Metal complex, organic electroluminescent element and consumer product

Abstract

The present invention relates to a metal complex, an organic electroluminescent element and a consumer product. The metal complex of the present invention is used as a luminescent material to obtain a red phosphorescent material with high luminescent efficiency, and the prepared luminescent material has good thermal stability. The organic electroluminescent element prepared by the present invention emits red phosphorescence and has the advantages of a narrow emission spectrum, high stability and high efficiency. The electronic device of the present invention contains the organic electroluminescent element of the present invention, so as to obtain a consumer product with red electroluminescence and improved luminescent efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of luminescent materials, and in particular relates to a metal complex, an organic electroluminescent element and a consumer product. Background Art

[0002] Currently, optoelectronic devices using organic materials are becoming more and more popular, and many materials used to make the devices are relatively cheap, so organic optoelectronic devices have the potential to have cost advantages over inorganic devices. In addition, the inherent properties of organic materials (such as their flexibility) can make them more suitable for specific applications, such as manufacturing on flexible substrates. Examples of organic optoelectronic devices include organic light emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can have performance advantages over conventional materials.

[0003] OLEDs utilize organic thin films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly attractive technology for use in applications such as flat panel displays, lighting, and backlighting.

[0004] One application of phosphorescent emitting molecules is full-color displays. Industry standards for such displays require pixels that are suitable for emitting specific colors. Specifically, these standards require saturated red, green, and blue pixels. Alternatively, OLEDs can be designed to emit white light. In conventional liquid crystal displays, an absorption filter is used to filter the emission from a white backlight to produce red, green, and blue emissions. The same technology can also be used for OLEDs. White OLEDs can be single-emission layer (EML) devices or stacked structures. Color can be measured using CIE coordinates well known in the art. The luminescent materials in the prior art have poor luminescent stability and low luminous efficiency.

[0005] In view of the above reasons, the present invention is proposed. Summary of the invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides a metal complex, an organic electroluminescent element and a consumer product. When the metal complex of the present invention is used in OLED, especially in the green to red emission region, it exhibits enhanced phosphorescence quantum yield.

[0007] The first purpose of the present invention is to provide a metal complex with stable electroluminescence and high luminescence efficiency.

[0008] The second object of the present invention is to provide an organic electroluminescent element made of the metal complex.

[0009] The third object of the present invention is to provide a consumer product made of the organic electroluminescent element.

[0010] In order to achieve the above object, the present invention adopts the following technical solution:

[0011] A metal complex, the metal complex comprising a ligand LA of formula I, wherein the structure of formula I is as follows:

[0012]

[0013] Among them, W 1 , W 2 , W 3 , W 4 Each independently selected from N or CR 1 , or W 1 and W 2 , W 2 and W 3 , W 3 and W 4 Each represents a group represented by the following formula (II), formula (III), formula (IV) or formula (V), and at least one group is one of the groups represented by formula (II) to formula (III);

[0014]

[0015] Each z represents CR independently 3 or N, and two adjacent "^" refer to adjacent groups W in formula (I) 1 and W 2 , W 2 and W 3 , W 3 and W 4 ;

[0016] X 1 ~X 6 Each independently selected from N or CR 4 ;

[0017] R 1 , R 2 , R 3 , R 4 is selected, identically or differently at each occurrence, from hydrogen, deuterium, fluorine, C 1 ~C 40 Alkyl, C 3 ~C 40 Cycloalkyl, C 1 ~C 40 Heteroalkyl, C 3 ~C 40 Heterocycloalkyl, C 6 ~C 60 Aralkyl, C 1 ~C 40 Alkoxy, C6 ~C 60 Aryloxy, amino, C 3 ~C 40 Silane, C 2 ~C 40 Alkenyl, C 5 ~C 40 Cycloalkenyl, C 3 ~C 40 Heteroalkenyl, C 2 ~C 40 Alkynyl, C 6 ~C 60 Aryl, C 2 ~C 60 Heteroaryl, C 1 ~C 40 The group consisting of acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfenyl, sulfinyl, sulfonyl and phosphino; and any two or more adjacent substituents are optionally joined or fused together to form a substituted or unsubstituted five-membered ring, six-membered ring or polycyclic ring;

[0018] The ligand LA is coordinated by the metal M to form a five-membered chelate ring;

[0019] wherein the ligand LA can be linked to other ligands to form a tridentate, tetradentate, pentadentate or hexadentate ligand;

[0020] The M is selected from one of Os, Ir, Pd, Pt, Cu, Ag and Au. Preferably, M is selected from one of Ir, Pd or Pt.

[0021] Further, the ligand LA is selected from the group consisting of:

[0022]

[0023]

[0024]

[0025] R 1 ~R 7 At each occurrence, identically or differently selected from hydrogen, deuterium, fluorine, C 1 ~C 40 Alkyl, C 3 ~C 40 Cycloalkyl, C 1 ~C 40 Heteroalkyl, C 3 ~C 40 Heterocycloalkyl, C 3 ~C 40 Silane, C 6 ~C 60 Aryl, C2 ~C 60 The group consisting of heteroaryl and nitrile.

