A fused fluorenone compound and a preparation method and application thereof
Patent Information
- Application Number
- CN202611480824.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-22
- Publication Date
- 2026-10-27
AI Technical Summary
[0030]上述稠合芴酮类化合物作为发光材料或光学功能分子骨架的应用。
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Abstract
Description
Technical Field
[0001] This invention belongs to the fields of organic synthetic chemistry, polycyclic aromatic compounds and organic optoelectronic functional materials, specifically relating to a fused fluorenone compound and its preparation method and application. Background Technology
[0002] Fluorenones and their derivatives are an important class of polycyclic aromatic ketones, whose molecular structures simultaneously contain a rigid aromatic skeleton and an electron-attracting carbonyl group. By further extending the π-conjugation of the fluorenone skeleton, fused aromatic compounds with different electronic structures and optical properties can be obtained.
[0003] Highly fused fluorenones possess a large π-conjugated skeleton and high molecular rigidity. Furthermore, their carbonyl groups can influence the electron distribution and frontier molecular orbital energy levels, thus serving as structural units for constructing organic conjugated functional molecules. In addition, the carbonyl group of fluorenones can undergo further reduction, condensation, olefination, and other functional group transformations, providing these compounds with significant structural potential for the synthesis of complex polycyclic aromatic molecules.
[0004] However, for already constructed fused polycyclic aromatic systems, further introducing a five-membered ring ketone structure at a specific position usually requires solving problems such as controlling the reaction site and forming new carbon-carbon bonds. Therefore, developing a method that can directly utilize existing functional groups in fused aromatic hydrocarbons to achieve intramolecular ring closure, thereby rapidly constructing a highly fused fluorenone skeleton, is of great significance.
[0005] This invention discovers that a class of ester-containing fused aromatic compounds with specific spatial relationships can undergo intramolecular ring closure under the action of ferric chloride, transforming the original ester group into a fluorenone carbonyl group, while simultaneously forming a new carbon-carbon bond between the carbonyl carbon and the adjacent aromatic ring, thereby obtaining a new fused fluorenone compound in one step.
[0006] Further UV-Vis absorption spectroscopy, fluorescence spectroscopy, and frontier molecular orbital studies showed that the obtained fused fluorenone compounds have distinct light absorption and emission characteristics, and possess HOMO / LUMO energy levels suitable for further molecular electronic structure regulation, providing a basis for their use as building blocks for organic optical and optoelectronic functional molecules. Summary of the Invention
[0007] The purpose of this invention is to provide a fused fluorenone compound, its preparation method, and its application. This invention mainly addresses the following technical problems:
[0008] First, a method is provided for directly constructing a highly fused fluorenone skeleton from ester-containing fused aromatic hydrocarbons.
[0009] By utilizing the existing carboxylic acid ester groups in the raw material molecule as the carbonyl source, the construction of new carbon-carbon bonds and five-membered ring ketone structures is completed simultaneously through intramolecular ring closure, reducing the additional steps required for the further conversion of carboxylic acid esters into carboxylic acids, acyl halides, or other activated acyl compounds.
[0010] Second, it provides a new class of polycyclic fused fluorenone compounds.
[0011] By further constructing a five-membered ring of fluorenone on the original polycyclic aromatic hydrocarbon skeleton, novel aromatic ketone compounds with higher degree of fusion and rigid π-conjugated structure were obtained.
[0012] Third, the novel fused fluorenone compound is endowed with further optical and optoelectronic functional applications.
[0013] By utilizing the conjugation between the fused aromatic skeleton, carbonyl group, and peripheral aryl group, the absorption, emission, and HOMO / LUMO energy levels of the molecule can be regulated, providing a new molecular skeleton for the further construction of organic functional molecules with specific optical and electronic properties.
[0014] To achieve the above objectives, the present invention adopts the following technical solution:
[0015] A fused fluorenone compound has the following structure:
[0016] R is H or COOEt.
[0017] The synthetic route for preparing the above-mentioned fused fluorenone compounds is as follows:
[0018]
[0019] The preparation process is as follows:
[0020] (1) Compound 1 and compound 2 are reacted in an alcohol solvent in the presence of a base to obtain cyclopentadienone compound 3;
[0021] Furthermore, the molar ratio of compound 1 to compound 2 is 1:(1~1.5), the base is potassium hydroxide, the alcohol solvent is ethanol, and the reaction is carried out at room temperature.
