Organic fluorescent dye compound as well as preparation method and application thereof

Abstract

The invention relates to the technical field of high-sensitivity Ag < + > fluorescent molecular probes, in particular to an organic fluorescent dye compound as well as a preparation method and application thereof. The structure (DFTA-DPA) provided by the invention can specifically identify Ag < + > and has extremely high sensitivity. The prepared organic fluorescent dye compound with the central symmetry structure has high thermal stability, chemical stability and high fluorescence intensity, and can be used for metal ion responsive luminescent materials, anti-counterfeiting materials and the like. The raw materials for preparing the compound are relatively low in cost, the synthesis method is simple, and industrial production is facilitated. .

Description

Technical Field

[0001] This invention relates to highly sensitive Ag + The field of fluorescent molecular probe technology, particularly an organic fluorescent dye compound, its preparation method, and its application. Background Technology

[0002] Most silver ion recognition probes currently studied both domestically and internationally suffer from limitations in achieving real-time or in-situ monitoring, are susceptible to interference from other heavy metal ions in actual samples, and lack certified reference materials for extremely low concentrations of standard substances, making them difficult to directly apply to complex biological and environmental matrices. The goal is to specifically distinguish a highly sensitive metallic silver ion (Ag...) + The development of probes for [the study of] ... Summary of the Invention

[0003] In view of this, the present invention provides an organic fluorescent dye compound, its preparation method, and its application. The organic fluorescent dye compound provided by the present invention can specifically recognize Ag. + It also has extremely high sensitivity.

[0004] This invention provides an organic fluorescent dye compound having the structure shown in formula DFTA-DPA: .

[0005] The present invention also provides the organic fluorescent dye compound described in the above technical solution, comprising the following steps: S1. Under a protective gas, a solution of 9,10-dibromoanthracene, a thiophene compound, a first palladium catalyst, a first basic compound, and a first solvent are mixed and subjected to a first Suzuki coupling reaction to obtain intermediate product 1. S2. The intermediate product 1, furan compound, second palladium catalyst, solution of second basic compound and second solvent are mixed and subjected to second Suzuki coupling reaction to obtain intermediate product 2. S3. The intermediate product 2 and the aromatic diamine compound are subjected to a Schiff base reaction in an alcohol solvent under heating conditions to obtain the organic fluorescent dye compound.

[0006] Preferably, the thiophene compound is 5-aldehyde-2-thiopheneboronic acid or 4-aldehyde-2-thiopheneboronic acid; the furan compound is furan-2-boronic acid or furan-3-boronic acid; the first palladium catalyst and the second palladium catalyst are independently one or more of Pd(PPh3)4, PdCl2(dppf)2, Pd(dppf)Cl2 and Pd(OAc)2; the first basic compound or the second basic compound is independently one or more of Na2CO3, Ba(OH)2, K3PO4, Cs2CO3, K2CO3, TiOH, KF, CsF, TBAF, NaOH and diethylisopropylamine; the first solvent and the second solvent are independently one or more of THF, CH2Cl2, DMF, NaOH and CH3CN.

[0007] Preferably, in step S1, the molar ratio of 9,10-dibromoanthracene compound to thiophene compound is 1:1~2; the first palladium catalyst is 1~5 mol of the total reactants.

[0008] Preferably, in step S2, the molar ratio of intermediate product 1 to furan-2-boronic acid is 1:1~2; the molar volume ratio of intermediate product 1, the solution of the second basic compound, and the second solvent is 1~100 mmol:60~120 mL:80~250 mL.

[0009] Preferably, the temperature of the first Suzuki coupling reaction or the second Suzuki coupling reaction is independently 80~90°C; and the time of the first Suzuki coupling reaction or the second Suzuki coupling reaction is 11~13 h.

[0010] Preferably, the alcohol solvent is CH3OH and / or C2H5OH; the aromatic diamine compound is o-phenylenediamine or m-phenylenediamine.

[0011] Preferably, the Schiff base reaction is carried out at a temperature of 50-80 °C for 4-12 h.

[0012] Preferably, the concentration of the solution of the first alkaline compound or the solution of the second alkaline compound is 1~10 mol / L.

[0013] This invention also provides the application of the organic fluorescent dye compounds described in the above technical solutions or the organic fluorescent dye compounds prepared by the above preparation methods in organic optoelectronic materials or biochemical detection.

