CN109942578B - Organic compounds of heteroanthracene class, preparation method and application - Google Patents

Abstract

The invention relates to the technical field of semiconductors, in particular to a heteroanthracene organic compound and a preparation method and application thereof. The structural formula of the heteroanthracene organic compound is shown in chemical formula 1:

Description

Xanthene organic compound and preparation method and application thereof

technical field

The invention relates to the technical field of semiconductors, in particular to a xanthene organic compound and a preparation method and application thereof.

Background technique

Organic electroluminescence (OLED: Organic Light Emission Diodes) device technology can be used to manufacture new display products and new lighting products. The OLED light-emitting device includes electrode materials and organic functional materials sandwiched between different electrodes. Various functional materials are superimposed on each other according to the application to form an OLED light-emitting device. When a voltage is applied to the electrodes at both ends, and the positive and negative charges in the organic functional material layer are acted upon by an electric field, the positive and negative charges are further combined in the light-emitting layer, that is, OLED electroluminescence is generated.

The OLED photoelectric functional material film layer constituting the OLED device includes at least two or more layers of structure, and the industrially applied OLED device structure includes a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, and an electron transport layer. Layer, electron injection layer and other film layers, that is to say, the optoelectronic functional materials applied to OLED devices include at least hole injection materials, hole transport materials, light-emitting materials, electron transport materials, etc., and the material types and matching forms are rich. and diversity characteristics. In addition, for the collocation of OLED devices with different structures, the optoelectronic functional materials used have strong selectivity, and the performance of the same material in devices with different structures may also be completely different. Therefore, it is very important to develop functional materials with new structures.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a novel xanthene organic compound and its preparation method and application. The compound of the present invention has high glass transition temperature and molecular thermal stability, and can effectively improve the photoelectricity of OLED devices by optimizing the device structure. performance and device lifetime.

In order to achieve the above object, the technical scheme of the present invention is as follows:

A xanthene organic compound, the structural formula of which is shown in Chemical Formula 1:

in:

R ₁ and R ₂ each independently represent a substituted or unsubstituted C1-C60 alkyl group, a C3-C60 cycloalkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a C3-C60 cycloalkenyl group, substituted or unsubstituted C3-C60 alkynyl group, C3-C60 cycloalkynyl group, substituted or unsubstituted C6-C60 aryl group or C6-C60 heterocyclic group;

_R3 and _R4 each independently represent: hydrogen, isotopes of hydrogen, halogen, cyano, nitro, hydroxyl, amino, sulfonic acid, sulfonyl, phosphoric acid, phosphoryl, substituted or unsubstituted silicon, boron Alkyl, phosphorus, substituted or unsubstituted C1-C60 alkyl, C3-C60 cycloalkyl, alkoxy, alkylamino, alkylmercapto, substituted or unsubstituted C2-C60 alkenyl, C3 ~C60 cycloalkenyl, substituted or unsubstituted C3~C60 alkynyl, C3~C60 cycloalkynyl, substituted or unsubstituted C6~C60 aryl or C6~C60 heterocyclic group; or adjacent to The substituents are connected to form a substituted or unsubstituted monocyclic or polycyclic C3-C30 alicyclic or aromatic ring, the carbon atom of which can be replaced by at least one heteroatom selected from nitrogen, oxygen or sulfur;

m and n are integers from 0 to 4;

Ar ₁ is a substituted or unsubstituted C5-C30 aromatic ring or a substituted or unsubstituted C5-C60 heterocycle;

Ar ₂ is a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C1-C30 heteroaryl group; or is connected with an adjacent substituent to form a single ring or A polycyclic C3-C30 alicyclic or aromatic ring, the carbon atom of which may be replaced by at least one heteroatom selected from nitrogen, oxygen or sulfur.

In the above technical solution, preferably Ar ₁ is a benzene ring, a naphthalene ring, an anthracene ring, a pyrene ring or a phenanthrene ring.

In the above technical scheme, preferably Ar ₂ is phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, pyrenyl, furyl, thienyl, pyridyl, pyrimidinyl, pyridazinyl, One of pyrazinyl, triazinyl, quinazoline, benzimidazole, acridine and its derivatives, oxazole, thiazole, phenothiazine, isopropyl and cyclohexyl.