[0022] (2) Under a protective atmosphere, compound 3 is reacted with acetylacetic acid ester in a high-boiling organic solvent to obtain fused aromatic compound 4 containing carboxylic acid ester group;
[0023] Further, the molar ratio of compound 3 to the acetylacetic acid ester is 1:(2~3), the high-boiling-point organic solvent is diphenyl ether, and the reaction temperature is 200~240°C. In a preferred embodiment, the reaction temperature is about 220°C.
[0024] Through the above reaction, a new aromatic ring is further formed on the original polycyclic aromatic skeleton, and an ethyl carboxylic acid ester group is introduced to obtain the ester-containing fused aromatic hydrocarbon precursor required for subsequent intramolecular ring closure.
[0025] The carboxylic acid ester group in compound 4 has a spatial positional relationship with the adjacent aromatic ring that is suitable for further formation of a five-membered ring.
[0026] (3) Under a protective atmosphere, compound 4 is dissolved or dispersed in an organic solvent, and ferric chloride is added to react, causing compound 4 to undergo intramolecular cyclization, to obtain fused fluorenone compound 5.
[0027] Furthermore, the molar ratio of compound 4 to ferric chloride is 1:(20~30). The organic solvent is dichloromethane.
[0028] In this reaction, the carboxylic acid ester group in compound 4 participates in intramolecular ring closure, the alkoxy group in the ester group leaves, the ester carbonyl group is converted into the ketone carbonyl group in the resulting five-membered ring, and at the same time, a new carbon-carbon bond is formed between the carbonyl carbon and the spatially adjacent aromatic ring, thereby further forming a fluorenone structure on the original fused aromatic ring skeleton.
[0029] It should be noted that ferric chloride is currently believed to activate the carboxylic acid ester group in compound 4 and promote subsequent intramolecular cyclization, but this process may include ester group activation, intramolecular carbon-carbon bond formation, and other consecutive steps.
[0030] The above-mentioned fused fluorenone compounds are used as luminescent materials or optical functional molecular frameworks.
[0031] This invention is not limited to the specific reaction mechanism described above.
[0032] Any technical solution that uses ferric chloride to induce intramolecular cyclization of ester-containing fused aromatic hydrocarbons with corresponding structural characteristics and form corresponding fused fluorenone structures can be included in the technical concept of this invention.
[0033] Compared with the prior art, the present invention has the following beneficial effects.
[0034] (1) A method for directly constructing a five-membered ring of fluorenone from a carboxylic acid ester is provided.
[0035] This invention uses an ester-containing fused aromatic compound 4 as a direct precursor to achieve intramolecular cyclization under the action of ferric chloride. The original carboxylic acid ester group serves as both a cyclizing functional group and a source of the final fluorenone carbonyl group, forming new carbon-carbon bonds during the reaction, thereby completing the construction of a new five-membered ring ketone structure in one step.
[0036] (2) Avoid multi-step pre-activation of ester groups
[0037] This invention eliminates the need to first hydrolyze the carboxylic ester into carboxylic acid and then convert it into acyl chloride or other activated acyl intermediates, allowing for direct intramolecular cyclization, which simplifies the synthetic route.
[0038] (3) It can rapidly improve the degree of molecular cohesion.
[0039] By converting compound 4 into compound 5, a five-membered ring can be further constructed on the existing polycyclic aromatic skeleton, achieving further fusion of the molecular skeleton and forming a polycyclic aromatic ketone structure with higher rigidity and a further extended π-conjugation range.
[0040] (4) The product obtained is a novel fused fluorenone skeleton with potential for further functional development.