[0026] Preferably, the R 1 ~R 7 At each occurrence, each is independently selected from hydrogen, deuterium, fluorine, nitrile, R A1 ~R A55 , R B1 ~R B45 , R C1 ~R C295 Groups formed;

[0027] Among them, R A1 ~R A55 The structural formula is as follows:

[0028]

[0029] R B1 ~R B45 The structural formula is as follows:

[0030]

[0031] R C1 ~R C295 The structural formula is as follows:

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040] Furthermore, the metal complex has the formula Ir(LA) 2 (LC), wherein LA and LC are different from each other. The LC is:

[0041]

[0042] Among them, R, R a , R b , R c , Rd , R e , R f Each independently selected from hydrogen, deuterium, fluorine, nitrile, C 1 ~C 40 Alkyl, C 3 ~C 40 Cycloalkyl, C 1 ~C 40 Heteroalkyl, C 3 ~C 40 Heterocycloalkyl, C 3 ~C 40 Silane, C 6 ~C 60 Aryl, C 2 ~C 60 Any two or more adjacent substituents are optionally joined or fused to form a substituted or unsubstituted five-membered ring, six-membered ring or polycyclic ring.

[0043] Preferably, the LC is selected from the group consisting of structures shown by LC1 to LC60, and the specific structures of LC1 to LC60 are as follows:

[0044]

[0045]

[0046] Regarding the oxidation state of the metal M, when M is Ir, the oxidation valence state of Ir may be 3, and when M is Pt, the oxidation valence state of Pt may be 2.

[0047] "Halo", "halogen", "halogen atom", "halo" in the sense of the present invention are used interchangeably and refer to fluorine, chlorine, bromine or iodine.

[0048] "Acyl" within the meaning of the present invention refers to a substituted carbonyl (COR).

[0049] "Ester" in the sense of the present invention refers to a substituted oxycarbonyl (-OCOR or CO 2 R).

[0050] An "ether" within the meaning of the present invention is an -OR group.

[0051]

[0013] As used herein, "thio" or "thioether" are used interchangeably and refer to a -SR group.

[0052] "Sulfinyl" within the meaning of this invention is a -SOR group.

[0053] The term "sulfonyl" as used herein refers to -SO 2 R group.

[0054] The "phosphino" group in the sense of the present invention refers to -PR 3 A group wherein each R may be the same or different.

[0055] The "silyl group" in the sense of the present invention refers to -SiR 3 A group wherein each R may be the same or different.

[0056] Each of the above R is preferably selected from the group consisting of alkyl, cycloalkyl, aryl and heteroaryl.

[0057] “Alkyl”, “alkenyl” or “alkynyl” in the sense of the present invention is preferably taken to mean methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, cyclopentyl, n-hexyl, neohexyl, cyclohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or octynyl.

[0058] “Alkoxy” in the sense of the present invention is taken to mean, preferably, alkoxy having 1 to 40 carbon atoms, methoxy, trifluoromethoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, sec-pentoxy, 2-methylbutoxy, n-hexyloxy, cyclohexyloxy, n-heptyloxy, cycloheptyloxy, n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy and 2,2,2-trifluoroethoxy.

[0059] Generally speaking, "cycloalkyl" and "cycloalkenyl" according to the present invention refer to and include monocyclic, polycyclic and spiroalkyl groups. Preferred cycloalkyl groups are cycloalkyl groups containing 3 to 15 ring carbon atoms, which may be cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptyl, cycloheptenyl, bicyclo[3.1.1]heptyl, spiro[4.5]decyl, spiro[5.5]undecyl, adamantyl, etc., wherein one or more -CH 2 - group may be replaced by the above-mentioned groups; in addition, one or more hydrogen atoms may be replaced by a deuterium atom, a halogen atom or a nitrile group.

[0060] In the sense of the present invention, "heteroalkyl" or "heterocycloalkyl" refers to an alkyl or cycloalkyl group, preferably an alkyl or cycloalkyl group having 1 to 40 carbon atoms, in which a single hydrogen atom or -CH 2 - a group which may be substituted by oxygen, sulfur, a halogen atom, nitrogen, phosphorus, boron, silicon or selenium, preferably a group which is substituted by oxygen, sulfur or nitrogen. In addition, the heteroalkyl group or heterocycloalkyl group may be optionally substituted.

[0061] "Heteroalkenyl" or "heterocycloalkenyl" in the sense of the present invention refers to an alkenyl or cycloalkenyl group in which at least one carbon atom is replaced by a heteroatom. Optionally, the at least one heteroatom is selected from oxygen, sulfur, nitrogen, phosphorus, boron, silicon or selenium, preferably oxygen, sulfur or nitrogen. Preferred alkenyl and cycloalkenyl groups are those containing 3 to 15 carbon atoms. In addition, the heteroalkenyl and heterocycloalkenyl groups may be optionally substituted.

[0062] "Aralkyl" or "arylalkyl" within the meaning of the present invention are used interchangeably and refer to an alkyl group substituted by an aryl group. Additionally, the aralkyl group may be optionally substituted.

