WO2023273997A1 - Organic compound and application thereof - Google Patents

Abstract

An organic compound and an application thereof. The organic compound has a structure represented by formula I, has better stability and photoelectric properties, and can enhance and balance carrier transport, thereby improving device performance. The organic compound is used as an electron blocking layer material of an organic light-emitting diode (OLED) device, and can reduce the driving voltage of the device and improve the luminous efficiency, so that the OLED device has better comprehensive performance. In addition, according to the organic compound, the preparation method is simple, the raw materials are easily available, and large-scale mass production is easy to be realized.

Description

A kind of organic compound and its application

Cross References to Related Applications

This application claims the priority of the Chinese patent application with the application number 202110719937.4 and the application title "An Organic Compound and Its Application" submitted to the China Patent Office on June 28, 2021, the entire contents of which are incorporated by reference in this application .

technical field

The application belongs to the technical field of organic electroluminescent materials, and specifically relates to an organic compound and its application.

Background technique

Organic Light Emission Diodes (OLED) devices are emerging display technologies in recent years. They have the characteristics of high brightness, fast response, low energy consumption, wide viewing angle, flexibility, wide temperature range, and simple process. It is widely used in the display panels of products such as lighting fixtures, smart phones and tablet computers, and further expands to the application fields of large-size display products such as TVs.

The OLED device has a sandwich-like structure, including positive and negative electrodes and an organic functional material layer sandwiched between the two electrodes; when a voltage is applied to the electrodes of the OLED device, electrons and holes are respectively injected, transported to the light-emitting region and recombined there , thereby generating excitons and emitting light. The core of an OLED device is an organic functional material layer. The common organic functional materials that make up the material layer include: hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, and light-emitting hosts. Materials and luminescent guests (dye), etc.

Common fluorescent emitters mainly use singlet excitons generated when electrons and holes combine to emit light, and are still widely used in various OLED products. Some metal complexes (such as iridium complexes) can simultaneously utilize triplet excitons and singlet excitons to emit light, which are called phosphorescent emitters, and their energy conversion efficiency can be up to four times higher than that of traditional fluorescent emitters. Thermally Excited Delayed Fluorescence (TADF) technology promotes the transformation of triplet excitons to singlet excitons, and can still effectively utilize triplet excitons to achieve high luminous efficiency without using metal complexes. Thermally-stimulated sensitized fluorescence (TASF) technology uses materials with TADF properties to sensitize light emitters through energy transfer, and can also achieve higher luminous efficiency.

The hole transport material has a significant impact on the performance of the device. On the one hand, the hole transport material needs to have a suitable HOMO energy level, and a suitable energy gap between the hole material and the anode is conducive to the injection of holes and can help reduce the operating voltage. On the other hand, the hole transport material regulates the transport balance of carriers in the device and improves the carrier mobility of the hole transport material, thereby improving the luminous efficiency and delaying the decay of the device. Although products using OLED display technology have been commercialized, there are still requirements for further improvement in terms of device efficiency and service life.

Therefore, there is an urgent need to develop more types of organic materials with higher performance in this field to improve the performance of organic electroluminescent devices, so that the devices have higher luminous efficiency and lower driving voltage.

Contents of the invention

In view of the deficiencies in the prior art, the purpose of this application is to provide an organic compound and its application. The organic compound is applied to an organic electroluminescent device, and is especially suitable as an electron blocking layer material and/or a hole transporting layer material, The luminous efficiency of the device can be improved and the driving voltage can be reduced.

For this purpose, the application adopts the following technical solutions:

One of the purposes of the present application provides a kind of organic compound, and described organic compound has structure as shown in formula I:

In formula I, Ar ¹ and Ar ² are each independently selected from any one of substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups.

In formula I, Ar ³ is selected from any one of substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted C3-C11 heteroaryl.

In formula I, X is selected from any one of O, S, CR ¹ R ² , NR ³ or SiR ⁴ R ⁵ .

R ¹ , R ² , R ³ , R ⁴ , and R ⁵ are each independently selected from hydrogen, substituted or unsubstituted C1-C20 linear or branched chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted Or any of unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

R ¹ and R ² are not connected or are connected to form a ring by a chemical bond, R ⁴ and R ⁵ are not connected or are connected to form a ring by a chemical bond;

R _f1 , R _f2 , and R _f3 are each independently selected from halogen, cyano, substituted or unsubstituted C1-C20 linear or branched chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted Any one of C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

Ar ¹ , Ar ² , R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R _f1 , R _f2 , and R _f3 are each independently selected from halogen, C1-C10 straight chain or branched Alkanyl, C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, C1-C10 alkoxy, C1-C10 alkylthio, C6-C30 arylamino, C3-C30 heteroarylamino, C6- At least one of C30 aryl or C3-C30 heteroaryl;

The substituted substituent in Ar ³ is at least one selected from halogen, C1-C6 linear or branched chain alkyl, C3-C6 cycloalkyl, C1-C6 alkoxy or C1-C6 alkylthio.

k ₁ and k ₂ are each independently an integer of 0-3, such as 0, 1, 2 or 3; k ₃ is an integer of 0-4, such as 0, 1, 2, 3 or 4.

