Bicarbazole-containing compounds for OLEDs

Abstract

Compound comprising a bicarbazole, the compound having the following formula: where R a and R d can represent mono-, di-, tri- or tetrasubstitutions and R b and R c can represent mono-, di-, or trisubstitutions; where R a , R b , R c , R d , R1 and R2 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl: where only one of R1 and R2 has the following formula: where A and B are independently 5- or 6-membered carbocyclic or heterocyclic rings; where R A and R B Each is independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl; where XS, O or Se.

Description

AREA OF INVENTION

[0001] The present invention relates to organic light-emitting devices (OLEDs). In particular, the present invention relates to phosphorescent organic materials comprising a bicarbazole with a dibenzo or azadibenzo substitution. STATE OF THE ART

[0002] Optoelectronic devices utilizing organic materials are gaining popularity for a number of reasons. Many of the materials used to manufacture such devices are relatively inexpensive, giving organic optoelectronic devices the potential for cost advantages over inorganic devices. Additionally, the inherent characteristics of organic materials, such as their flexibility, make them well-suited for certain applications, such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light-emitting diodes (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. In the case of OLEDs, organic materials can offer performance advantages over conventional materials. For example,The wavelength at which an organic emitter layer emits light can generally be easily adjusted using appropriate dopants.

[0003] OLEDs employ thin organic films that emit light when a voltage is applied across the device. OLEDs are currently considered an increasingly promising technology for applications such as flat panel displays, lighting, and backlighting. Several OLED materials and configurations are described in US patents 5,844,363, 6,303,238, and 5,707,745. International patent applications WO 2011 / 122132 A1, WO 2011 / 125680 A1, and WO2009 / 060742 A1 also relate to OLEDs and materials for OLEDs.

[0004] One application for phosphorescent emitter molecules is a full-color display. Industry standards for such displays specify pixels designed to emit particular colors, also known as "saturated" colors. Specifically, these standards call for pixels with saturated red, green, and blue. Color can be measured using CIE coordinates, which are well-known according to the prior art.

[0005] An example of a green emitter molecule is Tris(2-phenylpyridine)iridium, designated Ir(ppy)3, which has the following structure:

[0006] In this and subsequent figures contained herein, we represent the coordinate bond between nitrogen and metal (here Ir) as a straight line.

[0007] As used herein, the term "organic" encompasses both polymeric materials and organic materials with small molecules used to fabricate organic optoelectronic devices. The term "small molecules" refers to any organic material that is not a polymer, and "small molecules" can indeed be quite large. Small molecules may contain repeating units. The use of a long-chain alkyl group as a substituent, for example, does not exclude a molecule from the class of "small molecules." Small molecules may also be incorporated into polymers, for example, as a side group on a polymer backbone or as part of the backbone itself. Small molecules may also serve as the core unit of a dendrimer, which consists of a series of chemical shells built upon the core unit.The core unit of a dendrimer can be a fluorescent or phosphorescent small molecule emitter. A dendrimer can be a "small molecule," and it is assumed that all dendrimers currently used in OLEDs are small molecules.

[0008] As used herein, "top" means furthest from the substrate, while "bottom" means closest to the substrate. When a first layer is described as "arranged above" a second layer, the first layer is located farther from the substrate. Other layers may also be located between the first and second layers unless it is explicitly stated that the first layer is "in contact with" the second layer. For example, a cathode may be described as "arranged above" an anode, even though various organic layers may be in between.

[0009] As used herein, ‘processable solution’ means capable of being dissolved, dispersed or transported in and / or applied from a liquid medium, either in solution or suspension form.

[0010] A ligand can be described as "photoactive" if it is assumed that the ligand directly contributes to the photoactive properties of an emitter material. A ligand can be described as "ancillary" if it is assumed that the ligand does not contribute to the photoactive properties of an emitter material, although an ancillary ligand can modify the characteristics of a photoactive ligand.

[0011] As used herein and as generally understood by those skilled in the art, a first "highest occupied molecular orbital" (HOMO) or "lowest unoccupied molecular orbital" (LUMO) energy level is "greater than" or "higher than" a second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Since ionization potentials (IP) are measured as negative energy relative to a vacuum level, a higher HOMO energy level corresponds to an IP with a smaller absolute value (an IP that is less negative). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) with a smaller absolute value (an EA that is less negative). In a conventional energy level diagram with the vacuum level on 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.

[0012] As used herein, and as generally understood by those skilled in the art, a first work function is "greater than" or "higher than" a second work function if the first work function has a higher absolute value. Because work functions are generally measured as negative numbers relative to the 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, the "higher" work function is represented as being farther away from the vacuum level in the downward direction. Therefore, the definitions of HOMO and LUMO energy levels follow a different convention than those of work functions.

[0013] More details about OLEDs and the definitions described above can be found in US Patent No. US 7,279,704. SUMMARY OF THE INVENTION

[0014] Compounds containing a bicarbazole are provided. The compounds have the following formula:

[0015] R a , and R d can represent mono-, di-, tri- or tetrasubstitutions, and R b and R c can represent mono-, di-, or trisubstitutions. R a , R b , R c , R d R1 and R2 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Preferably, R1 and R2 are each independently selected from aryl and heteroaryl. Only one of R1 and R2 has the following formula:

[0016] A and B are independently 5- or 6-membered carbocyclic or heterocyclic rings. Preferably, A and B are each independently selected from phenyl and pyridine. R A and R B Each compound is independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. X is S, O, or Se.

[0017] According to one aspect, at least one of R1 and R2 has the following formula:

[0018] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0019] According to another aspect, the compound has the following formula:

[0020] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0021] Specific examples of compounds containing bicarbazole are also provided. In particular, the compound selected from the group consisting of:

[0022] A first device comprising an organic light-emitting device is also provided. The device further comprises an anode, a cathode, and an organic layer arranged between the anode and the cathode. The organic layer comprises a compound comprising bicarbazole, the compound having formula I as described above.

[0023] R a and R d can represent mono-, di-, tri- or tetrasubstitutions, and R b and R c can represent mono-, di-, or trisubstitutions. R a , R b , R c , R d R1 and R2 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Preferably, R1 and R2 are each independently selected from aryl and heteroaryl. Only one of R1 and R2 has the following formula:

[0024] A and B are independently 5- or 6-membered carbocyclic or heterocyclic rings. Preferably, A and B are independently selected from phenyl and pyridine. R A and R B Each compound is independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. X is S, O, or Se.

