A metal complex and its application

Abstract

The present invention relates to the field of organic electroluminescent display technology, and in particular to a metal complex and its application. The metal complex described in the present invention is a novel five-membered ring aromatic ligand, which can be used as an electrophosphorescent luminescent material. The metal complex described in the present invention electroluminesces red, has high luminous efficiency, has good thermal stability, is easy to prepare, and is easy to sublimate and purify, and has a very broad market prospect.

Description

Technical Field

[0001] The invention relates to the technical field of organic electroluminescent display, and in particular to a metal complex and application thereof. Background Art

[0002] Organic light-emitting diodes (OLEDs) use thin organic films to emit light when voltage is applied to the positive and negative terminals of the device. OLED technology is gaining more and more attention in applications such as flat-panel displays, lighting and backlighting.

[0003] One application of phosphorescent emitting molecules is full color displays, for which industry standards require pixels adapted to emit specific colors. Specifically, these standards require saturated red, green, and blue pixels, and colors can be measured using CIE coordinates, which are well known in the art.

[0004] An example of a red-emitting molecule is bis(1-phenylisoquinolinol)iridium acetylacetonate, denoted Ir(piq)2(acac), which has the following structure:

[0005]

[0006] In this and subsequent structural formulas, the coordinate bond from the metallic iridium to the nitrogen is depicted as a straight line.

[0007] At present, red phosphorescent materials still have the problems of low luminescent quantum efficiency and poor color purity. The main reason for this situation is that red light comes from the transition between energy levels with a narrow energy gap, and there are certain difficulties in the design of ligands for narrow-bandgap heavy metal complexes. Secondly, there is a strong π-π bond interaction in the system of red light materials, and the ligands have strong charge transfer characteristics, which makes more non-radiative relaxation channels exist in the narrow band gap, aggravates the quenching of phosphors, and reduces the quantum yield of the red light system. Therefore, designing and synthesizing metal complexes with excellent comprehensive performance will become an important topic in the research of organic electroluminescent materials.

[0008] In view of the above reasons, the present invention is proposed. Summary of the invention

[0009] In order to solve the above problems existing in the prior art, the present invention provides a metal complex and its application. The luminescent material prepared by using the metal complex of the present invention has good stability, and the metal complex is a red light phosphorescent material with excellent luminescent performance.

[0010] The first object of the present invention is to provide a metal complex, the molecular formula of the metal complex is: M(L A ) x (L B ) y(L C ) z ;in,

[0011] M is a metal atom with an atomic weight greater than 40;

[0012] x represents an integer of 0, 1, 2 or 3; y represents an integer of 0, 1 or 2; z represents 0 or 1; and x+y+z is equal to the oxidation state of the metal M;

[0013] L A for:

[0014] in,

[0015] X 1 , X 2 , X 3 , X 4 Each independently represents CR 0 or N;

[0016] T is selected from O, S, NR 1 , BR 1 、SiR 1 R 2 , or CR 1 R 2 , and T is CR 1 R 2 When you can 1 joined or fused to form a substituted or unsubstituted ring, containing or not containing C, N, O or S in the formed ring;

[0017] In W 1 , W 2 , W 3 , W 4 Any two adjacent groups in the formula (1) or (2) represent the following groups,

[0018]

[0019] G is selected from O, S, CR 2 R 3 NR 4 、SiR 2 R 3 or GeR 2 R 3 ; Z represents CR if they are the same or different 5 or N, and "^" indicates L A The corresponding adjacent groups W in 1 and W 2 , W 2 and W 3 or W 3 and W 4 ;

[0020] R 0 , R 1 , R 2 , R 3 , R 4 , R 5 Each is independently selected from one or more of a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, a cycloalkyl group, a heteroalkyl group, a heterocycloalkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group, an alkenyl group, a cycloalkenyl group, an isoalkenyl group, an alkynyl group, an aryl group, a heteroaryl group, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile group, an isonitrile group, a thiol group, a sulfonyl group, a sulfinyl group, a phosphine group, and a phosphinooxy group; any adjacent substituents are optionally joined or fused to form a polycyclic ring, preferably a five-membered ring or a six-membered ring;