The organic compound provided by this application has a structure as shown in formula I. Through the design of the molecular structure, the arylamine N is directly connected to the condensed structure of the dibenzo five-membered ring, which is conducive to the improvement of the mobility, and the molecular packing is denser; and N is connected to the 2-position of the dibenzo five-membered ring fused structure, which can further improve the mobility and performance of the device; N, Ar ¹ and Ar ² are located adjacent to the benzene ring, which can make the LUMO energy The level becomes shallow, thereby further blocking the diffusion of excitons to the hole layer, and improving the performance of the device; at the same time, the Ar ³ is selected from C6-C12 aryl or C3-C11 heteroaryl with a smaller molecular weight, which is beneficial to the overall molecular weight of the compound Controlling, so as to avoid excessive evaporation temperature in the device preparation process due to excessive molecular weight, which is more conducive to production. The organic compound is used in an organic electroluminescent device, and as an electron blocking layer material and/or a hole transporting layer material, it can effectively reduce the driving voltage of the device and improve luminous efficiency.

It should be noted that, for the convenience of explanation, the possible functions of each group/feature are described separately in this application, but this does not mean that these groups/features function in isolation. In fact, the reason for obtaining good performance is essentially the optimized combination of the entire molecule, which is the result of the synergistic effect between the various groups, rather than the effect of a single group.

In the present application, the halogens can all be fluorine, chlorine, bromine or iodine. The following descriptions refer to the same, and all have the same meaning.

In the present application, the "substituted or unsubstituted" group may be substituted with one substituent, or may be substituted with multiple substituents. When there are multiple substituents (at least 2), they may be the same or different Substituents; when the same expressions are mentioned below, they all have the same meaning, and the selection range of the substituents is as shown above, and will not be repeated.

In this application, for the expression of chemical elements, unless otherwise specified, the concept of isotopes with the same chemical properties is included, for example, hydrogen (H) includes ¹ H (protium), ² H (deuterium, D), ³ H ( tritium, T), etc.; carbon (C) includes ¹² C, ¹³ C, etc.

In the present application, unless otherwise specified, the heteroatoms of the heteroaryl group are selected from N, O, S, P, B, Si or Se.

In the present application, the expression of the ring structure crossed by "—" indicates that the linking site is at any position on the ring structure that can form a bond.

In the present application, the expression of Ca-Cb means that the number of carbon atoms of the group is a-b, unless otherwise specified, generally speaking, the number of carbon atoms does not include the number of carbon atoms of the substituent.

In this specification, "each independently" means that when there are plural subjects, they may be the same or different from each other.

In the present application, the C6-C30 can all be C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

The C3-C30 can all be C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

The C6-C12 can all be C6, C9, C10, or C12, etc.; the C3-C11 can all be C3, C4, C5, C6, C9, or C10, etc.

The C1-C20 can all be C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C19, etc.

The C3-C20 can all be C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C19, etc.

The C2-C12 can all be C3, C4, C5, C6, C7, C8, C9, C10 or C11, etc.

The C1-C10 can all be C1, C2, C3, C4, C5, C6, C7, C8, C9 or C10.

The C3-C10 can all be C3, C4, C5, C6, C7, C8, C9 or C10.

The C2-C10 can all be C2, C3, C4, C5, C6, C7, C8, C9 or C10.

The C1-C6 can all be C1, C2, C3, C4, C5 or C6; the C3-C6 can all be C3, C4, C5 or C6.

基或并四苯基等。 In the present application, the C6-C30 aryl group, preferably C6-C20 aryl group, includes a single-ring aryl group and a fused-ring aryl group; the single-ring aryl group means that the group contains at least one phenyl group, when containing When there are at least two phenyl groups, the phenyl groups are connected by a single bond, exemplarily including but not limited to: phenyl, biphenyl, terphenyl, etc.; the condensed aromatic group means that the group contains at least 2 two aromatic rings, and two adjacent carbon atoms are fused together between the aromatic rings, examples include but not limited to: naphthyl, anthracenyl, phenanthrenyl, indenyl, fluorenyl and derivatives thereof (9,9-Dimethylfluorenyl, 9,9-diethylfluorenyl, 9,9-dipropylfluorenyl, 9,9-dibutylfluorenyl, 9,9-dipentylfluorenyl , 9,9-dihexylfluorenyl, 9,9-diphenylfluorenyl, 9,9-dinaphthylfluorenyl, spirobifluorenyl, benzofluorenyl, etc.), fluoranthenyl, triphenylene, pyrenyl, perylene,

base or naphthacene, etc.

