CN111777614B

CN111777614B - Organic electroluminescent compound and application thereof

Info

Publication number: CN111777614B
Application number: CN202010747182.4A
Authority: CN
Inventors: 陈志宽; 李祥智; 蔡烨; 魏定纬; 丁欢达
Original assignee: Ningbo Dinghao Photoelectric Material Technology Co ltd; Ningbo Research Institute of Northwestern Polytechnical University; Ningbo Lumilan Advanced Materials Co Ltd
Current assignee: Ningbo Dinghao Photoelectric Material Technology Co ltd; Ningbo Research Institute of Northwestern Polytechnical University; Ningbo Lumilan Advanced Materials Co Ltd
Priority date: 2020-07-29
Filing date: 2020-07-29
Publication date: 2023-04-07
Anticipated expiration: 2040-07-29
Also published as: CN111777614A

Abstract

The invention relates to an organic electroluminescent compound and application thereof, wherein the organic electroluminescent compound has a structure shown in a formula I. The invention provides a novel organic electroluminescent compound, which takes a special condensed ring structure as a mother core, the structure has a certain angle of torsion, the hole transmission rate is reduced to a certain extent, the hole and electron transmission rate balance is facilitated, and when the novel organic electroluminescent compound is applied to an organic electroluminescent device, particularly when the novel organic electroluminescent compound is used as a main body material of a light-emitting layer, the device can have higher luminous efficiency, lower driving voltage and longer service life.

Description

Organic electroluminescent compound and application thereof

Technical Field

The invention relates to the technical field of organic electroluminescence, in particular to an organic electroluminescent compound and application thereof.

Background

In 1987, dune green cloud doctor, et al, a laboratory of Kodak corporation of america (Eastman Kodak), first made a first organic light-emitting diode (OLED) device (hereinafter referred to as OLED device) by vacuum evaporation (appl. Phys. Lett.,1987,51, 913), which uses transparent and conductive Indium Tin Oxide (ITO) as a cathode, and on which a diamine derivative and tris (8-hydroxyquinoline) aluminum are sequentially evaporated, and a magnesium-silver alloy is used as an anode material, and such a multilayer structure can reduce the driving voltage of the OLED device, and effectively improve the charge injection problem between the material molecules and the electrode interface, and thus the device performance and lifetime are improved.

Compared with the traditional light-emitting technology, the OLED device has the advantages of low driving voltage, high light-emitting efficiency, high contrast, high color saturation, wide visual angle, quick response time and the like, has great potential to replace a mainstream liquid crystal display, and becomes a star technology in the display field. The increasing demand in the display field also drives the rapid development of OLED device structures and organic photoelectric materials, which are embodied as compounds and materials with new structures, functional groups and substituents, and simultaneously, the OLED device structures are continuously optimized and gradually developed from the initial sandwich structure into complex structures composed of multiple functional layers. The current OLED device comprises a plurality of layers of a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer, and suitable electrodes, and these layers are respectively composed of the following materials: hole injection materials, hole transport materials, light emitting materials, hole blocking materials, electron transport materials, and electron injection materials. The OLED light-emitting layer manufactured in a doping mode has advantages in the light-emitting efficiency of the device, so that the light-emitting layer material is usually formed by doping a host material with a guest material, and the host material is an important factor influencing the light-emitting efficiency and performance of the OLED device.

At present, the number of the current day,

the CBP is a widely applied main body material and has good hole transport property, but when the CBP is used as the main body material, the CBP is easy to recrystallize due to low glass transition temperature, so that the service performance and the luminous efficiency of an OLED device are reduced. On the other hand, CBP is a hole-type host material, the transport of electrons and holes is unbalanced, the recombination efficiency of excitons is low, the light emitting region is not ideal, and the roll-off phenomenon is severe during the operation of the device, which results in low efficiency of energy transfer from the host material to the guest material and reduces the efficiency of the device.

Therefore, it is a technical problem in the art to improve the thermal stability and energy transfer efficiency of the host material, thereby further optimizing the light emitting efficiency and driving voltage of the organic electroluminescent device.

Disclosure of Invention

An object of the present invention is to provide an organic electroluminescent compound, and more particularly, to provide a host material of a light-emitting layer, which has high thermal stability and energy transfer efficiency, and has high light-emitting efficiency, low driving voltage and long service life when applied to an organic electroluminescent device.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides an organic electroluminescent compound, which has a structure shown in a formula I;

in the formula I, the Y ¹ And Y ² Each independently selected from N-L-Ar, O, S or CR _a R _b Said R is _a And R _b Are not connected or connected through a single bond;

ar is selected from substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C3-C60 heteroaryl or

Any one of the above; the bond at the wavy line mark represents a group;

ar is ¹ And Ar ² Each independently selected from any one of substituted or unsubstituted C6-C60 aryl and substituted or unsubstituted C3-C60 heteroaryl;

said R is _a And R _b Each independently selected from any one of hydrogen, deuterium, tritium, cyano, nitro, halogen, substituted or unsubstituted C1-C30 straight-chain alkyl, substituted or unsubstituted C3-C30 branched-chain alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C60 aryl, and substituted or unsubstituted C3-C60 heteroaryl;

in the formula I, R is ¹ 、R ² 、R ³ 、R ⁴ And R ⁵ Each independently selected from hydrogen, deuterium, tritium, cyano, nitro, halogen, substituted or unsubstituted C1-C30 straight chain alkyl, substituted or unsubstituted C3-C30 branched chain alkyl substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C2-C30 alkoxy, or a pharmaceutically acceptable salt thereof substituted or unsubstituted C1-C30 thioalkoxy, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C6-C60 aryloxy, substituted or unsubstituted C6-C60 thioaryloxy, substituted or unsubstituted C3-C60 heteroaryl, substituted or unsubstituted C3-C60 heteroaryloxy, substituted or unsubstituted C3-C60 thioheteroaryloxy, substituted or unsubstituted C6-C60 thioaryloxy, substituted or unsubstituted C6-C60 heteroaryloxy, or substituted or unsubstituted C6-C60 heteroaryloxy,

Or at least two of them are linked, or R is ¹ 、R ² 、R ³ 、R ⁴ And R ⁵ Wherein adjacent groups on the same phenyl ring are linked to form a substituted or unsubstituted C6-C60 aromatic ring or a substituted or unsubstituted C3-C60 heteroaromatic ring; the "C6-C30 aromatic ring" and the "C3-C30 heteroaromatic ring" are linked to the benzene ring on the parent nucleus in formula I in such a way that they share two carbon atoms, i.e. to the parent nucleus(ii) fused; the "adjacent groups" refer to two groups adjacent to each other on the same benzene ring, for example, when two adjacent R's are substituted on the benzene ring ⁵ Two of these R ⁵ May be linked to form a substituted or unsubstituted C6-C30 aromatic ring or a substituted or unsubstituted C3-C30 heteroaromatic ring;

the R is ⁶ 、R ⁷ 、R ⁸ 、R ⁹ And R ¹⁰ Each independently selected from any one or at least two of hydrogen, deuterium, tritium, cyano, nitro, halogen, substituted or unsubstituted C1-C30 straight-chain alkyl, substituted or unsubstituted C3-C30 branched-chain alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C6-C60 aryl and substituted or unsubstituted C3-C60 heteroaryl;

l, L ¹ And L ² Each independently selected from a single bond or a substituted or unsubstituted C6-C30 aryl or a substituted or unsubstituted C3-C60 heteroaryl, preferably a single bond or phenylene;

in formula I, m and k are each independently an integer from 0 to 3, such as 1 or 2, n, p, q are each independently an integer from 0 to 4, such as 1,2 or 3;

