Patent Application
20240376088
This application claims priority to Chinese Patent Application No. 202310070285.5 filed on Jan. 13, 2023, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to compounds for organic electronic devices such as organic light-emitting devices. In particular, the present disclosure relates to a compound having a structure of Formula 1, an organic electroluminescent device including the compound and a compound composition including the compound.
Organic electronic devices include, but are not limited to, the following types: organic light-emitting diodes (OLEDs), organic field-effect transistors (O-FETs), organic light-emitting transistors (OLETs), organic photovoltaic devices (OPVs), dye-sensitized solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field-quench devices (OFQDs), light-emitting electrochemical cells (LECs), organic laser diodes and organic plasmon emitting devices.
In 1987, Tang and Van Slyke of Eastman Kodak reported a bilayer organic electroluminescent device, which comprises an arylamine hole transporting layer and a tris-8-hydroxyquinolato-aluminum layer as the electron and emitting layer (Applied Physics Letters, 1987, 51 (12): 913-915). Once a bias is applied to the device, green light was emitted from the device. This device laid the foundation for the development of modem organic light-emitting diodes (OLEDs). State-of-the-art OLEDs may comprise multiple layers such as charge injection and transporting layers, charge and exciton blocking layers, and one or multiple emissive layers between the cathode and anode. Since the OLED is a self-emitting solid state device, it offers tremendous potential for display and lighting applications. In addition, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications such as fabrication on flexible substrates.
The OLED can be categorized as three different types according to its emitting mechanism. The OLED invented by Tang and van Slyke is a fluorescent OLED. It only utilizes singlet emission. The triplets generated in the device are wasted through nonradiative decay channels. Therefore, the internal quantum efficiency (IQE) of the fluorescent OLED is only 25%. This limitation hindered the commercialization of OLED. In 1997, Forrest and Thompson reported phosphorescent OLED, which uses triplet emission from heavy metal containing complexes as the emitter. As a result, both singlet and triplets can be harvested, achieving 100% IQE. The discovery and development of phosphorescent OLED contributed directly to the commercialization of active-matrix OLED (AMOLED) due to its high efficiency. Recently, Adachi achieved high efficiency through thermally activated delayed fluorescence (TADF) of organic compounds. These emitters have small singlet-triplet gap that makes the transition from triplet back to singlet possible. In the TADF device, the triplet excitons can go through reverse intersystem crossing to generate singlet excitons, resulting in high IQE.
OLEDs can also be classified as small molecule and polymer OLEDs according to the forms of the materials used. A small molecule refers to any organic or organometallic material that is not a polymer. The molecular weight of the small molecule can be large as long as it has well defined structure. Dendrimers with well-defined structures are considered as small molecules. Polymer OLEDs include conjugated polymers and non-conjugated polymers with pendant emitting groups. Small molecule OLED can become the polymer OLED if post polymerization occurred during the fabrication process.
There are various methods for OLED fabrication. Small molecule OLEDs are generally fabricated by vacuum thermal evaporation. Polymer OLEDs are fabricated by solution process such as spin-coating, inkjet printing, and slit printing. If the material can be dissolved or dispersed in a solvent, the small molecule OLED can also be produced by solution process.
The emitting color of the OLED can be achieved by emitter structural design. An OLED may comprise one emitting layer or a plurality of emitting layers to achieve desired spectrum. In the case of green, yellow, and red OLEDs, phosphorescent emitters have successfully reached commercialization. Blue phosphorescent device still suffers from non-saturated blue color, short device lifetime, and high operating voltage. Commercial full-color OLED displays normally adopt a hybrid strategy, using fluorescent blue and phosphorescent yellow, or red and green. At present, efficiency roll-off of phosphorescent OLEDs at high brightness remains a problem. In addition, it is desirable to have more saturated emitting color, higher efficiency, and longer device lifetime.
Triazine-based organic semiconductor materials have been widely used in OLEDs due to their superior photoelectric performance, redox performance and stability.
US20190214570A1 discloses an organic compound having a structure of the following formula and an organic light-emitting device including the compound:
wherein Ar1 is selected from
and Ar2 is selected from
wherein E1 is selected from C(R21)(R22), Si(R23)(R24), N(R25), O or S. It can be seen that when E1 is selected from S, triazine is only joined to a fixed 1-position of the structure
through a single bond or a linking group, for example, the specific compound
disclosed in this application. Therefore, it can be seen that this application does not disclose or teach a compound where triazine is joined to other positions of dibenzothiophene through a single bond or a linking group and the use thereof in organic electroluminescent devices.
However, currently reported triazine-based organic semiconductor materials have certain limitations in terms of carrier transporting ability and lifetime in optoelectronic devices. Therefore, the application potential of such materials is worthy of further research and development.
The present disclosure aims to provide a series of compounds each having a structure of Formula 1 to solve at least part of the above-mentioned problems. These compounds can be applied to organic electroluminescent devices and can significantly improve the overall performance of the device, for example, a low drive voltage, high device efficiency and a significantly improved device lifetime.
According to an embodiment of the present disclosure, a compound having a structure of Formula 1 is disclosed:
shown in Formula 1;
According to an embodiment of the present disclosure, an organic electroluminescent device is further disclosed. The organic electroluminescent device includes an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer includes the compound of Formula 1 described in the preceding embodiment.
According to another embodiment of the present disclosure, a compound composition is further disclosed. The compound composition includes the compound of Formula 1 described in the preceding embodiment.
The present disclosure discloses a series of compounds each having a structure of Formula 1. These compounds can be used as a host material, an electron transporting material or a hole blocking material in the organic electroluminescent device and can significantly improve the overall performance of the device, for example, a low drive voltage, high device efficiency and a significantly improved device lifetime.
OLEDs can be fabricated on various types of substrates such as glass, plastic, and metal foil.
More examples for each of these layers are available. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference herein in its entirety. An example of a p-doped hole transporting layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference herein in its entirety. Examples of host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al., which is incorporated by reference herein in its entirety. An example of an n-doped electron transporting layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference herein in its entirety. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference herein in their entireties, disclose examples of cathodes including composite cathodes having a thin layer of metal such as Mg:Ag with an overlying transparent, electrically-conductive, sputter-deposited ITO layer. The theory and use of blocking layers are described in more detail in U.S. Pat. No. 6,097,147 and U.S. Patent Application Publication No. 2003/0230980, which are incorporated by reference herein in their entireties. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference herein in its entirety. A description of protective layers may be found in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference herein in its entirety.