The C3-C30 heteroaryl includes monocyclic heteroaryl and condensed ring heteroaryl. The monocyclic heteroaryl group means that the molecule contains at least one heteroaryl group. When the molecule contains a heteroaryl group and other groups (such as aryl, heteroaryl, alkyl, etc.), the heteroaryl group and other The groups are connected by a single bond, exemplarily including but not limited to: furyl, thienyl, pyrrolyl, pyridyl and the like. The fused-ring heteroaryl group means a group that contains at least one aromatic heterocycle and one aromatic ring (aromatic heterocycle or aromatic ring) in the molecule, and the two share two adjacent atoms that are fused to each other. Exemplary Including but not limited to: benzofuryl, benzothienyl, isobenzofuryl, isobenzothienyl, indolyl, dibenzofuryl, dibenzothienyl, carbazolyl and derivatives thereof (for example, the carbazolyl and its derivatives can be N-phenylcarbazolyl, N-naphthylcarbazolyl, benzocarbazolyl, dibenzocarbazolyl, indolocarbazolyl , azacarbazolyl, etc.), acridinyl, phenothiazinyl, phenoxazinyl, hydrogenated acridinyl, etc.

Specific examples of the arylene group described below in the present application may include divalent groups obtained by removing one hydrogen atom from the above-mentioned aryl group; specific examples of the heteroarylene group may include the above-mentioned heteroaryl group The divalent group obtained by removing a hydrogen atom in the example.

The C1-C20 straight-chain or branched-chain alkyl, exemplary includes but not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl , isopentyl, neopentyl, n-hexyl, n-octyl, n-heptyl, n-nonyl, n-decyl, etc.

The C3-C20 cycloalkyl group exemplarily includes, but is not limited to: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl and the like.

Preferably, the Ar ¹ and Ar ² are each independently selected from any one of substituted or unsubstituted C6-C20 aryl groups, substituted or unsubstituted C10-C20 fused ring heteroaryl groups.

Preferably, the Ar ¹ and Ar ² are each independently selected from any of the following substituted or unsubstituted groups:

Wherein, * represents the connection site of the group;

Z is selected from any one of O, S, CR ¹¹ R ¹² , NR ¹³ or SiR ¹⁴ R ¹⁵ ;

R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ are each independently selected from hydrogen, substituted or unsubstituted C1-C20 linear or branched chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted Or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl.

R ¹¹ and R ¹² are not connected or are connected to form a ring through a chemical bond, and R ¹⁴ and R ¹⁵ are not connected or are connected to form a ring through a chemical bond.

Preferably, the R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ are each independently methyl or phenyl; R ¹¹ and R ¹² are not connected or connected to form a ring through a chemical bond (a fluorene ring), and R ¹⁴ and R ¹⁵ are not connected or connected by a chemical bond to form a ring.

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

Among them, * represents the linking site of the group.

其中，*代表基团的连接位点。 Preferably, the Ar is selected from any one of the following substituted or unsubstituted groups ^:

Among them, * represents the linking site of the group.

Preferably, the Ar ¹ and Ar ² are not simultaneously phenyl.

Preferably, the ^Ar3 is substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, and the substituted substituent is selected from halogen, C1-C6 straight chain or branched chain alkyl, C3-C6 ring At least one of alkyl, C1-C6 alkoxy or C1-C6 alkylthio.

Preferably, the Ar ³ is biphenyl or phenyl, more preferably phenyl.

Preferably, the X is CR ¹ R ² , NR ³ or SiR ⁴ R ⁵ , more preferably CR ¹ R ² .

Preferably, the R ¹ , R ² , R ³ , R ⁴ , and R ⁵ are each independently selected from substituted or unsubstituted C1-C6 straight chain or branched chain alkyl, substituted or unsubstituted C6-C18 aryl , any of substituted or unsubstituted C3-C18 heteroaryl groups.

Preferably, the R ¹ , R ² , R ³ , R ⁴ , and R ⁵ are each independently methyl or phenyl; the R ¹ and R ² are not connected or connected to form a fluorene ring through a chemical bond, and the R ⁴ and R ⁵ are not connected or connected by a chemical bond to form a ring.

Preferably, the R _f1 , R _f2 , and R _f3 are each independently selected from halogen, cyano, substituted or unsubstituted C1-C6 linear or branched chain alkyl, substituted or unsubstituted C3-C6 cycloalkyl , substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C3-C18 heteroaryl.

Preferably, the k ₁ , k ₂ and k ₃ are all 0.

When there is a substituent group in the "substituted or unsubstituted" mentioned above in this application, all of Ar ¹ , Ar ² , R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R _f1 , R _f2 , and R _f3 The substituting groups are each independently selected from halogen, C1-C10 straight chain or branched chain alkyl, C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, C1-C10 alkoxy, C1-C10 alkylthio , at least one of C6-C30 arylamino, C3-C30 heteroarylamino, C6-C30 aryl or C3-C30 heteroaryl, more preferably halogen, C1-C10 straight chain or branched chain alkyl, At least one of C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, C6-C30 aryl or C3-C30 heteroaryl. The substituent group in Ar ³ is at least one selected from halogen, C1-C6 linear or branched chain alkyl, C3-C6 cycloalkyl, C1-C6 alkoxy or C1-C6 alkylthio.