Ar、Ar ¹ 、Ar ² 、R ¹ -R ¹⁰ 、R _a 、R _b 、L、L ¹ and L ² Wherein each of the substituted groups is independently selected from at least one or a combination of two of deuterium, tritium, halogen, cyano, C1-C20 linear alkyl, deuterium substituted C1-C20 linear alkyl, halogen substituted C1-C20 linear alkyl, C3-C20 branched alkyl, deuterium substituted C3-C20 branched alkyl, halogen substituted C3-C20 branched alkyl, C3-C20 cycloalkyl, deuterium substituted C3-C20 cycloalkyl, halogen substituted C3-C20 cycloalkyl, C6-C30 aryl, deuterium substituted C6-C30 aryl, halogen substituted C6-C30 aryl, cyano substituted C6-C30 aryl, C3-C30 heteroaryl, deuterium substituted C3-C30 heteroaryl, halogen substituted C3-C30 heteroaryl, cyano substituted C3-C30 heteroaryl, C1-C20 alkoxy, C2-C20 alkenyl, C6-C30 aryloxy, C6-C30 arylamino, C3-C30 heteroarylamino, and C3-C30 heteroarylamino. The substituted group may be selected fromAny one or at least two of the above groups may be selected from the above groups bonded by chemical bond.

In the present invention, the wavy line marks all represent the bonds of the groups.

In the present invention, the expression that a single bond crosses a ring means that a group can be attached at any attachable site of the ring.

In the present invention, halogen includes, but is not limited to, fluorine, chlorine, bromine, iodine, and the like.

The invention provides a novel organic electroluminescent compound with a special condensed ring structure

The structure is a mother core, the structure has torsion at a certain angle, the hole transmission rate is reduced to a certain extent, the hole and electron transmission rate balance is facilitated, and when the structure is applied to an organic electroluminescent device, particularly when the structure is used as a main body material of a light-emitting layer, the device can have high luminous efficiency, low driving voltage and long service life.

Preferably, in formula I, Y is ¹ And Y ² At least one of them is N-L-Ar.

Preferably, in formula I, R ¹ 、R ² 、R ³ 、R ⁴ And R ⁵ Are all hydrogen.

Preferably, in formula I, R is _a And R _b Each independently selected from C1-C10 alkyl or C6-C30 aryl, preferably methyl or phenyl.

Preferably, the organic electroluminescent compound has a structure shown in formula II or formula III;

said X ¹ And X ² Each independently a single bond, N-L-Ar, O, S or C (L-Ar) ₂ Any one of the above;

r and s are each independently an integer of 0 to 4, e.g., 1,2, or 3, etc.;

r 'and R' are independently selected from any one or at least two of hydrogen, deuterium, tritium, cyano, nitro, halogen, C1-C10 straight-chain alkyl, C3-C10 branched-chain alkyl, C3-C10 cycloalkyl, C2-C10 alkenyl, C1-C10 alkoxy, C6-C30 aryl, C3-C30 heteroaryl, C6-C30 arylamino, C3-C30 heteroarylamino and C3-C30 arylheteroarylamino;

ar, L ¹ 、L ² 、Y ¹ 、Y ² 、R ¹ -R ⁴ M, n, p and q all have the same selection ranges as before.

Preferably, in formula II, R ¹ -R ⁴ And R' are both hydrogen.

Preferably, in formula III, R ¹ -R ⁴ And R "are both hydrogen.

Preferably, in formula II, X is ¹ And X ² At least one of which is a single bond, preferably, only one of which is a single bond.

Preferably, in formula II, Y is ¹ 、Y ² 、X ¹ And X ² At least one of them is N-L-Ar, preferably one or two of them are N-L-Ar, and more preferably two of them are N-L-Ar.

Preferably, in formula III, said Y ¹ And Y ² At least one of them is N-L-Ar, preferably one or two of them are N-L-Ar, and more preferably two of them are N-L-Ar.

The preferred compound contains N-L-Ar groups, the N-L-Ar groups are matched with the mother nucleus and can promote carrier transmission, so that the luminous efficiency of the device is further improved, the driving voltage is reduced, the service life is prolonged, the number of N-L-Ar is preferably one or two, and the excessive number of N-L-Ar can cause the imbalance of electron and hole transmission, thereby reducing the current efficiency.

Preferably, the organic electroluminescent compound has any one of the following structures:

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the Ar 'has the same selection range as the Ar, and the L' has the same selection range as the L.

Preferably, the Ar has any one of the following structures:

z is ¹ -Z ²² Each independently selected from N or CR ¹¹ ；

The R is ¹¹ Each independently selected from hydrogen, deuterium, tritium, cyano, nitro, halogen, C1-C10 straight chain alkyl, C3-C10 branched alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, C6-C30 aryl, C6-C30 aryloxy, C3-C30 heteroaryl, and mixtures thereof,

Any one or at least two of them are linked to form a group; when substituted with at least two R ¹¹ When these are at least two R ¹¹ May be the same or different;

said L ³ Selected from a single bond or a C6-C30 aryl;

said R is ¹² And R ¹³ Each independently selected from any one of C6-C30 aryl and C3-C30 heteroaryl;

x is selected from NR ¹⁴ 、CR ¹⁵ R ¹⁶ Any one of O or S;

the R is ¹⁴ 、R ¹⁵ And R ¹⁶ Independently selected from any one or at least two of hydrogen, deuterium, tritium, cyano-group, nitro-group, halogen, C1-C10 straight-chain alkyl, C3-C10 branched-chain alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, C6-C30 aryl, C6-C30 aryloxy and C3-C30 heteroaryl.

Preferably, Z is ¹ -Z ⁶ Wherein 1-3 (e.g., 2) are N.

Preferably, Z is ⁷ -Z ¹⁴ Wherein 1-3 (e.g., 2) of the (a) groups are N.

Preferably, Z is ¹⁵ -Z ²² Wherein 0-2 (e.g., 1) are N.

