Benzoquinolizine acridine compound as well as preparation method and application thereof

Abstract

The invention discloses a benzoquinolizine acridine compound as well as a preparation method and application thereof, the synthetic route is as follows: the synthetic method belongs to a novel synthetic method of a compound 4, and the blank state of chemical synthesis of the compound 4 is solved. The compound 4 and derivatives and analogues thereof have wide application in the aspects of photoelectric functional materials, fluorescent probes / sensing materials, biological activity / medicinal chemistry and the like.

Description

Technical Field

[0001] This invention relates to the field of compound preparation, specifically to a benzoquinazine-acridine compound, its preparation method, and its application. Background Technology

[0002] Compounds containing the "benzo-quinolizino-acridine" structure belong structurally to the family of "strongly conjugated polycyclic heteroaromatics / plate-like aromatic heterocycles" (with more aromatic rings fused to the acridine skeleton and containing bridging substructures), and therefore are expected to have strong violet-visible absorption and fluorescence / luminescence potential (as seen in reports of similar structures). These compounds are mainly used in the following research fields.

[0003] 1. Optoelectronic functional materials: Used to construct bridged / three-dimensional conjugated chromophores (bridged triphenylamine / 3DD-π-A sensitizers / star molecules) for research in organic optoelectronic devices, dye-sensitized systems, and color-tunable luminescent materials (adjusting spectra, energy levels, and device performance). Specific examples can be found in the work on using such cores for three-dimensional D-π-A sensitizers and hue-tunable references. (Dyes and Pigments 2017, 140, 278-285. Three-dimensional D-π-A organic sensitizer with coplanar triphenylamine moiety for dye-sensitized solar cells)

[0004]

[0005] 2. Fluorescent Probes / Sensing Materials: Derivatives containing this type of structure have been reported for use as fluorescent probes / optically responsive molecules (e.g., certain bridging derivatives used in probe and sensor research), because the rigidity and extended conjugation of the framework often bring considerable optical properties. Recent reports have covered the application of "bridged triphenylamine-based fluorescent probes" and related Knoevenagel-type functionalization steps. (Bioorganic Chemistry 2024, 152, 107742. Bridged triphenylamine-based fluorescent probe for selective and direct detection of HSA)

[0006] 3. Potential areas of interest in bioactivity / medicinal chemistry: Historically, acridine and its derivatives have been important in medicinal chemistry (numerous reports exist on their activities as DNA intercalators, antitumor, antibacterial, and antiparasitic agents); therefore, derivatives containing larger / fused acridine cores are often screened or designed as potential bioactive molecules (e.g., as DNA intercalators, enzyme inhibitory lead fragments, or fluorescently labeled molecules). (RSCAdv.2017,7,15776-15804. Recent developments in the synthesis and biological activity of acridine / acridone analogues.)

[0007]

[0008] To date, some progress has been made in the chemical synthesis of this type of compound. The following is a list of representative references related to the synthesis of this skeleton or closely related derivatives that can be found in the literature and literature reviews.

[0009] 1. Zou,SNet al.,Org.Lett.2021,23,958-962.Fully BridgedTriphenylamine DerivativesasColor-TunableThermallyActivatedDelayedFluorescenceEmitters.

[0010] Key points: The report describes “fully bridged triphenylamine derivatives”, including the construction of tunable luminescent / optical properties using a benzo[1,9]quinolizino-acridine-type core; synthetic strategies and functionalization methods containing such cores are available for reference (aromatic coupling, cyclization and bridging steps).

[0011]

[0012] 2. Zhao, DX et al., Dyes and Pigments 2017, 140, 278-285. Three-dimensional D-π-Aorganic sensitizer with coplanar triphenylamine moiety fordye-sensitized solar cells.

[0013] Key points: This work discusses the use of 8,12-dihydro-benzo[1,9]quinolizino-acridine cores or their derivatives in the construction of 3D sensitizer / donor units, and their synthesis and photoelectric properties in dye / solar devices. This type of work includes key reaction conditions related to core construction.

