Organic Superfluorescent Scintillators without Heavy Atom Modification, Their Preparation Methods and Applications

Abstract

The present invention belongs to the field of organic light-emitting materials. The present invention discloses an organic hyperfluorescent scintillator material without heavy atom modification and its preparation method. Compared with the commonly used scintillator materials at present, such materials do not require the participation of heavy atoms in the molecular structure design, and have the characteristics of simple preparation and good film-forming property. For the organic hyperfluorescent scintillator material prepared by the present invention, VQA with an amine / carbonyl multiple resonance (MR) chromophore is selected, which is covalently bonded to 4-vinylpyridine. Through the effective energy transfer from 4VP to VQA, high-efficiency radiative luminescence is achieved. At the same time, by using the method of physical blending, the prepared material is doped with some commercial materials, further improving the radiative luminescence performance of the material, providing the possibility for subsequent application in the field of X-ray imaging.

Description

Technical Field

[0001] The present invention belongs to the field of organic light-emitting materials, and particularly relates to a preparation method of an organic hyperfluorescent scintillator without heavy atom modification. Background Art

[0002] Scintillator luminescence is a phenomenon that can convert high-energy X-ray photons into low-energy visible light, showing great potential in fields such as medical treatment, astrophysics, radiochemistry, and industrial non-destructive testing. Organic scintillators have been developed as promising scintillator materials due to their low cost, flexibility, and easy-to-prepare processes.

[0003] However, the limited atomic number of organic materials leads to poor X-ray absorption, and most known organic scintillators are fluorescent materials whose luminescence originates from singlet excited states. In fluorescent organic scintillators, only 25% of singlet excitons are used for radiative luminescence (RL), and 75% of triplet excitons are wasted. Therefore, weak X-ray absorption and inefficient exciton utilization hinder the development and commercialization of organic scintillators. This is because for organic scintillators of traditional fluorescent dyes, the triplet excited states generated by the energy deposition of incident particles can be converted into singlets through triplet-triplet annihilation to achieve the delayed pulse tail characteristics of organic scintillators, but generally it is not a particularly effective triplet-to-singlet conversion process. For example, the most well-known organic scintillator currently is anthracene-based scintillator, but its low exciton utilization rate limits its development in the field of X-ray detection. In this regard, we studied using thermally activated delayed fluorescence materials as the luminescent molecules of organic scintillators and found that a smaller singlet-triplet energy difference is helpful for the luminescence capture of radiation-induced triplet excitons. TADF scintillators have reduced self-absorption due to their large Stokes shift, and their performance is significantly better than anthracene-based scintillators, providing great new possibilities for radiation detection and imaging using efficient organic materials. Summary of the Invention

[0004] To solve the above problems, the present invention discloses an organic hyperfluorescent scintillator material without heavy atom modification and its preparation method. Compared with the currently commonly used scintillator materials, the materials of the present application do not require the participation of heavy atoms in the molecular structure, and have characteristics such as simple preparation and good film-forming property. For the organic hyperfluorescent scintillator material prepared by the present invention, 7-(4-vinylphenyl)quinolino[3,2,1-de]acridine-5,9-dione (VQA) with an amine / carbonyl multiple resonance MR chromophore is selected, and it is covalently bonded with 4-vinylpyridine. Through effective energy transfer from 4VP to VQA, high-efficiency radiative luminescence is achieved. At the same time, by using the method of physical blending, the prepared material is doped with some commercial materials, further improving the radiative luminescence performance of the material, providing the possibility for subsequent application in the X-ray field.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] The present invention provides a heavy-atom-free organic superphosphorescent scintillator, including P4VQA, and its structural formula is as follows:

[0007] Formula I;

[0008] Wherein, m:n = 1:0.005.

