Metal complex

Abstract

The present invention relates to iridium complexes suitable for use in organic electroluminescent devices, particularly as emitters.

Description

Detailed Description of the Invention

[0001] The present invention relates to an iridium complex suitable for use as a light emitter, particularly in an organic electroluminescent device.

[0002] According to the prior art, the triplet emitters used in phosphorescent organic electroluminescent devices (OLEDs) are particularly bis- and tris-ortho-metallated complexes having aromatic ligands. Examples of such complexes include tris(phenylpyridyl)iridium(III), and a number of related complexes (e.g., those with 1- or 3-phenylisoquinoline ligands, 2-phenylquinoline ligands, phenylcarbene ligands). This type of complex is also known as having a polypod ligand and is disclosed, for example, in US7,332,232 and WO2016 / 124304.

[0003] The object of the present invention is to provide a novel and particularly improved metal complex that is suitable as an emitter for use in OLEDs and has good lifetime and efficiency.

[0004] Surprisingly, this object is solved by a metal complex shown below, which comprises a tripod-type tetradentate ligand and one bidentate or two monodentate ligands, and has been found to be very suitable for use in organic electroluminescent devices. Therefore, the present invention provides these metal complexes and organic electroluminescent devices comprising these complexes.

[0005] The present invention provides a compound of formula (1).

Chemical formula

Chemical formula

Chemical formula

[0006] Accordingly, the complex has a tridentate tetradentate ligand having one bidentate and two monodentate sub-ligands, and one bidentate or two monodentate ligands. Here, what is meant by "bidentate sub-ligand" is that the sub-ligand in the complex coordinates or binds to iridium via two coordination sites, and what is meant by "monodentate sub-ligand" is that the sub-ligand coordinates or binds to iridium via one coordination site. "Tridentate" means that the ligand has three sub-ligands bonded to bridge V, or the bridge of formula (2) or (3). Since the ligand containing bridge V has one bidentate and two monodentate sub-ligands, as a result, overall, it is a tetradentate ligand, that is, a ligand that coordinates or binds to iridium via four coordination sites. The terms "bidentate sub-ligand" or "monodentate sub-ligand" in the sense of the present invention mean that when bridge V or the bridge of formula (2) or (3) does not exist, L 1 is a bidentate ligand, or L 2 and L 3 are monodentate ligands. However, as a result of the formal abstraction reaction of a hydrogen atom from this bidentate ligand or monodentate ligand and the joining to bridge V or the bridge of formula (2) or (3), it is not a separate ligand but is thus generated and is part of the tetradentate ligand, so the term "sub-ligand" is used for it.

[0007] The binding of the ligand or sub-ligand to iridium may be a coordination bond or a covalent bond, that is, the shared part of the bond may vary depending on the sub-ligand. In the present application, when it is described that a ligand or sub-ligand is coordinated or bound to iridium, this means, in the sense of the present invention, any kind of binding of the ligand or sub-ligand to iridium regardless of the shared part of the bond.

[0008] Two Rs or R 1When the radicals together form a ring system, it may be monocyclic or polycyclic, aliphatic, heteroaliphatic, aromatic or heteroaromatic. In this case, these radicals that together form the ring system may be adjacent, which means that these radicals are bonded to the same carbon atom or carbon atoms directly bonded to each other, and they may be further removed from each other. Preferably, it is this kind of ring formation of radicals bonded to the same carbon atom or carbon atoms directly bonded to each other.

[0009] In the context of the present invention, the term that two or more radicals may together form an alicyclic ring is understood to mean, inter alia, that two radicals are bonded to each other by a chemical bond with the formal deletion of two hydrogen atoms. This is illustrated by the following scheme.

Chemical formula

[0010] The formation of fused aromatic or heteroaromatic groups is also possible, as illustrated by the following scheme.

Chemical formula

[0011] Furthermore, the above term is also understood to mean that when one of the two radicals is hydrogen, the second radical bonds at the position where the hydrogen atom is bonded to form a ring. This is illustrated by the following scheme.

Chemical formula

[0012] In the context of the present invention, a heteroalicyclic group is an aliphatic cyclic group having at least one heteroatom as part of the ring. Preferably, it has one or two heteroatoms as part of the ring, where the heteroatom is preferably selected from the group consisting of nitrogen, oxygen and sulfur.

[0013] An aryl group in the meaning of the present invention contains 6 to 40 carbon atoms. A heteroaryl group in the meaning of the present invention contains 2 to 40 carbon atoms and at least one heteroatom, provided that the total of carbon atoms and heteroatoms is at least 5. The heteroatom is preferably selected from N, O and / or S. In this case, the heteroaryl group preferably contains 3 or less heteroatoms. Here, the aryl group or heteroaryl group means a single aromatic ring (i.e., benzene) or a single heteroaromatic ring (e.g., pyridine, pyrimidine, thiophene, etc.), or a fused aryl or heteroaryl group (e.g., naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, etc.).

