Preparation method and application of spirofluorene-based Grignarene blue-light-emitting material

Abstract

The invention discloses a preparation method and application of a spirofluorenylgrignarene blue-light-emitting material, a spirofluorenylgrignarene fluorescent material molecule G [2] SBF-TFBZ is synthesized by adopting a C-H bond activation gridding method, and the optimal reaction conditions are as follows: palladium acetate Pd (OAc) is used as a catalyst, tri-tert-butylphosphine tetrafluoroborate PtBu2Me-HBF4 is used as a ligand, potassium carbonate is used as alkali, N, N-dimethylacetamide DMAc is used as an organic solvent, and the reaction temperature is 30-60 DEG C, so that the spirofluorenylgrignarene blue-light-emitting material is obtained. Reacting at 120 DEG C for 48 hours, wherein the reaction concentration is 10mmol. L <-1 >; oLED preparation is carried out in the future by adopting a vacuum evaporation technology. According to the specific device structure, ITO serves as an anode, HAT-CN serves as a hole transport layer, TAPC / TcTa / mCP serves as an injection layer, G [2] SBF-TFBZ and [3] TFBZ-[2] SBF serve as light emitting layers respectively, and the test results are as follows: the maximum emission wavelengths of G [2] SBF-TFBZ and [3] TFBZ-[2] SBF are 417 nm and 444 nm respectively, the maximum external quantum efficiency EQEmax is 1.85% and 0.41% respectively, the turn-on voltage of G [2] SBF-TFBZ is 3.9 V, the maximum brightness is 380.7 cd.m <-2 >, and the corresponding current density is 197.1 mA. Cm <- And the turn-on voltage of the [3] TFBZ-[2] SBF is 4.3 V, and the corresponding current density is 187.3 mA. Cm <-2 >. Compared with [3] TFBZ-[2] SBF, the G [2] SBF-TFBZ has stronger brightness and more excellent efficiency and performance.

Description

Technical Field

[0001] The invention belongs to the field of organic electroluminescent devices, and in particular relates to a preparation method and application of a spirofluorene-based aromatic hydrocarbon blue light material. Background Art

[0002] Spirobifluorene is a twisted spiro ring structure formed by two fluorene molecules sharing a carbon atom. It has a unique non-planar spiro conjugation effect, a cross-conformation, and a steric hindrance effect. These characteristics make it show excellent application potential in the field of organic optoelectronic devices. For example, in OLED devices, electrons need to be injected from the cathode into the light-emitting layer, and spirobifluorene has a strong electron affinity, which makes it an efficient electron transport material; in addition, the spiro ring structure of spirobifluorene helps to improve the injection efficiency of charges and reduce the loss of charges during the transmission process, which makes it an excellent hole transport material; most importantly, the conjugated structure of spirobifluorene gives it excellent fluorescence properties. By regulating the structure of spirobifluorene materials, different wavelengths and colors of light can be achieved, which makes it an ideal luminescent material and provides the possibility for the manufacture of efficient and colorful OLEDs. In 2018, we successfully used Yamamoto coupling to successfully prepare spirobifluorene-based "well" lattice. Different from pure spirobifluorene-based lattice aromatics. In this paper, we synthesized a series of [spirobifluorene-fluorophenyl]-based lattice arenes using the CH activation strategy, characterized their optoelectronic properties, and explored their applications in OLEDs. Summary of the invention

[0003] The present invention is achieved by the following technical means, and its reaction process is as follows:

[0004]

[0005] The present invention first discloses a spirofluorene-based aromatic fluorescent material. The specific molecular formula of the fluorescent material is shown in formula (I), and the general molecular formula is shown in formula (II):

[0006] in:

[0007] It is a type of spirofluorene compound;

[0008] Select any one of the following structures:

[0009]

[0010] Select any one of the following structures:

[0011]

[0012] X is selected from any one of F, Cl, Br, I, CH3, NO2, and CH3O.

[0013] Furthermore, the spirofluorene compound The specific structure is as follows:

[0014]

[0015] The present invention also discloses a method for preparing a spirofluorene-based aromatic fluorescent material, comprising:

[0016] Under nitrogen protection, at a reaction temperature of 80-150°C, add a base, a ligand, an organic solvent and a palladium catalyst and react for 36-72 hours.