[0014] This invention utilizes a 9,10-diarylanthracene (DSA) molecule with anthracene as its core skeleton, inheriting the strong fluorescence and high stability of anthracene's rigid conjugated structure. Furthermore, it optimizes molecular aggregation behavior through five-membered heterocyclic substituents to enhance the self-assembly induced effect (AIE). Its simple molecular structure and convenient synthesis process reduce production costs and facilitate practical applications. The introduction of heterocyclic units such as furan and thiophene further enhances performance: in specific molecular configurations, the lone pairs of electrons on oxygen and sulfur atoms form stable coordination bonds with metal ions, triggering the spectral response through a conformational change mechanism. The electron-rich five-membered aromatic ring modulates the molecular frontier orbital energy levels through intramolecular charge transfer (ICT) effects, thereby significantly enhancing the detection sensitivity of the spectral signal.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The structure provided by this invention can specifically identify Ag. + It also has extremely high sensitivity.

[0016] The organic fluorescent dye compound with a centrosymmetric structure prepared by this invention exhibits high thermal stability, chemical stability, and strong fluorescence intensity, and can be used in metal ion-responsive luminescent materials, anti-counterfeiting materials, etc. The raw materials for preparing this compound are relatively inexpensive, and the synthesis method is simple, which is beneficial for industrial production. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly described below.

[0018] Figure 1 The proton NMR spectrum of the compound DFTA-DPA prepared in Example 1; Figure 2 The carbon spectrum of the compound DFTA-DPA prepared in Example 2; Figure 3 In the image, (A) is the ultraviolet absorption spectrum of compound DFTA-DPA, (B) is the fluorescence emission spectrum of compound DFTA-DPA, and (C) is the fluorescence image of compound DFTA-DPA at 365 nm ultraviolet wavelength in different solvents. Figure 4 In the diagram, (A) is the absorption spectrum of compound DFTA-DPA in pure tetrahydrofuran and in the solid state, (B) is the fluorescence spectrum in pure tetrahydrofuran and in the solid state, and (C) is the fluorescence decay curve of the compound in pure tetrahydrofuran, aggregated state (fw = 90%), and solid state. Figure 5In the image, (A) is the absorption spectrum of compound DFTA-DPA in different THF / H2O mixtures, (B) is the fluorescence spectrum of compound DFTA-DPA in different THF / H2O mixtures, and (C) is a photograph of compound DFTA-DPA under different water content conditions with 365 nm excitation. Figure 6 (A) shows the size distribution of compound DFTA-DPA in the THF / H2O system (fw = 90%), and (B) shows the scanning electron microscope image of compound DFTA-DPA in the THF / H2O system (fw = 90%). Figure 7 In the image, (A) represents DFTA-DPA in THF buffer (C = 2.0 × 10⁻⁶). -5 (A) Ion-selective fluorescence spectrum of DFTA-DPA (mol / L), (B) Response curve of DFTA-DPA fluorescence spectrum with silver ion concentration (inset: fluorescence intensity at 575 nm and silver ion concentration), (C) Experimental photograph of color change after adding different metal ions (10 equivalents). Figure 8 (A) in the figure represents DFTA-DPA in THF (C=2.0×10). -5 Cross-interference analysis in mol / L, (B) is the fluorescence image recovered by EDTA titration after DFTA-DPA binds to silver ions; Figure 9 In the diagram, (A) represents the detection limit analysis, (B) represents the binding constant curve of DFTA-DPA with silver ions (Ag+), and (C) represents the analysis of the binding mode of DFTA-DPA with silver ions. Figure 10 This is a fluorescence fingerprint image of the compound DFTA-DPA. Figure 11 (A) shows the color change on the test strip after the compound DFTA-DPA combines with aqueous solutions of various metal ions under sunlight, and (B) shows the color change on the test strip after the compound DFTA-DPA combines with aqueous solutions of various metal ions under ultraviolet light. Detailed Implementation

[0019] This invention provides an organic fluorescent dye compound having the structure shown in formula DFTA-DPA: .

[0020] The organic fluorescent dye compound provided by this invention has a centrosymmetric structure.