[0014] An aromatic ring system in the meaning of the present invention contains 6 to 40 carbon atoms in the ring system. A heteroaromatic ring system in the meaning of the present invention contains 1 to 40 carbon atoms and at least one heteroatom in the ring system, provided that the total of the carbon atoms and the heteroatoms is at least 5. The heteroatom is preferably selected from N, O and / or S. An aromatic or heteroaromatic ring system in the meaning of the present invention is not necessarily construed to mean a system containing only aryl or heteroaryl groups. Instead, a plurality of aryl or heteroaryl groups may be further interposed by non-aromatic units (preferably with less than 10% atoms other than H), such as carbon, nitrogen or oxygen atoms, or a carbonyl group. For example, systems such as 9,9'-spirobifluorene, 9,9'-diarylfluorene, triarylamine, diaryl ether, stilbene, etc. are regarded as aromatic ring systems in the meaning of the present invention, and systems in which two or more aryl groups are interposed by, for example, a linear or cyclic alkyl group, or a silyl group, are the same. Further, a system in which two or more aryl or heteroaryl groups are directly bonded to each other (for example, biphenyl, terphenyl, quarterphenyl or bipyridine) is also regarded as an aromatic or heteroaromatic ring system. Preferred aromatic or heteroaromatic ring systems are simple aryl or heteroaryl groups, and groups in which two or more aryl or heteroaryl groups are directly connected by a difference (for example, biphenyl, or bipyridine, and fluorene or spirobifluorene).

[0015] In the meaning of the present invention, the term "alkyl group" is used as a term encompassing both linear or branched alkyl groups and cyclic alkyl groups. Similarly, the terms "alkenyl group" and "alkynyl group" are used as terms encompassing both linear or cyclic alkenyl or alkynyl groups and cyclic alkenyl or alkynyl groups. A cyclic, alkyl, alkoxy or thioalkoxy group in the meaning of the present invention is construed to mean a monocyclic, bicyclic, or polycyclic group.

[0016] In the meaning of the present invention, C1-~C 20- An alkyl group (furthermore, these individual hydrogen atoms or CH2 groups may be substituted by the groups described above) means, for example, methyl, ethyl, n-propyl, i-propyl, cyclopropyl, n-butyl, i-butyl, s-butyl, t-butyl, cyclobutyl, 2-methylbutyl, n-pentyl, s-pentyl, t-pentyl, 2-pentyl, neopentyl, cyclopentyl, n-hexyl, s-hexyl, t-hexyl, 2-hexyl, 3-hexyl, neohexyl, cyclohexyl, 1-methylcyclopentyl, 2-methylpentyl, n-heptyl, 2-heptyl, 3-heptyl, 4-heptyl, cycloheptyl, 1-methylcyclohexyl, n-octyl, 2-ethylhexyl, cyclooctyl, 1-bicyclo[2.2.2]octyl, 2-bicyclo[2.2.2]octyl, 2-(2,6-dimethyl)octyl, 3-(3,7-dimethyl)octyl, adamantyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, 1,1-dimethyl-n-hex-1-yl, 1,1-dimethyl-n-hept-1-yl, 1,1-dimethyl-n-oct-1-yl, 1,1-dimethyl-n-dec-1-yl, 1,1-dimethyl-n-dodec-1-yl, 1,1-dimethyl-n-tetradec-1-yl, 1,1-dimethyl-n-hexadec-1-yl, 1,1-dimethyl-n-octadec-1-yl, 1,1-diethyl-n-hex-1-yl, 1,1-diethyl-n-hept-1-yl, 1,1-diethyl-n-oct-1-yl, 1,1-diethyl-n-dec-1-yl, 1,1-diethyl-n-dodec-1-yl, 1,1-diethyl-n-tetradec-1-yl, 1,1-diethyl-n-hexadec-1-yl, 1,1-diethyl-n-octadec-1-yl, 1-(n-propyl)cyclohex-1-yl, 1-(n-butyl)cyclohex-1-yl, 1-(n-hexyl)cyclohex-1-yl, 1-(n-octyl)cyclohex-1-yl - and 1-(n-decyl)cyclohex-1-yl radicals. An alkenyl group means, for example, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl or cyclooctadienyl.The alkynyl group is understood to mean, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or octynyl. OR. 1 The group is understood to mean, for example, methoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy or 2-methylbutoxy.

[0017] An aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms may be substituted by the above radicals in each case and may be linked to the aromatic or heteroaromatic system at any position. For example, benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, perylene, fluoracene, benzofluoracene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans-indenofluorene, cis- or trans-monobenzoindenofluorene, cis- or trans-dibenzoindenofluorene, torquene, isotorquene, spirotorquene, spiroisotorquene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthroimidazole, pyridineimidazole, pyrazineimidazole, quinoxalineimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene, 4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenoxazine, phenothiazine, fluorubine, naphthyridine, azacarbazole, benzocarbazole, phenanthroline, 1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1,2,3-oxazole, 1,2,It is understood to mean groups derived from 4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazole, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine, pteridine, indolizine and benzothiazole.,

[0018] In a preferred form, the compounds of the invention are electrically uncharged. In this case, iridium is Ir(III). The charge neutrality is achieved by the balance between the charges of the ancillary ligand and the ligands L 1 ~L 4 and the charge of the trivalent iridium. Here, L 1 may be uncharged, monoanionic or dianionic. L 2 and L 3 may each be uncharged or monoanionic. Examples of suitable combinations of the ancillary ligand and the ligands L 1 ~L 4 are shown in the following table.,

Chemical formula

[0019] In a preferred form of the invention, L 1 is monoanionic, and therefore the first six items in the table are preferred.,

[0020] The preferred form of the bridgehead V, that is, the structure of formula (2) or (3), will be described later.,

[0021] In a preferred form of the invention, all X 1 groups of the group of formula (2) are CR, and the central trivalent ring of formula (2) is benzene or all X 1The base is a nitrogen atom, and the central trivalent ring of formula (2) is triazine. More preferably, all X 1 groups are the same or different and are CR.

