Organic electroluminescent materials and devices

Abstract

To provide organic luminescent compounds and composition and their various uses including as emitters in devices such as organic light emitting diodes and related consumer products.SOLUTION: Provided are multicyclic organic luminescent compounds having a ligand represented by the formula in the figure. Also provided are OLEDs and related consumer products that contain an organic layer having these organic luminescent compounds.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 62 / 880,389, filed July 30, 2019, the disclosure of which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to compounds and compositions and their various uses, including as light emitters in devices such as organic light emitting diodes and related consumer products. [Background technology]

[0003] Optoelectronic devices that utilize organic materials are becoming increasingly desirable for a variety of reasons. Because many of the materials used to fabricate such devices are relatively inexpensive, organic optoelectronic devices have the potential for cost advantages over inorganic devices. In addition, the inherent properties of organic materials, such as flexibility, may make them 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, organic materials may have performance advantages over conventional materials.

[0004] OLEDs utilize thin organic films that emit light when a voltage is applied across the device, and are becoming an increasingly interesting technology for use in applications such as flat panel displays, lighting, and backlighting.

[0005] One application of phosphorescent emissive molecules is full-color displays. Industry standards for such displays require pixels adapted to emit specific colors, referred to as "saturated" colors. In particular, these standards require saturated red, green, and blue pixels. Alternatively, OLEDs can be designed to emit white light. Conventionally, liquid crystal display emission from a white backlight is filtered with absorption filters to produce red, green, and blue emission. Similar techniques can be used with OLEDs. White OLEDs can be either single-emissive-layer (EML) devices or stack structures. Color can be measured using CIE coordinates, which are well known in the art. Summary of the Invention

[0006] In one aspect, the present disclosure provides compounds comprising a ligand LA of formula I shown below: [ka] wherein X1 to X4 are each independently C or N; X1a to X4a are each independently C or N; at least two of X1 to X4 are C; the X1 to X4 bonded to ring A is C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; C is a fused ring structure containing three or more fused heterocyclic or carbocyclic rings; R1, R2, and R3 each represent zero, mono, or up to the maximum number of substitutions allowed on the associated ring; and each R1, R2, and R3 are independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and any two substituents can be bonded to or fused with each other to form a ring.

[0007] In another aspect, the present disclosure provides a composition comprising a ligand L A of formula I described herein. The composition can also comprise a ligand L A together with other ligands, preferably selected from those described herein, although these other ligands can also be selected from ligands known in the art.

[0008] In yet another aspect, the present disclosure provides an OLED having an organic layer comprising a ligand L A of Formula I described herein. The OLED having the organic layer can also comprise a ligand L A together with other ligands preferably selected from those described herein, although these other ligands can also be selected from ligands known in the art.

[0009] In yet another aspect, the present disclosure provides a consumer product comprising an OLED having an organic layer comprising a ligand L A of Formula I described herein. The consumer product comprising an OLED having said organic layer can also comprise a ligand L A together with other ligands preferably selected from the ligands described herein, although these other ligands can also be selected from ligands known in the art. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 shows an organic light-emitting device.

[0011] [Figure 2] FIG. 2 shows an inverted organic light-emitting device that does not have a separate electron transport layer.

[0012] [Figure 3] FIG. 3 shows the transition dipole moment of the compound Ir(LB26)2(LA3-1-1) of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] A. Terminology Unless otherwise stated, the following terms used herein are defined as follows:

[0014] As used herein, the term "organic" includes polymeric 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 "small molecules" can actually be quite large. Small molecules can contain repeating units in some circumstances. For example, using a long-chain alkyl group as a substituent does not remove a molecule from the "small molecule" class. Small molecules can be incorporated into polymers, for example, as pendant groups on a polymer backbone or as part of the backbone. Small molecules can also serve as the core moiety of dendrimers, which consist of a series of chemical shells built on the core moiety. The core moiety of a dendrimer can be a fluorescent or phosphorescent small molecule emitter. Dendrimers can be "small molecules," and all dendrimers currently used in the field of OLEDs are considered to be small molecules.

[0015] As used herein, "top" means furthest from the substrate, while "bottom" means closest to the substrate. When a first layer is described as "disposed over" a second layer, the first layer is disposed further 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 may be various organic layers in between.

[0016] As used herein, "solution processable" means capable of being dissolved, dispersed or transported in and / or deposited from a liquid medium, either in the form of a solution or suspension.

[0017] A ligand may be referred to as "photoactive" if it is considered to directly contribute to the photoactive properties of the emissive material. A ligand may be referred to as "ancillary" if it is considered not to contribute to the photoactive properties of the emissive material, although the ancillary ligand may modify the properties of the photoactive ligand.

[0018] As used herein, and as generally understood by those skilled in the art, a first "highest occupied molecular orbital" (HOMO) or "lowest unoccupied molecular orbital" (LUMO) energy level is "greater than" or "higher than" a second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Because ionization potentials (IPs) are measured as negative energies relative to the vacuum level, a higher HOMO energy level corresponds to an IP with a smaller absolute value (a less negative IP). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) with a smaller absolute value (a less negative EA). On 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 closer to the top of such a diagram than a "lower" HOMO or LUMO energy level.

[0019] As used herein, and as generally understood by those skilled in the art, a first work function is "greater than" or "higher than" a second work function if the first work function has a higher absolute value. Because work functions are generally measured as negative numbers relative to vacuum level, this means that a "higher" work function is more negative. On a conventional energy level diagram, with the vacuum level at the top, a "higher" work function is illustrated as being farther away from the vacuum level in the downward direction. Thus, the definitions of HOMO and LUMO energy levels follow a different convention than work functions.

[0020] The terms "halo," "halogen," and "halide" are used interchangeably and refer to fluorine, chlorine, bromine, and iodine.

[0021] The term "acyl" refers to a substituted carbonyl group (C(O)--Rs).

[0022] The term "ester" refers to a substituted oxycarbonyl (-OC(O)-Rs or -C(O)-O-Rs) group.

[0023] The term "ether" refers to the group --OR.sub.s.

[0024] The terms "sulfanyl" or "thioether" are used interchangeably and refer to the group --SR.sub.s.

[0025] The term "sulfinyl" refers to the group -S(O)-Rs.

[0026] The term "sulfonyl" refers to the group -SO2-Rs.

[0027] The term "phosphino" refers to the group -P(Rs)3, where each Rs can be the same or different.

[0028] The term "silyl" refers to the group -Si(Rs)3, where each Rs can be the same or different.

[0029] The term "boryl" refers to the group -B(Rs)2, or its Lewis adduct -B(Rs)3, where Rs can be the same or different.

[0030] In each of the above, Rs can be hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and combinations thereof. Preferred Rs are selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.

[0031] The term "alkyl" refers to and includes both straight-chain and branched-chain alkyl groups. Preferred alkyl groups contain from 1 to 15 carbon atoms and include 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. Additionally, the alkyl groups may be optionally substituted.

[0032] The term "cycloalkyl" refers to and includes monocyclic, polycyclic, and spiroalkyl groups. Preferred cycloalkyl groups contain 3 to 12 ring carbon atoms and include cyclopropyl, cyclopentyl, cyclohexyl, bicyclo[3.1.1]heptyl, spiro[4.5]decyl, spiro[5.5]undecyl, adamantyl, and the like. Furthermore, the cycloalkyl groups may be optionally substituted.

[0033] The terms "heteroalkyl" or "heterocycloalkyl" refer to an alkyl or cycloalkyl group, respectively, having at least one carbon atom replaced by a heteroatom. Optionally, the at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably O, S, or N. Furthermore, the heteroalkyl or heterocycloalkyl group may be optionally substituted.

[0034] The term "alkenyl" refers to and includes both straight-chain and branched-chain alkene groups. An alkenyl group is essentially an alkyl group containing at least one carbon-carbon double bond in the alkyl chain. A cycloalkenyl group is essentially a cycloalkyl group containing at least one carbon-carbon double bond in the cycloalkyl ring. As used herein, the term "heteroalkenyl" refers to an alkenyl group having at least one carbon atom replaced by a heteroatom. Optionally, the at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably O, S, or N. Preferred alkenyl, cycloalkenyl, or heteroalkenyl groups are those containing 2 to 15 carbon atoms. Furthermore, the alkenyl, cycloalkenyl, or heteroalkenyl group may be optionally substituted.

[0035] The term "alkynyl" refers to and includes both straight-chain and branched-chain alkyne groups. Alkynyl groups are essentially alkyl groups containing at least one carbon-carbon triple bond in the alkyl chain. Preferred alkynyl groups are those containing 2 to 15 carbon atoms. Furthermore, the alkynyl groups may be optionally substituted.

