Organic light emitting diode materials

Abstract
The present invention relates to novel organic compounds containing a triphenylene and a carbazole. The compounds are useful for organic light-emitting diodes. The compounds are also useful for charge-transport and charge-blocking layers, and as hosts in the light-emissive layer for organic light emitting devices (OLEDs).
Description

The claimed invention was made by, on behalf of, and/or in connection with one or more of the following parties to a joint university corporation research agreement: Regents of the University of Michigan, Princeton University, The University of Southern California, and the Universal Display Corporation. The 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 undertaken within the scope of the agreement.


FIELD OF THE INVENTION

The present invention relates to novel organic compounds comprising a triphenylene and a carbazole. The compounds are useful as host materials for organic light-emitting diodes. The compounds are also useful for charge-transport and charge-blocking layers, and as hosts in the light-emissive layer for organic light emitting devices (OLEDs).


BACKGROUND

Opto-electronic devices that make use of organic materials are becoming increasingly desirable for a number of reasons. Many of the materials used to make such devices are relatively inexpensive, so organic opto-electronic devices have the potential for cost advantages over inorganic devices. In addition, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications such as fabrication on a flexible substrate. Examples of organic opto-electronic devices include organic light emitting devices, organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, the organic materials may have performance advantages over conventional materials.


For example, the wavelength at which an organic emissive layer emits light may generally be readily tuned with appropriate dopants.


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 applications such as flat panel displays, illumination, and backlighting. Several OLED materials and configurations are described in U.S. Pat. Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.


One application for phosphorescent emissive molecules is a full color display. Industry standards for such a display call for pixels adapted to emit particular colors, referred to as “saturated” colors. In particular, these standards call for saturated red, green, and blue pixels. Color may be measured using CIE coordinates, which are well known to the art.


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




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In this, and later figures herein, we depict the dative bond from nitrogen to metal (here, Ir) as a straight line.


As used herein, the term “organic” includes polymeric materials as well as small molecule organic materials that may be used to fabricate organic opto-electronic devices. “Small molecule” refers to any organic material that is not a polymer, and “small molecules” may actually be quite large. Small molecules may include repeat 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 may also be incorporated into polymers, for example as a pendent group on a polymer backbone or as a part of the backbone. Small molecules may also serve as the core moiety of a dendrimer, which consists of a series of chemical shells built on the core moiety. The core moiety of a dendrimer may be a fluorescent or phosphorescent small molecule emitter. A dendrimer may be a “small molecule,” and it is believed that all dendrimers currently used in the field of OLEDs are small molecules.


As used herein, “top” means furthest away from the substrate, while “bottom” means closest to the substrate. Where a first layer is described as “disposed over” a second layer, the first layer is disposed further away from substrate. There may be other layers between the first and second layer, unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “disposed over” an anode, even though there are various organic layers in between.


As used herein, “solution processable” means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium, either in solution or suspension form.


A ligand may be referred to as “photoactive” when it is believed that the ligand directly contributes to the photoactive properties of an emissive material. A ligand may be referred to as “ancillary” when it is believed that the ligand does not contribute to the photoactive properties of an emissive material, although an ancillary ligand may alter the properties of a photoactive ligand.


As used herein, and as would be generally understood by one 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. Since ionization potentials (IP) are measured as a negative energy relative to a vacuum level, a higher HOMO energy level corresponds to an IP having a smaller absolute value (an IP that is less negative). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) having a smaller absolute value (an EA that is less negative). 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.


As used herein, and as would be generally understood by one 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 further 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.


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


BRIEF SUMMARY OF THE INVENTION

A new class of compounds containing a triphenylene and a carbazole is provided.


The present invention provides a compound having formula I:




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wherein at least one of R3a, R3b, R3c, or R3d has formula II:




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wherein at least one of R4a, R4b, R4c, R5a, R5b, R5c, or R5d has formula III:

-L2-G  (III);


wherein L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, nitrile, and combinations thereof;


wherein X is selected from the group consisting of O, S, and Se;


wherein G is a carbazole which may be optionally substituted;


wherein R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;


wherein R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and


wherein R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, G is connected to L2 at the nitrogen atom of the 9-position of carbazole.


In some embodiments, G is connected to L2 at a carbon atom at the 1-, 2-, 3-, or 4-position of carbazole.


In some embodiments, L1 is a direct bond.


In some embodiments, one of R4b, R5a, or R5c is L2-G.


In some embodiments, L1 and L2 are independently selected from the group consisting of a direct bond, a phenyl group, and a biphenyl group.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are hydrogen, R3a, R3b, R3c, and R3d that are not formula II are hydrogen, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are hydrogen.


In some embodiments, X is O.


In some embodiments, X is S.


In some embodiments, X is S, L1 and L2 are a direct bond, and R5a is L2-G.


In some embodiments, X is S, L1 is a direct bond, L2 is phenyl, and R5a is L2-G.


In some embodiments, G is substituted with one or more substituents selected from the group consisting of deuterium, hydrogen, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphine, and combinations thereof.


In some embodiments, the compound of the present invention has formula IV:




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In some embodiments, the compound of the present invention has formula V:




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In some embodiments, the compound is selected from the group consisting of:




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The present invention also provides an organic light emitting device. The organic light emitting device comprises:


an anode;


a cathode;


an organic layer, disposed between the anode and the cathode, wherein the organic layer comprises a compound having formula I:




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wherein at least one of R3a, R3b, R3c, or R3d has formula II:




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wherein at least one of R4a, R4b, R4c, R5a, R5b, R5c, or R5d has formula III:

-L2-G  (III);


wherein L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, nitrile, and combinations thereof;


wherein X is selected from the group consisting of O, S, and Se;


wherein G is a carbazole which may be optionally substituted; and


wherein R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;


wherein R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and


wherein R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


The present invention also provides a formulation comprising a compound of formula I.





BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments of the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention.



FIG. 1 shows an organic light emitting device.



FIG. 2 shows an inverted organic light emitting device that does not have a separate electron transport layer.



FIG. 3 shows a compound of Formula IV.





DETAILED DESCRIPTION

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 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. Light is emitted when the exciton relaxes via a photoemissive mechanism. In some cases, the exciton may be localized on an excimer or an exciplex. Non-radiative mechanisms, such as thermal relaxation, may also occur, but are generally considered undesirable.


The initial OLEDs used emissive molecules that emitted light from their singlet states (“fluorescence”) as disclosed, for example, in U.S. Pat. No. 4,769,292, which is incorporated by reference in its entirety. Fluorescent emission generally occurs in a time frame of less than 10 nanoseconds.


More recently, OLEDs having 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, 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 more detail in U.S. Pat. No. 7,279,704 at cols. 5-6, which are incorporated by reference.



FIG. 1 shows an organic light emitting device 100. 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 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 more detail in U.S. Pat. No. 7,279,704 at cols. 6-10, which are incorporated by reference.


More examples for each of these layers are available. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of emissive and host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entireties, disclose examples of cathodes including compound cathodes having a thin layer of metal such as Mg:Ag with an overlying transparent, electrically-conductive, sputter-deposited ITO layer. The theory and use of blocking layers is described in more detail in U.S. Pat. No. 6,097,147 and U.S. Patent Application Publication No. 2003/0230980, which are incorporated by reference 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 may be found in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety.



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 may be fabricated by depositing the layers described, in order. Because the most common OLED configuration has a cathode disposed over the anode, and device 200 has cathode 215 disposed under anode 230, device 200 may 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 one example of how some layers may be omitted from the structure of device 100.


The simple layered structure illustrated in FIGS. 1 and 2 is provided by way of non-limiting example, and it is understood that embodiments of the invention may be used in connection with a wide variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. Functional OLEDs may be achieved by combining the various layers described in different 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. Although many of the examples provided herein describe various layers as comprising a single material, it is understood that combinations of materials, such as a mixture of host and dopant, or more generally a mixture, may be used. Also, the layers may 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 some embodiments, an OLED may be described as having an “organic layer” disposed between a cathode and an anode. This organic layer may comprise a single layer, or may further comprise multiple layers of different organic materials as described, for example, with respect to FIGS. 1 and 2.


Structures and materials not specifically described may also be used, such as OLEDs comprised of polymeric materials (PLEDs) such as disclosed in U.S. Pat. No. 5,247,190 to Friend et al., which is incorporated by reference in its entirety. By way of further example, OLEDs 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. The OLED structure may deviate from the simple layered structure illustrated in FIGS. 1 and 2. For example, the substrate may include an angled reflective surface to improve out-coupling, such as a mesa structure as described in U.S. Pat. No. 6,091,195 to Forrest et al., and/or a pit structure as described in U.S. Pat. No. 5,834,893 to Bulovic et al., which are incorporated by reference in their entireties.


Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For the organic layers, preferred methods include thermal evaporation, ink-jet, such as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, which are incorporated by reference in their entireties, organic vapor phase deposition (OVPD), such as described in U.S. Pat. No. 6,337,102 to Forrest et al., which is incorporated by reference in its entirety, and deposition by organic vapor jet printing (OVJP), such 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 carried out in nitrogen or an inert atmosphere. For the other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding such as described in U.S. Pat. Nos. 6,294,398 and 6,468,819, which are incorporated by reference in their entireties, and patterning associated with some of the deposition methods such as ink-jet and OVJP. Other methods may also be used. The materials to be deposited may be modified to make them compatible with a particular deposition method. For example, substituents such as alkyl and aryl groups, branched or unbranched, and preferably containing at least 3 carbons, may be used in small molecules to enhance their ability to undergo solution processing. Substituents having 20 carbons or more may be used, and 3-20 carbons is a preferred range. Materials with asymmetric structures may have better solution processability than those having symmetric structures, because asymmetric materials may have a lower tendency to recrystallize. Dendrimer substituents may be used to enhance the ability of small molecules to undergo solution processing.


Devices fabricated in accordance with embodiments of the present invention may further optionally comprise 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, vapor and/or gases, etc. The barrier layer may be deposited over, under or next to a substrate, an electrode, or over any other parts of a device including an edge. The barrier layer may comprise 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 as well as compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate an inorganic or an organic compound or both. The preferred barrier layer comprises a mixture of a polymeric material and a non-polymeric material as described in U.S. Pat. No. 7,968,146, PCT Pat. Application Nos. PCT/US2007/023098 and PCT/US2009/042829, which are herein incorporated by reference in their entireties. To be considered a “mixture”, the aforesaid polymeric and non-polymeric materials comprising the barrier layer should be deposited under the same reaction conditions and/or at the same time. The weight ratio of polymeric to non-polymeric material may be in the range of 95:5 to 5:95. The polymeric material and the non-polymeric material may be created from the same precursor material. In one example, the mixture of a polymeric material and a non-polymeric material consists essentially of polymeric silicon and inorganic silicon.


Devices fabricated in accordance with embodiments of the invention may be incorporated into a wide variety of consumer products, including flat panel displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads up displays, fully transparent displays, flexible displays, laser printers, telephones, cell phones, personal digital assistants (PDAs), laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicles, a large area wall, theater or stadium screen, or a sign. Various control mechanisms may be used to control devices fabricated in accordance with the present invention, including passive matrix and active matrix. Many of the devices are intended for use in a temperature range comfortable to humans, such as 18 degrees C to 30 degrees C, and more preferably at room temperature (20-25 degrees C), but could be used outside this temperature range, for example, from −40 degree C to +80 degrees C.


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 employ the materials and structures. More generally, organic devices, such as organic transistors, may employ the materials and structures.


The term “halo” or “halogen” as used herein includes fluorine, chlorine, bromine, and iodine.


The term “alkyl” as used herein contemplates both straight and branched chain alkyl radicals. Preferred alkyl groups are those containing from one to fifteen carbon atoms and includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, and the like. Additionally, the alkyl group may be optionally substituted.


The term “cycloalkyl” as used herein contemplates cyclic alkyl radicals. Preferred cycloalkyl groups are those containing 3 to 7 carbon atoms and includes cyclopropyl, cyclopentyl, cyclohexyl, and the like. Additionally, the cycloalkyl group may be optionally substituted.


The term “alkenyl” as used herein contemplates both straight and branched chain alkene radicals. Preferred alkenyl groups are those containing two to fifteen carbon atoms. Additionally, the alkenyl group may be optionally substituted.


The term “alkynyl” as used herein contemplates both straight and branched chain alkyne radicals. Preferred alkyl groups are those containing two to fifteen carbon atoms. Additionally, the alkynyl group may be optionally substituted.


The terms “aralkyl” or “arylalkyl” as used herein contemplates an alkyl group that has as a substituent an aromatic group. Additionally, the aralkyl group may be optionally substituted.


The term “heterocyclic group” as used herein contemplates non-aromatic cyclic radicals. Preferred heterocyclic groups are those containing 3 or 7 ring atoms which includes at least one hetero atom, and includes cyclic amines such as morpholino, piperdino, pyrrolidino, and the like, and cyclic ethers, such as tetrahydrofuran, tetrahydropyran, and the like. Additionally, the heterocyclic group may be optionally substituted.


The term “aryl” or “aromatic group” as used herein contemplates single-ring groups and polycyclic ring systems. The polycyclic rings may have two or more rings in which two carbons are common by two adjoining rings (the rings are “fused”) wherein at least one of the rings is aromatic, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. Additionally, the aryl group may be optionally substituted.


The term “heteroaryl” as used herein contemplates single-ring hetero-aromatic groups that may include from one to three heteroatoms, for example, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, triazole, pyrazole, pyridine, pyrazine and pyrimidine, and the like. The term heteroaryl also includes polycyclic hetero-aromatic systems having two or more rings in which two atoms are common to two adjoining rings (the rings are “fused”) wherein at least one of the rings is a heteroaryl, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. Additionally, the heteroaryl group may be optionally substituted.


The alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclic group, aryl, and heteroaryl may be optionally substituted with one or more substituents selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


As used herein, the term “substituted” indicates that a substituent other than hydrogen is bonded to the relevant carbon or nitrogen atom. Thus, where R1 is mono-substituted, then one R1 must be other than hydrogen. Similarly, where R1 is di-substituted, then two of R1 must be other than hydrogen. Similarly, where R1 “represents no substitution,” R1 is hydrogen for all available positions.


The “aza” designation in the fragments described herein, i.e., aza-dibenzofuran, aza-dibenzonethiophene, etc. means that one or more of the C—H groups in the respective fragment can be replaced by a nitrogen atom, for example, and without any limitation, azatriphenylene encompasses both dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. One of ordinary skill in the art can readily envision other nitrogen analogs of the aza-derivatives described above, and all such analogs are intended to be encompassed by the terms as set forth herein.


It is to be understood that when a molecular fragment is described as being a substituent or otherwise attached to another moiety, its name may be written as if it were a fragment (e.g. naphthyl, dibenzofuryl) or as if it were the whole molecule (e.g., naphthalene, dibenzofuran). As used herein, these different ways of designating a substituent or attached fragment are considered to be equivalent.


A wide variety of carbazole-containing compounds have been developed as organic electroluminescent materials. Depending on the unique ways building blocks are connected, these compounds have different energy levels, molecular packing, and charge-transport properties, all of which heavily influence device performance. This invention discloses a new class of compounds comprising a triphenylene and a carbazole. Unexpectedly, phosphorescent OLED devices using the compounds of the invention as host materials demonstrate superior stability compared to the compounds reported in the literature.


In some embodiments, a compound having formula I:




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is provided. In the compound of formula I, at least one of R3a, R3b, R3c, or R3d has formula II:




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at least one of R4a, R4b, R4c, R5a, R5b, R5c, or R5d has formula III:

-L2-G  (III);

L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, nitrile, and combinations thereof; X is selected from the group consisting of O, S, and Se; G is a carbazole which may be optionally substituted; R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, G is connected to L2 at the nitrogen atom of the 9-position of carbazole.


In some embodiments, G is connected to L2 at a carbon atom at the 1-, 2-, 3-, or 4-position of carbazole.


In some embodiments, L1 is a direct bond.


In some embodiments, one of R4b, R5a, or R5c is L2-G.


In some embodiments, L1 and L2 are independently selected from the group consisting of a direct bond, a phenyl group, and a biphenyl group.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are hydrogen, R3a, R3b, R3c, and R3d that are not formula II are hydrogen, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are hydrogen.


In some embodiments, X is O.


In some embodiments, X is S.


In some embodiments, X is S, L1 and L2 are a direct bond, and R5a is L2-G.


In some embodiments, X is S, L1 is a direct bond, L2 is phenyl, and R5a is L2-G.


In some embodiments, G is substituted with one or more substituents selected from the group consisting of deuterium, hydrogen, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphine, and combinations thereof.


In some embodiments, a compound having formula IV:




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is provided. In the compound of formula IV, at least one of R4a, R4b, R4c, R5a, R5b, R5c, or R5d has formula:

-L2-G  (III);

L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, nitrile, and combinations thereof; X is selected from the group consisting of O, S, and Se; G is a carbazole which may be optionally substituted; R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, and R3d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, G is connected to L2 at the nitrogen atom of the 9-position of carbazole.


In some embodiments, G is connected to L2 at a carbon atom at the 1-, 2-, 3-, or 4-position of carbazole.


In some embodiments, L1 is a direct bond.


In some embodiments, one of R4b, R5a, or R5c is L2-G.


In some embodiments, L1 and L2 are independently selected from the group consisting of a direct bond, a phenyl group, and a biphenyl group.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, and R3d are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, and R3d are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, and R3d are hydrogen and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are hydrogen.


In some embodiments, X is O.


In some embodiments, X is S.


In some embodiments, X is S, L1 and L2 are a direct bond, and R5a is L2-G.


In some embodiments, X is S, L1 is a direct bond, L2 is phenyl, and R5a is L2-G.


In some embodiments, G is substituted with one or more substituents selected from the group consisting of deuterium, hydrogen, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphine, and combinations thereof.


In some embodiments, a compound having formula V:




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is provided. In the compound of formula V, L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, and combinations thereof; X is selected from the group consisting of O, S, and Se; G is a carbazole which may be optionally substituted; R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, R3d, R4a, R4b, R4c, R5b, R5c, and R5d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, G is connected to L2 at the nitrogen atom of the 9-position of carbazole.


In some embodiments, G is connected to L2 at a carbon atom at the 1-, 2-, 3-, or 4-position of carbazole.


In some embodiments, L1 is a direct bond.


