Organic electroluminescent materials and devices

Abstract

To provide compounds for use as emitters employed in devices, such as organic light emitting diodes and the like.SOLUTION: A compound includes a ligand L represented by the formula in the figure. (In the formula, each of R1, R2, R3, R4, R4, R5, R6, R7 and R8 is independently selected from a variety of substituents; any adjacent substituents are optionally joined or fused into a ring; etc.)SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 320,915, filed Apr. 11, 2016, and U.S. Provisional Application No. 62 / 368,518, filed Jul. 29, 2016, the entire disclosures of which are hereby incorporated by reference.

[0002] The present invention relates to compounds for use as emitters and devices such as organic light emitting diodes that include such compounds.

Background Art

[0003] Optoelectronic devices that utilize organic materials are becoming increasingly desirable for several reasons. Many of the materials used to fabricate such devices are relatively inexpensive, so organic optoelectronic devices have the potential for cost advantages over inorganic devices. Additionally, the inherent properties of organic materials such as flexibility can make the materials well-suited for certain applications such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, the organic materials can have performance advantages over conventional materials. For example, the wavelength at which the organic emissive layer emits light can generally be readily tuned with appropriate dopants.

[0004] OLEDs utilize thin organic films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as flat panel displays, lighting, and backlighting. Several OLED materials and configurations are described in Patent Documents 1, 2, and 3, the entire disclosures of which are hereby incorporated by reference.

[0005] One use of the phosphorescent emitting molecules is a full-color display. The industry standard for such displays requires pixels adapted to emit specific colors referred to as "saturated" colors. In particular, these standards require saturated red, green, and blue pixels. Alternatively, the OLED can be designed to emit white light. Conventional liquid crystal display emission from a white backlight is filtered using absorption filters to produce red, green, and blue emission. A similar technique can be used with OLEDs. The white OLED can be either a single EML device or a stacked structure. Color can be measured using CIE coordinates well known in the art.

[0006] An example of a green emitting molecule has the following structure:

Chemical formula

[0007] In this drawing and the subsequent drawings in this specification, the inventors depict the coordination bond from nitrogen to the metal (here Ir) as a straight line.

[0008] As used herein, the term "organic" includes polymeric materials and small molecule organic materials that can be used to fabricate organic optoelectronic devices. "Small molecule" refers to any organic material that is not a polymer, and a "small molecule" can actually be quite large. A small molecule can include repeating units in some situations. For example, the use of a long-chain alkyl group as a substituent does not exclude a molecule from the "small molecule" class. A small molecule may be incorporated into a polymer, for example, as a pendant group on a polymer backbone or as part of the backbone. A small molecule can also serve as the core portion of a dendrimer consisting of a series of chemical shells built on the core portion. The core portion of the dendrimer can be a fluorescent or phosphorescent small molecule emitter. A dendrimer can be a "small molecule", and it is believed that all dendrimers currently used in the field of OLEDs are small molecules.

[0009] As used herein, "top" means the furthest from the substrate, while "bottom" means the closest to the substrate. When a first layer is described as being "disposed on top of" a second layer, the first layer is disposed further from the substrate. There may be other layers between the first layer and the second layer unless it is specified that the first layer is "in contact with" the second layer. For example, the cathode can be described as being "disposed on top of" the anode even if there are various organic layers in between.

[0010] As used herein, "solution processable" means capable of being dissolved, dispersed, or transported in a liquid medium in either solution or suspension form and / or capable of being deposited from the medium.

[0011] A ligand can be termed "photoactive" if the ligand is considered to directly contribute to the photoactive properties of the emissive material. A ligand can be termed "auxiliary" if the ligand is considered not to contribute to the photoactive properties of the emissive material, although an auxiliary ligand can modify the properties of the photoactive ligand.

[0012] As used herein, as would be generally understood by one of ordinary skill in the art, the first "highest occupied molecular orbital" (HOMO) or "lowest unoccupied molecular orbital" (LUMO) energy level is "greater" or "higher" than the second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Since the ionization potential (IP) is measured as a negative energy relative to the vacuum level, a higher HOMO energy level corresponds to an IP with a smaller absolute value (less negative IP). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) with a smaller absolute value (less negative EA). In a conventional energy level diagram with the vacuum level at the top, the LUMO energy level of a material is higher than the HOMO energy level of the same material. A "higher" HOMO or LUMO energy level appears to be closer to the top of such a diagram than a "lower" HOMO or LUMO energy level.

[0013] As used herein, as would be generally understood by one of ordinary skill in the art, if the first work function has a higher absolute value, the first work function is "greater" or "higher" than the second work function. Since the work function is generally measured as a negative number relative to the vacuum level, this means that a "higher" work function is more negative. In a conventional energy level diagram with the vacuum level at the top, a "higher" work function is illustrated as being further away in the downward direction from the vacuum level. Thus, the definitions of the HOMO and LUMO energy levels follow a convention different from that of the work function.

[0014] Further details regarding OLEDs and the definitions described above can be found in Patent Document 4, which is hereby incorporated by reference in its entirety.

SUMMARY OF THE INVENTION

[0015] According to an embodiment, a compound is provided that includes a ligand L represented by the following formula.

CHEMICAL

[0016] According to other embodiments, an organic light emitting diode / device (OLED) is also provided. The OLED can include an anode, a cathode, and an organic layer disposed between the anode and the cathode. The organic layer can include a compound containing a ligand L represented by the following formula.

Chemical formula

[0017] According to still other embodiments, a composition is provided that includes a compound containing a ligand L represented by the following formula.

Chemical formula

Brief Description of the Drawings

[0018]

Figure 1

[0019]

Figure 2

Embodiments for Carrying Out the Invention

[0020] Generally, an OLED includes at least one organic layer disposed between and electrically connected to an anode and a cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons move to the oppositely charged electrodes, respectively. When an electron and a hole are localized on the same molecule, an "exciton", which is a localized electron-hole pair having an excited energy state, is formed. Light is emitted via a photoelectron emission mechanism when the exciton relaxes. In some cases, the exciton can be localized on an excimer or an exciplex. Non-radiative mechanisms such as thermal relaxation may occur, but are generally considered undesirable.

[0021] Initial OLEDs used luminescent molecules ("fluorescence") that emit light from their singlet state, as disclosed, for example, in U.S. Patent No. 4,769,292, which is incorporated herein by reference in its entirety. Fluorescent emission generally occurs within a time frame of less than 10 nanoseconds.

[0022] More recently, OLEDs having luminescent materials ("phosphorescence") that emit light from their triplet state have been demonstrated. Baldo et al., "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices", 395, 151 - 154, 1998; ("Baldo-I") and Baldo et al., "Very high-efficiency green organic light emitting devices based on electrophosphorescence", Appl. Phys. Lett., 75, No. 3, 4 - 6 (1999) ("Baldo-II"), which are incorporated herein by reference in their entirety. Phosphorescence is described in more detail in U.S. Patent No. 7,279,704, columns 5 - 6, which is incorporated herein by reference.