[0041] Compound 5 possesses: a highly fused aromatic π-skeleton; a rigid polycyclic structure; a fluorenone carbonyl group; and a peripheral aromatic structure that can be further modified. Therefore, it can serve not only as a synthetic intermediate for complex polycyclic aromatic compounds but also as a molecular framework for organic optical and optoelectronic functional molecules. Attached Figure Description
[0042] Figure 1 It is compound 4a (ethyl 1,4-diphenyltriphenyl-2-carboxylate). 1 H NMR spectrum;
[0043] Figure 2 It is compound 5a (5-phenyl-7H-indenzo[1,2-a]triphenyl-7-one) 1 H NMR spectrum;
[0044] Figure 3 The HRMS spectrum of compound 5a (5-phenyl-7H-indenzo[1,2-a]triphenyl-7-one);
[0045] Figure 4 It is compound 4b (diethyl 1,4-diphenyltriphenyl-2,3-dicarboxylic acid). 1 H NMR spectrum;
[0046] Figure 5 It is compound 5b (ethyl 7-oxo-5-phenyl-7H-indeno[1,2-a]triphenyl-6-carboxylate). 1 HNMR spectrum;
[0047] Figure 6 This is the HRMS spectrum of compound 5b (ethyl 7-oxo-5-phenyl-7H-indenzo[1,2-a]triphenyl-6-carboxylate);
[0048] Figure 7Compound 5a (5-phenyl-7H-indenzo[1,2-a]triphenyl-7-one) in dichloromethane solution (1×10⁻⁶) -5 The UV-Vis absorption spectrum in (mol / L);
[0049] Figure 8 Compound 5a (5-phenyl-7H-indenzo[1,2-a]triphenyl-7-one) in dichloromethane solution (1×10⁻⁶) -5 Fluorescence excitation-emission spectrum in (mol / L);
[0050] Figure 9 These are solid-state luminescence photographs of compound 5a (5-phenyl-7H-indenzo[1,2-a]triphenyl-7-one) under fluorescent and 365nm ultraviolet light irradiation, as well as a concentration of 1×10⁻⁶. -3 A photograph of the luminescence of a mol / L dichloromethane solution excited at 365 nm;
[0051] Figure 10 Compound 5b (ethyl 7-oxo-5-phenyl-7H-indeno[1,2-a]triphenyl-6-carboxylate) in dichloromethane solution (1×10⁻⁶) -5 The UV-Vis absorption spectrum in (mol / L);
[0052] Figure 11 Compound 5b (ethyl 7-oxo-5-phenyl-7H-indeno[1,2-a]triphenyl-6-carboxylate) in dichloromethane solution (1×10⁻⁶) -5 Fluorescence excitation-emission spectrum in (mol / L);
[0053] Figure 12 These are solid-state luminescence photographs of compound 5b (7-oxo-5-phenyl-7H-indeno[1,2-a]triphenyl-6-carboxylic acid ethyl ester) under fluorescent and 365nm ultraviolet light irradiation, and a concentration of 1×10 -3 A photograph of the luminescence of a mol / L dichloromethane solution excited at 365 nm;
[0054] Figure 13 The HOMO and LUMO levels of compounds 5a (5-phenyl-7H-indeno[1,2-a]triphenyl-7-one) and 5b (ethyl 7-oxo-5-phenyl-7H-indeno[1,2-a]triphenyl-6-carboxylate) were calculated using Gaussian 16 software at the B3LYP / 6-31G(d,p) level. Detailed Implementation
[0055] Example 1
[0056] The synthetic route for compound 5a (5-phenyl-7H-indenzo[1,2-a]triphenyl-7-one) is as follows:
[0057]
[0058] Synthesized compound 3 (1,3-diphenyl-2H-cyclopentano[l]phenanthrene-2-one):
[0059] In a 150 mL single-necked flask, add 1.60 g (7.68 mmol) of 9,10-phenanthroquinone, 1.62 g (7.70 mmol) of dibenzyl ketone, and 60 mL of anhydrous ethanol. Add 0.44 g (7.84 mmol) of KOH to 20 mL of anhydrous ethanol and shake for 5 min until the KOH is completely dissolved. Add the ethanol solution of KOH to the single-necked flask and stir at room temperature for 20 min. Filter and wash three times with 5 mL of anhydrous ethanol. Dry to obtain 2.59 g of black powder, which is used directly in the next reaction without purification.
[0060] Synthesize compound 4a (ethyl 1,4-diphenyltriphenyl-2-carboxylate):
[0061] Take a 100 mL single-necked flask and add compound 3 (1.0 g, 2.61 mmol), ethyl propynate (0.9 g, 5.2 mmol), and 4 mL of diphenyl ether sequentially. Under a nitrogen atmosphere, heat to 220 °C in a sand bath and react until the black color disappears (about 3 min) and a light brownish-yellow transparent liquid appears. Cool to room temperature. Pour the reaction solution into 10 mL of anhydrous ethanol and stir for 2 min. Then, place the mixture in an ice-water bath and cool for 5 min. Filter. Wash the residue three times with 5 mL of anhydrous ethanol, then three times with 5 mL of petroleum ether. Dry to obtain a light grayish-green powder. Dissolve the powder in dichloromethane, add an appropriate amount of silica gel, and evaporate to dryness until powdery. Dry loading and purification by silica gel column chromatography with eluent CH2Cl2:PE (petroleum ether) = 1:5 (volume ratio) yields 0.78 g of white solid (compound 4a), with a yield of 55.2%. 1 H NMR spectrum as follows Figure 1 As shown, 1H NMR (400 MHz, Chloroform-d) δ ppm: 8.41 (d, J = 8.2 Hz, 2H), 7.56 (d, J = 8.6, 2H), 7.44 (d, J = 8.2, 2H), 7.39 (s, 10H), 7.04 (d, J = 8.4, 2H), 4.01 (q, J = 7.1,4H), 0.94 (t, J = 7.1, 6H). HRMS (TOF MS ES+): m / z calculated C 34 H 24 NaO4 [M+Na] + 519.1572, found 519.1574.