[0036] The terms "aralkyl" and "arylalkyl" are used interchangeably and refer to an alkyl group substituted with an aryl group. In addition, said aralkyl group may be optionally substituted.

[0037] The term "heterocyclic group" refers to and includes aromatic and non-aromatic cyclic groups containing at least one heteroatom. Optionally, the at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably O, S, or N. Heteroaromatic cyclic groups may be used interchangeably with heteroaryl. Preferred heteroaromatic cyclic groups contain 3 to 7 ring atoms and include at least one heteroatom, including cyclic amines such as morpholino, piperidino, and pyrrolidino, and cyclic ethers / thioethers such as tetrahydrofuran, tetrahydropyran, and tetrahydrothiophene. Furthermore, the heterocyclic groups may be optionally substituted.

[0038] The term "aryl" refers to and includes both monocyclic aromatic hydrocarbyl groups and polycyclic aromatic ring systems. A polycyclic ring can have two or more rings in which two carbon atoms are shared between two adjacent rings (the rings are "fused"), at least one of which is an aromatic hydrocarbyl group, and the other rings can be, for example, a cycloalkyl, cycloalkenyl, aryl, heterocyclic, and / or heteroaryl. Preferred aryl groups contain 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, and more preferably 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, and are preferably phenyl, biphenyl, triphenyl, triphenylene, fluorene, and naphthalene. Furthermore, the aryl group may be optionally substituted.

[0039] The term "heteroaryl" refers to and includes both monocyclic aromatic groups and polycyclic aromatic ring systems containing at least one heteroatom. Heteroatoms include, but are not limited to, O, S, N, P, B, Si, and Se. In many instances, O, S, or N are preferred heteroatoms. Heteromonocyclic aromatic systems are preferably monocyclic rings having 5 or 6 ring atoms, and the rings can have 1 to 6 heteroatoms. Heteropolycyclic ring systems can have two or more rings in which two atoms are common to two adjacent rings (the rings are "fused"), and at least one of the rings is heteroaryl; for example, the other rings can be cycloalkyl, cycloalkenyl, aryl, heterocyclic, and / or heteroaryl. Heteropolycyclic aromatic ring systems can have 1 to 6 heteroatoms per ring of the polycyclic aromatic ring system. Preferred heteroaryl groups are those containing 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, and more preferably 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, benziso ... Examples of heteroaryl groups include benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine, and preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborine, 1,3-azaborine, 1,4-azaborine, borazine, and their aza analogs. Furthermore, the heteroaryl group may be optionally substituted.

[0040] Of the aryl and heteroaryl groups listed above, triphenylene, naphthalene, anthracene, dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, pyrazine, pyrimidine, triazine, and benzimidazole groups, and their respective aza analogues, are of particular interest.

[0041] As used herein, the terms alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aralkyl, heterocyclic, aryl, and heteroaryl are independently unsubstituted or independently substituted with one or more common substituents.

[0042] In many instances, the typical substituents are selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, boryl, and combinations thereof.

[0043] In some instances, preferred general substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, boryl, and combinations thereof.

[0044] In some instances, more preferred common substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, alkoxy, aryloxy, amino, silyl, boryl, aryl, heteroaryl, sulfanyl, and combinations thereof.

[0045] In still other instances, the most preferred general substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.

[0046] The terms "substituted" and "substituted" refer to a substituent other than H attached to the relevant position (e.g., carbon or nitrogen). For example, if R represents mono-substitution, one R must be other than H (i.e., substituted). Similarly, if R represents di-substitution, two of R must be other than H. Similarly, if R represents zero or no substitution, R can be hydrogen at an available valence of a ring atom, as in the case of carbon atoms in benzene and nitrogen atoms in pyrrole, or simply nothing in the case of a ring atom with a fully satisfied valence (e.g., nitrogen in pyridine). The maximum number of substitutions possible in a ring structure depends on the total number of available valences of the ring atoms.

[0047] As used herein, "combinations thereof" refers to one or more members of the applicable list being combined to form known or chemically stable configurations that one skilled in the art can contemplate from the applicable list. For example, alkyl and deuterium can be combined to form a partially or fully deuterated alkyl group; halogen and alkyl can be combined to form a halogenated alkyl substituent; halogen, alkyl, and aryl can be combined to form a halogenated arylalkyl. In one example, the term "substituted" includes combinations of 2 to 4 of the listed groups. In another example, the term "substituted" includes combinations of 2 to 3 groups. In yet another example, the term "substituted" includes combinations of 2 groups. Preferred combinations of substituents are those containing up to 50 atoms that are not hydrogen or deuterium, or those containing up to 40 atoms that are not hydrogen or deuterium, or those containing up to 30 atoms that are not hydrogen or deuterium. In many examples, preferred combinations of substituents include up to 20 atoms that are not hydrogen or deuterium.

[0048] The designation "aza" in the fragments described herein, such as aza-dibenzofuran, aza-dibenzothiophene, etc., means that one or more of the C—H groups in each aromatic ring can be replaced by a nitrogen atom; for example, but not by way of limitation, azatriphenylene encompasses both dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. Those skilled 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.

[0049] As used herein, "deuterium" refers to an isotope of hydrogen. Deuterated compounds can be readily prepared using methods known in the art. For example, U.S. Pat. No. 8,557,400, International Publication No. WO 2006 / 095951, and U.S. Patent Application Publication No. 2011 / 0037057, the entire contents of which are incorporated by reference, describe the preparation of deuterium-substituted organometallic complexes. Further reference is made to Tetrahedron 2015, 71, 1425-30 (Ming Yan et al.) and Angew. Chem. Int. Ed. (Reviews) 2007, 46, 7744-65 (Atzrodt et al.), the entire contents of which are incorporated by reference, which describe efficient routes for deuteration of methylene hydrogens in benzylamines and substitution of aromatic ring hydrogens with deuterium, respectively.

[0050] It is understood that when a molecular fragment is described as being a substituent or as being attached to another moiety, the name may be described as being the fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuryl) or the entire molecule (e.g., benzene, naphthalene, dibenzofuran). Different designations of substituents or attached fragments are considered equivalent herein.

[0051] In some instances, adjacent substituents in a pair can be optionally bonded or fused to form a ring. Preferred rings are 5-, 6-, or 7-membered carbocyclic or heterocyclic rings, including both cases where the portion of the ring formed by the pair of substituents is saturated and cases where the portion of the ring formed by the pair of substituents is unsaturated. As used herein, "adjacent" means that the two related substituents can be adjacent to each other on the same ring, or can be adjacent to each other on two rings that have the two nearest available substitutable positions, such as the 2- and 2'-positions in biphenyl and the 1- and 8-positions in naphthalene, as long as a stable fused ring system can be formed. B. Compounds of the Present Disclosure

[0052] The present disclosure provides compounds comprising a ligand LA of formula I, represented below: [ka] wherein X1-X4 are each independently C or N; X1a-X4a are each independently C or N; at least two of X1-X4 are C; the X1-X4 bonded to ring A is C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; ring C is a fused ring structure containing three or more fused heterocyclic or carbocyclic rings; R, R, and R each represent zero, one, or up to the maximum number of substitutions allowed on the associated ring; each R, R, and R are independently hydrogen or a substituent selected from the group consisting of the general substituents defined herein, and any two substituents can be bonded or fused to form a ring. The ligand L A can be complexed with a metal M. The metal M can be Os, Ir, Pd, Pt, Cu, Ag, or Au. The ligand LA can be combined with other ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand. The other ligands can be preferably selected from the ligands described herein. The other ligands can also be selected from ligands known in the art.

[0053] In some embodiments, each R A can independently be hydrogen or a substituent selected from the group of preferred general substituents defined herein.

[0054] In some embodiments, each R A can independently be hydrogen or a substituent selected from the group consisting of the more preferred general substituents defined herein.

[0055] In some embodiments, each R B can independently be hydrogen or a substituent selected from the group of preferred general substituents defined herein.

[0056] In some embodiments, each R B can independently be hydrogen or a substituent selected from the group consisting of the more preferred general substituents defined herein.

[0057] In some embodiments, each R C can independently be hydrogen or a substituent selected from the group of preferred general substituents defined herein.

[0058] In some embodiments, each R C can independently be hydrogen or a substituent selected from the group of more preferred general substituents defined herein.

[0059] In some embodiments, X1-X4 can each be C.

