole[a]carbazoles, and carboline compounds. These N-heterocyclic compounds, due to their widespread presence in various natural products, serve as privileged structural motifs, pharmaceuticals, and bioactive compounds. Furthermore, these structurally important components exhibit ubiquitous applications in materials and medicinal chemistry.

[0004] Over the past few decades, numerous synthetic methods have been developed for constructing these carbazole-based polycyclic aromatic hydrocarbon systems. However, methods for synthesizing this class of nitrogen-containing polycyclic aromatic compounds using gold catalysis and photocatalysis have not yet been reported. Gold catalysis has been widely used in homogeneous catalysis in recent decades, while photocatalysis has long been considered a highly efficient cyclization method. Therefore, this application utilizes gold catalysis and photocatalysis to design and synthesize a series of bisbenzo[c,g]carbazole products. Summary of the Invention:

[0005] To address the shortcomings of existing technologies, this invention provides a gold-catalyzed and photocatalytic method for the synthesis of bisbenzo[c,g]carbazole compounds. This catalytic method features high catalytic efficiency, mild reaction conditions, broad substrate applicability, and high atom utilization.

[0006] The technical solution of the present invention is as follows:

[0007] A method for synthesizing benzo[c,g]carbazole compounds by gold-photocatalytic co-catalysis includes the following steps:

[0008] (1) Add a gold catalyst and a Lewis acid catalyst to a mixed toluene solution of compound 1 and compound 2, and react the resulting reaction solution at 60°C for 10 h. After the reaction is complete, separate and purify to obtain compound 3; compound 1 is N-methylpyrrole; compound 2 is a diphenylacetylene compound; the ratio of compound 1, compound 2, gold catalyst and Lewis acid is 1:3:0.15:0.2.

[0009] (2) Dissolve compound 3 obtained in step (1) in cyclohexane, add I2 to the resulting solution under ultraviolet light, stir at room temperature for 6 hours, and after the reaction is completed, separate and purify to obtain compound 4, namely benzo[c,g]carbazole compound; the molar ratio of compound 3 to I2 is 1:1.

[0010] Preferably, the gold catalyst is 1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold; and the Lewis acid is zinc trifluoromethanesulfonate.

[0011] As a preferred embodiment, the separation and purification method in step (1) is as follows: after the reaction is completed by thin-layer chromatography, the reaction mixture is filtered through a silica gel pad and concentrated. The concentrated product is then subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain compound 3.

[0012] As a preferred embodiment, the separation and purification method in step (2) is as follows: after the reaction is completed by thin-layer chromatography, the reaction is quenched with water, the obtained organic phase is washed three times with saturated NaHSO3 aqueous solution, the obtained organic phase is concentrated, and the concentrated product is obtained by column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product molecule 4.

[0013] The beneficial effects of this invention are:

[0014] 1. This invention is the first to achieve the synthesis and characterization of bisbenzo[c,g]carbazole compounds and diene precursors.

[0015] 2. The reaction conditions of this invention are simple and the substrates are widely adaptable, making it an excellent synthetic strategy. Attached image description:

[0016] Figure 1 The 2,5-bis((Z)-1,2-diphenylvinyl)-1-methyl-1H-pyrrole prepared in Example 1 11H NMR spectrum (solvent is deuterated chloroform);

[0017] Figure 2 The 2,5-bis((Z)-1,2-diphenylvinyl)-1-methyl-1H-pyrrole prepared in Example 1 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0018] Figure 3 The 7-methyl-6,8-diphenyl-7H-dibenzo[c,g]carbazole prepared in Example 1 1 1H NMR spectrum (solvent is deuterated chloroform);

[0019] Figure 4 The 7-methyl-6,8-diphenyl-7H-dibenzo[c,g]carbazole prepared in Example 1 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0020] Figure 5 The 2,5-bis((Z)-1,2-bis(4-fluorophenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 2 1 ¹H NM spectrum (solvent is deuterated chloroform);

[0021] Figure 6 The 2,5-bis((Z)-1,2-bis(4-fluorophenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 2 19 F NMR spectrum (solvent is deuterated chloroform);