[0062] Synthesize compound 5a (5-phenyl-7H-inden[1,2-a]triphenyl-7-one):
[0063] In a 50 mL single-necked flask, compound 4a (0.91 g, 2.0 mmol), anhydrous FeCl3 (0.97 g, 6.0 mmol), and anhydrous dichloromethane were added. 20 mL of the mixture was added, and the reaction was stirred at room temperature for 4 h under nitrogen protection. The reaction was quenched with 2 mL of anhydrous methanol. Extraction was performed with dichloromethane (3 × 10 mL), and the mixture was dried over anhydrous sodium sulfate. Silica gel column chromatography was performed with CH₂Cl₂:PE = 1:5 (volume ratio) as eluent to give 0.61 g of an orange solid (compound 5a), with a yield of 75.03%. Compound 5a... 1 H NMR spectrum as follows Figure 2 As shown, 1 ¹H NMR (400 MHz, Chloroformed) δ ppm: 8.74 (d, J = 9.4 Hz, 1H), 8.46 (d, J = 8.1 Hz, 1H), 8.41 (d, J = 9.5 Hz, 1H), 7.97 (d, J = 7.6 Hz, 1H), 7.79 (s, 1H), 7.74-7.61 (m, 3H), 7.55-7.33 (m, 8H), 7.28 (d, J = 6.5 Hz, 1H), 7.07 (d, J = 8.4, 1H). The HRMS spectrum of compound 5a is shown below. Figure 3 As shown, HRMS (TOF MS ES+): m / z calculatedC 31 H 19 O [M+H] +407.1436, found 407.1437.
[0064] Example 2:
[0065]
[0066] Synthesize compound 4b (diethyl 1,4-diphenyltriphenyl-2,3-dicarboxylic acid):
[0067] Take a 100 mL single-necked flask and add the above-mentioned black powder (1.0 g, 2.61 mmol), diethyl butyrynethide (0.9 g, 5.2 mmol), and 4 mL of diphenyl ether sequentially. Under a nitrogen atmosphere, heat to 220 °C in a sand bath and react until the black color disappears (about 3 min) and a light brownish-yellow transparent liquid appears. Cool to room temperature. Pour the reaction solution into 10 mL of anhydrous ethanol and stir for 2 min. In an ice-water bath for 5 min, filter. Wash the residue three times with 5 mL of anhydrous ethanol, then three times with 5 mL of petroleum ether. Dry to obtain a light grayish-green powder. Dissolve the powder in dichloromethane, add an appropriate amount of silica gel, and evaporate to dryness until powdery. Dry sample loading and purification by silica gel column chromatography with eluent CH2Cl2:PE = 1:5 (volume ratio) to obtain 0.78 g of white solid (compound 4b), yield 55.2%. 1 H NMR spectrum as follows Figure 4 As shown, 1 H NMR (400 MHz, Chloroform-d) δ ppm:8.41 (d, J = 8.2 Hz, 2H), 7.56 (d, J = 8.6, 2H), 7.44 (d, J = 8.2, 2H), 7.39(s, 10H), 7.04 (d, J = 8.4, 2H), 4.01 (q, J = 7.1, 4H), 0.94 (t, J = 7.1,6H). HRMS (TOF MS ES+): m / z calculated C 36 H 28 NaO4 [M+Na] + 547.1885, found547.1887.