In some embodiments, L1 and L2 are independently selected from the group consisting of a direct bond, a phenyl group, and a biphenyl group.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, R3d, R4a, R4b, R4c, R5b, R5c, and R5d are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, R3d, R4a, R4b, R4c, R5b, R5c, and R5d are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof.


In some embodiments, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, R3d, R4a, R4b, R4c, R5b, R5c, and R5d are hydrogen.


In some embodiments, X is O.


In some embodiments, X is S.


In some embodiments, X is S and L1 and L2 are a direct bond.


In some embodiments, X is S, L1 is a direct bond, and L2 is phenyl.


In some embodiments, G is substituted with one or more substituents selected from the group consisting of deuterium, hydrogen, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphine, and combinations thereof.


In some embodiments, the compound is selected from the group consisting of:




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In some embodiments, an organic light emitting device is provided. In some embodiments, the organic light emitting device comprises:


an anode;


a cathode;


an organic layer, disposed between the anode and the cathode, wherein the organic layer comprises a compound having formula I:




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wherein at least one of R3a, R3b, R3c, or R3d has formula II:




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wherein at least one of R4a, R4b, R4c, R5a, R5b, R5c, or R5d has formula II:

-L2-G  (III);


wherein L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, nitrile, and combinations thereof; wherein X is selected from the group consisting of O, S, and Se; wherein G is a carbazole which may be optionally substituted; wherein R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; wherein R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and wherein R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, an organic light emitting device is provided. In some embodiments, the organic light emitting device comprises:


an anode;


a cathode;


an organic layer, disposed between the anode and the cathode, wherein the organic layer comprises a compound having formula IV:




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wherein at least one of R4a, R4b, R4c, R5a, R5b, R5c, or R5d has formula III:

-L2-G  (III);

L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, and combinations thereof; X is selected from the group consisting of O, S, and Se; G is a carbazole which may be optionally substituted; R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, and R3d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, an organic light emitting device is provided. In some embodiments, the organic light emitting device comprises:


an anode;


a cathode;


an organic layer, disposed between the anode and the cathode, wherein the organic layer comprises a compound having formula V:




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L1 and L2 are independently selected from the group consisting of a direct bond, an aryl group having from 6-30 carbon atoms, a heteroaryl group having from 3-30 carbon atoms, and combinations thereof; wherein the aryl group and the heteroaryl group are optionally further substituted with one or more groups selected from hydrogen, deuterium, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, nitrile, and combinations thereof; X is selected from the group consisting of O, S, and Se; G is a carbazole which may be optionally substituted; R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b, R3d, R4a, R4b, R4c, R5b, R5c, and R5d are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, the organic layer of the device is an emissive layer and the compound of formula I is a host. In some embodiments, the organic layer of the device is an emissive layer and the compound of formula IV is a host. In some embodiments, the organic layer of the device is an emissive layer and the compound of formula V is a host.


In some embodiments, the organic layer of the device further comprises a phosphorescent emissive dopant. In some embodiments, the phosphorescent emissive dopant is a transition metal complex having at least one ligand or part of the ligand if the ligand is more than bidentate selected from the group consisting of:




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wherein Ra, Rb, Rc, and Rd may represent mono, di, tri, or tetra substitution, or no substitution; and wherein Ra, Rb, Rc, and Rd are independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and wherein two adjacent substituents of Ra, Rb, Rc, and Rd are optionally joined to form a fused ring or form a multidentate ligand.


In some embodiments, the organic layer of the device is a blocking layer and the compound is a blocking material in the organic layer.


In some embodiments, the device is a consumer product. In some embodiments, the device is an organic light-emitting device. In some embodiments, the device comprises a lighting panel.


In some embodiments, the compounds described herein are provided in a formulation with other materials present in the device. For example, the compounds of the invention may be provided in a formulation in conjunction with a wide variety of hosts, transport layers, blocking layers, injection layers, electrodes, or other layers.


In some embodiments, a formulation comprising a compound of formula I is provided. In some embodiments, a formulation comprising a compound of formula IV is provided. In some embodiments, a formulation comprising a compound of formula V is provided.


Combination with Other Materials


The materials described herein as useful for a particular layer in an organic light emitting device may be used in combination with a wide variety of other materials present in the device. For example, emissive dopants disclosed herein may 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 referred to below are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.


HIL/HTL:


A hole injecting/transporting material to be used in the present invention is not particularly limited, and any compound may be used as long as the compound is typically used as a hole injecting/transporting material. Examples of the material include, but are not limited to: a phthalocyanine or porphyrin derivative; an aromatic amine derivative; an indolocarbazole derivative; a polymer containing fluorohydrocarbon; a polymer with conductivity dopants; a conducting polymer, such as PEDOT/PSS; a self-assembly monomer derived from compounds such as phosphonic acid and silane derivatives; a metal oxide derivative, such as MoOx; a p-type semiconducting organic compound, such as 1,4,5,8,9,12-Hexaazatriphenylenehexacarbonitrile; a metal complex, and cross-linkable compounds.


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




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Each of Ar1 to Ar9 is selected from the group consisting aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene; group consisting aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and group consisting 2 to 10 cyclic structural units which are groups of the same type or different types selected from the aromatic hydrocarbon cyclic group and the aromatic heterocyclic group and are bonded to each other directly or via at least one of oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit and the aliphatic cyclic group. Wherein each Ar is further substituted by a substituent selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, Ar1 to Ar9 is independently selected from the group consisting of:




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k is an integer from 1 to 20; X101 to X108 is C (including CH) or N; Z101 is NAr1, O, or S; Ar1 has the same group defined above.


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




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Met is a metal; (Y101-Y102) is a bidentate ligand, Y101 and Y102 are independently selected from C, N, O, P, and S; L101 is an another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal; and k′+k″ is the maximum number of ligands that may be attached to the metal.


In some embodiments, (Y101-Y102) is a 2-phenylpyridine derivative.


In some embodiments, (Y101-Y102) is a carbene ligand.


In some embodiments, Met is selected from Ir, Pt, Os, and Zn.


In a further aspect, the metal complex has a smallest oxidation potential in solution vs. Fc+/Fc couple less than about 0.6 V.


Host:


The light emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as light emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complexes or organic compounds may be used as long as the triplet energy of the host is larger than that of the dopant. While the Table below categorizes host materials as preferred for devices that emit various colors, any host material may be used with any dopant so long as the triplet criteria is satisfied.


Examples of metal complexes used as host are preferred to have the following general formula:




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Met is a metal; (Y103-Y104) is a bidentate ligand, Y103 and Y104 are independently selected from C, N, O, P, and S; L101 is an another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal; and k′+k″ is the maximum number of ligands that may be attached to the metal.


In some embodiments, the metal complexes are:




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(O—N) is a bidentate ligand, having metal coordinated to atoms O and N.


In some embodiments, Met is selected from Ir and Pt.


In a further aspect, (Y103-Y104) is a carbene ligand.


Examples of organic compounds used as host are selected from the group consisting aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene; group consisting aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and group consisting 2 to 10 cyclic structural units which are groups of the same type or different types selected from the aromatic hydrocarbon cyclic group and the aromatic heterocyclic group and are bonded to each other directly or via at least one of oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit and the aliphatic cyclic group. Wherein each group is further substituted by a substituent selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.


In some embodiments, the host compound contains at least one of the following groups in the molecule:




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R101 to R107 is independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, when it is aryl or heteroaryl, it has the similar definition as Ar's mentioned above.


k is an integer from 1 to 20; k″′ is an integer from 0 to 20.


X101 to X108 is selected from C (including CH) or N.


Z101 and Z102 is selected from NR101, O, or S.


HBL:


A hole blocking layer (HBL) may be used to reduce the number of holes and/or excitons that leave the emissive layer. The presence of such a blocking layer in a device may result in substantially higher efficiencies as compared to a similar device lacking a blocking layer. Also, a blocking layer may be used to confine emission to a desired region of an OLED.


In some embodiments, compound used in HBL contains the same molecule or the same functional groups used as host described above.


In some embodiments, compound used in HBL contains at least one of the following groups in the molecule:




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k is an integer from 1 to 20; L101 is an another ligand, k′ is an integer from 1 to 3.


ETL:


Electron transport layer (ETL) may include a material capable of transporting electrons. Electron transport layer may be intrinsic (undoped), or doped. Doping may be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complexes or organic compounds may be used as long as they are typically used to transport electrons.


In some embodiments, compound used in ETL contains at least one of the following groups in the molecule:




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R101 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, when it is aryl or heteroaryl, it has the similar definition as Ar's mentioned above.


Ar1 to Ar3 has the similar definition as Ar's mentioned above.


k is an integer from 1 to 20.


X101 to X108 is selected from C (including CH) or N.


In some embodiments, the metal complexes used in ETL contains, but are not limited to the following general formula:




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(O—N) or (N—N) is a bidentate ligand, having metal coordinated to atoms O, N or N, N; L101 is another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal.


In any above-mentioned compounds used in each layer of the OLED device, the hydrogen atoms can be partially or fully deuterated. Thus, any specifically listed substituent, such as, without limitation, methyl, phenyl, pyridyl, etc. encompasses undeuterated, partially deuterated, and fully deuterated versions thereof. Similarly, classes of substituents such as, without limitation, alkyl, aryl, cycloalkyl, heteroaryl, etc. also encompass undeuterated, partially deuterated, and fully deuterated versions thereof.


