Organic electroluminescent materials and devices

Abstract

The present invention relates to organic electroluminescent materials and devices. Novel ligands for metal complexes containing a five-membered ring fused on a pyridine or pyrimidine ring, combined with partially fluorinated side chains, which exhibit improved external quantum efficiency and lifetime are disclosed.

Description

[0001] This application is a divisional application of the invention patent application with application date of May 13, 2016, application number 201610318751.7, and invention name “Organic electroluminescent materials and devices”.

[0002] Cross Reference to Related Applications

[0003] This application is a non-provisional U.S. patent application claiming priority under 35 U.S.C. §119(e)(1) to U.S. patent application No. 62 / 161,948, filed May 15, 2015, the entire contents of which are incorporated herein by reference.

[0004] Parties to Joint Research Agreement

[0005] The claimed invention was made by, on behalf of, and / or in conjunction with one or more of the following parties to a joint university-corporate research agreement: The Regents of the University of Michigan, Princeton University, the University of Southern California, and Universal Display Corporation. Said agreement was in effect on and before the date the claimed invention was made, and the claimed invention was made as a result of activities performed within the scope of said agreement. Technical Field

[0006] The present invention relates to compounds suitable for use as emitters; and devices including the same, such as organic light emitting diodes. Background Art

[0007] Optical electronic devices that utilize organic materials are becoming increasingly popular for several reasons. Many of the materials used to make such devices are relatively inexpensive, so organic optical electronic devices have the potential to gain cost advantages over inorganic devices. In addition, the inherent properties of organic materials (such as their flexibility) can make them well suited for specific applications, such as fabrication on flexible substrates. Examples of organic optical electronic devices include organic light emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can have performance advantages over conventional materials. For example, the wavelength of light emitted by the organic emissive layer can generally be easily adjusted with appropriate dopants.

[0008] OLEDs make use of thin organic films that emit light when voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in the display panel industry due to their low power consumption, high contrast, and good viewing angles. Several OLED materials and configurations are described in U.S. Patent Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.

[0009] One application for phosphorescent emission is a full color display. Industry standards for such displays require that pixels be adapted to emit particular colors, referred to as "saturated" colors. Specifically, these standards require saturated red, green, and blue pixels. Alternatively, an OLED can be designed to emit white light. In conventional liquid crystal displays, absorbing color filters are used to filter emissions from a white backlight to produce red, green, and blue emissions. The same technology can be used for OLEDs. A white OLED can be a single EML device or a stacked structure. Color can be measured using CIE coordinates, which are well known in the art.

[0010] One example of a green emissive molecule is tris(2-phenylpyridine) iridium, denoted as Ir(ppy)3, which has the following structure:

[0011]

[0012] In this structure and the structures below, the bond from nitrogen to metal (here, Ir) is depicted as a straight line.

[0013] As used herein, the term "organic" includes polymeric materials, as well as small molecule organic materials that can be used to fabricate organic opto-electronic devices. "Small molecules" refer to any organic materials that are not polymers, and "small molecules" can actually be quite large. In some cases, small molecules can include repeating units. For example, a molecule that contains a long chain alkyl segment is not necessarily removed from the "small molecule" class. Small molecules can also be incorporated into polymers, for example as a pendent group on a polymer backbone or as a portion of the backbone. Small molecules can also serve as the core moiety of a dendrimer, which consists of a series of chemical shells built on a core moiety. A core moiety can be a fluorescent or phosphorescent small molecule emitter. Dendrimer can be "small molecules," and all dendrimers currently in active use in the OLED

[0014] As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. Where a first layer is described as "disposed" on a second layer, the first layer is disposed farther from the substrate. Unless specified otherwise, there can be intervening layers between the first and second layers. For example, a cathode can be described as "disposed on" an anode even though various organic layers are between the cathode and the anode.

[0015] As used herein, "solution processible" means capable of being dissolved, dispersed, or transported in and / or deposited from a liquid medium, either in solution or suspension form.

[0016] A ligand can be referred to as "photosensitive" when it is believed to directly contribute to the photoactive properties of the emissive material. A ligand can be referred to as "auxiliary" when it is believed not to contribute to the photoactive properties of the emissive material, although an auxiliary ligand can alter the properties of a photosensitive ligand.

[0017] As used herein, and as generally understood by one of skill 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. Since ionization potential (IP) is measured as a negative energy with respect to the vacuum energy 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 energy level at the top, a material's LUMO energy level is higher than its HOMO energy level. A "higher" HOMO or LUMO energy level appears closer to the top of this diagram than a "lower" HOMO or LUMO energy level.

[0018] As used herein, and as generally understood by one of skill 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. Since work functions are typically measured as negative numbers relative to the vacuum energy level, this means a "higher" work function is more negative. On a conventional energy level diagram, with the vacuum energy level at the top, a "higher" work function is said to be "farther" from the vacuum energy level in the downward direction. Thus, the definitions of HOMO and LUMO energy levels follow a different convention than work functions.

[0019] More details on OLEDs and the definitions described above can be found in U.S. Patent No. 7,279,704, which is incorporated herein by reference in its entirety. SUMMARY

[0020] According to some embodiments of the application, a compound is disclosed comprising a ligand L of formula IA ,

[0021] wherein ring A is a 5- or 6-membered carbocyclic or heterocyclic ring;

[0022] wherein R is fused to ring B and has the structure of Formula II:

[0023]

[0024] wherein the wavy line indicates a bond to ring B;

[0025] wherein R 1 represents a mono-, di-, tri-, or tetra-substituted or no substitution;

[0026] wherein R 2 represents a mono- or di-substituted or no substitution;

[0027] wherein X 1 , X 2 , X 3 , and X 4 are each independently carbon or nitrogen;

[0028] wherein at least two adjacent X 1 , X 2 , X 3 , and X 4 are carbon and fused to R;

[0029] wherein X is selected from the group consisting of BR', NR', PR', O, S, Se, C=O, S=O, SO2, CR'R", SiR'R", and GeR'R";

[0030] wherein R 1 , R 2 , R 3 , R 4 , R', and R" are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxyl, ester, nitrite, isonitrile, thio, sulfoxyl, sulfonyl, phosphino, and combinations thereof; and wherein any two adjacent substituents are optionally connected to form a ring;

[0031] wherein at least one of R 3 and R 4 comprises a chemical group selected from the group consisting of alkyl, cycloalkyl, partially fluorinated alkyl, partially fluorinated cycloalkyl, and combinations thereof;

[0032] wherein the ligand L A is coordinated to the metal M;

[0033] wherein the ligand L A optionally linked with other ligands to comprise a tridentate, tetradentate, pentadentate, or hexadentate ligand; and

[0034] wherein M is optionally coordinated to other ligands.

[0035] According to some embodiments, a first OLED is disclosed, comprising an anode, a cathode, and an organic layer disposed between the anode and the cathode, the organic layer including a compound comprising a ligand L A of Formula I.

[0036] According to some embodiments, a formulation is also disclosed, including a compound comprising a ligand L A of Formula I. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 An organic light emitting device is shown.

[0038] Figure 2 An inverted organic light emitting device is shown without a separate electron transport layer. DETAILED DESCRIPTION

[0039] Generally, an OLED includes at least one organic layer disposed between and electrically connected to an anode and a cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons each migrate toward the oppositely charged electrode. When an electron and hole localize on the same molecule, an "exciton," which is a localized electron-hole pair having an excited energy state, is formed. When the exciton relaxes via a photoemissive mechanism, light is emitted. In some cases, the exciton can localize on an excimer or exciplex. Non- radiative mechanisms, such as thermal relaxation, can also occur, but are generally considered undesirable.

[0040] Initial OLEDs used emitters that emitted light from a singlet state ("fluorescence"), as disclosed, for example, in U.S. Patent No. 4,769,292, which is incorporated by reference in its entirety. Fluorescent emission generally occurs in the time frame of less than 10 nanoseconds.