[0025] According to one aspect, at least one of R1 and R2 has the following formula:

[0026] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0027] According to another aspect, the device includes a Formula II or Formula III connection.

[0028] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from nitrogen and carbon.

[0029] Specific examples of devices containing compounds including bicarbazole are also provided. In particular, the compound is selected from the group consisting of compounds 1 through 6.

[0030] According to one aspect, the organic layer is a blocking layer and the compound of formula I is a blocking material.

[0031] According to another aspect, the organic layer is an emitting layer and the compound of formula I is a host. According to yet another aspect, the emitting layer further comprises a phosphorescent emitting dopant of the following formula:

[0032] According to one aspect, the first device is a consumer product. According to another aspect, the first device is an organic light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] They show: Fig. 1 an organic light-emitting device. Fig. 2 an inverted organic light-emitting device that does not have a separate electron transport layer. Fig. 3 a bicarbazole compound. DETAILED DESCRIPTION

[0034] In general, an OLED comprises at least one organic layer positioned between an anode and a cathode and electrically connected to them. When current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons migrate to the oppositely charged electrode. When an electron and a hole are located on the same molecule, an "exciton" is formed, which is a localized electron / hole pair in an excited energy state. Light is emitted when the exciton relaxes via a photoemitting mechanism. In some cases, the exciton may be localized on an excimer or an exciplex. Non-radiative mechanisms, such as thermal relaxation, can also occur but are generally considered undesirable.

[0035] The original OLEDs used emitter molecules that emit light from the singlet state (“fluorescence”), as disclosed, for example, in US Patent No. 4,769,292. Fluorescence emission generally occurs over a period of less than 10 nanoseconds.

[0036] Recently, OLEDs with emitter materials that emit light from the triplet state (“phosphorescence”) have been described. See Baldo et al., “High-efficiency phosphorescent emission from organic electroluminescent devices,” 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”). The phosphorescence is described in detail in US Patent No. US 7,279,704, columns 5–6.

[0037] Fig.Figure 1 shows an organic light-emitting device 100. The figures are not necessarily drawn to scale. The device 100 can contain a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron-blocking layer 130, an emitting layer 135, a hole-blocking layer 140, an electron transport layer 145, an electron injection layer 150, a protective layer 155, and a cathode 160. The cathode 160 is a compound cathode with a first conductive layer 162 and a second conductive layer 164. The device 100 can be manufactured by applying the described layers in sequence. The properties and functions of these various layers, as well as exemplary materials, are described in detail in columns 6-10 of US Patent US 7,279,704.

[0038] Further examples are available for each of these layers. For example, a flexible and transparent substrate / anode combination is disclosed in US Patent No. 5,844,363. An example of a p-doped hole transport layer is m-MTDATA doped with F.sub.4-TCNQ in a molar ratio of 50:1, as disclosed in US Patent Publication No. 2003 / 0230980. Examples of emitter and host materials are disclosed in US Patent No. 6,303,238, granted to Thompson et al. An example of an n-doped electron transport layer is BPhen doped with Li in a molar ratio of 1:1, as disclosed in US Patent Publication No. 2003 / 0230980. US patents No. US 5,703,436 and US 5,707,745 disclose examples of cathodes, including compound cathodes, with a thin layer of metal, such as Mg:Ag, with an overlying, transparent, electrically conductive ITO layer applied by sputtering.The theory and use of blocking layers are described in detail in US Patent No. 6,097,147 and US Patent Publication No. 2003 / 0230980. Examples of injection layers are provided in US Patent Publication No. 2004 / 0174116. A description of protective layers can be found in US Patent Publication No. 2004 / 0174116.

[0039] Fig.Figure 2 shows an inverted OLED 200. The device comprises a substrate 210, a cathode 215, an emitter layer 220, a hole transport layer 225, and an anode 230. The device 200 can be fabricated by depositing the described layers sequentially. Since the most conventional OLED configuration has a cathode positioned above the anode, and the device 200 has a cathode 215 positioned below the anode 230, the device 200 can be described as an "inverted" OLED. Similar materials to those described with respect to the device 100 can be used in the corresponding layers of the device 200. Fig. Figure 2 provides an example of how some layers in the structure of device 100 can be omitted.

[0040] The in Fig. 1 and Fig.The simple layer structure shown in Figure 2 is provided by a non-limiting example, and it is understood that the embodiments of the invention can be used in conjunction with a wide variety of other structures. The specific materials and structures described are exemplary, and other materials and structures can also be used. Functional OLEDs can be achieved by combining the described layers in various ways, or layers can be omitted based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials not specifically described may be used. Although many of the examples provided herein describe different layers with a single material, it is understood that combinations of materials, such as...A mixture of host and dopant, or more generally any mixture, can be used. The layers can also have different sublayers. The various names given to the layers herein are not considered strictly restrictive. For example, in device 200, the hole transport layer 225 transports holes and injects holes into the emitting layer 220 and can be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED can, according to the description, have an “organic layer” arranged between a cathode and an anode. This organic layer can comprise a single layer or can further comprise several layers of different organic materials as described, such as, for example, in relation to… Fig. 1 and Fig. 2.

[0041] Structures and materials not specifically described can also be used, such as polymer-based OLEDs (PLEDs), like those described in US Patent No. 5,247,190, granted to Friend et al. Another example is the use of OLEDs with a single organic layer. The OLEDs can also be stacked, as described in US Patent No. 5,707,745, granted to Forrest et al. The OLED structure can be derived from the one described in Fig. 1 and Fig. The substrate may differ from the simply layered structure shown in Figure 2. For example, it may contain an angled, reflective surface to improve coupling, such as a mesa structure as described in US Patent No. 6,091,195, granted to Forrest et al., and / or a pit structure as described in US Patent No. 5,834,893, granted to Bulovic et al.