In addition to and/or in combination with the materials disclosed herein, many hole injection materials, hole transporting materials, host materials, dopant materials, exiton/hole blocking layer materials, electron transporting and electron injecting materials may be used in an OLED. Non-limiting examples of the materials that may be used in an OLED in combination with materials disclosed herein are listed in TABLE 1 below. TABLE 1 lists non-limiting classes of materials, non-limiting examples of compounds for each class, and references that disclose the materials.











TABLE 1





MATERIAL
EXAMPLES OF MATERIAL
PUBLICATIONS















Hole injection materials









Phthalocyanine and porphyrin compounds


embedded image


Appl. Phys. Lett. 69, 2160 (1996)





Starburst triarylamines


embedded image


J. Lumin. 72-74, 985 (1997)





CFx Fluorohydrocarbon polymer


embedded image


Appl. Phys. Lett. 78, 673 (2001)





Conducting polymers (e.g., PEDOT:PSS, polyaniline, polythiophene)


embedded image


Synth. Met. 87, 171 (1997) WO2007002683





Phosphonic acid and silane SAMs


embedded image


US20030162053





Triarylamine or polythiophene polymers with conductivity dopants


embedded image


EP1725079A1








embedded image











embedded image








Organic compounds with conductive inorganic compounds, such as molybdenum and tungsten oxides


embedded image


US20050123751 SID Symposium Digest, 37, 923 (2006) WO2009018009





n-type semiconducting organic complexes


embedded image


US20020158242





Metal organometallic complexes


embedded image


US20060240279





Cross-linkable compounds


embedded image


US20080220265





Polythiophene based polymers and copolymers


embedded image


WO 2011075644 EP2350216










Hole transporting materials









Triarylamines (e.g., TPD, α-NPD)


embedded image


Appl. Phys. Lett. 51, 913 (1987)








embedded image


U.S. Pat. No. 5,061,569








embedded image


EP650955








embedded image


J. Mater. Chem. 3, 319 (1993)








embedded image


Appl. Phys. Lett. 90, 183503 (2007)








embedded image


Appl. Phys. Lett. 90, 183503 (2007)





Triarylamine on spirofluorene core


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Synth. Met. 91, 209 (1997)





Arylamine carbazole compounds


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Adv. Mater. 6, 677 (1994), US20080124572





Triarylamine with (di)benzothiophene/ (di)benzofuran


embedded image


US20070278938, US20080106190 US20110163302





Indolocarbazoles


embedded image


Synth. Met. 111, 421 (2000)





Isoindole compounds


embedded image


Chem. Mater. 15, 3148 (2003)





Metal carbene complexes


embedded image


US20080018221










Phosphorescent OLED host materials


Red hosts









Arylcarbazoles


embedded image


Appl. Phys. Lett. 78, 1622 (2001)





Metal 8-hydroxyquinolates (e.g., Alq3, BAlq)


embedded image


Nature 395, 151 (1998)








embedded image


US20060202194








embedded image


WO2005014551








embedded image


WO2006072002





Metal phenoxybenzothiazole compounds


embedded image


Appl. Phys. Lett. 90, 123509 (2007)





Conjugated oligomers and polymers (e.g., polyfluorene)


embedded image


Org. Electron. 1, 15 (2000)





Aromatic fused rings


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WO2009066779, WO2009066778, WO2009063833, US20090045731, US20090045730, WO2009008311, US20090008605, US20090009065





Zinc complexes


embedded image


WO2010056066





Chrysene based compounds


embedded image


WO2011086863










Green hosts









Arylcarbazoles


embedded image


Appl. Phys. Lett. 78, 1622 (2001)








embedded image


US20030175553








embedded image


WO2001039234





Aryltriphenylene compounds


embedded image


US20060280965








embedded image


US20060280965








embedded image


WO2009021126





Poly-fused heteroaryl compounds


embedded image


US20090309488 US20090302743 US20100012931





Donor acceptor type molecules


embedded image


WO2008056746








embedded image


WO2010107244





Aza-carbazole/DBT/DBF


embedded image


JP2008074939








embedded image


US20100187984





Polymers (e.g., PVK)


embedded image


Appl. Phys. Lett. 77, 2280 (2000)





Spirofluorene compounds


embedded image


WO2004093207





Metal phenoxybenzooxazole compounds


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WO2005089025








embedded image


WO2006132173








embedded image


JP200511610





Spirofluorene-carbazole compounds


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JP2007254297








embedded image


JP2007254297





Indolocarbazoles


embedded image


WO2007063796








embedded image


WO2007063754





5-member ring electron deficient heterocycles (e.g., triazole, oxadiazole)


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J. Appl. Phys. 90, 5048 (2001)








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WO2004107822





Tetraphenylene complexes


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US20050112407





Metal phenoxypyridine compounds


embedded image


WO2005030900





Metal coordination complexes (e.g., Zn, Al with N{circumflex over ( )}N ligands)


embedded image


US20040137268, US20040137267










Blue hosts









Arylcarbazoles


embedded image


Appl. Phys. Lett, 82, 2422 (2003)








embedded image


US20070190359





Dibenzothiophene/ Dibenzofuran-carbazole compounds


embedded image


WO2006114966, US20090167162








embedded image


US20090167162








embedded image


WO2009086028








embedded image


US20090030202, US20090017330








embedded image


US20100084966





Silicon aryl compounds


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US20050238919








embedded image


WO2009003898





Silicon/Germanium aryl compounds


embedded image


EP2034538A





Aryl benzoyl ester


embedded image


WO2006100298





Carbazole linked by non- conjugated groups


embedded image


US20040115476





Aza-carbazoles


embedded image


US20060121308





High triplet metal organometallic complex


embedded image


U.S. Pat. No. 7,154,114










Phosphorescent dopants


Red dopants









Heavy metal porphyrins (e.g., PtOEP)


embedded image


Nature 395, 151 (1998)





Iridium(III) organometallic complexes


embedded image


Appl. Phys. Lett. 78, 1622 (2001)








embedded image


US2006835469








embedded image


US2006835469








embedded image


US20060202194








embedded image


US20060202194








embedded image


US20070087321








embedded image


US20080261076 US20100090591








embedded image


US20070087321








embedded image


Adv. Mater. 19, 739 (2007)








embedded image


WO2009100991








embedded image


WO2008101842








embedded image


U.S. Pat. No. 7,232,618





Platinum(II) organometallic complexes


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WO2003040257








embedded image


US20070103060





Osmium(III) complexes


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Chem. Mater. 17, 3532 (2005)





Ruthenium(II) complexes


embedded image


Adv. Mater. 17, 1059 (2005)





Rhenium (I), (II), and (III) complexes


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US20050244673










Green dopants









Iridium(III) organometallic complexes


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  and its derivatives

Inorg. Chem. 40, 1704 (2001)








embedded image


US20020034656








embedded image


U.S. Pat. No. 7,332,232








embedded image


US20090108737








embedded image


WO2010028151








embedded image


EP1841834B








embedded image


US20060127696








embedded image


US20090039776








embedded image


U.S. Pat. No. 6,921,915








embedded image


US20100244004








embedded image


U.S. Pat. No. 6,687,266








embedded image


Chem. Mater. 16, 2480 (2004)








embedded image


US20070190359








embedded image


US 20060008670 JP2007123392








embedded image


WO2010086089, WO2011044988








embedded image


Adv. Mater. 16, 2003 (2004)








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Angew. Chem. Int. Ed. 2006, 45, 7800








embedded image


WO2009050290








embedded image


US20090165846








embedded image


US20080015355








embedded image


US20010015432








embedded image


US20100295032





Monomer for polymeric metal organometallic compounds


embedded image


U.S. Pat. No. 7,250,226, U.S. Pat. No. 7,396,598





Pt(II) organometallic complexes, including polydentated ligands


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Appl. Phys. Lett. 86, 153505 (2005)








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Appl. Phys. Lett. 86, 153505 (2005)








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Chem. Lett. 34, 592 (2005)








embedded image


WO2002015645








embedded image


US20060263635








embedded image


US20060182992 US20070103060





Cu complexes


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WO2009000673








embedded image


US20070111026





Gold complexes


embedded image


Chem. Commun. 2906 (2005)





Rhenium(III) complexes


embedded image


Inorg. Chem. 42, 1248 (2003)





Osmium(II) complexes


embedded image


U.S. Pat. No. 7,279,704





Deuterated organometallic complexes


embedded image


US20030138657





Organometallic complexes with two or more metal centers


embedded image


US20030152802








embedded image


U.S. Pat. No. 7,090,928










Blue dopants









Iridium(III) organometallic complexes


embedded image


WO2002002714








embedded image


WO2006009024








embedded image


US20060251923 US20110057559 US20110204333








embedded image


U.S. Pat. No. 7,393,599, WO2006056418, US20050260441, WO2005019373








embedded image


U.S. Pat. No. 7,534,505








embedded image


WO2011051404








embedded image


U.S. Pat. No. 7,445,855








embedded image


US20070190359, US20080297033 US20100148663








embedded image


U.S. Pat. No. 7,338,722








embedded image


US20020134984








embedded image


Angew. Chem. Int. Ed. 47, 4542 (2008)








embedded image


Chem. Mater. 18, 5119 (2006)








embedded image


Inorg. Chem. 46, 4308 (2007)








embedded image


WO2005123873








embedded image


WO2005123873








embedded image


WO2007004380








embedded image


WO2006082742





Osmium(II) complexes


embedded image


U.S. Pat. No. 7,279,704








embedded image


Organometallics 23, 3745 (2004)