[0017] The reaction concentration of the reaction system is 10-30mmol·L -1 The molar ratio of type I synthon [2]TFBZ-SBF and dibromospirobifluorene DBrDSBF is 1:1, and the final spirofluorene-based aromatic fluorescent material is obtained.

[0018] Further, the base is selected from: potassium hydroxide, sodium carbonate, sodium bicarbonate, or a combination of two thereof;

[0019] The ligand is selected from: PtBu2Me-HBF4, phosphoramidite ligands, 1,1'-binaphthyl-2,2'-bis(diphenylphosphine) (BINAP), JosiPhos, or a combination of two thereof;

[0020] The organic solvent is selected from: one or a combination of N,N-dimethylacetamide, dimethyl sulfoxide, toluene, and acetonitrile;

[0021] The palladium catalyst is selected from the group consisting of: tetrakis(triphenylphosphine)palladium, palladium acetate, palladium pivalate, palladium trifluoroacetate, diphenylphosphinocenepalladium dichloride, dichlorobistriphenylphosphine palladium, or palladium-carbon or a combination thereof.

[0022] Furthermore, the base is potassium carbonate; the ligand is PtBu2Me-HBF4, the organic solvent is N,N-dimethylacetamide, and the palladium catalyst is palladium acetate.

[0023] Furthermore, the amount of the palladium catalyst substance is 0.025 to 0.05 times that of the synthon.

[0024] Furthermore, the reaction temperature is 120°C, the reaction time is 48h, and the reaction concentration is 10mmol·L -1 .

[0025] The invention also discloses a spirofluorene-based aromatic fluorescent material prepared according to any of the above preparation methods.

[0026] The present invention also discloses an application of any of the above-mentioned spirofluorene-based aromatic hydrocarbon blue light materials in the preparation of an electroluminescent device.

[0027] Furthermore, the electroluminescent device is an organic light emitting diode.

[0028] The beneficial effects of the present invention are:

[0029] 1. The present invention mainly studies the synthesis, properties and applications of [spirobifluorene-fluorophenyl]-based lattice aromatics. First, the step-by-step method is confirmed to be a feasible route through retrosynthetic analysis. At the same time, the optimal reaction conditions are screened out, using Pd(OAc)2 as a catalyst, PtBu2Me-HBF4 as a ligand, K2CO3 as a base, and DMAc as a solvent. When the concentration is 10mmol·L -1 When the concentration is 20mmol·L -1 When the yield of a spirofluorene-based aromatic fluorescent material G[3]SBF-TFBZ is as high as about 5%, the yield is as high as about 5%.

[0030] 2. To explore the influence of lattice size and lattice hole effect on material performance, detailed characterization of their optoelectronic properties (such as Figure 2 As shown). Spectral tests show that in solution, as the lattice size increases, the maximum absorption wavelength of G[3]SBF-TFBZ is red-shifted by 7nm compared with G[2]SBF-TFBZ; while in film, the maximum emission wavelength of G[3]SBF-TFBZ is blue-shifted by 13nm compared with G[2]SBF-TFBZ. It should be noted that in both film and solution states, the maximum emission wavelengths of G[2]SBF-TFBZ and G[3]SBF-TFBZ are blue-shifted compared with linear molecules. In addition, as the lattice size increases, the PLQY of G[3]SBF-TFBZ is lower than that of G[2]SBF-TFBZ. Compared with linear molecules, the fluorescence lifetime of the lattice is shorter, and their PLQYs are close. The electrochemical results show that the band gaps of G[2]SBF-TFBZ, [3]TFBZ-[2]SBF, G[3]SBF-TFBZ and [4]TFBZ-[3]SBF are 3.49 eV, 4.62 eV, 4.07 eV and 3.50 eV, respectively. It can be seen that the band gap of G[2]SBF-TFBZ becomes slightly narrower after lattice formation, but the band gap of G[3]SBF-TFBZ becomes significantly widened.