[0021] L B for:

[0022]

[0023] Among them, R 6 , R 7 Each is independently selected from one or more of a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, a cycloalkyl group, a heteroalkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group, a silane group, an alkenyl group, a cycloalkenyl group, a heteroalkenyl group, an alkynyl group, an aryl group, a heterocyclic aryl group, an aliphatic group containing nitrogen, germanium, oxygen or sulfur, a phosphino group and a phosphinooxy group;

[0024] Ring C and ring D are each independently selected from a five-membered carbocyclic ring, a five-membered heterocyclic ring, a six-membered carbocyclic ring or a six-membered heterocyclic ring; the substituents R on ring D and ring C are 6 , R 7 is one or more than two, and R 6 , R 7 Adjacent groups in the ring are optionally joined or fused to form a five-membered ring, a six-membered ring or a polycyclic ring;

[0025] Among them, X 5 , X 6 is selected from carbon or nitrogen, and X 5 and X 6 At least one is nitrogen;

[0026] L C for:

[0027] in,

[0028] R a , R b , R c , R d , R e , R f , R gEach is independently selected from one or more of a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, a cycloalkyl group, a heteroalkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group, a silane group, an alkenyl group, a cycloalkenyl group, a heteroalkenyl group, an alkynyl group, an aryl group, and a heterocyclic aryl group; and in R a , R b , R c , R e , R f , R g At least one of them is C m D 2m+1 group, m is an integer from 0 to 20; preferably, m is an integer from 0 to 10;

[0029] The dotted line represents the ligand L A , L B or L C Coordination or bonding with metal M.

[0030] Preferably, the metal M is selected from Ir or Pt.

[0031] Preferably, the L A One or more selected from the following structures:

[0032]

[0033]

[0034]

[0035] Among them, X 1 , X 2 , X 3 , X 4 Each time it appears, it represents CR independently. 0 or N; preferably, X 1 , X 2 , X 3 , X 4 Each independently is CR 0 ;

[0036] Preferably, G is selected from O, S, or NR 4 ;

[0037] Preferably, R 0 , R 1 , R 2 , R 4 , R 5Each is independently selected from one or more of a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, a cycloalkyl group, a heteroalkyl group, a heterocycloalkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group, an alkenyl group, a cycloalkenyl group, an isoalkenyl group, an alkynyl group, an aryl group, a heteroaryl group, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile group, an isonitrile group, a thiol group, a sulfonyl group, a sulfinyl group, a phosphine group, and a phosphinooxy group; any adjacent substituents are optionally joined or fused to form a polycyclic ring, preferably a five-membered ring or a six-membered ring.

[0038] Preferably, the X 1 , X 2 , X 3 , X 4 Each independently represents CR 0 ; T is selected from O, S, NR 1 , or CR 1 R 2 ; G is selected from O, S, CR 2 R 3 or NR 4 ; Z represents CR if they are the same or different 5 ;

[0039] R 0 , R 2 , R 3 , R 4 , R 5 , R a , R b , R c , R d , R e , R f are independently selected from a hydrogen atom, a deuterium atom, a fluorine atom, a nitrile group, R A1 -R A55 , R B1 -R B45 , R C1 -R C295 A group of people; among them,

[0040] R A1 -R A55 The structural formula is as follows:

[0041]

[0042]

[0043] R B1 -R B45 The structural formula is as follows:

[0044]

[0045]

[0046] R C1 -R C295 The structural formula is as follows:

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054] Preferably, the L A Select one of Formula LA1-Formula LA225, the specific structure of Formula LA1-Formula LA225 is as follows:

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061] Preferably, the L B Select one of Formula LB1-Formula LB220, the specific structure of Formula LB1-Formula LB220 is as follows:

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070] Preferably, the Lc is selected from one of Formula LC1 to Formula LC40, and the specific structures of Formula LC1 to Formula LC40 are shown as follows:

[0071]

[0072]

[0073] Preferably, the molecular formula of the metal complex is Ir(LAi)3, Ir(LAi)2(LCw), Ir(LBj)2(LCw) or Pt(LAi)(LCw); wherein i is an integer of 1-225, j is an integer of 1-220, and w is an integer of 1-40;

[0074] Preferably, the molecular formula of the metal complex is Ir(LAi)3 or Ir(LAi)2(LCw).