[0022] Figure 7 The 2,5-bis((Z)-1,2-bis(4-fluorophenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 2 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0023] Figure 8 The 2,12-difluoro-6,8-bis(4-fluorophenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 2 1 1H NMR spectrum (solvent is deuterated chloroform);

[0024] Figure 9 The 2,12-difluoro-6,8-bis(4-fluorophenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 2 19 F NMR spectrum (solvent is deuterated chloroform);

[0025] Figure 10 The 2,12-difluoro-6,8-bis(4-fluorophenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 213 C10 NMR spectrum (solvent is deuterated chloroform);

[0026] Figure 11 The 2,5-bis((Z)-1,2-bis(4-bromophenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 3 1 1H NMR spectrum (solvent is deuterated chloroform);

[0027] Figure 12 The 2,5-bis((Z)-1,2-bis(4-bromophenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 3 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0028] Figure 13 The 2,12-dibromo-6,8-bis(4-bromophenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 3 1 1H NMR spectrum (solvent is deuterated chloroform);

[0029] Figure 14 The 2,12-dibromo-6,8-bis(4-bromophenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 3 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0030] Figure 15 The 2,5-bis((Z)-1,2-bis(4-methylphenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 4 1 1H NMR spectrum (solvent is deuterated chloroform);

[0031] Figure 16 The 2,5-bis((Z)-1,2-bis(4-methylphenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 4 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0032] Figure 17 2,12-Dimethyl-6,8-bis(4-methylphenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 4 1 1H NMR spectrum (solvent is deuterated chloroform);

[0033] Figure 18 The 2,12-dimethyl-6,8-bis(4-methylphenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 4 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0034] Figure 19The 2,5-bis((Z)-1,2-bis(4-methoxyphenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 5 1 1H NMR spectrum (solvent is deuterated chloroform);

[0035] Figure 20 The 2,5-bis((Z)-1,2-bis(4-methoxyphenyl)vinyl)-1-methyl-1H-pyrrole prepared in Example 5 13 C10 NMR spectrum (solvent is deuterated chloroform);

[0036] Figure 21 The 2,12-dimethoxy-6,8-bis(4-methoxyphenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 5 1 1H NMR spectrum (solvent is deuterated chloroform);

[0037] Figure 22 The 2,12-dimethoxy-6,8-bis(4-methoxyphenyl)-7-methyl-7H-dibenzo[c,g]carbazole prepared in Example 5 13 C10 NMR spectrum (solvent is deuterated chloroform); Detailed implementation method:

[0038] The present invention will be further illustrated below with specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of protection of the invention. Improvements and adjustments made by those skilled in the art based on the present invention in practical applications shall still fall within the scope of protection of the present invention.

[0039] Unless otherwise specified, the equipment and reagents used in this invention are commercially available products commonly used in this technical field.

[0040] The synthetic route of this invention is as follows:

[0041]

[0042] Example 1

[0043] (1) N-methylpyrrole (compound 1, 0.2 mmol, 1.0 equivalence, 16.2 mg) and diphenylacetylene (compound 2, 0.6 mmol, 3.0 equivalence) were added to a 25 mL Shrek flask, followed by 0.03 mmol of [1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold, 0.04 mmol of zinc trifluoromethanesulfonate, and 0.1 mL of toluene solution. The resulting mixture was heated at 60 °C for 10 hours.

[0044] (2) After the reaction is completed by thin-layer chromatography analysis, the reaction mixture is filtered through a silica gel pad and concentrated.

[0045] (3) The concentrated product was subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain 2,5-bis((Z)-1,2-diphenylvinyl)-1-methyl-1H-pyrrole white solid (compound 3, 70 mg, 80%). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 1 and Figure 2 As shown. 1 H NMR(400MHz, CDCl3)δ7.49(d,J=7.3Hz,4H),7.35(t,J=7.4Hz,4H),7.32–7.21( m,6H),7.19(d,J=7.1Hz,2H),7.12(d,J=7.3Hz,6H),6.14(s,2H),2.78(s,3H). 13 C NMR (101MHz, CDCl3) δ142.3,137.5,133.3,131.7,130.6,129.0,128.3,128.2,127.7,127.3,126.9,110.0,31.3.