Preferably, ar is selected from any one of the following substituted or unsubstituted groups:

the R is ¹⁴ 、R ¹⁵ And R ¹⁶ Each independently selected from any one of hydrogen, deuterium, tritium, cyano, nitro, halogen, C1-C10 alkyl, C1-C10 alkoxy, C6-C30 aryl, C6-C30 aryloxy and C3-C30 heteroaryl.

Preferably, said R is ¹³ 、R ¹⁴ And R ¹⁵ Each independently selected from any one of methyl, phenyl or pyridyl.

Preferably, in Ar, the substituted group is selected from C1-C10 alkyl or C6-C30 aryl, preferably any one or at least two of methyl, phenyl, naphthyl and biphenyl.

In the present invention, the number of carbons in the aryl group (or aromatic ring) includes C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, etc., and the aryl group includes monocyclic, polycyclic, fused ring, and specifically selected from phenyl, biphenyl, terphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, benzofluorenyl, dibenzofluorenyl, phenanthryl, phenylphenanthryl, anthryl, indenyl, triphenylene, pyrenyl, tetracenyl, perylenyl, chrysenyl, fused tetraphenyl, fluoranthryl, or spirobifluorenyl.

In the present invention, the aryloxy group means a group in which an aryl group is bonded to an oxygen atom, wherein the aryl group is as described above.

In the present invention, arylamino means a group in which an aryl group is bonded to an oxygen atom, wherein the aryl group is as described above.

In the present invention, the number of carbons of the heteroaryl group (or heteroaryl ring) includes C4, C5, C6, C7, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, etc., and the heteroaryl group includes a monocyclic ring, a polycyclic ring, and a condensed ring, and the rings may be connected to each other by a short non-aromatic group (e.g., methylene, oxygen, sulfur, nitrogen) or by a single bond, and is selected from the group consisting of furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, benzofuranyl, benzothienyl, isobenzofuranyl, dibenzofuranyl, dibenzothiophenyl, benzothiazolyl, benzisothiazolyl, benzisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, cinnolinyl, quinoxalinyl, dihydrobenzoxazinyl, phenanthrolinyl, and the like, and the derivatives thereof.

In the present invention, the number of carbons in the alkyl group includes C2, C3, C4, C5, C6, C7, C8, C9, and the like, and the alkyl group may be any of a straight chain and a branched chain, and examples thereof include: methyl, ethyl, propyl, isopropyl, butyl, 2-butyl, isobutyl, tert-butyl.

In the present invention, the alkoxy group means a group in which an alkyl group is bonded to an oxygen atom, wherein the alkyl group is as described in the above paragraph.

In the present invention, the carbon number of the alkenyl group includes C2, C3, C4, C5, C6, C7, C8, C9, etc., and the alkenyl group means a monovalent substituent derived from a straight or branched unsaturated hydrocarbon having one or more carbon-carbon double bonds and having 2 to 10 carbon atoms. Examples include, but are not limited to, vinyl, allyl, isopropenyl, 2-butenyl, and the like.

Preferably, the organic electroluminescent compound has any one of the following compounds 1 to 80:

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in the above compounds, D represents deuterium.

It is a second object of the present invention to provide an organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer between the first electrode and the second electrode, the organic layer comprising any one of the organic electroluminescent compounds described in the first object or a combination of at least two of the organic electroluminescent compounds described in the second object.

Preferably, the organic layer includes a light-emitting layer containing the organic electroluminescent compound according to one of the objects.

Preferably, the light emitting layer includes a host material and a guest material, and the host material includes the organic electroluminescent compound according to one of the objects.

Preferably, the light-emitting layer contains at least two host materials.

Preferably, the guest material comprises a fluorescent dopant, preferably any one or a combination of at least two of Ir, pt, ni, au, os, re, rh, zn, ag, fe or W.

Preferably, the organic layer further comprises any one or at least two of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, or an electron injection layer.

Preferably, the electron blocking layer contains an organic electroluminescent compound according to one of the objects.

It is a third object of the present invention to provide a display device or a lighting device including the organic electroluminescent device of the second object.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a novel organic electroluminescent compound, which takes a special condensed ring structure as a mother nucleus, the structure has a certain angle of torsion, the hole transmission rate is reduced to a certain extent, the hole and electron transmission rate balance is facilitated, and when the novel organic electroluminescent compound is applied to an organic electroluminescent device, particularly when the novel organic electroluminescent compound is used as a main body material of a light-emitting layer, the device can have higher luminous efficiency, lower driving voltage and longer service life.

Drawings

Fig. 1 is a schematic structural view of an organic electroluminescent device provided in embodiment 1 of the present invention;

the material comprises a substrate 1, an anode 2, a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, an electron transport layer 6, an electron injection layer 7 and a cathode 8.

Detailed Description

The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

A representative synthetic route for the compounds of formula I of the present invention is as follows (coupling reaction):

wherein X represents a halogen such as fluorine, chlorine, bromine, iodine, etc., and Z ₁ Represents Bpin or B (OH) ₂ ，Z ₂ Represents OH, SH or NO ₂ 。

The following synthetic examples exemplify the synthetic methods of several specific compounds:

synthesis example 1 Synthesis of Compound 20

Synthesis of intermediates 1 to 20: in a 100 ml three-necked flask, raw material 9 (2.75 g, 0.01 mol), raw material 10 (1.84 g, 0.01 mol), potassium carbonate (1.66 g, 0.012 mol), toluene (30 ml), water (6 ml), tetrakis (triphenylphosphine) palladium (5.8 g, 0.5 mmol) were added under nitrogen protection, stirred at 100 ℃ for 10 hours, and cooled to room temperature after reaction. Adding water into a reaction system, extracting by dichloromethane, sequentially adding magnesium sulfate into obtained extract liquor, drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediates 1-20 (0.93 g, 28% yield).

Synthesis of intermediates 2 to 20: the same synthesis as intermediates 1-20 was performed except that intermediates 1-20 (2.87 g, 0.01 mol) were used instead of starting material 9 and starting material 8 (2.18 g, 0.01 mol) was used instead of starting material 10 to give intermediates 2-20 (1.27 g, 31% yield).

Synthesis of intermediates 3 to 20: in a 100 ml three-neck flask, intermediate 2-20 (4.09 g, 0.01 mol), triflic acid (0.02 mol) were added, stirred at 5 ℃ for 2 days, then 20 ml of a mixture of water and pyridine (volume ratio 5) was added, refluxed for half an hour, cooled to room temperature after completion, 50 ml of water was added, extracted with dichloromethane for 3 times, the organic layer was dried over anhydrous magnesium sulfate, the organic solvent was removed, and the product was recrystallized from ethanol to give intermediate 3-20 (1.62 g, 43% yield).

Synthesis of intermediates 4 to 20: in a 100 ml three-necked flask, intermediate 3-20 (3.77 g, 0.01 mol), BOC anhydride (0.012 mol), tetrahydrofuran (35 ml) were added, nitrogen gas was introduced, and after stirring well, 4-dimethylaminopyridine (0.002 mol) was added, the temperature was raised to 70 ℃, reaction was carried out for 2 hours, after cooling to room temperature, the solvent was distilled off under reduced pressure, and the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to give intermediate 4-20 (4.44 g, 93% yield).