[0041] Recently, OLEDs with emissive materials that emit light from triplet states ("phosphorescence") have been demonstrated. Baldo et al., "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices," Nature, Vol. 395, pp. 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, pp. 4-6 (1999) ("Baldo-II") are incorporated by reference in their entirety. Phosphorescence is described in more detail in U.S. Patent No. 7,279,704, columns 5-6, incorporated by reference.

[0042] Figure 1 An organic light-emitting device 100 is shown. The figures are not necessarily drawn 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 composite cathode having a first conductive layer 162 and a second conductive layer 164. Device 100 can be fabricated by sequentially depositing the described layers. The properties and functions of these various layers and example materials are described in more detail in columns 6-10 of US Pat. No. 7,279,704, which is incorporated by reference.

[0043] There are more examples of each of these layers. For example, flexible and transparent substrate-anode combinations are disclosed in U.S. Patent No. 5,844,363, incorporated by reference in its entirety. An example of a p-doped hole-transporting layer is m-MTDATA doped with F4-TCNQ in a 50:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, incorporated by reference in its entirety. Examples of emissive materials and host materials are disclosed in U.S. Patent No. 6,303,238, issued to Thompson et al., incorporated by reference in its entirety. An example of an n-doped electron-transporting layer is BPhen doped with Li in a 1:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, incorporated by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, incorporated by reference in their entireties, disclose examples of cathodes, including composite cathodes with a thin layer of metal, such as Mg:Ag, overlying a transparent, conductive, sputter-deposited ITO layer. The principles and use of a blocking layer are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, incorporated by reference in their entireties. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004 / 0174116, incorporated by reference in its entirety. A description of a protective layer can be found in U.S. Patent Application Publication No. 2004 / 0174116, incorporated by reference in its entirety.

[0044] Figure 2 An inverted OLED 200 is shown. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole-transporting layer 225, and an anode 230. Device 200 can be fabricated by sequentially depositing the layers described. Because the most common OLED configuration has a cathode disposed over an anode, and device 200 has a cathode 215 disposed under anode 230, device 200 can be referred to as an "inverted" OLED. In the corresponding layers of device 200, similar materials to those described with respect to device 100 can be used. Figure 2 One example of how some layers can be omitted from the structure of device 100 is provided.

[0045] Figure 1 and 2The simple layered structure illustrated in the middle is provided as an non-limiting example, and it is understood that embodiments of the application can be used in combination with a variety of other structures. The specific materials and structures described are exemplary in nature and other materials and structures can be used. Functional OLEDs can be achieved by combining the various layers described in different ways, as appropriate to a particular design, performance, and cost constraints. Also, other layers not specifically described can be included in the OLED structure. Materials other than those specifically described can be employed. Although many of the examples provided herein describe various layers as having a single material, it is understood that combinations of materials can be used, e.g., a mixture of host and dopant, or more generally a mixture of materials. Also, the layers can have various sub-layers. The names given to the various layers in this disclosure are not intended to be strictly limiting. For example, in device 200, the hole transport layer 225 transports holes and injects holes into the emission layer 220, and can be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED can be described as having an "organic layer" disposed between a cathode and an anode. This organic layer can include a single layer, or can further include multiple layers of different organic materials as described, for example, with respect to FIGS. 1 A-1C of U.S. Patent No. 5,247,190, which is incorporated by reference in its entirety. Figure 1 and 2 The simple layered structure illustrated in the middle is provided as an non-limiting example, and it is understood that embodiments of the application can be used in combination with a variety of other structures. The specific materials and structures described are exemplary in nature and other materials and structures can be used. Functional OLEDs can be achieved by combining the various layers described in different ways, as appropriate to a particular design, performance, and cost constraints. Also, other layers not specifically described can be included in the OLED structure. Materials other than those specifically described can be employed. Although many of the examples provided herein describe various layers as having a single material, it is understood that combinations of materials can be used, e.g., a mixture of host and dopant, or more generally a mixture of materials. Also, the layers can have various sub-layers. The names given to the various layers in this disclosure are not intended to be strictly limiting. For example, in device 200, the hole transport layer 225 transports holes and injects holes into the emission layer 220, and can be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED can be described as having an "organic layer" disposed between a cathode and an anode. This organic layer can include a single layer, or can further include multiple layers of different organic materials as described, for example, with respect to FIGS. 1 A-1C of U.S. Patent No. 5,247,190, which is incorporated by reference in its entirety.

[0046] Other structures and materials can be used without departing from the scope of the application, e.g., OLEDs including polymeric materials such as described in U.S. Patent No. 5,247,190, which is incorporated by reference in its entirety, for example. As another example, OLEDs can be used that include a single organic layer. OLEDs can be stacked, as described in U.S. Patent No. 5,707,745, which is incorporated by reference in its entirety, for example. OLED structures can depart from the simple layered structure illustrated in FIGS. 1 A-1C, and FIG. 2, without departing from the scope of the application. For example, a substrate can include an angled reflective surface to improve out-coupling, such as a table structure as described in U.S. Patent No. 6,091,195, and / or a dimple structure as described in U.S. Patent No. 5,834,893, which are incorporated by reference in their entireties. Figure 1 2 Other structures and materials can be used without departing from the scope of the application, e.g., OLEDs including polymeric materials such as described in U.S. Patent No. 5,247,190, which is incorporated by reference in its entirety, for example. As another example, OLEDs can be used that include a single organic layer. OLEDs can be stacked, as described in U.S. Patent No. 5,707,745, which is incorporated by reference in its entirety, for example. OLED structures can depart from the simple layered structure illustrated in FIGS. 1 A-1C, and FIG. 2, without departing from the scope of the application. For example, a substrate can include an angled reflective surface to improve out-coupling, such as a table structure as described in U.S. Patent No. 6,091,195, and / or a dimple structure as described in U.S. Patent No. 5,834,893, which are incorporated by reference in their entireties.

[0047] ​Unless otherwise described, any of the layers of the various embodiments can be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, ink-jet (for example as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, both of which are incorporated by reference in their entireties), organic vapor phase deposition (OVPD) (for example as described in U.S. Pat. No. 6,337,102, which is incorporated by reference in its entirety) and deposition by organic vapor jet printing (OVJP) (for example as 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 conducted in nitrogen or inert atmospheres. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding (for example as described in U.S. Pat. Nos. 6,294,398 and 6,468,819, both of which are incorporated by reference in their entireties) and patterning associated with some of the deposition methods such as ink-jet and OVJD. Other methods can also be used. The materials to be deposited can be modified in order to impart the properties of a particular deposition process. For example, for materials to be solution processed, alkyl or aryl substituents, for example, can be used to enhance solubility. Solubility in many organic solvents can be enhanced by using several alkyl or aryl substituents, for example. 20 or more carbons can be used, and 3-20 carbons are a preferred range. Materials with asymmetric structures can have better solution processibility than those with symmetric structures, because asymmetric materials can have a lower tendency to recrystallize. Dendrimer substituents can be used to enhance solution processibility of small molecules.

[0048] Devices fabricated in accordance with embodiments of the application can further optionally include a barrier layer. One use of a barrier layer is to protect the electrode and organic layer from the deleterious effects of exposure to the environment. The barrier layer can be deposited on the substrate, electrode, or both, and can be deposited on the entire surface or only on portions of the surface. Multiple layers can be deposited, for example, to improve durability of the device. The barrier layer can be formed by various known chemical vapor deposition techniques and can include compositions that are in a single phase as well as compositions that are in multiple phases. Any suitable material or combination of materials can be used for the barrier layer. The barrier layer can be incorporated with an inorganic compound or an organic compound or both. Preferred barrier layers comprise a mixture of polymeric and non-polymeric materials, as described in U.S. Patent No. 7,968,146, PCT Patent Application Nos. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are incorporated herein by reference in their entirety. To be considered a "mixture," the aforementioned polymeric and non-polymeric materials making up the barrier layer should be deposited under the same reaction conditions and / or at the same time. The weight ratio of polymeric material to non-polymeric material can range from 95:5 to 5:95. The polymeric and non-polymeric materials can be produced from the same precursor material. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric silicon and inorganic silicon.