[0014]

[0015] 3. Deng, YDet al., Bioorganic Chemistry 2024, 152, 107742. Bridged triphenylamine-based fluorescent probe for selective and direct detection of HAS.

[0016] Key points: The hexamethyl-substituted 8,12-dihydro-4H-benzo[1,9]quinolizino[...]acridine skeleton was used in the fluorescent probe study. The article provides application examples of subsequent functionalization methods such as Knoevenagel condensation, which can serve as a reference for modification and functionalization.

[0017]

[0018] 4. ResearchGate review, RSCAdv.2019,9,16606-16682.Anoverviewonsyntheticstrategies for the constructionofstar-shapedmolecules."SynthesisofSSM-450withwith benzo[9,1]qui-nolizino[3,4,5,6,7-defg]acridinecore".

[0019] Key takeaways: This review summarizes several strategies for constructing such cores (for building star-shaped / bridged molecules) and shows synthetic fragments and key intermediates for specific molecules such as SSM-450, which can help design synthetic routes or find similar precursors.

[0020]

[0021] Based on the above reports, compounds with benzo-quinolizino-acridine-like structures have a wide range of applications. Unfortunately, the methods for synthesizing the cores of these compounds are currently very limited, so it is essential to develop an effective synthetic method. Summary of the Invention

[0022] To address the deficiencies in existing technologies, this invention provides a four-step method for the synthesis and application of benzoquinazine-acridine compounds. The method involves Ullman coupling and subsequent internal cyclization / reduction conditions; the reduction conditions for the final formation of these compounds have not been previously reported.

[0023] This invention first provides a method for preparing benzoquinazine-acridine compounds, the synthetic route of which is as follows:

[0024]

[0025] The preparation steps are as follows:

[0026] S1 dissolves methyl anthranilate, methyl 2-halobenzoate, base, Cu, and CuX in solvent 1, heats to 120-250°C, and reacts for 6-144 hours; removes solvent under reduced pressure, purifies the residue, and gives compound 1.

[0027] S2 dissolves compound 1 and a base in solvent 2 and refluxes for 2-48 hours. After hydrolysis, the mixture is cooled to room temperature, concentrated, acidified with concentrated hydrochloric acid, filtered under reduced pressure to obtain the solid, and washed with water. The filter residue is dried overnight to obtain compound 2.

[0028] S3 mixed compound 2, SOCl2 and DMF in anhydrous CH2Cl2 at 20-50°C for 3-24 hours; then Lewis acid was added and stirred at 20-50°C for 1-48 hours. The precipitate was filtered off and stirred in an aqueous alkaline solution for 5-60 minutes. After filtration, the residue was washed with excess water and organic solvent and dried to obtain compound 3.

[0029] S4 dissolves compound 3 in solvent 3; under nitrogen protection, a solution containing borane is added dropwise at 0°C; then the reaction mixture is stirred at 30-100°C for 3-48 hours; after the reaction is complete, the reaction solution is cooled to room temperature; water is slowly added dropwise to the solution, then an aqueous solution of alkali is added, and the mixture is stirred for 5-60 minutes; the solid is obtained by filtration and washed several times with water or other organic solvents; the obtained solid is dried to obtain compound 4.

[0030] Preferably, in step S1, the alkali is one or more of K3PO4, Na2CO3, K2CO3 or Cs2CO3.

[0031] The term "one or more" in this invention refers to a single type, two types, or more types.

[0032] Preferably, in step S1, CuX is a copper halide.

[0033] Preferably, in step S1, the solvent 1 is one or more of DMSO, DMF, NMP, THF, toluene, or diphenyl ether.

[0034] Preferably, in step S2, the alkali is one or more of LiOH, NaOH, or KOH.

[0035] Preferably, in step S2, the solvent 2 is one or more of methanol, ethanol, acetonitrile, or tetrahydrofuran.

[0036] Preferably, in step S2, the volume ratio of compound 1 and base to solvent 2 is 1-10:1-10.