[0060] In some embodiments, R1 can be a partially or fully deuterated alkyl group. In some embodiments, R1 can be a CD3 group.

[0061] In some embodiments, at least one R A is a partially or fully deuterated alkyl group, hi some embodiments, at least one R A is a CD 3 group.

[0062] In some embodiments, X1a-X4a are each C. In some embodiments, at least one of X1a-X4a is N. In some embodiments, at least two of X1a-X4a are N. In some embodiments, ring A is selected from the group consisting of phenyl, pyridine, pyrimidazine, pyrazine, pyridazine, and triazine.

[0063] In some embodiments, Z can be C.

[0064] In some embodiments, ring C can comprise rings independently selected from 5-membered rings and 6-membered rings. In some embodiments, ring C can comprise two 6-membered rings and one 5-membered ring. In some embodiments, ring C can comprise three 6-membered rings and one 5-membered ring. In some embodiments, ring C can comprise two 6-membered rings and two 5-membered rings.

[0065] In some embodiments, X2 can be attached to ring A.

[0066] In some embodiments, X3 can be attached to ring A.

[0067] In some embodiments, ring A can be 2,6-disubstituted.

[0068] In one embodiment, the present disclosure provides a ligand of formula II: [ka] wherein X is selected from the group consisting of O, S, Se, NR, CRR′, and SiRR′; R and R′ are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, aryl, heteroaryl, and combinations thereof; X5 to X12 are each independently C or N; X5 to X12 that form a bond with M are C; and two R-C substituents can be bonded to or fused with each other to form a ring.

[0069] In some embodiments of Formula II, X can be O.

[0070] In some embodiments of Formula II, X5 through X12 can each be C. In some embodiments, at least one of X5 through X12 is N. In some embodiments, at least one of X9 through X12 is N. In some embodiments, X9 is N, and X5 through X8, X10 through X12 are C. In some embodiments, the maximum number of N atoms that can be bonded to each other in a ring is 2.

[0071] In some embodiments of Formula II, two R-C substituents can be bonded to each other to form a 5- or 6-membered aromatic ring, which may be further fused and substituted. In some embodiments, the 6-membered aromatic ring is selected from the group consisting of benzene, pyridine, pyrimidine, pyrazine, pyridazine, and triazine. In some embodiments, the 6-membered aromatic ring is benzene. In some embodiments of Formula II, two R-C substituents can be bonded to each other to form a substituted or unsubstituted group selected from the group consisting of furan, thiophene, pyrrole, cyclopentadiene, and benzo-variants thereof.

[0072] In some of the above embodiments, the ligand LA may be selected from the group consisting of: [ka] [ka] [ka] [ka] wherein X and Y are each independently selected from the group consisting of O, S, NR, CRR', and SiRR'; RD represents zero, mono, and up to the maximum number of substitutions allowed; and each RD is independently hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, and combinations thereof.

[0073] In some of the above embodiments, the ligand LA is defined in the first LA list having the formula LAi-NM, where i is an integer from 1 to 14, N is an integer from 1 up to 7, and M is an integer from 1 to 649; the structure of each LAi-N is defined below. [ka] [ka] [ka] [ka] wherein for each LAi-N, the substituents R1, RA, and RB are defined in Table A below as a series of M. [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] In the formula, the substituents A to Z″ are defined as follows. [ka] [ka] [ka]

[0074] In some embodiments, the present disclosure provides a compound of formula M(LA)x(LB)y(LC)z, where LA is a compound described herein, LB and LC are each bidentate ligands; x is 1, 2, or 3; y is 0, 1, or 2; z is 0, 1, or 2; and x + y + z is the oxidation state of the metal M.

[0075] In some embodiments, M(LA)x(LB)y(LC)z can be selected from the group consisting of Ir(LA), Ir(LA)(LB), Ir(LA)2(LB), Ir(LA)2(LC), and Ir(LA)(LB)(LC); wherein LA, LB, and LC are different from one another.

[0076] In some embodiments, M(LA)(LB)(LC) can be a compound of formula Pt(LA)(LB), where LA and LB can be the same or different. In some embodiments, LA and LB combine to form a tetradentate ligand.

[0077] In some embodiments of compounds of formula M(LA)x(LB)y(LC)z, LB and LC can each independently be selected from the group consisting of: [ka] [ka] wherein each Y1-Y13 is independently selected from the group consisting of carbon and nitrogen; Y' is selected from the group consisting of BRe, NRe, PRe, O, S, Se, C=O, S=O, SO2, CReRf, SiReRf, and GeReRf; Re and Rf can be fused or linked to form a ring; each Ra, Rb, Rc, and Rd can independently represent zero, mono, and up to the maximum number of substitutions allowed for that associated ring; each Ra, Rb, Rc, Rd, Re, and Rf is independently hydrogen or a substituent selected from the group consisting of the general substituents described herein; and any two adjacent substituents of Ra, Rb, Rc, and Rd can be fused or linked to form a ring or a polydentate ligand.

[0078] In some embodiments of compounds of formula M(LA)x(LB)y(LC)z, LB and LC can each independently be selected from the group consisting of: [ka] [ka] [ka]

[0079] In some embodiments of compounds of the general formula M(LA)x(LB)y(LC)z, the compound is selected from the group consisting of a compound AiNM having the formula Ir(LAi-NM)3, a compound BiNMk having the formula Ir(LAi-NM)(LBk), a compound CiNMk having the formula Ir(LAi-NM)2(LBk), a compound DiNMjI having the formula Ir(LAi-NM)(LCj-I)2, or a compound EiNMj-II having the formula Ir(LAi-NM)(LCj-II)2, where i is an integer from 1 to 14, N is an integer from 1 up to 5, M is an integer from 1 to 649, k is an integer from 1 to 264, and j is an integer from 1 to 768; and LB1 through LB264 have structures as defined in the first LB list shown below. [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] The LC is selected from a first list of LCs consisting of: [ka] LCj-I having a structure based on: [ka] wherein j is an integer from 1 to 768, and in each LCj in LCj-I and LCj-II, R1' and R2' are defined as shown in the first LC list below. [ka] [ka] [ka] [ka] [ka] [ka] [ka] In the formula, RD1 to RD192 have the following structures: [ka] [ka] [ka] [ka]

[0080] In some embodiments of a compound of formula M(LA)x(LB)y(LC)z, LB is selected from the group consisting of LB1, LB2, LB18, LB28, LB38, LB108, LB118, LB122, LB124, LB126, LB128, LB130, LB32, LB134, LB136, LB138, LB140, LB142, LB144, LB156, LB58, LB160, LB162, LB164, LB168, LB172, LB175, LB204, LB206, LB214, LB216, LB218, LB220, LB222, LB231, LB233, LB235, LB237, LB240, LB242, LB244, LB246, LB248, LB250, LB252, LB254, LB256, LB258, LB260, LB262, LB263, and LB264.

[0081] In some embodiments, LB can be selected from the group consisting of LB1, LB2, LB18, LB28, LB38, LB108, LB118, LB122, LB124, LB126, LB128, LB132, LB136, LB138, LB142, LB156, LB162, LB204, LB206, LB214, LB216, LB218, LB220, LB231, LB233, and LB237.

[0082] In some embodiments of compounds having the formula M(LA)x(LB)y(LC)z, where LA and LB are defined above, LC can be selected from a second LC list consisting of only LCj-I and LCj-II, whose corresponding R1 and R2 are defined to be selected from the following structures: RD1, RD3, RD4, RD5, RD9, RD10, RD17, RD18, RD20, RD22, RD37, RD40, RD41, RD42, RD 43, RD48, RD49, RD50, RD54, RD55, RD58, RD59, RD78, RD79, RD81, RD87, RD88, RD89, RD93, RD116, RD117, RD118, RD119, RD120, RD133, RD134, RD135, RD136, RD143, RD144, RD145, RD146, RD147, RD149, RD151, RD154, RD155, RD161, RD175, and RD190.

[0083] In some embodiments, LC can be selected from a third LC list consisting only of LCj-I and LCj-II, whose corresponding R1 and R2 are defined as selected from the following structures: RD1, RD3, RD4, RD5, RD9, RD17, RD22, RD43, RD50, RD78, RD116, RD118, RD133, RD134, RD135, RD136, RD143, RD144, RD145, RD146, RD149, RD151, RD154, RD155, and RD190.