[0049] Devices manufactured according to embodiments of the present invention may be incorporated into a wide variety of electronic component modules (or units) that may be incorporated into a variety of electronic products or intermediate components. Examples of such electronic products or intermediate components include display screens, lighting devices (such as discrete light source devices or lighting panels), etc. that may be utilized by end-user product manufacturers. Such electronic component modules may optionally include drive electronics and / or power supplies. Devices manufactured according to embodiments of the present invention may be incorporated into a wide variety of consumer products having one or more electronic component modules (or units) incorporated therein. Such consumer products will include any kind of product containing one or more light sources and / or some type of visual display. Some examples of such consumer products include flat panel displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior lighting and / or signaling, heads-up displays, fully transparent or partially transparent displays, flexible displays, laser printers, phones, cell phones, tablet computers, tablet phones, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays, 3-D displays, vehicles, large area walls, theater or stadium screens, or signage. Various control mechanisms can be used to control the devices manufactured according to the present invention, including passive matrices and active matrices. Many of the devices are intended to be used in a temperature range that is comfortable for humans, such as 18 degrees Celsius to 30 degrees Celsius, and more preferably at room temperature (20-25 degrees Celsius), but can be used outside this temperature range (e.g., -40 degrees Celsius to +80 degrees Celsius).

[0050] The materials and structures described herein can be used in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors can use the materials and structures. More generally, organic devices such as organic transistors can use the materials and structures.

[0051] As used herein, the term "halo," "halogen," or "halide" includes fluorine, chlorine, bromine, and iodine.

[0052] As used herein, the term "alkyl" encompasses both straight-chain and branched-chain alkyl groups. Preferred alkyl groups are those containing from one to fifteen 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, 2,2-dimethylpropyl, and the like. In addition, the alkyl group may be optionally substituted.

[0053] As used herein, the term "cycloalkyl" encompasses cyclic alkyl groups. Preferred cycloalkyl groups are cycloalkyl groups containing three to ten ring carbon atoms, and include cyclopropyl, cyclopentyl, cyclohexyl, adamantyl, and the like. Additionally, the cycloalkyl group can be optionally substituted.

[0054] As used herein, the term "alkenyl" encompasses straight-chain and branched-chain alkenyl groups. Preferred alkenyl groups are alkenyl groups containing two to fifteen carbon atoms. Additionally, the alkenyl group can be optionally substituted.

[0055] As used herein, the term "alkynyl" encompasses straight-chain and branched-chain alkynyl groups. Preferred alkynyl groups are alkynyl groups containing two to fifteen carbon atoms. Additionally, the alkynyl group can be optionally substituted.

[0056] As used herein, the terms "aralkyl" or "arylalkyl" are used interchangeably and encompass alkyl groups having an aromatic group as a substituent. Additionally, the aralkyl group can be optionally substituted.

[0057] As used herein, the term "heterocyclyl" encompasses both aromatic and non-aromatic cyclic groups. Heteroaromatic cyclic groups also mean heteroaryl groups. Preferred heteronon-aromatic cyclic groups are heterocyclic groups containing three to seven ring atoms including at least one heteroatom, and include cyclic amines, such as morpholinyl, piperidinyl, pyrrolidinyl, and the like, and cyclic ethers, such as tetrahydrofuran, tetrahydropyran, and the like. Additionally, the heterocyclyl group can be optionally substituted.

[0058] As used herein, the terms "aryl" or "aromatic group" encompass both monocyclic groups and polycyclic systems. Polycyclics can have two or more rings in which two carbons are shared by two adjacent rings (the rings are "fused"), where at least one of the rings is aromatic, for example the other rings can be cycloalkyl, cycloalkenyl, aryl, heterocyclyl, and / or heteroaryl. Preferred aryl groups are aryl groups containing six to thirty carbon atoms, preferably six to twenty carbon atoms, more preferably six to twelve carbon atoms. Especially preferred are aryl groups having six carbons, ten carbons, or twelve carbons. Suitable aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, pyrene, phenanthrene, fluorene, pyridine, chrysene, perylene, and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene, and naphthalene. Additionally, the aryl group can be optionally substituted.

[0059] As used herein, the term "heteroaryl" encompasses monocyclic heteroaromatic groups that can include one to five heteroatoms. The term heteroaryl also includes polycyclic heteroaromatic systems having two or more rings in which two atoms of the rings are shared by two adjacent rings (the rings are "fused"), where at least one of the rings is heteroaryl, for example the other rings can be cycloalkyl, cycloalkenyl, aryl, heterocyclo, and / or heteroaryl. Preferred heteroaryls are heteroaryls containing three to thirty carbon atoms, preferably three to twenty carbon atoms, more preferably three to twelve carbon atoms. Suitable heteroaryls include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolo-dipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazol, indolizine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthridine, phtalazine, pteridine, dibenzophuran, acridine, phenoxazine, phenothiazine, phenoxazine, benzofurodipyridine, furandipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenedipyridine, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, and nitrogen analogs thereof. Additionally, the heteroaryl can be optionally substituted.

[0060] Alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclyl, aryl, and heteroaryl can be unsubstituted or can be substituted by one or more substituents selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, cycloamino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxyl, ether, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, phosphine, and combinations thereof.

[0061] As used herein, "substituted" means that a substituent other than H is bonded to the relevant position, e.g., carbon. Thus, for example, in R 1 is not H. Similarly, in R 1 must not be H. Similarly, in R 1 is not H. Similarly, in R 1 must not be H. Similarly, in R 1 is not H. Similarly, in R 1 is hydrogen for all available positions.

[0062] The "aza" designation in the fragments described herein (i.e., aza-dibenzofurans, aza-dibenzothiophenes, etc.) means that one or more C-H groups in the respective fragment can be replaced with a nitrogen atom, for example and without any limitation, aza-triphenylenes encompass dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. Other nitrogen analogs of the aza-derivatives described above can be readily envisioned by one of ordinary skill in the art, and all such analogs are intended to be encompassed by the term as set forth herein.

[0063] It should be understood that when a molecular fragment is described as a substituent or otherwise attached to another moiety, its name can be written as if it were a fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or as if it were an entire molecule (e.g., benzene, naphthalene, dibenzofuran). These different ways of naming the substituent or attached fragment are considered equivalent as used herein.

[0064] According to one aspect of the present invention, ligands containing a five-membered ring fused on a pyridine or pyrimidine ring, combined with a partially fluorinated side chain, are disclosed, which are found to be suitable for phosphorescent light emitting metal complexes for use in organic light emitting devices. The resulting light emitting metal complexes exhibit improved external quantum efficiency and lifetime.

[0065] Some exemplary ligands disclosed herein are fluoropyrimidines, thienopyrimidines, pyrrolopyrimidines, and cyclopentapyrimidines. In some embodiments, these ligands can be combined with aliphatic substituents containing at least one F atom. The combination of these two moieties on a single ligand is used for a variety of reasons. Pyridine or pyrimidine based ligands for red dopants have shown excellent device efficiency and good lifetime. Incorporating one or more side chains containing F atoms will allow fine tuning of the color and in particular provide a red shift.