[0031] 3. They were used as OLED light-emitting layers for application research. The results showed that the turn-on voltage of G[2]SBF-TFBZ was 4V and the maximum brightness reached 380.7cd·m -2, the maximum external quantum efficiency EQEmax1.85%. It can be seen that [spirobifluorene-fluorophenyl]-based lattice aromatic hydrocarbon G[2]SBF-TFBZ has stronger brightness, better efficiency and performance than linear molecules. Surprisingly, the device EL spectrum shows that G[2]SBF-TFBZ effectively suppresses the appearance of the "green band phenomenon". These findings reveal the relationship between molecular structure and luminescence properties, and provide important clues for the directional design of materials with specific luminescence properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The diagrams of the structures of the present invention are as follows: (a) is the mass spectrum of [3]TFBZ-[2]SBF, (b) is the mass spectrum of [4]TFBZ-[3]SBF, (c) is the mass spectrum of G[2]SBF-TFBZ, (d) is the mass spectrum of G[3]SBF-TFBZ, (e) is the superposition of the NMR spectrum of [3]TFBZ-[2]SBF and G[2]SBF-TFBZ, and (f) is the superposition of the NMR spectrum of [4]TFBZ-[3]SBF and G[3]SBF-TFBZ.

[0033] Figure 2 Figures 1 and 2 are the photophysical characterization diagrams of the present invention. (a) is the spectrum of [3]TFBZ-[2]SBF, [4]TFBZ-[3]SBF, G[2]SBF-TFBZ and G[3]SBF-TFBZ in solution; (b) is the spectrum of [3]TFBZ-[2]SBF, [4]TFBZ-[3]SBF, G[2]SBF-TFBZ and G[3]SBF-TFBZ in thin film; (c) is the spectrum of [3]TFBZ-[2]SBF, [4]TFBZ-[3]SBF, G[2]SBF-TFBZ and G[3]SBF-TFBZ in thin film. Photoluminescence quantum efficiency (PLQY) of FBZ-[2]SBF, [4]TFBZ-[3]SBF, G[2]SBF-TFBZ and G[3]SBF-TFBZ in thin films; (d) is the fluorescence lifetime of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF in different states; (e) is the fluorescence lifetime of G[3]SBF-TFBZ and [4]TFBZ-[3]SBF in different states.

[0034] Figure 3 These are the electrochemical test CV diagrams of the present invention, (a) is the electrochemical oxidation and reduction performance diagram of [3]TFBZ-[2]SBF, [4]TFBZ-[3]SBF, G[2]SBF-TFBZ and G[3]SBF-TFBZ; (b) is the energy level diagram of [3]TFBZ-[2]SBF, [4]TFBZ-[3]SBF, G[2]SBF-TFBZ and G[3]SBF-TFBZ.

[0035] Figure 4The following are the test results of the corresponding evaporated OLED devices of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF: (a) EL spectra of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF; (b) external quantum efficiency EQE of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF; (c) JVL curve of G[2]SBF-TFBZ; (d) relationship between CE and PE of G[2]SBF-TFBZ and current density; (e) JVL curve of [3]TFBZ-[2]SBF; (f) relationship between CE and PE of [3]TFBZ-[2]SBF and current density. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention and the accompanying drawings are further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0037] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the art can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be obtained commercially.

[0038] All raw materials and reagents used in the present invention, including 2,2'-dibromo-9,9'-spirobifluorene (DBrSBF), 1,2,4,5-tetrafluorobenzene, di-tert-butylmethylphosphine tetrafluoride (PtBu2Me-HBF4), palladium acetate (Pd(OAc)2), potassium carbonate (K2CO3), N,N'-dimethylacetamide (DMF), PEDOT:PSS and other drugs or solvents were purchased from Anage, Leyan, McLean, Aladdin or Sinopharm Group. All drugs and solvents were used directly without other treatment after purchase. All experiments carried out in Schlenk reaction tubes were completed in the glove box. All reactions were guaranteed to be carried out under nitrogen environment.

[0039] Example 1

[0040] [n+1]TFBZ-[n]SBF

[0041] The reaction equation of the product ([n+1]TFBZ-[n]SBF) is as follows:

[0042]