In the above-mentioned technical scheme, it is further preferred that Ar ₂ is any one selected from the following structures:

Wherein: R is hydrogen, halogen, cyano, C1-C30 alkyl, C6-C50 aryl, C7-C50 aralkyl, C7-C50 arylalkoxy, C7-C50 arylalkoxy A mercapto group or a C5-C50 heteroaryl group; and the -R represents any position on the benzene ring where it is located, and "*" is a connecting position.

In the above technical scheme, the xanthene organic compound is selected from any one of the following structures:

A preparation method of xanthene organic compound, comprising the following steps:

1. Synthesis of intermediate C: under nitrogen atmosphere, add raw material B and NaOt-Bu into dry toluene and stir for 20min, then add raw material A, Pd(OAc) ₂ and P(t-Bu) ₃ , and react after heating up; After monitoring the reaction, it was cooled to room temperature, washed with water, layered, extracted, and separated by silica gel column chromatography to obtain Intermediate C; the preferred reaction temperature was 80°C, and the reaction time was 6h;

2. the synthesis of intermediate E: the intermediate C is dissolved in anhydrous tetrahydrofuran, cooled to about 0 ℃, the Grignard reagent D is added dropwise, and then the temperature is raised to carry out the reaction; Extraction with ethyl acetate, the obtained organic phase is washed with saturated aqueous sodium bicarbonate solution, dried and separated by silica gel column chromatography to obtain intermediate E; the preferred reaction temperature is 40°C, and the reaction time is 6h;

When the raw material B contains the R ₁ group, the Grignard reagent D is R ₂ MgBr; when the raw material B contains the R ₂ group, the Grignard reagent D is R ₁ MgBr;

3. Synthesis of Intermediate F: Intermediate E is dissolved in dry tetrahydrofuran and toluene mixed solvent, and methanesulfonic acid is added at room temperature to carry out the reaction; phase, washed with saturated aqueous sodium bicarbonate solution, and dried to remove the organic solvent to obtain intermediate F; the preferred reaction time is 8h;

④ Synthesis of intermediate H: Under nitrogen atmosphere, intermediate F and NaOt-Bu were added to dry toluene and stirred for 20 min, then intermediate G, Pd(OAc) ₂ and P(t-Bu) ₃ were added, and the reaction was carried out after heating up. ; After monitoring the reaction, it was cooled to room temperature, washed with water, layered, extracted, and separated by silica gel column chromatography to obtain intermediate H; the preferred reaction temperature was 80°C, and the reaction time was 6h;

5. Synthesis of intermediate I: intermediate H is added to triethyl phosphite, and the reaction is heated and reacted; after the reaction is completed, it is cooled to room temperature, and the reaction solution is slowly added to the ice water, and a large amount of solid is obtained to separate out, stir 1h, filter, add dichloromethane to the solid, stir the solid to dissolve basically, add petroleum ether to have a solid precipitate, stir for 1h, filter and dry to obtain Intermediate I; the preferred reaction temperature is 155 ° C, and the reaction time is 5 hours;

⑥ Synthesis of the final product shown in chemical formula 1: under nitrogen atmosphere, intermediate I and NaOt-Bu were added to dry toluene and stirred for 20 min, followed by intermediate J, Pd(OAc) ₂ and P(t-Bu) ₃ , The reaction is carried out after heating up; after the monitoring reaction is completed, it is cooled to room temperature, washed with water, layered, extracted, and separated by a silica gel column to obtain the final product shown in chemical formula 1; the preferred reaction temperature is 80°C, and the reaction time is 6h;

Its synthetic route is as follows:

wherein: R ₁ , R ₂ , R ₃ , R ₄ , Ar ₁ , Ar ₂ , m and n are consistent with the ranges defined in Chemical Formula 1, and X is halogen.

The present invention also provides an application of the xanthene organic compound for preparing an organic electroluminescence device. The organic electroluminescent device includes at least one functional layer containing the organic compound represented by Chemical Formula 1.