[0021] This invention also provides a method for preparing the organic fluorescent dye compound described in the above technical solution, comprising the following steps: S1. Under a protective gas, a solution of 9,10-dibromoanthracene, a thiophene compound, a first palladium catalyst, a first basic compound, and a first solvent are mixed and subjected to a first Suzuki coupling reaction to obtain intermediate product 1. S2. The intermediate product 1, furan compound, second palladium catalyst, solution of second basic compound and second solvent are mixed and subjected to second Suzuki coupling reaction to obtain intermediate product 2. S3. The intermediate product 2 and the aromatic diamine compound are subjected to a Schiff base reaction in an alcohol solvent under heating conditions to obtain the organic fluorescent dye compound.

[0022] In this invention, a solution of 9,10-dibromoanthracene, a thiophene compound, a first palladium catalyst, a first basic compound, and a first solvent are mixed in a protective gas and subjected to a first Suzuki coupling reaction to obtain intermediate product 1; intermediate product 1, a furan compound, a second palladium catalyst, a solution of a second basic compound, and a second solvent are mixed and subjected to a second Suzuki coupling reaction to obtain intermediate product 2.

[0023] In this invention, the thiophene compound can be 5-aldehyde-2-thiopheneboronic acid or 4-aldehyde-2-thiopheneboronic acid, preferably 5-aldehyde-2-thiopheneboronic acid; the furan compound can be furan-2-boronic acid or furan-3-boronic acid, preferably furan-2-boronic acid.

[0024] In this invention, the first palladium catalyst and the second palladium catalyst can independently be one or more of Pd(PPh3)4, PdCl2(dppf)2, Pd(dppf)Cl2 and Pd(OAc)2, preferably Pd(PPh3)4, Pd(dppf)Cl2 and Pd(OAc)2, and more preferably Pd(PPh3)4 and / or Pd(OAc)2.

[0025] In this invention, the concentration of the solution of the first alkaline compound or the solution of the second alkaline compound can be 1~10 mol / L, preferably 2~8 mol / L, and more preferably 4~6 mol / L; the first alkaline compound or the second alkaline compound can independently be one or more of Na2CO3, Ba(OH)2, K3PO4, Cs2CO3, K2CO3, TiOH, KF, CsF, TBAF, NaOH, and diethylisopropylamine, preferably one or more of Na2CO3, Ba(OH)2, K3PO4, Cs2CO3, K2CO3, TiOH, KF, NaOH, and diethylisopropylamine, and more preferably ... The solvent is selected from one or more of OH)2, K3PO4, K2CO3, KF, NaOH, and diethylisopropylamine; the protective gas can be nitrogen, argon, or neon, preferably nitrogen or argon, and more preferably nitrogen; the first solvent and the second solvent can independently be selected from one or more of THF, CH2Cl2, DMF, NaOH, and CH3CN, preferably one or more of THF, DMF, NaOH, and CH3CN, and more preferably one or more of THF, DMF, and CH3CN.

[0026] In this invention, in step S1, the molar ratio of 9,10-dibromoanthracene compound and thiophene compound can be 1:1~2, preferably 1:1.2~1.8, and more preferably 1:1.4~1.6; the first palladium catalyst is 1~5 mol% of the total reactants, preferably 1~4 mol%, and more preferably 2 mol%; the molar volume of the solution of thiophene compound, the first basic compound, and the first solvent is 1~100 mmol: 60~120 mL: 80~250 mL, and more preferably 10~50 mmol: 80~100 mL: 150~200 mL.

[0027] In this invention, in step S2, the molar ratio of intermediate product 1 and furan-2-boronic acid can be 1:1~2, preferably 1:1.2~1.8, and more preferably 1:1.4~1.6; the molar volume ratio of intermediate product 1, the solution of the second basic compound, and the second solvent can be 1~100 mmol:60~120 mL:80~250 mL, and more preferably 10~50 mmol:80~100 mL:150~200 mL.

[0028] In this invention, the temperature of the first Suzuki coupling reaction or the second Suzuki coupling reaction is independently 80~90 °C, preferably 82~86 °C, and more preferably 85 °C; the time of the first Suzuki coupling reaction or the second Suzuki coupling reaction is 11~13 h, preferably 11.5~12.5 h, and more preferably 12 h.