Synthesis of intermediates 5 to 20: in a 100 ml three-necked flask, 4-20 (4.77 g, 0.01 mol) of the starting material, anhydrous THF (30 ml) was added under nitrogen, and the reaction was cooled to-78 ℃. N-butyllithium (4.4 ml, 0.025mol) was added under stirring, and the reaction was carried out at this temperature for 1 hour. 9-fluorenone (1.8g, 1mmol) was dissolved in 10ml of anhydrous tetrahydrofuran and added dropwise to the reaction flask. Reacting for 1h at room temperature, adding water into the reaction system, extracting by dichloromethane, and sequentially adding magnesium sulfate into the obtained extract liquid for drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediate 5-20 (4.40 g, 76% yield).

Synthesis of intermediates 6 to 20: in a 100 ml three-necked flask, intermediate 5-20 (5.79 g, 0.01 mol) was added to 20 ml of acetic acid, refluxed for 4 hours, washed with saturated sodium bicarbonate, the organic layer was dried over anhydrous magnesium sulfate, the organic solvent was removed, and the crude product was purified by tetrahydrofuran: ethanol =1, 4, to give intermediates 6-20 (3.96 g, 86% yield).

Synthesis of compound 20: taking a 100 ml double-neck round-bottom flask, putting a stirrer and an upper connecting reflux pipe, introducing nitrogen after drying, and respectively adding an intermediate 6-20 (4.61 g, 0.01 mol), a raw material 5 (2.40 g, 0.01 mol), cesium carbonate (0.012 mol), and tris (dibenzylideneacetone) dipalladium (Pd) ₂ (dba) ₃ 0.5 mmol) and 2-dicyclohexylphosphonium-2 ',4',6' -triisopropylbiphenyl (xphos, 0.55 mmol), followed by addition of toluene, refluxing of the mixture for 24 hours, cooling to room temperature after the reaction, filtration of the reaction system and concentration, and chromatography purification of the crude product (ethyl acetate/n-hexane, 1/10 (volume ratio)) to give compound 20 (5.32 g, yield 80%).

Elemental analysis: c ₄₇ H ₂₇ N ₃ Theoretical value of S: c,84.79, H,4.09, N,6.31, S,4.82, found: c,84.83, H,4.08, N,6.29, S,4.80, HRMS (ESI) M/z (M +): theoretical value: 665.1926, found: 665.1933.

synthesis example 2 Synthesis of Compound 25

Synthesis of intermediates 1 to 25: in a 100 ml three-necked flask, under the protection of nitrogen, raw material 9 (2.75 g, 0.01 mol), raw material 13 (1.80 g, 0.01 mol), potassium carbonate (1.66 g, 0.012 mol), toluene (30 ml), water (6 ml), tetrakis (triphenylphosphine) palladium (5.8 g, 0.5 mmol) were added, stirred at 100 ℃ for 10 hours, and cooled to room temperature after reaction. Adding water into a reaction system, extracting by dichloromethane, and sequentially adding magnesium sulfate into the obtained extract liquor for drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediates 1-25 (1.02 g, 31% yield).

Synthesis of intermediates 2 to 25: the synthesis of intermediates 1-25 was identical except that intermediates 1-25 (3.29 g, 0.01 mol) were used instead of starting material 9 and starting material 8 (2.0 g, 0.01 mol) was used instead of starting material 13 to give intermediates 2-25 (1.22 g, 30% yield).

Synthesis of intermediates 3 to 25: intermediate 2-25 (4.05 g, 0.01 mol), dichloromethane (30 ml) were added in a 100 ml three-necked flask under nitrogen protection, cooled to 0 ℃, a diethyl ether solution (10 ml) of boron trifluoride (0.01 mol) was added dropwise, followed by stirring at room temperature for 12 hours, an aqueous sodium bicarbonate solution was added after the reaction was completed, dichloromethane was extracted, the organic solution was dried over anhydrous magnesium sulfate, and the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to give intermediate 3-25 (1.47 g, 38% yield).

Synthesis of intermediates 4 to 25: in a 100 ml three-necked flask, intermediate 3 to 25 (3.87 g, 0.01 mol), BOC anhydride (0.012 mol), tetrahydrofuran (35 ml) were added, nitrogen gas was introduced, and after stirring uniformly, 4-dimethylaminopyridine (0.002 mol) was added, the temperature was raised to 70 ℃, reaction was carried out for 2 hours, after cooling to room temperature, the solvent was distilled off under reduced pressure, and the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to give intermediate 4 to 25 (4.53 g, 93% yield).

Synthesis of intermediates 5 to 25: in a 100 ml three-neck flask, add starting materials 4-25 (4.87 g, 0.01 mol), anhydrous THF (30 ml) under nitrogen, and cool the reaction to-78 ℃. N-butyllithium (4.4 ml, 0.025mol) was added under stirring, and the reaction was carried out at this temperature for 1 hour. 9-fluorenone (1.8g, 1mmol) was dissolved in 10ml of anhydrous tetrahydrofuran and added dropwise to the reaction flask. Reacting for 1h at room temperature, adding water into the reaction system, extracting by dichloromethane, sequentially adding magnesium sulfate into the obtained extract, drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediate 5-25 (4.18 g, 71% yield).

Synthesis of intermediates 6 to 25: in a 100 ml three-necked flask, intermediate 5-25 (5.89 g, 0.01 mol) was added, 20 ml acetic acid was added, refluxed for 4 hours, washed with saturated sodium bicarbonate, the organic layer was dried over anhydrous magnesium sulfate, the organic solvent was removed, and the crude product was purified by tetrahydrofuran: ethanol =1, recrystallization provided intermediate 6-25 (4.05 g, 86% yield).

Synthesis of compound 25: taking a 100 ml double-neck round-bottom flask, putting a stirrer and an upper connecting reflux pipe, introducing nitrogen after drying, and respectively adding an intermediate 6-25 (4.71 g, 0.01 mol), a raw material 5 (2.40 g, 0.01 mol), cesium carbonate (0.012 mol), and tris (dibenzylideneacetone) dipalladium (Pd) ₂ (dba) ₃ 0.5 mmol) and 2-dicyclohexylphosphonium-2 ',4',6' -triisopropylbiphenyl (xphos, 0.55 mmol), followed by addition of toluene, reflux of the mixture for 24 hours, cooling to room temperature after the reaction, filtration of the reaction system and concentration, and chromatography of the crude product (ethyl acetate/n-hexane, 1/10 (volume ratio)) to give compound 25 (5.13 g, yield 76%).