Preferably, the organic compound has the structure shown in any one of the following P1-P496:

In some embodiments of the present application, when the above-mentioned organic compound is selected from any one or more of the above-mentioned P9, P49, P237, P245, P250, P251, P252, P269, P309, P393 or P394, its application Used as an electron blocking layer material and/or a hole transporting layer material in an organic electroluminescent device, it can more effectively improve the luminous efficiency of the device and reduce the driving voltage.

The second purpose of the present application is to provide an application of the organic compound described in the first purpose, and the organic compound is applied to an organic electroluminescent device.

Preferably, the organic compound acts as an electron blocking material and/or a hole transporting material in an organic electroluminescent device.

In addition to organic electroluminescent devices, the organic compounds of the present application can also be applied to lighting elements, organic thin film transistors, organic field effect transistors, organic thin film solar cells, information labels, electronic artificial skin sheets, sheet type scanners or electronic paper .

The third object of the present application is to provide an organic electroluminescence device, which comprises a first electrode, a second electrode and at least one organic layer arranged between the first electrode and the second electrode ; The organic layer includes at least one organic compound as described in one of the purposes.

Preferably, the organic layer includes an electron blocking layer, and the electron blocking layer includes at least one organic compound as described in one of the purposes.

The organic compound provided by the application is applied to organic electroluminescent devices, and it is used as an electron blocking layer material, especially as a green photoelectron blocking layer material, which can improve the luminous efficiency of the device, reduce the driving voltage, and make the device have better performance.

Preferably, the organic layer includes a hole transport layer, and the hole transport layer includes at least one organic compound as described in one of the purposes.

In a specific technical solution, the organic electroluminescent device (OLED) includes a first electrode and a second electrode, and an organic layer located between the first electrode and the second electrode. The organic layer can be further divided into multiple regions, for example including a hole transport region, a light emitting layer, and an electron transport region.

In particular embodiments, a substrate may be used either below the first electrode or above the second electrode. The substrates are all glass or polymer materials with excellent mechanical strength, thermal stability, water resistance and transparency. In addition, a thin-film transistor (TFT) may be provided on a substrate for a display.

The first electrode may be formed by sputtering or depositing a material used as the first electrode on the substrate. When the first electrode is used as the anode, oxide transparent conductive materials such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO ₂ ), zinc oxide (ZnO) and any combination thereof can be used. When the first electrode is used as the cathode, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In ), magnesium-silver (Mg-Ag) and other metals or alloys and any combination thereof.

The organic layer can be formed on the electrode by vacuum thermal evaporation, spin coating, printing and other methods. Compounds used as organic layers can be small organic molecules, organic macromolecules or polymers, and combinations thereof.

The hole transport region is located between the anode and the light emitting layer. The hole transport region can be a hole transport layer (HTL) with a single-layer structure, including a single-layer hole-transport layer containing only one compound and a single-layer hole-transport layer containing multiple compounds. The hole transport region can also be a multilayer structure comprising at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL); wherein the HIL is positioned between the anode and the HTL, and the EBL It is located between the HTL and the light-emitting layer; the HTL and/or the EBL contain at least one organic compound with the structure of formula I, preferably the EBL contains at least one organic compound with the structure of formula I.

The material of the hole transport region can also be selected from, but not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylene vinylene, polyaniline/dodecylbenzenesulfonic acid ( Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphorsulfonic acid (Pani/CSA), polyaniline/poly (4-styrene sulfonate) (Pani/PSS), aromatic amine derivatives, wherein the aromatic amine derivatives include the following compounds shown in HT-1 to HT-51; or any combination thereof.

A hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material, or a combination of multiple compounds. For example, the hole injection layer can use one or more compounds of the above-mentioned HT-1 to HT-51, or one or more compounds in the following HI-1 to HI-3; HT-1 can also be used One or more compounds to HT-51 are doped with one or more compounds from HI-1 to HI-3 described below.

The luminescent layer includes luminescent dyes (that is, dopant) that can emit different wavelength spectra, and can also include a host material (Host) at the same time. The light-emitting layer may be a monochromatic light-emitting layer that emits a single color such as red, green, or blue. A plurality of monochromatic light emitting layers of different colors can be arranged in a plane according to the pixel pattern, and can also be stacked together to form a colored light emitting layer. When the light-emitting layers of different colors are stacked together, they can be separated from each other or connected to each other. The light-emitting layer can also be a single color light-emitting layer capable of simultaneously emitting different colors such as red, green, and blue.