[0068] Synthesize compound 5b (ethyl 7-oxo-5-phenyl-7H-indeno[1,2-a]triphenyl-6-carboxylate):
[0069] In a 50 mL single-necked flask, compound 4b (0.16 g, 0.31 mmol), anhydrous FeCl3 (0.15 g, 0.93 mmol), and anhydrous dichloromethane were added. 20 mL of the solution was added, and the mixture was stirred at room temperature for 4 h under nitrogen protection. The reaction was quenched with anhydrous methanol. Extraction was performed with dichloromethane and dried over anhydrous sodium sulfate. Silica gel column chromatography was performed with CH2Cl2:PE as eluent (1:5, v / v) to give 0.102 g of an orange solid (compound 5b), yielding 68.7%. 1 H NMR spectrum as follows Figure 5 As shown, 1 ¹H NMR (400 MHz, Chloroform-d) δ ppm: 8.77 (d, J = 6.9 Hz, 1H), 8.47 (d, J = 9.4 Hz, 2H), 7.97 (d, J = 7.6 Hz, 1H), 7.73 (t, J = 7.0 Hz, 2H), 7.63 -7.30 (m, 10H), 7.08 (t, J = 7.1 Hz, 1H), 4.29 (q, J = 7.2 Hz, 2H), 1.20 (t, J = 7.1 Hz, 3H). The HRMS spectrum of compound 5b is shown below. Figure 6 Shown, HRMS (TOF MS ES+): m / z calculated C 34 H 23 O3 [M+H] + 479.1647, found 479.1650.
[0070] Application Example 1: Optical properties of compounds 5a and 5b
[0071] (1) Ultraviolet-visible absorption spectrum
[0072] Compound 5a was dissolved in dichloromethane to prepare a solution of 1×10⁻⁶. -5 A dilute solution of mol / L was tested, and its UV-Vis absorption spectrum was measured. The results are as follows: Figure 7 As shown in the figure, experimental results indicate that compound 5 exhibits significant characteristic absorption in the ultraviolet and visible light regions. The maximum absorption wavelength is 247 nm, the long-wavelength absorption peak is 333 nm, and the absorption edge is 500 nm. These results demonstrate that the highly fused π-conjugated framework of compound 5 can generate significant electronic transitions and optical absorption behavior.
[0073] Compound 5b was dissolved in dichloromethane to prepare a solution of 1×10⁻⁶. -5 A dilute solution of mol / L was tested, and its UV-Vis absorption spectrum was measured. The results are as follows: Figure 10As shown in the figure, experimental results indicate that compound 5b exhibits significant characteristic absorption in the ultraviolet and visible light regions. The maximum absorption wavelength is 240 nm, the long-wavelength absorption peak is 332 nm, and the absorption edge is 500 nm. These results demonstrate that the highly fused π-conjugated framework of compound 5b can generate significant electronic transitions and optical absorption behavior.
[0074] (2) Fluorescence spectroscopy test
[0075] Compound 5a was dissolved in dichloromethane to prepare a solution of 1×10⁻⁶. -5 A dilute solution of mol / L was used to test its fluorescence spectrum, and the results are as follows: Figure 8 As shown. By Figure 8 It was found that compound 5 exhibited characteristic fluorescence emission when excited by 333 nm light. Specifically, the excitation wavelength was 333 nm, the maximum emission wavelength was 560 nm, the Stokes shift was 227 nm, and the maximum emission intensity was 143863 a.u. These results indicate that compound 5a can produce a significant fluorescence response under photoexcitation conditions, suggesting its potential for further development as a luminescent material or optical functional molecular framework.
[0076] Compound 5b was dissolved in dichloromethane to prepare a solution of 1×10⁻⁶. -5 A dilute solution of mol / L was used to test its fluorescence spectrum, and the results are as follows: Figure 11 As shown. By Figure 11 It was found that compound 5b exhibited characteristic fluorescence emission when excited by 333 nm light. Specifically, the excitation wavelength was 333 nm, the maximum emission wavelength was 544 nm, the Stokes shift was 211 nm, and the maximum emission intensity was 167292 a.u. These results indicate that compound 5b can produce a significant fluorescence response under photoexcitation conditions, suggesting its potential for further development as a luminescent material or optical functional molecular framework.
[0077] (3) Solid-state luminescent photographs
[0078] Solid-state luminescence images of compound 5a under fluorescent lamp and 365nm UV lamp illumination, and solution luminescence images under 365nm UV lamp illumination are shown below. Figure 9 As shown. The solution is compound 5a dissolved in dichloromethane, prepared to a concentration of 1×10⁻⁶. -3 The luminescence image of a dilute solution of mol / L under 365nm excitation is shown below. Figure 9 As shown, by Figure 9 It is known that compound 5a exhibits bright orange-yellow fluorescence in both the solid and solution states.