[0063] "Aryl" according to the present invention refers to and includes monocyclic aromatic hydrocarbon groups and polycyclic aromatic ring systems. Polycyclic rings may have two or more rings in which two carbons are shared by two adjacent rings (the rings are "fused"), wherein at least one of the rings is an aromatic hydrocarbon group, for example, the other rings may be cycloalkyl, cycloalkenyl, aryl, heterocyclic and / or heteroaryl. Preferred aryl groups are those containing 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Particularly preferred are aryl groups having six carbons, ten carbons or twelve carbons. Suitable aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenanthrene, fluorene, pyrene, perylene, and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. In addition, the aryl group may be optionally substituted.

[0064] "Heteroaryl" in the sense of the present invention refers to and includes monocyclic aromatic groups and polycyclic aromatic ring systems that include at least one heteroatom. Heteroatoms include, but are not limited to, oxygen, sulfur, nitrogen, phosphorus, boron, silicon or selenium. In many cases, oxygen, sulfur or nitrogen are preferred heteroatoms. Monocyclic heteroaromatic systems are preferably monocyclic rings with 5 or 6 ring atoms, and the rings may have one to six heteroatoms. Heteropolycyclic ring systems may have two or more rings in which two atoms are common to two adjacent rings (the rings are "fused"), wherein at least one of the rings is a heteroaryl, for example, the other rings may be cycloalkyl, cycloalkenyl, aryl, heterocycle and / or heteroaryl. Heteropolycyclic aromatic ring systems may have one to six heteroatoms on each ring of the polycyclic aromatic ring system. Preferred heteroaryls are heteroaryls containing three to thirty carbon atoms, preferably three to twenty carbon atoms, and more preferably three to twelve carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridyl indole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazole In some embodiments, the heteroaryl group may be substituted with 1,2-azaborane, 1,3-azaborane, 1,4-azaborane, borazine and aza analogs thereof. In some embodiments, the heteroaryl group may be substituted with 1,2-azaborane, 1,3-azaborane, 1,4-azaborane, borazine and aza analogs thereof. In some embodiments, the heteroaryl group may be substituted with 1,2-azaborane, 1,3-azaborane, 1,4-azaborane, borazine and aza analogs thereof. In some embodiments, the heteroaryl group may be substituted with 1,2-azaborane, 1,3-azaborane, 1,4-azaborane, borazine and aza analogs thereof.

[0065] In many cases, the substituent is selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, aralkyl, alkoxy, aryloxy, amino, silanyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, and phosphino.

[0066] As used herein, "combinations thereof" or "groups" means that one or more members of the applicable list are combined to form known or chemically stable arrangements that can be envisioned by one of ordinary skill in the art from the applicable list. For example, alkyl and deuterium can be combined to form partially or fully deuterated alkyl; halogen and alkyl can be combined to form haloalkyl substituents, such as trifluoromethyl, etc.; and halogen, alkyl and aryl can be combined to form haloaralkyl.

[0067] In one example, the term substituted includes combinations of two to four of the listed groups.

[0068] In another example, the term substitution includes a combination of two to three groups. In yet another example, the term substitution includes a combination of two groups. The preferred combination of substituents is a combination containing up to fifty atoms that are not hydrogen or deuterium, or a combination including up to forty atoms that are not hydrogen or deuterium, or a combination including up to thirty atoms that are not hydrogen or deuterium. In many cases, the preferred combination of substituents will include up to twenty atoms that are not hydrogen or deuterium.

[0069] Furthermore, the ligand LA includes one of LA1 to LA360, and the specific structures of LA1 to LA360 are as follows:

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083] Furthermore, the metal complex is selected from Ir(LAi) 2 (LCj), wherein i is an integer from 1 to 360, and j is an integer from 1 to 60; LA1 to LA360 are the structures shown above, and LC1 to LC60 are the structures shown above.

[0084] Furthermore, the metal complex Ir(LAi) 2 (LCj) is preferably selected from the group consisting of the following structures:

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092] The organic electroluminescent material of the present invention includes one or more of the metal complexes of the present invention. The organic electroluminescent material of the present invention may be formed only of one or more of the metal complexes of the present invention, or may contain other materials in addition to the metal complex of the present invention.

[0093] By including the metal complex of the present invention in the organic electroluminescent material of the present invention, an organic electroluminescent material with red electroluminescence and high luminescence efficiency can be obtained. In addition, the organic electroluminescent material of the present invention is an organic electroluminescent material with good thermal stability.

[0094] An organic electroluminescent element comprises a first electrode, a second electrode and an organic layer arranged between the first electrode and the second electrode, wherein the organic layer comprises the metal complex.

[0095] Furthermore, the organic layer also includes a main material, and the main material includes the following chemical groups: a group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, nitrogen triphenylene, azacarbazole, azadibenzothiophene, azadibenzofuran and azadibenzoselenophene.

[0096] wherein any substituents in the subject are each independently selected from the group consisting of non-fused substituents: C m H 2m+1 , OC m H 2m+1 ,OAr 1 、N(C m H 2m+1 ) 2 、N(Ar 1 )(Ar 2 ), CH=CH-C m H 2m+1 、C≡CC m H 2m+1 ,Ar1 ,Ar 1 -Ar 2 , C m H 2m -Ar 1 or no substituent, wherein m is an integer from 1 to 10; and wherein Ar 1 with Ar 2 Independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole and heteroaromatic analogs thereof.