[0023] Figure 1 shows an organic light emitting device 100. The figure is not necessarily to scale. Device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, a light emitting layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, a protective layer 155, a cathode 160, and a barrier layer 170. Cathode 160 is a composite cathode having a first conductive layer 162 and a second conductive layer 164. Device 100 may be fabricated by depositing the described layers in sequence. The characteristics, functions, and material examples of these various layers are described in more detail in US7,279,704, incorporated by reference, in paragraphs 6 - 10.

[0024] For each of these layers, further examples are available. For example, the flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated herein by reference in its entirety. An example of a p-doped hole transport 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 herein by reference in its entirety. Examples of the light-emitting material and the host material are disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated herein by reference in its entirety. An example of an n-doped electron transport 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 herein by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated herein by reference in their entireties, disclose examples of cathodes including a composite cathode having a thin layer of a metal such as Mg:Ag with a transparent, conductive, sputter-deposited ITO layer covering the top. The theory and use of the blocking layer are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, which are incorporated herein by reference in their entireties. Examples of the injection layer are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated herein by reference in its entirety. A description of the protective layer can be found in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated herein by reference in its entirety.

[0025] Figure 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, a light-emitting layer 220, a hole transport layer 225, and an anode 230. Device 200 can be fabricated by depositing the described layers in sequence. The most common OLED configuration has a cathode disposed on top of the anode, and since device 200 has a cathode 215 disposed under the anode 230, device 200 may be referred to as an "inverted" OLED. Materials similar to those described for device 100 may be used in the corresponding layers of device 200. Figure 2 provides an example of how some layers can be omitted from the structure of device 100.

[0026] The simple layer structures illustrated in FIGS. 1 and 2 are provided as non-limiting examples, and it is understood that embodiments of the present invention can be used in connection with a wide variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. A functional OLED can be realized by combining the various described layers in various ways, or the layers can be omitted entirely based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many of the examples provided herein describe the various layers as including a single material, it is understood that combinations of materials such as mixtures of hosts and dopants, or more generally mixtures, may be used. Also, the layers may have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, the hole transport layer 225 transports holes and injects holes into the light-emitting layer 220 and may be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED may be described as having an "organic layer" disposed between the cathode and the anode. The organic layer may include a single layer or may further include multiple layers of different organic materials as described, for example, with respect to FIGS. 1 and 2.

[0027] It is also possible to use structures and materials not specifically described, such as OLEDs (PLEDs) composed of polymer materials such as those disclosed in Friend et al.'s U.S. Patent No. 5,247,190, which is incorporated herein by reference in its entirety. As a further example, an OLED having a single organic layer may be used. The OLEDs may be stacked, for example, as described in Forrest et al.'s U.S. Patent No. 5,707,745, which is incorporated herein by reference in its entirety. The OLED structure may deviate from the simple layer structures illustrated in FIGS. 1 and 2. For example, the substrate may include angled reflective surfaces for improving outcoupling, such as mesa structures as described in Forrest et al.'s U.S. Patent No. 6,091,195, which is incorporated herein by reference in its entirety, and / or recessed structures as described in Bulovic et al.'s U.S. Patent No. 5,834,893, which is incorporated herein by reference in its entirety.

[0028] Unless otherwise specified, any of the layers of the various embodiments can be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation such as those described in U.S. Patent Nos. 6,013,982 and 6,087,196, which are incorporated herein by reference in their entirety, inkjet, organic vapor deposition (OVPD) such as those described in U.S. Patent No. 6,337,102 to Forrest et al., which is incorporated herein by reference in its entirety, and deposition by organic vapor jet printing (OVJP) such as those described in U.S. Patent No. 7,431,968, which is incorporated herein by reference in its entirety. Other suitable deposition methods include spin coating and other solution-based processes. Solution-based processes are preferably performed in a nitrogen or inert atmosphere. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include masking such as those described in U.S. Patent Nos. 6,294,398 and 6,468,819, which are incorporated herein by reference in their entirety, deposition via cold welding, and patterning associated with some of the deposition methods such as inkjet and OVJD. Other methods may be used. The materials to be deposited can be modified to be compatible with a particular deposition method. For example, substituents such as alkyl and aryl groups that are branched or unbranched and preferably contain at least 3 carbons can be used in small molecules to enhance the ability to undergo solution processing. Substituents having 20 or more carbons may be used, with 3 to 20 carbons being the preferred range. Materials having an asymmetric structure may have better solution processability than those having a symmetric structure, because asymmetric materials may have a lower tendency to recrystallize. Dendrimer substituents can be used to enhance the ability of small molecules to undergo solution processing.

[0029] Devices fabricated in accordance with embodiments of the present invention may further include a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damaging exposure to harmful species in an environment containing moisture, vapor, and / or gas, etc. The barrier layer can be deposited on the substrate, above, below or adjacent to the electrodes, or on any other part of the device including the edges. The barrier layer may include a single layer or multiple layers. The barrier layer can be formed by various known chemical vapor deposition techniques and can include compositions having a single phase and compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate inorganic or organic compounds or both. Preferred barrier layers include mixtures of polymeric and non-polymeric materials as described in U.S. Patent No. 7,968,146, PCT Patent Application Nos. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are hereby incorporated by reference in their entirety. For a mixture to be considered a "mixture", the polymeric and non-polymeric materials constituting the barrier layer should be deposited under the same reaction conditions and / or simultaneously. The weight ratio of the polymeric material to the non-polymeric material can range from 95:5 to 5:95. The polymeric and non-polymeric materials can be made from the same precursor material. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric silicon and inorganic silicon.

[0030] Devices fabricated in accordance with embodiments of the present invention can be incorporated into a wide variety of electronic component modules (or units) that can be incorporated into various electrical products or intermediate components. Such electrical products or intermediate components include display screens, lighting devices (such as discrete light source devices or lighting panels), which can be utilized by end-user product manufacturers. Such electronic component modules can optionally include drive electronics and / or power supplies. Devices fabricated in accordance with embodiments of the present invention can be incorporated into a wide variety of consumer products having one or more incorporated electronic component modules (or units). Such consumer products include any type of product that includes one or more light sources and / or one or more certain types of display devices. Some examples of such consumer products include flat panel displays, computer monitors, medical monitors, televisions, bulletin boards, indoor or outdoor lighting and / or lights for signal transmission, head-up displays, fully or partially transparent displays, flexible displays, laser printers, telephones, mobile phones, tablets, phablets, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays (displays less than 2 inches diagonal), 3-D displays, virtual reality or augmented reality displays, vehicles, video walls including multiple displays arranged side by side, theater or stadium screens, and billboards. Various control mechanisms including passive matrix and active matrix can be used to control devices fabricated in accordance with the present invention. Many of the devices are intended for use within a temperature range comfortable for humans, such as from 18 degrees Celsius to 30 degrees Celsius, more preferably room temperature (20 to 25 degrees Celsius), but can also be used outside of this temperature range, for example, from -40 degrees Celsius to +80 degrees Celsius.