Gold complexes


embedded image


Appl. Phys. Lett. 74, 1361 (1999)





Platinum(II) complexes


embedded image


WO2006098120, WO2006103874





Pt tetradentate complexes with at least one metal- carbene bond


embedded image


U.S. Pat. No. 7,655,323










Exciton/hole blocking layer materials









Bathocuprine compounds (e.g., BCP, BPhen)


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Appl. Phys. Lett. 75, 4 (1999)








embedded image


Appl. Phys. Lett. 79, 449 (2001)





Metal 8-hydroxyquinolates (e.g., BAlq)


embedded image


Appl. Phys. Lett. 81, 162 (2002)





5-member ring electron deficient heterocycles such as triazole, oxadiazole, imidazole, benzoimidazole


embedded image


Appl. Phys. Lett. 81, 162 (2002)





Triphenylene compounds


embedded image


US20050025993





Fluorinated aromatic compounds


embedded image


Appl. Phys. Lett. 79, 156 (2001)





Phenothiazine-S-oxide


embedded image


WO2008132085





Silylated five-membered nitrogen, oxygen, sulfur or phosphorus dibenzoheterocycles


embedded image


WO2010079051





Aza-carbazoles


embedded image


US20060121308










Electron transporting materials









Anthracene- benzoimidazole compounds


embedded image


WO2003060956








embedded image


US20090179554





Aza triphenylene derivatives


embedded image


US20090115316





Anthracene-benzothiazole compounds


embedded image


Appl. Phys. Lett. 89, 063504 (2006)





Metal 8-hydroxyquinolates (e.g., Alq3, Zrq4)


embedded image


Appl. Phys. Lett. 51, 913 (1987) U.S. Pat. No. 7,230,107





Metal hydroxybenzoquinolates


embedded image


Chem. Lett. 5, 905 (1993)





Bathocuprine compounds such as BCP, BPhen, etc


embedded image


Appl. Phys. Lett. 91, 263503 (2007)








embedded image


Appl. Phys. Lett. 79, 449 (2001)





5-member ring electron deficient heterocycles (e.g., triazole, oxadiazole, imidazole, benzoimidazole)


embedded image


Appl. Phys. Lett. 74, 865 (1999)








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Appl. Phys. Lett. 55, 1489 (1989)








embedded image


Jpn. J. Apply. Phys. 32, L917 (1993)





Silole compounds


embedded image


Org. Electron. 4, 113 (2003)





Arylborane compounds


embedded image


J. Am. Chem. Soc. 120, 9714 (1998)





Fluorinated aromatic compounds


embedded image


J. Am. Chem. Soc. 122, 1832 (2000)





Fullerene (e.g., C60)


embedded image


US20090101870





Triazine complexes


embedded image


US20040036077





Zn (N{circumflex over ( )}N) complexes


embedded image


U.S. Pat. No. 6,528,187









EXPERIMENTAL

Chemical abbreviations used throughout this document are as follows: S-Phos is dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine, Pd2(dba)3 is tri(dibenzylideneacetone) dipalladium(0), THF is tetrahydrofuran, and DCM is dichloromethane.


Example 1
Synthesis of Compound 43-S



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Into a solution of 9-(dibenzo[b,d]thiophen-2-yl)-9H-carbazole (4.8 g, 13.8 mmol) in THF (100 mL) was slowly added a n-butyllithium solution in hexane (2.5 M, 7.14 mL, 17.9 mmol) at −78° C. The solution was gradually warmed to 5° C. and stirred for 6 hours at between 0 to 10° C. The solution was cooled to −78° C. and 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (4.3 mL, 20.6 mmol) was added at once. The solution was slowly warmed to room temperature and stirred overnight before quenching with water. The reaction mixture was extracted with ether, washed with brine and water, dried over MgSO4, and the solvent was evaporated. The residue was purified by column chromatography on silica gel with heptane/DCM as eluent and trituration with heptane to yield 9-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dibenzo[b,d]thiophen-2-yl)-9H-carbazole (3.8 g, 57%) as a white powder.




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A solution of 9-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dibenzo[b,d]thiophen-2-yl)-9H-carbazole (3.0 g, 6.3 mmol), 2-(3-bromophenyl)triphenylene (2.4 g, 6.31 mmol), Pd2(dba)3 (0.116 g, 0.126 mmol), S-Phos (0.104 g, 0.252 mmol), and K3PO4 (4.02 g, 18.93 mmol) in toluene (100 mL) and water (15 mL) was refluxed under nitrogen at 110° C. for 3 hour. After cooling to room temperature, the solution was diluted with water and the solid was collected by filtration. The crude product was redissolved in boiling toluene (800 mL) and filtered through a short plug of silica gel topped with a layer of anhydrous MgSO4. The filtrate was concentrated and the white solid was collected and triturated with boiling xylene and dichloromethane successively to yield Compound 43-S (3.5 g, 85%) as a white solid.


Example 2
Synthesis of Compound 17-S



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A mixture of 4,4,5,5-tetramethyl-2-(6-(triphenylen-2-yl)dibenzo[b,d]thiophen-4-yl)-1,3,2-dioxaborolane (2.7 g, 5.03 mmol), 9-(3′-bromo-[1,1′-biphenyl]-3-yl)-9H-carbazole (2.065 g, 5.18 mmol), tris(dibenzylideneacetone)palladium(0) (0.138 g, 0.151 mmol), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.310 g, 0.755 mmol) was charged into 250 mL of toluene. Potassium phosphate tribasic monohydrate (3.47 g, 15.10 mmol) was dissolved in 25 mL of water and the solution was charged into the reaction mixture. The reaction mixture was degassed with nitrogen then was heated at reflux overnight. The reaction mixture was cooled to room temperature. The toluene layer was separated and dried under vacuum. The crude residue was passed through a silica gel column using 35-99% toluene/hexanes. The cleanest product fractions were combined and concentrated under vacuum. The cleanest fractions were recrystallized from toluene. 9-(3′-(6-(triphenylen-2-yl)dibenzo[b,d]thiophen-4-yl)-[1,1′-biphenyl]-3-yl)-9H-carbazole (Compound 17-S) (1.832 g, 2.52 mmol, 50% yield) was isolated as a white solid.


Example 3
Synthesis of Compound 7-S



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4-bromo-6-(triphenylen-2-yl)dibenzo[b,d]thiophene (5 g, 10.22 mmol), 9H-carbazole (1.999 g, 11.95 mmol), sodium tert-butoxide (1.964 g, 20.43 mmol), tris(dibenzylideneacetone)palladium(0) (0.280 g, 0.306 mmol), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.628 g, 1.532 mmol) were charged into a 3-neck flask with 300 mL of m-xylenes. The reaction mixture was degassed using nitrogen. The reaction was then heated to reflux for 24 hours. The reaction mixture was cooled to room temperature and was diluted with 100 mL of water. The mixture was passed through a pad of celite. The organic layer was separated and was dried over magnesium sulfate. The mixture was filtered and concentrated under vacuum. The crude residue was passed through a silica gel column using 35-50% toluene/hexanes. The cleanest fractions were combined and concentrated under vacuum. The cleanest fractions were triturated with hot ethanol to remove excess carbazole. The solid was then triturated with hot heptanes/toluene. A white solid was collected via filtration and was recrystallized from toluene. 9-(6-(triphenylen-2-yl)dibenzo[b,d]thiophen-4-yl)-9H-carbazole (Compound 7-S) (3.04 g, 5.28 mmol, 51.7% yield) was isolated as a white solid.


Example 4
Synthesis of Compound 11-S



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9H-3,9′-bicarbazole (1.88 g, 5.66 mmol), sodium tert-butoxide (1 g, 10.42 mmol), tris(dibenzylideneacetone)palladium(0) (0.22 g, 0.240 mmol), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.5 g, 1.220 mmol) were charged into a reaction flask with 210 mL of o-xylenes. The mixture was degassed with nitrogen then was heated to reflux for 2½ days. The reaction mixture was cooled to room temperature. A solid was collected via filtration. The solid was dissolved in 1 L of hot toluene then was passed through a silica gel column. The column was flushed with hot toluene. The toluene filtrate was concentrated under vacuum. The crude solid was triturated with 300 mL of hot ethanol then was filtered under vacuum. The solid collected was then recrystallized twice from hot toluene to yield 9-(6-(triphenylen-2-yl)dibenzo[b,d]thiophen-4-yl)-9H-3,9′-bicarbazole (Compound 11-S) (2.25 g, 3.04 mmol, 59.5% yield) as a white solid.