[0066] According to some embodiments, a compound is disclosed comprising a ligand L of Formula I A , wherein ring A is a 5- or 6-membered carbocyclic or heterocyclic ring;

[0067] wherein R is fused to ring B and has the structure of Formula II, wherein the wavy line indicates a bond to ring B;

[0068] wherein R 1 represents a mono-, di-, tri-, or tetra-substituted or no substitution;

[0069] wherein R 2 represents a mono- or di-substituted or no substitution;

[0070] wherein X 1 , X 2 , X 3 , and X4 each independently carbon or nitrogen;

[0071] wherein at least two adjacent X 1 , X 2 , X 3 and X 4 are carbon and fused to R;

[0072] wherein X is selected from the group consisting of BR', NR', PR', O, S, Se, C=O, S=O, SO2, CR'R", SiR'R", and GeR'R";

[0073] wherein R 1 , R 2 , R 3 , R 4 , R' and R" are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxyl, ester, nitrite, isonitrile, thio, sulfoxide, sulfone, phosphino, and combinations thereof; and wherein any two adjacent substituents are optionally linked to form a ring;

[0074] wherein at least one of R 3 and R 4 comprises a chemical group selected from the group consisting of alkyl, cycloalkyl, partially fluorinated alkyl, partially fluorinated cycloalkyl, and combinations thereof;

[0075] wherein the ligand L A is coordinated to the metal M;

[0076] wherein the ligand L A is optionally linked to other ligands to comprise a tridentate, tetradentate, pentadentate, or hexadentate ligand; and wherein M is optionally coordinated to other ligands.

[0077] In some embodiments of the compound, M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu.

[0078] In some embodiments of the compound, M is Ir or Pt.

[0079] In some embodiments of the compound, the ligand L A is selected from the group consisting of:

[0080]

[0081] In some embodiments of the compound, the ligand L A is:

[0082]

[0083] In some embodiments of the compound, the ligand L A is:

[0084]

[0085] In some embodiments of the compound, at least one of R 3 and R 4 is a chemical group selected from the group consisting of alkyl, cycloalkyl, partially fluorinated alkyl, partially fluorinated cycloalkyl, and combinations thereof.

[0086] In some embodiments of the compound, at least one of R 3 and R 4 is a chemical group selected from the group consisting of partially fluorinated alkyl, partially fluorinated cycloalkyl, and combinations thereof.

[0087] In some embodiments of the compound, R 3 and R 4 are not hydrogen.

[0088] In some embodiments of the compound, at least one of X 1 , X 2 , X 3 , and X 4 is nitrogen.

[0089] In some embodiments of the compound, X is O.

[0090] In some embodiments of the compound, X is NR’.

[0091] In some embodiments of the compound, X is CR’R” or SiR’R”.

[0092] In some embodiments of the compound, R 1 , R 2 , R 3 , R 4 , R’, and R” are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof.

[0093] In some embodiments of the compound, R 1 , R 2 , R 3 , R 4each of R' and R" is independently selected from the group consisting of hydrogen, deuterium, methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclopentyl, cyclohexyl, and combinations thereof.

[0094] In some embodiments of the compound, at least one of R 3 and R 4 is selected from the group consisting of:

[0095]

[0096]

[0097] In some embodiments of the compound, R 3 and R 4 are joined to form a ring structure selected from the group consisting of:

[0098]

[0099] In some embodiments of the compound, at least one of R 3 and R 4 is selected from the group consisting of:

[0100]

[0101] In some embodiments of the compound, the ligand L A is selected from the group consisting of:

[0102] wherein R 1 , R 3 , R 4 , and R' are as defined above.

[0103] In some embodiments of the compound, the ligand L A is selected from the group consisting of L A1 to L A750 as defined below:

[0104] L A1 to L A375 is based on the structure of Formula IV, wherein R 3 , R 4 , and X are defined as shown in Table 1 below:

[0105] Table 1

[0106]

[0107]

[0108]

[0109]

[0110] and L A376 to L A750 based on the structure of Formula V, wherein R 3 , R 4 and X are defined as shown in Table 2 below:

[0111] Table 2

[0112]

[0113]

[0114]

[0115] wherein R B1 to R B4 have the following structure:

[0116] In some embodiments of the compounds, the compounds have the structure of Formula III, (L A ) n Ir(L B ) 3-n wherein L B is a bidentate ligand and n is 1, 2, or 3.

[0117] In some embodiments of the compounds having the structure of Formula III, the ligand L B is selected from the group consisting of:

[0118]

[0119] In some embodiments of the compounds having the structure of Formula III, the compounds are selected from the group consisting of: Compound 1 through Compound 12,750;

[0120] wherein each compound x has the structure of Ir(L Ak )2(L Bj );

[0121] wherein x = 750j+k-750, k is an integer from 1 to 750, and j is an integer from 1 to 17; and wherein the ligands L B1 to L B17 are defined as follows:

[0122]

[0123] In some embodiments of the compound, the compound has the structure of Formula VI, (L A ) m Pt(L C ) 2-m where L C is a bidentate ligand and m is 1 or 2.

[0124] In some embodiments of the compound having the structure of Formula VI, m is 1 and L A is connected to L C to form a tetradentate ligand.

[0125] According to another aspect of the present application, a first organic light emitting device is disclosed, comprising: an anode; a cathode; and an organic layer disposed between the anode and the cathode. The organic layer includes a compound comprising a ligand L A of Formula I, where ring A is a 5- or 6-membered carbocyclic or heterocyclic ring;

[0126] where R is fused to ring B and has the structure of Formula II, where the wavy line indicates a bond to ring B;

[0127] where R 1 represents a mono-, di-, tri-, or tetra-substituted or no substitution;

[0128] where R 2 represents a mono- or di-substituted or no substitution;

[0129] where X 1 , X 2 , X 3 , and X 4 are each independently carbon or nitrogen;

[0130] where at least two adjacent X 1 , X 2 , X 3 , and X 4 are carbon and fused to R;

[0131] where X is selected from the group consisting of BR', NR', PR', O, S, Se, C=O, S=O, SO2, CR'R", SiR'R", and GeR'R";

[0132] where R 1 , R 2 , R 3 , R 4, R' and R" are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxyl, aryloxyl, aminyl, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxyl, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and wherein any two adjacent substituents are optionally linked to form a ring;

[0133] wherein R 3 and at least one of R 4 comprises a chemical group selected from the group consisting of alkyl, cycloalkyl, partially fluorinated alkyl, partially fluorinated cycloalkyl, and combinations thereof;

[0134] wherein L A coordinates to the metal M;

[0135] wherein L A is optionally bonded to other ligands to comprise a tridentate, tetradentate, pentadentate, or hexadentate ligand; and

[0136] wherein M is optionally coordinated to other ligands.

[0137] The organic light emitting devices disclosed herein can be incorporated into one or more of the following: consumer products, electronic component modules, organic light emitting devices, and lighting panels. The organic layer can be an emissive layer and the compound can be an emissive dopant in some embodiments, while the compound can be a non-emissive dopant in other embodiments.

[0138] The organic layer can also include a host. In some embodiments, two or more hosts are preferred. In some embodiments, the host used can be a) ambipolar, b) electron transporting, c) hole transporting, or d) a wide band gap material that plays a minimal role in charge transport. In some embodiments, the host can include a metal complex. The host can be a triphenylene containing benzo-fused thiophene or benzo-fused furan. Any substituents in the host can be non-fused substituents independently selected from the group consisting of C n H 2n+1 , OC n H 2n+1 , OAr1, N(C n H 2n+1 )2, N(Ar1)(Ar2), CH=CH-C n H 2n+1 , C≡C-C n H 2n+1 , Ar1, Ar1-Ar2, and C n H 2n-Ar1, or the host does not have a substituent. In the foregoing substituents, n can vary from 1 to 10; and Ar1and Ar2may be independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof. The host can be an inorganic compound. For example, a Zn-containing inorganic material, such as ZnS.

[0139] The host can be a compound comprising at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, azo-dibenzothiophene, azo-dibenzofuran, and azo-dibenzoselenophene. The host can include a metal complex.

[0140] The host can be, but is not limited to, a specific compound selected from the group consisting of:

[0141] and combinations thereof. Additional information regarding possible hosts is provided below.

[0142] According to another aspect of the present application, a formulation is disclosed comprising a compound comprising a ligand L of Formula I A as defined above. The formulation can include one or more components disclosed herein selected from the group consisting of a solvent, a host, a hole injection material, a hole transport material, and an electron transport layer material.

[0143] Combinations with other materials

[0144] The materials described herein as being useful for particular layers in an organic light emitting device can be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in conjunction with a variety of hosts, transport layers, blocking layers, injection layers, electrodes, and other layers that can be present. The materials described or referred to below are non-limiting examples of materials that can be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that can be useful in combination.