[0079] Solid-state luminescence images of compound 5b under fluorescent lamp and 365 nm UV lamp illumination, and solution luminescence images under 365 nm UV lamp illumination are shown below. Figure 12 As shown. The solution is compound 5b dissolved in dichloromethane, prepared to a concentration of 1×10⁻⁶. -3 The luminescence image of a dilute solution of mol / L under 365nm excitation is shown below. Figure 12 As shown, by Figure 12 It is known that compound 5b exhibits bright yellow fluorescence in both the solid and solution states.
[0080] (4) Density functional theory calculations and discussion of results
[0081] To further elucidate the intrinsic relationship between the electronic structure and photophysical properties of the target compounds, Gaussian 16 software was used to calculate the frontier molecular orbital distributions and energy levels of compounds 5a and 5b at the B3LYP / 6-31G(d,p) level based on DFT. Figure 13 As shown, compound 5a has a HOMO level of -5.88 eV, a LUMO level of -1.54 eV, and a HOMO-LUMO band gap of 4.34 eV. Compound 5b has a HOMO level of -5.89 eV, a LUMO level of -1.58 eV, and a HOMO-LUMO band gap of 4.32 eV. The decrease in band gap indicates a redshift in the molecular absorption and emission spectra, consistent with experimental results from UV-Vis absorption spectroscopy.
[0082] The fused fluorenone compounds prepared by this invention possess a rigid polycyclic aromatic skeleton and a carbonyl group, and can be mainly used in the following aspects:
[0083] First, it serves as a synthetic intermediate for polycyclic aromatic compounds. The carbonyl group of fluorene can undergo further reactions such as reduction, olefination, condensation, and nucleophilic addition, thus transforming it into different types of fluorene, fluoreneene, spirocyclic, and other fused aromatic compounds.
[0084] Second, it serves as a building block for organic conjugated functional molecules. By altering the peripheral substituents of fused aromatic hydrocarbons or further extending the π-conjugated structure, the absorption, luminescence, and electronic structure of the molecule can be modulated.
[0085] Third, as precursors or structural units of organic optoelectronic materials. Fused aromatic skeletons can provide a large π-conjugated system, while fluorenone carbonyl groups have certain electron acceptor characteristics, which can be used to further design organic semiconductors and optoelectronic functional molecules with donor-acceptor structures.
[0086] Fourth, it serves as a precursor for the synthesis of fluorescent, absorption, and sensing functional molecules. Different electron-donating or electron-withdrawing groups can be further introduced into the carbonyl group and the surrounding aromatic ring of fluorenone to construct functional molecules with different spectral properties.
[0087] Fifth, it serves as a synthetic intermediate for fine chemicals and novel polycyclic aromatic ketone compounds.
[0088] In the absence of further experimental data on device performance, photophysical properties, or bioactivity, the present invention preferably describes the above uses as "synthetic intermediates," "functional molecular building blocks," or "organic optoelectronic material precursors," without limiting specific device performance or biomedical applications.
[0089] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A fused fluorenone compound, characterized in that, The structure is as follows: R is H or COOEt.
2. The method for preparing the fused fluorenone compound according to claim 1, characterized in that, The process is as follows: ， (1) Compound 1 and compound 2 are reacted in an alcohol solvent in the presence of a base to obtain cyclopentadienone compound 3; (2) Under a protective atmosphere, compound 3 is reacted with acetylacetic acid ester in a high-boiling organic solvent to obtain fused aromatic compound 4 containing carboxylic acid ester group; (3) Under a protective atmosphere, compound 4 is dissolved or dispersed in an organic solvent, and ferric chloride is added to react, causing compound 4 to undergo intramolecular cyclization, to obtain fused fluorenone compound 5.
3. The method for preparing the fused fluorenone compound according to claim 2, characterized in that, In step (1), the molar ratio of compound 1 to compound 2 is 1:(1~1.5), the base is potassium hydroxide, and the alcohol solvent is ethanol.
4. The method for preparing the fused fluorenone compound according to claim 2, characterized in that, In step (2), the molar ratio of compound 3 to ethyl propynate is 1:(2~3); the high-boiling-point organic solvent is diphenyl ether; and the reaction temperature is 200~240℃.
5. The method for preparing the fused fluorenone compound according to claim 2, characterized in that, In step (3), the molar ratio of compound 4 to ferric chloride is 1:(20~30); the organic solvent is dichloromethane.
6. The application of the fused fluorenone compound of claim 1 as a luminescent material or optical functional molecular framework.