[0075] "Halo", "halogen", "halogen atom" or "halide" within the meaning of the present invention includes fluorine, chlorine, bromine and iodine.

[0076] Alkyl in the sense of the present invention encompasses both straight-chain and branched alkyl groups, preferred alkyl groups are those having 1 to 40 carbon atoms and in which individual hydrogen atoms or -CH2- groups may also be substituted, including primarily 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.

[0077] Alkoxy 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.

[0078] Heteroalkyl is preferably an alkyl radical having 1 to 40 carbon atoms and is taken to mean radicals in which individual hydrogen atoms or -CH2- radicals may be replaced by oxygen, sulfur or halogen atoms and is taken to mean alkoxy, alkylthio, fluorinated alkoxy, fluorinated alkylthio, in particular methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio, tert-butylthio, trifluoromethylthio, trifluoromethoxy, pentafluoroethoxy, pentafluoroethylthio, 2,2,2-trifluoroethoxy, 2,2,2-trifluoroethylthio, vinyloxy, vinylthio, propenyloxy, propenylthio, butenylthio, butenyloxy, pentenyloxy, pentenylthio, cyclopentenyloxy, cyclopentenylthio, hexenyloxy, hexenylthio, cyclohexenyloxy, cyclohexenylthio, ethynyloxy, ethynylthio, propynyloxy, propynylthio, butynyloxy, butynylthio, pentynyloxy, pentynylthio, hexynyloxy, hexynylthio.

[0079] Generally speaking, the cycloalkyl and cycloalkenyl groups according to the present invention may be cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptyl, cycloheptenyl, wherein one or more -CH2- groups may be replaced by the above-mentioned alkyl or alkoxy groups; in addition, one or more hydrogen atoms may also be replaced by a deuterium atom, a halogen atom or a nitrile group.

[0080] Alkynyl groups within the meaning of the present invention comprise straight-chain and branched alkynyl groups, preferably alkynyl groups are alkynyl groups containing 2 to 40 carbon atoms.

[0081] Alkenyl in the sense of the present invention comprises straight-chain and branched alkenyl groups, preferably alkenyl groups are alkenyl groups containing 2 to 40 carbon atoms.

[0082] "Aralkyl" or "arylalkyl" in the sense of the present invention are used interchangeably and encompass alkyl groups having aromatic groups as substituents, additionally, aralkyl groups may be optionally substituted.

[0083] Aryl or aromatic groups in the sense of the present invention contain 5 to 60 carbon atoms, heteroaryl groups in the sense of the present invention contain 2 to 60 carbon atoms and at least one heteroatom, provided that the sum of carbon atoms and heteroatoms is at least 5; the heteroatoms are preferably selected from N, O or S. Aryl or heteroaryl here encompasses monocyclic groups and polycyclic systems. Polycyclic rings may have two carbon atoms as two adjacent rings or two or more rings common to each other, which are called "fused", wherein at least one of the rings is aromatic, for example the other rings may be cycloalkyl, cycloalkenyl, aryl, heterocyclic and / or heteroaryl.

[0084] The alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclyl, aryl and heteroaryl groups may be optionally substituted with one or more substituents selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, cycloamino, silanyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, thiol, sulfinyl, sulfonyl, phosphino and combinations thereof.