The present invention also provides an organic electroluminescence device, comprising an electron blocking layer, and the material of the electron blocking layer is the organic compound represented by the chemical formula 1.

The present invention also provides an organic electroluminescence device, comprising a light-emitting layer, wherein the light-emitting layer contains the organic compound represented by the chemical formula 1.

The beneficial effects of the present invention are:

The xanthene organic compound provided by the present invention can be applied to the fabrication of OLED light-emitting devices, and compared with the device in Comparative Example 1, both the efficiency and the lifespan are greatly improved compared with the known OLED materials, especially the lifespan of the device Attenuation gets a big boost.

The preparation method of the xanthene organic compound provided by the invention is simple and feasible, has high yield, and is suitable for industrial production.

Detailed ways

Example 1: Synthesis of Compound 1

Under nitrogen atmosphere, 2-aminobenzophenone (19.7 g, 100 mmol) and NaOt-Bu (19.2 g, 200 mmol) were added to 200 mL of dry toluene and stirred for 20 min, followed by bromobenzene (15.6 g, 100 mmol), Pd ( OAc) ₂ (0.2 g, 1 mmol) and P(t-Bu) ₃ (0.8 g, 2 mmol) were heated to 80 °C and reacted for 6 h. After monitoring the reaction, it was cooled to room temperature, washed with 300 mL of water, separated into layers, extracted, and separated by silica gel column chromatography to obtain compound C-124.58 g with a yield of 90%.

Intermediate C-1 (24.58 g, 90 mmol) was dissolved in 300 mL of anhydrous tetrahydrofuran, cooled to about 0 °C, phenylmagnesium bromide solution (44 mL, 110 mmol) was added dropwise, and then the temperature was raised to 40 °C for 6 h. After the reaction was completed, it was cooled to room temperature, washed with 300 mL of water, layered, extracted with 300 mL of ethyl acetate, the obtained organic phase was washed with saturated aqueous sodium bicarbonate solution, dried and separated on a silica gel column to obtain intermediate E-125.28 g, which was collected rate 80%.

Intermediate E-1 (25.28 g, 72 mmol) was dissolved in a dry mixed solvent of 150 mL of tetrahydrofuran and 150 mL of toluene, methanesulfonic acid (34.56 g, 360 mmol) was added at room temperature, and the reaction was carried out for 8 h. After the reaction, 300 mL of water and ethyl acetate were added to stir, the layers were separated, the organic phase was collected, washed with saturated aqueous sodium bicarbonate solution, dried and removed the organic solvent to obtain intermediate F-122.79g, yield 95%.

Under nitrogen atmosphere, intermediate F-1 (22.79 g, 72 mmol) and NaOt-Bu (13.8 g, 144 mmol) were added to 200 mL of dry toluene and stirred for 20 min, followed by intermediate G-1 (14.47 g, 72 mmol), Pd (OAc) ₂ (0.14 g, 0.72 mmol) and P(t-Bu) ₃ (0.58 g, 1.44 mmol) were heated to 80° C. and reacted for 6 h. After monitoring the reaction, it was cooled to room temperature, washed with 300 mL of water, layered, extracted, and separated by silica gel column chromatography to obtain intermediate H-127.8 g with a yield of 85%.

Intermediate H-1 (27.8 g 61.2 mmol) was added to 140 mL of triethyl phosphite and the reaction was heated to 155°C for 5 hours. After the reaction was completed, it was cooled to room temperature. The reaction solution was slowly added to 1L of ice water, a large amount of solid was precipitated, stirred for 1h, filtered, 100mL of dichloromethane was added to the solid, the solid was basically dissolved by stirring, and 500mL of petroleum ether was added to precipitate solid, stirred for 1h, filtered and dried. The intermediate I-119.38 g was obtained with a yield of 75%.