[0084] In some embodiments of compounds having the formula M(LA)x(LB)y(LC)z, where LA and LB are defined above, LC can be selected from a fourth LC list consisting of: [ka] [ka]

[0085] In some embodiments of a compound having the formula M(LA)x(LB)y(LC)z, L A is selected from the group consisting of structures defined in the first L A list described above, L B is selected from the group consisting of structures defined in the first L B list described above, and L C is selected from the group consisting of structures defined in the first L C list described above.

[0086] In some embodiments, the compound is selected from the group consisting of a compound AiNM having the formula Ir(LAi-NM)3, a compound BiNMk having the formula Ir(LAi-NM)(LBk), a compound CiNMk having the formula Ir(LAi-NM)2(LBk), a compound DiNMjI having the formula Ir(LAi-NM)(LCj-I)2, or a compound EiNMj-II having the formula Ir(LAi-NM)(LCj-II)2, wherein i is an integer from 1 to 14, N is an integer from 1 up to 5, M is an integer from 1 to 649, k is an integer from 1 to 264, and j is an integer from 1 to 768; each LAi-NM, LBk, LCj-I, and LCj-II is defined above.

[0087] In some embodiments, the compound is selected from the list of compounds consisting of: [ka] [ka] [ka] [ka] [ka] [ka] C. OLEDs and Devices of the Present Disclosure

[0088] In another aspect, the present disclosure also provides an OLED device that includes a first organic layer containing a compound disclosed in the Compounds section of this disclosure.

[0089] In some embodiments, the OLED comprises an organic layer comprising a compound of Formula I shown below: [ka] wherein X1-X4 are each independently C or N; X1a-X4a are each independently C or N; at least two of X1-X4 are C; the X1-X4 bonded to ring A is C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; C is a fused ring structure containing three or more fused heterocycles or carbocycles; R, R, and R each represent zero, one, or up to the maximum number of substitutions allowed on the associated ring; each R, R, and R are independently hydrogen or a substituent selected from the group consisting of the general substituents defined herein and combinations thereof, and any two substituents can be bonded or fused to form a ring. The ligand L A can be complexed with a metal M. The metal M can be Os, Ir, Pd, Pt, Cu, Ag, or Au. The ligand LA can be combined with other ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand. The other ligands can be preferably selected from the ligands described herein. The other ligands can also be selected from ligands known in the art.

[0090] In some embodiments, the OLED comprises an organic layer comprising a compound of Formula II shown below: [ka] wherein X is selected from the group consisting of O, S, Se, NR, CRR′, and SiRR′; R and R′ are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, aryl, heteroaryl, and combinations thereof; X5 to X12 are each independently C or N; X5 to X12 that form a bond with M are C; the maximum number of N atoms that can be bonded to each other is 2; and two R-C substituents can be bonded to each other or fused to form a ring.

[0091] In some embodiments, the OLED can include an organic layer that includes the LAx-N compounds described herein.

[0092] In some embodiments, the OLED can include an organic layer comprising a compound of the formula M(LA)x(LB)y(LC)z, where LA is a compound described herein, LB and LC are each bidentate ligands; x is 1, 2, or 3; y is 0, 1, or 2; z is 0, 1, or 2; and x + y + z is the oxidation state of the metal M.

[0093] In some embodiments, the OLED can include an organic layer comprising a compound of M(LA)(LB)(LC), which can have the formula Ir(LA), Ir(LA)(LB), or Ir(LA)(LC), where LA, LB, and LC can have structures described herein. In some embodiments, LB can be a compound selected from the group consisting of LB1-LB263 described herein. In some embodiments, LC can be selected from the group consisting of structures defined in the LC list described herein.

[0094] In some embodiments, the OLED can include a compound selected from the group consisting of Ir(LA), Ir(LA)(LB), Ir(LA)(LB), Ir(LA)(LC), and Ir(LA)(LB)(LC); where LA, LB, and LC are different from one another, and each can preferably be a ligand described herein.

[0095] In some embodiments, the OLED can include an organic layer having a compound of M(LA)(LB)(LC), which can be a compound of formula Pt(LA)(LB), where LA and LB can be the same or different. In some embodiments, LA and LB combine to form a tetradentate ligand.

[0096] In some embodiments, the organic layer can be an emissive layer, and the compounds described herein can be an emissive or non-emissive dopant.

[0097] In some embodiments, the organic layer can further include a host, the host including a triphenylene, including a benzo-fused thiophene or a benzo-fused furan, and any substituents in the host can be independently selected from the group consisting of CnH2n+1, OCnH2n+1, OAr1, N(CnH2n+1)2, N(Ar1)(Ar2), CH=CH-CnH2n+1, C≡C-CnH2n+1, Ar1, Ar1-Ar2, and CnH2n-Ar1, or can be unsubstituted, where n is 1 to 10, and Ar1 and Ar2 can be independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof.

[0098] In some embodiments, the organic layer can further include a host, wherein the host comprises at least one chemical group selected from the group consisting of triphenylene, carbazole, indolocarbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene, aza-triphenylene, aza-carbazole, aza-indolocarbazole, aza-dibenzothiophene, aza-dibenzofuran, aza-dibenzoselenophene, and aza-(5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene).

[0099] In some embodiments, the host may be selected from the group of hosts selected from the group consisting of: [ka] [ka] [ka]

[0100] In some embodiments, the organic layer can further comprise a host, wherein the host comprises a metal complex.

[0101] In some embodiments, the compound described herein can be a sensitizer, and the device can further include an acceptor, and the acceptor can be selected from a fluorescent emitter, a delayed fluorescent emitter, and a combination thereof.

[0102] In yet another embodiment, the OLED of the present disclosure can also include a light-emitting region comprising a compound disclosed in the Compounds section of this disclosure.

[0103] In some embodiments, the emissive region can include a compound comprising a ligand LA of Formula I. [ka] wherein X1 to X4 are each independently C or N; X1a to X4a are each independently C or N; at least two of X1 to X4 are C; the X1 to X4 bonded to ring A is C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; C is a fused ring structure containing three or more fused heterocycles or carbocycles; R, R, and R each represent zero, one, or up to the maximum number of substitutions allowed on the associated ring; and each R, R, and R are independently hydrogen or a substituent selected from the group consisting of the general substituents defined herein, and any two substituents can be bonded to or fused to each other to form a ring.

[0104] In yet another aspect, the present disclosure also provides a consumer product comprising an OLED having an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a compound disclosed in the Compounds section of this disclosure.

[0105] In some embodiments, the consumer product includes an organic light emitting device (OLED) having an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer can include a compound including a ligand LA of Formula I. [ka] wherein X1 to X4 are each independently C or N; X1a to X4a are each independently C or N; at least two of X1 to X4 are C; the X1 to X4 bonded to ring A is C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; C is a fused ring structure containing three or more fused heterocycles or carbocycles; R, R, and R each represent zero, one, or up to the maximum number of substitutions allowed on the associated ring; and each R, R, and R are independently hydrogen or a substituent selected from the group consisting of the general substituents defined herein, and any two substituents can be bonded to or fused to each other to form a ring.

[0106] In some embodiments, the consumer product can be one of a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for indoor or outdoor illumination and / or signaling, a head-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a mobile phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay less than 2 inches in diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall including multiple displays aligned together, a theater or stadium screen, a light therapy device, and a sign.

[0107] Generally, an OLED comprises 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 migrate to the oppositely charged electrode, respectively. When an electron and hole localize on the same molecule, an "exciton," a localized electron-hole pair with an excited energy state, is formed. Light is emitted via a photoemissive mechanism when the exciton relaxes. In some cases, the exciton may be localized on an excimer or exciplex. Non-radiative mechanisms, such as thermal relaxation, can also occur but are generally considered undesirable.

[0108] Some OLED materials and configurations are described in US Pat. Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated by reference in their entireties.

[0109] Early OLEDs used emissive molecules that emitted light from their singlet state ("fluorescence"), as disclosed, for example, in U.S. Patent No. 4,769,292, which is incorporated by reference in its entirety. Fluorescence emission typically occurs in a time frame of less than 10 nanoseconds.

[0110] More recently, OLEDs have been demonstrated that have emissive materials that emit light from triplet states ("phosphorescence"). Baldo et al., "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices," Nature, Vol. 395, No. 151-154, 1998; ("Baldo-I") and Baldo et al., "Very high-efficiency green organic light emitting devices based on electrophosphorescence," Appl. Phys. Lett., Vol. 75, No. 3, 4-6 (1999) ("Baldo-II"), which are incorporated by reference in their entireties. Phosphorescence is described in further detail in U.S. Pat. No. 7,279,704, columns 5-6, which are incorporated by reference.