Example 5
Synthesis of Compound 4-O



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4,4,5,5-tetramethyl-2-(6-(triphenylen-2-yl)dibenzo[b,d]furan-4-yl)-1,3,2-dioxaborolane (3 g, 5.76 mmol), 9-(3-bromophenyl)-9H-carbazole (2 g, 6.21 mmol), tris(dibenzylideneacetone)palladium(0) (0.109 g, 0.119 mmol), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.195 g, 0.476 mmol) were charged into a reaction flask with 150 mL of toluene. Potassium phosphate tribasic (4.42 g, 20.85 mmol) was dissolved in 15 mL of water then charged into the reaction mixture. The reaction mixture was degassed using nitrogen then was heated at reflux overnight. The reaction mixture was cooled to room temperature. A solid was collected via filtration. This solid was triturated with 300 mL of warm methanol. The solid was filtered and dried under vacuum. This solid was then dissolved in 800 mL of refluxing toluene then was passed through a pad of silica gel. The filtrate was concentrated under vacuum then was recrystallized twice from toluene. 9-(3-(6-(triphenylen-2-yl)dibenzo[b,d]furan-4-yl)phenyl)-9H-carbazole (Compound4-O) (1.75 g, 2.75 mmol, 47.8% yield) was isolated as a white solid.


Example 6
Synthesis of Compound 4-S



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4,4,5,5-tetramethyl-2-(6-(triphenylen-2-yl)dibenzo[b,d]thiophene-4-yl)-1,3,2-dioxaborolane (2.88 g, 5.37 mmol), 9-(3-bromophenyl)-9H-carbazole (1.78 g, 5.53 mmol), tris(dibenzylideneacetone)palladium(0) (0.098 g, 0.107 mmol), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.176 g, 0.429 mmol) were charged into a reaction flask with 150 mL of toluene. Potassium phosphate tribasic (3.99 g, 18.79 mmol) was dissolved in 15 mL of water then was charged into the reaction mixture. The reaction mixture was degassed using nitrogen then was heated at reflux overnight. The reaction mixture was cooled to room temperature. A solid was collected via filtration and washed with methanol and ethyl acetate. This solid was then dissolved in ˜500 mL of refluxing toluene then was passed through a pad of silica gel. The filtrate was concentrated under vacuum then was recrystallized from toluene. 9-(3-(6-(triphenylen-2-yl)dibenzo[b,d]thiophene-4-yl)phenyl)-9H-carbazole (Compound 4-S) (2.6 g, 74.3% yield) was isolated as a white solid.


Example 7
Synthesis of Compound 1-S



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4,4,5,5-tetramethyl-2-(6-(triphenylen-2-yl)dibenzo[b,d]thiophene-4-yl)-1,3,2-dioxaborolane (2.94 g, 5.49 mmol), 9-(4-bromophenyl)-9H-carbazole (1.75 g, 5.43 mmol), tris(dibenzylideneacetone)palladium(0) (0.099 g, 0.109 mmol), and 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.178 g, 0.435 mmol) were charged into a reaction flask with 120 mL of toluene. Potassium phosphate tribasic (4.04 g, 19.01 mmol) was dissolved in 10 mL of water then was charged into the reaction mixture. The reaction mixture was degassed using nitrogen for 30 minutes then was heated at reflux overnight. The reaction mixture was cooled to room temperature. A solid was collected via filtration. This solid was triturated with 300 mL of warm methanol and washed with ethyl acetate. The solid was filtered and dried under vacuum. This solid was then dissolved in 1200 mL of refluxing toluene then was passed through a pad of silica gel. The filtrate was concentrated under vacuum then was recrystallized from toluene. Compound 1-S (1.1 g, 31.1% yield) was isolated as a white solid.


Example 8
Synthesis of Compound 20-S



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A solution of tris(dibenzylideneacetone) dipalladium(0) (0.142 g, 0.155 mmol), 4-bromo-6-(triphenylen-2-yl)dibenzo[b,d]thiophene (3.8 g, 7.76 mmol), 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (3.01 g, 8.15 mmol), S-phos (0.255 g, 0.621 mmol), and K3PO4 (5.77 g, 27.2 mmol) in toluene (200 mL) and water (20 mL) was heated at reflux under N2 for 48 hours. The reaction mixture was cooled to room temperature and diluted with dichloromethane. After washing with water, the organic layer was concentrated. The residual solid was triturated with methanol and then triturated with ethyl acetate. The solid was dissolved in refluxing toluene and filtered while hot through a silica gel plug topped with a layer of magnesium sulfate. The filtrate was concentrated leaving a white solid which was recrystallized from toluene yielding Compound 20-S (2.6 g, 43% yield) of a white solid.


Comparative Device Examples

All comparative device examples were fabricated by high vacuum (<10−7 Torr) thermal evaporation. The anode electrode is 1,200 Å of indium tin oxide (ITO). The cathode consisted of 10 Å of LiF followed by 1,000 Å of Aluminum. All devices are encapsulated with a glass lid sealed with an epoxy resin in a nitrogen glove box (<1 ppm of H2O and O2) immediately after fabrication, and a moisture getter was incorporated inside the package.


The organic stack of the device examples consisted of sequentially, from the ITO surface, 100 Å of Compound H as the hole injection layer (HIL), 400 Å of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPD) as the hole transporting layer (HTL), 300 Å of 15% of Compound B1 as dopant in Compound H1 and Compound H2 as the emissive layer (EML), 400 Å of Alq (tris-8-hydroxyquinoline aluminum) as the electron transport layer (ETL).


As used herein, Compound H, NPD, Alq, Compound B1, Compound H1, and Compound H2 have the following structures:




embedded image


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TABLE 2 summarizes the performance of the devices. The lifetime (LT80%) was defined as the time required for the device to decay to 80% of its initial luminance (L0) of 2000 nits. Devices comprising Compounds H1 and H2 showed the same device lifetime, which indicates that the carbazole substitution position on dibenzothiophene does not affect device performance. Therefore, comparative devices examples using Compound C below as the host should give valid device results comparison.









TABLE 2







Device structures and results










Example
EML (300 Å, doping %)
CIE (x, y)
LT80% (h)














Example 1
Compound
Compound B1
(0.174, 0.370)
167



H1
15%


Example 2
Compound
Compound B1
(0.176, 0.375)
170



H2
15%









Device Examples

Device examples were fabricated by high vacuum (<10−7 Torr) thermal evaporation. The anode electrode was 1,200 Å of indium tin oxide (ITO). The cathode consisted of 10 Å of LiF followed by 1,000 Å of Aluminum. All devices are encapsulated with a glass lid sealed with an epoxy resin in a nitrogen glove box (<1 ppm of H2O and O2) immediately after fabrication, and a moisture getter was incorporated inside the package.


The organic stack of the device examples consisted of sequentially, from the ITO surface, 100 Å of Compound A as the hole injection layer (HIL), 300 Å of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPD) as the hole transporting layer (HTL), 300 Å of the invention compounds doped with Compound A as dopant with 10 weight percent of the iridium phosphorescent compound as the emissive layer (EML), 50 Å of compound BL as a blocking layer (BL), 450 Å of Alq (tris-8-hydroxyquinoline aluminum) as the electron transport layer (ETL). The comparative example with Compound C was fabricated similarly to the Device Examples except that in the Device Examples 1, 2, and 3, Compounds 4-S, 7-S, and 11-S, respectively, were used as the host in the EML.


The device structures are provided in TABLE 3. As used herein, Compound A, Compound C, NPD, Compound BL, and Alq have the following structures:




embedded image









TABLE 3







Device Structures












Example
HIL
HTL
EML (300 Å, doping %)
BL
ETL
















Comparative
Compound A
NPD 300 Å
Compound C
Compound A
Compound
Alq 400 Å


Example 1
100 Å


10%
BL 50 Å



Inventive
Compound A
NPD 300 Å
Compound 7-S
Compound A
Compound
Alq 450 Å


Example 1
100 Å


10%
BL 50 Å



Inventive
Compound A
NPD 300 Å
Compound 4-S
Compound A
Compound
Alq 450 Å


Example 2
100 Å


10%
BL 50 Å



Inventive
Compound A
NPD 300 Å
Compound 11-S
Compound A
Compound
Alq 450 Å


Example 3
100 Å


10%
BL 50 Å
















TABLE 4







VTE Device Results










1931 CIE












x
y
LT80% @ 40 mA/cm2














Comparative Example 1
0.37
0.60
100


Inventive Example 1
0.37
0.60
397


Inventive Example 2
0.37
0.60
343


Inventive Example 3
0.36
0.60
147









TABLE 4 provides color coordinate and lifetime of the devices. The colors were recorded as green for all examples. The device lifetime LT80, which is defined by 20% degradation from the initial luminance, was measured under a constant current density of 40 mA/cm2. The LT80 data in TABLE 4 was normalized by the lifetime of Comparative Example 1. As shown in TABLE 4, the LT80 of device examples using inventive Compounds 7-S, 4-S, and 11-S, respectively, in the EML layer, are 297%, 243%, and 47% longer than the device example using comparative Compound C in the EML layer of the device.


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 may be substituted with other materials and structures without deviating from the spirit of the invention. The present invention as claimed may therefore include variations from the particular examples and preferred embodiments described herein, as will be apparent to one of skill in the art. It is understood that various theories as to why the invention works are not intended to be limiting.