Under nitrogen atmosphere, intermediate I-1 (19.38 g, 45.9 mmol) and NaOt-Bu (8.8 g, 91.8 mmol) were added to 200 mL of dry toluene and stirred for 20 min, followed by bromobenzene (7.16 g, 45.9 mmol), Pd (OAc) ₂ (0.092 g, 0.46 mmol) and P(t-Bu) ₃ (0.368 g, 0.92 mmol) were heated to 80° C. and reacted for 6 h. After monitoring the reaction, it was cooled to room temperature, washed with 300 mL of water, separated into layers, extracted, and separated by silica gel column chromatography to obtain compound 118.75 g with a yield of 82%. ESI-MS (m/z) (M+): theoretical value 498.21, found value 498.34.

Example 2: Synthesis of Compound 2

Compound 2 was prepared according to the method of Compound 1 in Example 1. The difference is that the intermediate J-1 in Example 1 is replaced by the intermediate J-2 (tetrabromobiphenyl), and the rest are the same to obtain compound 2 with a yield of 78%. ESI-MS (m/z) (M+): theoretical value 574.24, found value 574.54.

Example 3: Synthesis of Compound 10

Compound 10 was prepared according to the method of Compound 1 in Example 1. The difference is that the intermediate J-1 in Example 1 is replaced by the intermediate J-10 (3-bromo-9 phenylcarbazole), and the rest are the same to obtain compound 10 with a yield of 80%. ESI-MS (m/z) (M+): Theoretical value is 663.27, and the found value is 663.74.

Example 4: Synthesis of Compound 14

Compound 14 was prepared according to the method of Compound 1 in Example 1. The difference is that the raw material B-1 in Example 1 is replaced with the raw material B-14, and the Grignard reagent D-1 is replaced with D-14, and the rest are the same to obtain compound 14 with a yield of 75%. ESI-MS (m/z) (M+): Theoretical value is 506.24, and the found value is 506.34.

Example 5: Synthesis of Compound 18

Compound 18 was prepared according to the method of Compound 1 in Example 1. The difference is that the intermediate J-1 in Example 1 is replaced by the intermediate J-18, and the rest are the same. Compound 18 was obtained in 83% yield ESI-MS (m/z) (M+): theoretical value 690.28, found value 690.24.

Example 6: Synthesis of Compound 32

Compound 32 was prepared according to the method of Compound 1 in Example 1. The difference is that the raw material B-1 in Example 1 is replaced by B-32, and J-1 is replaced by the intermediate J-32, and the rest are the same to obtain compound 32 with a yield of 76%. ESI-MS(m/z)(M+): Theoretical value is 672.26, and the found value is 672.28.

Example 7: Synthesis of Compound 49

Compound 49 was prepared following the procedure for compound 32 in Example 6. The difference is that the intermediate J-32 in Example 6 was replaced by J-49, and the rest were the same to obtain compound 49 with a yield of 79%. ESI-MS (m/z) (M+): Theoretical value is 638.24, and the found value is 638.58.

Example 8: Synthesis of Compound 54

Compound 54 was prepared as in Example 6 for compound 32. The difference is that the intermediate J-32 in Example 6 was replaced with J-54, and the rest were the same to obtain compound 54 with a yield of 81%. ESI-MS (m/z) (M+): Theoretical value is 625.25, and the found value is 625.36.

Example 9: Synthesis of Compound 70

Compound 70 was prepared as in Example 6 for compound 32. The difference is that the intermediate J-32 in Example 6 is replaced by J-70, and the rest are the same. The yield of compound 70 was 79% ESI-MS (m/z) (M+): the theoretical value was 740.29, and the found value was 740.86.

Example 10: Synthesis of Compound 72

Compound 72 was prepared as in Example 6 for compound 32. The difference is that the intermediate J-32 in Example 6 was replaced with J-72, and the rest were the same to obtain compound 72 with a yield of 84%. ESI-MS (m/z) (M+): theoretical value 755.33, found value 755.36.

Example 11: Synthesis of Compound 84

Compound 84 was prepared according to the method of Compound 1 in Example 1. The difference is that the raw material B-1 in Example 1 is replaced by B-84, and J-1 is replaced by the intermediate J-84, and the rest are the same to obtain compound 84 with a yield of 74%. ESI-MS (m/z) (M+): theoretical value 878.34, found value 878.18.