[0111] FIG. 1 shows an organic light-emitting device 100. The drawing 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, an emissive 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 compound cathode having a first conductive layer 162 and a second conductive layer 164. Device 100 may be fabricated by depositing the layers described, in order. The properties and functions of these various layers, as well as example materials, are described in further detail in U.S. Pat. No. 7,279,704, cols. 6-10, which are incorporated by reference.

[0112] Further examples are available for each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated by reference 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 in its entirety. Examples of emissive and host materials are disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated by reference 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 in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entireties, disclose examples of cathodes, including composite cathodes with a thin layer of metal, such as Mg:Ag, with an overlying transparent, conductive, sputter-deposited ITO layer. The theory and use of blocking layers 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 by reference in their entireties. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated by reference in its entirety. A description of protective layers can be found in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated by reference in its entirety.

[0113] FIG. 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole-transport layer 225, and an anode 230. Device 200 can be fabricated by depositing the layers described, in order. Because the most common OLED configuration has the cathode disposed above the anode, and device 200 has cathode 215 disposed below anode 230, device 200 can be referred to as an "inverted" OLED. Materials similar to those described with respect to device 100 may be used in the corresponding layers of device 200. FIG. 2 provides an example of how some layers can be omitted from the structure of device 100.

[0114] The simple layer structures illustrated in Figures 1 and 2 are provided as non-limiting examples, and it is understood that embodiments of the present disclosure can be used in conjunction 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 may be achieved by combining the various layers described in various ways, or layers may 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. While many of the examples provided herein describe various layers as including a single material, it is understood that combinations of materials, such as a mixture of a host and a dopant, or more generally, a mixture, may be used. Layers may also have various sublayers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole-transport layer 225 transports holes and injects holes into emissive 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 a cathode and an anode. The organic layer may include a single layer, or may further include multiple layers of different organic materials, such as those described with respect to Figures 1 and 2.

[0115] Structures and materials not specifically described may also be used, such as OLEDs (PLEDs) composed of polymeric materials, such as those disclosed in U.S. Pat. No. 5,247,190 to Friend et al., which is incorporated by reference in its entirety. As a further example, an OLED having a single organic layer may be used. OLEDs may be stacked, for example, as described in U.S. Pat. No. 5,707,745 to Forrest et al., which is incorporated by reference in its entirety. OLED structures may deviate from the simple layered structures illustrated in FIGS. 1 and 2. For example, the substrate may include angled reflective surfaces to improve outcoupling, such as the mesa structure described in U.S. Pat. No. 6,091,195 to Forrest et al. and / or the recessed structure described in U.S. Pat. No. 5,834,893 to Bulovic et al., which are incorporated by reference in their entirety.

[0116] Unless otherwise specified, any of the layers of the various embodiments can be deposited by any suitable method. For organic layers, preferred methods include deposition by thermal evaporation, such as those described in U.S. Pat. Nos. 6,013,982 and 6,087,196, which are incorporated by reference in their entireties; inkjet deposition; organic vapor phase deposition (OVPD), such as that described in U.S. Pat. No. 6,337,102 to Forrest et al., which is incorporated by reference in its entirety; and organic vapor jet printing (OVJP), such as that described in U.S. Pat. No. 7,431,968, which is incorporated 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 patterning through a mask, such as those described in U.S. Patent Nos. 6,294,398 and 6,468,819, which are incorporated by reference in their entireties, deposition via cold welding, and patterning associated with some deposition methods, such as inkjet and organic vapor jet printing (OVJP). Other methods may also be used. The material to be deposited may be modified to be compatible with a particular deposition method. For example, substituents such as alkyl and aryl groups, branched or unbranched, preferably containing at least three carbons, may be used in small molecules to enhance their ability to undergo solution processing. Substituents with 20 or more carbons may be used, with 3 to 20 carbons being a preferred range. Materials with asymmetric structures may have better solution processability than those with symmetric structures, because asymmetric materials may be less prone to recrystallization. Dendrimer substituents may be used to enhance the ability of small molecules to undergo solution processing.

[0117] Devices fabricated according to embodiments of the present disclosure 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 the environment, including moisture, vapors, and / or gases. The barrier layer may be deposited over, under, or adjacent to the substrate, the electrode, or any other portion of the device, including the edges. The barrier layer may include a single layer or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may 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. Pat. No. 7,968,146 and PCT Patent Application Nos. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are incorporated herein by reference in their entireties. To be considered a "mixture," the polymeric and non-polymeric materials comprising the barrier layer should be deposited under the same reaction conditions and / or simultaneously. The weight ratio of polymeric to non-polymeric materials can be in the range of 95:5 to 5:95. The polymeric and non-polymeric materials can be made from the same precursor materials. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric silicon and inorganic silicon.

[0118] Devices made according to embodiments of the present disclosure 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), and the like, which can be utilized by end-user product manufacturers. Such electronic component modules can optionally include drive electronics and / or power sources. Devices made according to embodiments of the present disclosure can be incorporated into a wide variety of consumer products having one or more electronic component modules (or units) incorporated therein. Consumer products are disclosed that include OLEDs that include compounds of the present disclosure in the organic layer of the OLED. Such consumer products include any type of product that includes one or more light sources and / or one or more visual displays of some kind. Some examples of such consumer products include flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for indoor or outdoor illumination and / or signaling, head-up displays, fully or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable 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 aligned together, theater or stadium screens, light therapy devices, and signage. A variety of control mechanisms, including passive matrix and active matrix, can be used to control devices fabricated according to the present disclosure. Many of the devices are intended for use within a temperature range comfortable to humans, such as 18°C ​​to 30°C, and more preferably room temperature (20-25°C), but can also be used outside this temperature range, e.g., between -40°C and +80°C.

[0119] Further details regarding OLEDs and the definitions set forth above can be found in US Pat. No. 7,279,704, which is incorporated by reference in its entirety.

[0120] 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.

[0121] In some embodiments, the OLED has one or more properties selected from the group consisting of flexible, rollable, foldable, stretchable, and bendable. In some embodiments, the OLED is transparent or translucent. In some embodiments, the OLED further comprises a layer comprising carbon nanotubes.

[0122] In some embodiments, the OLED further comprises a layer comprising a delayed fluorescent emitter. In some embodiments, the OLED comprises an RGB pixel array or a white and color filter pixel array. In some embodiments, the OLED is a mobile device, a handheld device, or a wearable device. In some embodiments, the OLED is a display panel having a diagonal of less than 10 inches or an area of ​​less than 50 square inches. In some embodiments, the OLED is a display panel having a diagonal of at least 10 inches or an area of ​​at least 50 square inches. In some embodiments, the OLED is a lighting panel.

[0123] In some embodiments, the compound can be an emissive dopant. In some embodiments, the compound can generate luminescence via phosphorescence, fluorescence, thermally activated delayed fluorescence (TADF) (also known as E-type delayed fluorescence; see, e.g., U.S. Application No. 15 / 700,352, incorporated by reference in its entirety), triplet-triplet annihilation, or a combination of these processes. In some embodiments, the emissive dopant can be a racemic mixture or enriched in one enantiomer. In some embodiments, the compound can be homoleptic (each ligand is the same). In some embodiments, the compound can be heteroleptic (at least one ligand is different from the others). When more than one ligand is present that coordinates to the metal, in some embodiments, the ligands can all be the same. In some other embodiments, at least one ligand is different from the other ligands. In some embodiments, all of the ligands can be different from each other. This is true even in embodiments where a ligand coordinated to a metal can combine with other ligands coordinated to the metal to form a tridentate, tetradentate, pentadentate, or hexadentate ligand. Thus, when the coordinating ligands are bonded to one another, in some embodiments, all of the ligands can be identical, while in some other embodiments, at least one of the bonded ligands can be different from the other ligands.

[0124] In some embodiments, the compound can be used as a phosphorescent sensitizer in an OLED, where one or more layers in the OLED contain an acceptor in the form of one or more fluorescent and / or delayed fluorescent emitters. In some embodiments, the compound can be used as one component of an exciplex used as a sensitizer. As a phosphorescent sensitizer, the compound must be capable of energy transfer to the acceptor, which can emit energy or further transfer energy to the final emitter. The acceptor concentration can range from 0.001% to 100%. The acceptor can be in the same layer as the phosphorescent sensitizer or in one or more different layers. In some embodiments, the acceptor is a TADF emitter. In some embodiments, the acceptor is a fluorescent emitter. In some embodiments, the emission can come from any or all of the sensitizer, the acceptor, and the final emitter.