[0009] Another object of the present invention is to provide a preparation method of a heavy-atom-free modified organic superphosphorescent scintillator, including the following steps:

[0010] S1. Under an argon atmosphere, dimethyl 5-bromo-2-iodoisophthalate, diphenylamine, activated copper powder, potassium carbonate, and cuprous iodide are dissolved in ortho-dichlorobenzene, and reacted to obtain dimethyl 5-bromo-2-(diphenylamino)propionate;

[0011] S2. Under an argon atmosphere, sodium hydroxide and an ethanol aqueous solution are added to dimethyl 5-bromo-2-(diphenylamino)propionate, and reacted to obtain 5-bromo-2-(diphenylamino)valeric acid;

[0012] S3. Under an argon atmosphere, N,N-dimethylformamide is added to a mixture of 5-bromo-2-(diphenylamino)valeric acid and dichloromethane, and then oxalyl chloride and stannous chloride are added, and reacted to obtain 7-bromoquinolino[3,2,1-de]acridine-5,9-dione;

[0013] S4. Under an argon atmosphere, 7-bromoquinolino[3,2,1-de]acridine-5,9-dione, potassium carbonate, tetrakis(triphenylphosphine)palladium, and 4-vinylbenzeneboronic acid are dissolved in toluene, deionized water is added, and reacted to obtain 7-(4-vinylphenyl)quinolino[3,2,1-de]acridine-5,9-dione (VQA);

[0014] S5. Under an argon atmosphere, VQA, 4-vinylpyridine, and azobisisobutyronitrile are added to toluene, and reacted to obtain a powder product of the organic superphosphorescent scintillator P4VQA.

[0015] Further, in step S1, dimethyl 5-bromo-2-iodoisophthalate, diphenylamine, activated copper powder, and potassium carbonate are added to ultra-dry ortho-dichlorobenzene, and reacted under an argon atmosphere at 175-180 °C for 20-24 h; wherein the molar ratio of dimethyl 5-bromo-2-iodoisophthalate, diphenylamine, activated copper powder, potassium carbonate, and cuprous iodide is 1:1.1-1.2:0.15-0.2:1.3-1.4:0.04-0.05; the molar ratio of dimethyl 5-bromo-2-iodoisophthalate to ortho-dichlorobenzene is 1:157-158.

[0016] Further, in step S2, sodium hydroxide and an ethanol aqueous solution are added, and the reaction is carried out at 75 - 80 °C for 20 - 24 h under an argon atmosphere; where ethanol / water (V / V: 1 / 1); the molar ratio of dimethyl 5-bromo-2-(diphenylamino)valerate to sodium hydroxide is 1:5.

[0017] Further, in step S3, under an ice-water bath, in a mixture of 5-bromo-2-(diphenylamino)valeric acid and dichloromethane, N,N-dimethylformamide is added, and then oxalyl chloride is added dropwise. After removing the ice-water bath and reacting at a temperature of 40 - 45 °C for 30 min, tin chloride is added dropwise and the same temperature is maintained for continued reflux condensation for 3 h;

[0018] Further, the molar ratio of 5-bromo-2-(diphenylamino)valeric acid to oxalyl chloride is 1:2.1 - 2.2, the molar ratio of 5-bromo-2-(diphenylamino)valeric acid to tin chloride is 1:2.1 - 2.2; the molar ratio of 5-bromo-2-(diphenylamino)valeric acid to dichloromethane is 1:500 - 520.

[0019] Further, in step S4, the reaction is carried out at 85 - 90 °C under an argon atmosphere for 20 - 24 h; bubbling operation is required for toluene; the molar ratio of 7-bromoquinolino[3,2,1-de]acridine-5,9-dione to 4-vinylphenylboronic acid is 1:1.4 - 1.5; the molar ratio of 7-bromoquinolino[3,2,1-de]acridine-5,9-dione to potassium carbonate is 1:1.4 - 1.5; the molar ratio of potassium carbonate to tetrakis(triphenylphosphine)palladium is 1:0.032 - 0.033; the molar ratio of 7-bromoquinolino[3,2,1-de]acridine-5,9-dione to toluene (ultra-dry) is 1:42 - 45; the volume ratio of toluene (ultra-dry) to deionized water is 2:1.

[0020] Further, in step S5, the reaction is carried out at 65 - 70 °C under an argon atmosphere for 10 - 12 h; where 4-vinylpyridine needs to remove the stabilizer by vacuum distillation; the molar ratio of 4-vinylpyridine to VQA is 1:0.005; the molar ratio of 4-vinylpyridine to 7-(4-vinylphenyl)quinolino[3,2,1-de]acridine-5,9-dione is 1:0.001 - 0.005; the molar ratio of 4-vinylpyridine to azobisisobutyronitrile is 1:0.01 - 0.015; the molar ratio of 4-vinylpyridine to toluene (ultra-dry) is 1:2.