[0037] Preferably, in step S3, the Lewis acid is one or more of SnCl4, TiCl4, or Et2O.BF3.

[0038] Preferably, in step S3, the alkali is one or more of NaOH, KOH, Na2CO3, or NaHCO3.

[0039] The present invention also provides a benzoquinazine-acrylidine compound, which is prepared by the above-described method for preparing benzoquinazine-acrylidine compounds.

[0040] This invention also provides an application of benzoquinazine-acridine compounds, which can be used as a core in optoelectronic functional materials, and can also be used in the preparation of optoelectronic functional materials.

[0041] The beneficial effects of this invention are:

[0042] 1. The entire synthetic route uses inexpensive and readily available raw materials and reagents, does not involve expensive noble metal-catalyzed coupling reactions, and has a short reaction route (only 4 steps). It is formed through Ullman coupling and subsequent internal cyclization / reduction conditions. The reduction conditions for the final step to generate this type of compound have not yet been reported. Except for the first step reaction (which requires a high temperature of around 200 degrees Celsius), the conversion rates are moderate to high, the post-processing is easy, purification is simple, and it is suitable for scale-up reactions.

[0043] 2. Compound 4 and its derivatives and analogs have extremely wide applications in optoelectronic functional materials, fluorescent probes / sensing materials, and bioactive / medicinal chemistry.

[0044] 3. Compound 4 and its derivatives and analogs interact with fluorescent substances, causing differences in charge distribution in their molecules, resulting in changes in the length of CN bonds and alterations in symmetry. This leads to changes in paramagnetic or diamagnetic self-selection in the molecules, causing a series of unique changes in fluorescence properties and biological / pharmaceutical properties. It can be used as a core framework material for high-emission TANGO solids, nitrogen-doped aza-triangulene, and non-covalent through-space conjugated (TSC) emitters. Attached Figure Description

[0045] Appendix Figure 1 The image shows the 1H-NMR spectrum (400MHz, DMSO-d6) of compound 1 in Example 1.

[0046] Appendix Figure 2 The image shows the 1H-NMR spectrum (400MHz, DMSO-d6) of compound 2 from Example 1.

[0047] Appendix Figure 3 The image shows the 1H-NMR spectrum (400MHz, CDCl3+TFA) of compound 3 in Example 1.

[0048] Appendix Figure 4 The image shows the 1H-NMR spectrum (400MHz, CDCl3) of compound 4 from Example 1.

[0049] Appendix Figure 5 The image shows the 13C-NMR spectrum (100MHz, CDCl3) of compound 4 from Example 1.

[0050] Appendix Figure 6 The HPLC spectrum (254 nm) of compound 4 from Example 1 is shown. Detailed Implementation

[0051] To enable those skilled in the art to better understand the technical solution of the invention, the invention will be further described in detail below with reference to specific embodiments.

[0052] This invention first provides a method for preparing benzoquinazine-acridine compounds, the synthetic route of which is as follows:

[0053]

[0054] More preferably, the synthesis process conditions are as follows:

[0055]

[0056] The preparation steps are as follows:

[0057] S1 dissolves methyl anthranilate, methyl 2-halobenzoate, a base, Cu, and CuX in solvent 1, heats to 120-250°C, and reacts for 6-144 hours; solvent 1 is removed under reduced pressure, and the residue is purified to obtain compound 1; preferably, methyl 2-halobenzoate is methyl 2-iodobenzoate, CuX is CuI, the heating temperature is preferably 190°C, and the reaction time is preferably 72 hours. Solvent 1 is preferably diphenyl ether.

[0058] The specific procedure is as follows: Methyl anthranilate, methyl 2-halobenzoate, base, Cu, and CuX are dissolved in solvent 1 (DMSO, DMF, NMP, THF, toluene, or diphenyl ether), and heated to 120 to 250°C under N2 protection for 6 to 144 hours. Solvent 1 is removed under reduced pressure, and the residue is purified by silica gel column chromatography to obtain compound 1.