[0085] As used herein, "substituted" means that a substituent other than hydrogen is bonded to the relevant position, such as carbon. Thus, for example, in R 0 When replaced by a single, then an R 0 must not be hydrogen. Similarly, in R 0 When disubstituted, the two R 0 must not be hydrogen. Similarly, in R 0 When not replaced, R 0 Hydrogen for all available positions.

[0086] It should be understood that when describing a molecular fragment as a substituent or otherwise attached to another moiety, its name can be written as if it is a fragment, such as phenyl, phenylene, naphthyl, dibenzofuranyl, generally or as if it is the entire molecule. These different ways of naming substituents or attached fragments are considered equivalent.

[0087] The second object of the present invention is to provide the use of the metal complex mentioned above in the preparation of an organic electroluminescent element or in the preparation of an organic electroluminescent material.

[0088] The third object of the present invention is to provide an organic electroluminescent element, which includes a substrate, an anode, a cathode, a capping layer and at least one organic layer arranged between the anode and the cathode, wherein the organic layer includes the metal complex described above.

[0089] In some embodiments, the organic layer may be an emissive layer and the compound as described herein may be an emissive dopant or a non-emissive dopant.

[0090] In some embodiments, the organic layer may further comprise a host, wherein the host comprises at least one selected from the group consisting of triphenylene, carbazole, indolecarbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, 5,9-dioxa-13b-boronaphtho[3,2,1-de]anthracene, aza-triphenylene, aza-carbazole, aza-indolecarbazole, aza-dibenzothiophene, aza-dibenzofuran, aza-dibenzoselenophene and aza-(5,9-diaza-13b-boronaphtho[3,2,1-de]anthracene), wherein any substituent in the host group is a non-fused substituent independently selected from the group consisting of: C n H 2n+1 , OC n H 2n+1 ,OAr 1 、N(C n H 2n+1 2. NAr 1 Ar 2 、CH=CH-C n H 2n+1 、C≡CC n H 2n+1 ,Ar 1 ,Ar 1 -Ar 2 , C n H 2n -Ar 1 or no substituent, wherein n 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.

[0091] Preferably, the host material contained in the aforementioned organic layer may be, for example, a host group selected from the following:

[0092]

[0093] and combinations thereof.

[0094] In some embodiments, the organic layer may further include a host and a dopant, wherein the dopant includes a metal complex disclosed herein.

[0095] In some embodiments, the metal complex as described herein may be a sensitizer; wherein the device may further comprise an acceptor; and wherein the acceptor may be selected from the group consisting of: a fluorescent emitter, a delayed fluorescent emitter, and combinations thereof.

[0096] In yet another aspect, an OLED disclosed herein may further comprise an emissive region comprising a compound as disclosed in the above compounds section disclosed herein.

[0097] 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 electroluminescent device 100 is shown. The illustration is not necessarily drawn to scale. The organic electroluminescent 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, a hole blocking layer 107, an electron transport layer 108, an electron injection layer 109, a cathode 110, and a capping layer (CPL) 111. The device 100 may be manufactured by depositing the described layers in order.

[0098] Figure 2 A schematic diagram of an inverted organic electroluminescent device 200 is shown. The organic electroluminescent device 200 includes a substrate 201, a cathode 202, a light-emitting layer 203, a hole transport layer 204, and an anode 205. The organic electroluminescent device 200 can be prepared by depositing the described layers in sequence. Because the most common OLED device has a cathode disposed on the anode, and the organic electroluminescent device 200 has the cathode 202 disposed under the anode 205, the organic electroluminescent device 200 can be referred to as an "inverted" organic light-emitting device. In the corresponding layers of the organic electroluminescent device 200, materials similar to those described with respect to the organic electroluminescent device 100 can be used. Figure 2 One example is provided of how some layers may be omitted from the structure of the organic electroluminescent device 100 .

[0099] Figure 1 and Figure 2The simple layered structure described 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 the organic electroluminescent device 200, the hole transport layer 204 transports holes and injects holes into the light-emitting layer 203, and may be described as a hole transport layer or a hole injection layer. In one embodiment, the OLED may be described as having an organic layer disposed between the cathode and the 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.