[0145] Conducting dopants:

[0146] The charge transport layer can be doped with a conductive dopant to substantially change its charge carrier density, which in turn will change its conductivity. The conductivity is increased by the creation of charge carriers in the matrix material, and depending on the type of dopant, a change in the Fermi level of a semiconductor can also be achieved. Hole transport layers can be doped with a p-type conductive dopant, and n-type conductive dopants are used in electron transport layers. Non-limiting examples of conductive dopants that can be combined with the materials disclosed herein for use in OLEDs are exemplified below along with references disclosing those materials:

[0147] EP 01617493, EP 01968131, EP 2020694, EP 2684932, US 20050139810, US 20070160905, US 20090167167, US 2010288362, WO 06081780, WO 2009003455, WO 2009008277, WO 2009011327, WO 2014009310, US 2007252140, US 2015060804, and US 2012146012.

[0148]

[0149] HIL / HTL:

[0150] The hole injection / transport material used in the present application is not particularly limited, and any compound can be used as long as the compound is typically used as a hole injection / transport material. Examples of the material include, but are not limited to, phthalocyanine or porphyrin derivatives; aromatic amine derivatives; indolocarbazole derivatives; fluorocarbon-containing polymers; polymers with conductive dopants; conductive polymers such as PEDOT / PSS; self-assembled monomers derived from compounds such as phosphonic acid and silane derivatives; metal oxide derivatives such as MoO x ; p-type semiconductor organic compounds such as 1,4,5,8,9,12-hexaazatriphenylhexacarbonitrile; metal complexes, and cross-linkable compounds.

[0151] Examples of the aromatic amine derivative used in the HIL or HTL include, but are not limited to, the following general structures:

[0152]

[0153] Ar 1 to Ar 9each Ar is selected from the group consisting of aromatic hydrocarbon ring compounds such as benzene, biphenyl, terphenyl, triphenylene, naphthalene, anthracene, pyrene, phenanthrene, fluorene, chrysene, xanthene, perylene, and azulene; aromatic heterocyclic ring compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoseleophene, carbazole, indolocarbazole, pyridylindole, pyrrolo-dipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoloxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthridine, phthalazine, pteridine, diphenophane, acridine, phenoxazine, phenothiazine, phenoxazine, benzofurodipyridine, furandipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenedipyridine; and the group consisting of 2 to 10 cyclic structural units that are groups of the same type or different types selected from aromatic hydrocarbon ring groups and aromatic heterocyclic ring groups, and are bonded to each other directly or via at least one of oxygen atoms, nitrogen atoms, sulfur atoms, silicon atoms, phosphorus atoms, boron atoms, chain structural units, and aliphatic ring groups. Each Ar can be unsubstituted or can be substituted with a substituent selected from the group consisting of deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxyl, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0154] In one aspect, Ar 1 to Ar 9 is independently selected from the group consisting of:

[0155]

[0156] wherein k is an integer from 1 to 20; X 101 to X 108 is C (including CH) or N; Z 101 is N Ar 1 , O, or S; Ar 1 has the same groups defined above.

[0157] Examples of metal complexes used in the HIL or HTL include, but are not limited to, the following general formula:

[0158]

[0159] wherein Met is a metal which can have an atomic weight greater than 40; (Y 101 -Y 102) is a bidentate ligand, Y 101 and Y 102 are independently selected from C, N, O, P, and S; L 101 is an ancillary ligand; k' is an integer value from 1 to the maximum number of ligands that can be attached to the metal; and k' + k" is the maximum number of ligands that can be attached to the metal.

[0160] In one aspect, (Y 101 -Y 102 ) is a 2-phenylpyridine derivative. In another aspect, (Y 101 -Y 102 ) is a carbene ligand. In another aspect, Met is selected from Ir, Pt, Os, and Zn. In another aspect, the metal complex has a solution-state minimum oxidation potential relative to the Fc + / Fc couple of less than about 0.6 V.

[0161] Non-limiting examples of HIL and HTL materials that can be combined with the materials disclosed herein for OLEDs are illustrated below along with references disclosing those materials:

[0162] 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.

[0163]

[0164]

[0165]

[0166]

[0167]

[0168]

[0169] EBL:

[0170] 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 substantially higher efficiencies and / or longer lifetimes than similar devices lacking the blocking layer. Additionally, the blocking layer can be used to confine the emission to a desired region of the OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or 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 as used in one of the hosts described below.

[0171] Host:

[0172] The light-emitting layer of the organic EL device of the present application preferably contains at least a metal complex as a light-emitting material, and can contain a host material using a metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound can be used as long as the triplet energy of the host is greater than that of the dopant. Although the following table classifies host materials that are preferably used in devices emitting various colors, any host material can be used with any dopant as long as the triplet criterion is satisfied.

[0173] Examples of the metal complex used as the host preferably have the following general formula:

[0174]

[0175] where Met is a metal; (Y 103 -Y 104 ) is a bidentate ligand, Y 103 and Y 104 are independently selected from C, N, O, P, and S; L 101is another ligand; k' is an integer value from 1 to the maximum number of ligands that can be attached to the metal; and k'+k" is the maximum number of ligands that can be attached to the metal.

[0176] In one aspect, the metal complex is:

[0177]

[0178] where (ON) is a bidentate ligand with a metal coordinated to O and N atoms.

[0179] In another aspect, Met is selected from Ir and Pt. In another aspect, (Y 103 -Y 104 ) is a carbene ligand.

[0180] Examples of organic compounds used as hosts are selected from the group consisting of aromatic hydrocarbon ring compounds such as benzene, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenanthrene, fluorene, pyrene, leturon, perylene and azulene; and the group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridyl indole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indole, oxazole, indoloxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, dibenzopyran, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine and selenophenodipyridine; and a group consisting of 2 to 10 cyclic structural units, which are groups of the same type or different types selected from aromatic hydrocarbon ring groups and aromatic heterocyclic groups, and are bonded to each other directly or via at least one of oxygen atoms, nitrogen atoms, sulfur atoms, silicon atoms, phosphorus atoms, boron atoms, chain structural units and aliphatic ring groups. Each option within each group may be unsubstituted or substituted with a substituent selected from the group consisting of deuterium, halide, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silanyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0181] In one aspect, the subject compound contains at least one of the following groups in the molecule:

[0182]

[0183] where R101 to R 107 Each of the following is independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silanyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, phosphino, and combinations thereof, and when it is an aryl or heteroaryl group, it has a similar definition to that of Ar above. k is an integer from 0 to 20 or from 1 to 20; k'" is an integer from 0 to 20. X 101 to X 108 is selected from C (including CH) or N.

[0184] Z 101 and Z 102 Selected from NR 101 , O or S.

[0185] 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 disclosing those materials:

[0186] EP2034538, EP2034538A, EP2757608, JP2007254297, KR20100079458, KR20120088644, KR20120129733, KR20130115564, TW201329200, US20030175553, US20050238919, US20060280965, US20090017330, US20090030202, US20090167162, US20090302743, US20090309488, US20100012931, US20100084966, US20100187984, US2010187984, US2012075273, US2012126221, US2013009543, US2013105787, US2013175519, US2014001446, US20140183503, US20140225088, US2014034914, US7154114, WO2001039234, WO2004093207, WO2005014551, WO2005089025, WO2006072002, WO2006114966, WO2007063754, WO2008056746, WO2009003898, WO2009003898, WO2009021126, WO2009063833, WO2009066778, WO2009066779, WO2009086028, WO2010056066, WO2010107244, WO2011081423, WO2011081431, WO2011086863, WO2012128298, WO2012133644, WO2012133649, WO2013024872, WO2013035275, WO2013081315, WO2013191404, WO2014142472.