[0059] The Ullman coupling reaction catalyzed by copper reagent in step S1 requires an anhydrous and oxygen-free environment, and the reaction temperature is preferably close to 200°C. The long reaction time also prevents the reaction from easily reaching the endpoint, allowing for a more complete reaction. The halogenated product is preferably an iodide, which has the highest reactivity, as the substrate. This minimizes side reactions and allows for the recovery of starting materials and intermediates for subsequent reactions.

[0060] S2 dissolves compound 1 and the base in solvent 2 and refluxes for 2-48 hours. After hydrolysis, the mixture is cooled to room temperature, concentrated, and acidified with concentrated hydrochloric acid. The precipitated solid is filtered under reduced pressure and washed with water. The filter residue is dried overnight to obtain compound 2. Preferably, the base is sodium hydroxide, the solvent 2 is ethanol, and the mixture is refluxed for 16 hours.

[0061] The specific procedure is as follows: In a round-bottom flask, compound 1 and a base (LiOH, NaOH, or KOH) are dissolved in an aqueous solution of solvent 2 (methanol, ethanol, acetonitrile, or tetrahydrofuran) (volume ratio 1:10 to 10:1), and the mixture is refluxed for 2 to 48 hours. After hydrolysis, the mixture is cooled to room temperature, the reaction system is concentrated to half its volume, then acidified with concentrated hydrochloric acid, and the precipitated solid compound 2 is filtered under reduced pressure and washed with plenty of water. The filter residue is dried overnight in a vacuum drying oven at 45°C to obtain solid compound 2.

[0062] In step S2, it is important to monitor the reaction endpoint during the ester hydrolysis reaction. Acidification is required during post-reaction processing; otherwise, the product will not precipitate as a solid, leading to difficulties in separation and purification.

[0063] S3: A mixture of compound 2, SOCl2, and DMF is stirred in anhydrous CH2Cl2 at 20-50°C for 3-24 hours; then a Lewis acid is added, and the mixture is stirred at 20-50°C for 1-48 hours. The precipitate is filtered off and stirred in an aqueous alkaline solution for 5-60 minutes. After filtration, the residue is washed with excess water and organic solvent and dried to obtain compound 3. Preferably, the mixture of compound 2, SOCl2, and DMF is stirred in anhydrous CH2Cl2 at 40°C for 5 hours. Preferably, the Lewis acid is SnCl4, and the mixture is stirred at 40°C for 5 hours, while the base is NaOH, and the mixture is stirred for 30 minutes.

[0064] The specific procedure is as follows: A mixture of compound 2, SOCl2, and DMF is stirred in anhydrous CH2Cl2 at 20 to 50°C for 3 to 24 hours. Then, a Lewis acid (SnCl4, TiCl4, or Et2O.BF3) is added, and the mixture is stirred at 20 to 50°C for 1 to 48 hours. The precipitate is filtered off and stirred in an aqueous solution of alkali (NaOH, KOH, Na2CO3, or NaHCO3) for 5 to 60 minutes. After filtration, the residue is washed with excess water and acetone (or methanol, ethanol, acetonitrile, or ethyl acetate) and dried to obtain solid compound 3.

[0065] The first sub-step of step S3 is the preparation of acyl chloride from acid. It is necessary to monitor the formation of acyl chloride. If the acyl chloride equivalent is insufficient or the reaction time is insufficient, the carboxylic acid will not be completely converted into the intermediate state of acyl chloride. The next step can only be carried out after it is completely converted into acyl chloride. The second sub-step is the Friedel-Crafts acylation reaction catalyzed by Lewis acid. Lewis acid needs to be added slowly. If the addition rate is too fast, the reaction will become more complicated. Although the product cannot be dissolved, the reaction can be monitored by monitoring the presence of the starting material in the solution and the ring closure. If the reaction time is insufficient or the temperature is too low, two ring closure situations will occur. This requires careful observation during monitoring and adjustment of time and temperature to push the reaction to the endpoint.