[0100] 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.

[0101] 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 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 thermal imaging, thermal transfer, inkjet printing or nozzle printing. Soluble compounds, for example, are obtained by appropriately substituting the compounds shown in the general formula (I). These methods are also particularly suitable for oligomers, dendritic macromolecules 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.

[0102] 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, or under the substrate, the electrode, or beside 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 combination of materials may be used for the barrier layer. The barrier layer may incorporate 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 considered 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.

[0103] 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.

[0104] 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.

[0105] In some embodiments, the organic layer comprises an emissive layer and the metal complex is an emissive material.

[0106] In some embodiments, the organic layer further comprises a host material.

[0107] In some embodiments, the organic layer further comprises at least two host materials.

[0108] The materials described herein as being suitable for use in a particular layer in an organic light-emitting device can be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a wide variety of hosts, transport layers, barrier layers, injection layers, electrodes, and other layers that may be present. The materials described or mentioned below are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

[0109] The fourth object of the present invention is to provide a consumer product comprising an OLED, wherein the OLED comprises an anode, a cathode and an organic layer arranged between the anode and the cathode, and the organic layer comprises the metal complex described above.

[0110] In some embodiments, the consumer product can be one of the following: a flat panel display, a computer monitor, a medical monitor, a television, a sign, a light for interior or exterior lighting and / or signaling, a head-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cellular telephone, a tablet computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay having a diagonal of less than 2 inches, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.

[0111] The preparation methods are generally known to those skilled in the art, and they can apply them to organic electroluminescent elements comprising the metal complex according to the invention without inventive step.

[0112] 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.

[0113] 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:

[0114] Cleaning process: Use cleaning agent, deionized water, organic solvent, etc. to clean the glass substrate with ITO;

[0115] 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;

[0116] A step of forming a hole transport layer: forming a hole transport layer on the hole injection layer by vacuum evaporation;

[0117] 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;

[0118] 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;

[0119] 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.

[0120] Compared with the prior art, the present invention has the following beneficial effects:

[0121] The metal complex described in the present invention is a novel carbazole, carbazole or azacarbazole ligand, which can be used as an electrophosphorescent material. The metal complex described in the present invention electroluminescently emits red light with high luminous efficiency. At the same time, the material has good thermal stability, is easy to prepare, and is easy to sublimate and purify, and has a very broad market prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0122] Figure 1 is a schematic diagram of an organic electroluminescent device 100 of the present invention;

[0123] Figure 1 101 is a substrate, 102 is an anode layer, 103 is a hole injection layer, 104 is a hole transport layer, 105 is an electron blocking layer, 106 is a light emitting layer, 107 is a hole blocking layer, 108 is an electron transport layer, 109 is an electron injection layer, 110 is a cathode layer, and 111 is a CPL layer.

[0124] Figure 2 is a schematic diagram of an inverted organic electroluminescent device 200 of the present invention;

[0125] Figure 2 In the figure, 201 is a substrate, 202 is a cathode, 203 is a light-emitting layer, 204 is a hole transport layer, and 205 is an anode. DETAILED DESCRIPTION

[0126] 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 the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0127] In the present invention, the preparation methods are conventional methods unless otherwise specified. The raw materials used can be obtained from public commercial channels unless otherwise specified, and the percentages are mass percentages unless otherwise specified. In the series of novel metal complexes provided by the present invention, all reactions are carried out under well-known suitable conditions, and some involve simple organic preparations, such as the preparation of phenylboronic acid derivatives, which can be synthesized by skilled operation skills and are not described in detail in the present invention.

[0128] Example 1

[0129] Preparation of compound Ir(LA16)2(LC26):

[0130] The preparation method of the metal complex Ir(LA16)2(LC26) comprises the following steps:

[0131] Step 1: Preparation of compound Int-1

[0132]

[0133] 10.0 mmol of compound LA16 and 5.0 mmol of IrCl3·3H2O were dispersed in 30 mL of ethylene glycol ethyl ether and 10 mL of water. Under nitrogen protection, the temperature was raised to reflux for 24 hours. The mixture was cooled to room temperature, filtered, the filter cake was washed with water, and vacuum dried to obtain compound Int-1 as a red solid. The yield was 68%.