[0031] The materials and structures described herein may have applications in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may use the materials and structures. More generally, organic devices such as organic transistors may use the materials and structures.

[0032] As used herein, the terms “halo,” “halogen,” or “halide” include fluorine, chlorine, bromine, and iodine.

[0033] As used herein, the term “alkyl” means both straight-chain and branched-chain alkyl groups. Preferred alkyl groups include those containing from 1 to 15 carbon atoms, such as methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, and 2,2-dimethylpropyl. Further, the alkyl group may be substituted.

[0034] As used herein, the term “cycloalkyl” means a cyclic alkyl group. Preferred cycloalkyl groups include those containing 3 to 10 ring carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, and adamantyl. Further, the cycloalkyl group may be substituted.

[0035] As used herein, the term “alkenyl” means both straight-chain and branched-chain alkenyl groups. Preferred alkenyl groups are alkenyl groups containing 2 to 15 carbon atoms. Further, the alkenyl group may be substituted.

[0036] As used herein, the term “alkynyl” means both straight-chain and branched-chain alkynyl groups. Preferred alkynyl groups are alkynyl groups containing 2 to 15 carbon atoms. Further, the alkynyl group may be substituted.

[0037] As used herein, the terms "aralkyl" or "arylalkyl" are used interchangeably and mean an alkyl group having an aromatic group as a substituent. Further, the aralkyl group may be substituted.

[0038] As used herein, the term "heterocyclic group" means an aromatic ring group and a non-aromatic ring group. A heteroaromatic ring group also means heteroaryl. Preferred hetero non-aromatic ring groups are at least one heteroatom containing 3 to 7 ring atoms, including cyclic amines such as morpholino, piperidino, pyrrolidino, etc., and including cyclic ethers such as tetrahydrofuran, tetrahydropyran, etc. Further, the heterocyclic group may be substituted.

[0039] As used herein, the terms "aryl" or "aromatic group" mean monocyclic and polycyclic systems. Polycyclic means having two or more rings in which two carbons are shared by two adjacent rings (the rings are "fused"), and at least one of the rings is aromatic, for example, the other rings may be cycloalkyl, cycloalkenyl, aryl, heterocyclic, and / or heteroaryl. Preferred aryl groups contain 6 to 30 carbon atoms, preferably those containing 6 to 20 carbon atoms, and more preferably those containing 6 to 12 carbon atoms. Aryl groups having 6 carbons, 10 carbons, or 12 carbons are particularly preferred. Suitable aryl groups include phenyl, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene, etc., and phenyl, biphenyl, triphenyl, triphenylene, fluorene, and naphthalene are preferred. Further, the aryl group may be substituted.

[0040] As used herein, the term "heteroaryl" means a monocyclic heteroaromatic group that can contain 1 to 5 heteroatoms. The term heteroaryl also includes polycyclic heteroaromatic systems having two or more rings in which two atoms are shared by two adjacent rings (the rings are "fused"), at least one of the rings being heteroaryl, for example, the other rings can be cycloalkyl, cycloalkenyl, aryl, heterocycle, and / or heteroaryl. Preferred heteroaryl groups are those containing 3 to 30 carbon atoms, preferably those containing 3 to 20 carbon atoms, and more preferably those containing 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, 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, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine, and dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborine, 1,3-azaborine, 1,4-azaborine, borazine, and their aza analogs are preferred. Further, the heteroaryl group may be substituted.

[0041] The alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocycle, aryl, and heteroaryl are unsubstituted or may be substituted with one or more substituents selected from deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, cyclic amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0042] As used herein, "substituted" means that a substituent other than H is attached to the relevant position such as carbon. Thus, for example, when R 1 is monosubstituted, R 1 must be other than H. Similarly, when R 1 is disubstituted, two of R 1 must be other than H. Similarly, when R 1 is unsubstituted, R 1 is hydrogen at all substitution positions.

[0043] As used herein, the term "aza" in fragments described herein, such as aza-dibenzofuran, aza-dibenzothiophene, etc., means that one or more of the C-H groups in each fragment can be replaced by a nitrogen atom. For example, without limitation, azatriphenylene encompasses both dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. One of ordinary skill in the art can readily envision other nitrogen analogs of the above-described aza derivatives, and all such analogs are intended to be encompassed by the terms described herein.

[0044] It should be understood that when a molecular fragment is described as a substituent or as being attached to another moiety, its name may be described as the fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuryl) or the whole molecule (benzene, naphthalene, dibenzofuran). In this specification, these are considered equivalent even if the way of representing the substituent or the attached fragment is different.

[0045] According to one embodiment, a compound is described that includes a ligand L represented by the following formula.

Chemical formula

[0046] In some embodiments, ring A is bonded to ring C in the para - position with respect to the N of ring C. In some embodiments, ring A is bonded to ring C in the meta - position with respect to the N of ring C. In some embodiments, ring B is bonded to ring C in the para - position with respect to the N of ring C, or ring B is bonded to the adjacent ring A in the para - position with respect to ring C, or is bonded to the adjacent ring A. In some embodiments, ring B is bonded to ring C in the meta - position with respect to the N of ring C, or ring B is bonded to the adjacent ring A in the meta - position with respect to ring C, or is bonded to the adjacent ring A.

[0047] In some embodiments, M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu. In some embodiments, M is Ir or Pt.

[0048] In some embodiments, the compound is homoleptic. In other embodiments, the compound is heteroleptic.

[0049] In some embodiments, (i) when a is 0, at least one of R 7 、R 8 、and R adjacent to ring B 2At least one of which is selected from the group consisting of alkyl, cycloalkyl, partially or fully deuterated variants thereof, and combinations thereof, (ii) when a is from 1 to 10, R adjacent to ring A 2 and R adjacent to ring C 6 At least one of which is selected from the group consisting of alkyl, cycloalkyl, partially or fully deuterated variants thereof, and combinations thereof.

[0050] In some embodiments, at least one of R 3 , R 4 , and R 5 is selected from the group consisting of alkyl, cycloalkyl, fluorine, partially or fully deuterated variants thereof, and combinations thereof.

[0051] In some embodiments, R 1 is hydrogen.

[0052] In some embodiments, (i) when a is 0, at least one R adjacent to ring B 2 is not hydrogen, and at least one of R 7 and R 8 is not hydrogen, (ii) when a is from 1 to 10, at least one R adjacent to ring A 2 is not hydrogen, and at least one R adjacent to ring C 6 is not hydrogen.

[0053] In some embodiments, when a is from 1 to 10, R 7 and R 8 are hydrogen. In some embodiments, a is from 2 to 10.

[0054] In some embodiments, the ligand L is selected from the group consisting of the following.