[0066] S4 dissolves compound 3 in solvent 3; under nitrogen protection, a solution of borane-containing solvent 3 is added dropwise at 0°C; then the reaction mixture is stirred at 30-100°C for 3-48 hours; after the reaction is complete, the reaction solution is cooled to room temperature; water is slowly added dropwise to the solution, then an aqueous solution of base is added, and the mixture is stirred for 5-60 minutes; the solid is obtained by filtration and washed several times with water or other organic solvents; the obtained solid is dried to obtain compound 4. Preferably, solvent 3 is tetrahydrofuran, and the reaction mixture is stirred at 65°C for 16 hours; preferably, the base is sodium hydroxide, and an aqueous solution of sodium hydroxide is added, and the mixture is stirred for 30 minutes.

[0067] The specific procedure is as follows: Compound 3 is dissolved in solvent 3 (THF, DCM, DMF, DMA, DMSO, or 1,4-dioxane). Under nitrogen protection, a solution of borane in solvent 3 (THF, DCM, DMF, DMA, DMSO, or 1,4-dioxane) is added dropwise at 0°C. The reaction mixture is then stirred at 30 to 100°C for 3 to 48 hours. After the reaction is complete, the reaction solution is cooled to room temperature. Water is slowly added dropwise to the solution, followed by an aqueous solution of alkali (NaOH, KOH, Na2CO3, or NaHCO3), and the mixture is stirred for 5 to 60 minutes. The resulting mixture is filtered, and the solid is washed several times with water (or methanol, ethanol, acetone, ethyl acetate, or DCM). The obtained solid is dried in a vacuum drying oven to obtain solid compound 4.

[0068] Step S4 is the reduction of the ketone carbonyl group. The specific reaction principle is as follows:

[0069]

[0070] There are many reducing agents available for the reduction of ketones, such as metal hydride reduction, silane reduction, catalytic hydrogenation, and formic acid reduction. However, the reaction results often vary greatly depending on the substrate, due to differences in symmetry, electronegativity, and steric hindrance. We experimented with NaBH3CN reduction, Et3SiH reduction, catalytic hydrogenation, and formic acid reduction, but none of these conditions were suitable for our substrate. Ultimately, the inventors unexpectedly discovered that borane reduction could directly reduce the ketone carbonyl group to a methylene group, presumably because the alcohol is in the benzylic position and can therefore be reduced.

[0071] In this invention, CuX is a copper halide, DMF is N,N-dimethylformamide, DMSO is dimethyl sulfoxide, NMP is N-methylpyrrolidone, THF is tetrahydrofuran, Et2O·BF3 is boron trifluoride diethyl ether complex, DCM is dichloromethane, DMA is N,N-dimethylacetamide, 1,4-dioxane is 1,4-dioxane or dioxane, and Et3SiH is triethylsilane.

[0072] The above is a detailed description of the present invention. The following are embodiments of the present invention.

[0073] Example 1

[0074] Step S1: Methyl anthranilate SM1 (7.8 g, 51.6 mmol, 1.0 eq.), methyl 2-iodobenzoate SM2 (37.9 g, 144.5 mmol, 2.8 eq.), K2CO3 (18.0 g, 130.1 mmol, 2.5 eq.), Cu (0.7 g, 10.3 mmol, 0.2 eq.), and CuI (1.0 g, 5.2 mmol, 0.1 eq.) were dissolved in diphenyl ether (50 ml) and heated to 190 °C under N2 protection for 72 hours. The solvent was removed under reduced pressure, and the residue was purified by silica gel column chromatography (4:1 hexane / ethyl acetate) to give a yellow solid compound 1 (2,2',2”-trimethyl hypoazinetribenzoate) (5.1 g, yield 24%). Compound 1 was analyzed to obtain... Figure 1 The 1H-NMR spectrum, 1H-NMR (400MHz, CDCl3): δ7.59 (d, J=9.2Hz, 3H), 7.39-7.33 (m, 3H), 7.12-7.02 (m, 6H), 3.37 (s, 9H).