[0097] In the organic electroluminescent device of the present invention, one layer may be a layer containing the metal complex of the present invention, or two or more layers may contain the metal complex of the present invention.

[0098] The organic layer may be an emissive layer and the metal complex as described herein may be an emissive dopant or a non-emissive dopant.

[0099] A consumer product made from the organic electroluminescent element.

[0100] The consumer product described in the present invention can be one of the following products: flat panel displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior lighting and / or signaling, heads-up displays, fully or partially transparent displays, flexible displays, laser printers, telephones, cellular phones, tablet computers, tablet phones, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, video cameras, viewfinders, microdisplays with a diagonal of less than 2 inches, 3-D displays, virtual reality or augmented reality displays, vehicles, video walls comprising multiple displays tiled together, theater or stadium screens, light therapy devices and signage.

[0101] Compared with the prior art, the present invention has the following beneficial effects:

[0102] The metal complex of the present invention effectively prevents the free rotation of the bond from causing energy loss and improves quantum efficiency by introducing pyrrole, pyrazole or imidazole into the pyridine ring to form a large conjugated rigid structure ligand. It not only has good thermal stability, but also has an increased conjugated area, improved molecular film formation and exciton transmission performance, and a reduced material sublimation temperature. It can be used as a luminescent material to obtain green, orange, or red phosphorescent materials with high luminous efficiency. The electronic device of the present invention can obtain a consumer product with a narrow emission spectrum, high stability and high efficiency by containing the organic electroluminescent element of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0103] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0104] Figure 1 A schematic diagram of an organic light-emitting device 100 is shown. The illustration is not necessarily drawn to scale. The device 100 may include a substrate 101, an anode 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light-emitting layer 106, an electron transport layer 107, an electron injection layer 108, a cathode 109, and a capping layer (CPL) 110. The device 100 may be manufactured by depositing the described layers in order.

[0105] Figure 2 Schematic diagram of an organic light-emitting device 200 showing two light-emitting layers. The device includes a substrate 201, an anode 202, a hole injection 203, a hole transport layer 204, a first light-emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light-emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode 213. The device 200 can be prepared by depositing the layers described in sequence. Because the most common OLED device has one light-emitting layer, and the device 200 has a first light-emitting layer and a second light-emitting layer, the light emission peaks of the first light-emitting layer and the second light-emitting layer can be overlapping, cross-overlapping, or non-overlapping. In the corresponding layers of the device 200, materials similar to those described with respect to the device 1 can be used. Figure 2 One example is provided of how some layers may be added from the structure of device 100 . DETAILED DESCRIPTION

[0106] In the organic electroluminescent device of the present invention, the composition of the layers other than the layer containing the metal complex of the present invention is not limited at all, and those skilled in the art can determine the composition of other layers of the organic electroluminescent device as needed based on the common technical knowledge in the field.

[0107] Generally speaking, an OLED includes at least one organic layer disposed between and electrically connected to an anode and a cathode. Figure 1 A schematic diagram of an organic light-emitting device 100 is shown. The illustration is not necessarily drawn to scale. The device 100 may include a substrate 101, an anode 102, a hole injection layer 103, a hole transport layer 104, an electron blocking layer 105, a light-emitting layer 106, an electron transport layer 107, an electron injection layer 108, a cathode 109, and a capping layer (CPL) 110. The device 100 may be manufactured by depositing the described layers in order.

[0108] Figure 2 A schematic diagram of an organic light-emitting device 200 containing two light-emitting layers is shown. The device includes a substrate 201, an anode 202, a hole injection layer 203, a hole transport layer 204, a first light-emitting layer 205, an electron transport layer 206, a charge generation layer 207, a hole injection layer 208, a hole transport layer 209, a second light-emitting layer 210, an electron transport layer 211, an electron injection layer 212, and a cathode 213. The device 200 can be prepared by depositing the layers described in sequence. Because the most common OLED device has a single-color light-emitting layer or a light-emitting layer having three primary colors, the device 200 has two light-emitting layers of the same light color. In the corresponding layers of the device 200, materials similar to those described with respect to the device 100 can be used. Figure 2 One example is provided of how some layers may be added from the structure of device 100 .

[0109] Figure 1 and Figure 2 The simple layered structure illustrated in is provided as a non-limiting example, and it should be understood that embodiments of the present invention can be used in conjunction with a variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures can be used. Functional OLEDs can be achieved by combining the various layers described in different ways, or several layers can be omitted entirely, based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials different from those specifically described may be used. Although many of the examples provided herein describe various layers as including a single material, it will be understood that combinations of materials, such as a mixture of a matrix and a dopant, or more generally, a mixture, can be used. Also, the layers may have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 204 transports holes and injects holes into light-emitting layer 205, and may be described as a hole transport layer or an electron blocking layer. In one embodiment, the OLED may be described as having an organic layer disposed between a cathode and an anode. This organic layer may include a single layer or may further include, for example Figure 1 and Figure 2 Multiple layers of different organic materials are described.

[0110] Structures and materials not specifically described may also be used, such as PLEDs comprising polymer materials. As another example, an OLED having a single organic layer or multiple stacks may be used. The OLED structure may be separated from Figure 1 and Figure 2 For example, the substrate may include angled reflective surfaces to improve light coupling.