The layered structure described above is provided by way of non-limiting examples. Functional OLEDs may be achieved by combining the various layers described in different ways, or layers may be omitted entirely. It may also include other layers not specifically described. Within each layer, a single material or a mixture of multiple materials can be used to achieve optimum performance. Any functional layer may include several sublayers. For example, the emissive layer may have two layers of different emitting materials to achieve desired emission spectrum.
In one embodiment, an OLED may be described as having an “organic layer” disposed between a cathode and an anode. This organic layer may include a single layer or multiple layers.
An OLED can be encapsulated by a barrier layer.
Devices fabricated in accordance with embodiments of the present disclosure can be incorporated into a wide variety of consumer products that have one or more of the electronic component modules (or units) incorporated therein. Some examples of such consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads-up displays, fully or partially transparent displays, flexible displays, smart phones, tablets, phablets, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicles displays, and vehicle tail lights.
The materials and structures described herein may be used in other organic electronic devices listed above.
As used herein, “top” means furthest away from the substrate, while “bottom” means closest to the substrate. Where a first layer is described as “disposed over” a second layer, the first layer is disposed further away from the substrate. There may be other layers between the first and second layers, unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “disposed over” an anode, even though there are various organic layers in between.
As used herein, “solution processible” means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium, either in solution or suspension form.
A ligand may be referred to as “photoactive” when it is believed that the ligand directly contributes to the photoactive properties of an emissive material. A ligand may be referred to as “ancillary” when it is believed that the ligand does not contribute to the photoactive properties of an emissive material, although an ancillary ligand may alter the properties of a photoactive ligand.
It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin statistics limit through delayed fluorescence. As used herein, there are two types of delayed fluorescence, i.e. P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated from triplet-triplet annihilation (TTA).
On the other hand, E-type delayed fluorescence does not rely on the collision of two triplets, but rather on the transition between the triplet states and the singlet excited states. Compounds that are capable of generating E-type delayed fluorescence are required to have very small singlet-triplet gaps to convert between energy states. Thermal energy can activate the transition from the triplet state back to the singlet state. This type of delayed fluorescence is also known as thermally activated delayed fluorescence (TADF). A distinctive feature of TADF is that the delayed component increases as temperature rises. If the reverse intersystem crossing (RISC) rate is fast enough to minimize the non-radiative decay from the triplet state, the fraction of back populated singlet excited states can potentially reach 75%. The total singlet fraction can be 100%, far exceeding 25% of the spin statistics limit for electrically generated excitons.
E-type delayed fluorescence characteristics can be found in an exciplex system or in a single compound. Without being bound by theory, it is believed that E-type delayed fluorescence requires the luminescent material to have a small singlet-triplet energy gap (ΔES-T). Organic, non-metal containing, donor-acceptor luminescent materials may be able to achieve this. The emission in these materials is generally characterized as a donor-acceptor charge-transfer (CT) type emission. The spatial separation of the HOMO and LUMO in these donor-acceptor type compounds generally results in small ΔES-T. These states may involve CT states. Generally, donor-acceptor luminescent materials are constructed by connecting an electron donor moiety such as amino- or carbazole-derivatives and an electron acceptor moiety such as N-containing six-membered aromatic rings.
Halogen or halide—as used herein includes fluorine, chlorine, bromine, and iodine.
Alkyl—as used herein includes both straight and branched chain alkyl groups. Alkyl may be alkyl having 1 to 20 carbon atoms, preferably alkyl having 1 to 12 carbon atoms, and more preferably alkyl having 1 to 6 carbon atoms. Examples of alkyl groups include a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an s-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, a neopentyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 1-pentylhexyl group, a 1-butylpentyl group, a 1-heptyloctyl group, and a 3-methylpentyl group. Of the above, preferred are a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an s-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, a neopentyl group, and an n-hexyl group. Additionally, the alkyl group may be optionally substituted.
Cycloalkyl—as used herein includes cyclic alkyl groups. The cycloalkyl groups may be those having 3 to 20 ring carbon atoms, preferably those having 4 to 10 carbon atoms. Examples of cycloalkyl include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcylcohexyl, 1-adamantyl, 2-adamantyl, 1-norbomyl, 2-norbomyl, and the like. Of the above, preferred are cyclopentyl, cyclohexyl, 4-methylcyclohexyl, and 4,4-dimethylcylcohexyl. Additionally, the cycloalkyl group may be optionally substituted.
Heteroalkyl—as used herein, includes a group formed by replacing one or more carbons in an alkyl chain with a hetero-atom(s) selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, a phosphorus atom, a silicon atom, a germanium atom, and a boron atom. Heteroalkyl may be those having 1 to 20 carbon atoms, preferably those having 1 to 10 carbon atoms, and more preferably those having 1 to 6 carbon atoms. Examples of heteroalkyl include methoxymethyl, ethoxymethyl, ethoxyethyl, methylthiomethyl, ethylthiomethyl, ethylthioethyl, methoxymethoxymethyl, ethoxymethoxymethyl, ethoxyethoxyethyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, mercaptomethyl, mercaptoethyl, mercaptopropyl, aminomethyl, aminoethyl, aminopropyl, dimethylaminomethyl, trimethylgermanylmethyl, trimethylgermanylethyl, trimethylgermanylisopropyl, dimethylethylgermanylmethyl, dimethylisopropylgermanylmethyl, tert-butyldimethylgermanylmethyl, triethylgermanylmethyl, triethylgermanylethyl, triisopropylgermanylmethyl, triisopropylgermanylethyl, trimethylsilylmethyl, trimethylsilylethyl, trimethylsilylisopropyl, triisopropylsilylmethyl, and triisopropylsilylethyl. Additionally, the heteroalkyl group may be optionally substituted.
Alkenyl—as used herein includes straight chain, branched chain, and cyclic alkene groups. Alkenyl may be those having 2 to 20 carbon atoms, preferably those having 2 to 10 carbon atoms. Examples of alkenyl include vinyl, 1-propenyl group, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butandienyl, 1-methylvinyl, styryl, 2,2-diphenylvinyl, 1,2-diphenylvinyl, 1-methylallyl, 1,1-dimethylallyl, 2-methylallyl, 1-phenylallyl, 2-phenylallyl, 3-phenylallyl, 3,3-diphenylallyl, 1,2-dimethylallyl, 1-phenyl-1-butenyl, 3-phenyl-1-butenyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, cycloheptenyl, cycloheptatrienyl, cyclooctenyl, cyclooctatetraenyl, and norbornenyl. Additionally, the alkenyl group may be optionally substituted.