[0021] The present invention also provides an application of the above-described heavy-atom-free modified organic super-fluorescent scintillator in the field of X-rays.

[0022] The beneficial effects of the present invention are:

[0023] (1) The present invention specifically designs and prepares an organic super-fluorescent scintillator. Compared with the current scintillator materials, it does not contain halogens, is simple to prepare, has good film-forming properties, and can emit green light under ultraviolet excitation in the thin film state.

[0024] (2) During the preparation process of the present invention, there is no need to add harmful substances such as halogens, which greatly reduces the damage to the human body and the environment caused by the reaction. At the same time, the products of the present invention can be prepared on a large scale, and the preparation process is simple, which greatly reduces the preparation cost and is conducive to subsequent entry into the organic scintillator market.

[0025] (3) The present invention utilizes the characteristic of the VQA material having an amine / carbonyl multi-resonant MR chromophore, covalently binds it to 4-vinylpyridine, and uses it as a narrow-band emitter to achieve efficient energy transfer from 4VP to VQA. At the same time, 4VP is used as the host material because its promoted intersystem crossing (ISC) promotes the generation of triplet excitons through effective n-π* transitions and high triplet energy levels, which helps to support efficient energy transfer from the host to the guest to sensitize the triplet excitons of the guest. The above materials provide a new research strategy for the development and design of efficient organic fluorescent scintillators.

[0026] (4) The organic super-fluorescent scintillator material prepared by the present invention selects VQA with an amine / carbonyl multiple resonance MR chromophore, covalently binds it to 4-vinylpyridine, and realizes high-efficiency radiative luminescence through efficient energy transfer from 4VP to VQA. At the same time, by using the method of physical blending, the prepared material is doped with some commercial materials, further improving the radiative luminescence performance of the material, providing the possibility for subsequent application in the field of X-ray imaging. Description of the Drawings

[0027] Figure 1 shows the steady-state spectra of P4VQA at different ratios;

[0028] Figure 2 shows the absorption spectrum of P4VQA in solution state and the steady-state spectra of P4VQA under excitation at different wavelengths;

[0029] Figure 3 shows the ultraviolet excitation spectra of P4VQA (m:n = 1:0.005) physically blended with each guest material and the ultraviolet excitation spectra of P4VQA (m:n = 1:0.005) with different doping ratios with each guest material. Detailed Embodiments

[0030] The following further clarifies the present invention in conjunction with the drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. Example 1

[0031] Synthesis of Dimethyl 5-Bromo-2-(diphenylamino)propionate

[0032] Dimethyl 5-bromo-2-iodoisophthalate (3.93 g, 9.85 mmol), diphenylamine (2.00 g, 11.82 mmol), activated copper (0.13 g, 1.97 mmol), copper(I) iodide (0.09 g, 0.49 mmol), potassium carbonate (1.77 g, 12.80 mmol) and 30 mL of 1,2-dichlorobenzene (o-DCB) were stirred and refluxed for 24 h under an argon atmosphere. After cooling to room temperature, 100 mL of dichloromethane (DCM) was added to the mixture, and then stirred for 10 min. After filtering the mixture through a glass filter funnel, the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography using ethyl acetate (EA) / petroleum ether (PE) (V / V: 1 / 50) as the eluent to obtain the product as a light green solid product, 1 H NMR (400 MHz, CDCl 3 ) δ = 7.86(s, 2H), 7.21-7.17 (m, 4H), 6.97-6.94(m, 6H), 3.45 (s, 6H). 13 C NMR (101 MHz,CDCl 3 ) δ = 166.26, 146.74, 143.57, 136.59, 134.17,129.03, 122.73, 122.55,118.01, 52.56. MALDI-TOF: m / z calcd for C 22 H 18 BrNO 4 [M] + : 440.19; Found:440.29. The structure is as follows:

[0033] 。 Example 2

[0034] Synthesis of 5-Bromo-2-(diphenylamino)pentanoic Acid

[0035] Under an argon atmosphere, dimethyl 5-bromo-2-(diphenylamino)pentanoate (3.50 g, 7.95 mmol) and sodium hydroxide (1.59 g, 39.75 mmol) were added to a solution of ethanol / water (V / V: 1 / 1, 50 mL). The mixture was stirred and refluxed for 24 h. After cooling to room temperature, the precipitate was acidified with concentrated hydrochloric acid to give a yellow solid, which was filtered through a glass filter funnel, washed with deionized water and dried overnight in a vacuum oven. The yellow solid product (yield: 3.11 g, 95%) was used directly without further purification. The structure is as follows:

[0036] . Example 3

[0037] Synthesis of 7-bromoquinolino[3,2,1-de]acridine-5,9-dione

[0038] Under an argon atmosphere, two drops of N,N-dimethylformamide (DMF) were added to a mixture of 5-bromo-2-(diphenylamino)pentanoic acid (2.60 g, 6.31 mmol) in anhydrous DCM (100 mL). After adding oxalyl chloride (1.18 mL, 13.88 mmol), the mixture was refluxed for 30 min. Then, a solution of tin(IV) chloride in DCM (6.94 mL, 2 M, 13.88 mmol) was added and the mixture was refluxed for 3 h. After cooling to room temperature, the mixture was added dropwise to an aqueous solution of 1 M sodium hydroxide and extracted three times with DCM. The organic layer was dried over anhydrous magnesium sulfate. After filtration and evaporation of the solvent, the given residue was purified by silica gel column chromatography using DCM / PE (V / V: 3 / 1) as the eluent to give the product as an orange-yellow solid product, 1 H NMR (400MHz, CDCl 3 ) δ = 8.81 (s, 2H), 8.48 (dd, J = 7.9, 1.7 Hz, 2H), 8.13 (d,J = 8.6Hz, 2H), 7.72 (ddd, J = 8.8, 7.2, 1.7 Hz, 2H), 7.53~7.49 (m, 2H). 13 C NMR (101MHz,CDCl 3 ) δ = 117.97, 140.16, 138.41, 135.60, 133.54, 128.47, 126.79,125.97, 125.49, 120.78,117.92. MALDI-TOF: m / z calcd for C 20 H 10 BrNO 2[M] + : 376.16; Found: 376.20. The structure is as follows:

[0039] . Example 4

[0040] Synthesis of 7-(4-vinylphenyl)quinolino[3,2,1-de]acridine-5,9-dione (VQA)

[0041] To a 50 mL round-bottom flask containing 7-bromoquinolino[3,2,1-de]acridine-5,9-dione (3) (1.00 g, 2.66 mmol), 4-vinylphenylboronic acid, under an argon atmosphere, using a syringe, Pd(PPh 3 ) 4 (0.15 g, 0.13 mmol), potassium carbonate (0.55 g, 3.99 mmol), toluene (12 mL) and deionized water (2 mL) were mixed. Then, the mixture was heated to 90 °C and refluxed for 24 h. After the mixture was cooled, 20 mL of deionized water was added to the resulting solution, and the mixture was extracted several times with DCM. The organic phase was dried over anhydrous magnesium sulfate. After filtration and evaporation of the solvent, the given residue was purified by silica gel column chromatography using DCM / PE (V / V: 4 / 1) as the eluent to obtain the product (VQA), as a light yellow solid, 1 1H NMR(400 MHz, CDCl 3 ) δ = 8.99 (s,2H), 8.52 (dd, J = 7.9, 1.7 Hz, 2H), 8.16 (d, J= 8.6 Hz, 2H), 7.79 (d, J = 8.3 Hz, 2H), 7.71 (ddd, J= 8.7, 7.0, 1.7 Hz, 2H),7.56 (d, J = 8.3 Hz, 2H), 7.50 (t, J = 7.3 Hz, 2H), 6.79 (dd, J = 17.6,10.9Hz, 1H), 5.87~5.83 (d, 1H), 5.33 (d, J = 11.0 Hz, 1H). 13 13C NMR (101 MHz,CDCl 3) δ = 178.79, 139.86, 138.52, 137.77, 137.62, 136.33, 136.22, 132.93, 130.71, 128.08, 127.35, 127.15, 126.56, 125.41, 124.04, 120.40, 114.72. MALDI-TOF: m / z calcd for C 28 H 17 NO 2 [M] + : 399.10; Found: 398.96. The structure is as follows:

[0042] . Example 5

[0043] Synthesis of P4VQA

[0044] Purify the 4-vinylpyridine solution by vacuum distillation technology to remove the stabilizer. Treat the toluene solution by bubbling experiment operation to obtain ultra-dry toluene. In an argon atmosphere, dissolve 0.01 equivalent (eq) of AIBN and 0.005 equivalent (eq) of VQA in 15 mL of freshly distilled toluene and stir for about 30 min. S4. Add 4-vinylpyridine to the reaction flask and react at 70 °C for 12 h. After the reaction is completed, wait until it cools to room temperature, filter the precipitated solid, then dissolve it in methanol (10 mL), drop the resulting solution into anhydrous ether (300 mL), filter and collect the precipitated polymer to obtain a green powder. The structure is as follows:

[0045] ;

[0046] where m = 1 and n = 0.005.

[0047] Performance characterization of organic super-fluorescent scintillators without heavy-atom modification:

[0048] In this example, the molecular structure of the synthesized material is judged by ultraviolet-visible absorption spectroscopy, powder X-ray diffraction, and nuclear magnetic resonance testing; the emission peak of the synthesized material molecule and the absorption peak of the doped guest material are judged by steady-state spectroscopy, and the emission intensity of the synthesized material molecule is judged by ultraviolet excitation spectroscopy. Figure 1 Part (a) in it is the steady-state spectra of P4VQA with m:n = 1:0.001 and m:n = 1:0.01; Figure 2 Part (a) in it is the absorption spectrum of P4VQA in solution state; Figure 2 Part (b) in it is the steady-state spectra of P4VQA excited at wavelengths of 257 nm and 425 nm;Figure 3 (a) The ultraviolet excitation spectrum after physical blending of P4VQA (m:n = 1:0.005) with PS and PSF; Figure 3 (b) The ultraviolet excitation spectra of P4VQA (m:n = 1:0.005) with the mass ratios of 3:1 and 10:1 to each guest material.

[0049] From the above test results, it can be seen that the heavy-atom-free organic superphosphorescent scintillators prepared in the above examples can be applied to the X-ray field.

[0050] Through reasonable molecular design in the above examples, a new type of organic superphosphorescent scintillator material base is obtained. This material utilizes the characteristics of the VQA material having an amine / carbonyl multi-resonant MR chromophore, covalently binds it in 4-vinylpyridine, and serves as a narrow-band emitter to achieve effective energy transfer from 4VP to VQA. At the same time, 4VP can promote intersystem crossing (ISC) through effective n-π * transition and high triplet energy levels to promote the generation of triplet excitons, which helps to support effective energy transfer from the host to the guest to sensitize the triplet excitons of the guest. Aiming at the problem of low luminescence intensity of P4VQA, P4VQA and polystyrene or polysulfone (mass ratio of 10:1) were weighed separately for doping, and chloroform was used for dissolution to make films. Finally, the films made successfully avoided the problem of low luminescence intensity of the single P4VQA material, effectively promoted the energy transfer efficiency, increased the luminescence intensity of the composite material, and provided the possibility for subsequent application in the X-ray field.

[0051] It should be noted that the above content only illustrates the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. For those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements all fall within the protection scope of the claims of the present invention.

Claims

1. An organic superfluorescent scintillator without heavy atom modification, characterized in that: The structure of the organic superfluorescent scintillator is shown in Formula I: Formula I; Among them, m:n=1:0.

005.