According to different technologies, different materials such as fluorescent electroluminescent materials, phosphorescent electroluminescent materials, and heat-activated delayed fluorescent luminescent materials can be used as materials for the light-emitting layer. In an OLED device, a single light-emitting technology can be used, or a combination of multiple different light-emitting technologies can be used. These different luminescent materials classified by technology can emit light of the same color or of different colors.

In one aspect of the present application, the light-emitting layer adopts fluorescence electroluminescence technology. The fluorescent host material of the light-emitting layer can be selected from, but not limited to, one or more combinations of BFH-1 to BFH-17 listed below.

In one aspect of the present application, the light-emitting layer adopts fluorescence electroluminescence technology. The fluorescent dopant in the light-emitting layer can be selected from, but not limited to, one or more combinations of BFD-1 to BFD-24 listed below.

In one aspect of the present application, the light-emitting layer adopts phosphorescence electroluminescence technology. The host material of the light-emitting layer is selected from, but not limited to, one or more combinations of PH-1 to PH-85.

In one aspect of the present application, the light-emitting layer adopts phosphorescence electroluminescence technology. The phosphorescent dopant in the light-emitting layer can be selected from, but not limited to, one or more combinations of GPD-1 to GPD-47 listed below.

In one aspect of the present application, the light-emitting layer adopts phosphorescence electroluminescence technology. The phosphorescent dopant in the light-emitting layer can be selected from, but not limited to, one or more combinations of RPD-1 to RPD-28 listed below.

In one aspect of the present application, the light-emitting layer adopts phosphorescence electroluminescence technology. The phosphorescent dopant in the light-emitting layer can be selected from, but not limited to, one or more combinations of YPD-1 to YPD-11 listed below.

The OLED organic layers may also include an electron transport region between the light emitting layer and the cathode. The electron transport region may be a single-layer electron transport layer (ETL), including a single-layer electron-transport layer containing only one compound and a single-layer electron-transport layer containing multiple compounds. The electron transport region may also be a multilayer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

In one aspect of the present application, the electron transport layer material may be selected from, but not limited to, one or more combinations of ET-1 to ET-73 listed below.

In one aspect of the present application, a hole blocking layer (HBL) is located between the electron transport layer and the light emitting layer. Hole blocking layer can adopt, but not limited to, one or more compounds of above-mentioned ET-1 to ET-73, or adopt, but not limited to one or more compounds in PH-1 to PH-46; Mixtures of one or more compounds from ET-1 to ET-73 and one or more compounds from PH-1 to PH-46 are used, but are not limited to.

The device may also include an electron injection layer located between the electron transport layer and the cathode, and the materials of the electron injection layer include but are not limited to one or more combinations of the following: LiQ, LiF, NaCl, CsF, Li ₂ O, Cs ₂ CO ₃ , BaO, Na, Li, Ca, Mg or Yb.

The thicknesses of the above hole injection layer, hole transport layer, electron blocking layer, light emitting layer, hole blocking layer, electron transport layer and electron injection layer are not limited. In order to further improve the luminous efficiency of the light-emitting device and further reduce the driving voltage, the thickness of the hole injection layer is preferably 8 to 12 nm, the thickness of the hole transport layer is preferably 55 to 65 nm, and the thickness of the electron blocking layer is preferably 30 to 40 nm. The thickness of the light-emitting layer is 35-45 nm, the thickness of the hole blocking layer is preferably 3-8 nm, the thickness of the electron transport layer is preferably 20-30 nm, and the thickness of the electron injection layer is preferably 0.8-1.2 nm. Especially when the thickness of the hole injection layer is 10nm, the thickness of the hole transport layer is 60nm, the thickness of the electron blocking layer is 35nm, the thickness of the light-emitting layer is 40nm, the thickness of the hole blocking layer is 5nm, and the thickness of the electron transport layer is When the thickness of the electron injection layer is 25nm and the thickness of the electron injection layer is 1nm, the obtained electroluminescent device has more excellent luminous efficiency and lower driving voltage.

Compared with the prior art, the present application has the following beneficial effects:

The organic compound provided by this application has a structure as shown in formula I. The organic compound has better stability and photoelectric properties through the design of molecular structure, which can improve and balance carrier transport and improve device performance; at the same time, the The molecular weight of the above-mentioned organic compound is suitable, and the evaporation temperature is relatively low, which is beneficial to the industrial production of organic electroluminescent devices. The organic compound is used as an electron blocking layer material of an organic electroluminescent device, which can reduce the driving voltage of the device, improve luminous efficiency, and make the OLED device have better comprehensive performance. At the same time, the preparation method of the organic compound is simple, the raw materials are readily available, and it is easy to realize large-scale mass production.

detailed description

The technical solutions of the present application will be further described below through specific implementation methods. It should be clear to those skilled in the art that the embodiments are only for helping to understand the present application, and should not be regarded as a specific limitation on the present application.