Elemental analysis: c ₅₀ H ₃₃ N ₃ Theoretical values are as follows: c,88.86, H,4.92, N,6.22, found: c,88.90, H,4.90, N,6.20, HRMS (ESI) M/z (M +): theoretical value: 675.2674, found: 675.2680.

synthesis example 3 Synthesis of Compound 28

Synthesis of intermediates 1 to 28: in a 100 ml three-neck bottle, raw material 1 (2.75 g, 0.01 mol), raw material 2 (1.38 g, 0.01 mol), potassium carbonate (1.66 g, 0.012 mol), toluene (30 ml), water (6 ml), tetrakis (triphenylphosphine) palladium (5.8 g, 0.5 mmol) were added under nitrogen protection, stirred at 100 ℃ for 10 hours, reacted and cooled to room temperature. Adding water into a reaction system, extracting by dichloromethane, and sequentially adding magnesium sulfate into the obtained extract liquor for drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediates 1-28 (0.89 g, 31% yield).

Synthesis of intermediates 2 to 28: the same synthesis as intermediates 1-28 was performed except that intermediates 1-28 (2.87 g, 0.01 mol) were used instead of starting material 1 and starting material 3 (2.18 g, 0.01 mol) was used instead of starting material 2, to give intermediates 2-28 (1.30 g, 34% yield).

Synthesis of intermediates 3 to 28: in a 100 ml three-neck bottle, raw materials 2-28 (3.81 g, 0.01 mol), potassium carbonate (3.45 g, 0.025 mol) and DMF (30 ml) are added under the protection of nitrogen, stirred for 6 hours at 100 ℃, and cooled to room temperature after reaction. Adding water into a reaction system, extracting by dichloromethane, and sequentially adding magnesium sulfate into the obtained extract liquor for drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediates 3-28 (2.89 g, 80% yield).

Synthesis of intermediates 4 to 28: in a 100 ml three-necked flask, intermediate 3 to 28 (3.61 g, 0.01 mol), BOC anhydride (0.012 mol), tetrahydrofuran (35 ml) were added, nitrogen gas was introduced, and after stirring uniformly, 4-dimethylaminopyridine (0.002 mol) was added, the temperature was raised to 70 ℃, reaction was carried out for 2 hours, after cooling to room temperature, the solvent was distilled off under reduced pressure, and the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to give intermediate 4 to 28 (4.15 g, yield 90%).

Synthesis of intermediates 5 to 28: the starting materials 4-28 (4.61 g, 0.01 mol), anhydrous THF (30 ml) were added under nitrogen in a 100 ml three-neck flask and the reaction was cooled to-78 ℃. N-butyllithium (4.4 ml, 0.025mol) was added under stirring, and the reaction was carried out at this temperature for 1 hour. 9-fluorenone (1.8g, 1mmol) was dissolved in 10ml of anhydrous tetrahydrofuran and added dropwise to the reaction flask. Reacting for 1h at room temperature, adding water into the reaction system, extracting by dichloromethane, and sequentially adding magnesium sulfate into the obtained extract liquid for drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediates 5-28 (4.50 g, 80% yield).

Synthesis of intermediates 6 to 28: in a 100 ml three-necked flask, intermediate 5-28 (5.63 g, 0.01 mol) was added, 20 ml acetic acid was added, refluxed for 4 hours, washed with saturated sodium bicarbonate, the organic layer was dried over anhydrous magnesium sulfate, the organic solvent was removed, and the crude product was purified by tetrahydrofuran: ethanol =1, recrystallization from 4 afforded intermediates 6-28 (4.0 g, 90% yield).

Synthesis of compound 28: taking a 100 ml double-neck round-bottom flask, putting a stirrer and an upper connecting reflux pipe, introducing nitrogen after drying, and respectively adding an intermediate 6-28 (4.45 g, 0.01 mol), a raw material 5 (2.40 g, 0.01 mol), cesium carbonate (0.012 mol), and tris (dibenzylideneacetone) dipalladium (Pd) ₂ (dba) ₃ 0.5 mmol) and 2-dicyclohexylphosphorus-2 ',4',6' -triisopropylbiphenyl (xphos, 0.55 mmol) were added, toluene was then added, the mixture was refluxed for 24 hours, cooled to room temperature after the reaction, the reaction system was filtered and concentrated, and the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain compound 28 (5.45 g, 84% yield).

Elemental analysis: c ₄₇ H ₂₇ N ₃ Theoretical value of O: c,86.88, H,4.19, N,6.47, found: c,86.93, H,4.17, N,6.45, HRMS (ESI) M/z (M +): theoretical value: 649.2154, found: 649.2159.

synthesis example 4 Synthesis of Compound 34

Synthesis of intermediates 1 to 34: the synthesis of intermediates 1-28 was identical except starting material 6 (2.92 g, 0.01 mol) was used instead of starting material 1 and starting material 7 (1.67 g, 0.01 mol) was used instead of starting material 2 to give intermediates 1-34 (1.40 g, 42% yield).

Synthesis of intermediates 2 to 34: the same synthesis as intermediates 1-28 was performed except that intermediate 1-34 (3.33 g, 0.01 mol) was used instead of starting material 1 and starting material 8 (2.00 g, 0.01 mol) was used instead of starting material 2 to give intermediates 2-34 (1.43 g, 35% yield).

Synthesis of intermediates 3 to 34: taking a 100 ml double-neck round-bottom bottle, putting a stirrer and an upper reflux pipe, drying, introducing nitrogen, respectively adding an intermediate 2-34 (4.09 g, 0.01 mol), triphenylphosphine (0.02 mol) and 1, 2-dichlorobenzene (40 ml), heating at 180 ℃ for reaction for 12 hours, cooling to room temperature after the reaction is finished, concentrating a reaction system, and purifying a crude product by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain an intermediate 3-34 (2.79 g, yield 74%).

Synthesis of intermediates 4 to 34: the synthesis of intermediate 3-28 was identical except that intermediate 3-34 (3.77 g, 0.01 mol) was used instead of intermediate 3-28 to give intermediate 4-34 (4.58 g, 96% yield).

Synthesis of intermediates 5 to 34: the synthesis of intermediates 4-28 was repeated except that intermediate 4-34 (4.77 g, 0.01 mol) was used instead of intermediate 4-28 to give intermediates 5-34 (4.57 g, 79% yield).

Synthesis of intermediates 6 to 34: the same synthesis as intermediate 5-28 was performed except that intermediate 5-34 (5.79 g, 0.01 mol) was used instead of intermediate 5-28 to give intermediate 6-34 (4.33 g, 94% yield).

Synthesis of compound 34: synthesis of Compound 28 was performed except that intermediates 6-34 (4.61 g, 0.01 mol) were used instead of intermediates 6-28 to give Compound 34 (5.79 g, 87% yield).