[0187]

[0188]

[0189]

[0190]

[0191]

[0192] Emitter:

[0193] Emitter examples are not particularly limited, and any compound can be used so 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 emission via phosphorescence, fluorescence, thermally activated delayed fluorescence (i.e., TADF, also known as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0194] Non-limiting examples of emitter materials that can be combined with the materials disclosed herein for OLEDs are illustrated below along with references disclosing those materials: CN103694277, CN1696137, EB01238981, EP01239526, EP01961743, EP1239526, EP1244155, EP1642951, EP1647554, EP1841834, EP1841834B, EP2062907, EP2730583, JP2012074444, JP2013110263, JP4478555, KR1020090133652, KR20120032054, KR20130043460, TW201332980, US06699599, US06916554, US20010019782, US20020034656, US20030068526, US20030072964, US20030138657, US20050123788, US20050244673, US2005123791, US2005260449, US20060008670, US20060065890, US20060127696, US20060134459, US20060134462, US20060202194, US20060251923, US20070034863, US20070087321, US20070103060, US20070111026, US20070190359, US20070231600, US2007034863, US2007104979, US2007104980, US2007138437, US2007224450, US2007278936, US20080020237, US20080233410, US20080261076, US20080297033, US200805851, US2008161567, US2008210930, US20090039776, US20090108737, US20090115322, US20090179555, US2009085476, US2009104472, US20100090591, US20100148663, US20100244004, US20100295032, US2010102716, US2010105902, US2010244004, US2010270916, US20110057559, US20110108822,US20110204333, US2011215710, US2011227049, US2011285275, US2012292601, US20130146848, US2013033172, US2013165653, US2013181190, US2013334521, US20140246656, US2014103305, US6303238, US6413656, US6653654, US6670645, US6687266, US6835469, US6921915, US7279704, US7332232, US7378162, US7534505, US7675228, US7728137, US7740957, US7759489, US7951947, US8067099, US8592586, US8871361, WO06081973, WO06121811, WO07018067, WO07108362, WO07115970, WO07115981, WO08035571, WO2002015645, WO2003040257, WO2005019373, WO2006056418, WO2008054584, WO2008078800, WO2008096609, WO2008101842, WO2009000673, WO2009050281, WO2009100991, WO2010028151, WO2010054731, WO2010086089, WO2010118029, WO2011044988, WO2011051404, WO2011107491, WO2012020327, WO2012163471, WO2013094620, WO2013107487, WO2013174471, WO2014007565, WO2014008982, WO2014023377, WO2014024131, WO2014031977, WO2014038456, WO2014112450.

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201] HBL:

[0202] A hole blocking layer (HBL) can be used to reduce the number of holes and / or excitons that escape the emissive layer. The presence of such a blocking layer in the device can result in substantially higher efficiencies and / or longer lifetimes than similar devices lacking the blocking layer. Additionally, the blocking layer can serve to confine emission to the desired area of the OLED. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and or higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and or higher triplet energy than one or more of the hosts closest to the HBL interface.

[0203] In one aspect, the compounds used in the HBL contain the same molecule or the same functional group as the hosts described above.

[0204] In another aspect, the compounds used in the HBL contain at least one of the following groups in the molecule:

[0205]

[0206] where k is an integer from 1 to 20; L 101 is another ligand and k' is an integer from 1 to 3.

[0207] ETL:

[0208] An electron transport layer (ETL) can include a material capable of transporting electrons. The electron transport layer can be intrinsic (undoped) or doped. Doping can be used to enhance the conductivity. Examples of ETL materials are not particularly limited and can use any metal complex or organic compound as long as it is typically used to transport electrons.

[0209] In one aspect, the compounds used in the ETL contain at least one of the following groups in the molecule:

[0210]

[0211] where R 101 is selected from the group consisting of hydrogen, deuterium, a halogen, an alkyl group, a cycloalkyl group, a heteroalkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group, a silyl group, an alkenyl group, a cycloalkenyl group, a heteroalkenyl group, an alkynyl group, an aryl group, a heteroaryl group, an acyl group, a carbonyl group, a carboxyl group, an ester group, a nitrile group, an isonitrile group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, when it is an aryl or heteroaryl group, it has similar definitions to that of Ar described above. Ar1 to Ar 3 has a definition similar to the above Ar. k is an integer from 1 to 20. 101 to X 108 is selected from C (including CH) or N.

[0212] In another aspect, the metal complex used in the ETL contains, but is not limited to, the following general formula:

[0213]

[0214] wherein (O-N) or (N-N) is a bidentate ligand with a metal coordinated to atoms O, N or N, N; L 101 is another ligand; k' is an integer value from 1 to the maximum number of ligands that can be connected to the metal.

[0215] Non-limiting examples of ETL materials that can be combined with the materials disclosed herein for OLEDs are exemplified below along with references disclosing those materials: CN103508940, EP01602648, EP01734038, EP01956007, JP2004-022334, JP2005149918, JP2005-268199, KR0117693, KR20130108183, US20040036077, US20070104977, US2007018155, US20090101870, US20090115316, US20090140637, US20090179554, US2009218940, US2010108990, US2011156017, US2011210320, US2012193612, US2012214993, US2014014925, US2014014927, US20140284580, US6656612, US8415031, WO2003060956, WO2007111263, WO2009148269, WO2010067894, WO2010072300, WO2011074770, WO2011105373, WO2013079217, WO2013145667, WO2013180376, WO2014104499, WO2014104535.

[0216]

[0217]

[0218]

[0219] Charge generation layer (CGL)

[0220] In a tandem or stacked OLED, the CGL plays an essential role in performance, which consists of an n-doped layer and a p-doped layer for injecting electrons and holes, respectively. The electrons and holes are supplied by the CGL and electrodes. The consumed electrons and holes in the CGL are refilled by the electrons and holes injected from the cathode and anode, respectively; then, the ambipolar current gradually reaches a steady state. Typical CGL materials include n and p conductivity dopants used in transport layers.

[0221] In any of the above compounds used in each layer of an OLED device, the hydrogen atoms can be partially or fully deuterated. Thus, any specifically listed substituent (such as, but not limited to, methyl, phenyl, pyridyl, etc.) can be in its non-deuterated, partially deuterated, and fully deuterated forms. Similarly, substituent classes (such as, but not limited to, alkyl, aryl, cycloalkyl, heteroaryl, etc.) can also be in its non-deuterated, partially deuterated, and fully deuterated forms.

[0222] Experiment

[0223] Material synthesis

[0224] Unless otherwise specified, all reactions were carried out under nitrogen protection. All solvents of the reactions were anhydrous and used as received from commercial sources.

[0225] Synthesis of compound 3676

[0226] Synthesis of 4-(3,5-dimethylphenyl)-7-isopropylthieno[3,2-d]pyrimidine

[0227]

[0228] A flask was charged with 4-chloro-7-isopropylthieno[3,2-d]pyrimidine (4.50 g, 21.2 mmol), Pd(PPh3)4(0.73 g, 0.64 mmol), potassium carbonate (7.31 g, 52.9 mmol), tetrahydrofuran (THF) (200 ml), and water (50.0 ml). The mixture was degassed by bubbling nitrogen for 15 minutes, and then the reaction was heated to reflux overnight. The reaction was extracted with ethyl acetate and washed with brine, dried over sodium sulfate, filtered, and concentrated. The brown oil was purified with silica gel using DCM to 90 / 10 DCM / ethyl acetate solvent system. The orange oil was further purified with silica gel using 75 / 25 heptane / ethyl acetate solvent system to give 5.50 g of white solid in 90% yield.

[0229] Synthesis of Ir(III) dimer

[0230]

[0231] To a flask was added 4-(3,5-dimethylphenyl)-7-isopropylthieno[3,2- d]pyrimidine (3.07 g, 10.9 mmol) and dissolved in 2-ethoxyethanol (40 mL) and water (13 mL). The mixture was degassed by bubbling nitrogen for 15 minutes, then IrCl3H2O4 (1.15 g, 3.10 mmol) was added. The reaction was heated at 105 °C under nitrogen for 24 hours. The reaction was cooled to room temperature, diluted with 10 mL MeOH, filtered, and washed with MeOH to give 1.6 g of solid in 65% yield.