[0029] In this invention, after the first Suzuki coupling reaction, it is preferable to further include cooling the reaction product to room temperature and then removing the solvent by rotary evaporation to obtain a rotary evaporation residue; extracting the rotary evaporation residue, drying and filtering the resulting organic phase sequentially to obtain a filtrate, and separating the filtrate by column chromatography to obtain intermediate product 1.

[0030] In this invention, after the second Suzuki coupling reaction is completed, the reaction product is cooled to room temperature and the solvent is removed by rotary evaporation to obtain a rotary evaporation residue; the rotary evaporation residue is extracted, and the obtained organic phase is dried and filtered in sequence to obtain a filtrate; the filtrate is separated by column chromatography to obtain intermediate product 2.

[0031] In this invention, the extractant used for the first Suzuki coupling reaction and the extraction following the second Suzuki coupling reaction is preferably dichloromethane; the drying agent used for the drying is preferably anhydrous magnesium sulfate; and the eluent used for the column chromatography separation is preferably petroleum ether.

[0032] In this invention, intermediate product 2 and an aromatic diamine compound are subjected to a Schiff base reaction in an alcohol solvent under heating conditions to obtain the organic fluorescent dye compound.

[0033] In this invention, the alcohol solvent can be CH3OH and / or C2H5OH. In this invention, the aromatic diamine compound can be o-phenylenediamine or m-phenylenediamine, preferably o-phenylenediamine.

[0034] In this invention, the temperature of the Schiff base reaction is 50~80 ℃, preferably 60~75 ℃, more preferably 60~70 ℃; the time is 4~12 h, preferably 5~11 h, more preferably 8 h.

[0035] In this invention, after the Schiff base reaction is completed, it is preferable to further cool the reaction product to room temperature and then sequentially filter, wash and dry it to obtain the residue; the residue is then separated by column chromatography to obtain the organic fluorescent dye compound.

[0036] In this invention, the drying agent used for drying is preferably anhydrous magnesium sulfate; the eluent used for column chromatography separation is preferably a mixture of petroleum ether and ethyl acetate, and the volume ratio of petroleum ether to ethyl acetate is preferably 5~8:1, more preferably 6~7:1.

[0037] In this invention, the preparation equation for the organic fluorescent dye compound is as follows: .

[0038] This invention also provides the application of the organic fluorescent dye compounds described in the above technical solutions or the organic fluorescent dye compounds prepared by the above preparation methods in organic optoelectronic materials and biochemical detection.

[0039] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the accompanying drawings and embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0040] Example 1 Under argon protection, 9,10-dibromosulfanilamide (1.2 g, 3.6 mmol) was dissolved in a three-necked flask containing an appropriate amount of tetrahydrofuran solvent and stirred for 30 minutes. Then, 5-aldehyde-2-thiopheneboronic acid (0.56 g, 3.6 mmol), Pd(PPh3)4 (0.05 g, 0.043 mmol), and sodium carbonate solution (2.0 mol / L, 60.0 mL) were added, and the mixture was heated under reflux for 12 h. After the reaction was complete, the tetrahydrofuran solvent was evaporated, and the resulting mixture was extracted twice with dichloromethane. The organic phases were combined, washed successively with saturated brine and purified water, and dried over anhydrous sodium sulfate for 12 h. Dichloromethane solvent was removed by rotary evaporation under reduced pressure. The resulting mixture was purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate (v / v = 8:1) as the eluent to obtain a yellow solid compound 1 (0.78 g, 2.05 mmol), with a yield of 57%, and was named intermediate 1.

[0041] Under argon protection, a mixture of intermediate 1 (3.00 g, 8.20 mmol) and furan-2-ylboronic acid (1.00 g, 8.20 mmol) was dissolved in anhydrous tetrahydrofuran (80.0 mL). Pd(PPh3)4 (0.05 g, 0.043 mmol) and an aqueous solution of Na2CO3 (2.0 mol / L, 40.0 mL) were added to this solution. The reaction mixture was refluxed under vigorous stirring for 12 h. After cooling to room temperature, the product was extracted with dichloromethane (3 × 50 mL). The combined organic layers were dried over anhydrous MgSO4, filtered, and concentrated under reduced pressure. Purification by silica gel column chromatography with petroleum ether / ethyl acetate (v / v = 6:1) as eluent gave intermediate 2 (2.34 g, 80% yield), a bright yellow crystalline solid.