Elemental analysis: c ₄₇ H ₂₇ N ₃ Theoretical value of S: c,84.79, H,4.09, N,6.31, S,4.82, found: c,84.84, H,4.08, N,6.28, S,4.80, HRMS (ESI) M/z (M +): theoretical value: 665.1926, found: 665.1932.

synthesis example 5 Synthesis of Compound 54

Synthesis of intermediates 1 to 54: synthesis of compound 28 except that 6-28 (4.45 g, 0.01 mol) was used instead of intermediates 7-28 and starting material 11 (2.04 g, 0.01 mol) was used instead of starting material 5 gave intermediates 1-54 (4.64 g, 89% yield).

Synthesis of intermediates 2 to 54: a100 ml double-neck round-bottom bottle is taken, a stirrer and an upper connecting reflux pipe are placed in the bottle, nitrogen is filled after drying, intermediates 1 to 54 (5.21 g, 0.01 mol), N-bromosuccinimide (0.011 mol) and 40 ml tetrahydrofuran are respectively added, and stirring is carried out for 10 hours at room temperature. After the reaction was complete, 5 ml of water were added. Extracting the reaction system for three times by using dichloromethane, and sequentially adding magnesium sulfate into the obtained extract liquor for drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/hexane, 1/10) to afford intermediates 2-54 (4.07 g, 68% yield).

Synthesis of intermediates 3 to 54: in a 100 ml three-neck flask, the intermediates 2-54 (5.99 g, 0.01 mol), the raw material 7 (1.67 g, 0.01 mol), potassium carbonate (1.66 g, 0.012 mol), toluene (30 ml), water (6 ml), tetrakis (triphenylphosphine) palladium (5.8 g, 0.5 mmol) were added under nitrogen protection, stirred at 100 ℃ for 10 hours, reacted and cooled to room temperature. Adding water into a reaction system, extracting by dichloromethane, sequentially adding magnesium sulfate into obtained extract liquor, drying, filtering and spin-drying; the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10) to afford intermediate 3-54 (4.94 g, 77% yield).

Synthesis of intermediates 4 to 54: taking a 100 ml double-neck round-bottom bottle, putting a stirrer and an upper reflux pipe, drying, introducing nitrogen, respectively adding the intermediates 3-54 (6.42 g, 0.01 mol), triphenylphosphine (0.02 mol) and 1, 2-dichlorobenzene (40 ml), heating at 180 ℃ for reaction for 12 hours, cooling to room temperature after the reaction is finished, concentrating the reaction system, and purifying the crude product by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain the intermediates 4-54 (5.12 g, 84% yield).

Synthesis of compound 54: synthesis of compound 28 except that intermediate 7-28 was replaced with 4-54 (6.10 g, 0.01 mol) and starting material 5 was replaced with starting material 11 (2.04 g, 0.01 mol) gave compound 54 (5.90 g, 86% yield).

Elemental analysis: c ₅₁ H ₃₀ N ₂ Theoretical value of O: c,89.19, H,4.40, N,4.08, found: c,89.23, H,4.38, N,4.07, HRMS (ESI) M/z (M +): theoretical values are as follows: 686.2358, found: 686.2364.

synthesis example 6 Synthesis of Compound 72

Synthesis of intermediates 1 to 72: synthesis of intermediates 1-28 starting material 7 (1.67 g, 0.01 mol) was substituted for starting material 2 to give intermediates 1-72 (1.01 g, 32% yield).

Synthesis of intermediates 2 to 72: the synthesis of intermediates 1-28 was identical except that starting material 1 was replaced with intermediates 1-72 (3.16 g, 0.01 mol) and starting material 2 was replaced with starting material 8 (2.00 g, 0.01 mol) to give intermediates 2-72 (1.29 g, 33% yield).

Synthesis of intermediates 3 to 72: taking a 100 ml double-neck round-bottom bottle, putting a stirrer and an upper reflux pipe, drying, introducing nitrogen, respectively adding an intermediate 2-72 (3.92 g, 0.01 mol), triphenylphosphine (0.02 mol) and 1, 2-dichlorobenzene (40 ml), heating at 180 ℃ for reaction for 12 hours, cooling to room temperature after the reaction is finished, concentrating a reaction system, and purifying a crude product by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain an intermediate 3-72 (2.56 g, 71% yield).

Synthesis of intermediates 4 to 72: the synthesis was identical to that of intermediate 3-28, except that intermediate 3-72 (3.60 g, 0.01 mol) was used instead of intermediate 3-28, giving intermediate 4-72 (5.38 g, 96% yield).

Synthesis of intermediates 5-72: the same synthesis as intermediate 4-28 was performed except that intermediate 4-72 (5.60 g, 0.01 mol) was used instead of intermediate 4-28 to give intermediate 5-72 (4.90 g, 74% yield).

Synthesis of intermediates 6 to 72: the synthesis was identical to that of intermediate 5-28, except that intermediate 5-72 (6.62 g, 0.01 mol) was used instead of intermediate 5-28, giving intermediate 6-72 (4.22 g, 95% yield).

Synthesis of compound 72: synthesis of compound 28 was performed except that intermediates 7-28 were replaced with intermediates 7-72 (4.44 g, 0.01 mol) and starting material 5 was replaced with starting material 11 (1.12 g, 0.01 mol) to give compound 72 (5.24 g, 88% yield).

Elemental analysis: c ₄₅ H ₂₈ N ₂ Theoretical values are as follows: c,90.58, H,4.73, N,4.69, found: c,90.62, H,4.71, N,4.67, HRMS (ESI) M/z (M +): theoretical value: 596.2252, found value：596.2259。

Synthesis example 7 Synthesis of Compound 5

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Synthesis of intermediates 8 to 5: a100 ml two-necked round-bottom flask was taken, a stirrer and an upper reflux pipe were placed, nitrogen was introduced after drying, intermediate 7 to 72 (4.44 g, 0.01 mol), raw material 12 (2.67 g, 0.01 mol), cesium carbonate (0.012 mol), tris (dibenzylideneacetone) dipalladium (Pd 2 (dba) 3,0.5 mmol) and 2-dicyclohexylphosphorus-2 ',4',6' -triisopropylbiphenyl (xphos, 0.55 mmol) were added, toluene was then added, the mixture was refluxed for 18 hours, cooled to room temperature after reaction, and concentrated after filtration of the reaction system, and the crude product was purified by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain intermediate 8 to 5 (3.17 g, yield 47%).

Synthesis of Compound 5: a100 ml two-neck round-bottom flask is taken and placed with a stirrer and an upper reflux pipe, nitrogen is filled after drying, intermediate 8-5 (6.75 g, 0.01 mol), raw material 11 (1.12 g, 0.01 mol), 1' -bis (diphenylphosphino) ferrocene) dichloropalladium (II) (0.5 mmol), 10% palladium-carbon (0.5 mmol), trimethylbenzene (50 ml), sodium tert-butoxide (0.01 mol) are respectively added, the mixture is refluxed for 24 hours, cooled to room temperature after reaction, a reaction system is filtered and concentrated, and a crude product is purified by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain compound 5 (6.68 g, 89% yield).