In the present application, the representative synthetic route of the organic compound having the structure shown in formula I is as follows:

Among them, Ar ¹ , Ar ² , Ar ³ , X, R _f1 , R _f2 , R _f3 , k ₁ , k ₂ , and k ₃ have the same meanings as in formula I; Pd(PPh ₃ ) ₄ represents tetrakistriphenyl Palladium phosphine, Pd ₂ (dba) ₃ represents tris(dibenzylacetone) dipalladium (0), Sphos represents 2-bicyclohexylphosphine-2′,6′-dimethoxybiphenyl, IPr.HCl represents 1 , 3-bis(2,6-diisopropylphenyl) imidazolium chloride, NaOBu-t represents sodium tert-butoxide, (t-Bu) ₃ P represents tri-tert-butylphosphine.

The preparation of the organic compound described in the present application includes, but is not limited to, the above-mentioned method. The organic compound represented by formula I synthesized by those skilled in the art by other methods also belongs to the protection scope of the present application.

More specifically, the following synthesis examples in this application exemplarily provide the specific synthesis methods of the organic compounds. The solvents and reagents used in the following synthesis examples can be purchased or customized from the chemical product market. In addition, those skilled in the art can also synthesize by other known methods.

The mass spectrometric characterization data in the following synthesis examples were obtained by testing with a ZAB-HS mass spectrometer manufactured by Micromass, UK.

Synthesis Example 1: Organic Compound P9

In a 1000mL single-necked bottle, add 20.0g of M1, 20.7g of 2-biphenylboronic acid, 1.2g of tetrakistriphenylphosphine palladium Pd(PPh ₃ ) ₄ , 28.9g of potassium carbonate, 300mL of 1,4-dioxane and 100mL of water, vacuumed and changed nitrogen for 3 times, and the reaction temperature was raised to 100°C for 5h. After the reaction is complete, stop the reaction. Cool to room temperature, separate the reaction liquid, purify the organic phase through silica gel column twice, concentrate the organic phase, add methanol to reflux and stir for 1 h, filter with suction to obtain light yellow powder M1-1, and then recrystallize with ethyl acetate to obtain pure product 22.9 g.

M1-1: m/z theoretical value: 309; m/z measured value: 310.

In a 1000mL single-necked bottle, add 22.9g of M1-1, 13.5g of phenylboronic acid, 0.7g of tris(dibenzylacetone)dipalladium(0)Pd ₂ (dba) ₃ , 0.6g of 2-bicyclohexylphosphine-2 ',6'-Dimethoxybiphenyl (Sphos), 31.4g of anhydrous potassium phosphate, 400mL of 1,4-dioxane and 40mL of water, vacuumed and changed nitrogen for 3 times, and the reaction temperature was raised to 100°C for 5h. After the reaction is complete, stop the reaction. Cool to room temperature, separate the reaction liquid, purify the organic phase through silica gel column twice, concentrate the organic phase, add methanol to reflux and stir for 1 h, filter with suction to obtain light yellow powder M1-2, and then recrystallize with ethyl acetate to obtain pure product 16.9 g.

M1-2: m/z theoretical value: 351; m/z measured value: 352.

In a 1000mL single-necked bottle, add 16.9g of M1-2, 2mL of hydrazine hydrate, 0.5g of palladium carbon (Pd/C) and 300mL of ethanol, vacuum and change nitrogen for 3 times, and the reaction temperature is raised to 90°C for 5h. After the reaction is complete, stop the reaction. Cool to room temperature, separate the reaction liquid, purify the organic phase through silica gel column twice, concentrate the organic phase, add methanol to reflux and stir for 1 h, filter with suction to obtain white powder M1-3, and then recrystallize with ethyl acetate to obtain 14.5 g of pure product .

M1-3: m/z theoretical value: 321; m/z measured value: 322.

In a 1000mL single-necked bottle, add 14.5g of M1-3, 12.3g of 2-bromo-9,9-dimethylfluorene, 0.4g of Pd ₂ (dba) ₃ , 0.4g of 1,3-bis(2 , 6-diisopropylphenyl)imidazolium chloride (IPr.HCl), 13.0g sodium tert-butoxide NaOBu-t, 300mL toluene, vacuum and change nitrogen 3 times, and the reaction temperature was raised to 90°C for 5h. After the reaction is complete, stop the reaction. Cool to room temperature, separate the reaction solution, purify the organic phase through silica gel column twice, concentrate the organic phase, add methanol to reflux and stir for 1 h, filter with suction to obtain light yellow powder M1-4, and then recrystallize with ethyl acetate to obtain pure product 17.1 g.

M1-4: m/z theoretical value: 513; m/z measured value: 514.

In a 1000 mL single-necked bottle, add 17.1 g of M1-4, 7.7 g of 4-bromobiphenyl, 0.3 g of Pd ₂ (dba) ₃ , 0.4 mL of tert-butylphosphine (t-Bu) ₃ P, 9.6 g of t- Sodium butoxide and 300mL of toluene were vacuumed and replaced with nitrogen three times, and the reaction temperature was raised to 110°C for 5 hours. After the reaction is complete, stop the reaction. Cool to room temperature, separate the reaction liquid, purify the organic phase through silica gel column twice, concentrate the organic phase, add methanol to reflux and stir for 1 h, filter with suction to obtain light yellow powder P9, and then recrystallize three times from ethyl acetate to obtain 8.5 g of pure product .