[0111] Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, organic vapor deposition methods, or applying one or more layers with the aid of carrier gas sublimation, wherein the deposition temperature is between 10 and 20 °C. 5 The material is applied at a pressure between 100 mbar and 1 bar. A particular example of this method is an organic vapor jet printing method, in which the material is applied directly through a nozzle and is therefore structured. Other suitable deposition methods include, for example, producing one or more layers by spin coating, or by means of any desired printing method such as screen printing, flexographic printing, lithography, photoinduced thermography, thermal transfer, inkjet printing or nozzle printing. Soluble compounds, for example, are obtained by appropriate substitution. These methods are also particularly suitable for oligomers, dendrimers and polymers. In addition, hybrid methods are feasible, in which, for example, one or more layers are applied from a solution and one or more additional layers are applied by vapor deposition.

[0112] The device manufactured according to the embodiment of the present invention may further optionally include a barrier layer. One purpose of the barrier layer is to protect the electrode and the organic layer from being damaged by exposure to harmful substances in the environment, including moisture, vapor and / or gas, etc. The barrier layer may be deposited on the substrate, the electrode, under the substrate, the electrode, or next to the substrate, the electrode, or on any other part of the device, including the edge. The barrier layer may include a single layer or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may include a composition having a single phase and a composition having multiple phases. Any suitable material or material combination may be used for the barrier layer. The barrier layer may be incorporated into an inorganic or organic compound or both. Preferably, the barrier layer includes a mixture of a polymeric material and a non-polymeric material. In order to be regarded as a mixture, the aforementioned polymer and non-polymeric materials constituting the barrier layer should be deposited under the same conditions and / or at the same time. The weight ratio of the polymeric material to the non-polymeric material may be in the range of 95 / 5 to 5 / 95. In one example, the mixture of the polymeric material and the non-polymeric material is essentially composed of polymeric silicon and inorganic silicon.

[0113] In any of the above-mentioned compounds used in each layer of the above-mentioned OLED device, the hydrogen atoms may be partially or fully deuterated. Thus, any specific listed substituents, such as (but not limited to) methyl, phenyl, pyridyl, etc., may be in their non-deuterated, partially deuterated, and fully deuterated forms. Similarly, substituent classes (such as (but not limited to) alkyl, aryl, cycloalkyl, heteroaryl, etc.) may also be in their non-deuterated, partially deuterated, and fully deuterated forms.

[0114] The materials and structures described herein can be applied to devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors can use the materials and structures. Further, organic devices such as organic transistors can use the materials and structures.

[0115] These processes are generally known to those skilled in the art and they can apply them without inventive step to organic electroluminescent devices comprising the compounds according to the invention.

[0116] According to one embodiment, novel ligands for metal complexes are disclosed. The inventors have discovered that the introduction of these ligands unexpectedly narrows the emission spectrum, lowers the sublimation temperature, and improves the luminescence efficiency of the device.

[0117] As the preparation method of the organic electroluminescent element of the present invention, the following preparation method can be listed, but it is not limited thereto, and those skilled in the art can make various changes according to the technical common sense in the field. The above-mentioned preparation method includes the following steps:

[0118] Cleaning process: Use cleaning agent, deionized water, organic solvent, etc. to clean the glass substrate with ITO;

[0119] A step of forming a hole injection layer: depositing a hole injection layer forming material containing the metal complex of the present invention on the aforementioned anode layer by vacuum deposition, thereby forming a hole injection layer containing the metal complex of the present invention on the aforementioned substrate;

[0120] A step of forming a hole transport layer: forming a hole transport layer on the hole injection layer by vacuum evaporation;

[0121] A step of forming an organic light-emitting layer: vacuum evaporating an organic light-emitting layer-forming material containing the material of the present invention on the aforementioned hole transport layer to form an organic light-emitting layer containing the metal complex of the present invention on the aforementioned hole transport layer;

[0122] A step of forming an electron transport layer: vacuum evaporating an electron transport layer forming material containing the metal complex of the present invention on the organic light-emitting layer, thereby forming an electron transport layer containing the metal complex of the present invention on the organic light-emitting layer;

[0123] Step of forming a cathode layer: forming a cathode layer by evaporating, sputtering or spin coating a cathode forming material on the electron transport layer.

[0124] In the embodiments of the present invention, the performance testing conditions of the prepared electroluminescent device are as follows:

[0125] Brightness and chromaticity coordinates: tested using a spectral scanner PhotoResearch PR-715;

[0126] Current density and lighting voltage: tested using Keithley 2420 digital source meter;

[0127] Power efficiency: tested using NEWPORT 1931-C;

[0128] Life test: Use LTS-1004AC life test device.

[0129] Example

[0130] The invention also discloses a method for preparing the metal complex Ir(LAi) 2 The general synthesis method of (LCj) comprises the following steps:

[0131] Step 1: Preparation of iridium chloride coordination intermediate

[0132]

[0133] 10.0 mmol of compound LAi and 5.0 mmol of IrCl 3 ·3H 2 O was dispersed in 30 mL of ethylene glycol ethyl ether and 10 mL of water, and the temperature was raised to reflux for reaction for 24 hours under nitrogen protection, and the mixture was cooled to room temperature, filtered, and the filter cake was washed with water and dried in vacuo to obtain an iridium chloride coordination intermediate, which was directly used in the next step of preparation without purification.