[0232] Synthesis of compound 3676

[0233]

[0234] To a flask was combined Ir(III) dimer (1.00 g, 0.63 mmol), 3,7- diethylnonane-4,6-dione (1.34 g, 6.33 mmol), and 2-ethoxyethanol (15 ml). Nitrogen was bubbled into the suspension for 15 minutes, and potassium carbonate (0.87 g, 6.33 mmol) was added. The reaction was stirred at room temperature overnight. The mixture was filtered through celite using dichloromethane (DCM), and the filtrate was concentrated. The solid was triturated in 100 mL MeOH, and the solid was filtered off. The solid was purified using silica gel (pre-treated with triethylamine) using 95 / 5 to 90 / 10 heptane / DCM to give 0.45 g of the title compound (37% yield).

[0235] Synthesis of compound 6796

[0236] Synthesis of 6,7-dichloro-4-(3,5-dimethylphenyl)thieno[3,2-d]pyrimidine

[0237]

[0238] A flask was charged with 4,6,7-trichlorothieno[3,2-d]pyrimidine (12.0 g, 50.1 mmol), (3,5-dimethylphenyl)boronic acid (8.27 g, 55.1 mmol), potassium carbonate (17.3 g, 125 mmol), THF (300 mL), and water (75 mL). The solution was purged with nitrogen for 15 minutes, then tetrakis(triphenylphosphine)palladium (1.74 g, 1.503 mmol) was added. The reaction was heated to reflux under nitrogen overnight. The reaction mixture was extracted with ethyl acetate (3 times), then washed with brine and water. The yellow solid was purified with silica gel using 90 / 10 heptane / EtOac as the solvent system to give a white solid. The sample was further purified with silica gel using DCM to 95 / 5 DCM / EtOac as the solvent system to give 8.4 g of white solid in 54% yield.

[0239] Synthesis of 4-(3,5-dimethylphenyl)-6,7-bis(3,3,3-trifluoropropyl)thieno[3,2- d]pyrimidine

[0240]

[0241] A flask was charged with 4,6,7-trichlorothieno[3,2-d]pyrimidine (12.0 g, 50.1 mmol), (3,5-dimethylphenyl)boronic acid (8.27 g, 55.1 mmol), potassium carbonate (17.3 g, 125 mmol), THF (300 mL), and water (75 mL). The solution was purged with nitrogen for 15 minutes, then tetrakis(triphenylphosphine)palladium (1.74 g, 1.503 mmol) was added. The reaction was heated to reflux under nitrogen overnight. The reaction mixture was extracted with ethyl acetate (3 times), then washed with brine and water. The yellow solid was purified with silica gel using 90 / 10 heptane / EtOac as the solvent system to give a white solid. The sample was further purified with silica gel using DCM to 95 / 5 DCM / EtOac as the solvent system to give 8.4 g of white solid in 54% yield.

[0242] Synthesis of Ir(III) dimer

[0243]

[0244] Combine 4-(3,5-dimethylphenyl)-6,7-bis(3,3,3-trifluoropropyl)thieno[3,2- d]pyrimidine (2.86 g, 6.61 mmol), 2-ethoxyethanol (24 mL), and water (8 mL) in a flask. Bubble nitrogen into the reaction for 15 minutes, then add IrCl3H8O4(0.70 g, 1.89 mmol). Heat the reaction at 105 °C under nitrogen overnight. Cool the reaction, and dilute with 10 mL MeOH, filter, and wash with MeOH to give 2.28 g (quantitative yield) of an orange-red solid.

[0245] Synthesis of compound 6796

[0246]

[0247] Combine Ir(III) dimer (2.10 g, 1.59 mmol), 3,7-diethyl-5-methylnonane-4,6-dione (4.0 ml, 15.9 mmol), and 2-ethoxyethanol (30 ml) in a flask. Bubble nitrogen into the suspension for 15 minutes, then add potassium carbonate (2.20 g, 15.9 mmol). Stir the reaction at room temperature overnight. After the reaction is complete, dilute the reaction in DCM, and filter through celite. Wet grind the red oil in 75 mL hot MeOH, cool to room temperature, and then filter. Purify the solid with silica gel (pre-treated with triethylamine) using a 95 / 5 to 85 / 15 heptane / DCM solvent system to give 1.41 g of the title compound (35% yield).

[0248] Synthesis of compound 6841

[0249] Synthesis of 6-bromo-4-(3,5-dimethylphenyl)-7-isopropylthieno[3,2-d]pyrimidine

[0250]

[0251] Add 4-(3,5-dimethylphenyl)-7-isopropylthieno[3,2-d]pyrimidine (5.00 g, 17.7 mmol) to an oven-dried flask. Evacuate the system and purge with nitrogen three times. Add THF (200 mL) and cool the solution to -70 °C, then add 2.5 M butyllithium (8.5 mL, 21.3 mmol) dropwise. Stir the reaction at this temperature for three hours, then add dibromomethane (1.0 mL, 19.5 mmol) dropwise. Stir the reaction at -70 °C for 30 minutes, then allow it to warm to room temperature and stir overnight. Quench the mixture with water and extract with ethyl acetate, washing twice with brine, dry over sodium sulfate, filter, and concentrate to an orange-yellow solid. Purify the crude product on silica gel using 95 / 5 to 90 / 10 heptane / EtOac solvent system to give an off-white solid. Repeat the silica gel purification using 97.5 / 2.5 to 95 / 5 heptane / EtOac solvent system to give 5.10 g of white solid in 80% yield.

[0252] Synthesis of 4-(3,5-dimethylphenyl)-7-isopropyl-6-(3,3,3-trifluoro-2,2- dimethylpropyl)thieno[3,2-d]pyrimidine

[0253]

[0254] Combine 6-bromo-4-(3,5-dimethylphenyl)-7-isopropylthieno[3,2-d]pyrimidine (4.50 g, 12.5 mmol), palladium(II) acetate (0.11 g, 0.50 mmol), and 2'-(dicyclohexylphosphino)-N2,N2,N6,N6-tetramethyl-[1,1'-biphenyl]-2,6-diamine (Cphos) (0.44 g, 1.00 mmol) in an oven-dried flask. Dissolve the solids in THF (50 mL) and stir the reaction for 15 minutes, then add (3,3,3-trifluoro-2,2-dimethylpropyl)zinc(II) bromide (110 ml, 24.9 mmol) via syringe and stir the mixture overnight. Quench the reaction with sodium bicarbonate solution, extract with ethyl acetate (3 times). Dry the combined organics over sodium sulfate, filter, and concentrate. Purify the crude product on silica gel using 85 / 15 heptane / ethyl acetate to give 5.0 g of a brown oil. Purify the product again on silica gel using 97.5 / 2.5 to 95 / 5 heptane / ethyl acetate to give 4.1 g of a clear oil that becomes a white solid in 80% yield.

[0255] Synthesis of Ir(III) dimer

[0256]

[0257] A flask was charged with 4-(3,5-dimethylphenyl)-7-isopropyl-6-(3,3,3-trifluoro-2,2- dimethylpropyl)thieno[3,2-d]pyrimidine (3.84 g, 9.44 mmol), 2-ethoxyethanol (34 mL), and water (11 mL). The mixture was degassed by bubbling nitrogen for 15 minutes, then IrCl3H2O4 (1.00 g, 2.70 mmol) was added. The reaction was heated at 105 °C for 24 hours. The reaction was cooled to room temperature, diluted with 30 ml MeOH, then the product was filtered and washed with MeOH to give 2.50 g (quantitative yield).

[0258] Synthesis of compound 6841

[0259]

[0260] A flask was charged with Ir(III) dimer (2.00 g, 1.58 mmol), 3,7-diethyl-5- methylnonane-4,6-dione (3.58 g, 15.8 mmol), and 2-ethoxyethanol (30 ml). Nitrogen was bubbled into the suspension for 15 minutes, and then potassium carbonate (2.18 g, 15.8 mmol) was added. The reaction was stirred at room temperature overnight. The mixture was filtered through celite using DCM, and the filtrate was concentrated. The solid was trituration in 100 mL MeOH, and the solid was filtered off. The solid was purified using 90 / 10 heptane / DCM on silica gel (pre-treated with triethylamine) to give 1.20 g of the title compound (31% yield).