Chemical formula

[0055] In some embodiments, the ligand L is selected from the group consisting of L as defined in the following table based on the following structure A1 ~L A1432 , L B1 ~L B1432 , L C1 ~L C1432 , L D1 ~L D1432 and so on.

Chemical Structure

Table A-1

Table A-2

Table A-3

Table A-4

Table A-5

Table A-6

Table A-7

Table A-8

Table A-9

Table A-10

Table A-11

Table A-12

Table A-13

Table A-14

Table A-15

Table A-16

Table A-17

Table A-18

Table A-19

Table A-20

Table A-21

Table A-22

Table A-23

Table A-24

Table A-25

Table A-26

Table A-27

Table A-28

Table A-29

Table A-30

Table A-31

Table A-32

Table A-33

Table A-34

Table A-35

Table A-36

Table A-37

Table A-38

Table A-39

Table A-40

Table A-41

Table A-42

Table A-43

Table A-44

Table A-45

Table A-46

Table A-47

Table A-48

Table A-49

Table A-50

Table A-51

Table A-52

Table A-53

Table A-54

Table A-55

Table A-56

Table A-57

Table A-58

Table A-59

Table A-60

Table A-61

Table A-62

Table A-63

Table A-64

Table A-65

Table A-66

Table A-67

Table A-68

Table A-69

Table A-70

[0056] In some embodiments, the compound is ML n (L B ) m-n and is represented by the formula wherein M is Ir or Pt; L B is a bidentate ligand; when M is Ir, m is 3 and n is 1, 2, or 3; when M is Pt, m is 2 and n is 1 or 2.

[0057] In some such embodiments, the compound is represented by the formula IrL3. In some such embodiments, the compound is represented by the formula IrL(L B )2; L B is different from L.

[0058] In some embodiments, the compound is represented by the formula Ir(L)2(L B ) and L B is different from L.

[0059] In some embodiments, the compound is represented by the formula Pt(L)(L B ) and L and L B can be the same or different. In some such embodiments, L and L B are bonded to form a tetradentate ligand. In some embodiments, L and L B are bonded at two positions to form a macrocyclic tetradentate ligand.

[0060] When the compound is ML n (L B ) m-nIn some embodiments represented by the formula, (i) M is Ir, m is 3, n is 1 or 2, or (ii) M is Pt, m is 2, n is 1; L B is selected from the group consisting of the following.

Chemical formula

Chemical formula

[0061] When the compound is ML n (LB ) m-n In some embodiments represented by the formula, (i) M is Ir, m is 3, n is 1 or 2, or (ii) M is Pt, m is 2, n is 1; L B is selected from the group consisting of L B1 ~L B300 below.

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0062] In the organometallic complex, the ligand L can be L A1 ~L A1432 、L B1 ~L B1432 、L C1 ~L C1432 、and L D1 ~L D1432 and L B can be other ligands. Therefore, it can be easily understood that the ligand L B1 ~L B1432 is distinguishable from L B1 ~L B300 .

[0063] In some embodiments, the compound is selected from the group consisting of compound A-1 to compound A-429,600, compound B-1 to compound B-429,600, compound C-1 to compound C-429,600, and compound D-1 to compound D-429,600, Compound k-x is represented by the formula Ir(L ki )(L Bj )2; wherein x = 300i + j - 300; k is A, B, C, or D; i is an integer from 1 to 1430, and j is an integer from 1 to 300; L B1 ~L B300 is represented by the structure provided herein.

[0064] In some embodiments, the compound can be a luminescent dopant. In some embodiments, the compound can generate luminescence through phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also referred to as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0065] In other embodiments, an organic light emitting device (OLED) is described that includes an anode; a cathode; and an organic layer disposed between the anode and the cathode. In some embodiments, consumer products including the OLEDs described herein are described. The organic layer includes a compound having a ligand L represented by the following formula, as described herein.

Chem.

[0066] According to another aspect of the present disclosure, a composition is provided that includes a compound having a ligand L represented by the following formula.

Chem.

[0067] The OLEDs disclosed herein can be incorporated into one or more of consumer products, electronic component modules, and lighting panels. The organic layer can be an emissive layer, and in some embodiments, the compound can be an emissive dopant, and in other embodiments, the compound can be a non-emissive dopant.

[0068] The organic layer can also include a host. In some embodiments, two or more hosts are preferred. In some embodiments, the host used can be a) a bipolar material, b) an electron transport material, c) a hole transport material, or d) a wide bandgap material with little role in charge transport. In some embodiments, the host can include a metal complex. The host can be a triphenylene containing a benzo-fused thiophene or a benzo-fused furan. Any substituent in the host can independently be C n H 2n+1 、OC n H 2n+1 、OAr1、N(C n H 2n+1 )2、N(Ar1)(Ar2)、CH=CH-C n H2n+1 , C≡C-C n H 2n+1 , Ar1, Ar1-Ar2, and C n H 2n -Ar1 can be a non-condensed substituent selected from the group consisting of, or the host can be unsubstituted. In the foregoing substituents, n can range from 1 to 10, and Ar1 and Ar2 can independently be selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof. The host can be an inorganic compound. For example, Zn-containing inorganic materials such as ZnS can be mentioned.

[0069] The host can be a compound containing at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene. The host can contain a metal complex. The host can be a specific compound selected from the group consisting of the following, but is not limited thereto.

Chemical formula

Chemical formula

[0070] According to another aspect of the present invention, a composition containing a compound represented by formula I is disclosed. The composition can contain one or more components selected from the group consisting of solvents, hosts, hole injection materials, hole transport materials, and electron transport layer materials disclosed herein. Combinations with other materials

[0071] The materials described herein as useful for a particular layer in an organic light emitting device can be used in combination with a wide variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a wide variety of hosts, transport layers, blocking layers, injection layers, electrodes, and other layers that may be present. The materials described or referenced below are non-limiting examples of materials that can be useful in combination with the compounds disclosed herein, and one of ordinary skill in the art can readily peruse the literature to identify other materials that can be useful in combination.

[0072] Conductive dopant: The charge transport layer is doped with a conductive dopant, which greatly changes the density of charge carriers and thereby its conductivity. Conductivity can be increased by generating charge carriers in the matrix material or depending on the type of dopant, and changes in the Fermi level of the semiconductor can also be achieved. The hole transport layer can be doped with a p-type conductive dopant, and the n-type conductive dopant is used in the electron transport layer.

[0073] Non-limiting examples of conductive dopants that can be used in an OLED in combination with the materials disclosed herein are exemplified below along with the literature disclosing these materials. EP01617493, EP01968131, EP2020694, EP2684932, US20050139810, US20070160905, US20090167167, US2010288362, WO06081780, WO2009003455, WO2009008277, WO2009011327, WO2014009310, US2007252140, US2015060804, US2012146012

Chemical formula

[0074] The hole injection / transport materials used in the embodiments of the present invention are not particularly limited, and any compound may be used as long as the compound is typically used as a hole injection / transport material. Examples of the materials include phthalocyanine or porphyrin derivatives; aromatic amine derivatives; indolocarbazole derivatives; polymers containing fluorinated hydrocarbons; polymers having a conductive dopant; conductive polymers such as PEDOT / PSS; self-assembled monomers derived from compounds such as phosphonic acids and silane derivatives; metal oxide derivatives such as MoO x and the like; p-type semiconductor organic compounds such as 1,4,5,8,9,12-hexaazatriphenylene hexacarbonitrile; metal complexes, and crosslinkable compounds, but are not limited thereto.

