A method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole

Abstract

This invention relates to the field of compound synthesis technology, specifically disclosing a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole. The method of this invention generates the target compound in one step through a catalytic coupling reaction of compound 1 with p-bromoaniline. This method utilizes inexpensive raw materials, significantly reducing production costs; it also features a short reaction time, mild reaction conditions, and simple process operation; the post-reaction processing is convenient, and high-purity products are easily obtained, making it suitable for large-scale production.

Description

Technical Field

[0001] This invention relates to the field of compound synthesis technology, and in particular to a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole. Background Technology

[0002] 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole, with the following structural formula:

[0003] .

[0004] 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole compounds and their derivatives are a class of very important pharmaceutical and optoelectronic material intermediates, and are key core structures frequently used in drug and optoelectronic material research and development. However, current synthetic methods are limited, and the reaction steps are lengthy or the raw materials are expensive. Furthermore, most of the reported methods currently use stepwise coupling methods for synthesis, which significantly increases production costs and the difficulty of product purification due to the repeated use of catalysts and ligands.

[0005] Given the current situation, there is an urgent need to develop better synthetic routes and new synthetic methods for 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole compounds, which is of great significance for realizing their industrial production. Summary of the Invention

[0006] The main technical problem solved by this invention is to provide a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole, involving the following reaction formula:

[0008] ;

[0009] The synthesis method includes the following steps:

[0010] (1) Mix compound 1 with solvent, add catalyst and ligand compound under inert atmosphere, then heat to 50-60℃ and stir for 20-60 minutes to obtain reaction system 1;

[0011] (2) Cool the reaction system 1 to 15-35℃, add p-bromoaniline and base, then heat to 70-80℃, stir for 1-5 hours, then heat to 90-105℃, continue stirring for 8-10 hours to prepare the target compound.

[0012] In one embodiment of the present invention, the solvent is selected from at least one of 1,4-dioxane and toluene.

[0013] In one embodiment of the present invention, the catalyst is palladium acetate.

[0014] In one embodiment of the present invention, the ligand compound is BINAP (1,1'-binaphthyl-2,2'-bisdiphenylphosphine).

[0015] In one embodiment of the present invention, the alkali is sodium tert-butoxide or potassium tert-butoxide.

[0016] As one embodiment of the present invention, the molar ratio of compound 1, catalyst, and ligand compound is: compound 1: catalyst: ligand compound = 1: (0.01~0.05): (0.01~0.1).

[0017] In one embodiment of the present invention, the molar ratio of p-bromoaniline to compound 1 is: compound 1: p-bromoaniline = 1: (1-2).

[0018] In one embodiment of the present invention, the molar ratio of the alkali to the compound 1 is: compound 1: alkali = 1: (2-3).

[0019] The present invention provides a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole, which generates the target compound in one step through a catalytic coupling reaction of binaphthyl dibromo (i.e., compound 1) and p-bromoaniline. The method of the present invention utilizes inexpensive raw materials, significantly reducing production costs; it also features a short reaction time, mild reaction conditions, and simple process operation; the post-reaction processing is simple, and high-purity products are easily obtained, making it suitable for large-scale production.

[0020] In the preparation of 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole, the method of the present invention prevents the formation of double coupling products by selecting and controlling the reaction conditions. After the first bromine of the reaction substrate undergoes a coupling reaction with p-bromoaniline, a further intramolecular coupling reaction immediately occurs to obtain the target product. Attached Figure Description

[0021] Figure 1 It is the 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole prepared in Example 1 of this invention. 1 H-NMR spectrum. Detailed Implementation

[0022] The technical solution of the present invention will be described in detail below through specific embodiments. These embodiments are intended to further illustrate the content of the present invention, but are not intended to limit the scope of protection of the claims of the present invention.

[0023] Unless otherwise specified, the pharmaceutical agents used in the following embodiments are all commercially available products.

[0024] The technical solution of the present invention will be described below with reference to specific embodiments.

[0025] Example 1

[0026] This embodiment provides a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole, the reaction formula of which is:

[0027] ;

[0028] The synthesis method includes the following steps:

[0029] (1) Compound 1 (4.12 g, 0.01 mol) was mixed with 1,4-dioxane (100 mL), and the catalyst palladium acetate (22.4 mg, 0.0001 mol) and the ligand compound BINAP (124.4 mg, 0.0002 mol) were added under a nitrogen inert atmosphere. The mixture was then heated to 50 °C and stirred for 60 minutes to obtain reaction system 1.

[0030] (2) Cool reaction system 1 to room temperature (25℃), add p-bromoaniline (1.89g, 0.011mol) and sodium tert-butoxide (1.92g, 0.02mol), then heat to 70℃ and stir for 2 hours, then heat to 100℃ and continue stirring for 10 hours, then stop the reaction;

[0031] The reaction system was cooled to room temperature and filtered. 50g of silica gel was added to the filtration funnel before filtration. The filtrate obtained from the first filtration was filtered again. The filtrate from the second filtration was collected, evaporated to dryness, and the residue was recrystallized from ethanol / water (v / v=1:10) to obtain 3.98g of product, which was identified as 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole compound, with a product yield of 94.3%.