[0134] Step 2: Preparation of compound Ir(LA16)2(LC26)

[0135]

[0136] 5.0mmol of compound Int-1 and 15.0mmol of 3,7-diethylnonane-4,6-dione-3,5,5,7-d4 and 25.0mmol of anhydrous potassium 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. After cooling to room temperature, the reaction solution was poured into water and extracted with dichloromethane. The organic phase was dried and filtered. The filtrate was concentrated under reduced pressure and the residue was separated and purified by silica gel column to obtain compound Ir(LA16)2(LC26), a red solid. Yield: 47%, HRMS: 1048.4406[M+H]+ .

[0137] Example 2

[0138] Preparation of compound Ir(LB164)2(LC32):

[0139] The preparation method of the metal complex Ir(LB164)2(LC32) comprises the following steps:

[0140] Step 1: Preparation of compound Int-2

[0141]

[0142] 5.0 mmol of compound LB164 and 2.5 mmol of IrCl3·3H2O were dispersed in 24 mL of ethylene glycol ethyl ether and 8 mL of water. Under nitrogen protection, the temperature was raised to reflux for 24 hours. The mixture was cooled to room temperature, filtered, the filter cake was washed with water, and vacuum dried to obtain compound Int-2 as a red solid. The yield was 59%.

[0143] Step 2: Preparation of compound Ir(LB164)2(LC32)

[0144]

[0145] 5.0mmol of compound Int-2 and 15.0mmol of 3,7-diethyl-3,7-di(methyl-d3)nonane-4,6-dione-5,5-d2 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 mixture was cooled to room temperature, poured into water, extracted with dichloromethane, and 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(LB164)2(LC32), a red solid, with a yield of 55%, HRMS: 1016.5602[M+H] + .

[0146] Example 3

[0147] Referring to the similar synthesis method of Example 1 and Example 2, an iridium chloride bridge compound was prepared by a similar method as the first step of Example 1 or Example 2:

[0148]

[0149] In the second step, referring to the synthesis method similar to the second step of Example 1 and Example 2, only the iridium chloride bridge compound prepared in the first step is subjected to coordination reaction with LC to prepare the prepared compound: Ir(LAi)2(LCw) or Ir(LBj)2(LCw), where i is an integer of 1-225, j is an integer of 1-220, and w is an integer of 1-40.

[0150]

[0151] Example 4

[0152] Preparation of compound Ir(LA6)3:

[0153]

[0154] 5.0mmol of Tr(LA6)2(acac) prepared in Example 3 and 20.0mmol of LA6 were dispersed in 50mL of glycerol, heated to 180°C and stirred for reaction for 10 hours under nitrogen protection, cooled to room temperature, added dropwise to 100mL of 1N dilute hydrochloric acid, filtered, and the filter cake was washed with water and ethanol, and separated and purified by silica gel column to obtain compound Ir(LA6)3 as a red solid. Yield: 42%, HRMS: 1100.2652[M+H] + .

[0155] Example 5

[0156] Referring to the similar synthesis method of Example 5, compound Ir(LAi)3 or Ir(LBj)3 is prepared, i is an integer of 1-225, and j is an integer of 1-220. For example, in the process of preparing Ir(LBj)3, only Ir(LA6)2(acac) in Example 5 is replaced by Ir(LBj)2(acac), and LA6 in Example 5 is replaced by the corresponding LBj to prepare compound Ir(LBj)3.