[0125] According to another aspect, compositions comprising the compounds described herein are also disclosed.

[0126] 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, while in other embodiments, the compound can be a non-emissive dopant.

[0127] In yet another aspect of the present disclosure, there is provided a composition comprising the novel compounds disclosed herein. The composition may also comprise one or more components selected from the group consisting of a solvent, a host, a hole injection material, a hole transport material, an electron blocking material, a hole blocking material, and an electron transport material disclosed herein.

[0128] The present disclosure encompasses any chemical structure comprising the novel compounds of the present disclosure, or monovalent or polyvalent variants thereof. In other words, the compounds of the present invention, or monovalent or polyvalent variants thereof, can be part of a larger chemical structure. Such chemical structures can be selected from the group consisting of monomers, polymers, macromolecules, and supramolecules (also known as supermolecules). As used herein, a "monovalent variant of a compound" refers to a moiety that is identical to the compound except that one hydrogen has been removed and replaced with a bond to the remainder of the chemical structure. As used herein, a "polyvalent variant of a compound" refers to a moiety that is identical to the compound except that more than one hydrogen has been removed and replaced with a bond to the remainder of the chemical structure. In the example of a supramolecule, the compounds of the present invention can also be incorporated into the supramolecular complex without a covalent bond. D. Combinations of Compounds of the Present Disclosure with Other Materials

[0129] 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 conjunction 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 may be useful in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that may be useful in combination. a) Conductive (electrically conductive) dopants:

[0130] The charge transport layer is doped with a conductive dopant to significantly change the density of charge carriers and thereby its conductivity. The conductivity can be increased by generating charge carriers in the matrix material or, depending on the type of dopant, a change 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 n-type conductive dopants are used in the electron transport layer.

[0131] Non-limiting examples of conductive dopants that can be used in OLEDs in combination with the materials disclosed herein are illustrated below, along with references that disclose these materials. EP01617493, EP01968131, EP2020694, EP2684932, US20050139810, US20070160905, US20090167167, US2010288362, WO06081780, WO2009003455, WO2009008277, WO2009011327, WO2014009310, US2007252140, US2015060804, US20150123047, and US2012146012 [ka] [ka] b) HIL / HTL:

[0132] The hole injection / transport material used in the present disclosure is not particularly limited, and any compound may be used as long as it is a compound typically used as a hole injection / transport material. Examples of such materials include, but are not limited to, phthalocyanine or porphyrin derivatives, aromatic amine derivatives, indolocarbazole derivatives, polymers containing fluorocarbons, polymers having conductive dopants, conductive polymers such as PEDOT / PSS, self-assembly monomers derived from compounds such as phosphonic acid and silane derivatives, metal oxide derivatives such as MoOx, p-type semiconductor organic compounds such as 1,4,5,8,9,12-hexaazatriphenylene hexacarbonitrile, metal complexes, and crosslinkable compounds.

[0133] Examples of aromatic amine derivatives used in the HIL or HTL include, but are not limited to, the following general structures: [ka]

[0134] Each of Ar1 to Ar9 is a group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene; 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, and aromatic heterocyclic compounds such as 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 aromatic hydrocarbon ring groups and aromatic heterocyclic groups, which may be the same or different groups and which are 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 Ar can be unsubstituted or substituted with a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0135] In one embodiment, Ar1 to Ar9 are [ka] wherein k is an integer from 1 to 20; X101 to X108 are C (including CH) or N; Z101 is NAr1, O, or S; and Ar1 has the same groups as defined above.

[0136] Examples of metal complexes used in the HIL or HTL include, but are not limited to, those of the following general formula: [ka] wherein Met is a metal that may have an atomic weight greater than 40; (Y101-Y102) is a bidentate ligand, where Y101 and Y102 are independently selected from C, N, O, P, and S; L101 is an ancillary ligand; k' is an integer value from 1 to the maximum number of ligands that may be bound to the metal; and k'+k'' is the maximum number of ligands that may be bound to the metal.

[0137] In one embodiment, (Y101-Y102) is a 2-phenylpyridine derivative. In another embodiment, (Y101-Y102) is a carbene ligand. In another embodiment, Met is selected from Ir, Pt, Os, and Zn. In a further embodiment, the metal complex has a minimum oxidation potential in solution of less than about 0.6 V relative to the Fc / Fc couple.

[0138] Non-limiting examples of HIL and HTL materials that can be used in OLEDs in combination with the materials disclosed herein are exemplified below along with references that disclose 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 [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] c) EBL:

[0139] An electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons that leave the emissive layer. The presence of such a blocking layer in a device can result in significantly higher efficiency and / or longer lifetime compared to a similar device lacking a blocking layer. Blocking layers can also be used to confine emission to a desired region of an OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or a 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 a 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 used as one of the hosts described below. d) Host:

[0140] 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. The host material is not particularly limited, and any metal complex or organic compound can be used as long as the triplet energy of the host is higher than that of the dopant. Any host material can be used with any dopant as long as the triplet criterion is met.

[0141] Examples of metal complexes used as host materials preferably have the following general formula: [ka] wherein Met is a metal; (Y103-Y104) is a bidentate ligand, where Y103 and Y104 are independently selected from C, N, O, P, and S; L101 is another ligand; k' is an integer value from 1 to the maximum number of ligands that can be bound to the metal; and k'+k'' is the maximum number of ligands that can be bound to the metal.

[0142] In one embodiment, the metal complex is: [ka] where (ON) is a bidentate ligand with the metal coordinated to atoms O and N.

[0143] In another embodiment, Met is selected from Ir and Pt. In a further embodiment, (Y103-Y104) is a carbene ligand.

[0144] In one embodiment, the host compound is selected from the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene; 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, indazoline, and aromatic heterocyclic compounds such as benzofuropyridine, 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 aromatic hydrocarbon cyclic groups and aromatic heterocyclic groups, which may be the same or different groups and which have 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 within each group can be unsubstituted or substituted with a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0145] In one embodiment, the host compound contains at least one of the following groups in the molecule: [ka] [ka] wherein R101 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and when it is aryl or heteroaryl, it has the same definition as Ar mentioned above. k is an integer from 0 to 20 or 1 to 20. X101 to X108 are independently selected from C (including CH) or N. Z101 and Z102 are independently selected from NR101, O, or S.

[0146] Non-limiting examples of host materials that can be used in OLEDs in combination with the materials disclosed herein are exemplified below along with references that disclose these materials. EP2034538, EP2034538A, EP2757608, JP2007254297, KR20100079458, KR20120088644, KR20120129733, KR20130115564 , TW201329200, US20030175553, US20050238919, US20060280965, US20090017330, US20090030202, US20090167162, US2 0090302743, US20090309488, US20100012931, US20100084966, US20100187984, US2010187984, US2012075273, US2012 126221, US2013009543, US2013105787, US2013175519, US2014001446, US20140183503, US20140225088, US2014034914, US7154114, WO2001039234, WO2004093207, WO2005014551, WO2005089025, WO2006072002, WO2006114966, WO200706375 4. WO2008056746, WO2009003898, WO2009021126, WO2009063833, WO2009066778, WO2009066779, WO2009086028, WO20100 56066, WO2010107244, WO2011081423, WO2011081431, WO2011086863, WO2012128298, WO2012133644, WO2012133649, WO 2013024872, WO2013035275, WO2013081315, WO2013191404, WO2014142472, US20170263869, US20160163995, US9466803

change

change

change

change

[0147] One or more additional emitter dopants can be used together with the compound of the present disclosure.The example of the additional emitter dopant is not particularly limited, and any compound can be used as long as the compound is typically used as an emitter material.Examples of suitable emitter materials include, but are not limited to, compounds that can generate light emission through phosphorescence, fluorescence, thermally activated delayed fluorescence (TADF, also known as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0148] Non-limiting examples of emitter materials that can be used in OLEDs in combination with the materials disclosed herein are exemplified below along with references 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, US 2014103305, US6303238, US6413656, US6653654, US6670645, US6687266, US6835469, US6921915, US7279704, US73 32232, US7378162, US7534505, US7675228, US7728137, US7740957, US7759489, US7951947, US8067099, US8592586 , US8871361, WO06081973, WO06121811, WO07018067, WO07108362, WO07115970, WO07115981, WO08035571, WO200201 5645, WO2003040257, WO2005019373, WO2006056418, WO2008054584, WO2008078800, WO2008096609, WO2008101842 , WO2009000673, WO2009050281, WO2009100991, WO2010028151, WO2010054731, WO2010086089, WO2010118029, WO20 11044988, WO2011051404, WO2011107491, WO2012020327, WO2012163471, WO2013094620, WO2013107487, WO201317 4471, WO2014007565, WO2014008982, WO2014023377, WO2014024131, WO2014031977, WO2014038456, WO2014112450,

change

change

change

change

[0149] A hole-blocking layer (HBL) can be used to reduce the number of holes and / or excitons that escape from the emissive layer. The presence of such a blocking layer in a device can result in significantly higher efficiency and / or longer lifetime compared to a similar device lacking a blocking layer. A blocking layer can also be used to confine emission to a desired region of an OLED. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and / or a higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and / or a higher triplet energy than one or more of the hosts closest to the HBL interface.