[0022] The following applies to the preferred R radicals of the central benzene ring of formula (2) or the central cyclohexane ring of formula (3): R is the same or different at each occurrence and is H, D, F, CN, OR 1 , a linear alkyl group having 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, preferably 3 to 6 carbon atoms (each of these may be substituted by one or more R 1 radicals, but is preferably unsubstituted), or an aromatic or heteroaromatic ring atom having 5 to 24 aromatic ring atoms, preferably 6 to 12 aromatic ring atoms, and in each case may be substituted by one or more R 1 radicals, and at the same time, the R radical may form a ring system together with the R 2 radical of X; R 1 is the same or different at each occurrence and is H, D, F, CN, OR 2 , a linear alkyl group having 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, preferably 3 to 6 carbon atoms (each of these may be substituted by one or more R 2 radicals, but is preferably unsubstituted), or an aromatic or heteroaromatic ring atom having 5 to 24 aromatic ring atoms, preferably 6 to 12 aromatic ring atoms, and in each case may be substituted by one or more radicals R 2 , and at the same time, two or more adjacent R 1 radicals may form a ring system together; R 2It is the same or different for each occurrence and is an aliphatic, aromatic and / or heteroaromatic organic radical having H, D, F, or 1 to 20 carbon atoms (where one or more hydrogen atoms may be replaced by F), preferably an aliphatic or aromatic hydrocarbyl radical having 1 to 12 carbon atoms.

[0023] More preferably, all X 1 groups of formula (2) are CH or CD, especially CH. Even more preferably, all R groups in the group of formula (3) are H or D, especially H, and the central ring in formula (3) is an unsubstituted cyclohexane group.

[0024] Preferred forms of the group of formula (2) or (3) are the structures of formulae (2a) and (3a) below.

Chemical formula

[0025] Subsequently, the preferred divalent arylene or heteroarylene unit A and the group of formula (4) appearing in the groups of formulae (2) and (3) will be described.

[0026] In a preferred form of the present invention, the symbol X 3 in the group of formula (4) is C, and thus the group of formula (4) is represented by the following formula (4’).

Chemical formula

[0027] The group of formula (4) or (4’) may represent a heteroaromatic 5-membered ring or a heteroaromatic 6-membered ring. In a preferred embodiment of the present invention, the group of formula (4) or (4’) contains 2 or less heteroatoms, more preferably 1 heteroatom, in an aryl or heteroaryl group. This does not mean that any substituent attached to this group cannot contain a heteroatom. Further, this definition does not mean that the formation of a ring by a substituent does not result in a fused aromatic or heteroaromatic structure (e.g., naphthalene, benzimidazole, etc.). Examples of suitable groups of formula (4) or (4’) are selected from benzene, pyridine, pyrimidine, pyrazine, pyridazine, pyrrole, furan, thiophene, pyrazole, imidazole, oxazole and thiazole.

[0028] A preferred form of the group of formula (4’) is a structure of the following formulas (4a) to (4q).

Chemical formula

[0029] One X in formula (4) 3 When the group is a carbon atom and the other X 3 When the group is a nitrogen atom, a preferred form of the group of formula (4) is a structure of the following formulas (4r) to (4y).

Chemical formula

[0030] Particularly preferably, it is ortho-phenylene, that is, the group of the above formula (4a).

[0031] When two or three groups of formula (4) are present, these may be the same or different. In a preferred embodiment of the present invention, when two or three groups of formula (4) are present, these groups are the same and have the same substituents.

[0032] As the A group, it is preferably the following combination: - All three A groups are the same group of formula (4), in particular the same group of formula (4a); - Two A groups are the same group of formula (4), in particular the same group of formula (4a), and the third A group is a CR2-CR2 group; - One A group is the same group of formula (4), in particular the same group of formula (4a), and the other two A groups are the same CR2-CR2 group; or - All three A groups are the same CR2-CR2 group.

[0033] Here, "the same group of formula (4)" or "the same group of formula (4a)" means that these groups all have the same skeleton and the same substituents. Furthermore, "the same CR2-CR2 group" means that these groups have the same substituents.

[0034] - The preferred R radicals of the -CR2-CR2- group are selected from the group consisting of H, D, F, and an alkyl group having 1 to 5 carbon atoms (where the hydrogen atom may be replaced by D or F, and adjacent Rs may together form a ring system). Particularly preferred R radicals of these groups are selected from H, D, CH3, and CD3, or two R radicals bonded to the same carbon atom, together with the carbon atom to which they are bonded, form a cyclopentane or cyclohexane ring. Very particularly preferred R radicals of this group are selected from H and D, particularly H.