[0043] All instruments needed for the reaction, including Schlenk reaction flasks and magnets, were cleaned in advance and placed in an oven for drying. First, the reaction flask was fixed on an iron stand and wrapped with tin foil to ensure light protection. Then, the solid drugs DBrSBF (0.170 g, 1 equiv), K2CO3 (0.276 g, 2 equiv), P t Bu2Me-HBF4 (0.018g, 0.2equiv) and Pd(OAc)2 (0.008g, 0.1equiv), 1,2,4,5-tetrafluorobenzene (0.16ml, 4equiv) and solvent DMAc (20ml) were drawn into the reaction tube with a syringe. After all the reactants and solvents were added, the reaction device was evacuated and nitrogen-filled, and the process was repeated three times. The stopper was tightened under nitrogen to prevent leakage. Finally, the device was transferred to an oil bath, the temperature was set to 120°C, and the reaction was terminated after condensation and reflux for 48h. After the reaction was cooled to room temperature, ethyl acetate / water was used for multiple extractions to remove the high-boiling-point solvent DMAc. The sample was mixed using a rotary evaporator, separated and purified using a 30 cm high chromatography column loaded with 100-200 mesh silica gel powder, and eluted with an eluent with a polarity of [petroleum ether: dichloromethane = 8:1] to obtain solid products [2]TFBZ-SBF, [3]TFBZ-[2]SBF and [4]TFBZ-[3]SBF with yields of 40%, 26% and 23%, respectively.

[0044] Example 2

[0045] [2]TFBZ-SBF

[0046]

[0047] 1 H NMR (400MHz, CDCl3): δ7.95 (d, J = 7.9 Hz, 2H), 7.88 (d, J = 7.6 Hz, 2H), 7.48 (d, J = 8.0 Hz, 2H), 7.40 (t,J=7.5Hz,2H), 7.17(t,J=7.5Hz,2H), 7.01–6.91(m,2H), 6.86(s,2H), 6.81(d,J=7.6Hz,2H); 13 C NMR (101MHz, CDCl3) δ147.6,147.5,141.7,139.8,128.9,127.5,127.0,125.7,124.8,123.1,123.1,119.4,119.1,103.7,103.5,103.3.

[0048] Example 3

[0049] [3]TFBZ-[2]SBF:

[0050]

[0051] 1 H NMR (400MHz, CDCl3): δ7.92 (dd, J=8.0, 4.7Hz, 2H), 7.86 (d, J=7.7Hz, 2H), 7.45 (t, J=7.6Hz, 2 H), 7.39(d,J=7.9,4.1,1.9Hz,2H), 7.20–7.11(m,2H), 7.01–6.86(m,2H), 6.85–6.75(m,4H); 13 C NMR (101MHz, CDCl3) δ147.5,147.5,141.7,141.6,139.9,139.8,128.9,127.5,127.0,124.9,124.8,123.1,119.4,119.1,103.5,96.2,85.4.

[0052] Example 4

[0053] [4]TFBZ-[3]SBF:

[0054]

[0055] 1 H NMR (400MHz, CDCl3): δ7.88–7.74(m,12H), 7.40–7.25(m,12H), 7.15(dt,J=12.0,7. 3Hz,4H), 6.85(ddt,J=10.7,8.6,4.4Hz,2H), 6.97–6.89(m,2H), 6.77–6.67(m,10H); 13 C NMR (101MHz, CDCl3) δ147.6,147.5,141.7,141.6,139.9,139.8,139.8,128.9, 127.5,127.5,127.0,125.7,124.8,123.1,123.1,119.4,119.4,119.1,103.5.

[0056] Example 5

[0057] The reaction equation of the product (G[2]SBF-TFBZ) is as follows:

[0058]

[0059] All instruments required for the reaction, including the Schlenk reaction flask and magnet, were cleaned in advance and placed in an oven for drying. First, the reaction flask was fixed on an iron stand and the device was wrapped with tin foil to ensure light protection. Accurately weigh the solid drugs [2] TFBZ-SBF (0.123 g, 1 equiv), DBrDSBF (0.095 g, 1 equiv), K2CO3 (0.070 g, 2 equiv), P t Bu2Me-HBF4 (0.010 g, 0.2 equiv) and Pd(OAc)2 (0.004 g, 0.1 equiv) were added, and DMAc (20 ml) was drawn by a syringe and added to the reaction tube. After all the drugs were added, the device was evacuated and nitrogen-filled, and the process was repeated three times. The stopper was tightened under nitrogen. Finally, the device was transferred to an oil bath, the temperature was set to 120°C, and the reaction was terminated after condensation and reflux for 48 hours. After the reaction was cooled to room temperature, ethyl acetate / water was used for extraction. Then, the sample was mixed using a rotary evaporator, and separated and purified using a 25 cm high chromatography column loaded with 200-300 mesh silica gel powder. The solid product G[2]SBF-TFBZ was obtained with a yield of 20%. 1 H NMR (400MHz, CDCl3): δ7.97 (d, J = 8.1Hz, 1H), 7.95–7.91 (m, 1H), 7.89–7.80 (m, 4H), 7 .45(tt,J=9.2,1.3Hz,2H), 7.41–7.30(m,4H), 7.17–7.07(m,6H), 6.83–6.74(m,6H); 13 C NMR (101MHz, CDCl3): δ147.9,147.3,147.3,147.3,147.2,146.9,140.4,140.4,139.6,139.5,13 9.5,128.6,128.4,127.3,127.1,126.8,126.6,126.5,124.6,122.8,119.1,119.0,118.8,118.7.