[0075] Examples of the aromatic amine derivatives used in the HIL or HTL include, but are not limited to, those having the following general structure. [Chemical formula]

[0076] Ar 1 to Ar 9Each of them is selected from the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene, etc.; dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, 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, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine and selenophenodipyridine, etc.; and a group consisting of 2 to 10 cyclic structural units which are the same or different kinds of groups selected from an aromatic hydrocarbon cyclic group and an aromatic heterocyclic group, and are bonded to each other directly or through at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom, a boron atom, a chain structural unit and an aliphatic cyclic group. Each Ar can be unsubstituted or substituted by a substituent selected from the group consisting of deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino and combinations thereof.

[0077] In one embodiment, Ar 1 from Ar9 is selected independently from the group consisting of [Chem.] . Wherein k is an integer from 1 to 20; X 101 to X 108 is C (including CH) or N; Z 101 is NAr 1 , O, or S; Ar 1 has the same group as defined above.

[0078] Examples of metal complexes used in HIL or HTL include, but are not limited to, the following general formula. [Chem.] Wherein Met is a metal that can have an atomic weight greater than 40; (Y 101 -Y 102 ) is a bidentate ligand, and Y 101 and Y 102 are independently selected from C, N, O, P, and S; L 101 is a auxiliary ligand; k' is an integer value from 1 to the maximum number of ligands that can attach to the metal; and k'+k'' is the maximum number of ligands that can attach to the metal.

[0079] In one aspect, (Y 101 -Y 102 ) is a 2-phenylpyridine derivative. In another aspect, (Y 101 -Y 102 ) is a carbene ligand. In another aspect, Met is selected from Ir, Pt, Os, and Zn. In a further aspect, the metal complex has a minimum oxidation potential of less than about 0.6 V in solution with respect to the Fc + / Fc couple.

[0080] Non-limiting examples of HIL materials and HTL materials that can be used in OLEDs in combination with the materials disclosed herein are exemplified below along with the literature disclosing these materials. CN102702075, DE102012005215, EP01624500, EP01698613, EP01806334, EP01930964, EP01972613, EP01997799, EP02011790, EP02055700, EP02055701, EP1725079, EP2085382, EP2660300, EP650955, JP07 - 073529, JP2005112765, JP2007091719, JP2008021687, JP2014 - 009196, KR20110088898, KR20130077473, TW201139402, US06517957, US20020158242, US20030162053, US20050123751, US20060182993, US20060240279, US20070145888, US20070181874, US20070278938, US20080014464, US20080091025, US20080106190, US20080124572, US20080145707, US20080220265, US20080233434, US20080303417, US2008107919, US20090115320, US20090167161, US2009066235, US2011007385, US20110163302, US2011240968, US2011278551, US2012205642, US2013241401, US20140117329, US2014183517, US5061569, US5639914, WO05075451, WO07125714, WO08023550, WO08023759, WO2009145016, WO2010061824, WO2011075644, WO2012177006, WO2013018530, WO2013039073, WO2013087142, WO2013118812, WO2013120577, WO2013157367, WO2013175747, WO2014002873, WO2014015935, WO2014015937, WO2014030872, WO2014030921, WO2014034791, WO2014104514, WO2014157018 [Chemistry] [Chemistry] [Chemistry] [Chemistry] [Chemistry] [Chemistry] [Chemistry] [Chemistry] EBL:

[0081] The electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons emitted from the light-emitting layer. The presence of such a blocking layer in the device can result in significantly higher efficiency and / or longer lifetime compared to a similar device lacking the blocking layer. Also, the blocking layer can be used to limit light emission to a desired region of the OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or higher triplet energy than the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or higher triplet energy than one or more of the hosts closest to the EBL interface. In one aspect, the compound used in the EBL contains the same molecule or the same functional group as one of the hosts described below. Host:

[0082] The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as a light-emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound may be used as long as the triplet energy of the host is greater than that of the dopant. Any host material may be used with any dopant as long as the triplet criterion is satisfied.

[0083] Examples of the metal complex used as the host material preferably have the following general formula.

Chemical formula

[0084] In one aspect, the metal complex is the following complex.

Chemical formula

[0085] In another aspect, Met is selected from Ir and Pt. In a further aspect, (Y 103 -Y 104 ) is a carbene ligand.

[0086] Examples of other organic compounds used as host materials include the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene, etc.; the group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, 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, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine, etc.; and a group selected from the same or different types of groups selected from aromatic hydrocarbon cyclic groups and aromatic heterocyclic groups, and consisting of 2 to 10 cyclic structural units bonded to each other directly or via at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group. Each option in each group can be unsubstituted or substituted by a substituent selected from the group consisting of deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0087] In one aspect, the host compound contains at least one of the following groups in the molecule.

Chemical formula

[0088] Non-limiting examples of host materials that can be used in OLEDs in combination with the materials disclosed herein are illustrated below along with the literature disclosing these materials. EP2034538, EP2034538A, EP2757608, JP2007254297, KR20100079458, KR20120088644, KR20120129733, KR20130115564, TW201329200, US20030175553, US20050238919, US20060280965, US20090017330, US20090030202, US20090167162, US20090302743, US20090309488, US20100012931, US20100084966, US20100187984, US2010187984, US2012075273, US2012126221, US2013009543, US2013105787, US2013175519, US2014001446, US20140183503, US20140225088, US2014034914, US7154114, WO2001039234, WO2004093207, WO2005014551, WO2005089025, WO2006072002, WO2006114966, WO2007063754, WO2008056746, WO2009003898, WO2009021126, WO2009063833, WO2009066778, WO2009066779, WO2009086028, WO2010056066, WO2010107244, WO2011081423, WO2011081431, WO2011086863, WO2012128298, WO2012133644, WO2012133649, WO2013024872, WO2013035275, WO2013081315, WO2013191404, WO2014142472

Chem.

Chem.

Chem.

Chem.