[0157] Example 6

[0158] This embodiment provides an OLED device such as Figure 1 As shown, the preparation method of the OLED device includes the following steps:

[0159] (1) a glass substrate coated with an 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 an ultraviolet cleaning machine for 10 minutes, and bombarded with a low-energy cation beam;

[0160] (2) Place the treated ITO glass substrate in a vacuum chamber and evacuate to 1×10 -5 -9×10-3 Pa, metal aluminum is evaporated on the above ITO film as the anode layer, and the evaporated film thickness is Continue to evaporate compound HI01 as a hole injection layer, 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

[0161] (3) A layer of compound RP is continuously evaporated on the hole transport layer as an electron blocking layer, and the evaporated film thickness is

[0162] (4) On the electron blocking layer, a layer of the metal complex of the present invention and TDC is continuously evaporated as the light-emitting layer of the device, wherein TDC is the main material and the metal complex of the present invention is the doping material, the doping concentration of the metal complex of the present invention is 3%, and the evaporated film thickness is

[0163] (5) A layer of LiQ and ET material is further evaporated on the above-mentioned light-emitting layer as the electron transport layer of the device, wherein the mass ratio of LiQ to ET is 5:5, and the evaporated film thickness is Finally, a magnesium / silver alloy layer is sequentially evaporated on the electron transport layer as the cathode layer of the device, wherein the mass ratio of the magnesium / silver alloy layer is 3:7 and the evaporated film thickness is

[0164] Comparative Example 1

[0165] A comparative device EL-1 was prepared in the same manner as in Example 6, except that the metal complex doping material of the present invention was replaced by RD-A.

[0166] Comparative Example 2

[0167] A comparative device EL-2 was prepared in the same manner as in Example 6, except that the metal complex doping material of the present invention was replaced by RD-B.

[0168] The specific structures of the materials used in Example 6 and Comparative Examples 1 and 2 are as follows:

[0169]

[0170] Test example

[0171] According to the method of Example 6, different metal complexes prepared by the present invention were used as doping materials to make devices EL-3 to EL-7, and the data were normalized with EL-1 as the benchmark.

[0172] The roll-off ratio is calculated as follows:

[0173] Roll-off ratio = [1-(at a current density of 50 mA / cm2 The results are shown in Table 1.

[0174] Table 1

[0175]

[0176] The metal complex of the present invention is used as a doping material for the light-emitting layer. Compared with the comparative devices EL-1 and EL-2, the driving voltage is low and the luminous efficiency is improved. 2 Under these conditions, the LT95% life attenuation of the device is significantly improved, and from the roll-off ratio data, it shows a smoother attenuation curve.

[0177] Compared with the comparative material RD-A, the metal complex of the present invention can be concluded from the comparison of devices EL-3, EL-6 and EL-1 that the deuterated LC makes the metal complex as the doping material of the light-emitting layer, the driving voltage is reduced, the luminous efficiency is improved, and the effect of improving the LT95% life is particularly significant. From the comparison of devices EL-4 and EL-5 with EL-1, it is known that after the phenyl group is replaced by the aromatic group with a five-membered heterocyclic ring, the luminous efficiency is significantly improved, especially the metal complex Ir(LA16)2(LC26) with acenaphthylene ligand, the device LT95% life is 3.7 times that of the comparative device. It can be seen that when the metal complex of the present invention is used as a light-emitting material, it can obtain more excellent performance and a longer life.

[0178] The present invention also carried out the above test on the metal complexes prepared in other embodiments, and the results were basically the same. Due to limited space, they are not listed one by one.

[0179] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A metal complex, characterized in that The molecular formula of the metal complex is Ir(LAi)2(LCw); wherein, The LAi is selected from the group consisting of the following structural formulas: The LCw is selected from one of Formula LC1 to Formula LC40, and the specific structures of Formula LC1 to Formula LC40 are shown as follows:

2. An organic electroluminescent element, comprising a substrate, an anode, a cathode, a capping layer, and at least one organic layer disposed between the anode and the cathode, characterized in that: The organic layer includes the metal complex according to claim 1.

3. A consumer product comprising an OLED, characterized in that: The OLED comprises an anode, a cathode and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises the metal complex according to claim 1 .

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