Alkynyl—as used herein includes straight chain alkynyl groups. Alkynyl may be those having 2 to 20 carbon atoms, preferably those having 2 to 10 carbon atoms. Examples of alkynyl groups include ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3,3-dimethyl-1-butynyl, 3-ethyl-3-methyl-1-pentynyl, 3,3-diisopropyl-1-pentynyl, phenylethynyl, phenylpropynyl, etc. Of the above, preferred are ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, and phenylethynyl. Additionally, the alkynyl group may be optionally substituted.
Aryl or an aromatic group—as used herein includes non-condensed and condensed systems. Aryl may be those having 6 to 30 carbon atoms, preferably those having 6 to 20 carbon atoms, and more preferably those having 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene, and naphthalene. Examples of non-condensed aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4′-methylbiphenylyl, 4″-t-butyl-p-terphenyl-4-yl, o-cumenyl, m-cumenyl, p-cumenyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl, and m-quarterphenyl. Additionally, the aryl group may be optionally substituted.
Heterocyclic groups or heterocycle—as used herein include non-aromatic cyclic groups. Non-aromatic heterocyclic groups include saturated heterocyclic groups having 3 to 20 ring atoms and unsaturated non-aromatic heterocyclic groups having 3 to 20 ring atoms, where at least one ring atom is selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, a silicon atom, a phosphorus atom, a germanium atom, and a boron atom. Preferred non-aromatic heterocyclic groups are those having 3 to 7 ring atoms, each of which includes at least one hetero-atom such as nitrogen, oxygen, silicon, or sulfur. Examples of non-aromatic heterocyclic groups include oxiranyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, dioxolanyl, dioxanyl, aziridinyl, dihydropyrrolyl, tetrahydropyrrolyl, piperidinyl, oxazolidinyl, morpholinyl, piperazinyl, oxepinyl, thiepinyl, azepinyl, and tetrahydrosilolyl. Additionally, the heterocyclic group may be optionally substituted.
Heteroaryl—as used herein, includes non-condensed and condensed hetero-aromatic groups having 1 to 5 hetero-atoms, where at least one hetero-atom is selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, a silicon atom, a phosphorus atom, a germanium atom, and a boron atom. A hetero-aromatic group is also referred to as heteroaryl. Heteroaryl may be those having 3 to 30 carbon atoms, preferably those having 3 to 20 carbon atoms, and more preferably those having 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridoindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborine, 1,3-azaborine, 1,4-azaborine, borazine, and aza-analogs thereof. Additionally, the heteroaryl group may be optionally substituted.
Alkoxy—as used herein, is represented by —O-alkyl, —O-cycloalkyl, —O-heteroalkyl, or —O-heterocyclic group. Examples and preferred examples of alkyl, cycloalkyl, heteroalkyl, and heterocyclic groups are the same as those described above. Alkoxy groups may be those having 1 to 20 carbon atoms, preferably those having 1 to 6 carbon atoms. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, methoxypropyloxy, ethoxyethyloxy, methoxymethyloxy, and ethoxymethyloxy. Additionally, the alkoxy group may be optionally substituted.
Aryloxy—as used herein, is represented by —O-aryl or —O-heteroaryl. Examples and preferred examples of aryl and heteroaryl are the same as those described above. Aryloxy groups may be those having 6 to 30 carbon atoms, preferably those having 6 to 20 carbon atoms. Examples of aryloxy groups include phenoxy and biphenyloxy. Additionally, the aryloxy group may be optionally substituted.
Arylalkyl—as used herein, contemplates alkyl substituted with an aryl group. Arylalkyl may be those having 7 to 30 carbon atoms, preferably those having 7 to 20 carbon atoms, and more preferably those having 7 to 13 carbon atoms. Examples of arylalkyl groups include benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl-t-butyl, alpha-naphthylmethyl, 1-alpha-naphthylethyl, 2-alpha-naphthylethyl, 1-alpha-naphthylisopropyl, 2-alpha-naphthylisopropyl, beta-naphthylmethyl, 1-beta-naphthylethyl, 2-beta-naphthylethyl, 1-beta-naphthylisopropyl, 2-beta-naphthylisopropyl, p-methylbenzyl, m-methylbenzyl, o-methylbenzyl, p-chlorobenzyl, m-chlorobenzyl, o-chlorobenzyl, p-bromobenzyl, m-bromobenzyl, o-bromobenzyl, p-iodobenzyl, m-iodobenzyl, o-iodobenzyl, p-hydroxybenzyl, m-hydroxybenzyl, o-hydroxybenzyl, p-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-hydroxy-2-phenylisopropyl, and 1-chloro-2-phenylisopropyl. Of the above, preferred are benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, and 2-phenylisopropyl. Additionally, the arylalkyl group may be optionally substituted.
Alkylsilyl—as used herein, contemplates a silyl group substituted with an alkyl group. Alkylsilyl groups may be those having 3 to 20 carbon atoms, preferably those having 3 to 10 carbon atoms. Examples of alkylsilyl groups include trimethylsilyl, triethylsilyl, methyldiethylsilyl, ethyldimethylsilyl, tripropylsilyl, tributylsilyl, triisopropylsilyl, methyldiisopropylsilyl, dimethylisopropylsilyl, tri-t-butylsilyl, triisobutylsilyl, dimethyl t-butylsilyl, and methyldi-t-butylsilyl. Additionally, the alkylsilyl group may be optionally substituted.
Arylsilyl—as used herein, contemplates a silyl group substituted with an aryl group. Arylsilyl groups may be those having 6 to 30 carbon atoms, preferably those having 8 to 20 carbon atoms. Examples of arylsilyl groups include triphenylsilyl, phenyldibiphenylylsilyl, diphenylbiphenylsilyl, phenyldiethylsilyl, diphenylethylsilyl, phenyldimethylsilyl, diphenylmethylsilyl, phenyldiisopropylsilyl, diphenylisopropylsilyl, diphenylbutylsilyl, diphenylisobutylsilyl, diphenyl t-butylsilyl. Additionally, the arylsilyl group may be optionally substituted.