[0089] One or more additional emitter dopants can be used in combination with the compounds of the present disclosure. Examples of additional emitter dopants are not particularly limited, and any compound can be used as long as the compound is typically used as an emitter material. Suitable emitter materials include, but are not limited to, compounds that can generate light through phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also referred to as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0090] Non-limiting examples of emitter materials that can be used in an OLED in combination with the materials disclosed herein are exemplified below along with the documents that disclose these materials. CN103694277, CN1696137, EB01238981, EP01239526, EP01961743, EP1239526, EP1244155, EP1642951, EP1647554, EP1841834, EP1841834B, EP2062907, EP2730583, JP2012074444, JP2013110263, JP4478555, KR1020090133652, KR20120032054, KR20130043460, TW201332980, US06699599, US06916554, US20010019782, US20020034656, US20030068526, US20030072964, US20030138657, US20050123788, US20050244673, US2005123791, US2005260449, US20060008670, US20060065890, US20060127696, US20060134459, US20060134462, US20060202194, US20060251923, US20070034863, US20070087321, US20070103060, US20070111026, US20070190359, US20070231600, US2007034863, US2007104979, US2007104980, US2007138437, US2007224450, US2007278936, US20080020237, US20080233410, US20080261076, US20080297033, US200805851, US2008161567, US2008210930, US20090039776, US20090108737, US20090115322, US20090179555, US2009085476, US2009104472, US20100090591, US20100148663, US20100244004, US20100295032, US2010102716, US2010105902, US2010244004, US2010270916, US20110057559, US20110108822, US20110204333, US2011215710, US2011227049, US2011285275,US2012292601, US20130146848, US2013033172, US2013165653, US2013181190, US2013334521, US20140246656, US2014103305, US6303238, US6413656, US6653654, US6670645, US6687266, US6835469, US6921915, US7279704, US7332232, US7378162, US7534505, US7675228, US7728137, US7740957, US7759489, US7951947, US8067099, US8592586, US8871361, WO06081973, WO06121811, WO07018067, WO07108362, WO07115970, WO07115981, WO08035571, WO2002015645, WO2003040257, WO2005019373, WO2006056418, WO2008054584, WO2008078800, WO2008096609, WO2008101842, WO2009000673, WO2009050281, WO2009100991, WO2010028151, WO2010054731, WO2010086089, WO2010118029, WO2011044988, WO2011051404, WO2011107491, WO2012020327, WO2012163471, WO2013094620, WO2013107487, WO2013174471, WO2014007565, WO2014008982, WO2014023377, WO2014024131, WO2014031977, WO2014038456, WO2014112450, [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula] [Chemistry] [Chemistry] HBL:

[0091] Using a hole blocking layer (HBL), the number of holes and / or excitons emitted from the light-emitting layer can be reduced. The presence of such a blocking layer in the device can result in significantly higher efficiency and / or longer lifetime compared to a similar device lacking the blocking layer. Also, a blocking layer can be used to limit light emission to a desired region of the OLED. In some embodiments, the HBL material has a lower HOMO (farther from the vacuum level) and / or higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (farther from the vacuum level) and / or higher triplet energy than one or more of the hosts closest to the HBL interface.

[0092] In one aspect, the compound used in the HBL contains the same molecule as that used as the host described above.

[0093] In another aspect, the compound used in the HBL contains at least one of the following groups in the molecule. [Chemistry] where k is an integer from 1 to 20; L 101 is another ligand, and k' is an integer from 1 to 3. ETL:

[0094] The electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or may be doped. Doping can be used to enhance conductivity. Examples of ETL materials are not particularly limited, and any metal complex or organic compound may be used as long as it is typically used for transporting electrons.

[0095] In one aspect, the compound used in the ETL contains at least one of the following groups in the molecule.

Chemical formula

[0096] In another aspect, the metal complex used in the ETL contains, but is not limited to, the following general formula.

Chemical formula

[0097] Non-limiting examples of ETL materials that can be used in OLEDs in combination with the materials disclosed in this specification are exemplified below together with the documents disclosing these materials. CN103508940, EP01602648, EP01734038, EP01956007, JP2004-022334, JP2005149918, JP2005-268199, KR0117693, KR20130108183, US20040036077, US20070104977, US2007018155, US20090101870, US20090115316, US20090140637, US20090179554, US2009218940, US2010108990, US2011156017, US2011210320, US2012193612, US2012214993, US2014014925, US2014014927, US20140284580, US6656612, US8415031, WO2003060956, WO2007111263, WO2009148269, WO2010067894, WO2010072300, WO2011074770, WO2011105373, WO2013079217, WO2013145667, WO2013180376, WO2014104499, WO2014104535.

Chem.

Chem.

Chem.

[0098] In tandem or stacked OLEDs, the CGL plays an important role in performance and consists of an n-doped layer and a p-doped layer for electron and hole injection, respectively. Electrons and holes are supplied from the CGL and the electrodes. The consumed electrons and holes in the CGL are replenished by the electrons and holes injected from the cathode and anode, respectively, and then the bipolar current gradually reaches a stable state. Typical CGL materials include n-type and p-type conductive dopants used in the transport layer.

[0099] In any of the above-mentioned compounds used in each layer of the OLED device, a hydrogen atom may be partially or fully deuterated. Thus, any specifically mentioned substituents such as, but not limited to, methyl, phenyl, pyridyl, etc. can be their non-deuterated, partially deuterated, and fully deuterated versions. Similarly, classes of substituents such as, but not limited to, alkyl, aryl, cycloalkyl, heteroaryl, etc. can also be their non-deuterated, partially deuterated, and fully deuterated versions.

Example

[0100] Compound IrL A1431 (L B91 ) 2 Synthesis

Chemical formula

[0101] Step 1

Chemical formula

[0102] Nitrogen was passed through a 250 mL two-necked round-bottom flask, and then 2-bromo-4-chloro-5-methylpyridine (9.88 g, 47.9 mmol), phenylboronic acid (6.42 g, 52.6 mmol), diacetoxypalladium (0.537 g, 2.393 mmol), triphenylphosphane (2.51 g, 9.57 mmol), potassium hydroxide (5.37 g, 96 mmol), and an acetonitrile (150 ml) / ethanol (75 ml) mixture were added under nitrogen to obtain a red suspension. The reaction mixture was heated to 60 °C for 16 hours under nitrogen. Then, the reaction mixture was cooled to room temperature (about 22 °C), filtered through a pad of silica gel, and evaporated to dryness. The residue was purified by column chromatography (silica gel, heptane / EtOAc = 2 / 1 (v:v)) and crystallized from heptane as colorless crystals (6.5 g, yield 67%).

[0103] Step 2

Chemical formula

[0104] Under nitrogen, 4-chloro-5-methyl-2-phenylpyridine (5 g, 24.55 mmol), (4-cyclohexylphenyl)boronic acid (5.01 g, 24.55 mmol), tripotassium phosphate tribasic monohydrate (11.31 g, 49.1 mmol), tris(dibenzylideneacetone)dipalladium(0) (Pd2(dba)3) (2 mol%), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (SPhos) (4 mol%) were dissolved in a dimethoxyethane (DME) (70 ml) / water (5 ml) mixture to obtain a red suspension. The reaction mixture was degassed and heated to reflux for 16 hours.

[0105] Then, the reaction mixture was cooled to room temperature (about 22 °C). Then, the organic phase was separated, filtered, evaporated, and purified by silica gel column chromatography eluting with heptane / tetrahydrofuran (THF) 9 / 1 (v / v) to obtain a clear solidified colorless oil (6.8 g, yield 85%).