[0035] As the A group, it is particularly preferably the following combination: - All three A groups are groups where R = H in formula (4a); - Two A groups are groups where R = H in formula (4a), and the third A group is a CH2-CH2 group; - One A group is a group where R = H in formula (4a), and the other two A groups are CH2-CH2 groups; or - All three A groups are CH2-CH2 groups.

[0036] More preferably, the structures of formulas (2) and (3) are selected from the structures of the following formulas (2a) to (2d) and (3a) to (3d).

Chemical Formula

[0037] More preferably, the substituents R of formulas (2a) to (2d) and (3a) to (3d) are the same or different for each occurrence and are H, D, or an alkyl group having 1 to 4 carbon atoms. Most preferably, R = H or D, particularly H. Therefore, particularly preferred forms of formulas (2a) to (2d) and (3a) to (3d) are the structures of the following formulas (2a-1) to (2d-1) and (3a-1) to (3d-1).

Chemical Formula

[0038] Subsequently, the bidentate ligand L 1 will be described. As described above, L 1 coordinates to iridium via one carbon atom and one nitrogen atom, or via two carbon atoms. In a preferred form, the ligand L 1 coordinates to iridium via one carbon atom and one nitrogen atom.

[0039] More preferably, it is the case where the metallacycle formed from iridium and the ligand L 1 is a 5-membered ring. The formation of the 5-membered ring is schematically shown below.

Chemical Formula

[0040] In a preferred embodiment of the present invention, the ancillary ligand L 1 is one of the structures of the following formulas (L 1 -1) and (L 1 -2).

Chemical formula

[0041] CyD coordinates via a ligand having no charge, or via an anionic nitrogen atom or via a carbene carbon atom, preferably via a nitrogen atom having no charge or via a carbene carbon atom. Further, CyC coordinates via an anionic carbon atom.

[0042] When two or more substituents, in particular two or more R radicals, together form a ring system, it is also possible for the ring system to be formed from substituents directly bonded to adjacent carbon atoms. Further, the substituents of CyC and CyD may form a ring, such that CyC and CyD together form a singly fused aryl or heteroaryl group as a bidentate ligand.

[0043] In a preferred form of the present invention, CyC is an aryl or heteroaryl group having 6 to 13 aromatic ring atoms, more preferably 6 to 10 aromatic ring atoms, and most preferably 6 aromatic ring atoms, coordinates to the iridium atom via a carbon atom, may be substituted by one or more R radicals, and is bonded to CyD via a covalent bond.

[0044] Preferred forms of the CyC group are the structures of the following formulas (CyC-1) to (CyC-20) (wherein, in each case, the CyC group is bonded to CyD at the position marked with ♯ and coordinates to iridium at the position marked with *).

Chemical formula

[0045] Preferably, no more than one symbol X in CyC is N, and more preferably all of the symbols X are CR. However, when the group of bridge V or formula (2) or (3) is attached to CyC, one symbol X is C, and the bridge of bridge V or formula (2) or (3) is attached to this carbon atom.

[0046] Particularly preferred CyC groups are the groups of the following formulas (CyC-1a) to (CyC-20a).

Chemical formula

Chemical formula

[0047] Among the (CyC-1) to (CyC-20) groups, preferred groups are the (CyC-1), (CyC-3), (CyC-8), (CyC-10), (CyC-12), (CyC-13) and (CyC-16) groups, and particularly preferred are the (CyC-1a), (CyC-3a), (CyC-8a), (CyC-10a), (CyC-12a), (CyC-13a) and (CyC-16a) groups.

[0048] In a more preferred embodiment of the present invention, CyD is a heteroaryl group having 5 to 13 aromatic ring atoms, more preferably 6 to 10 aromatic ring atoms, or a heteroalicyclic group having 5 or 6 ring atoms, preferably 5 ring atoms, which coordinates via an uncharged or anionic nitrogen atom or via a carbene carbon atom and may be substituted by one or more radicals R and is bonded to CyC via a covalent bond.

[0049] Preferred forms of the CyD group are the structures of the following formulas (CyD-1) to (CyD-23) (wherein the CyD group is bonded to CyC at the position specified by ♯ and to iridium at the position specified by * in each case).

Chemical formula

[0050] In this case, the (CyD-1)-(CyD-4) and (CyD-9)-(CyD-20) groups are coordinated to iridium via a nitrogen atom having no charge, the groups (CyD-5)-(CyD-8) are via a carbene carbon atom, and the (CyD-21)-(CyD-23) groups are via an anionic nitrogen atom.

[0051] Preferably, one or less symbols X in CyD is N, more preferably all symbols X are CR, provided that when the bridge V or the bridge of formula (2) or (3) is attached to CyD, one symbol X is C, and the bridge V or the bridge of formula (2) or (3) is attached to this carbon atom.

[0052] Particularly preferred CyD groups are the groups of the following formulas (CyD-1a)-(CyD-23a).

Chemical formula

[0053] (CyD-1)~(CyD-12) groups, preferred groups among them are (CyD-1), (CyD-2), (CyD-3), (CyD-4), (CyD-5) and (CyD-6) groups, especially (CyD-1), (CyD-2) and (CyD-3), and particularly preferably (CyD-1a), (CyD-2a), (CyD-3a), (CyD-4a), (CyD-5a) and (CyD-6a) groups, especially (CyD-1a), (CyD-2a) and (CyD-3a).