Alkylgermanyl—as used herein contemplates a germanyl substituted with an alkyl group. The alkylgermanyl may be those having 3 to 20 carbon atoms, preferably those having 3 to 10 carbon atoms. Examples of alkylgermanyl include trimethylgermanyl, triethylgermanyl, methyldiethylgermanyl, ethyldimethylgermanyl, tripropylgermanyl, tributylgermanyl, triisopropylgermanyl, methyldiisopropylgermanyl, dimethylisopropylgermanyl, tri-t-butylgermanyl, triisobutylgermanyl, dimethyl-t-butylgermanyl, and methyldi-t-butylgermanyl. Additionally, the alkylgermanyl may be optionally substituted.
Arylgermanyl—as used herein contemplates a germanyl substituted with at least one aryl group or heteroaryl group. Arylgermanyl may be those having 6 to 30 carbon atoms, preferably those having 8 to 20 carbon atoms. Examples of arylgermanyl include triphenylgermanyl, phenyldibiphenylylgermanyl, diphenylbiphenylgermanyl, phenyldiethylgermanyl, diphenylethylgermanyl, phenyldimethylgermanyl, diphenylmethylgermanyl, phenyldiisopropylgermanyl, diphenylisopropylgermanyl, diphenylbutylgermanyl, diphenylisobutylgermanyl, and diphenyl-t-butylgermanyl. Additionally, the arylgermanyl may be optionally substituted.
The term “aza” in azadibenzofuran, azadibenzothiophene, etc. means that one or more of C—H groups in the respective aromatic fragment are replaced by a nitrogen atom. For example, azatriphenylene encompasses dibenzo[f,h]quinoxaline, dibenzo[f,h]quinoline and other analogs with two or more nitrogens in the ring system. One of ordinary skill in the art can readily envision other nitrogen analogs of the aza-derivatives described above, and all such analogs are intended to be encompassed by the terms as set forth herein.
In the present disclosure, unless otherwise defined, when any term of the group consisting of substituted alkyl, substituted cycloalkyl, substituted heteroalkyl, substituted heterocyclic group, substituted arylalkyl, substituted alkoxy, substituted aryloxy, substituted alkenyl, substituted alkynyl, substituted aryl, substituted heteroaryl, substituted alkylsilyl, substituted arylsilyl, substituted alkylgermanyl, substituted arylgermanyl, substituted amino, substituted acyl, substituted carbonyl, a substituted carboxylic acid group, a substituted ester group, substituted sulfinyl, substituted sulfonyl, and substituted phosphino is used, it means that any group of alkyl, cycloalkyl, heteroalkyl, heterocyclic group, arylalkyl, alkoxy, aryloxy, alkenyl, alkynyl, aryl, heteroaryl, alkylsilyl, arylsilyl, alkylgermanyl, arylgermanyl, amino, acyl, carbonyl, a carboxylic acid group, an ester group, sulfinyl, sulfonyl, and phosphino may be substituted with one or more groups selected from the group consisting of deuterium, halogen, unsubstituted alkyl having 1 to 20 carbon atoms, unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, unsubstituted heteroalkyl having 1 to 20 carbon atoms, an unsubstituted heterocyclic group having 3 to 20 ring atoms, unsubstituted arylalkyl having 7 to 30 carbon atoms, unsubstituted alkoxy having 1 to 20 carbon atoms, unsubstituted aryloxy having 6 to 30 carbon atoms, unsubstituted alkenyl having 2 to 20 carbon atoms, unsubstituted alkynyl having 2 to 20 carbon atoms, unsubstituted aryl having 6 to 30 carbon atoms, unsubstituted heteroaryl having 3 to 30 carbon atoms, unsubstituted alkylsilyl having 3 to 20 carbon atoms, unsubstituted arylsilyl group having 6 to 20 carbon atoms, unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, unsubstituted arylgermanyl group having 6 to 20 carbon atoms, unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.
It is to be understood that when a molecular fragment is described as being a substituent or otherwise attached to another moiety, its name may be written as if it were a fragment (e.g. phenyl, phenylene, naphthyl, dibenzofuranyl) or as if it were the whole molecule (e.g. benzene, naphthalene, dibenzofuran). As used herein, these different ways of designating a substituent or an attached fragment are considered to be equivalent.
In the compounds mentioned in the present disclosure, hydrogen atoms may be partially or fully replaced by deuterium. Other atoms such as carbon and nitrogen may also be replaced by their other stable isotopes. The replacement by other stable isotopes in the compounds may be preferred due to its enhancements of device efficiency and stability.
In the compounds mentioned in the present disclosure, multiple substitutions refer to a range that includes di-substitutions, up to the maximum available substitutions. When substitution in the compounds mentioned in the present disclosure represents multiple substitutions (including di-, tri-, and tetra-substitutions etc.), that means the substituent may exist at a plurality of available substitution positions on its linking structure, the substituents present at a plurality of available substitution positions may have the same structure or different structures.
In the compounds mentioned in the present disclosure, adjacent substituents in the compounds cannot be joined to form a ring unless otherwise explicitly defined, for example, adjacent substituents can be optionally joined to form a ring. In the compounds mentioned in the present disclosure, the expression that adjacent substituents can be optionally joined to form a ring includes a case where adjacent substituents may be joined to form a ring and a case where adjacent substituents are not joined to form a ring. When adjacent substituents can be optionally joined to form a ring, the ring formed may be monocyclic or polycyclic (including spirocyclic, endocyclic, fusedcyclic, and etc.), as well as alicyclic, heteroalicyclic, aromatic, or heteroaromatic. In such expression, adjacent substituents may refer to substituents bonded to the same atom, substituents bonded to carbon atoms which are directly bonded to each other, or substituents bonded to carbon atoms which are more distant from each other. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom and substituents bonded to carbon atoms which are directly bonded to each other.
The expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that two substituents bonded to the same carbon atom are joined to each other via a chemical bond to form a ring, which can be exemplified by the following formula:
The expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that two substituents bonded to carbon atoms which are directly bonded to each other are joined to each other via a chemical bond to form a ring, which can be exemplified by the following formula:
The expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that two substituents bonded to further distant carbon atoms are joined to each other via a chemical bond to form a ring, which can be exemplified by the following formula:
Furthermore, the expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that, in the case where one of the two substituents bonded to carbon atoms which are directly bonded to each other represents hydrogen, the second substituent is bonded at a position at which the hydrogen atom is bonded, thereby forming a ring. This is exemplified by the following formula:
According to an embodiment of the present disclosure, a compound having a structure of Formula 1 is disclosed:
shown in Formula 1;
Herein, the expression that “adjacent substituents Rx can be optionally joined to form a ring” is intended to mean that any two adjacent substituents Rx can be joined to form a ring. Obviously, it is possible that any adjacent substituents Rx are not joined to form a ring.
Herein, the expression that “adjacent substituents Ry can be optionally joined to form a ring” is intended to mean that any two adjacent substituents Ry can be joined to form a ring. Obviously, it is possible that any adjacent substituents Ry are not joined to form a ring.
Herein, the expression that “adjacent substituents Rz can be optionally joined to form a ring” is intended to mean that any two adjacent substituents Rz can be joined to form a ring. Obviously, it is possible that any adjacent Rz are not joined to form a ring.
Herein, the expression that “adjacent substituents Rv can be optionally joined to form a ring” is intended to mean that any two adjacent substituents Rv can be joined to form a ring. Obviously, it is possible that any adjacent Rv are not joined to form a ring.
According to an embodiment of the present disclosure, wherein Y1 to Y5 are, at each occurrence identically or differently, selected from CRy.
According to an embodiment of the present disclosure, wherein X3 to X4 are, at each occurrence identically or differently, selected from CRx or N, X1 to X2 are, at each occurrence identically or differently, selected from C, CRx or N, and one of X1 to X2 is selected from C and joined to the structure
shown in Formula 1.
According to an embodiment of the present disclosure, wherein Z1 to Z8 are, at each occurrence identically or differently, selected from CRz.
According to an embodiment of the present disclosure, wherein V1 and V5 to V8 are, at each occurrence identically or differently, selected from CRv, V2 to V4 are, at each occurrence identically or differently, selected from C or CRv, and one of V2 to V4 is selected from C and joined to Cy.
According to an embodiment of the present disclosure, wherein one of V2 to V4 is selected from C, and at least one of the remaining two of V2 to V4, V1 and V5 to V8 is selected from N. For example, one of them is selected from N or two of them are selected from N.
According to an embodiment of the present disclosure, wherein V4 is selected from C and joined to Cy.
According to an embodiment of the present disclosure, wherein Cy is selected from substituted or unsubstituted alkylene having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkylene having 3 to 20 carbon atoms, substituted or unsubstituted arylene having 6 to 20 carbon atoms, or substituted or unsubstituted heteroarylene having 3 to 20 carbon atoms, and the Cy includes at least one C atom and is joined via the C atom to triazine shown in Formula 1.
According to an embodiment of the present disclosure, wherein Cy is, at each occurrence identically or differently, selected from substituted or unsubstituted phenylene, substituted or unsubstituted biphenylylene, substituted or unsubstituted naphthylene, or substituted or unsubstituted pyridylene.
According to an embodiment of the present disclosure, the compound has a structure represented by Formula 1-1:
shown in Formula 1-1;
Herein, the expression that “adjacent substituents Ru can be optionally joined to form a ring” is intended to mean that any two adjacent substituents Ru can be joined to form a ring. Obviously, it is possible that any adjacent Ru are not joined to form a ring.
According to an embodiment of the present disclosure, wherein U1 to U5 are, at each occurrence identically or differently, selected from C or CRu, and the Ru is, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 20 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 20 carbon atoms, a cyano group, and combinations thereof.
According to an embodiment of the present disclosure, wherein p is 1.
According to an embodiment of the present disclosure, wherein U2 or U3 is C.
According to an embodiment of the present disclosure, wherein V4 is selected from C and joined to U2.
According to an embodiment of the present disclosure, wherein Ar is, at each occurrence identically or differently, selected from substituted or unsubstituted aryl having 6 to 20 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 20 carbon atoms, or combinations thereof.
According to an embodiment of the present disclosure, wherein Ar is, at each occurrence identically or differently, selected from the group consisting of: substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted triphenylenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothienyl, substituted or unsubstituted pyridyl, and combinations thereof.
According to an embodiment of the present disclosure, wherein Rx, Ry, Rz, and Rv are, at each occurrence identically or differently, selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 20 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 20 carbon atoms, a cyano group, and combinations thereof, wherein adjacent substituents Rx can be optionally joined to form a ring, adjacent substituents Ry can be optionally joined to form a ring, adjacent substituents Rz can be optionally joined to form a ring, and adjacent substituents Rv can be optionally joined to form a ring.
According to an embodiment of the present disclosure, wherein Rx, Ry, Rz, and Rv are, at each occurrence identically or differently, selected from the group consisting of hydrogen, deuterium, fluorine, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted triphenylenyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothienyl, and combinations thereof.
According to an embodiment of the present disclosure, wherein the compound is selected from the group consisting of Compound A-1 to Compound A-760, wherein the specific structures of Compound A-1 to Compound A-760 are referred to claim 8.
According to an embodiment of the present disclosure, hydrogens in Compound A-1 to Compound A-760 can be partially or fully substituted with deuterium.
According to an embodiment of the present disclosure, an organic electroluminescent device is further disclosed. The organic electroluminescent device includes:
According to an embodiment of the present disclosure, the organic layer is an emissive layer, and the compound is a host compound.
According to an embodiment of the present disclosure, the organic layer is an electron transporting layer, and the compound is an electron transporting compound.
According to an embodiment of the present disclosure, the organic layer is a hole blocking layer, and the compound is a hole blocking compound.
According to an embodiment of the present disclosure, the organic layer is an emissive layer, the compound is a host compound, and the emissive layer further includes a second host compound, wherein the second host compound includes at least one chemical group selected from the group consisting of: benzene, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolocarbazole, dibenzothiophene, azadibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, triphenylene, azatriphenylene, fluorene, silafluorene, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene, and combinations thereof.
According to an embodiment of the present disclosure, the second host compound includes at least one chemical group selected from the group consisting of: benzene, carbazole, indolocarbazole, fluorene, silafluorene, and combinations thereof.