[0106] Step 3 [Chem.]

[0107] Under nitrogen, 4-(4-cyclohexylphenyl)-5-methyl-2-phenylpyridine (6.8 g, 20.77 mmol), ((methyl-d3)sulfinyl)methane-d3 (61.2 g, 727 mmol), and sodium 2-methylpropane-2-olate (0.998 g, 10.38 mmol) were suspended together in a flask. The flask was immersed in an oil bath at 71 °C for 18 h. The reaction mixture was then cooled to room temperature (ca. 22 °C), quenched with 3 eq. of D2O, diluted with brine, and extracted with EtOAc. The organic phase was separated, filtered, evaporated, and purified using a silica gel column eluted with heptane / THF 95 / 5 (v / v) to give colorless crystals (6.0 g, 87% yield).

[0108] Step 4 [Chem.]

[0109] Under nitrogen, methanol-solvated iridium triflate salt (4 g, 5.12 mmol) and 4-(4-(cyclohexyl-1-d)phenyl)-5-(methyl-d3)-2-phenylpyridine (5.94 g, 17.90 mmol) were suspended in an ethanol (30 ml) / methanol (30.0 ml) mixture. The reaction mixture was degassed and then the flask was immersed in an oil bath at 70 °C for 3 days. The reaction mixture was then cooled to room temperature (ca. 22 °C), filtered, and the solid material was dried. The mixture was purified by silica gel column chromatography eluted with a gradient heptane / toluene 4 / 1 to 1 / 4 (v / v) mixture. The pure fractions were evaporated and crystallized from DCM / ethanol to give 1.8 g of a bright yellow solid (39% yield).

[0110] IrL A1432 (LB91 ) 2 Synthesis

Chem.

[0111] Step 1

Chem.

[0112] Under nitrogen, 4-chloro-5-methyl-2-phenylpyridine (6 g, 29.5 mmol), (3,4-dimethylphenyl)boronic acid (4.86 g, 32.4 mmol), and tripotassium phosphate tribasic hydrate (13.57 g, 58.9 mmol) were dissolved in a mixture of DME (60 mL) / water (2 mL) to obtain a colorless suspension. Pd2(dba)3 (0.405 g, 0.442 mmol) and SPhos (0.410 g, 0.884 mmol) were added at once, the reaction mixture was degassed, and heated to 100 °C for 16 h under nitrogen. Then, the reaction mixture was cooled to room temperature (about 22 °C). The organic phase was separated, evaporated, purified by silica gel column chromatography eluting with heptane / THF 95 / 5 (v / v), and then crystallized from heptane to obtain white crystals (7.0 g, yield 85%).

[0113] Step 2

Chem.

[0114] Under nitrogen, 4-(3,4-dimethylphenyl)-5-methyl-2-phenylpyridine (7 g, 25.6 mmol), ((methyl-d3)sulfinyl)methane-d3 (86 g, 1,024 mmol), and sodium 2-methylpropane-2-olate (1.723 g, 17.92 mmol) were dissolved in a flask to obtain a brown solution. The flask was immersed in an oil bath at 71 °C for 14 hours, cooled to room temperature (about 22 °C), quenched with 3 equivalents of D2O, and then diluted with brine. The resulting solution was extracted with EtOAc, the organic extracts were combined, filtered, and evaporated. Column chromatography using a silica gel column eluted with heptane / THF 95 / 5 (v / v) was used to purify the crude material to obtain 4-(3,4-bis(methyl-d3)phenyl)-5-(methyl-d3)-2-phenylpyridine as a white solid (6.0 g, 83% yield).

[0115] Step 3

Chemical formula

[0116] Under nitrogen, in a flask, iridium triflate salt solvated with methanol (2.8 g, 3.58 mmol) and 4-(3,4-bis(methyl-d3)phenyl)-5-(methyl-d3)-2-phenylpyridine (3.03 g, 10.74 mmol) were suspended in an EtOH (30 ml) / MeOH (30.0 ml) mixture to obtain a yellow suspension. The flask was immersed in an oil bath at 71 °C and stirred under nitrogen for 3 days. The resulting mixture was cooled to room temperature (about 22 °C), the resulting yellow solid was filtered, purified by column chromatography using a silica gel column eluted with toluene / heptane 85 / 15 (v / v), and then crystallized from toluene / ethanol and toluene / heptane to obtain a yellow solid (1.8 g, 59% yield). Device Example

[0117] All of the example devices were under high vacuum (<10 -7They were fabricated by thermal evaporation in Torr. The anode electrode was indium tin oxide (ITO) with a thickness of 800 Å. The cathode consisted of 10 Å of Liq (lithium 8-hydroxyquinoline) and 1,000 Å of Al. All the devices were immediately encapsulated with a glass lid sealed with epoxy resin in a nitrogen glove box (H2O and O2 < 1 ppm) after fabrication, and a moisture getter was placed in the package. The organic laminate of the device example consisted of, in order from the ITO surface, 100 Å of HAT-CN as a hole injection layer (HIL); 450 Å of HTM as a hole transport layer (HTL); and a light-emitting layer (EML) with a thickness of 400 Å. The light-emitting layer contained H-host (H1):E-host (H2) in a ratio of 6:4 and 12 wt% of a green emitter. As the ETL, 350 Å of Liq (lithium 8-hydroxyquinoline) was doped with 40% of ETM. Table 1 shows the schematic device structure. The chemical structures of the device materials are shown below. [Chemical formula] [Chemical formula]

[0118] For the fabricated devices, EL, JVL, and lifetime were evaluated at DC 80 mA / cm 2 . Assuming an acceleration factor of 1.8, LT97 at 9,000 nits was calculated from the 80 mA / cm2 LT data. The device performance is shown in Table 2. Table 1: Schematic device structure [Table 1] Table 2: Device performance [Table 2]

[0119] IrL of the example A1431 (L B91 )2 and IrL A1432 (L B91) The efficiency of 2 is higher than that of the comparative example. Probably, the alkyl substitution of the peripheral ring has a better alignment with the transition dipole moment of the molecule. The concept is shown in the following figure. Further, the compound IrL A1431 (L B91 )2 and IrL A1432 (L B91 )2 are both blue-shifted compared to the comparative example having a low device lifetime.

Chemical Formula

[0120] It is understood that the various embodiments described herein are merely examples and are not intended to limit the scope of the present invention. For example, many of the materials and structures described herein can be replaced with other materials and structures without departing from the spirit of the present invention. Therefore, the present invention as claimed can include variations from the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It is understood that the various theories as to why the present invention works are not intended to be limiting.