[0054] In a preferred form of the present invention, CyC is an aryl or heteroaryl group having 6 to 13 aromatic ring atoms, and at the same time, CyD is a heteroaryl group having 5 to 13 aromatic ring atoms. More preferably, CyC is an aryl or heteroaryl group having 6 to 10 aromatic ring atoms, and at the same time, CyD is a heteroaryl group having 5 to 10 aromatic ring atoms. More preferably, CyC is an aryl or heteroaryl group having 6 aromatic ring atoms, and CyD is a heteroaryl group having 6 to 10 aromatic ring atoms. At the same time, CyC and CyD may be substituted by one or more R radicals.

[0055] When at least one of the CyC or CyD groups has a suitable binding site of bridge V or the bridge of formula (2) or (3) (the suitable binding site is marked by "o" in the above formula), the above-mentioned preferred (CyC-1) to (CyC-20) and (CyD-1) to (CyD-21) groups may optionally be linked to each other.

[0056] When at least one of the CyC or CyD groups has a suitable binding site of the group of bridge V or the bridge of formula (2) or (3) (the suitable binding site is denoted by "o" in the above formula), it is particularly preferred that the CyC and CyD groups specifically identified as particularly preferred (that is, the groups of formula (CyC-1a) to (CyC-20a) and the groups of formula (CyD1-a) to (CyD-21a)) are linked to each other. Therefore, a combination in which neither CyC nor CyD has a suitable binding site to bridge V or the bridge of formula (2) or (3) is not preferred.

[0057] It is particularly preferred that one of the (CyC-1), (CyC-3), (CyC-8), (CyC-10), (CyC-12), (CyC-13) and (CyC-16) groups, particularly one of the (CyC-1a), (CyC-3a), (CyC-8a), (CyC-10a), (CyC-12a), (CyC-13a) and (CyC-16a) groups, is linked to one of the (CyD-1), (CyD-2) and (CyD-3) groups, particularly one of the groups of (CyD-1a), (CyD-2a) and (CyD-3a).

[0058] Preferred co-ligand (L 1 -1) has the structure of formula (L 1 -1-1) to (L 1 -1-3), and the preferred co-ligand (L 1 -2) has the structure of formula (L 1 -2-1) to (L 1 -2-5) and coordinates to iridium through the two positions specified by *.

Chemical formula

[0059] Particularly preferred ancillary ligand (L 1 -1) has the structure of formula (L 1 -1-1a) to (L 1 -1-3b), and particularly preferred ancillary ligand (L 1 -2) has the structure of formula (L 1 -2-1a) to (L 1 -2-5a), and coordinates to iridium through the two positions specified by *.

Chemical formula

[0060] When two R radicals (one of which is bonded to CyC and the other to CyD) form an aromatic ring system with each other, they may form a bridged ancillary ligand or may form an ancillary ligand occupying a single larger heteroaryl group as a whole. The ring formation between the substituents on CyC and CyD is preferably formed by a group according to one of the following formulas (5) to (14).

Chemical formula

[0061] At the same time, the group of formula (11) is preferably a six-membered ring formation, for example, the formula (L 1 -21) and (L 1 -22) shown.

[0062] Preferred ligands resulting from ring formation between two R radicals in CyC and CyD are of the structure of formula (L 1 -3) to (L 1 -30) shown below.

Chemical formula

Chemical formula

[0063] In the preferred forms of the secondary ligands of formula (L 1 -3) to (L 1 -30), all of the symbols X are CR or one symbol X is N and the other symbols X are CR.

[0064] In a further form of the present invention, in the (CyC-1) to (CyC-20) or (CyD-1) to (CyD-21) groups, or in the secondary ligands (L 1 -3) to (L 1 -30), when the R group bonded as a substituent adjacent to the nitrogen atom is not hydrogen or deuterium, it is preferable that one of the atoms X is N. This also applies to the preferred structures (CyC-1a) to (CyC-20a) or (CyD-1a) to (CyD-14b), and the substituent bonded adjacent to the non-coordinating nitrogen atom is preferably an R group that is not hydrogen or deuterium. In this case, this substituent R is preferably CF3, OCF3, an alkyl group having 1 to 10 carbon atoms, particularly a branched or cyclic alkyl group having 3 to 10 carbon atoms, OR 1 (where R 1is a group selected from an alkyl group having 1 to 10 carbon atoms, in particular a branched or cyclic alkyl group having 3 to 10 carbon atoms), a dialkylamino group having 2 to 10 carbon atoms, an aromatic or heteroaromatic ring system, or an aralkyl or heteroaralkyl group. These groups are sterically demanding groups. More preferably, this R radical may form a ring with an adjacent R radical.

[0065] A more suitable bidentate ligand L 1 is one of the structures of the following formulas (L 1 -31) and (L 1 -32).

Chemical formula

[0066] In the ligands (L 1 -31) and (L 1 -32), when two R radicals bonded to adjacent carbon atoms form an aromatic ring with each other, this ring, together with the two adjacent carbon atoms, is preferably of the structure of formula (15).