According to an embodiment of the present disclosure, the second host compound has a structure represented by Formula 2 or Formula 3:
Herein, the expression that “adjacent substituents Rt and Rg can be optionally joined to form a ring” is intended to mean that any one or more of groups of adjacent substituents, such as two substituents Rt, two substituents Rg, and substituents Rt and Rg, may be joined to form a ring. Obviously, it is possible that none of these substituents are joined to form a ring.
According to an embodiment of the present disclosure, the second host compound has a structure represented by one of Formula 2-a to Formula 2-j and Formula 3-a to Formula 3-f.
According to an embodiment of the present disclosure, in Formula 2-a to Formula 2-j and Formula 3-a to Formula 3-f, T is, at each occurrence identically or differently, selected from CRt.
According to an embodiment of the present disclosure, in Formula 2-a to Formula 2-j and Formula 3-a to Formula 3-f, T is, at each occurrence identically or differently, selected from CRt or N, and at least one of T is selected from N, for example, one of T is selected from N or two of T are selected from N.
According to an embodiment of the present disclosure, the second host compound is selected from the group consisting of Compound PH-1 to Compound PH-68:
According to an embodiment of the present disclosure, the organic layer is an emissive layer, the compound is a host compound, and the emissive layer further includes a first metal complex, wherein the first metal complex has a general formula of M(La)m(Lb)n(Lc)q;
In this embodiment, the expression that “adjacent substituents R′, Ru, and R12 can be optionally joined to form a ring” is intended to mean that any one or more of groups of adjacent substituents, such as adjacent substituents R′, adjacent substituents R11, adjacent substituents R12, and adjacent substituents R11 and R12, can be joined to form a ring. Obviously, it is possible that none of these substituents are joined to form a ring.
According to an embodiment of the present disclosure, the ligands Lb and Lc are, at each occurrence identically or differently, selected from the group consisting of the following structures:
In this embodiment, the expression that “adjacent substituents Ra, Rb, Rc, RN1, RN2, RC1, and RC2 can be optionally joined to form a ring” is intended to mean that any one or more of groups of adjacent substituents, such as two substituents Ra, two substituents Rb, two substituents Rc, substituents Ra and Rb, substituents Ra and Rc, substituents Rb and Rc, substituents Ra and RN1, substituents Rb and RN1, substituents Ra and RC1, substituents Ra and RC2, substituents Rb and RC1, substituents Rb and RC2, substituents Ra and RN2, substituents Rb and RN2, and substituents RC1 and RC2, can be joined to form a ring. For example, adjacent substituents Ra and Rb in
can be optionally joined to form a ring, which can form one or more of the following structures including, but not limited to,
wherein W is selected from O, S, Se, NRw or CRwRw, and Rw, Ra′, and Rb′ are defined the same as Ra. Obviously, it is possible that none of these substituents are joined to form a ring.
According to an embodiment of the present disclosure, the first metal complex has a general formula of Ir(La)m(Lb)3-m and has a structure represented by Formula 2-1:
In this embodiment, the expression that “adjacent substituents Ra and Rb can be optionally joined to form a ring” is intended to mean that any one or more of groups of adjacent substituents, such as two substituents Ra, two substituents Rb, and substituents Ra and Rb, may be joined to form a ring. Obviously, it is possible that none of these substituents are joined to form a ring.
In this embodiment, the expression that “adjacent substituents Rd and RT can be optionally joined to form a ring” is intended to mean that any one or more of groups of adjacent substituents, such as two substituents RT and two substituents Rd, may be joined to form a ring. Obviously, it is possible that none of these substituents are joined to form a ring.
According to an embodiment of the present disclosure, at least one of T1 to T6 is selected from CRT, and the RT is selected from substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms.
According to an embodiment of the present disclosure, at least one of T1 to T6 is selected from CRT, and the RT is selected from fluorine or a cyano group.
According to an embodiment of the present disclosure, at least two of T1 to T6 are selected from CRT, one RT is selected from fluorine or a cyano group, and the other RT is selected from substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms.
According to an embodiment of the present disclosure, T1 to T6 are, at each occurrence identically or differently, selected from CRT.
According to an embodiment of the present disclosure, T1 to T6 are, at each occurrence identically or differently, selected from CRT or N, and at least one of T1 to T6 is selected from N, for example, one of T1 to T6 is selected from N or two of T1 to T6 are selected from N.
According to an embodiment of the present disclosure, the first metal complex is selected from the group consisting of Compound GD1 to Compound GD76:
According to an embodiment of the present disclosure, hydrogens in Compound GD1 to Compound GD76 can be partially or fully substituted with deuterium.
According to an embodiment of the present disclosure, the organic electroluminescent device emits green light.
According to an embodiment of the present disclosure, the organic electroluminescent device emits white light.
According to an embodiment of the present disclosure, a compound composition is further disclosed. The compound composition includes a compound represented by Formula 1, wherein the compound is shown in any one of the preceding embodiments.
Combination with Other Materials
The materials described in the present disclosure for a particular layer in an organic light emitting device can be used in combination with various other materials present in the device. The combinations of these materials are described in more detail in U.S. Pat. App. No. 20160359122 at paragraphs 0132-0161, which is incorporated by reference herein in its entirety. The materials described or referred to the disclosure are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.
The materials described herein as useful for a particular layer in an organic light emitting device may be used in combination with a variety of other materials present in the device. For example, materials disclosed herein may be used in combination with a wide variety of emissive dopants, hosts, transporting layers, blocking layers, injection layers, electrodes and other layers that may be present. The combination of these materials is described in detail in paragraphs 0080-0101 of U.S. Pat. App. No. 20150349273, which is incorporated by reference herein in its entirety. The materials described or referred to the disclosure are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.
In the embodiments of material synthesis, all reactions were performed under nitrogen protection unless otherwise stated. All reaction solvents were anhydrous and used as received from commercial sources. Synthetic products were structurally confirmed and tested for properties using one or more conventional equipment in the art (including, but not limited to, nuclear magnetic resonance instrument produced by BRUKER, liquid chromatograph produced by SHIMADZU, liquid chromatograph-mass spectrometry produced by SHIMADZU, gas chromatograph-mass spectrometry produced by SHIMADZU, differential Scanning calorimeters produced by SHIMADZU, fluorescence spectrophotometer produced by SHANGHAI LENGGUANG TECH., electrochemical workstation produced by WUHAN CORRTEST, and sublimation apparatus produced by ANHUI BEQ, etc.) by methods well known to the persons skilled in the art. In the embodiments of the device, the characteristics of the device were also tested using conventional equipment in the art (including, but not limited to, evaporator produced by ANGSTROM ENGINEERING, optical testing system produced by SUZHOU FSTAR, life testing system produced by SUZHOU FSTAR, and ellipsometer produced by BEIJING ELLITOP, etc.) by methods well known to the persons skilled in the art. As the persons skilled in the art are aware of the above-mentioned equipment use, test methods and other related contents, the inherent data of the sample can be obtained with certainty and without influence, so the above related contents are not further described in this present disclosure.