Prior Art Documents

Patent Documents

[0121]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Explanation of Reference Signs

[0122] 100 Organic light-emitting device 110 Substrate 115 Anode 120 Hole injection layer 125 Hole transport layer 130 Electron blocking layer 135 Light-emitting layer 140 Hole blocking layer 145 Electron transport layer 150 Electron injection layer 155 Protection layer 160 Cathode 162 First conductive layer 164 Second conductive layer 170 Barrier layer 200 Inverted OLED, device 210 Substrate 215 Cathode 220 Light-emitting layer 225 Hole transport layer 230 Anode

Claims

1. A material for an OLED, comprising a ligand L represented by the following formula: 【Chemistry 1】 (In the formula, R １ and R ６ represents mono-, di-, tri-, or tetra-substitution, or represents no substitution; R ２ represents mono-, di-, or tri-substitution, or represents unsubstitution; R １ , R ２ , R ３ , R ４ , R ４ , R ５ , R ６ , R ７ , and R ８ are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , and R ８ any adjacent substituents of may be joined or fused to form a ring; R ３ , R ４ , and R ５ at least one of is not hydrogen; a is an integer from 0 to 10; (i) When a is 0, R ７ , R ８ and R adjacent to ring B ２ (ii) when a is 1 to 10, at least one of R ２ and R adjacent to ring C ６ at least one of is not hydrogen; said ligand L is coordinated to a metal M having an atomic weight of more than 40; The ligand L may be combined with other ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand.

2. 2. The material for an OLED according to claim 1, wherein M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu, or M is Ir or Pt.

3. (i) When a is 0, R ７ , R ８ and R adjacent to ring B ２ is selected from the group consisting of alkyl, cycloalkyl, partially or fully deuterated variants thereof, and combinations thereof; and (ii) when a is 1 to 10, at least one of R adjacent to ring A is ２ and R adjacent to ring C ６ 2. The material for an OLED according to claim 1, wherein at least one of is selected from the group consisting of alkyl, cycloalkyl, partially or fully deuterated variants thereof, and combinations thereof.

4. R ３ , R ４ , and R ５ 2. The material for an OLED according to claim 1, wherein at least one of is selected from the group consisting of alkyl, cycloalkyl, fluorine, partially or fully deuterated variants thereof, and combinations thereof.

5. (i) when a is 0, at least one R adjacent to ring B ２ is not hydrogen, and R ７ and R ８ (ii) when a is 1 to 10, at least one of R ２ is not hydrogen, and at least one R adjacent to ring C ６ The material for an OLED according to claim 1 , wherein is not hydrogen.

6. 2. The material for an OLED according to claim 1, wherein the ligand L is selected from the group consisting of: 【Chemistry 2】

7. The ligand L is defined in the following table based on the following structure: Ａ１ ~L Ａ１４３２ , L Ｂ１ ~L Ｂ１４３２ , L Ｃ１ ~L Ｃ１４３２ , L Ｄ１ ~L Ｄ１４３２ 2. The material for an OLED according to claim 1, selected from the group consisting of: 【Chemistry 3】 【Table A-1】 【Table A-2】 【Table A-3】 【Table A-4】 【Table A-5】 【Table A-6】 【Table A-7】 【Table A-8】 【Table A-9】 【Table A-10】 【Table A-11】 【Table A-12】 【Table A-13】 【Table A-14】 【Table A-15】 【Table A-16】 【Table A-17】 【Table A-18】 【Table A-19】 【Table A-20】 【Table A-21】 【Table A-22】 【Table A-23】 【Table A-24】 【Table A-25】 【Table A-26】 【Table A-27】 【Table A-28】 【Table A-29】 【Table A-30】 【Table A-31】 【Table A-32】 【Table A-33】 【Table A-34】 【Table A-35】 【Table A-36】 【Table A-37】 【Table A-38】 【Table A-39】 【Table A-40】 【Table A-41】 【Table A-42】 【Table A-43】 【Table A-44】 【Table A-45】 【Table A-46】 【Table A-47】 【Table A-48】 【Table A-49】 【Table A-50】 【Table A-51】 【Table A-52】 【Table A-53】 【Table A-54】 【Table A-55】 【Table A-56】 【Table A-57】 【Table A-58】 【Table A-59】 【Table A-60】 【Table A-61】 【Table A-62】 【Table A-63】 【Table A-64】 【Table A-65】 【Table A-66】 【Table A-67】 【Table A-68】 【Table A-69】 【Table A-70】

8. The OLED material is ｎ (L Ｂ ) ｍ－ｎ The material for an OLED according to claim 1 , represented by the formula: wherein M is Ir or Pt; L Ｂ is a bidentate ligand; When M is Ir, m is 3 and n is 1, 2, or 3; When M is Pt, m is 2 and n is 1 or 2.

9. The OLED material is Ｂ is different from L ３ , IrL(L Ｂ ) ２ Or Ir(L) ２ (L Ｂ or the OLED material is represented by the formula: L and L Ｂ Pt(L)(L) may be the same or different Ｂ 9. The OLED material according to claim 8, represented by the formula:

10. When M is Ir, m is 3 and n is 1 or 2; or when M is Pt, m is 2 and n is 1; L Ｂ is shown below Ｂ１ ~L Ｂ３００ 9. The material for an OLED according to claim 8, selected from the group consisting of: 【Chemistry 4】 【Chemistry 5】 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】 【Chemistry 12】 【Chemistry 13】 【Chemistry 14】

11. the OLED material is selected from the group consisting of Compound A-1 to Compound A-429,600, Compound B-1 to Compound B-429,600, Compound C-1 to Compound C-429,600, and Compound D-1 to Compound D-429,600; Compound k-x is represented by the formula Ir(L ｋｉ ) (L Ｂｊ ) ２ It is represented by: where x=300i+j−300; k is A, B, C, or D; i is an integer from 1 to 1432, and j is an integer from 1 to 300; L Ｂ１ ~L Ｂ３００ The material for an OLED according to claim 7 , wherein: 【Chemistry 15】 【Chemistry 16】 【Chemistry 17】 【Chemistry 18】 【Chemistry 19】 【Chemistry 20】 【Chemistry 21】 【Chemical 22】 【Chemistry 23】 【Chemistry 24】 【Chemistry 25】

12. An organic layer comprising a compound containing a ligand L represented by the following formula: 【Chemistry 26】 (In the formula, R １ and R ６ represents mono-, di-, tri-, or tetra-substitution, or represents no substitution; R ２ represents mono-, di-, or tri-substitution, or represents unsubstitution; R １ , R ２ , R ３ , R ４ , R ４ , R ５ , R ６ , R ７ , and R ８ are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , and R ８ any adjacent substituents of may be joined or fused to form a ring; R ３ , R ４ , and R ５ at least one of is not hydrogen; a is an integer from 0 to 10; (i) When a is 0, R ７ , R ８ and R adjacent to ring B ２ (ii) when a is 1 to 10, at least one of R ２ and R adjacent to ring C ６ at least one of is not hydrogen; said ligand L is coordinated to a metal M having an atomic weight of more than 40; The ligand L may be combined with other ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand.

13. 13. The organic layer of claim 12, wherein the organic layer further comprises a host, the host comprising at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.

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