[0134] Step 2: Preparation of metal complex Ir(LAi) 2 (LCj)

[0135]

[0136] 5.0mmol of iridium chloride coordination intermediate, 15.0mmol of LCj and 25.0mmol of anhydrous potassium carbonate or anhydrous sodium carbonate are dispersed in 40mL of acetonitrile and 40mL of chloroform. Under nitrogen protection, the temperature is raised and refluxed for reaction for 24 hours. The reaction solution is cooled to room temperature, poured into water, extracted with dichloromethane, the organic phase is dried, filtered, and the filtrate is concentrated under reduced pressure. The residue is separated and purified by silica gel column to obtain compound Ir(LAi): 2 (LCj).

[0137] Wherein, i is an integer from 1 to 360, and j is an integer from 1 to 60.

[0138] Example 1

[0139] The following uses ligands LA50 and LC4 as representative examples to prepare metal complex PT83, and further describes in detail that the preparation of the metal complex of the present invention includes the following steps:

[0140] Step 1: Preparation of compound Int-1

[0141]

[0142] 20.0 mmol of SM-0 (CAS: 935753-84-7) was dissolved in 50 mL of phosphorus oxychloride. Under nitrogen protection, the mixture was heated to reflux with stirring for 5 hours, cooled to room temperature, concentrated under reduced pressure, added with 250 mL of ice-water solution, stirred for 30 minutes, filtered, and the filter cake was washed with water. The compound Int-1 was obtained as a yellow solid with a yield of 87%.

[0143] Step 2: Preparation of compound Int-2

[0144]

[0145] 20.0 mmol of Int-1 and 24.0 mmol of 3,5-dimethylphenylboronic acid were dissolved in 50 mL of toluene. Under nitrogen protection, 40.0 mmol of potassium carbonate and 1.0 mmol of Pd(PPh 3 ) 4 and 2.0 mmol of potassium iodide, then add 30 mL of ethanol and 25 mL of water, raise the temperature to reflux, stir the reaction for 12 hours, cool to room temperature, add 50 mL of water, extract with ethyl acetate, separate the organic phase, wash three times with saturated brine, collect the organic phase, dry it, filter, concentrate it under reduced pressure, and purify it with a silica gel column to obtain compound Int-2 as a yellow solid with a yield of 82%.

[0146] Step 3: Preparation of compound LA50

[0147]

[0148] Under nitrogen protection, 20.0 mmol of Int-2 and 22.0 mmol of iodobenzene were dissolved in 80 mL of toluene, and 30.0 mmol of sodium tert-butoxide and 0.1 mmol of Pd 2 (dba) 3 and 0.2 mmol of Xantphos, heat to reflux and stir to react for 12 hours, cool to room temperature, add 50 mL of water, extract with ethyl acetate, separate the organic phase, wash three times with saturated brine, collect the organic phase, dry it, filter it, concentrate the filtrate under reduced pressure, and separate and purify it with a silica gel column to obtain compound LA50 as a yellow solid with a yield of 85%.

[0149] Step 4: Preparation of iridium chloride coordination intermediate

[0150]

[0151] 10.0 mmol of compound LA50 and 5.0 mmol of IrCl 3 ·3H 2 O was dispersed in 30 mL of ethylene glycol ethyl ether and 10 mL of water, and refluxed under nitrogen protection for 24 hours. The mixture was cooled to room temperature, filtered, and the filter cake was washed with water and dried in vacuo to obtain an iridium chloride coordination intermediate as a red solid, which was directly used in the next step of preparation without purification.

[0152] Step 5: Preparation of metal complex PT83

[0153]

[0154] 5.0mmol of iridium chloride coordination intermediate, 15.0mmol of LC4 and 25.0mmol of anhydrous sodium carbonate were dispersed in 40mL of acetonitrile and 40mL of chloroform. Under nitrogen protection, the temperature was raised and refluxed for reaction for 24 hours. The mixture was cooled to room temperature, poured into water, extracted with dichloromethane, the organic phase was dried, filtered, and the filtrate was concentrated under reduced pressure. The residue was separated and purified by silica gel column to obtain compound PT83 as a red solid. The yield was 35%. MS (MALDI-TOF): m / z 1099.4502 [M+H] + .

[0155] Example 2

[0156] The following ligands LA12 and LC11 are used as representative examples to prepare the metal complex Ir(LA12): 2 (LC11), further detailed description, the preparation of the metal complex of the present invention comprises the following steps:

[0157] Step 1: Preparation of iridium chloride coordination intermediate

[0158]

[0159] 10.0 mmol of compound LA12 (prepared according to the synthesis method of Tetrahedron, 60, 933-938) and 5.0 mmol of IrCl 3 ·3H 2 O was dispersed in 30 mL of ethylene glycol ethyl ether and 10 mL of water, and refluxed under nitrogen protection for 24 hours. The mixture was cooled to room temperature, filtered, and the filter cake was washed with water and dried in vacuo to obtain an iridium chloride coordination intermediate as a red solid, which was directly used in the next step of preparation without purification.