[0042] In a dry flask, compound 2 (0.80 g, 2.26 mmol) and o-phenylenediamine (0.12 g, 1.13 mmol) were dissolved in 20 mL of CH3OH solution. After heating under reflux at 60 °C for 8 h, the mixture was cooled and concentrated under vacuum. Purification by silica gel column chromatography (petroleum ether / ethyl acetate v / v = 4:1) yielded compound DFTA-DPA as a yellow amorphous solid (0.32 g, 36% yield).

[0043] Figures 1-2 The proton and carbon spectra of the compound DFTA-DPA prepared in this embodiment provide the following spectral information: 1 H NMR (400 MHz, CDCl3): δ (ppm) 8.61 - 8.56 (m, 4H), 7.95 - 7.79 (m,8H), 7.63 - 7.53 (m, 6H), 7.43 - 7.28 (m, 10H), 7.16 (d, J = 4.0 Hz, 1H), 7.05(d, J = 4.0 Hz, 1H), 5.98 (s, 2H). 13 C NMR (101 MHz, CDCl3) δ 147.24, 143.08,142.63, 140.19, 139.21, 136.04, 133.42, 132.34, 130.66, 130.19, 129.81,128.70, 128.43, 127.94, 127.18, 127.12, 126.79, 126.43, 126.37, 126.25,125.94, 125.12, 124.86, 123.67, 123.29, 120.18, 109.95.

[0044] Figure 3 In the diagram, (A) is the UV absorption spectrum of compound DFTA-DPA, (B) is the fluorescence emission spectrum of compound DFTA-DPA, and (C) is the fluorescence image of compound DFTA-DPA at 365 nm UV wavelength in different solvents. Figure 3It can be seen that the absorption peak of the molecule shifts with the change of solvent polarity, indicating that its ground-state dipole moment is small, resulting in a decrease in the molecule's sensitivity to polar environments. In contrast, the photoluminescence spectrum shows a significant blue shift in the fluorescence emission wavelength (from 601 nm in n-hexane to 506 nm in DMSO) with increasing solvent polarity, and the color gradually changes from bright yellow to pale yellow-green under 365 nm illumination.

[0045] Figure 4 (A) shows the absorption spectrum of compound DFTA-DPA in pure tetrahydrofuran and in the solid state; (B) shows the fluorescence spectrum in pure tetrahydrofuran and in the solid state; and (C) shows the fluorescence decay curves of the compound in pure tetrahydrofuran, in the aggregated state, and in the solid state. Figure 4 It is known that the centrosymmetric structure of the compound DFTA-DPA can induce a significant intramolecular charge transfer (ICT) effect. However, the strongly coupled aggregates formed in the solid state may affect fluorescence quenching. These effects collectively explain the pronounced Stokes shift observed in pure tetrahydrofuran (THF) and in the solid state, as well as the decrease in emission intensity. Figure 4 The fluorescence decay curves of compound DFTA-DPA in tetrahydrofuran and the solid state are presented. Of particular note is the fluorescence lifetime of 0.31 nm in tetrahydrofuran, 0.35 nm in a THF / H₂O mixture containing 90% water, and a remarkable 0.88 nm in the solid state. The prolonged fluorescence lifetime observed in the solid state indicates that non-radiative decay pathways are suppressed—the rigid matrix restricts molecular vibration / rotation and reduces internal conversion processes. The reduced solute collisions in the solid phase effectively mitigate the fluorescence quenching effect. Furthermore, enhanced intermolecular interactions (such as π-π stacking or excitocomplex formation) result in a redshift of the emission wavelength of newly excited states.