Chemical formula

[0067] In a preferred form of the ligand (L 1 -31) or (L 1 -32), no more than one group of formula (15) is present. Thus, the ligand is preferably of the following formula (L1 -(L - 33) to (L 1 is a secondary ligand of -(L - 38):

Chemical formula

[0068] In a preferred form of the present invention, in the secondary ligand of formula (L 1 -(L - 31) to (L 1 -(L - 38), there are a total of 0, 1, or 2 symbols X and when Y is present, Y is N. More preferably, there are a total of 0 or 1 symbols X and when Y is present, Y is N.

[0069] Formula (L 1 -(L - 33) to (L 1 -(L - 38) preferred form is the structure of the following formula (L 1 -(L - 33a) to (L 1 -(L - 38f).

Chemical formula

Chemical formula

Chemical formula

[0070] In a preferred form of the present invention, the X group coordinated to the metal at the ortho position is CR. In this radical, the R bonded for coordination to the metal at the ortho position is preferably selected from the group consisting of H, D, F, and methyl.

[0071] In a further form of the present invention, when there is an atom X, it is preferred that one of Y is N, and in this case, the substituent bonded adjacent to this nitrogen atom is an R group that is not hydrogen or deuterium. In this case, this substituent R is preferably CF3, OCF3, an alkyl group having 1 to 10 carbon atoms, in particular a branched or cyclic alkyl group having 3 to 10 carbon atoms, OR 1 (where R 1 is an alkyl group having 1 to 10 carbon atoms, in particular a branched or cyclic alkyl group having 3 to 10 carbon atoms), a dialkylamino group having 2 to 10 carbon atoms, an aromatic or heteroaromatic ring system, or a group selected from aralkyl or heteroaralkyl groups. These groups are sterically bulky groups. More preferably, this R radical may form a ring with an adjacent R radical.

[0072] In a preferred form of the present invention, L 1 is one of the following ligands (L 1 -39) and (L 1 -40) that coordinates to iridium through the two positions marked with an asterisk.

Chemical formula

Chemical formula

[0073] In this case, the R 1 radical on the nitrogen atom is as described above, preferably an alkyl group having 1 to 10 carbon atoms or an aromatic or heteroaromatic ring system having 6 to 24 aromatic ring atoms, optionally substituted by one or more R 2 radicals, more preferably an aromatic or heteroaromatic ring system having 6 to 18 aromatic ring atoms, optionally substituted by one or more R 2 radicals but preferably unsubstituted.

[0074] In a preferred form of the present invention, n = 0, 1 or 2, preferably 0 or 1, and most preferably 0.

[0075] In a further preferred form of the present invention, both substituents R’ bonded in the ortho position to the carbon atom (by which the group of formula (16) or (17) is bonded to the ligand L 1 ) are the same or different and are H or D.

[0076] In a preferred form of the present invention, X is the same or different for each occurrence and is CR. More preferably, one Z group is CR and the other Z group is CR'. More preferably, in the ligand (L 1 -39) or (L 1 -40), the X groups are the same or different for each occurrence and are CR, and at the same time, one Z group is CR and the other Z group is CR'. The ligand L 1 preferably has one of the following structures (L 1 -39a) or (L 1 -40a), where the bond to the bridge V or the bridge of formula (2) or (3) is at the position marked with "o".

Chemical formula

[0077] More preferably, the ligand of formula (L 1 -39) or (L 1 -40) has one of the following structures (L 1 -39a') and (L 1 -40a').

Chemical formula

[0078] The ligand of formula (L 1 -39) or (L 1 -40) or the R radical in the preferred form is preferably H, D, CN, OR 1 , a linear alkyl group having 1 to 6 carbon atoms, preferably 1, 2 or 3 carbon atoms, or a branched or cyclic alkyl group having 3, 4, 5 or 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, preferably 2, 3 or 4 carbon atoms (each of these may have one or more R 1It is selected from the group consisting of a phenyl group which may be substituted by a radical, or which may be substituted by one or more non-aromatic R1 radicals. Two or more radicals may also together form a ring system.

[0079] In this case, the substituent R bonded to the coordinating atom in the ortho position is preferably selected from the group consisting of H, D, F and methyl, more preferably H, D and methyl, and particularly H and D.

[0080] Furthermore, it is preferable that all substituents R which are ortho to R' are H or D.

[0081] Formula (L 1 -39) or (L 1 -40) when the R radicals in the ligand L 1 together form a ring system, it is preferably an aliphatic, heteroaliphatic or heteroaromatic ring system. Furthermore, it is preferably a ring formation between two R radicals on two rings of the ligand L 1 and preferably forms phenanthridine or phenanthridine (which may further contain a nitrogen atom). When the R radicals together form a heteroaromatic ring system, this preferably forms a structure selected from the group consisting of quinoline, isoquinoline, dibenzofuran, dibenzothiophene and carbazole (each of which may be substituted by one or more R 1 radicals and where each carbon atom in dibenzofuran, dibenzothiophene and carbazole may be replaced by N). Particularly preferred are quinoline, isoquinoline, dibenzofuran and azadibenzofuran. Here, at any possible position, a fused structure may also be attached. Preferred ligands L 1 having a fused benzo group have the structures of formula (L 1 -39b) to (L 1 -40e) shown below, where the bond to the bridge V is via the position marked "o".