[0160] Step 2: Preparation of metal complex Ir(LA12) 2 (LC11)

[0161]

[0162] 5.0mmol of iridium chloride coordination intermediate, 15.0mmol of LC11 and 25.0mmol of anhydrous sodium carbonate were dispersed in 40mL of acetonitrile and 40mL of chloroform. Under nitrogen protection, the temperature was raised and refluxed for 24 hours. The reaction solution was cooled to room temperature, poured into water, extracted with dichloromethane, the organic phase was dried, filtered, and the filtrate was concentrated under reduced pressure. The residue was separated and purified by silica gel column to obtain compound Ir (LA12) 2 (LC11), red solid; yield 33%, MS (MALDI-TOF): m / z 1043.4563 [M+H] + .

[0163] Example 3

[0164] The preparation of the metal complex PT177 comprises the following steps:

[0165] Step 1: Preparation of compound Int-3

[0166]

[0167] Under nitrogen protection, 20.0 mmol of 2-chloro-3-hydrazinopyridine (CAS: 117087-45-3) and 24.0 mmol of 3-methylbutanal were dissolved in 80 mL of 4% dilute sulfuric acid aqueous solution, the temperature was raised and refluxed with stirring to react for 24 hours, then cooled to room temperature, extracted with toluene, the organic phase was washed with water, dried, filtered, and the filtrate was concentrated to dryness under reduced pressure, separated and purified by silica gel column to obtain compound Int-3 with a yield of 47%.

[0168] Step 2: Preparation of compound Int-4

[0169]

[0170] 20.0 mmol of Int-3 and 24.0 mmol of (2′-chloro-[1,1′-biphenyl]-2-yl)boronic acid were dissolved in 50 mL of toluene. Under nitrogen protection, 40.0 mmol of potassium carbonate and 1.0 mmol of Pd(PPh 3 ) 4 , 30 mL of ethanol and 25 mL of water, heat to reflux, stir and react for 12 hours, cool to room temperature, add 50 mL of water, extract with ethyl acetate, collect the organic phase, dry it, filter, concentrate under reduced pressure, and separate and purify it with a silica gel column to obtain compound Int-4 as a yellow solid with a yield of 72%.

[0171] Step 3: Preparation of compound Int-5

[0172]

[0173] Under nitrogen protection, 20.0 mmol of Int-4 was dissolved in 80 mL of toluene, and 30.0 mmol of sodium tert-butoxide, 0.1 mmol of Pd 2 (dba) 3 and 0.4 mmol of 10% tri-tert-butylphosphonium toluene solution, heat to 100°C and stir to react for 12 hours, cool to room temperature, add 50 mL of water, extract with toluene, collect the organic phase, dry it, filter it, concentrate the filtrate under reduced pressure, and separate and purify it with a silica gel column to obtain compound Int-5 as a yellow solid with a yield of 86%.

[0174] Step 4: Preparation of iridium chloride coordination intermediate

[0175]

[0176] 10.0 mmol of compound Int-5 and 5.0 mmol of IrCl 3 ·3H 2 O was dispersed in 30 mL of ethylene glycol ethyl ether and 10 mL of water, and refluxed under nitrogen protection for 24 hours. The mixture was cooled to room temperature, filtered, and the filter cake was washed with water and dried in vacuo to obtain an iridium chloride coordination intermediate as a red solid, which was directly used in the next step of preparation without purification.

[0177] Step 5: Preparation of metal complex PT177

[0178]

[0179] 5.0 mmol of iridium chloride coordination intermediate, 15.0 mmol of LC4 and 25.0 mmol of anhydrous potassium carbonate were dispersed in 40 mL of acetonitrile and 40 mL of chloroform. Under nitrogen protection, the temperature was raised and refluxed for reaction for 24 hours. The mixture was cooled to room temperature, poured into water, extracted with dichloromethane, the organic phase was dried, filtered, and the filtrate was concentrated under reduced pressure. The residue was separated and purified by silica gel column to obtain compound PT177 as a red solid. The yield was 47%. MS (MALDI-TOF): m / z 1023.3328 [M+H] + .

[0180] Referring to the synthesis method of the above embodiment, only the ligand LC4 was used as the representative LCj to prepare the metal complexes: PT01~PT82, PT84~PT176, PT178~PT188.

[0181] Example 4 Preparation of organic electroluminescent element

[0182] The glass substrate coated with the ITO conductive layer was ultrasonically treated in a cleaning agent for 30 minutes, rinsed in deionized water, ultrasonically treated in an acetone / ethanol mixed solvent for 30 minutes, baked in a clean environment until completely dry, irradiated with a UV cleaner for 10 minutes, and bombarded with a low-energy cation beam.