[0060] Example 6

[0061] G[3]SBF-TFBZ

[0062] The reaction equation of the product (G[3]SBF-TFBZ) is as follows:

[0063]

[0064] All instruments required for the reaction, including the Schlenk reaction bottle and the magnet, were cleaned in advance and placed in an oven for drying. First, the reaction bottle was fixed on an iron stand and wrapped with tin foil to ensure light protection. Then, the solid drugs [3]TFBZ-[2]SBF (0.430 g, 1 equiv), DBrSBF (0.188 g, 1 equiv), K2CO3 (0.190 g, 2 equiv), P t Bu2Me-HBF4 (0.020g, 0.2equiv) and Pd(OAc)2 (0.008g, 0.1equiv) were added, and then the solvent DMAc (20ml) was drawn with a syringe and added to the reaction tube. After all the drugs and solvents were added to the reaction tube, the device was evacuated and nitrogen-filled, and the process was repeated three times. The stopper was tightened under nitrogen. Finally, the device was transferred to an oil bath, the temperature was set to 110°C, and the reaction was terminated after condensation and reflux for 48h. After the reaction was cooled to room temperature, ethyl acetate / water was used for extraction. Then the sample was mixed using a rotary evaporator, and a 35cm high chromatography column with 200-300 mesh silica gel powder was used for separation and purification, and an eluent with a polarity of [petroleum ether: dichloromethane = 10:1] was used for elution. After eluting the unreacted substrate, the polarity of the eluent was adjusted to [petroleum ether: dichloromethane = 6:1], and the product was rinsed multiple times to obtain a slightly yellow solid product G[3]SBF-TFBZ with a yield of 5%. 1 HNMR (400MHz,CDCl3): 1 HNMR (400MHz, CDCl3): δ7.94(dd,J=11.9,8.0Hz,3H), 7.89–7.81(m,6H), 7.56–7.51(m,3H), 7.44(d,J=7.9Hz,3H), 7.40–7.32 (m,6H), 7.13(dd,J=8.3,3.0Hz,9H), 7.08(d,J=7.7Hz,3H), 6.88(d,J=17.8Hz,3H), 6.83–6.77(m,3H), 6.69(d,J=7.7Hz,3H).

[0065] Application Example 1

[0066] The specific preparation and characterization process of OLED devices by vacuum evaporation is as follows:

[0067] It is also necessary to clean the ITO-glass substrate in an ultrasonic cleaner in advance, and then put it into an oven at 120°C and dry it for 2 hours for use. First, the ITO-glass substrate was treated with ozone UV for 10 minutes, and then a 10nm thick HAT-CN layer, a 50nm TAPC layer, a 5nm TcTa layer, and a 5nm mCP layer were prepared by vacuum evaporation at a vacuum degree of 1×10-4mbar. Then, the vacuum evaporation process was also used at a temperature of 130°C and a speed of 1A·s -1 The G[2]SBF-TFBZ and [3]TFBZ-[2]SBF films were prepared at a deposition rate of about 20 nm. Finally, a 5 nm thick PPF layer, a 40 nm TPBi layer, a 1 nm LiF layer, and a 100 nm Al layer were evaporated.

[0068] Vacuum evaporation technology is used to prepare OLED.

[0069] The specific device structure is ITO as anode, HAT-CN as hole transport layer, TAPC / TcTa / mCP as injection layer, G[2]SBF-TFBZ and [3]TFBZ-[2]SBF as light-emitting layers, PPF as injection layer, TPBi as electron transport layer, LiF as hole blocking layer, and Al as cathode. The test results are as follows:

[0070] according to Figure 4 a The results show that: EL spectra of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF, the inner inset is a photo of the corresponding device lit up under voltage drive. It can be seen from the figure that the maximum emission wavelengths of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF are 417nm and 444nm respectively, and the linear molecule [3]TFBZ-[2]SBF has a "green band phenomenon".