Organic compound P9: m/z theoretical: 665; m/z found: 666.

Synthesis Example 2-11

The process routes of Synthesis Examples 2-11 are the same as those of Synthesis Example 1, except that the raw materials are different. The raw materials, target products and characterization data of the results are shown in Table 1.

Table 1

Example 1

A kind of organic electroluminescence device, comprises anode (ITO), hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer and negative electrode (Al ).

The preparation method of the organic electroluminescent device is as follows: the glass plate coated with the ITO transparent conductive layer is ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, and ultrasonically degreased in a mixed solvent of acetone/ethanol. Baking in a clean environment until moisture is completely removed, cleaning with ultraviolet light and ozone, and bombarding the surface with a low-energy positive ion beam; placing the above-mentioned glass substrate with an anode in a vacuum chamber, and evacuating to <1×10 ^-5 Pa, On the above-mentioned anode layer film, 10nm compound HT-4: HI-3 (97/3, w/w) mixture was vacuum thermally evaporated sequentially as the hole injection layer, and 60nm compound HT-4 was used as the hole transport layer , 35nm of the organic compound P9 provided by the application as an electron blocking layer; 40nm of the compound PH-61:PH-3:GPD-12 (100:100:20, w/w) ternary mixture as the light-emitting layer; 5nm of ET -23 as hole blocking layer, 25nm compound ET-69:ET-57 (50/50, w/w) mixture as electron transport layer, 1nm LiF as electron injection layer, 150nm metal aluminum as cathode; all organic The total evaporation rate of layer and LiF is controlled at 0.1nm/s, and the evaporation rate of metal electrode is controlled at 1nm/s.

Example 2-11

An organic electroluminescent device, the only difference from Example 1 is that the electronic blocking layer material organic compound P9 is replaced by P49, P237, P245, P250, P251, P252, P269, P309, P393, P394.

Comparative example 1-5

An organic electroluminescent device, the only difference from Example 1 is that the electron blocking layer material organic compound P9 is replaced by CCP-1, CCP-2, CCP-3, CCP-4, CCP-5.

The following performance tests were performed on the organic electroluminescent devices provided in Examples 1-11 and Comparative Examples 1-5: Under the same brightness, the driving voltage and current efficiency of the organic electroluminescent devices were measured using a digital source meter and a luminance meter. Specifically, increase the voltage at a rate of 0.1V per ^second , measure the voltage when the brightness of the organic electroluminescent device reaches 10000cd/m2, that is, the driving voltage, and measure the current density at this time; the ratio of brightness to current density That is the current efficiency; the test results are shown in Table 2.

Table 2

According to the results in Table 2, it can be seen that the organic compound provided by the present application is applied to an organic electroluminescent device, which can make the driving voltage of the device under the brightness of 10000cd/m ² be 4.0-4.2V, and the current efficiency is 66.4-68.1cd/A, Therefore, the driving voltage can be effectively reduced, the current efficiency can be improved, and it is a green photoelectron blocking layer material with good performance.

The difference between the electron blocking layer material CCP-1 in Comparative Example 1 and P237 in Example 2 is that the fluorenyl group in CCP-1 is connected to the N atom through a phenylene group, which reduces the mobility of CCP-1. The molecular packing density is poor, which affects the luminous efficiency and driving voltage of the device; in the electron blocking layer materials in Comparative Examples 2-4, the N atoms of the arylamine are connected to the 1-position, 3-position, and 4-position of the fluorenyl group respectively , compared with the 2-position where the N atom is connected to the fluorenyl group, the mobility is lower, which is not conducive to the transmission of excitons, so the device performance is poor; the N-ortho position of the arylamine in Comparative Example 5 has no substituents connected, so that the molecular The LUMO energy level is deep, which reduces the luminescent performance of the device.

The applicant declares that the application uses the above examples to illustrate an organic compound of the application and its application, but the application is not limited to the above examples, that is, it does not mean that the application must rely on the above examples to be implemented. Those skilled in the art should understand that any improvement to the present application, the equivalent replacement of each raw material of the product of the present application, the addition of auxiliary components, the selection of specific methods, etc., all fall within the scope of protection and disclosure of the present application.