[0183] Place the treated ITO glass substrate in a vacuum chamber and evacuate the chamber to a vacuum level less than 1×10 -5 Pa, a layer of metallic silver is evaporated on the above ITO film as the anode layer, and the evaporated film thickness is Continue to evaporate compounds HI02 and F4TCNQ as hole injection layers, where F4TCNQ is 3% of the mass of HI02 and the evaporated film thickness is HTM is further evaporated on the hole injection layer to form a hole transport layer with a thickness of

[0184] EBM was evaporated on the hole transport layer as an electron blocking layer with a film thickness of

[0185] An organic light-emitting layer is evaporated on the aforementioned electron blocking layer. The light-emitting layer contains H1 as a main body and 3% by weight of the metal complex prepared by the present invention as a doping material. The evaporated film thickness is

[0186] A layer of LiQ and ETM is further evaporated on the organic light-emitting layer as the electron transport layer of the element, wherein LiQ is 50% of the mass of ETM and the thickness of the evaporated film is

[0187] A layer of LiF was continuously evaporated on the above-mentioned light-emitting layer as the electron injection layer of the device, and the evaporated film thickness was

[0188] On the electron injection layer, metal magnesium and silver are evaporated as the cathode layer of the element, wherein the mass ratio of magnesium to silver is 1:2 and the thickness of the evaporated film is

[0189] Finally, a layer of NPB is evaporated on the transparent cathode as the CPL layer of the component. The thickness of the evaporated film is The OLED element provided by the present invention is obtained.

[0190] The structural formulas of the aforementioned HI02, HTM, EBM, H1, LiQ, F4TCNQ, and ETM are as follows:

[0191]

[0192]

[0193] Comparative Example 1

[0194] The metal complex of the present invention in Example 4 was replaced by the compound shown in RD-1, and the other steps were the same as those in Example 4 to prepare a comparative element 1;

[0195] The structure of RD-1 is:

[0196]

[0197] Comparative Example 2

[0198] The metal complex of the present invention in Example 4 was replaced by the compound shown in RD-2, and the other steps were the same as those in Example 4 to prepare a comparative element 2;

[0199] The structure of RD-2 is:

[0200]

[0201] Comparative Example 3

[0202] The metal complex of the present invention in Example 4 was replaced by the compound shown in RD-3, and the other steps were the same as those in Example 4 to prepare a comparative element 3;

[0203] The structure of RD-3 is:

[0204]

[0205] The organic electroluminescent element prepared by the above process was subjected to the following performance tests:

[0206] The driving voltage and current efficiency of the organic electroluminescent elements prepared in Example 4 and Comparative Examples 1, 2 and 3 as well as the life of the elements were measured using a digital source meter and a brightness meter. Specifically, the voltage was increased at a rate of 0.1 V per second, and the current density of the organic electroluminescent element was measured when it reached 10 mA / cm 2 The voltage at this time is the driving voltage, and the brightness at this time is measured at the same time; the ratio of brightness to current density is the current efficiency; the LT95% life test is as follows: use a brightness meter at 1000cd / m 2 At the same brightness, the current is kept constant and the brightness decay of the organic electroluminescent element is measured to be 950cd / m 2 The time is in hours. *Data are normalized compared to Comparative Component 1.

[0207] Table 1

[0208]

[0209]

[0210]

[0211]

[0212]

[0213] As can be seen from Table 1, the metal complex of the present invention, as a doping material for the light-emitting layer, has a lower driving voltage than the comparative element, but has greater advantages in external quantum efficiency and LT95% lifespan, especially the half-width of the light-emitting peak is narrower than that of the comparative element, indicating that the metal complex of the present invention has good luminescent color purity and is a light-emitting layer doping material with excellent performance.

[0214] The difference between the compound RD-1 in Comparative Example 1 and the compound RD-2 in Comparative Example 2 and the compounds of the present invention is that the conjugation of benzothiophene is weak and the performance of metal-ligand charge migration is reduced. The ligand of the present invention forms a large conjugated plane by introducing heterocycles with strong nitrogen conjugation ability such as indole, pyrazole or imidazole, thereby avoiding energy loss caused by ligand rotation. Therefore, it has excellent performance in the luminescence performance of the element, especially the color purity and external quantum efficiency are greatly improved.

[0215] Compared with the compound of the present invention, the difference between compound RD-3 in Comparative Example 3 and the compound of the present invention is that benzindole introduces the HOMO unit of the metal complex. Although the performance of metal-ligand charge transfer is improved, the luminescent wavelength is red-shifted, and the wavelength exceeds the visible light range. The metal complex of the present invention reduces the driving voltage and improves the luminescent efficiency by increasing the conjugation level and charge transfer ability of the LUMO unit, so it performs excellently in the luminescent performance of the element.

[0216] The above Table 1 only lists the properties of some metal complexes. The inventors have also conducted the above test on other metal complexes, and the results are basically the same. Due to limited space, they are not listed one by one.

[0217] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other implementations obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A metal complex, characterized in that The metal complex has the formula Ir(LA)2(LC), and the ligand LA is selected from the group consisting of: R 1 ~R 6 at each occurrence, identically or differently selected from hydrogen, Phenyl, Groups formed; The specific structure of the LC is shown below:

2. The metal complex according to claim 1, characterized in that The ligand LA includes one of the following specific structures:

3. A metal complex, characterized in that The metal complex is selected from the group consisting of the following structures:

4. An organic electroluminescent element, comprising a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode, characterized in that: The organic layer comprises the metal complex according to any one of claims 1 to 3. 5 . A consumer product, comprising the organic electroluminescent element according to claim 4 .

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