The method for preparing the compound of the present disclosure is not limited herein. Typically, the following compounds are used as examples without limitation, and the synthesis routes and preparation methods thereof are described below.
Intermediate A (22.2 g, 106.0 mmol), Intermediate B (17.7 g, 106.0 mmol), cesium carbonate (Cs2CO3) (69.1 g, 212.0 mmol), and 200 mL of N,N-dimethylformamide (DMF) were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was poured into a large amount of water and extracted with ethyl acetate. The organic phases were collected and concentrated under reduced pressure to give a crude product. The crude product was slurried with absolute ethanol to give Intermediate C (26.7 g, 74.9 mmol) as a white solid with a yield of 70.7%.
Intermediate C (18.9 g, 53.0 mmol), Intermediate D (9.5 g, 77.9 mmol), Pd(PPh3)4 (2.4 g, 2.1 mmol), K2CO3 (14.6 g, 106.0 mmol), 160 mL of toluene, 40 mL of EtOH, and 40 mL of H2O were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was separated into layers, the aqueous phase was extracted with DCM, and the organic phases were combined, dried with anhydrous Na2SO4, filtered, and concentrated under reduced pressure to give a crude product. The crude product was purified through silica gel column chromatography (PE/DCM=10:1 to 8:1) to give Intermediate E (16.8 g, 47.5 mmol) as a white solid with a yield of 89.6%.
Intermediate E (16.8 g, 47.5 mmol), bis(pinacolato)diboron (18.1 g, 71.3 mmol), Pd2(dba)3 (0.87 g, 0.95 mmol), tricyclohexylphosphonium tetrafluoroborate (PCy3·HBF4) (0.70 g, 1.90 mmol), KOAc (9.3 g, 95.0 mmol), and 150 mL of 1,4-dioxane were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was filtered through Celite, and the filtrate was concentrated under reduced pressure to give a crude product. The crude product was purified through silica gel column chromatography (PE/DCM=5:1 to 2:1) to give Intermediate F (18.0 g, 40.4 mmol) as a white solid with a yield of 85.0%.
Intermediate F (15.6 g, 35.0 mmol), Intermediate G (10.3 g, 45.5 mmol), Pd(PPh3)4 (0.8 g, 0.7 mmol), Na2CO3 (7.4 g, 70.0 mmol), 280 mL of THF, and 70 mL of H2O were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was separated into layers, the aqueous phase was extracted with DCM, and the organic phases were combined, dried with anhydrous Na2SO4, filtered, and concentrated under reduced pressure to give a crude product. The crude product was purified through silica gel column chromatography (PE/DCM=10:1 to 3:1) to give Intermediate H (10.5 g, 20.6 mmol) as a light yellow solid with a yield of 58.9%.
Intermediate H (4.3 g, 8.5 mmol), Intermediate I (2.6 g, 8.5 mmol), Pd(PPh3)4 (0.2 g, 0.18 mmol), K2CO3 (2.5 g, 18.0 mmol), 40 mL of toluene, 10 mL of EtOH, and 10 mL of H2O were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was separated into layers, the aqueous phase was extracted with DCM, and the organic phases were combined, dried with anhydrous Na2SO4, filtered, and concentrated under reduced pressure to give a crude product. The crude product was purified through silica gel column chromatography (PE/DCM=10:1 to 3:1) to give a light yellow solid (3.1 g, 4.2 mmol) with a yield of 49.4%. The product was confirmed as the target product Compound A-6 with a molecular weight of 732.2.
Intermediate J (20.9 g, 70.0 mmol), Intermediate G (20.6 g, 91.0 mmol), Pd(PPh3)4 (0.8 g, 0.7 mmol), Na2CO3 (14.8 g, 140.0 mmol), 280 mL of THF, and 70 mL of H2O were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was separated into layers, the aqueous phase was extracted with DCM, and the organic phases were combined, dried with anhydrous Na2SO4, filtered, and concentrated under reduced pressure to give a crude product. The crude product was purified through silica gel column chromatography (PE/DCM=10:1 to 8:1) to give Intermediate K (22.0 g, 60.8 mmol) as a white solid with a yield of 86.9%.
Intermediate K (3.6 g, 10.0 mmol), Intermediate I (3.0 g, 10.0 mmol), Pd(PPh3)4 (0.29 g, 0.23 mmol), K2CO3 (2.8 g, 20.0 mmol), 40 mL of toluene, 10 mL of EtOH, and 10 mL of H2O were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. A large amount of solid was precipitated from the reaction mixture and filtered. The obtained solid was washed with water and ethanol in sequence to give a crude product. The crude product was recrystallized from toluene and slurried with ethanol to give Intermediate L (4.7 g, 8.0 mmol) as a white solid with a yield of 80.0%.
Intermediate L (4.7 g, 8.0 mmol), Intermediate B (1.5 g, 8.8 mmol), cesium carbonate (5.2 g, 16.0 mmol), and 50 mL of DMF were added in sequence to a three-necked round-bottom flask. Under the protection of N2, the reaction mixture was heated to reflux overnight. After the reaction was completed as confirmed by TLC, heating was stopped, and the reaction mixture was cooled to room temperature. The reaction mixture was poured into a large amount of water, a large amount of solid was precipitated and suction filtered under reduced pressure to give a crude product. The crude product was purified through silica gel column chromatography (PE/DCM=10:1 to 4:1) to give a light yellow solid (5.4 g, 2.5 mmol) with a yield of 92.0%. The product was confirmed as the target product Compound A-378 with a molecular weight of 732.2.
Those skilled in the art will appreciate that the above preparation methods are merely exemplary. Those skilled in the art can obtain other compound structures of the present disclosure through the modifications of the preparation methods.