[0032] Nuclear magnetic resonance analysis of the product prepared in this embodiment 1 H-NMR spectrum as follows Figure 1 As shown, LCMS analysis indicates the product purity is greater than 98%.

[0033] Example 2

[0034] This embodiment provides a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole. The reaction formula is the same as in Example 1, and the synthesis method includes the following steps:

[0035] (1) Compound 1 (4.12 g, 0.01 mol) was mixed with toluene (100 mL), and the catalyst palladium acetate (22.4 mg, 0.0001 mol) and the ligand compound BINAP (124.4 mg, 0.0002 mol) were added under a nitrogen inert atmosphere. The mixture was then heated to 60 °C and stirred for 30 minutes to obtain reaction system 1.

[0036] (2) Cool reaction system 1 to room temperature (25℃), add p-bromoaniline (1.89g, 0.011mol) and sodium tert-butoxide (1.92g, 0.02mol), then heat to 80℃ and stir for 3 hours, then heat to 105℃ and continue stirring for 8 hours, then stop the reaction;

[0037] The reaction system was cooled to room temperature and filtered. 50g of silica gel was added to the filtration funnel before filtration. The filtrate obtained from the first filtration was filtered again. The filtrate from the second filtration was collected, evaporated to dryness, and the residue was recrystallized from ethanol / water (v / v=1:10) to obtain 3.87g of product, which was identified as 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole compound, with a product yield of 91.7%.

[0038] Example 3

[0039] This embodiment provides a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole. The reaction formula is the same as in Example 1, and the synthesis method includes the following steps:

[0040] (1) Compound 1 (4.12 g, 0.01 mol) was mixed with 1,4-dioxane (100 mL), and the catalyst palladium acetate (67.2 mg, 0.0003 mol) and the ligand compound BINAP (373.2 mg, 0.0006 mol) were added under a nitrogen inert atmosphere. The mixture was then heated to 50 °C and stirred for 60 minutes to obtain reaction system 1.

[0041] (2) Cool reaction system 1 to room temperature (25℃), add p-bromoaniline (1.89g, 0.011mol) and sodium tert-butoxide (1.92g, 0.02mol), then heat to 70℃ and stir for 2 hours, then heat to 100℃ and continue stirring for 10 hours, then stop the reaction;

[0042] The reaction system was cooled to room temperature and filtered. 50g of silica gel was added to the filtration funnel before filtration. The filtrate obtained from the first filtration was filtered again. The filtrate from the second filtration was collected, evaporated to dryness, and the residue was recrystallized from ethanol / water (v / v=1:10) to obtain 3.91g of product, which was identified as 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole compound, with a product yield of 92.7%.

[0043] Example 4

[0044] This embodiment provides a method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole. The reaction formula is the same as in Example 1, and the synthesis method includes the following steps:

[0045] (1) Compound 1 (4.12 g, 0.01 mol) was mixed with 1,4-dioxane (100 mL), and the catalyst palladium acetate (22.4 mg, 0.0001 mol) and the ligand compound BINAP (124.4 mg, 0.0002 mol) were added under a nitrogen inert atmosphere. The mixture was then heated to 50 °C and stirred for 60 minutes to obtain reaction system 1.

[0046] (2) Cool reaction system 1 to room temperature (25℃), add p-bromoaniline (3.44g, 0.02mol) and sodium tert-butoxide (2.88g, 0.03mol), then heat to 70℃ and stir for 2 hours, then heat to 100℃ and continue stirring for 10 hours, then stop the reaction;

[0047] The reaction system was cooled to room temperature and filtered. 50g of silica gel was added to the filtration funnel before filtration. The filtrate obtained from the first filtration was filtered again. The filtrate from the second filtration was collected, evaporated to dryness, and the residue was recrystallized from ethanol / water (v / v=1:10) to obtain 3.94g of product, which was identified as 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole compound, with a product yield of 93.4%.

[0048] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for synthesizing 7-(4-bromophenyl)-7H-dibenzo[c,g]carbazole, characterized in that, The reaction formulas involved are: ； The synthesis method includes the following steps: (1) Mix compound 1 with solvent, add catalyst and ligand compound under inert atmosphere, then heat to 50-60℃ and stir for 20-60 minutes to obtain reaction system 1; (2) Cool the reaction system 1 to 15-35℃, add p-bromoaniline and base, then heat to 70-80℃, stir for 1-5 hours, then heat to 90-105℃, continue stirring for 8-10 hours to prepare the target compound.

2. The method according to claim 1, characterized in that, The solvent is selected from at least one of 1,4-dioxane and toluene.

3. The method according to claim 1, characterized in that, The catalyst is palladium acetate.

4. The method according to claim 1, characterized in that, The ligand compound is BINAP.

5. The method according to claim 1, characterized in that, The alkali is sodium tert-butoxide or potassium tert-butoxide.

6. The method according to claim 1, characterized in that, The molar ratio of compound 1, catalyst, and ligand compound is: compound 1: catalyst: ligand compound = 1: (0.01~0.05): (0.01~0.1).

7. The method according to claim 1, characterized in that, The molar ratio of p-bromoaniline to compound 1 is: compound 1: p-bromoaniline = 1: (1-2).

8. The method according to claim 1, characterized in that, The molar ratio of the alkali to the compound 1 is: compound 1: alkali = 1: (2-3).

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