[0042] Unless otherwise specified, any layers of the various embodiments may be applied by any method. For the organic layers, preferred methods include thermal evaporation, inkjet printing (as described, for example, in US Patents 6,013,982 and 6,087,196), organic vapor deposition (OVPD) (as described, for example, in US Patent 6,337,102, granted to Forrest et al.), and deposition by organic vapor jet printing (OVJP) (as described, for example, in US Patent Application Serial No. 10 / 233,470). Other suitable deposition methods include spin coating and other solvent-based methods. Solvent-based methods are preferably carried out in a nitrogen or inert atmosphere. For the other layers, thermal evaporation is a preferred method. Preferred structuring methods include mask application and cold welding (as described, for example, in US Patent 6,337,102, granted to Forrest et al.).Patents US 6,294,398 and US 6,468,819 describe the patterning associated with some of the deposition methods, such as inkjet and OVJD. Other methods may also be used. The materials to be deposited may be modified to be compatible with a particular deposition method. Substituents, such as alkyl and aryl groups, branched or unbranched and preferably containing at least three carbons, may be used, for example, in small molecules to improve their solvent processing capability. Substituents with 20 or more carbons may also be used, and a preferred range consists of 3 to 20 carbons. Materials with asymmetric structures may exhibit better solvent processing capability than those with symmetric structures because asymmetric materials may have a lower tendency to recrystallize.Dendrimer substituents can be used to improve the ability of small molecules to undergo solvent processing.

[0043] Devices manufactured according to the embodiments of the invention can be incorporated into a wide variety of consumer products, including flat panel displays, computer monitors, televisions, billboards, indoor or outdoor lighting fixtures and / or displays, news displays, fully transparent displays, flexible displays, laser printers, telephones, mobile phones, personal digital assistants (PDAs), laptop computers, digital cameras, camcorders, viewfinders, microdisplays, vehicles, large-format displays, cinema or stadium screens, or signs. Various control mechanisms can be used to control the devices manufactured according to the present invention, including a passive matrix and an active matrix. Many of the devices are intended for use in a temperature range comfortable for humans, such as…18 degrees C to 30 degrees C and especially preferably at room temperature (20-25 degrees C).

[0044] The materials and structures described herein can also be used in devices other than OLEDs. Other optoelectronic devices, such as organic solar cells and organic photodetectors, can utilize these materials and structures. More generally, organic devices, such as organic transistors, can employ these materials and structures.

[0045] The terms halo, halogen, alkyl, cycloalkyl, alkenyl, alkynyl, arylcyl, heterocyclic group, aryl, aromatic group and heteroaryl are known according to the prior art and are defined in US 7,279,704 in columns 31-32.

[0046] Novel bicarbazole-containing compounds are provided (shown in Fig.3) The compounds can be used as host materials or blocking materials for phosphorescent OLEDs. The compounds contain a 3,3'-bicarbazole core substituted at the 9th position by one of dibenzofuran, dibenzothiophene, dibenzosolenophene, azadibenzofuran, azadibenzothiophene, or azadibenzoselenophene.

[0047] Carbazole is a well-known base component for OLED materials. In particular, compounds containing 3,3'-bicarbazole exhibit good hole transport properties but poor electron stability. 3,3'-Bicarbazole, for example, has a flatter HOMO than 9-arylcarbazole. Additionally, while alkyl- and aryl-substituted 3,3'-bicarbazole compounds have been used as hole transport layer materials and hosts for OLEDs, these compounds also exhibit poor electron stability and can therefore provide devices with limited lifetimes. A diaryl-substituted 3,3'-bicarbazole, i.e., H1, has, for example, a HOMO of about 5.6 eV, which is very good for hole transport but poor for electron stability. Therefore, the 3,3'-bicarbazole compounds found in the literature provide devices with limited lifetimes.

[0048] According to the present invention, 3,3'-bicarbazole compounds are substituted at the 9th position with one of dibenzofuran, dibenzothiophene, dibenzoselenophene, azadibenzofuran, azadibenzothiophene, or azadibenzoselenophene. These substituents adjust the HOMO / LUMO levels and increase the stability of the compound towards electrons, thereby providing OLEDs with improved stability. In particular, azadibenzo-substituted bicarbazoles can be more electron-transporting than dibenzo-substituted bicarbazoles and can thus provide devices with a lower operating voltage. Additionally, the bicarbazole compounds provided herein can be advantageously used as a blocking layer material and as a host material. Therefore, the 3,3'-bicarbazole compounds substituted at the 9th position can be used as a blocking layer material and as a host material.Positions substituted with a dibenzo or azadibenzo group provide devices with improved service life and increased efficiency.

[0049] Compounds containing a bicarbazole are provided. The compounds have the following formula:

[0050] R a and R d can represent mono-, di-, tri- or tetrasubstitutions, and R b and R c can represent mono-, di-, or trisubstitutions. R a , R b , R c , R d R1 and R2 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Preferably, R1 and R2 are each independently selected from the group consisting of aryl and heteroaryl. At least one of R1 and R2 has the following formula:

[0051] A and B are independently 5- or 6-membered carbocyclic or heterocyclic rings. Preferably, A and B are each independently selected from phenyl and pyridine. R A and R B Each compound is independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. X is S, O, or Se.

[0052] According to one aspect, at least one of R1 and R2 has the following formula:

[0053] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0054] According to one aspect, one of R1 and R2 is selected from the group consisting of:

[0055] R'1 and R'2 are independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl.

[0056] According to another aspect, the compound has the following formula:

[0057] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0058] Specific examples of compounds containing bicarbazole are also provided. In particular, the compound selected from the group consisting of:

[0059] A first device comprising an organic light-emitting device is also provided. The device further comprises an anode, a cathode, and an organic layer arranged between the anode and the cathode. The organic layer comprises a compound comprising bicarbazole, the compound having the following formula:

[0060] R a and R d can represent mono-, di-, tri- or tetrasubstitutions, and R b and R c can represent mono-, di-, and trisubstitutions. R a , R b , R c , R d R1 and R2 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Preferably, R1 and R2 are each independently selected from the group consisting of aryl and heteroaryl. Only one of R1 and R2 has the following formula:

[0061] A and B are independently 5- or 6-membered carbocyclic or heterocyclic rings. Preferably, A and B are independently selected from phenyl and pyridine. R A and R B Each compound is independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. X is S, O, or Se.

[0062] According to one aspect, at least one of R1 and R2 has the following formula:

[0063] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0064] According to one aspect, one of R1 and R2 is selected from the group consisting of:

[0065] R'1 and R'2 are independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl.

[0066] According to another aspect, the device comprises a combination of the following formula:

[0067] R A and R B can represent mono-, di-, tri-, or tetrasubstitutions. R A and R B Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl, and heteroaryl. Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8 are independently selected from nitrogen and carbon.

[0068] Specific examples of devices containing compounds including bicarbazole are also provided. In particular, the compound is selected from the group consisting of:

[0069] According to one aspect, the organic layer is a blocking layer and the compound of formula I is a blocking material.