Chemical formula

[0082] Preferred formulas (L 1 -39) or (L 1 -40) of the auxiliary ligand L 1 having a condensed benzofuran or azabenzofuran group are the structural formulas (L 1 -39f) to (L 1 -40m) shown below, where the bond to the bridge V is via the position marked with "o".

Chemical formula

[0083] As described above, R' is a group of formula (16) or (17). Here, the two groups are different only in that the group of formula (16) is bonded to the auxiliary ligand L 1 at the para position and the group of formula (17) is bonded to it at the meta position.

[0084] In a preferred form of the present invention, n = 0, 1 or 2, preferably 0 or 1, and most preferably 0.

[0085] In a more preferred form of the present invention, both substituents R'' bonded ortho to the carbon atom (by which the group of formula (16) or (17) is bonded to the phenylpyridine ligand) are the same or different and are H or D.

[0086] Preferred forms of the structure of formula (16) are the structures of formulas (16a) to (16h), and preferred forms of the structure of formula (17) are the structures of formulas (17a) to (17h).

Chemical formula

Chemical formula

[0087] The group of formula (16) or (17), or the preferred substituents R' of the preferred form, is selected from the group consisting of H, D, CN, and alkyl groups having 1 to 4 carbon atoms, more preferably H, D, methyl, cyclopentyl, 1-methylcyclopentyl, cyclohexyl or 1-methylcyclohexyl, particularly H, D or methyl.

[0088] Subsequently, the monodentate ancillary ligands L 2 and L 3 will be described. Here, L 2 and L 3 are the same or different each time they appear and are uncharged or monoanionic ancillary ligands.

[0089] In a preferred form of the present invention, L 2 and L 3is an aryl or heteroaryl group that is the same or different for each occurrence and has 5 to 13 aromatic ring atoms, more preferably 6 to 13 aromatic ring atoms, and most preferably 6 to 10 aromatic ring atoms, which is coordinated to iridium via one carbon atom or one nitrogen atom, each of which is part of an aryl or heteroaryl group, and may be substituted by one or more R radicals. When this group is coordinated to iridium via a carbon atom, this is a carbenic carbon atom that is anionic or uncharged. When this group is coordinated to iridium via a nitrogen atom, this may be uncharged or anionic.

[0090] L 2 and L 3 preferred forms of are the same or different for each occurrence and have the structure of the following formula (L 2 -1) / (L 3 -1) to (L 2 -55) / (L 3 -55), where the groups in each case are ligands to iridium at the position marked with *, and at the position marked with "o", coordinate to the bridgehead V or the group of formula (2) or (3).

Chemical formula

Chemical formula

Chemical formula

[0091] Here, (L 2 -1) / (L 3 -1) to (L 2 -22) / (L 3-22) The group is, via an anionic carbon atom, (L 2 -23) / (L 3 -23)~(L 2 -26) / (L 3 -26) and (L 2 -34) / (L 3 -34)~(L 2 -50) / (L 3 -50) The group is, via a nitrogen atom having no charge, (L 2 -27) / (L 3 -27)~(L 2 -33) / (L 3 -33) The group is, via a carbon atom having no charge, (L 2 -51) / (L 3 -51)~(L 2 -55) / (L 3 -55) The group coordinates to iridium via an anionic nitrogen atom.

[0092] Preferably, the symbol X of 1 or less is N, and most preferably, all symbols X are CR.

[0093] Particularly preferred L 2 and L 3 The group is a group of the following formula (L 2 -1a) / (L 3 -1a)~(L 2 -55a) / (L 3 -55a).

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0094] Preferred monodentate auxiliary ligand L 2 and L 3 has the structures (L 2 -1), (L 3 -1), (L 2 -23), (L 3 -23), (L 2 -27), (L 3 -27), (L 2 -28), (L 3 -28), (L 2 -32), (L 3 -32), (L 2 -33) and (L 3 -33). Particularly preferred monodentate auxiliary ligands L 2 and L 3 has the structures (L 2 -1a), (L 3 -1a), (L 2 -23a), (L 3 -23a), (L 2 -27a), (L 3 -27a), (L 2 -28a), (L 3 -28a), (L 2 -32a), (L 3 -32a), (L 2 -33a), (L 3 -33a), (L 2 -33b) and (L 3 -33b).

[0095] Subsequently, the preferred forms of the ligand L 4 will be described. As described above, L 4 may be monodentate or bidentate. When the ligand L 4 is monodentate, it is either uncharged or monoanionic. When the ligand L 4 is bidentate, it is either uncharged, monoanionic or dianionic. When the ligand L 4 is monodentate, these are preferably the same or different and coordinate via atoms selected from the group consisting of carbon, nitrogen, oxygen, sulfur and phosphorus. When the ligand L 4When it is bidentate, it preferably coordinates via two atoms selected from the group consisting of carbon, nitrogen, oxygen, sulfur and phosphorus, which may be the same or different.