[0071] according to Figure 4 b The results show that the EQEmax of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF are 1.85% and 0.41%, respectively.

[0072] according to Figure 4 c and Figure 4 The results show that: JVL curves of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF. The turn-on voltage of G[2]SBF-TFBZ is 3.9V, and the brightness reaches the maximum value at 17.0V, with a maximum brightness of 380.7cd·m -2 , corresponding to a current density of 197.1 mA cm -2The start-up voltage of [3]TFBZ-[2]SBF is 4.3V, and the maximum brightness can reach 363.3cd·m at 16.6V. -2 , corresponding to a current density of 187.3 mA cm -2 .

[0073] according to Figure 4 The results of d and 4f show that: they are the relationship between their CE and PE as a function of current density. The maximum current efficiency of G[2]SBF-TFBZ and [3]TFBZ-[2]SBF is 2.7 cd·A -1 and 0.59cd·A -1 , and the corresponding maximum power efficiency is 1.68lm·W -1 and 0.32lm·W -1 .

[0074] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A spirofluorene-based aromatic fluorescent material, the specific molecular formula of the fluorescent material is shown in formula (I), and the general molecular formula is shown in formula (II): in: It is a type of spirofluorene compound; Select any one of the following structures: Select any one of the following structures: X is selected from any one of F, Cl, Br, I, CH3, NO2, and CH3O.

2. The spirofluorene-based aromatic fluorescent material according to claim 1, wherein: The spirofluorene compound The specific structure is as follows:

3. A method for preparing the spirofluorene-based aromatic fluorescent material according to claim 1 or 2, comprising: Weigh the solid drug type I synthon [2] TFBZ-SBF 0.123 g, dibromospirobifluorene DBrDSBF 0.095 g, potassium carbonate K2CO3 0.070 g, ligand tri-tert-butylphosphine tetrafluoroborate P t Bu2Me-HBF40.010 g and Pd(OAc)20.004 g were added, and 20 ml of DMAc was drawn into the reaction tube using a syringe; After all the drugs were added, the device was evacuated and nitrogen-filled for three times, and the plug was tightened under nitrogen. Finally, the device was transferred to an oil bath, the temperature was set to 120°C, and the reaction was terminated after condensation and reflux for 48 hours. After the reaction was cooled to room temperature, it was extracted with ethyl acetate / water, and then mixed using a rotary evaporator. The product was separated and purified using a 25 cm high chromatography column loaded with 200-300 mesh silica gel powder and eluted with an eluent of [petroleum ether: dichloromethane = 8:1] to obtain a solid product G[2]SBF-TFBZ.

4. The preparation method according to claim 3, wherein: The base is selected from: potassium hydroxide, sodium carbonate, sodium bicarbonate or a combination of two thereof; The ligand is selected from: one or a combination of two of PtBu2Me-HBF4, phosphoramidite ligands, 1,1'-binaphthyl-2,2'-bisdiphenylphosphine, and JosiPhos; The organic solvent is selected from: one or a combination of N,N-dimethylacetamide, dimethyl sulfoxide, toluene, and acetonitrile; The palladium catalyst is selected from the group consisting of: tetrakis(triphenylphosphine)palladium, palladium acetate, palladium pivalate, palladium trifluoroacetate, diphenylphosphinocenepalladium dichloride, dichlorobistriphenylphosphine palladium, or palladium-carbon or a combination thereof.

5. The preparation method according to claim 4, wherein: The ligand is PtBu2Me-HBF4; The organic solvent is N,N-dimethylacetamide; The palladium catalyst is palladium acetate.

6. The preparation method according to claim 3, wherein: The amount of the palladium catalyst substance is 0.025 to 0.05 times that of the synthon.

7. The preparation method according to claim 3, wherein: The reaction temperature is 120°C, the reaction time is 48h, and the reaction concentration is 10mmol·L -1 .

8. A spirofluorene-based aromatic fluorescent material prepared according to the preparation method according to any one of claims 3 to 7.

9. Use of the spirofluorene-based aromatic blue light material according to any one of claims 1, 2, and 8 in the preparation of an electroluminescent device.

10. The use according to claim 9, wherein: The electroluminescent device is an organic light emitting diode.

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