[0070] According to another aspect, the organic layer is an emitter layer and the compound of formula I is a host. According to yet another aspect, the emitter layer further comprises a phosphorescent emitter dopant of the following formula:

[0071] According to one aspect, the first device is a consumer product. According to another aspect, the first device is an organic light-emitting device.

[0072] The materials described herein as useful for a particular layer in an organic light-emitting device can be used in combination with a wide variety of other materials present in the device. The emitting dopants disclosed herein can, for example, 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 subsequently mentioned are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and those skilled in the art will be able to consult the literature to identify other materials that may be useful in combination.

[0073] In addition to and / or in combination with the materials disclosed herein, many hole injection materials, hole transport materials, host materials, dopants, exciton / hole blocking layer materials, electron transport and electron injection materials can be used in an OLED. Non-limiting examples of materials that can be used in an OLED in combination with the materials disclosed herein are listed below. HIL / HTL:

[0074] The hole injection / transport material to be used in the present invention is not necessarily limited, and any compound may be used as long as it is typically used as a hole injection / transport material. Examples of the material include, but are not limited to: a phthalocyanine or porphyrin derivative; an aromatic amine derivative; an indolecarbazole derivative; a fluorocarbon polymer; a polymer containing conductive dopants; a conductive polymer, such as PEDOT / PSS; a self-assembling monomer derived from compounds such as phosphonic acid and silane derivatives; a metal oxide derivative, such as MoO₂. x ; a semiconducting organic compound of the p-type, such as 1,4,5,8,9,12-hexaazatriphenylenehexacarbonitril; a metal complex and a cross-linkable compound.

[0075] Examples of aromatic amine derivatives used in HIL or HTL include, but are not limited to, the following general structures:

[0076] Each of the Ar 1 to Ar 9is selected from the group consisting of aromatic, cyclic hydrocarbon compounds, such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalen, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene;aus der Gruppe bestehend aus aromatischen heterozyklischen Verbindungen, wie z.B. Dibenzothiophen, Dibenzofuran, Dibenzoselenophen, Furan, Thiophen, Benzofuran, Benzothiophen, Benzoselenophen, Carbazol, Indolcarbazol, Pyridylindol, Pyrrolodipyridin, Pyrazol, Imidazol, Triazol, Oxazol, Thiazol, Oxadiazol, Oxatriazol, Dioxazol, Thiadiazol, Pyridin, Pyridazin, Pyrimidin, Pyrazin, Triazin, Oxazin, Oxathiazin, Oxadiazin, Indol, Benzimidazol, Indazol, Indoxazin, Benzoxazol, Benziosoxazol, Benzthiazol, Quinolin, Isoquinolin, Cinnolin, Quinazolin, Quinoxalin, Naphthyridin, Phthalazin, Pteridin, Xanthen, Acridin, Phenazin, Phenothiazin, Phenoxazin, Benzofuropyridin, Furodipyridin, Benzothienopyridin, Thiendipyridin, Benzoselenphenopyridin und Selenphenodipyridin;and from the group consisting of 2 to 10 cyclic structural units, which are groups of the same type or of different types, selected from the aromatic cyclic hydrocarbon group and from the aromatic heterocyclic group, and which are linked directly or via at least one 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, alkyl, alkoxy, amino, alkenyl, alkynyl, arylalkyl, heteroalkyl, aryl and heteroaryl.

[0077] According to one aspect, Ar 1 to Ar 9 Selected independently from the group consisting of:

[0078] k is an integer from 1 to 20; X 1 up to X 8 is CH or N; Ar 1exhibits the same group as defined above.

[0079] Examples of metal complexes used in HIL or HTL include, but are not limited to, the following general formula:

[0080] M is a metal that has an atomic weight of more than 40; (Y 1 - Y 2 ) a bidentate ligand, Y1 and Y 2 are independently selected from C, N, O, P and S; L is an ancillary ligand; m is an integer value from 1 to the maximum number of ligands that can be attached to the metal; and m+n is the maximum number of ligands that can be attached to the metal.

[0081] According to one aspect, (Y 1 - Y 2 ) a 2-phenylpyridine derivative.

[0082] According to another aspect, (Y 1 - Y 2 ) a carbene ligand.

[0083] According to another aspect, M is selected from Ir, Pt, Os and Zn.

[0084] According to another aspect, the metal complex exhibits the lowest oxidation potential in solution towards Fc. + / Fc coupling of less than approximately 0.6 V.

[0085] Host:

[0086] The light-emitting layer of the organic EL device of the present invention preferably contains at least one metal complex as a light-emitting material and can contain a host material that uses the metal complex as a dopant. Examples of the host material are not necessarily limiting, and any metal complexes or organic compounds can be used as long as the triplet energy of the host is greater than that of the dopant.

[0087] Examples of metal complexes used as hosts preferably have the following general formula:

[0088] M is a metal; (Y 3 - Y 4 ) is a bidentate ligand, Y3 and Y 4 are each independently selected from C, N, O, P and S; L is an ancillary ligand; m is an integer value from 1 to the maximum number of ligands that can be attached to the metal; and m+n is the maximum number of ligands that can be attached to the metal.

[0089] According to one aspect, the metal complexes are:

[0090] (O - N) is a bidentate ligand with a metal coordinated to the atoms O and N.

[0091] According to another aspect, M is selected from Ir and Pt.

[0092] According to another aspect, (Y 3 - Y 4 ) a carbene ligand.

[0093] Examples of organic compounds used as hosts are selected from the group consisting of aromatic, cyclic hydrocarbons such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalen, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene;aus der Gruppe bestehend aus aromatischen heterozyklischen Verbindungen, wie z.B. Dibenzothiophen, Dibenzofuran, Dibenzoselenophen, Furan, Thiophen, Benzofuran, Benzothiophen, Benzoselenophen, Carbazol, Indolcarbazol, Pyridylindol, Pyrrolodipyridin, Pyrazol, Imidazol, Triazol, Oxazol, Thiazol, Oxadiazol, Oxatriazol, Dioxazol, Thiadiazol, Pyridin, Pyridazin, Pyrimidin, Pyrazin, Triazin, Oxazin, Oxathiazin, Oxadiazin, Indol, Benzimidazol, Indazol, Indoxazin, Benzoxazol, Benzisoxazol, Benzthiazol, Quinolin, Isoquinolin, Cinnolin, Quinazolin, Quinoxalin, Naphthyridin, Phthalazin, Pteridin, Xanthen, Acridin, Phenazin, Phenothiazin, Phenoxazin, Benzofuropyridin, Furodipyridin, Benzothienopyridin, Thiendipyridin, Benzoselenphenopyridin und Selenphenodipyridin;and from the group consisting of 2 to 10 cyclic structural units, which are groups of the same or different types, selected from the aromatic cyclic hydrocarbon group and the aromatic heterocyclic group, and which are linked directly or via at least one oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit, and the aliphatic cyclic group. Each group is further substituted by a substituent selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, arylalkyl, heteroalkyl, aryl, and heteroaryl.