[0046] (4) I2 (0.2 mmol, 1.0 equivalence, 50.7 mg) was added to a 20 mL solution of compound 3 (0.2 mmol, 1.0 equivalence) in cyclohexane under 395 nm UV irradiation. The reaction mixture was stirred at room temperature for 6 hours.

[0047] (5) After the reaction is complete, quench the reaction with 20 ml of water and wash the organic phase three times with saturated NaHSO3 (aqueous solution).

[0048] (6) The concentrated product was subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product, 7-methyl-6,8-diphenyl-7H-dibenzo[c,g]carbazole, as a white solid (compound 4.78 mg, 90% yield). 1 HNMR spectrum and 13 The C NMR spectra are as follows: Figure 3 and Figure 4 As shown. 1 H NMR (400MHz, CDCl3) δ9.25 (d, J = 8.5Hz, 2H), 8.06 (d, J = 7.1Hz, 2H), 7.81 (s, 2H), 7.71 (t, J = 7.0Hz, 2H),7.67–7.62(m,4H),7.58(t,J=7.4Hz,2H),7.54–7.48(m,4H),7.47–7.41(m,2H),3.05(s,3H). 13C NMR (101MHz, CDCl3) δ140.7,138.6,129.5,129.3,128.9,128.7,128.3,128.2,128.0,127.3,125.1,125.0,123.7,119.0,38.8.

[0049] Example 2

[0050] (1) N-methylpyrrole (compound 1, 0.2 mmol, 1.0 equivalence, 16.2 mg) and 1,2-bis(4-fluorophenyl)yne (compound 2, 0.6 mmol, 3.0 equivalence) were added to a 25 mL Shrek flask, followed by 0.03 mmol of [1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold, 0.04 mmol of zinc trifluoromethanesulfonate, and 0.1 mL of toluene solution. The resulting mixture was heated at 60 °C for 10 hours.

[0051] (2) After the reaction is completed by thin-layer chromatography analysis, the reaction mixture is filtered through a silica gel pad and concentrated.

[0052] (3) The concentrated product was analyzed by column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain 2,5-bis((Z)-1,2-bis(4-fluorophenyl)vinyl)-1-methyl-1H-pyrrole white solid (compound 3, 66 mg, 65%). 1 H NMR spectrum 19 F NMR spectrum and 13 The C NMR spectra are as follows: Figure 5 , Figure 6 and Figure 7 As shown. 1 H NMR (400MHz, CDCl3) δ7.45–7.37(m,4H),7.05(dd,J=11.2,5.4Hz,8H),7.01(s,2H),6.93(t,J=8.4Hz,4H),6.13(s,2H),2.76(s,3H). 19 F NMR (377MHz, CDCl3) δ-113.3,-114.2. 13C NMR (101MHz, CDCl3) δ162.6 (d, J = 248.0Hz), 161.8 (d, J = 248.6Hz), 138.2 (d, J = 3.2Hz), 133.5 (d, J = 3.4Hz), 132 .0,131.5,130.6(d,J=7.8Hz),129.2,128.4(d,J=8.0Hz),115.3(d,J=7.6Hz),115.1(d,J=7.3Hz),110.4,31.3.

[0053] (4) I2 (0.2 mmol, 1.0 equivalence, 50.7 mg) was added to a 20 mL solution of compound 3 (0.2 mmol, 1.0 equivalence) in cyclohexane under 395 nm UV irradiation. The reaction mixture was stirred at room temperature for 6 hours.

[0054] (5) After the reaction is complete, quench the reaction with 20 ml of water and wash the organic phase three times with saturated NaHSO3 (aqueous solution).