[0075] Step S2: In a 250 mL round-bottom flask, compound 1 (3.0 g, 7.2 mmol, 1.0 eq.) and sodium hydroxide (3.0 g, 75.1 mmol, 10.4 eq.) were dissolved in an aqueous ethanol solution (1:1, 80 mL, v / v) and refluxed for 16 hours. After hydrolysis, the mixture was cooled to room temperature, concentrated to half its original volume, acidified with concentrated hydrochloric acid, and the precipitated solid was filtered under reduced pressure and washed with plenty of water. The residue was dried overnight in a vacuum drying oven at 45 °C to obtain a pale yellow powder, compound 2 (2,2',2”-tribenzoic acid) (2.50 g, 93% yield). Compound 2 was analyzed to obtain... Figure 2 The 1H-NMR spectrum, 1H-NMR (400MHz, DMSO-d6): δ 12.61 (s, 3H), 7.62 (d, J = 7.0Hz, 3H), 7.44 (t, J = 8.3Hz, 3H), 7.20 (t, J = 7.4Hz, 3H), 6.75 (d, J = 7.0Hz, 3H).

[0076] Step S3: A mixture of compound 2 (2.2 g, 5.8 mmol, 1.00 eq.), SOCl2 (20 mL), and DMF (0.50 mL) was stirred at 40 °C for 5 hours in anhydrous CH2Cl2 (60 mL). Then, SnCl4 (0.6 mL, 5.2 mmol, 0.95 eq.) was added, and the solution was stirred at 40 °C for 20 hours. A yellow precipitate was filtered off and stirred in NaOH aqueous solution (1 M, 100 mL) for 30 minutes. After filtration, the residue was washed with excess water and acetone and dried to give a yellow solid compound 3 (4H-benzo[9,1]quinolinyl[3,4,5,6,7-defg]acrid-4,8,12-trione) (1.6 g, yield 84%). Compound 3 was analyzed to obtain… Figure 3 The 1H-NMR spectrum, 1H-NMR (400MHz, CDCl3+TFA): δ 9.22 (d, J = 7.7Hz, 6H), 8.07 (t, J = 7.8Hz, 3H).

[0077] Step S4: Compound 3 (200 mg, 0.6 mmol, 1.0 eq.) was dissolved in tetrahydrofuran (4.0 mL). Under nitrogen protection, a THF solution of borane (1 M, 4 mL, 6.7 eq.) was added dropwise at 0 °C, completing the addition over 10 minutes. The reaction mixture was then stirred at 65 °C for 16 hours. After the reaction was complete, the reaction solution was cooled to room temperature. Water was slowly added dropwise to the solution, followed by 2 M sodium hydroxide, and the mixture was stirred for 30 minutes. The resulting mixture was filtered, and the solid was washed several times with water. The obtained solid was dried in a vacuum drying oven to give a yellow solid, compound 4 (8,12-dihydro-4H-benzo[9,1]quinazazido[3,4,5,6,7-defg]acridine) (130 mg, 84% yield). Compound 4 was analyzed to obtain… Figure 4 The 1H-NMR spectrum of compound 4 was obtained (400 MHz, CDCl3): δ 7.07–6.90 (m, 9H), 4.18 (s, 6H). Compound 4 was then analyzed to obtain... Figure 5 The 13C-NMR spectrum of compound 4 was obtained. 13C-NMR (100 MHz, CDCl3): δ 135.24, 127.08, 122.90, 120.56, 31.49. Further analysis of compound 4 yielded... Figure 6 The HPLC chromatogram, HPLC (254 nm): 96.3%.

[0078] Example 2

[0079] Step four is the key reaction for reducing the carbonyl group of the ketone. Many reducing agents can be used for ketone reduction, such as metal hydride reduction, silane reduction, catalytic hydrogenation, and formic acid reduction, etc. However, the reduction reaction of this substrate 3 has not been reported. We conducted a series of reaction attempts with this substrate. Since compound 3 is only soluble in TFA (common laboratory solvents are insoluble, including DMSO, DMF, THF, DCM, MeOH, EA, HFIP, etc.), we also tested different solvent combinations with and without TFA. The specific conditions and results are shown in the table below (all were monitored by NMR after processing).