[0094] According to one aspect, the host compound contains at least one of the following groups in the molecule:

[0095] R 1 to R 7are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, arylalkyl, heteroalkyl, aryl and heteroaryl; if it is aryl or heteroaryl, it has a similar definition to the Ar's mentioned above.

[0096] k is an integer from 0 to 20.

[0097] X 1 up to X 8 is selected from CH or N. HBL:

[0098] A hole-blocking layer (HBL) can be used to reduce the number of holes and / or excitons that escape the emitter layer. The presence of such a blocking layer in a device can lead to significantly higher efficiencies compared to a similar device without a blocking layer. A blocking layer can also be used to restrict emission to a desired region of an OLED.

[0099] According to one aspect, the compound used in HBL contains the same molecule that is used as a host, as described above.

[0100] According to another aspect, the compound used in HBL contains at least one of the following groups in the molecule:

[0101] k is an integer from 0 to 20; L is an ancillary ligand, m is an integer from 1 to 3. ETL:

[0102] The electron transport layer (ETL) can contain a material capable of transporting electrons. The ETL can be intrinsic (undoped) or doped. Doping can be used to improve conductivity. Examples of ETL materials are not necessarily limiting, and any metal complex or organic compound can be used, as long as it is typically used to transport electrons.

[0103] According to one aspect, the compound used in the ETL contains at least one of the following groups in the molecule:

[0104] R 1 is selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, arylalkyl, heteroalkyl, aryl and heteroaryl; if it is aryl or heteroaryl, it has a similar definition to the Ar's mentioned above.

[0105] Ar 1 to Ar 3 have a similar definition to the Ar's mentioned above.

[0106] k is an integer from 0 to 20.

[0107] X 1 up to X 8 is selected from CH or N.

[0108] According to another aspect, the metal complexes used in the ETL, without being limited to these, include the following general formula:

[0109] (O - N) or (N - N) is a bidentate ligand with a metal that coordinates with the atoms O, N or N, N; L is an ancillary ligand; m is an integer from 1 to the maximum number of ligands that can be attached to the metal. EXPERIMENTS Examples of connections

[0110] Example 1. Synthesis of compound 1

[0111] Synthesis of 9-phenylcarbazole. Pd₂(dba)₃ (1.095 g, 1.196 mmol) and tri-tert-butylphosphine (4.78 mL, 4.78 mmol, 1.0 M in toluene) were mixed in 400 mL of xylene. The mixture was stirred under nitrogen for 20 minutes. 9H-carbazole (20 g, 120 mmol), bromobenzene (28.2 g, 179 mmol), 18-crown-6 (3.16 g, 11.96 mmol), and potassium carbonate (24.80 g, 179 mmol) were then added sequentially, and the mixture was heated under nitrogen for 18 hours until reflux. The xylene solution was decanted. The solvent was evaporated, and the residue was purified by vacuum distillation. After purification, 22.3 g (97% yield) of product was obtained.

[0112] Synthesis of 3-bromo-9-phenylcarbazole. NBS (19.31 g, 109 mmol) in DMF was added dropwise to 9-phenyl-9H-carbazole (24 g, 99 mmol) in 200 mL at 0 °C. The reaction was monitored by HPLC. The reaction was quenched by adding 500 mL of water after 2 hours. After stirring for 24 hours at room temperature, the clear solution was decanted, and the solid residue was dissolved in dichloromethane and washed with water and LiCl solution. The solution was dried with MgSO4, and the solvent was evaporated. The residue was used for the next step without further purification. The product contains the starting material, monobromo, and dibromo. 31 g of product were obtained.

[0113] Synthesis of 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole. 3-Bromo-9-phenyl-9H-carbazole (30 g, 93 mmol), 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi(1,3,2-dioxaborolane) (47.3 g, 186 mmol), and potassium acetate (22.85 g, 233 mmol) were added to 400 mL of dioxane. Nitrogen was added to the solution for 20 minutes, producing bubbles. Pd(dppf)Cl₂ (2.281 g, 2.79 mmol) was added, and the reaction mixture was heated to 80 °C for 6 hours. The reaction was monitored by TLC. After cooling to room temperature, the reaction was filtered through a silica gel plug. The diboron was removed by vacuum distillation at 160 °C. The residue was coated on Celite and purified by column evaporation using 2% ethyl acetate and hexanes as solvents. Purification yielded 16.5 g of product.

[0114] Synthesis of 3-bromocarbazole. NBS (12.77 g, 71.8 mmol) in DMF was added dropwise to 9H-carbazole (12 g, 71.8 mmol) in 200 mL at 0 °C. The reaction was monitored by HPLC. After 2 hours, the HPLC showed 76% of the desired product and 6% of a dibrominated compound. The reaction was quenched by adding 500 mL of ice water. The internal temperature was maintained below 10 °C. The precipitate was collected by filtration. The solid was stirred in 400 mL of warm methanol (~40 °C). The solid was collected by filtration. The solid was dissolved in 150 mL of DCM. 200 mL of methanol was added. The DCM was boiled. The solvent was at

[0115] The solution was reduced to 150 ml. The slurry was stirred overnight at room temperature. The solid was collected by filtration. 9 g (51% yield) of solid was collected.

[0116] Synthesis of 9-phenyl-9H,9'H-3,3'-bicarbazole. A mixture of 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (12 g, 32.5 mmol), 3-bromo-9H-carbazole (6.66 g, 27.1 mmol) and potassium phosphate (34.5 g, 162 mmol) in 500 ml toluene and 50 ml H2O was exposed to N2 for 20 minutes to induce bubbling. Dicyclohexyl (2',6'-dimethoxybiphenyl-2-yl)phosphine (0.445 g, 1.083 mmol) and Pd₂(dba)₃ (0.248 g, 0.271 mmol) were then added, and the mixture was heated under nitrogen for 25 hours until reflux. The TLC indicated that the reaction was complete. The reaction was extracted with dichloromethane, washed with alkali, and dried with magnesium sulfate. The solution was heated to boiling. Hexane was added. The dichloromethane was boiled off, and the volume of hexane reached approximately 1200 mL. A precipitate formed during the boiling of the dichloromethane. The solution was cooled to room temperature and stirred overnight.The precipitate was filtered, dissolved in THF, and passed through a short silica gel plug. After drying under vacuum at 60 °C, 9.6 g (87%) of product was obtained.