The method for preparing an electroluminescent device is not limited. The preparation methods in the following examples are merely examples and not to be construed as limitations. Those skilled in the art can make reasonable improvements on the preparation methods in the following examples based on the related art. Exemplarily, the proportions of various materials in an emissive layer are not particularly limited. Those skilled in the art can reasonably select the proportions within a certain range based on the related art. For example, taking the total weight of the materials in the emissive layer as reference, a host material may account for 80% to 99% and a light-emitting material may account for 1% to 20%; or the host material may account for 90% to 99% and the light-emitting material may account for 1% to 10%; or the host material may account for 95% to 99% and the light-emitting material may account for 1% to 5%. Further, the host material may include one material or two materials, where a ratio of two host materials may be 100:0 to 1:99; or the ratio may be 80:20 to 20:80; or the ratio may be 60:40 to 40:60. In the examples of the device, the characteristics of the device were also tested using conventional equipment in the art (including, but not limited to, evaporator produced by ANGSTROM ENGINEERING, optical testing system produced by SUZHOU FSTAR, life testing system produced by SUZHOU FSTAR, and ellipsometer produced by BEIJING ELLITOP, etc.) by methods well-known to the persons skilled in the art.
First, a glass substrate having an indium tin oxide (ITO) anode with a thickness of 80 nm was cleaned and then treated with oxygen plasma and UV ozone. After the treatment, the substrate was dried in a glovebox to remove moisture. Then, the substrate was mounted on a substrate holder and placed in a vacuum chamber. Organic layers specified below were sequentially deposited through vacuum thermal evaporation on the ITO anode at a rate of 0.2 to 2 Angstroms per second and a vacuum degree of about 10−8 torr. Compound HT and Compound HT1 were co-deposited as a hole injection layer (HIL). Compound HT was deposited as a hole transporting layer (HTL). Compound PH-23 was deposited as an electron blocking layer (EBL). Compound GD23 was doped with Compound PH-23 and Compound A-6 of the present disclosure and co-deposited as an emissive layer (EML). Compound HB was deposited as a hole blocking layer (HBL). On the hole blocking layer, Compound ET and 8-hydroxyquinolinolato-lithium (Liq) were co-deposited as an electron transporting layer (ETL). Finally, 8-hydroxyquinolinolato-lithium (Liq) with a thickness of 1 nm was deposited as an electron injection layer, and Al with a thickness of 120 nm was deposited as a cathode. The device was transferred back to the glovebox and encapsulated with a glass lid such that the device was completed.
The preparation method in Device Example 2 was the same as that in Device Example 1, except that Compound A-6 of the present disclosure was replaced with Compound A-378 of the present disclosure in the emissive layer (EML).
The preparation method in Device Comparative Example 1 was the same as that in Device Example 1, except that Compound A-6 of the present disclosure was replaced with Compound C-1 in the emissive layer (EML).
The preparation method in Device Comparative Example 2 was the same as that in Device Example 1, except that Compound A-6 of the present disclosure was replaced with Compound C-2 in the emissive layer (EML).
Detailed structures and thicknesses of layers of the devices are shown in the following table. The layers using more than one material were obtained by doping different compounds at their mass ratios as recorded.
The structures of the compounds used in the devices are as follows:
Table 2 shows the CIE data, drive voltage, external quantum efficiency (EQE), and current efficiency (CE) measured at a constant current of 15 mA/cm2 and the device lifetime (LT97) measured at a constant current of 80 mA/cm2.
As can be seen from the data in Table 2, the device in Comparative Example 1 already show excellent performance in terms of drive voltage, EQE, and CE; the device in Example 1 is substantially equivalent or slightly improved compared to Comparative Example 1 in terms of these device properties, and more importantly, the device lifetime of the device in Example 1 is unexpectedly greatly improved by 574 times compared with that in Comparative Example 1. The device in Example 1 and the device in Comparative Example 1 differ only in that dibenzothienyl in the host compound is joined to phenylene through different linking positions. The above data illustrates that compared with the compound in the related art in which 1-position of dibenzothiophene is joined to phenylene, the compound having a specific dibenzothiophene linking position according to the present disclosure enables the electroluminescent device to have excellent overall device performance when the compound is applied to the electroluminescent device, and in particular, can significantly improve the device lifetime, thereby proving the excellent performance of the compound of the present disclosure with the specific structure design of Formula 1.
As can be seen from the data in Table 2, the voltage of the device in Comparative Example 2 is already at a low voltage level; the device in Example 1 is also at a low voltage level as is the device in Comparative Example 2. Both the EQE and the CE of the device in Comparative Example 2 are already at a high efficiency level; while, for the device in Example 1, the EQE is further increased by 4.7%, the CE is further increased by 4.3%, and the device lifetime is also greatly improved by 96.2% than the high level in Comparative Example 2. The device in Example 1 and the device in Comparative Example 2 differ only in that dibenzothienyl in the host compound is joined to the triazine fragment through different linking groups. The above data illustrates that compared with the compound in which triazine is joined to dibenzothienyl through the N atom in the linked carbazolyl, the compound having a specific Cy linking group according to the present disclosure enables the electroluminescent device to have excellent overall device performance when the compound is applied to the electroluminescent device, and in particular, can significantly improve the device lifetime, thereby proving the excellent performance of the compound of the present disclosure with the specific structure design of Formula 1.
In addition, compared with the device in Example 1, although the compound used in Example 2 has a different carbazole linking position, the device in Example 2 still has excellent performance such as a low drive voltage, a high EQE and a high CE, and a longer device lifetime, which are similar to those of the device in Example 1. In particular, the device lifetime is advantageous over the device lifetime in both Comparative Example 1 and Comparative Example 2. The above data further proves the excellent performance of the compound the present disclosure with the specific structure design of Formula 1.
In summary, the compound of the present disclosure, when applied to the organic electroluminescent device, can improve the overall performance of the device, in particular, can significantly improve the device lifetime, and has a wide application prospect.
It should be understood that various embodiments described herein are merely embodiments and not intended to limit the scope of the present disclosure. Therefore, it is apparent to those skilled in the art that the present disclosure as claimed may include variations of specific embodiments and preferred embodiments described herein. Many of the materials and structures described herein may be replaced with other materials and structures without departing from the spirit of the present disclosure. It should be understood that various theories as to why the present disclosure works are not intended to be limitative.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202310070285.5 | Jan 2023 | CN | national |