[0150] In one embodiment, the compounds used in the HBL contain the same molecules or the same functional groups as those used in the hosts described above.

[0151] In another embodiment, the compound used in the HBL comprises at least one of the following groups in the molecule: [ka] wherein k is an integer from 1 to 20; L101 is another ligand; and k' is an integer from 1 to 3. g)ETL:

[0152] The electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or doped. Doping may be used to enhance conductivity. Examples of ETL materials are not particularly limited, and any metal complex or organic compound typically used to transport electrons may be used.

[0153] In one embodiment, the compound used in the ETL contains at least one of the following groups in the molecule: [ka] wherein R101 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and when it is aryl or heteroaryl, it has the same definition as Ar mentioned above. Ar1 to Ar3 have the same definition as Ar mentioned above. k is an integer from 1 to 20. X101 to X108 are selected from C (including CH) or N.

[0154] In another embodiment, the metal complex used in the ETL comprises, but is not limited to, the following general formula: [ka] where (ON) or (NN) is a bidentate ligand with the metal coordinated to atoms O, N, or N,N; L101 is another ligand; and k' is an integer value from 1 to the maximum number of ligands that can be bound to the metal.

[0155] Non-limiting examples of ETL materials that can be used in OLEDs in combination with the materials disclosed herein are exemplified below along with references that disclose these materials. CN103508940, EP01602648, EP01734038, EP01956007, JP2004-022334, JP2 005149918, JP2005-268199, KR0117693, KR20130108183, US20040036077, U S20070104977, US2007018155, US20090101870, US20090115316, US20090140637, US20090179554, US2009218940, US2010108990, US2011156017, US20 11210320, US2012193612, US2012214993, US2014014925, US2014014927, US20140284580, US6656612, US8415031, WO2003060956, WO2007111263, WO20 09148269, WO2010067894, WO2010072300, WO2011074770, WO2011105373, W O2013079217, WO2013145667, WO2013180376, WO2014104499, WO2014104535 [ka] [ka] [ka] h) Charge Generation Layer (CGL)

[0156] In tandem or stacked OLEDs, the CGL plays a key 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. Consumed electrons and holes in the CGL are replenished by electrons and holes injected from the cathode and anode, respectively, until the bipolar current gradually reaches a steady state. Typical CGL materials contain n-type and p-type conductivity dopants used in the transport layers.

[0157] In any of the above-mentioned compounds used in each layer of an OLED device, the hydrogen atoms may be partially or fully deuterated. Thus, any specifically recited substituent, such as, but not limited to, methyl, phenyl, pyridyl, etc., can be undeuterated, partially deuterated, and fully deuterated versions thereof. Similarly, substituent classes, such as, but not limited to, alkyl, aryl, cycloalkyl, heteroaryl, etc., can be undeuterated, partially deuterated, and fully deuterated versions thereof. It is understood that the various embodiments described herein are by way of example only and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein can be substituted with other materials and structures without departing from the spirit of the invention. Thus, the present invention as claimed may 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 various theories as to why the invention works are not intended to be limiting. experiment

[0158] Scheme

[0159] Example of the present invention: Synthesis of Ir(LB26)2(LA3-1-1) [ka]

[0160] Process 1 [ka] Synthesis of 2-chloro-5-methyl-4-(2,4,5-trimethyl)pyridine: 2-chloro-4-iodo-5-methylpyridine (12 g, 47.3 mmol), (2,4,5-trimethylphenyl)boronic acid (8.54 g, 52.1 mmol), dicyclohexyl(2',4',6'-triisopropyl-[1,1'-biphenyl]-2-yl)phosphane (0.677 g, 1.420 mmol), potassium phosphate tribasic monohydrate (32.7 g, 142 mmol), and THF (90 mL) were added to a 250 mL round-bottom flask. Nitrogen was bubbled through the mixture, and diacetoxypalladium (0.106 g, 0.473 mmol) was added. The mixture was stirred overnight at room temperature under nitrogen. The mixture was partitioned between water and ethyl acetate. The layers were separated and the aqueous layer was extracted with ethyl acetate. The organic layer was washed with brine, dried over magnesium sulfate, filtered, and evaporated. It was taken up in DCM and purified by column chromatography eluting with 50-100% DCM / heptane to give 10.23 g (81% yield) of a solid.

[0161] Process 2 [ka] Synthesis of 5-methyl-2-(naphtho[1,2-b]benzofuran-10-yl)-4-(2,4,5-trimethylphenyl)pyridine: 10-chloronaphtho[1,2-b]benzofuran (3.0 g, 11.87 mmol), 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi(1,3,2-dioxaborolane) (6.03 g, 23.74 mmol), and potassium acetate (3.50 g, 35.6 mmol) were added to 1,4-dioxane (90 ml) in a 500 ml three-neck flask. The reaction mixture was purged with nitrogen for 15 minutes, after which Pd(dba) (0.217 g, 0.237 mmol) and dichlorohexyl(2',6'-dimethoxy-[1,1'-biphenyl]-2-yl)phosphane (0.390 g, 0.950 mmol) were added. The reaction mixture was heated overnight (~16 hours) in an oil bath set at 110 °C. The reaction mixture was cooled, and 2-chloro-5-methyl-4-(2,4,5-trimethylphenyl)pyridine (2.92 g, 11.87 mmol), 54 ml of dioxane, potassium phosphate (7.56 g, 35.6 mmol), and 48 ml of water were added. The reaction mixture was purged with nitrogen, and then Pd(PhP) (0.412 g, 0.356 mmol) was added. The reaction mixture was heated overnight in an oil bath set at 100 °C. After dilution with ethyl acetate and water, the layers were separated and the aqueous layer was extracted twice more with ethyl acetate, the organic layer was washed with brine, dried over magnesium sulfate, filtered and evaporated. The crude material was purified by column chromatography eluting with 10-40% ethyl acetate / heptane to give 3.27 g (64%) of a white solid.

[0162] Process 3 [ka] Synthesis of 5-(methyl-d3)-2-(naphtho[1,2-b]benzofuran-10-yl)-4-(2,4,5-tris(methyl-d3)phenyl)pyridine: 5-Methyl-2-(naphtho[1,2-b]benzofuran-10-yl)-4-(2,4,5-trimethylphenyl)pyridine (3.27 g, 7.65 mmol) and ((methyl-d3)sulfinyl)methane-d3 (25 mL, 356 mmol) were added to a 100 mL three-necked round-bottom flask. The flask was then evacuated and replaced with nitrogen three times. Sodium 2-methylpropan-2-olate (0.368 g, 3.82 mmol) was added, and the degassing and nitrogen replacement procedures were repeated. The reaction mixture was heated to 90 °C under nitrogen. The reaction mixture was then transferred to a 500 mL three-neck round-bottom flask and an additional 175 mL of DMSO-d6 was added. The degassing and nitrogen flushing procedure was repeated three times. The reaction mixture was heated to 90 °C under nitrogen. At this point, most of the material was in solution and the mixture turned from tan to brown. The flask and oil bath were covered with aluminum foil; cooled; DO was added and stirred; diluted with water; extracted twice with dichloromethane; washed the organics with 10% LiCl solution; washed with brine; dried over magnesium sulfate; filtered; and evaporated to give a yellow solid (wt. = 5.23 g). The crude material was purified using a silica gel plug eluting with dichloromethane.

[0163] Process 4 [ka] Synthesis of an inventive example: The triflate salt (1.9 g, 2.430 mmol), 5-(methyl-d3)-2-(naphtho[1,2-b]benzofuran-10-yl)-4-(2,4,5-tris(methyl-d3)phenyl)pyridine (1.923 g, 4.37 mmol), DMF (50 mL), and 2-ethoxyethanol (50.0 mL) were added to a 500 mL round-bottom flask. The flask was evacuated and flushed with nitrogen three times. The reaction mixture was heated to 100 °C (oil bath) overnight (~16 hours). The reaction mixture was heated at 100 °C for 2.5 weeks. The reaction mixture was diluted with methanol; filtered through a Celite pad; washed with methanol; and the material was recovered by washing the Celite with DCM; and the DCM was evaporated to give a solid. The crude material was purified by column chromatography eluting with 70% toluene / heptane followed by pure toluene to yield 1 g (41%) of product.