[0117] Synthesis of Compound 1. A mixture of 2-ioddibenzo[b,d]furan (2.59 g, 8.81 mmol), 9-phenyl-9H,9'H-3,3'-bicarbazole (3 g, 7.34 mmol), and sodium tert-butoxide (1.764 g, 18.36 mmol) in 200 mL of xylene was purged with nitrogen for 20 minutes. Dicyclohexyl(2',6'-dimethoxybiphenyl-2-yl)phosphine (0.121 g, 0.294 mmol) and Pd₂(dba)₃ (0.067 g, 0.073 mmol) were then added, and the mixture was heated under nitrogen for 24 hours until reflux. The mixture was cooled and filtered through Celite. After solvent evaporation, the residue was coated with Celite and purified by column chromatography. 3.7 g of product was obtained after the column.

[0118] Example 2. Synthesis of compound 2.

[0119] Synthesis of Compound 2. A mixture of 2-bromodibenzo[b,d]thiophene (3.22 g, 12.24 mmol), 9-phenyl-9H,9'H-3,3'-bicarbazole (2.5 g, 6.12 mmol), and sodium tert-butoxide (1.764 g, 18.36 mmol) in 100 mL of xylene was purged with nitrogen for 20 minutes. Pd₂(dba)₃ (0.056 g, 0.061 mmol) and dicyclohexyl(2',6'-dimethoxybiphenyl-2-yl)phosphine (0.100 g, 0.245 mmol) were then added, and the mixture was purged with nitrogen for another 20 minutes. The reaction mixture was refluxed under nitrogen for 24 hours. The mixture was cooled and filtered through Celite. After solvent evaporation, the residue was coated on Celite and purified by column chromatography using up to 50% dichloromethane in hexane as solvent. 9-(Dibenzo[b,d]thiophen-2-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (2.1 g, 3.55 mmol, 58.1% yield) was obtained.

[0120] Example 3. Synthesis of compound 3.

[0121] Synthesis of Compound 3. A mixture of 4-bromodibenzo[b,d]thiophene (2.061 g, 7.83 mmol), 9-phenyl-9H,9'H-3,3'-bicarbazole (2 g, 4.90 mmol), and sodium tert-butoxide (1.412 g, 14.69 mmol) in 200 ml of xylene was purged with nitrogen for 20 minutes. Pd2(dba)3 (0.045 g, 0.049 mmol) and dicyclohexyl(2',6'-dimethoxybiphenyl-2-yl)phosphine (0.080 g, 0.196 mmol) were added and purged with nitrogen for another 20 minutes. The mixture was then heated under nitrogen until reflux for 24 hours. The mixture was cooled and filtered through Celite. After solvent evaporation, the residue was coated on Celite and purified by column chromatography using 2:3 dichloromethane and hexanes as solvents. 9-(Dibenzo[b,d]thiophen-4-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (2.2 g, 3.72 mmol, 76% yield) was obtained. The product was further purified by recrystallization with dichloromethane and hexane.

[0122] Example 4. Synthesis of compound 4.

[0123] Synthesis of Compound 4. A mixture of 4-chloro-3-azadibenzothiophene (2.58 g, 11.75 mmol), 9-phenyl-9H,9'H-3,3'-bicarbazole (4 g, 9.79 mmol), and sodium tert-butoxide (2.353 g, 24.48 mmol) in 200 ml of xylene was purged with nitrogen for 20 minutes. Dicyclohexyl(2',6'-dimethoxybiphenyl-2-yl)phosphine (0.161 g, 0.392 mmol) and Pd₂(dba)₃ (0.090 g, 0.098 mmol) were then added, and the mixture was heated under nitrogen for 14 hours until reflux. The mixture was cooled and filtered through a Celite stopper. After solvent evaporation, the residue was coated on Celite and purified by column chromatography with 1:1 dichloromethane and hexanes up to 2:1 dichloromethane and hexanes. 3.8 g of product were obtained after column chromatography.

[0124] Example 5. Synthesis of compound 5.

[0125] Synthesis of 3-azido-2-chloro-4-iodopyridine. 2-Chloro-3-iodopyridine (8 g, 33 mmol) was added to 300 mL of THF under an inert environment, and the reaction mixture was cooled to -78 °C. Lithium diisopropylamide (2 M solution in THF, 17 mL, 33 mmol) was added dropwise to the reaction mixture, and after completion, the THF solution was stirred at -78 °C for 1 hour. A solution of 2,4,6-triisopropylbenzenesulfonyl azide (15.5 g, 50 mmol) in 50 mL of THF was then slowly added to the reaction mixture, and the mixture was stirred at -78 °C for another hour. The reaction flask was then slowly warmed to room temperature. The reaction mixture was quenched with 10 mL of saturated NH4Cl solution. Most of the organic solvent was evaporated under vacuum. The crude product was separated between lye and ethyl acetate. The organic layer was isolated and treated with anhd.Na₂SO₄ was dried and subsequently purified by silica gel column chromatography using 2–10% ethyl acetate / hexane as eluent. 3-Azide-2-chloro-4-iodopyridine (25 mmol, 7 g, 75% yield) was isolated as a pale yellow crystalline solid.

[0126] Synthesis of 2-chloro-4-iodo-N-(triphenylphosphoranylidene)pyridine-3-amine. 3-Azido-2-chloro-4-iodopyridine (7 g, 25 mmol) and triphenylphosphine (8.5 g, 32 mmol) were stirred in 100 ml of a 1:1 mixture of THF and water until the azide starting material disappeared in the TLC. Most of the THF was then removed under vacuum. The crude product separated between the base and ethyl acetate. The organic layer was isolated, dried over anhydrous Na₂SO₄, and purified by silica gel column chromatography using 5–40% ethyl acetate and hexanes as eluents. 2-Chloro-4-iodo-N-(triphenylphosphoranylidene)pyridine-3-amine (12 g, 23 mmol, 93 % yield) was isolated as a crystalline white solid.