Claims
  • 1. A compound having formula I:
  • 2. The compound of claim 1, wherein the compound has formula IV:
  • 3. The compound of claim 1, wherein the compound has formula V:
  • 4. The compound of claim 1, wherein G is connected to L2 at the nitrogen atom of the 9-position of carbazole.
  • 5. The compound of claim 1, wherein G is connected to L2 at a carbon atom at the 1-, 2-, 3-, or 4-position of carbazole.
  • 6. The compound of claim 1, wherein one of R4b, R5a, or R5c is L2-G.
  • 7. The compound of claim 1, wherein L2 is selected from the group consisting of a direct bond, a phenyl group, and a biphenyl group.
  • 8. The compound of claim 1, wherein R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, wherein R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof, and wherein R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, aryl, heteroaryl, and combinations thereof.
  • 9. The compound of claim 1, wherein R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, wherein R3a, R3b, R3c, and R3d that are not formula II are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof, and wherein R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are each independently selected from the group consisting of hydrogen, deuterium, phenyl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, pyridine, phenyl pyridine, pyridyl phenyl, triphenylene, carbazole, fluorene, dibenzofuran, dibenzothiophene, dibenzoselenophene, and combinations thereof.
  • 10. The compound of claim 1, wherein R1a, R1b, R1c, R1d, R2a, R2b, R2c, and R2d are hydrogen, wherein R3a, R3b, R3c, and R3d that are not formula II are hydrogen, and wherein R4a, R4b, R4c, R5a, R5b, R5c, and R5d that are not formula III are hydrogen.
  • 11. The compound of claim 1, wherein X is O.
  • 12. The compound of claim 1, wherein X is S.
  • 13. The compound of claim 1, wherein X is S, L2 is a direct bond, and R5ais L2-G.
  • 14. The compound of claim 1, wherein X is S, L2 is phenyl, and R5ais L2-G.
  • 15. The compound of claim 1, wherein the compound is selected from the group consisting of:
  • 16. A first device comprising an organic light emitting device, the organic light emitting device comprising: an anode;a cathode;an organic layer, disposed between the anode and the cathode, wherein the organic layer comprises a compound having formula I:
  • 17. The first device of claim 16, further comprising a blocking layer and the compound of formula I is a blocking material in the organic layer.
  • 18. A formulation comprising a compound having formula I:
Parent Case Info

This application claims priority to U.S. Provisional Application No. 61/846,100, filed Jul. 15, 2013, which is incorporated by reference in its entirety.