[0164] Synthesis of Comparative Example [ka] The comparative examples were synthesized using the same method as the inventive examples.

[0165] Device Example

[0166] All example devices were fabricated by thermal evaporation under high vacuum (<10-7 Torr). The anode electrode was 800 Å of indium tin oxide (ITO). The cathode consisted of 10 Å of Liq (8-hydroxyquinoline lithium) and 1,000 Å of Al. All devices were immediately encapsulated with a glass lid sealed with epoxy resin in a nitrogen glove box (<1 ppm H2O and O2) after fabrication, and a moisture getter was included in the package. The organic stack of the example devices consisted of, 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 400 Å-thick light-emitting layer (EML). The light-emitting layer contained a 6:4 ratio of H-host (H1):E-host (H2) and 12 wt% of a green emitter. The ETL was 350 Å of Liq (8-hydroxyquinoline lithium) doped with 40% ETM. The schematic structure of each device is shown in Table 1. The chemical structures of the device materials are shown below. [ka] [ka]

[0167] After fabrication, the electroluminescence (EL) and current density-voltage-luminance (JVL) characteristics of each device were measured, and a lifespan test was performed at 80 mA / cm2 DC, with the LT95 calculated at 1,000 nits. From the LT95 data, an acceleration factor of 1.8 was assumed. The device data were normalized to the comparative example and are shown in Table 2.

[0168] Table 1: Device structure overview [Table 1] Table 2: Device performance data [Table 2]

[0169] Comparison of device performance data for inventive and comparative examples: both the efficiency and lifetime of the inventive examples are significantly higher than those of the comparative examples. We speculate that the partially twisted aryl substitution favors better alignment of the transition dipole moment of the molecule than the pure methyl case. This concept is illustrated in Figure 3. [Explanation of symbols]

[0170] 100 Organic Light-Emitting Devices 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 Protective 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. An organic light emitting device (OLED) material comprising a first ligand LA of formula I: 【Chemical 1】 (Wherein, X1 to X4 are each independently C or N; X1a to X4a are each independently C or N; At least two of X1 to X4 are C; X1 to X4 bonded to ring A are C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; Ring C is a fused ring structure containing three or more fused heterocyclic or carbocyclic rings; RA, RB, and RC each represent zero, one, or up to the maximum number of substitutions allowed; each R, R, and R is independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; any two substituents may be bonded or fused together to form a ring; said ligand LA complexes with a metal M; M is selected from the group consisting of Os, Ir, Pd, Pt, Cu, Ag, and Au; The ligand LA can be combined with other ligands to form tridentate, tetradentate, pentadentate, or hexadentate ligands.

2. 2. The organic light-emitting device (OLED) material of claim 1, wherein X1 to X4 are each C.

3. 10. The organic light emitting device (OLED) material of claim 1, wherein R1 is an alkyl group which may be partially or fully deuterated.

4. 10. The organic light-emitting device (OLED) material of claim 1, wherein ring C comprises two six-membered rings and one five-membered ring; three six-membered rings and one five-membered ring; or three six-membered rings and two five-membered rings.

5. 10. The organic light-emitting device (OLED) material of claim 1, wherein X3 is bonded to ring A.

6. 6. The organic light emitting device (OLED) material of claim 5, wherein the ligand LA has the following formula II: 【Chemistry 2】 wherein X is selected from the group consisting of O, S, Se, NR, CRR′, and SiRR′; R and R′ are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, aryl, heteroaryl, and combinations thereof; X5 to X12 are each independently C or N; X5 to X12 which form a bond with M are C; The maximum number of N atoms that can be bonded to each other is 2; Two R C substituents can be bonded to or fused to each other to form a ring.

7. 7. The organic light-emitting device (OLED) material according to claim 6, wherein when two R Cs are bonded to or fused with each other to form a ring, any two selected from R C bonded to X9, R C bonded to X10, R C bonded to X11, and R C bonded to X12 are bonded to or fused with each other to form a ring.

8. 7. The organic light emitting device (OLED) material of claim 6, wherein X is O.

9. 7. The organic light emitting device (OLED) material of claim 6, wherein X5 to X12 are each C, or at least one of X5 to X12 is N.

10. 7. The organic light emitting device (OLED) material of claim 6, wherein two R.sup.C substituents are joined together to form a 5- or 6-membered aromatic ring which may be further fused or substituted.

11. 2. The organic light emitting device (OLED) material of claim 1, wherein the ligand LA is selected from the group consisting of: 【Chemistry 3】 【Chemistry 4】 【Chemistry 5】 【Chemistry 6】 wherein X and Y are each independently selected from the group consisting of O, S, NR, CRR′, and SiRR′; RD represents zero, mono, and up to the maximum number of substitutions allowed on the associated ring; Each RD is independently hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, and combinations thereof.

12. 2. The organic light emitting device (OLED) material of claim 1, wherein the ligands LA are defined by the formula LAi-N-M, where i is an integer from 1 to 14, N is an integer from 1 up to 7, and M is an integer from 1 to 649; each LAi-N is defined as follows: 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 【Chemistry 10】 where for each LAi-N, the substituents R1, RA, and RB are defined in the table below as a series of M. 【Chemistry 11】 【Chemistry 12】 【Chemistry 13】 【Chemistry 14】 【Chemistry 15】 【Chemistry 16】 【Chemistry 17】 【Chemistry 18】 【Chemistry 19】 (wherein the substituents A to Z″ are defined as follows.) 【Chemistry 20】 【Chemical 21】

13. 10. The organic light emitting device (OLED) material of claim 1, wherein the OLED material has the formula M(LA)x(LB)y(LC)z, where LB and LC are each bidentate ligands; x is 1, 2, or 3; y is 0, 1, or 2; z is 0, 1, or 2; and x + y + z is the oxidation state of the metal M.

14. The organic light emitting device (OLED) material may be a compound Ai-N-M having the formula Ir(LAi-N-M)3, a compound Bi-N-M-k having the formula Ir(LAi-N-M)(LBk), a compound Ci-N-M-k having the formula Ir(LAi-N-M)2(LBk), a compound Di-N-M-j-I having the formula Ir(LAi-N-M)(LCj-I), or a compound of the formula Ir(LAi-N-M 13. The organic light emitting device (OLED) material of claim 12, wherein LBl through LBl264 have the structures shown below: 【Chemical 22】 【Chemical 23】 【Chemistry 24】 【Chemistry 25】 【Chemical 26】 【Chemical 27】 【Chemical Formula 28】 【Chemical 29】 【Chemistry 30】 (Wherein LCj-I is the following: 【Chemical 31】 having a structure based on LCj-II is as follows: 【Chemical 32】 wherein in each LCj in LCj-I and LCj-II, R1' and R2' are defined as shown below. 【Chemical Formula 33】 【Chemical 34】 【Chemical 35】 【Chemical Formula 36】 【Chemical 37】 【Chemical Formula 38】 【Chemical Formula 39】 (Wherein, RD1 to RD192 have the following structures.) 【Chemistry 40】 【Chemistry 41】 【Chemistry 42】 【Chemistry 43】

15. An organic layer comprising a compound comprising a first ligand LA of formula I: 【Chemical 44】 (Wherein, X1 to X4 are each independently C or N; X1a to X4a are each independently C or N; At least two of X1 to X4 are C; X1 to X4 bonded to ring A are C; Z is C or N; R1 is selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, and combinations thereof; Ring C is a fused ring structure containing three or more fused heterocyclic or carbocyclic rings; RA, RB, and RC each represent zero, one, or up to the maximum number of substitutions allowed; each R, R, and R is independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; any two substituents may be bonded or fused together to form a ring; said ligand LA complexes with a metal M; M is selected from the group consisting of Os, Ir, Pd, Pt, Cu, Ag, and Au; The ligand LA can be combined with other ligands to form tridentate, tetradentate, pentadentate, or hexadentate ligands.

16. 2. The organic light emitting device (OLED) material of claim 1, wherein the OLED material is selected from the group consisting of: 【Chemistry 46】 【Chemistry 47】 【Chemistry 48】 【Chemistry 49】 【Chemistry 50】 【Chemistry 51】

Images