Claims (11)

An organic compound, characterized in that the organic compound has a structure as shown in formula I:

Wherein, Ar ¹ and Ar ² are each independently selected from any one of substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; Ar ³ is selected from any one of substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted C3-C11 heteroaryl; X is selected from any one of O, S, CR ¹ R ² , NR ³ or SiR ⁴ R ⁵ ; R ¹ , R ² , R ³ , R ⁴ , and R ⁵ are each independently selected from hydrogen, substituted or unsubstituted C1-C20 linear or branched chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted Or any of unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; R ¹ and R ² are not connected or are connected to form a ring by a chemical bond, R ⁴ and R ⁵ are not connected or are connected to form a ring by a chemical bond; R _f1 , R _f2 , and R _f3 are each independently selected from halogen, cyano, substituted or unsubstituted C1-C20 linear or branched chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted Any one of C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; Ar ¹ , Ar ² , R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R _f1 , R _f2 , and R _f3 are each independently selected from halogen, C1-C10 straight chain or branched Alkanyl, C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, C1-C10 alkoxy, C1-C10 alkylthio, C6-C30 arylamino, C3-C30 heteroarylamino, C6- At least one of C30 aryl or C3-C30 heteroaryl; The substituted substituent in Ar ³ is selected from at least one of halogen, C1-C6 linear or branched chain alkyl, C3-C6 cycloalkyl, C1-C6 alkoxy or C1-C6 alkylthio; k ₁ and k ₂ are each independently an integer of 0-3; k ₃ is an integer of 0-4. The organic compound according to claim 1, wherein said Ar ¹ and Ar ² are each independently selected from substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C10-C20 fused ring heteroaryl any of the Preferably, the Ar ¹ and Ar ² are each independently selected from any of the following substituted or unsubstituted groups:

Wherein, * represents the connection site of the group; Z is selected from any one of O, S, CR ¹¹ R ¹² , NR ¹³ or SiR ¹⁴ R ¹⁵ ; R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ are each independently selected from hydrogen, substituted or unsubstituted C1-C20 linear or branched chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted Or any of unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; R ¹¹ and R ¹² are not connected or are connected to form a ring through a chemical bond, R ¹⁴ and R ¹⁵ are not connected or are connected to form a ring through a chemical bond; Preferably, the R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ are each independently methyl or phenyl; R ¹¹ and R ¹² are not connected or connected to form a ring through a chemical bond, and R ¹⁴ and R ¹⁵ are not connected Or connect to form a ring by chemical bonds. The organic compound according to claim ¹ or 2, wherein the Ar is selected from any one of substituted or unsubstituted following groups:

Wherein, * represents the connection site of the group; Preferably, the Ar is selected from any one of the following substituted or unsubstituted groups ^:

Among them, * represents the linking site of the group. The organic compound according to claim 1, characterized in that, the Ar ¹ and Ar ² are not simultaneously phenyl groups. The organic compound according to claim ¹ , wherein the Ar is substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, and the substituted substituent is selected from halogen, C1-C6 straight At least one of chain or branched alkyl, C3-C6 cycloalkyl, C1-C6 alkoxy or C1-C6 alkylthio; Preferably, the Ar ³ is phenyl. The organic compound according to claim 1, wherein the X is CR ¹ R ² , NR ³ or SiR ⁴ R ⁵ , preferably CR ¹ R ² ; Preferably, the R ¹ , R ² , R ³ , R ⁴ , and R ⁵ are each independently selected from substituted or unsubstituted C1-C6 straight chain or branched chain alkyl, substituted or unsubstituted C6-C18 aryl , any of substituted or unsubstituted C3-C18 heteroaryl; Preferably, the R ¹ , R ² , R ³ , R ⁴ , and R ⁵ are each independently methyl or phenyl; the R ¹ and R ² are not connected or connected to form a fluorene ring through a chemical bond, and the R ⁴ and R ⁵ are not connected or connected by a chemical bond to form a ring. The compound according to claim 1, wherein each of said R _f1 , R _f2 , and R _f3 is independently selected from halogen, cyano, substituted or unsubstituted C1-C6 straight or branched chain alkyl, substituted Or any of unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C3-C18 heteroaryl; Preferably, the k ₁ , k ₂ and k ₃ are all 0. The organic compound according to claim 1, wherein the organic compound has a structure shown in any one of the following P1-P496:

The organic compound according to claim 8, wherein the organic compound is selected from at least one of P9, P49, P237, P245, P250, P251, P252, P269, P309, P393 or P394. A kind of application of the organic compound as described in any one in claim 1-9, it is characterized in that, described organic compound is applied to organic electroluminescence device, illuminating element, organic thin film transistor, organic field effect transistor, organic thin film Solar cells, information labels, electronic artificial skin sheets, sheet-type scanners or electronic paper; Preferably, the organic compound acts as an electron blocking material and/or a hole transporting material in an organic electroluminescent device. An organic electroluminescent device, characterized in that the organic electroluminescent device comprises a first electrode, a second electrode and at least one organic layer arranged between the first electrode and the second electrode; the organic The layer comprises at least one organic compound according to any one of claims 1-9; Preferably, the organic layer includes an electron blocking layer, and the electron blocking layer includes at least one organic compound according to any one of claims 1-9; Preferably, the organic layer includes a hole transport layer, and the hole transport layer includes at least one organic compound according to any one of claims 1-9.