Example 12: Synthesis of Compound 90

Compound 90 was prepared according to the method of Compound 1 in Example 1. The difference is that the raw material B-1 in Example 1 is replaced with B-90, the Grignard reagent D-1 is replaced with the raw material D-84, and the rest are the same to obtain compound 90 with a yield of 84%. ESI-MS(m/z)(M+): Theoretical value is 664.29, and the found value is 664.78.

Example 13: Synthesis of Compound 92

Compound 92 was prepared according to the method of Compound 1 in Example 1. The difference is that the raw material B-1 in Example 1 is replaced with B-92, the intermediate G-1 is replaced with the raw material G-92, and the intermediate J-1 is replaced with J-92, and the rest are the same. The yield of compound 92 was 81% ESI-MS (m/z) (M+): the theoretical value was 748.29, the found value was 748.79.

The thermal decomposition temperature (Td) of the compounds synthesized in Examples 1 to 13 and the known host compound CBP was measured by thermogravimetric analysis. The glass transition temperatures (Tg) of the above compounds were measured using differential scanning calorimetry. The results are shown in Table 1:

Table 1

compound Td(℃) Tg(℃) 1 433 142 2 421 145 10 419 150 14 427 146 18 419 151 32 426 147 49 440 144 54 438 152 70 427 148 72 435 146 84 426 141 90 417 150 92 426 143 CBP 342 98

Device Embodiment 1: An electroluminescent device, the preparation steps of which include:

The ITO anode layer on the transparent substrate layer was cleaned, and ultrasonically cleaned with deionized water, acetone, and ethanol for 15 minutes respectively, and then treated in a plasma cleaner for 2 minutes; b) on the ITO anode layer, evaporated by vacuum evaporation The hole injection layer material HAT-CN is plated with a thickness of 10 nm, and this layer is used as the hole injection layer; c) On the hole injection layer, the hole transport material NPB is evaporated by vacuum evaporation with a thickness of 60 nm. is a hole transport layer; d) a light-emitting layer is vapor-deposited on the hole transport layer, using Compound 1 in Example 1 as a host material, Ir(ppy) ₃ as a dopant material, Ir(ppy) ₃ and Compound 1 The mass ratio is 5:9:5, and the thickness is 30nm; f) On the light-emitting layer, the electron transport material TPBI is evaporated by vacuum evaporation with a thickness of 40nm; g) On the electron transport layer, vacuum evaporation Electron injection layer LiF with a thickness of 1nm, this layer is an electron injection layer; h) on top of the electron injection layer, vacuum evaporation of cathode Al (100nm), this layer is a cathode reflective electrode layer, to make the electroluminescent device .

Device Example 2: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is Compound 2 of the present invention.

Device Example 3: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is compound 10 of the present invention.

Device Example 4: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 14 of the present invention.

Device Example 5: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 18 of the present invention.

Device Example 6: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 32 of the present invention.

Device Example 7: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is compound 49 of the present invention.

Device Example 8: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 54 of the present invention.

Device Example 9: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 70 of the present invention.

Device Example 10: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 72 of the present invention.

Device Example 11: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is the compound 84 of the present invention.

Device Example 12: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is compound 90 of the present invention.

Device Example 13: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is compound 92 of the present invention.

Device Comparative Example 1: The difference between this example and Device Example 1 is that the host material of the light-emitting layer of the electroluminescent device is CBP.

The electroluminescence properties of the fabricated OLEDs are shown in Table 2.

Table 2

compound Current efficiency color LT95 life Example 1 1 1.8 green 9.2 Example 2 2 2.0 green 9.1 Example 3 10 1.9 green 9.0 Example 4 14 2.3 green 9.4 Example 5 18 2.1 green 9.5 Example 6 32 2.5 green 9.4 Example 7 49 2.4 green 9.7 Example 8 54 1.9 green 9.5 Example 9 70 2.1 green 9.9 Example 10 72 2.4 green 9.7 Example 11 84 2.6 green 9.2 Example 12 90 2.4 green 9.1 Example 13 92 2.2 green 9.0 Comparative Example 1 CBP 1.0 green 1.0

The device test performance is based on Comparative Example 1, and each performance index of the device in Comparative Example 1 is set to 1.0. The current efficiency of Comparative Example 1 is 28cd/A (@10mA/cm ² ); the lifetime decay of LT95 is 2.5Hr at 5000 brightness.