Elemental analysis: c ₅₄ H ₃₃ N ₅ Theoretical value: c,86.26, H,4.42, N,9.31, found: c,86.21, H,4.44, N,9.35, HRMS (ESI) M/z (M +): theoretical value: 751.2736, found: 751.2745.

synthesis example 8 Synthesis of Compound 77

Synthesis of intermediates 1 to 77: the synthesis of intermediates 1-28 was identical except starting material 14 (3.02 g, 0.01 mol) was used instead of starting material 1 and starting material 7 (1.67 g, 0.01 mol) was used instead of starting material 2 to give intermediates 1-77 (1.37 g, 40% yield).

Synthesis of intermediates 2 to 77: the synthesis was identical to intermediates 1-28 except that intermediate 1-77 (3.43 g, 0.01 mol) was used instead of starting material 1 and starting material 8 (2.00 g, 0.01 mol) was used instead of starting material 2 to give intermediates 2-77 (1.42 g, 34% yield).

Synthesis of intermediates 3 to 77: taking a 100 ml double-neck round-bottom bottle, putting a stirrer and an upper reflux pipe, drying, introducing nitrogen, respectively adding an intermediate 2-77 (4.19 g, 0.01 mol), triphenylphosphine (0.02 mol) and 1, 2-dichlorobenzene (40 ml), heating at 180 ℃ for reaction for 12 hours, cooling to room temperature after the reaction is finished, concentrating a reaction system, and purifying a crude product by chromatography (ethyl acetate/n-hexane, 1/10 (volume ratio)) to obtain an intermediate 3-77 (2.71 g, yield 70%).

Synthesis of intermediates 4 to 77: the synthesis was identical to that of intermediate 3-28, except that intermediate 3-77 (3.87 g, 0.01 mol) was used instead of intermediate 3-28, giving intermediate 4-77 (4.63 g, 95% yield).

Synthesis of intermediates 5 to 77: the synthesis was identical to that of intermediates 4-28 except that intermediate 4-77 (4.87 g, 0.01 mol) was used instead of intermediate 4-28 to give intermediates 5-77 (4.48 g, 76% yield).

Synthesis of intermediates 6 to 77: the synthesis was identical to that of intermediates 5-28, except that intermediate 5-77 (5.89 g, 0.01 mol) was used instead of intermediate 5-28, giving intermediate 6-77 (4.33 g, 92% yield).

Synthesis of compound 77: the synthesis of compound 28 was performed except that intermediate 6-77 (4.71 g, 0.01 mol) was used instead of intermediate 6-28 to give compound 77 (5.98 g, 88% yield).

Elemental analysis: c ₅₀ H ₂₈ N ₃ D ₅ Theoretical values are as follows: c,88.20, H,5.62, N,6.17, found: c,88.17, H,5.64, N,6.19, HRMS (ESI) M/z (M +): theoretical values are as follows: 680.2988, found: 680.2995.

example 1

The present embodiment provides an organic electroluminescent device comprising an anode 2, a hole injection layer 3, a hole transport layer 4, a light emitting layer 5, an electron transport layer 6, an electron injection layer 7 and a cathode 8, which are sequentially stacked and disposed on a substrate 1, as shown in fig. 1.

The anode 2 is made of ITO material;

the hole injection layer 3 is HAT (CN) ₆ And NPB, wherein HAT (CN) ₆ : NPB =3 (mass ratio);

the hole transport layer 4 is NPB;

the light-emitting layer 5 is composed of a host material and a dopant material, the host material is the compound 28 synthesized in Synthesis example 1, and the guest material is Ir (DBQ) ₂ (acac), the mass ratio of the host material to the guest material is 95;

the electron transmission layer 6 is selected from BPhen and LiQ, wherein the BPhen: liQ =1:1 (mass ratio);

the electron injection layer 7 is LiQ;

the cathode 8 is made of Mg/Ag, wherein the mass ratio of Mg to Ag = 9.

The specific preparation method of the organic electroluminescent device comprises the following steps:

(1) Substrate cleaning: carrying out ultrasonic treatment on the transparent ITO coated motor substrate in an aqueous cleaning agent (the components and concentration of the aqueous cleaning agent are that ethylene glycol solvent is less than or equal to 10wt% and triethanolamine is less than or equal to 1 wt%), washing in deionized water, carrying out ultrasonic oil removal in a mixed solvent of acetone and ethanol (volume ratio is 1;

(2) Vapor deposition: placing the glass substrate with anode layer in a vacuum chamber, and vacuumizing to 1 × 10 ^-6 To 2×10 ^-4 Pa, vacuum evaporating hole injection material HAT (CN) on the anode layer film by co-evaporation ₆ Adjusting the rate with NPB according to the mass ratio, wherein the total evaporation rate is 0.1nm/s, and the evaporation thickness is 10nm;

(3) Evaporating a hole transport layer on the hole injection layer at the evaporation rate of 0.1nm/s and the evaporation film thickness of 80nm;

(4) Evaporating a luminescent layer on the hole transport layer, and evaporating luminescent host materials and guest materials in a vacuum evaporation mode, wherein the evaporation rate of the host materials and the guest materials is adjusted according to the mass ratio, the total evaporation rate is 0.01nm/s, and the total evaporation film thickness is 40nm;

(5) Vacuum evaporating an electron transport layer on the luminescent layer, and adjusting the evaporation rate according to the mass ratio, wherein the total evaporation rate is 0.1nm/s, and the total evaporation film thickness is 30nm;

(6) Vacuum evaporating an electron injection layer on the electron transmission layer, wherein the evaporation rate is 0.05nm/s, and the total film thickness is 1nm;

(7) Mg/Ag is used as a cathode layer of the device, the evaporation rate is adjusted according to the mass ratio, the total evaporation rate is 0.1nm/s, and the total evaporation film thickness is 80nm.

Example 2

The difference compared to example 1 is that the host material replaces compound 28 with compound 34.

Example 3

The difference compared to example 1 is that the host material replaces compound 28 with compound 60.

Example 4

The difference from example 1 is that an electron blocking layer was added between the light-emitting layer and the hole transporting layer, and the electron resistance used as the material was compound 54 and had a thickness of 5nm.

Example 5

The difference from example 1 is that an electron blocking layer was added between the light-emitting layer and the hole transporting layer, and the electron blocking layer used was the compound 72 and had a thickness of 5nm.

Example 6

The difference compared to example 1 is that the host material is compound 5 instead of compound 28.

Comparative example 1

The difference compared to example 1 is that the host material has CBP instead of compound 28.

Comparative example 1

The difference compared to example 1 is that the host material is compound D1 (US 20160351825 A1) instead of compound 28.