US Referenced Citations (82)
Number Name Date Kind
4769292 Tang et al. Sep 1988 A
5061569 VanSlyke et al. Oct 1991 A
5247190 Friend et al. Sep 1993 A
5703436 Forrest et al. Dec 1997 A
5707745 Forrest et al. Jan 1998 A
5834893 Bulovic et al. Nov 1998 A
5844363 Gu et al. Dec 1998 A
6013982 Thompson et al. Jan 2000 A
6087196 Sturm et al. Jul 2000 A
6091195 Forrest et al. Jul 2000 A
6097147 Baldo et al. Aug 2000 A
6294398 Kim et al. Sep 2001 B1
6303238 Thompson et al. Oct 2001 B1
6337102 Forrest et al. Jan 2002 B1
6468819 Kim et al. Oct 2002 B1
6528187 Okada Mar 2003 B1
6687266 Ma et al. Feb 2004 B1
6835469 Kwong et al. Dec 2004 B2
6921915 Takiguchi et al. Jul 2005 B2
7087321 Kwong et al. Aug 2006 B2
7090928 Thompson et al. Aug 2006 B2
7154114 Brooks et al. Dec 2006 B2
7250226 Tokito et al. Jul 2007 B2
7279704 Walters et al. Oct 2007 B2
7332232 Ma et al. Feb 2008 B2
7338722 Thompson et al. Mar 2008 B2
7393599 Thompson et al. Jul 2008 B2
7396598 Takeuchi et al. Jul 2008 B2
7431968 Shtein et al. Oct 2008 B1
7445855 Mackenzie et al. Nov 2008 B2
7534505 Lin et al. May 2009 B2
20020034656 Thompson et al. Mar 2002 A1
20020134984 Igarashi Sep 2002 A1
20020158242 Son et al. Oct 2002 A1
20030138657 Li et al. Jul 2003 A1
20030152802 Tsuboyama et al. Aug 2003 A1
20030162053 Marks et al. Aug 2003 A1
20030175553 Thompson et al. Sep 2003 A1
20030230980 Forrest et al. Dec 2003 A1
20040036077 Ise Feb 2004 A1
20040137267 Igarashi et al. Jul 2004 A1
20040137268 Igarashi et al. Jul 2004 A1
20040174116 Lu et al. Sep 2004 A1
20050025993 Thompson et al. Feb 2005 A1
20050112407 Ogasawara et al. May 2005 A1
20050238919 Ogasawara Oct 2005 A1
20050244673 Satoh et al. Nov 2005 A1
20050260441 Thompson et al. Nov 2005 A1
20050260449 Walters et al. Nov 2005 A1
20060008670 Lin et al. Jan 2006 A1
20060202194 Jeong et al. Sep 2006 A1
20060240279 Adamovich et al. Oct 2006 A1
20060251923 Lin et al. Nov 2006 A1
20060263635 Ise Nov 2006 A1
20060280965 Kwong et al. Dec 2006 A1
20070190359 Knowles et al. Aug 2007 A1
20070278938 Yabunouchi et al. Dec 2007 A1
20080015355 Schafer et al. Jan 2008 A1
20080018221 Egen et al. Jan 2008 A1
20080106190 Yabunouchi et al. May 2008 A1
20080124572 Mizuki et al. May 2008 A1
20080220265 Xia et al. Sep 2008 A1
20080297033 Knowles et al. Dec 2008 A1
20090008605 Kawamura et al. Jan 2009 A1
20090009065 Nishimura et al. Jan 2009 A1
20090017330 Iwakuma et al. Jan 2009 A1
20090030202 Iwakuma et al. Jan 2009 A1
20090039776 Yamada et al. Feb 2009 A1
20090045730 Nishimura et al. Feb 2009 A1
20090045731 Nishimura et al. Feb 2009 A1
20090101870 Pakash et al. Apr 2009 A1
20090108737 Kwong et al. Apr 2009 A1
20090115316 Zheng et al. May 2009 A1
20090165846 Johannes et al. Jul 2009 A1
20090167162 Lin et al. Jul 2009 A1
20090179554 Kuma et al. Jul 2009 A1
20100237334 Ma et al. Sep 2010 A1
20130049576 Katakura Feb 2013 A1
20130060037 Lin et al. Mar 2013 A1
20130087776 Lee et al. Apr 2013 A1
20130112952 Adamovich May 2013 A1
20130207092 Huh et al. Aug 2013 A1
Foreign Referenced Citations (48)
Number Date Country
0650955 May 1995 EP
1725079 Nov 2006 EP
2034538 Mar 2009 EP
200511610 Jan 2005 JP
2007123392 May 2007 JP
2007254297 Oct 2007 JP
2008074939 Apr 2008 JP
0139234 May 2001 WO
0202714 Jan 2002 WO
0215654 Feb 2002 WO
0340257 May 2003 WO
03060956 Jul 2003 WO
2004093207 Oct 2004 WO
2004107822 Dec 2004 WO
2005014551 Feb 2005 WO
2005019373 Mar 2005 WO
2005030900 Apr 2005 WO
2005089025 Sep 2005 WO
2005123873 Dec 2005 WO
2006009024 Jan 2006 WO
2006056418 Jun 2006 WO
2006072002 Jul 2006 WO
2006082742 Aug 2006 WO
2006098120 Sep 2006 WO
2006100298 Sep 2006 WO
2006103874 Oct 2006 WO
2006114966 Nov 2006 WO
2006132173 Dec 2006 WO
2007002683 Jan 2007 WO
2007004380 Jan 2007 WO
2007063754 Jun 2007 WO
2007063796 Jun 2007 WO
2008056746 May 2008 WO
2008101842 Aug 2008 WO
2008132085 Nov 2008 WO
2009000673 Dec 2008 WO
2009003898 Jan 2009 WO
2009008311 Jan 2009 WO
2009018009 Feb 2009 WO
2009021126 Feb 2009 WO
2009050290 Apr 2009 WO
2009062578 May 2009 WO
2009063833 May 2009 WO
2009066778 May 2009 WO
2009066779 May 2009 WO
2009086028 Jul 2009 WO
2009100991 Aug 2009 WO
WO 2011136755 Mar 2011 WO
Non-Patent Literature Citations (47)
Entry
Extended European Search Report dated Nov. 6, 2014 for corresponding EP Application No. 14176384.7.
Adachi, Chihaya et al., “Organic Electroluminescent Device Having a Hole Conductor as an Emitting Layer,” Appl. Phys. Lett., 55(15): 1489-1491 (1989).
Adachi, Chihaya et al., “Nearly 100% Internal Phosphorescence Efficiency in an Organic Light Emitting Device,” J. Appl. Phys., 90(10): 5048-5051 (2001).
Adachi, Chihaya et al., “High-Efficiency Red Electrophosphorescence Devices,” Appl. Phys. Left., 78(11)1622-1624 (2001).
Aonuma, Masaki et al., “Material Design of Hole Transport Materials Capable of Thick-Film Formation in Organic Light Emitting Diodes,” Appl. Phys. Lett., 90, Apr. 30, 2007, 183503-1-183503-3.
Baldo et al., Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices, Nature, vol. 395, 151-154, (1998).
Baldo et al., Very high-efficiency green organic light-emitting devices based on electrophosphorescence, Appl. Phys. Lett., vol. 75, No. 1, 4-6 (1999).
Gao, Zhicliang et al., “Bright-Blue Electroluminescence From a Silyl-Substituted ter-(phenylene-vinylene) derivative,” Appl. Phys. Lett., 74(6): 865-867 (1999).
Guo, Tzung-Fang et al., “Highly Efficient Electrophosphorescent Polymer Light-Emitting Devices,” Organic Electronics, 1: 15-20 (2000).
Hamada, Yuji et al., “High Luminance in Organic Electroluminescent Devices with Bis(10-hydroxybenzo[h]quinolinato) beryllium as an Emitter,” Chem. Lett., 905-906 (1993).
Holmes, R.J. et al., “Blue Organic Electrophosphorescence Using Exothermic Host-Guest Energy Transfer,” Appl. Phys. Lett., 82(15):2422-2424 (2003).
Hu, Nan-Xing et al., “Novel High Tg Hole-Transport Molecules Based on Indolo[3,2-b]carbazoles for Organic Light-Emitting Devices,” Synthetic Metals, 111-112:421-424 (2000).
Huang, Jinsong et al., “Highly Efficient Red-Emission Polymer Phosphorescent Light-Emitting Diodes Based on Two Novel Tris(1-phenylisoquinolinato-C2,N)iridium(III) Derivatives,” Adv. Mater., 19:739-743 (2007).
Huang, Wei-Sheng et al., “Highly Phosphorescent Bis-Cyclometalated Iridium Complexes Containing Benzoimidazole-Based Ligands,” Chem. Mater., 16(12):2480-2488 (2004).
Hung, L.S. et al., “Anode Modification in Organic Light-Emitting Diodes by Low-Frequency Plasma Polymerization of CHF3,” Appl. Phys. Lett., 78(5):673-675 (2001).
Ikai, Masamichi et al., “Highly Efficient Phosphorescence From Organic Light-Emitting Devices with an Exciton-Block Layer,” Appl. Phys. Lett., 79(2):156-158 (2001).
Ikeda, Hisao et al., “P-185 Low-Drive-Voltage OLEDs with a Buffer Layer Having Molybdenum Oxide,” SID Symposium Digest, 37:923-926 (2006).
Inada, Hiroshi and Shirota, Yasuhiko, “1,3,5-Tris[4-(diphenylamino)phenyl]benzene and its Methylsubstituted Derivatives as a Novel Class of Amorphous Molecular Materials,” J. Mater. Chem., 3(3):319-320 (1993).
Kanno, Hiroshi et al., “Highly Efficient and Stable Red Phosphorescent Organic Light-Emitting Device Using bis[2-(2- benzothiazoyl)phenolato]zinc(II) as host material,” Appl. Phys. Lett., 90:123509-1-123509-3 (2007).
Kido, Junji et al., 1,2,4-Triazole Derivative as an Electron Transport Layer in Organic Electroluminescent Devices, Jpn. J. Appl. Phys., 32:L917-L920 (1993).
Kuwabara, Yoshiyuki et al., “Thermally Stable Multilayered Organic Electroluminescent Devices Using Novel Starburst Molecules, 4,4′,4″-Tri(N-carbazolyl)triphenylamine (TCTA) and 4,4″,4″-Tris(3-methylphenylphenyl-amino) triphenylamine (m-MTDATA), as Hole-Transport Materials,” Adv. Mater., 6(9) 677-679 (1994).
Kwong, Raymond C. et al., “High Operational Stability of Electrophosphorescent Devices,” Appl. Phys. Left., 81(1)162-164 (2002).
Lamansky, Sergey et al., “Synthesis and Characterization of Phosphorescent Cyclometalated Iridium Complexes,” Inorg. Chem., 40(7):1704-1711 (2001).
Lee, Chang-Lyoul et al., “Polymer Phosphorescent Light-Emitting Devices Doped with Tris(2-phenylpyridine) Iridium as a Triplet Emitter,” Appl. Phys. Lett., 77(15):2280-2282 (2000).
Lo, Shih-Chun et al., “Blue Phosphorescence from Iridium(III) Complexes at Room Temperature,” Chem. Mater., 18 (21)5119-5129 (2006).
Ma, Yuguang et al., “Triplet Luminescent Dinuclear-Gold(I) Complex-Based Light-Emitting Diodes with Low Turn-On voltage,” Appl. Phys. Lett., 74(10)1361-1363 (1999).
Mi, Bao-Xiu et al., “Thermally Stable Hole-Transporting Material for Organic Light-Emitting Diode an Isoindole Derivative,” Chem. Mater., 15(16):3148-3151 (2003).
Nishida, Jun-ichi et al., “Preparation, Characterization, and Electroluminescence Characteristics of α-Diimine-type Platinum(II) Complexes with Perfluorinated Phenyl Groups as Ligands,” Chem. Lett., 34(4): 592-593 (2005).
Niu, Yu-Hua et al., “Highly Efficient Electrophosphorescent Devices with Saturated Red Emission from a Neutral Osmium Complex,” Chem. Mater., 17(13):3532-3536 (2005).
Noda, Tetsuya and Shirota,Yasuhiko, “5,5′-Bis(dimesitylbory1)-2,2′-bithiophene and 5,5″-Bis (dimesitylboryl)-2,2′5′,2″-terthiophene as a Novel Family of Electron-Transporting Amorphous Molecular Materials,” J. Am. Chem. Soc., 120 (37):9714-9715 (1998).
Okumoto, Kenji et al., “Green Fluorescent Organic Light-Emitting Device with External Quantum Efficiency of Nearly 10%,” Appl. Phys. Lett., 89:063504-1-063504-3 (2006).
Palilis, Leonidas C., “High Efficiency Molecular Organic Light-Emitting Diodes Based on Silole Derivatives and Their Exciplexes,” Organic Electronics, 4:113-121 (2003).
Paulose, Betty Marie Jennifer S. et al., “First Examples of Alkenyl Pyridines as Organic Ligands for Phosphorescent Iridium Complexes,” Adv. Mater., 16(22):2003-2007 (2004).
Ranjan, Sudhir et al., “Realizing Green Phosphorescent Light-Emitting Materials from Rhenium(I) Pyrazolato Diimine Complexes,” Inorg. Chem., 42(4):1248-1255 (2003).
Sakamoto, Youichi et al., “Synthesis, Characterization, and Electron-Transport Property of Perfluorinated Phenylene Dendrimers,” J. Am. Chem. Soc., 122(8):1832-1833 (2000).
Salbeck, J. et al., “Low Molecular Organic Glasses for Blue Electroluminescence,” Synthetic Metals, 91: 209-215 (1997).
Shirota, Yasuhiko et al., “Starburst Molecules Based on pi-Electron Systems as Materials for Organic Electroluminescent Devices,” Journal of Luminescence, 72-74:985-991 (1997).
Sotoyama, Wataru et al., “Efficient Organic Light-Emitting Diodes with Phosphorescent Platinum Complexes containing Nacan-Coordinating Tridentate Ligand,” Appl. Phys. Lett., 86:153505-1-153505-3 (2005).
Sun, Yiru and Forrest, Stephen R., “High-Efficiency White Organic Light Emitting Devices with Three Separate Phosphorescent Emission Layers,” Appl. Phys. Lett., 91:263503-1-263503-3 (2007).
T. Österg{dot over (a)}rd et al., “Langmuir-Blodgett Light-Emitting Diodes of Poly(3-Hexylthiophene) Electro-Optical Characteristics Related to Structure,” Synthetic Metals, 88:171-177 (1997).
Takizawa, Shin-ya et al., “Phosphorescent Iridium Complexes Based on 2-Phenylimidazo[1,2- α]pyridine Ligands Tuning of Emission Color toward the Blue Region and Application to Polymer Light-Emitting Devices,” Inorg. Chem., 46(10):4308-4319 (2007).
Tang, C.W. And VanSlyke, S.A., “Organic Electroluminescent Diodes,” Appl. Phys. Lett., 51(12):913-915 (1987).
Tung, Yung-Liang et al., “Organic Light-Emitting Diodes Based on Charge-Neutral Ru II PHosphorescent Emitters,” Adv. Mater., 17(8)1059-1064 (2005).
Van Slyke, S. A. et al., “Organic Electroluminescent Devices with Improved Stability,” Appl. Phys. Lett., 69 (15):2160-2162 (1996).
Wang, Y. et al., “Highly Efficient Electroluminescent Materials Based on Fluorinated Organometallic Iridium Compounds,” Appl. Phys. Lett., 79(4):449-451 (2001).
Wong, Keith Man-Chung et al., A Novel Class of Phosphorescent Gold(III) Alkynyl-Based Organic Light-Emitting Devices with Tunable Colour, Chem. Commun., 2906-2908 (2005).
Wong, Wai-Yeung, “Multifunctional Iridium Complexes Based on Carbazole Modules as Highly Efficient Electrophosphors,” Angew. Chem. Int. Ed., 45:7800-7803 (2006).
Related Publications (1)
Number Date Country
20150014649 A1 Jan 2015 US
Provisional Applications (1)
Number Date Country
61846100 Jul 2013 US