[0046] Figure 5 (A) shows the absorption spectrum of compound DFTA-DPA in different THF / H2O mixtures; (B) shows the fluorescence spectrum of compound DFTA-DPA in different THF / H2O mixtures; (C) shows photographs of compound DFTA-DPA under different water contents with 365 nm excitation. Figure 5 It can be seen that, with water content (f) w The evolution of the fluorescence spectrum is increased. When f w When the emission level is below 40%, the emission intensity remains relatively stable; subsequently at f w = Slightly enhanced in the range of 50~70%, and in f wThe fluorescence intensity peaks at 80%. Simultaneously, a redshift to 521 nm is observed, and the color changes from pale yellow to bright yellow-green. These characteristic spectral changes and color shifts indicate that with increasing water content, molecules transition from a monodisperse state to an aggregated state (where the polarity and hydrophobicity of water molecules jointly drive molecular aggregation). This process suppresses nonradiative transitions within the molecules, allowing more excited molecules to return to the ground state via radiative transitions (luminescence), thus enhancing fluorescence intensity. Simultaneously, during molecular aggregation, intermolecular π-π conjugation is strengthened, expanding the electronic delocalization range of the entire conjugated system. This broader electronic delocalization leads to a smaller bandgap, corresponding to the redshift in emission wavelength.

[0047] Figure 6 The size distribution (f) of compound DFTA-DPA in the THF / H2O system. w = 90%), (B) is a scanning electron microscope image of compound DFTA-DPA in the THF / H2O system (f w = 90%). By Figure 6 These results demonstrate that this 9,10-diarylanthracene-based derivative forms a dense molecular structure during self-assembly. The formation of such fluorescent nanoaggregates provides a simple and effective method for developing AIE active probes, highlighting their broad prospects in biological detection and practical applications.

[0048] Figure 7 (A) shows the ion-selective fluorescence spectrum of compound DFTA-DPA in THF, and (B) shows the ion-selective fluorescence spectrum of compound DFTA-DPA for different concentrations of Ag. + Fluorescence spectrum changes (inset: fluorescence intensity at 575 nm as a function of Ag) + (C) shows the effect of DFTA-DPA on Ag concentration changes and corresponding visual fluorescence changes. + Images taken under selective ultraviolet light. (By...) Figure 7 It can be seen that the probe is effective against silver ions (Ag). + ) exhibits significant selectivity for Co 2+ Sr 2+ Cr 2+ Fe 3+ Al 3+ Fe 2+ Ca 2+ Pt 2+ Mg 2+ Ni 2+ Cd 2+ Sn 2+ Zn 2+ Cu 2+ Na + Pb2+ and Ba 2+ Other metal ions (each 10.0 equivalent) showed no significant response.

[0049] Figure 8 In the middle (A), compound DFTA-DPA is in THF (C=2.0×10⁻⁶). -5 Cross-interference analysis in (mol / L), (B) shows the interaction between DFTA-DPA and silver ions (Ag). + The chromatogram was recovered by EDTA titration after the combination of the two compounds. Figure 8 This indicates the presence of Ag. + Even after the addition of interfering metal ions, the emission intensity of compound DFTA-DPA did not change significantly. These results indicate that compound DFTA-DPA has an effect on Ag... + It has high selectivity and is unaffected by potential interference.

[0050] Figure 9 The analysis of the detection limit, binding constant, and complexation ratio with silver ions of compound DFTA-DPA showed that DFTA-DPA has an extremely high sensitivity of up to 10. -10 It is at the nm level and forms a 1:2 bond with silver ions.

[0051] Figure 10 This is a fluorescence fingerprint image of the compound DFTA-DPA. Figure 10 It is evident that the compound DFTA-DPA is used as a fluorescent developer due to its unique yellow-green emission spectrum. Under ultraviolet light irradiation, the system can clearly resolve primary (core ridges), secondary (ridge ends and bifurcations), and tertiary (pore structure and epidermal folds) fingerprint features, confirming the potential of DFTA-DPA as an effective tool for forensic fingerprint identification.

[0052] Figure 11 (A) shows the color change of the test strip after compound DFTA-DPA combines with aqueous solutions of various metal ions under sunlight; (B) shows the color change of the test strip after compound DFTA-DPA combines with aqueous solutions of various metal ions under ultraviolet light. Figure 11 It was found that the probe exhibited a significant fluorescence response under 365 nm ultraviolet light irradiation. The probe contacts Ag... + Immediately after contact with the analyte, a visible color change occurred: the originally yellowish-green test paper rapidly turned pale yellow under sunlight; and under ultraviolet light, the bright blue fluorescence transformed into brownish-yellow emission. These significant color changes occurring within seconds of contact with the analyte confirm that this probe functions as a real-time Ag... + The effectiveness of the paper-based fluorescent probe was monitored.