From the results in the table, it can be seen that the organic compounds described in the present invention can be applied to the fabrication of OLED light-emitting devices, and compared with the device Comparative Example 1, both the efficiency and the lifespan are greatly improved compared with the known OLED materials, especially It is the life attenuation of the device that has been greatly improved.

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. And the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (6)

1. a xanthene organic compound, is characterized in that, it is selected from any one in following structure:

2. a preparation method of xanthene organic compound according to claim 1, is characterized in that, comprises the following steps: ①Synthesis of intermediate C: under nitrogen atmosphere, add raw material B and NaOt-Bu into toluene and stir, then add raw material A, Pd(OAc) ₂ and P(t-Bu) ₃ , and then react after heating up; monitor the reaction After finishing, it was cooled to room temperature, washed with water, layered, extracted, and separated by silica gel column to obtain Intermediate C; ②Synthesis of intermediate E: Dissolve intermediate C in anhydrous tetrahydrofuran, add Grignard reagent DR ₂ MgBr or R ₁ MgBr dropwise, and then heat up to react; Use ethyl acetate to extract, the obtained organic phase is washed with saturated aqueous sodium bicarbonate solution, and after drying, the silica gel column is separated to obtain intermediate E; 3. the synthesis of intermediate F: the intermediate E is dissolved in a mixed solvent of tetrahydrofuran and toluene, and methanesulfonic acid is added at normal temperature to carry out the reaction; after the reaction is completed, water and ethyl acetate are added to stir respectively, and the layers are separated, and the organic phase is collected, Wash with saturated aqueous sodium bicarbonate solution, and remove the organic solvent after drying to obtain Intermediate F; ④ Synthesis of intermediate H: under nitrogen atmosphere, intermediate F and NaOt-Bu were added to toluene and stirred, then intermediate G, Pd(OAc) ₂ and P(t-Bu) ₃ were added, and the reaction was carried out after heating up; monitoring After the reaction is completed, it is cooled to room temperature, washed with water, layered, extracted, and separated by a silica gel column to obtain intermediate H; 5. Synthesis of intermediate I: intermediate H is added to P(OEt) ₃ , and the reaction is heated and reacted; the reaction is completed, cooled to room temperature, the reaction solution is added to the ice water, and a large amount of solid is precipitated, and stirring, Filter, add methylene chloride to the solid, stir the solid to dissolve, add petroleum ether to have the solid to separate out, stir, filter, and dry to obtain Intermediate I; ⑥ Synthesis of the final product shown in chemical formula 1: under nitrogen atmosphere, intermediate I and NaOt-Bu were added to dry toluene and stirred, then intermediate J, Pd(OAc) ₂ and P(t-Bu) ₃ were added, and the temperature was increased. After the reaction is monitored, the reaction is cooled to room temperature, washed with water, layered, extracted, and separated by a silica gel column to obtain the final product shown in Chemical Formula 1; Its synthetic route is as follows:

Wherein, X is halogen; R ₁ -R ₄ , m, n, Ar ₁ , Ar ₂ correspond to the substituent groups on each compound in claim 1 . 3 . The application of the xanthene-based organic compound as claimed in claim 1 or prepared by the method as claimed in claim 2 for preparing organic electroluminescence devices. 4 . 4 . The application according to claim 3 , wherein the organic electroluminescence device comprises at least one functional layer containing the xanthene organic compound prepared by the method of claim 1 or claim 2 . 5 . . 5 . The application according to claim 3 , wherein the organic electroluminescence device comprises an electron blocking layer, and the material of the electron blocking layer is prepared by the method described in claim 1 or claim 2 . 6 . of xanthene organic compounds. 6 . The application according to claim 3 , wherein the organic electroluminescence device comprises a light-emitting layer, and the light-emitting layer contains the xanthene prepared by the method of claim 1 or claim 2 . organic compounds.