[0055] (6) The concentrated product was subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product, 2,12-difluoro-6,8-bis(4-fluorophenyl)-7-methyl-7H-dibenzo[c,g]carbazole, as a white solid (compound 4,86 ​​mg, 85% yield). 1 H NMR spectrum 19 F NMR spectrum and 13 The C NMR spectra are as follows: Figure 8 , Figure 9 and Figure 10 As shown. 1 HNMR(400MHz, CDCl3) δ8.69(d,J=11.6Hz,2H),7.98(dd,J=8.8,6.2Hz,2H),7.71(s,2H),7. 53(dd,J=8.4,5.4Hz,4H),7.30(td,J=8.6,2.2Hz,2H),7.18(t,J=8.6Hz,4H),3.00(s,3H). 19 F NMR (377MHz, CDCl3) δ-112.6,-114.4. 13C NMR (101MHz, CDCl3) δ162.4 (d, J = 247.2Hz), 160.5 (d, J = 245.6Hz), 139.0, 136.3 (d, J = 3.5Hz), 131.1 (d, J = 9.4Hz), 130.8 (d, J = 8.0Hz) ,129.0,128.8,126.4,126.1(d,J=2.5Hz),118.7(d,J=4.5Hz),115.4(d,J=21.4Hz),113.7(d,J=24.6Hz),109.3(d,J=23.2Hz),38.7.

[0056] Example 3

[0057] (1) N-methylpyrrole (compound 1, 0.2 mmol, 1.0 equivalence, 16.2 mg) and 1,2-bis(4-bromophenyl)yne (compound 2, 0.6 mmol, 3.0 equivalence) were added to a 25 mL Shrek flask, followed by 0.03 mmol of [1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold, 0.04 mmol of zinc trifluoromethanesulfonate, and 0.1 mL of toluene solution. The resulting mixture was heated at 60 °C for 10 hours.

[0058] (2) After the reaction is completed by thin-layer chromatography analysis, the reaction mixture is filtered through a silica gel pad and concentrated.

[0059] (3) The concentrated product was analyzed by column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain 2,5-bis((Z)-1,2-bis(4-bromophenyl)vinyl)-1-methyl-1H-pyrrole white solid (compound 3, 102.4 mg, 68%). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 11 and Figure 12 As shown. 1 H NMR (400MHz, CDCl3) δ7.45–7.37(m,4H),7.05(dd,J=11.2,5.4Hz,8H),7.01(s,2H),6.93(t,J=8.4Hz,4H),6.13(s,2H),2.76(s,3H). 19 F NMR (377MHz, CDCl3) δ-113.3,-114.2. 13C NMR (101MHz, CDCl3) δ162.6 (d, J = 248.0Hz), 161.8 (d, J = 248.6Hz), 138.2 (d, J = 3.2Hz), 133.5 (d, J = 3.4Hz), 132 .0,131.5,130.6(d,J=7.8Hz),129.2,128.4(d,J=8.0Hz),115.3(d,J=7.6Hz),115.1(d,J=7.3Hz),110.4,31.3.

[0060] (4) I2 (0.2 mmol, 1.0 equivalence, 50.7 mg) was added to a 20 mL solution of compound 3 (0.2 mmol, 1.0 equivalence) in cyclohexane under 395 nm UV irradiation. The reaction mixture was stirred at room temperature for 6 hours.

[0061] (5) After the reaction is complete, quench the reaction with 20 ml of water and wash the organic phase three times with saturated NaHSO3 (aqueous solution).

[0062] (6) The concentrated product was subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product, 2,12-dibromo-6,8-bis(4-bromophenyl)-7-methyl-7H-dibenzo[c,g]carbazole, as a white solid (compound 4, 124.4 mg, 83% yield). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 13 and Figure 14 As shown. 1 H NMR (400MHz, CDCl3) δ9.26 (s, 2H), 7.85 (d, J = 8.6 Hz, 2H), 7.67 (s, 2H), 7.62 (d, J = 8.2 Hz, 6H), 7.44 (d, J = 8.2 Hz, 4H), 3.01 (s, 3H). 13 C NMR (101MHz, CDCl3) δ139.1,138.9,131.7,130.8,130.4,129.2,128.9,127.9,127.4,127.2,127.0,122.0,120.0,118.2,39.1.