Test example 1

Measurement of thermal decomposition temperature:

thermal decomposition temperature test was performed on the fused cyclic compound material using a thermogravimetric analyzer (TA TGA55 in USA) with a temperature range of room temperature to 600 deg.C, a temperature rise rate of 10 deg.C/min, and a temperature at which 5% of weight loss is defined as a thermal decomposition temperature (T) under a nitrogen atmosphere _d ) The measurement results are shown in table 1:

TABLE 1

Compound (I)	T _d (℃)
		28	384
34	391
		54	418
72	356
		5	453
20	388
		25	394
77	397

Test example 2

Testing HOMO and LOMO energy levels:

the LUMO energy levels of the fused ring compound materials prepared in synthesis examples 1 to 8 were measured using an electrochemical workstation using cyclic voltammetry (CV shanghai chen CHI-600E) using a platinum wire (Pt) as a counter electrode and silver/silver chloride (Ag/AgCl) as a reference electrode. In the nitrogen atmosphere, the test is carried out in methylene dichloride electrolyte containing 0.1M tetrabutylammonium hexafluorophosphate at the scanning rate of 100mV/s, the potential calibration is carried out by ferrocene, and the absolute energy level of the potential of the ferrocene in the vacuum state is set as-4.8 eV:

HOMO _{energy level} ＝-e(Eox-E _{1/2,ferrocene} )+(-4.8)eV

LUMO _{Energy level} ＝-e(Ere-E _{1/2,ferrocene} )+(-4.8)eV

E _T1 (eV) triplet level.

Eox is oxidation potential, ere is reduction potential, E _{1/2,ferrocene} Is the ferrocene potential. Triplet state energy level test conditions: spectrofluorometer (Hitachi F-4600), solution state (toluene as solvent, concentration 2X 10) ^-5 mol/L) and 78 degrees centigrade.

E _T1 = 1240/shortest absorptionWavelength of light

The measurement results are shown in table 2:

TABLE 2

Host material	HOMO(eV)	LUMO(eV)	E _T1 (eV)
				28	-5.54	-2.84	2.21
34	-5.51	-2.83	2.20
				54	-5.40	-2.79	2.31
72	-5.38	-2.78	2.29
				5	-5.37	-2.76	2.18
20	-5.57	-2.84	2.23
				25	-5.55	-2.82	2.20
77	-5.60	-2.85	2.25

Test example 3

The following tests were carried out for the organic electroluminescent devices provided in the above examples and comparative examples:

the characteristics of the device such as current, voltage, brightness, luminescence spectrum and the like are synchronously tested by adopting a PR 650 spectrum scanning luminance meter and a Keithley K2400 digital source meter system, and the test conditions are as follows: the current density is 20mA/cm ² Room temperature;

and (3) life test: the time (in hours) was recorded when the device brightness dropped to 95% of the original brightness.

The results are shown in Table 3.

TABLE 3

Wherein-represents that no electron blocking layer is provided.

As can be seen from the data in tables 1 to 3, the organic electroluminescent compound provided by the present invention has high thermal stability, a high triplet level can be used as an electron blocking layer material to prevent electrons from entering a hole blocking layer from a light emitting layer and to avoid efficiency roll-off, and appropriate HOMO and LUMO levels match with the energy levels of adjacent layer materials, so that the device has high light emitting efficiency, low driving voltage, and long service life. The host material of comparative example 1 is different from that of example 5 only in the parent nucleus, but it has higher voltage, lower current efficiency, and lower lifespan than example 5.

The applicant states that the present invention is illustrated in detail by the above examples, but the present invention is not limited to the above detailed methods, i.e. it is not meant that the present invention must rely on the above detailed methods for its implementation. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims

1. An organic electroluminescent compound, characterized in that the organic electroluminescent compound has a structure represented by formula I;

in the formula I, the Y ¹ And Y ² Each independently selected from N-L-Ar, O, S or CR _a R _b Said R is _a And R _b Are not connected with each other; y is ¹ 、Y ² At least one of them is N-L-Ar;

ar is selected from substituted or unsubstituted phenyl, substituted or unsubstituted quinazolinyl or substituted or unsubstituted triazinyl;

in the substituted quinazoline group, the substituted triazine group and the substituted phenyl group, the substituent is selected from phenyl or deuterium substituted phenyl, biphenyl, naphthyl, fluorenyl, pyridyl or dibenzofuranyl;

the R is _a And R _b Each independently selected from methyl or phenyl;

in the formula I, R is ¹ 、R ² 、R ³ 、R ⁴ Is hydrogen, R ⁵ Is hydrogen or R ⁵ Adjacent groups on the same benzene ring are connected to form substituted or unsubstituted carbazolyl, and the substituent is phenyl or pyridyl;

l is selected from single bond and phenyl;

in the formula I, m is 1, k is 2, n, p and q are 1.

2. The organic electroluminescent compound according to claim 1, wherein the organic electroluminescent compound has a structure represented by formula II or formula III;

said X ¹ And X ² Each independently is any one of a single bond and N-L-Ar, X ¹ And X ² Has one and only one single bond;

r and s are each independently an integer of 0 to 4;

r 'is selected from hydrogen, phenyl or pyridyl, R' is selected from hydrogen;

ar is phenyl or pyridyl, L is a single bond, Y ¹ 、Y ² 、R ¹ -R ⁴ M, n, p and q all have the same limitations as in claim 1.

3. The organic electroluminescent compound according to claim 2, wherein in formula III, Y is ¹ And Y ² The two terms are N-L-Ar.

4. An organic electroluminescent compound, characterized in that the organic electroluminescent compound has any one of the following compounds:

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d represents deuterium.

5. An organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer between the first electrode and the second electrode, wherein the organic layer comprises any one or a combination of at least two of the organic electroluminescent compounds according to any one of claims 1 to 4.

6. The organic electroluminescent device according to claim 5, wherein the organic layer comprises a light-emitting layer containing the organic electroluminescent compound according to any one of claims 1 to 4.

7. The organic electroluminescent device according to claim 6, wherein the light-emitting layer comprises a host material and a guest material, and the host material comprises the organic electroluminescent compound according to any one of claims 1 to 4.

8. The organic electroluminescent device according to claim 7, wherein the light-emitting layer contains at least two host materials.

9. The organic electroluminescent device of claim 7, wherein the guest material comprises a fluorescent dopant.

10. The organic electroluminescent device according to claim 9, wherein the fluorescent dopant is selected from any one or a combination of at least two of Ir, pt, ni, au, os, re, rh, zn, ag, fe, or W.

11. The organic electroluminescent device according to claim 5, wherein the organic layer further comprises any one or a combination of at least two of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, or an electron injection layer.

12. The organic electroluminescent device according to claim 11, wherein the organic electroluminescent compound according to any one of claims 1 to 4 is contained in the electron blocking layer.

13. A display device or a lighting device comprising the organic electroluminescent device according to any one of claims 5 to 12.