2. A method for preparing an organic superfluorescent scintillator without heavy atom modification, characterized in that: The following steps are involved: S1. Under an argon atmosphere, dimethyl 5-bromo-2-iodoisophthalate, diphenylamine, activated copper powder, potassium carbonate, and cuprous iodide are dissolved in o-dichlorobenzene to react to obtain dimethyl 5-bromo-2-diphenylaminopropionate; S2. Under an argon atmosphere, sodium hydroxide and an ethanol aqueous solution are added to dimethyl 5-bromo-2-diphenylaminopropionate to react to obtain 5-bromo-2-(diphenylamino)pentanoic acid; S3. Under an argon atmosphere, N,N-dimethylformamide is added to a mixture of 5-bromo-2-(diphenylamino)pentanoic acid and dichloromethane, and then oxalyl chloride and tin chloride are added to react to obtain 7-bromoquino[3,2,1-de]acridine-5,9-dione; S4, under an argon atmosphere, dissolving 7-bromoquinolino[3,2,1-de]acridine-5,9-dione, potassium carbonate, tetrakis(triphenylphosphine)palladium, and 4-vinylphenylboronic acid in toluene, adding deionized water, and reacting to obtain 7-(4-vinylphenyl)quinolino[3,2,1-de]acridine-5,9-dione; S5, under an argon atmosphere, adding 7-(4-vinylphenyl)quinoline[3,2,1-de]acridine-5,9-dione, 4-vinylpyridine, and azobisisobutyronitrile to toluene to react and obtain an organic superfluorescent scintillator P4VQA powder product; In step S5, the molar ratio of 4-vinylpyridine to 7-(4-vinylphenyl)quinolino[3,2,1-de]acridine-5,9-dione is 1:0.005; the molar ratio of 4-vinylpyridine to azobisisobutyronitrile is 1:0.01-0.015; and the molar ratio of 4-vinylpyridine to toluene is 1:2; In step S5, the reaction temperature is 65-70°C and the reaction time is 10-12 h; The structure of the organic superfluorescent scintillator P4VQA powder product is shown in Formula I: Formula I, wherein m:n=1:0.

005.

3. The method for preparing an organic superfluorescent scintillator without heavy atom modification according to claim 2, characterized in that: In step S1, the molar ratio of 5-bromo-2-iodoisophthalic acid dimethyl ester, diphenylamine, activated copper powder, potassium carbonate, and cuprous iodide is 1:1.1-1.2:0.15-0.2:1.3-1.4:0.04-0.05; the molar ratio of 5-bromo-2-iodoisophthalic acid dimethyl ester to o-dichlorobenzene is 1:157-158, the reaction temperature is 175-180°C, and the reaction time is 20-24 h.

4. The method for preparing an organic superfluorescent scintillator without heavy atom modification according to claim 2, characterized in that: In step S2, the molar ratio of 5-bromo-2-(diphenylamino)pentanoic acid dimethyl ester to sodium hydroxide is 1:5; the volume ratio of ethanol to water in the ethanol aqueous solution is 1:1, and the molar ratio of 5-bromo-2-(diphenylamino)pentanoic acid dimethyl ester to ethanol is 1:53-54; the reaction temperature is 75-80°C, and the reaction time is 20-24 h.

5. The method for preparing an organic superfluorescent scintillator without heavy atom modification according to claim 2, characterized in that: In step S3, the molar ratio of 5-bromo-2-(diphenylamino)pentanoic acid to oxalyl chloride is 1:2.1-2.2; the molar ratio of 5-bromo-2-(diphenylamino)pentanoic acid to tin chloride is 1:2.1-2.2; the volume ratio of N,N-dimethylformamide to dichloromethane is 1.5:80; the molar ratio of 5-bromo-2-(diphenylamino)pentanoic acid to dichloromethane is 1:500-520.

6. The method for preparing an organic superfluorescent scintillator without heavy atom modification according to claim 2, characterized in that: Step S3 also includes the following steps: in an ice-water bath, N,N-dimethylformamide is added to a mixture of 5-bromo-2-(diphenylamino)pentanoic acid and dichloromethane, and then oxalyl chloride is added dropwise, the ice-water bath is removed, and the mixture is reacted at a temperature of 40-45° C. for 30 min, and then tin chloride is added dropwise and the same temperature is maintained to continue condensing and reflux for 3 h.

7. The method for preparing an organic superfluorescent scintillator without heavy atom modification according to claim 2, characterized in that: In step S4, the molar ratio of 7-bromoquinoline [3,2,1-de] acridine-5,9-dione to 4-vinylbenzene boronic acid is 1:1.4-1.5, the molar ratio of 7-bromoquinoline [3,2,1-de] acridine-5,9-dione to potassium carbonate is 1:1.4-1.5; the molar ratio of potassium carbonate to tetrakis (triphenylphosphine) palladium is 1:0.032-0.033; the molar ratio of 7-bromoquinoline [3,2,1-de] acridine-5,9-dione to toluene is 1:42-45; the volume ratio of toluene to deionized water is 2:1; the reaction temperature is 85-90°C, and the reaction time is 20-24 h.

8. Use of the organic superfluorescent scintillator without heavy atom modification as claimed in claim 1 in the field of X-rays.

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