[0063] Example 4

[0064] (1) N-methylpyrrole (compound 1, 0.2 mmol, 1.0 equivalence, 16.2 mg) and 1,2-bis(4-methylphenyl)yne (compound 2, 0.6 mmol, 3.0 equivalence) were added to a 25 mL Shrek flask, followed by 0.03 mmol of [1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold, 0.04 mmol of zinc trifluoromethanesulfonate, and 0.1 mL of toluene solution. The resulting mixture was heated at 60 °C for 10 hours.

[0065] (2) After the reaction is completed by thin-layer chromatography analysis, the reaction mixture is filtered through a silica gel pad and concentrated.

[0066] (3) The concentrated product was analyzed by column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain 2,5-bis((Z)-1,2-bis(4-methylphenyl)vinyl)-1-methyl-1H-pyrrole white solid (compound 3, 69.1 mg, 70%). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 15 and Figure 16 As shown. 1 H NMR (400MHz, CDCl3) δ7.43(d,J=8.1Hz,4H),7.19(d,J=8.0Hz,4H),7.08(d,J=8.5H z, 6H), 7.02 (d, J = 8.0Hz, 4H), 6.15 (s, 2H), 2.81 (s, 3H), 2.41 (s, 6H), 2.36 (s, 6H). 13 C NMR (101MHz, CDCl3) δ139.7,137.3,136.9,134.8,132.3,131.8,129.7,129.0,128.93,128.89,126.8,109.6,31.2,21.3,21.1.

[0067] (4) I2 (0.2 mmol, 1.0 equivalence, 50.7 mg) was added to a 20 mL solution of compound 3 (0.2 mmol, 1.0 equivalence) in cyclohexane under 395 nm UV irradiation. The reaction mixture was stirred at room temperature for 6 hours.

[0068] (5) After the reaction is complete, quench the reaction with 20 ml of water and wash the organic phase three times with saturated NaHSO3 (aqueous solution).

[0069] (6) The concentrated product was subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product, 2,12-dimethyl-6,8-bis(4-methylphenyl)-7-methyl-7H-dibenzo[c,g]carbazole, as a white solid (Compound 4, 85.2 mg, 87% yield). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 17 and Figure 18 As shown. 1 H NMR (400MHz, CDCl3) δ9.05 (s, 2H), 7.92 (d, J = 8.2Hz, 2H), 7.71 (s, 2H), 7.50 (d, J = 7.9Hz, 4H),7.38(d,J=8.0Hz,2H),7.29(d,J=7.8Hz,4H),3.05(s,3H),2.69(s,6H),2.45(s,6H). 13 CNMR(101MHz, CDCl3)δ139.0,138.0,136.8,134.4,129.2,128.9,128.49,128.47,128.3,127.7,127.2,125.5,124.9,118.7,38.7,22.1,21.2.

[0070] Example 5

[0071] (1) N-methylpyrrole (compound 1, 0.2 mmol, 1.0 equivalence, 16.2 mg) and 1,2-bis(4-methoxyphenyl)yne (compound 2, 0.6 mmol, 3.0 equivalence) were added to a 25 mL Shrek flask, followed by 0.03 mmol of [1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold, 0.04 mmol of zinc trifluoromethanesulfonate, and 0.1 mL of toluene solution. The resulting mixture was heated at 60 °C for 10 hours.

[0072] (2) After the reaction is completed by thin-layer chromatography analysis, the reaction mixture is filtered through a silica gel pad and concentrated.

[0073] (3) The concentrated product was analyzed by column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain 2,5-bis((Z)-1,2-bis(4-methoxyphenyl)vinyl)-1-methyl-1H-pyrrole white solid (compound 3, 81.4 mg, 73%). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 19 and Figure 20 As shown. 1H NMR(400MHz, CDCl3)δ7.47(d,J=8.5Hz,4H),7.10–6.98(m,6H),6.93(d,J=8.6Hz ,4H),6.82(d,J=8.6Hz,4H),6.19(s,2H),3.87(s,6H),3.83(s,6H),2.84(s,3H). 13 C NMR (101MHz, CDCl3) δ159.1,158.5,135.2,131.8,130.8,130.5,130.1,128.4,127.8,113.60,113.57,109.6,55.3,55.1,31.0.