[0080]

[0081]

[0082] The reduction conditions for benzophenone were investigated, and the following conditions can reduce the ketone carbonyl group to a methylene group: NaBH3CN reduction, Et3SiH reduction, catalytic hydrogenation, and formic acid reduction. The reaction principle is as follows:

[0083]

[0084] However, the reaction results often vary greatly for each different substrate due to differences in symmetry, electronegativity, and steric hindrance. In our actual use of the reagents described above, these conditions were not applicable to the substrates of this invention. Surprisingly, however, the borane reduction conditions could directly reduce the ketone carbonyl group to a methylene group, likely because the alcohol is in the benzylic position, making it easier to reduce.

[0085] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be considered as limitations on the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a benzoquinolizinoacridine compound, characterized by, The synthetic route is as follows: The preparation steps are as follows: S1, methyl anthranilate, methyl 2-halobenzoate, a base, Cu and CuX are dissolved in solvent 1, heated to 120-250 DEG C, reaction for 6-144 hours; remove the solvent under reduced pressure, the residue is purified to obtain compound 1; S2, compound 1 and a base are dissolved in solvent 2, refluxed for 2-48 hours; after hydrolysis is completed, cooled to room temperature, concentrated, acidified with concentrated hydrochloric acid, the precipitated solid is filtered under reduced pressure and washed with water; the filter residue is dried overnight to obtain compound 2; S3, a mixture of compound 2, SOCl2 and DMF is stirred in anhydrous CH2Cl2 at 20-50 DEG C for 3-24 hours; then a Lewis acid is added, stirred at 20-50 DEG C for 1-48 hours, the precipitate is filtered, stirred in an aqueous base for 5-60 minutes; after filtration, the residue is washed with water and an excess of an organic solvent and dried to obtain compound 3; S4, compound 3 is dissolved in solvent 3; under nitrogen protection, a solution containing borane is added dropwise at 0 DEG C; then the reaction mixture is stirred at 30-100 DEG C for 3-48 hours; after the reaction is completed, the reaction solution is cooled to room temperature; water is slowly added dropwise to the solution, then an aqueous base is added, and the mixture is stirred for 5-60 minutes; filtration gives a solid, which is washed with water or other organic solvents several times; the obtained solid is dried to obtain compound 4.

2. The method for preparing benzoquinazidine compounds according to claim 1, characterized in that, In step S1, the base is one or more of K3PO4, Na2CO3, K2CO3 or Cs2CO3.

3. The method for preparing benzoquinazidine compounds according to claim 1, characterized in that, In step S1, the CuX is a copper halide.

4. The method for preparing benzoquinazidine compounds according to claim 1, characterized in that, In step S1, the solvent 1 is one or more of DMSO, DMF, NMP, THF, toluene or diphenyl ether.

5. The method for preparing benzoquinazine-acridine compounds according to claim 1, characterized in that, In step S2, the base is one or more of LiOH, NaOH or KOH.

6. The method for preparing benzoquinazine-acridine compounds according to claim 1, characterized in that, In step S2, the solvent 2 is one or more of methanol, ethanol, acetonitrile or tetrahydrofuran.

7. The method for preparing benzoquinazine-acridine compounds according to claim 1, characterized in that, In step S2, the volume ratio of compound 1 and the base to solvent 2 is 1-10:1-10.

8. The method for preparing benzoquinazidine compounds according to claim 1, characterized in that, In step S3, the Lewis acid is one or more of SnCl4, TiCl4 or Et2O.BF3.

9. A benzoquinazine-acridine compound, characterized in that, Prepared by the method of any one of claims 1-8.

10. Use of a benzochinazinoacridine compound according to claim 9, characterized in that, The benzochinazinoacridine compound is used as a mother nucleus in the preparation of optoelectronic functional materials.

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