[0127] Synthesis of 2-chloro-4-(2-methoxyphenyl)pyridine-3-amine. 2-chloro-4-iodo-N-(triphenylphosphoranylidene)pyridine-3-amine (12 g, 23 mmol), (2-methoxyphenyl) boric acid (4.25 g, 28 mmol), and 2M potassium carbonate solution (46.6 ml, 93 mmol) were poured into 120 ml of DME and degassed by blowing through with nitrogen for 15 minutes. Tetrakisphosphine palladium(0) (1.35 g, 1.12 mmol) was added to the stirred solution, and the reaction mixture was degassed for a further 10 minutes. The reaction mixture was then refluxed for 48 hours. The cooled reaction mixture was separated between ethyl acetate and alkali. The organic layer was isolated and dissolved by anhydrous... Na₂SO₄ was dried and purified by silica gel column chromatography using 5–30% ethyl acetate / hexanes as eluent. 2-Chloro-4-(2-methoxyphenyl)pyridine-3-amine (4.3 g, 18 mmol, 78% yield) was isolated as a liquid oil, which transformed into white crystals upon standing at room temperature.

[0128] Synthesis of 1-chlorobenzofuro[2,3-c]pyridine. 2-chloro-4(2-methoxyphenyl)pyridine-3-amine (4.3 g, 18 mmol) was dissolved in 91 mL of glacial acetic acid and concentrated sulfuric acid (0.503 mL, 18.11 mmol). 2-Methyl-2-nitropropane (6.22 g, 54.3 mmol) was added dropwise to the reaction mixture at room temperature. The reaction mixture was stirred at 45 °C until the starting material disappeared in GC. After completion of the reaction, most of the acetic acid was distilled off under vacuum, and the crude product was diluted with DCM. The organic residue was partitioned between the DCM and Na₂CO₃ solution. The organic layer was isolated, washed with alkali, dried over anhydrous Na₂SO₄, and the solvents were evaporated under vacuum. The crude product was purified by silica gel column chromatography using 10–30% ethyl acetate / hexanes as eluent. 1.5 g of 1-chlorobenzofuro[2,3-c]pyridine was isolated as a white solid in 41% yield.

[0129] Synthesis of Compound 5. A mixture of 1-chlorobenzofuro[2,3-c]pyridine (1.45 g, 7.12 mmol), 9-phenyl-9H,9'H-3,3'bicarbazole (3.49 g, 8.55 mmol), and sodium 2-methylpropan-2-olate (1.711 g, 17.80 mmol) in 150 ml of xylene was purged with nitrogen for 20 minutes. Dicyclohexyl(2',6'-dimethoxy-[1,1'-biphenyl]-2-yl)phosphine (0.117 g, 0.285 mmol) and Pd2(dba)3 (0.065 g, 0.071 mmol) were then added, and the mixture was heated under nitrogen for 14 hours until reflux. The mixture was cooled and filtered through a Celite stopper. After solvent evaporation, the residue was coated on Celite and purified by column chromatography with 1:1 dichloromethane and hexanes up to 3:2 dichloromethane and hexanes. 4 g (98% yield) of product were obtained. Examples of devices

[0130] All device examples were produced by high-vacuum thermal evaporation (<10 -7Torr). The anode electrode is 800 Å indium tin oxide (ITO). The cathode consisted of 10 Å LiF followed by 1000 Å Al. All devices were encapsulated with a glass lid, which was sealed with an epoxy resin in a nitrogen glove box (<1 ppm of H₂O and O₂) immediately after manufacture. A moisture-trapping agent was incorporated into the packaging.

[0131] The organic stack of devices consisted, successively from the ITO surface, of 100 Å of compound B as the hole injection layer (HIL), 300 Å of 4,4'-bis[N-(1-Naphthyl)-N-phenylamino]biphenyl (α-NPD) as the hole transport layer (HTL), 300 Å of a host doped with 15% or 9% of compound C as the emitter layer (EML), 50 Å of BL and 400 Å of Alq3 (Tris-8-hydroxyquinolinaluminium) as the ETL.

[0132] Comparative examples of devices were manufactured similarly to the device examples, except that H1 or H2 was used as the host.

[0133] As used herein, the compounds exhibit the following structures:

[0134] Special materials are provided for use in an OLED. In particular, the materials can be used as a host or as a blocking layer. The device structures are provided in Table 1, and the corresponding measured device data are provided in Table 2. Devices featuring an emitter layer comprising compounds 1–5 show improved efficiency and lifetime. Furthermore, devices featuring a blocking layer comprising compound 5 also show improved lifetime and efficiency. TABLE 1 Example HIL HTL EML (doping %) BL ETL Example 1 E1 NPD Connection 1 E29% Connection 1 Alq Example 2 E1 NPD Connection 1 E29% H2 Alq Example 3 E1 NPD Connection 1 E2 15 % Connection 1 Alq Example 4 E1 NPD Connection 1 E2 15 % H2 Alq Example 5 E1 NPD Connection 2 E29% Connection 2 Alq Example 6 E1 NPD Connection 2 E29% H2 Alq Example 7 E1 NPD Connection 2 E2 15 % Connection 2 Alq Example 8 E1 NPD Connection 2 E2 15 % H2 Alq Example 9 E1 NPD Connection 3 E29% Connection 3 Alq Example 10 E1 NPD Connection 3 E2 9 % H2 Alq Example 11 E1 NPD Connection 3 E29% Connection 4 Alq Example 12 E1 NPD Connection 3 E2 15 % Connection 3 Alq Example 13 E1 NPD Connection 3 E2 15 % H2 Alq Example 14 E1 NPD Connection 3 E2 15 % Connection 4 Alq Example 15 E1 NPD Connection 4 E29% Connection 4 Alq Example 16 E1 NPD Connection 4 E29% H2 Alq Example 17 E1 NPD Connection 4 E2 15 % Connection 4 Alq Example 18 E1 NPD Connection 4 E2 15 % H2 Alq Example 19 E1 NPD H2 E2 15 % Connection 4 Alq Example 20 E1 NPD Connection 5 E29% Connection 5 Alq Example 21 E1 NPD Connection 5 E29% H2 Alq Example 22 E1 NPD Connection 5 E2 15 % Connection 5 Alq Example 23 E1 NPD Connection 5 E2 15 % H2 Alq Comparison Example 1 E1 NPD H1 E29% H1 Alq Comparison E1 NPD H1 E29% H2 Alq Example 2 Comparison Example 3 E1 NPD H1 E2 15 % H1 Alq Comparison Example 4 E1 NPD H1 E2 15 % H2 Alq Comparison Example 5 E1 NPD H2 E2 15 % H2 Alq TABLE 2 1931 CIE At 1000 nits At 2000 nits Example × y λ max FWHM (nm) Voltage (V) LE (Cd / A) EQE (%) PE (Im / W) LT 80% (h) Example 1 0,186 0,408 474 60 8,9 27,3 11,6 9,6 122 Example 2 0,185 0,405 474 60 6,8 33,1 14,1 15,3 185 Example 3 0,186 0,409 474 60 8,1 22,1 9,3 8,5 60 Example 4 0,182 0,400 474 58 6,1 43,2 18,6 22,4 115 Example 5 0,186 0,415 474 62 8,8 26,7 11,2 9,5 68 Example 6 0,185 0,411 474 62 7 32,3 13,6 14,6 123 Example 7 0,187 0,413 474 62 8,1 21,2 8,9 8,2 29 Example 8 0,183 0,405 474 60 6,2 42,3 18 21,6 90 Example 9 0,186 0,410 474 60 8,8 27 11,4 9,6 244 Example 10 0,185 0,406 474 60 7,4 31,2 13,3 13,2 350 Example 11 0,185 0,407 474 60 7,1 32,2 13,7 14,3 282 Example 12 0,185 0,409 474 60 7,7 28,3 12 11,5 270 Example 13 0,182 0,403 474 60 6,4 42,7 18,3 21,0 310 Example 14 0,182 0,403 474 60 6,2 44,9 19,3 22,7 305 Example 15 0,207 0,441 474 76 7 19,4 7,7 8,7 60 Example 16 0,206 0,439 474 74 7,5 19,9 7,9 8,3 55 Example 17 0,212 0,448 474 78 6,1 26,3 10,3 13,5 92 Example 18 0,211 0,446 474 76 6,5 27 10,6 13,0 64 Example 19 0,180 0,394 474 58 5,6 45,4 19,8 25,5 230 Example 20 0,196 0,430 474 66 7,1 23,3 9,4 10,3 30 Example 21 0,194 0,425 474 64 7,2 23,8 9,7 10,3 28 Example 22 0,196 0,432 474 66 6,2 29,6 12 14,9 28 Example 23 0,195 0,427 474 64 6,4 30,6 12,5 15,0 24 Comparison Example 1 0,210 0,434 474 76,0 12,2 5,2 2,1 1,3 0,5 Comparison Example 2 0,182 0,394 474 58,0 8,7 27,2 11,9 9,8 10 Comparison Example 3 0,223 0,451 506 86,0 11,6 3,6 1,4 1,0 0,2 Comparison Example 4 0,184 0,395 474 58,0 8,3 24,6 10,7 9,3 6 Comparison Example 5 0,178 0,389 474 56 5,9 45,9 20,2 24,6 204

[0135] Comparative examples 1-4 used H1 as a host and / or as a blocking layer. When H1 was used as both a host and a blocking layer, the effectiveness was 2.1% for 9% doping and 1.4% for 15% doping. The lifetimes of the devices (LT 80 ) of 2000 cd / m² 2 The operating times were 0.5 hours and 0.2 hours, respectively. Minor improvements were achieved using H2 as the BL. However, the lifespan of the devices still did not exceed 10 hours from an initial brightness of 2000 cd / m². 3 .

[0136] As can be seen from apparatus examples 1-23, the connections according to the invention resulted in significantly better device efficiencies and lifetimes when used as a host. Apparatus example 10, for instance, showed a lifetime of 350 hours when connection 3 was used as the host.

[0137] Additionally, the compounds according to the invention can also be used with azadibenzothiophene or azadibenzofuran as a blocking layer. Comparative Example 5 used H₂ as a host and a blocking layer. At 5.9 V, the device achieved 1000 cd / m². 2 with an efficiency of 20.5%. The lifetime was 204 hours. As shown in device example 19, which used compound 4 as the blocking layer, the device achieved 1000 cd / m². 2 At 5.6 V, an efficiency of 19.8% was achieved. The lifetime was 230 hours. Device Example 19 demonstrated a lower operating voltage than the corresponding Comparative Example 5 and maintained comparable device efficiency. Furthermore, Device Example 19 demonstrated an improved operating lifetime compared to Comparative Example 5, providing a lifetime of 204 hours compared to 230 hours.

[0138] It is understood that the various embodiments described herein are merely exemplary and are not intended to limit the scope of the invention.

Claims

[1] A compound comprising a bicarbazole, the compound having the following formula: where R a and R d can represent mono-, di-, tri- or tetrasubstitutions and R b and R c can represent mono-, di-, or trisubstitutions; where R a , R b , R c , R d , R1 and R2 are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl: where only one of R1 and R2 has the following formula: where A and B are independently 5- or 6-membered carbocyclic or heterocyclic rings; where R A and R B are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl; where X is S, O or Se. [2] A compound according to claim 1, wherein R1 and R2 are each independently selected from aryl and heteroaryl. [3] A compound according to claim 1, wherein at least one of R1 and R2 has the following formula: where R A and R B can represent mono-, di-, tri- or tetrasubstitutions; where R A and R B are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl; and where Y1, Y2, Y3, Y4, Y5, Y6, Y7 and Y8 are independently selected from nitrogen and carbon. [4] A compound according to claim 1, wherein A and B are each independently selected from phenyl and pyridine. [5] A compound according to claim 1, wherein the compound has the following formula: where R A and R Bcan represent mono-, di-, tri- or tetrasubstitutions; where R A and R B are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, aryl and heteroaryl; and where Y1, Y2, Y3, Y4, Y5, Y6, Y7 and Y8 are each independently selected from nitrogen and carbon. [6] A compound according to claim 1, wherein the compound is selected from the group consisting of: [7] A first device comprising an organic light-emitting device, further comprising: an anode; a cathode; and an organic layer disposed between the anode and the cathode, the organic layer comprising a compound according to any one of the preceding claims. [8] The first device according to claim 7, wherein the organic layer is a blocking layer and the compound of formula I is a blocking material. [9] The first device of claim 7, wherein the organic layer is an emitter layer and the compound of formula I is a host. [10] The first device of claim 9, wherein the emitter layer further comprises a phosphorescent emitter dopant of the following formula: [11] The first device according to any one of claims 7 to 10, wherein the first device is a consumer product. [12] The first device according to any one of claims 7 to 10, wherein the first device is an organic light emitting device.

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