[0053] Application examples The fluorescent compound DFTA-DPA targets silver ions (Ag) + It exhibits excellent selectivity and sensitivity, with significant contrast and detection limit, making it particularly suitable for on-site testing scenarios. To facilitate practical application, this invention provides a paper probe. The preparation process includes immersing filter paper in tetrahydrofuran (C = 1.0 × 10⁻⁶) containing DFTA-DPA. -3 In mol / L, it was then dried at room temperature. When testing different metal ions (Ag) + Co 2+ Sr 2+ Cr 2+ Fe 3+ Al 3+ Fe 2+ Ca 2+ Pt 2+ Mg 2+ Ni 2 + Cd 2+ Sn 2+ Zn 2+ Cu 2+ Na + Pb 2+ and Ba 2+ When the probe is in a solution (C = 0.1 mol / L), it exhibits a significant fluorescence response under 365 nm ultraviolet light. Upon contact with the silver ion solution, a visible color change occurs immediately: under sunlight, the originally yellowish-green test paper rapidly turns pale yellow; and under ultraviolet light, the bright blue fluorescence transforms into brownish-yellow emission. These significant color changes, occurring within seconds of contact with the analyte, confirm the effectiveness of this paper-based fluorescent probe in real-time silver ion monitoring.

[0054] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. An organic fluorescent dye compound, characterized in that, It has the structure shown in formula DFTA-DPA: 。 2. The organic fluorescent dye compound according to claim 1, characterized in that, Includes the following steps: S1. Under a protective gas, a solution of 9,10-dibromoanthracene, a thiophene compound, a first palladium catalyst, a first basic compound, and a first solvent are mixed and subjected to a first Suzuki coupling reaction to obtain intermediate product 1. S2. The intermediate product 1, furan compound, second palladium catalyst, solution of second basic compound and second solvent are mixed and subjected to second Suzuki coupling reaction to obtain intermediate product 2. S3. The intermediate product 2 and the aromatic diamine compound are subjected to a Schiff base reaction in an alcohol solvent under heating conditions to obtain the organic fluorescent dye compound.

3. The preparation method according to claim 2, characterized in that, The thiophene compound is 5-aldehyde-2-thiopheneboronic acid or 4-aldehyde-2-thiopheneboronic acid; the furan compound is furan-2-boronic acid or furan-3-boronic acid; the first palladium catalyst and the second palladium catalyst are independently one or more of Pd(PPh3)4, PdCl2(dppf)2, Pd(dppf)Cl2 and Pd(OAc)2; the first basic compound or the second basic compound are independently one or more of Na2CO3, Ba(OH)2, K3PO4, Cs2CO3, K2CO3, TiOH, KF, CsF, TBAF, NaOH and diethylisopropylamine; the first solvent and the second solvent are independently one or more of THF, CH2Cl2, DMF, NaOH and CH3CN.

4. The preparation method according to claim 2, characterized in that, In step S1, the molar ratio of 9,10-dibromoanthracene compound to thiophene compound is 1:1~2; the first palladium catalyst is 1~5 mol of the total reactants.

5. The preparation method according to claim 2, characterized in that, In step S2, the molar ratio of intermediate product 1 to furan-2-boronic acid is 1:1~2; the molar volume ratio of intermediate product 1, the solution of the second basic compound, and the second solvent is 1~100 mmol: 60~120 mL: 80~250 mL.

6. The preparation method according to claim 2, characterized in that, The temperature of the first or second Suzuki coupling reaction is independently 80-90 °C; the time of the first or second Suzuki coupling reaction is 11-13 h.

7. The preparation method according to claim 2, characterized in that, The alcohol solvent is CH3OH and / or C2H5OH; the aromatic diamine compound is o-phenylenediamine or m-phenylenediamine.

8. The preparation method according to claim 2, characterized in that, The Schiff base reaction is carried out at a temperature of 50-80 °C for 4-12 h.

9. The preparation method according to claim 2, characterized in that, The concentration of the solution of the first alkaline compound or the solution of the second alkaline compound is 1~10 mol / L.

10. The application of the organic fluorescent dye compound of claim 1 or the organic fluorescent dye compound prepared by the preparation method of any one of claims 2 to 9 in organic optoelectronic materials or biochemical detection.

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