[0074] (4) I2 (0.2 mmol, 1.0 equivalence, 50.7 mg) was added to a 20 mL solution of compound 3 (0.2 mmol, 1.0 equivalence) in cyclohexane under 395 nm UV irradiation. The reaction mixture was stirred at room temperature for 6 hours.

[0075] (5) After the reaction is complete, quench the reaction with 20 ml of water and wash the organic phase three times with saturated NaHSO3 (aqueous solution).

[0076] (6) The concentrated product was subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product, 2,12-dimethyl-6,8-bis(4-methoxyphenyl)-7-methyl-7H-dibenzo[c,g]carbazole, as a white solid (Compound 4, 98.6 mg, 89% yield). 1 H NMR spectrum and 13 The C NMR spectra are as follows: Figure 21 and Figure 22 As shown. 1 H NMR (400MHz, CDCl3) δ8.48(s,2H),7.93(d,J=8.9Hz,2H),7.68(s,2H),7.50(d,J=8.6Hz,4H) ,7.20(dd,J=8.8,1.9Hz,2H),7.00(d,J=8.6Hz,4H),4.00(s,6H),3.88(s,6H),3.04(s,3H). 13 C NMR (101MHz, CDCl3) δ158.9,157.1,139.3,133.2,130.4,130.2,129.1,128.3,125.4,124.7,118.4,114.7,113.7,106.4,55.6,55.3,38.5.

[0077] The foregoing detailed description is a specific illustration of one possible embodiment of the present invention, and this embodiment is not intended to limit the scope of the invention.

[0078] All equivalent implementations or modifications made without departing from the scope of this invention shall be included within the scope of this patent.

Claims

1. A method for the gold-photocatalyzed synthesis of benzo[c,g]carbazole compounds, the synthetic route being as follows: , Where R 1 R 2 Simultaneously selected from one of 4-methoxy, 4-methyl, 4-bromo, 4-fluoro, and hydrogen; the synthetic method includes the following steps: (1) Add a gold catalyst and a Lewis acid catalyst to a mixed toluene solution of compound 1 and compound 2, and react the resulting reaction solution at 60°C for 10 h. After the reaction is complete, separate and purify to obtain compound 3; compound 1 is N-methylpyrrole; compound 2 is a diphenylacetylene compound; the ratio of compound 1, compound 2, gold catalyst and Lewis acid is 1:3:0.15:0.2; (2) Dissolve compound 3 obtained in step (1) in cyclohexane, add I2 to the resulting solution under ultraviolet light, stir for 6 hours at room temperature, and after the reaction is completed, separate and purify to obtain compound 4, namely benzo[c,g]carbazole compound; the molar ratio of compound 3 to I2 is 1:1; The gold catalyst is 1,3-bis(2,6-diisopropylphenyl)imidazol-2-yl][bis(trifluoromethanesulfonylimide)]gold; the Lewis acid is zinc trifluoromethanesulfonate.

2. The method for synthesizing benzo[c,g]carbazole compounds by gold-photocatalytic synergistic catalysis according to claim 1, characterized in that, The separation and purification method described in step (1) is as follows: after the reaction is completed by thin-layer chromatography, the reaction mixture is filtered through a silica gel pad and concentrated. The concentrated product is then subjected to column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain compound 3.

3. The method for synthesizing benzo[c,g]carbazole compounds by gold-photocatalytic synergistic catalysis according to claim 1, characterized in that, The separation and purification method described in step (2) is as follows: after the reaction is completed by thin-layer chromatography, the reaction is quenched with water, the obtained organic phase is washed three times with saturated NaHSO3 aqueous solution, the obtained organic phase is concentrated, and the obtained concentrated product is obtained by column chromatography using a mixture of petroleum ether and diethyl ether as the developing solvent to obtain the target product molecule 4.

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