[0261] Synthesis of compound 6836

[0262]

[0263] A flask was charged with Ir(III) dimer (1.80 g, 1.14 mmol), 3,7-diethyl-5- methylnonane-4,6-dione (2.9 mL, 11.4 mmol), and 2-ethoxyethanol (25 ml). Nitrogen was bubbled into the suspension for 15 minutes, and then potassium carbonate (1.57 g, 11.4 mmol) was added. The reaction was stirred at room temperature overnight. The mixture was filtered through celite using DCM, and the filtrate was concentrated. The solid was trituration in 100 mL MeOH, and the solid was filtered off. The crude product was purified using 95 / 5 to 90 / 10 heptane / DCM on silica gel (pre-treated with triethylamine) to give 1.20 g of the title compound (54% yield).

[0264] Synthesis of comparative compound 1

[0265] Synthesis of Ir(III) dimer

[0266]

[0267] 7-(3,5-dimethylphenyl)thieno[2,3-c]pyridine (2.063 g, 8.62 mmol) was dissolved in ethoxyethanol (26 mL) and water (9 mL). The mixture was degassed for 15 minutes by bubbling nitrogen, and then iridium (III) chloride trihydrate (0.80 g, 2.269 mmol) was added and the reaction was heated at 105 ° C for 24 hours. The reaction was cooled to room temperature, diluted with 10 mL of MeOH, filtered, and washed with MeOH to give 1.20 g (75% yield) of product.

[0268] Synthesis of comparative compound 1

[0269]

[0270] Ir (III) dimer (1.15g, 0.82mmol), 3,7-diethyl nonane-4,6-dione (1.30g, 6.12mmol) and 2-ethoxyethanol (14mL) are combined, and the mixture is purged with nitrogen for 15 minutes. Potassium carbonate (0.85g, 6.12mmol) is added, and the reactants are stirred at room temperature overnight. The mixture is dissolved in DCM and filtered through a celite pad. The solvent is rotary evaporated, and the mixture is wet-ground with methanol and filtered. The crude material is further purified using a heptane / DCM (95 / 5) solvent system by column chromatography (pre-treated with triethylamine). The product is then recrystallized from a DCM / MeOH mixture to obtain 1.30g (90% yield) of orange powder.

[0271] Device Examples

[0272] All example devices were passed through a high vacuum (<10 -7 Torr) thermal evaporation manufacturing. The anode electrode is The cathode is made of indium tin oxide (ITO). Liq (8-hydroxyquinoline lithium) followed by All devices were immediately packaged in a nitrogen glove box (<1 ppm H2O and O2) with epoxy-sealed glass lids after fabrication, and a moisture absorber was incorporated into the packaging. The organic stack of the device example consisted of the following, starting from the ITO surface: LG101 (purchased from LG Chem) was used as a hole injection layer (HIL); The HTM serves as the hole transport layer (HTL); Compound H as the host, a stability dopant (SD) (18%) and Comparative Compound 1 or Compounds 3676, 6836 and 6841 as the emitter (3%) in the EML; Compound H as the blocking layer; and Liq (8-hydroxyquinolinolato lithium) doped with 40% ETM as the ETL. The emitters were chosen to provide the desired color, efficiency and lifetime. Stability dopants (SD) were added to the electron transporting host to help transport positive charges in the emission layer. Comparative Example devices were fabricated similarly to the Device Examples, except that Comparative Compound 1 was used as the emitter in the EML. The device layer thicknesses and materials are shown in Table 3 below. The chemical structures of the materials used in the devices are shown in Table 5 below.

[0273] Device performance data is summarized in Table 4 below. The present compounds have much longer lifetimes compared to Comparative Compound 1. In addition, Compounds 3676, 6836 and 6841 have superior performance in color saturation compared to Comparative Compound 1, with a red shift of 28 to 38 nm observed. In addition, the present compounds give similar or higher EQE compared to Comparative Compound 1.

[0274] Table 3. Device layer materials and thicknesses

[0275]

[0276] Table 4. Device performance data

[0277]

[0278] Table 5. Materials used in OLED devices

[0279]

[0280]

[0281] It should be 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 deviating from the spirit of the invention. The present invention as claimed is therefore directed to the particular examples and preferred embodiments described herein, as well as modifications that can occur to persons skilled in the art, as well as combinations of the teachings of the present disclosure with teachings of the patents cited above. It is understood that no theory of operation is intended to limit the present invention.

Claims

1. A compound comprising a ligand L of formula I A : wherein Ring A is a 6-membered carbon ring; wherein the ligand L A yes: wherein R is fused to ring B and has the structure of Formula II: The wavy line represents the bond to ring B; where R 1 represents a mono-, di-, tri- or tetra-substituted group or no substituent; where R 2 represents a monosubstituted group, a disubstituted group, or no substitution; where X 1 、X 2 、X 3 and X 4 each independently carbon or nitrogen; where X 1 、X 2 、X 3 and X 4 At least one of is nitrogen; At least two adjacent X 1 、X 2 、X 3 and X 4 is carbon and fused to R; wherein X is selected from the group consisting of BR', NR', PR', O, S, Se, C=O, S=O, SO2, CR'R", SiR'R" and GeR'R"; where R 1 、R 2 、R 3 、R 4 , R' and R" are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silanyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, phosphino, and combinations thereof; and wherein any two adjacent substituents are optionally linked to form a ring; where R 3 and R 4 At least one of comprises a chemical group selected from the group consisting of an alkyl group, a cycloalkyl group, a partially fluorinated alkyl group, a partially fluorinated cycloalkyl group, and combinations thereof; wherein the ligand L A Coordinated to metal M; wherein M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu; wherein the ligand L A optionally linked to other ligands to comprise tridentate, tetradentate, pentadentate, or hexadentate ligands; and Wherein M is optionally coordinated to other ligands, where R 3 and R 4 Not hydrogen.

2. The compound according to claim 1, wherein the ligand L A Select from the group consisting of:

3. The compound according to claim 1, wherein R 3 and R 4 At least one of is a chemical group selected from the group consisting of a partially fluorinated alkyl group, a partially fluorinated cycloalkyl group, and combinations thereof.

4. The compound according to claim 1, wherein R 3 and R 4 At least one of is selected from the group consisting of:

5. The compound according to claim 1, wherein R 3 With R 4 connected to form a ring structure selected from the group consisting of:

6. The compound according to claim 1, wherein the ligand L A Select from the group consisting of:

7. The compound according to claim 4, wherein the ligand L A Selected from the group consisting of: L defined as follows A1 to L A750 : L A1 to L A375 Based on the structure of Formula IV, where R 3 、F 4 and X is defined as: And L A376 to L A750 Based on the structure of Formula V, where R 3 、R 4 and X is defined as: where R B1 to R B4 Has the following structure:

8. The compound according to claim 1, wherein the compound has a structure of formula III (L A ) n Ir(L B ) 3-n , where L B is a bidentate ligand and n is 1, 2 or 3.

9. The compound according to claim 8, wherein the ligand L B Select from the group consisting of:

10. The compound of claim 7, wherein the compound is selected from the group consisting of: Compound 1 to Compound 12,750; Wherein each compound x has the formula Ir(L Ak )2(L Bj ); wherein x=750j+k-750, k is an integer from 1 to 750, and j is an integer from 1 to 17; and wherein the ligand L B1 to L B17 The definition is as follows:

11. A first device comprising a first organic light-emitting device, wherein the first organic light-emitting device comprises: anode; cathode; and An organic layer disposed between the anode and the cathode, comprising the compound of any one of claims 1-10.

12. A formulation comprising a compound according to any one of claims 1-10.

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