[0096] Ligand L without a suitable charge 4 is the same or different each time it appears and is selected from the group consisting of carbon monoxide (CO), nitric oxide (NO), alkyl cyanides such as acetonitrile, aryl cyanides such as benzonitrile, alkyl isocyanides such as methyl isocyanide, tert-butyl isocyanide, adamantyl isocyanide, aryl isocyanides such as phenyl isocyanide, amines such as trimethylamine, triethylamine, morpholine, phosphines, especially halophosphines, trialkylphosphines, triarylphosphines or alkylarylphosphines such as trifluorophosphine, trimethylphosphine, tricyclohexylphosphine, tri-tert-butylphosphine, triphenylphosphine, tris(pentafluorophenyl)phosphine, dimethylphenylphosphine, methyldiphenylphosphine, bis(tert-butyl)phenylphosphine, phosphites such as trimethyl phosphite, triethyl phosphite, arsines such as trifluoroarsine, trimethylarsine, tricyclohexylarsine, tri-tert-butylarsine, triphenylarsine, tris(pentafluorophenyl)arsine, stibines such as trifluorostibine, trimethylstibine, tricyclohexylstibine, tri-tert-butylstibine, triphenylstibine, tris(pentafluorophenyl)stibine, nitrogen-containing heterocycles such as pyridine, pyridazine, pyrazine, pyrimidine, triazine and carbenes, especially Arduengo carbenes. Preferred monodentate ligands L without a suitable charge 4 is selected from the group consisting of CO, PF3 and trialkylphosphines, where the alkyl groups are the same or different each time they appear and have 1 to 10 carbon atoms.

[0097] Suitable monoanionic monodentate ligand L 4is identical or different for each occurrence and is a hydride, deuteride, halide F - , Cl - , Br - and I - , an alkylacetylide such as methyl-C≡C - , tert-butyl-C≡C - , an arylacetylide such as phenyl-C≡C - , cyanide, cyanate, isocyanate, thiocyanate, isothiocyanate, an aliphatic or aromatic alkoxide such as methoxide, ethoxide, propoxide, isopropoxide, tert-butoxide, phenoxide, an aromatic or aromatic thioalkoxide such as methanethiolate, ethanethiolate, propanethiolate, iso-propanethiolate, tert-thiobutoxide, thiophenoxide, amide such as dimethylamide, diethylamide, di-isopropylamide, morpholide, carboxylate such as acetate, trifluoroacetate, propionate, benzoate, an aryl group such as phenyl, naphthyl, and an anionic nitrogen-containing heterocycle such as pyrrolide, imidazolide, pyrazolide. At the same time, the alkyl groups of these groups are preferably C1-C 20 alkyl group, more preferably C1-C 10 alkyl group, most preferably C1-C4 alkyl group. The aryl group is understood to mean a heteroaryl group. These groups have the meanings described above. A preferred monoanionic monodentate ligand L 4 is CN.

[0098] A bidentate ligand L having no preferred charge or being mono- or dianionic 4are diamines such as ethylenediamine, N,N,N’,N’-tetramethylethylenediamine, propylenediamine, N,N,N’,N’-tetramethylpropylenediamine, cis- or trans-diaminocyclohexane, cis- or trans-N,N,N’,N’-tetramethyldiaminocyclohexane, imines such as 2-[(1-(phenylimino)ethyl]pyridine, 2-[(1-(2-methylphenylimino)ethyl]pyridine, 2-[(1-(2,6-di-isopropylphenylimino)ethyl]pyridine, 2-[(1-(methylimino)ethyl]pyridine, 2-[(1-(ethylimino)ethyl]pyridine, 2-[(1-(isopropylimino)ethyl]pyridine, 2-[(1-(tert-butylimino)ethyl]pyridine, diimines such as 1,2-bis(methylimino)ethane, 1,2-bis(ethylimino)ethane, 1,2-bis(isopropylimino)ethane, 1,2-bis(tert-butylimino)ethane, 2,3-bis(methylimino)butane, 2,3-bis(ethylimino)butane, 2,3-bis(isopropylimino)butane, 2,3-bis(tert-butylimino)butane, 1,2-bis(phenylimino)ethane, 1,2-bis(2-methylphenylimino)ethane, 1,2-bis(2,6-di-isopropylphenylimino)ethane, 1,2-bis(2,6-di-tert-butylphenylimino)ethane, 2,3-bis(phenylimino)butane, 2,3-bis(2-methylphenylimino)butane, 2,3-bis(2,6-di-isopropylphenylimino)butane, 2,3-bis(2,6-di-tert-butylphenylimino)butane, heterocycles containing two nitrogen atoms such as 2,Selected from 2'-bipyridine, o-phenanthroline, diphosphines such as bis(diphenylphosphino)methane, bis(diphenylphosphino)ethane, bis(diphenylphosphino)propane, bis(diphenylphosphino)butane, bis(dimethylphosphino)methane, bis(dimethylphosphino)ethane, bis(dimethylphosphino)propane, bis(diethylphosphino)methane, bis(diethylphosphino)ethane, bis(diethylphosphino)propane, bis(di-tert-butylphosphino)methane, bis(di-tert-butylphosphino)ethane, bis(tert-butylphosphino)propane, 1,3-diketonates derived from 1,3-diketones such as acetylacetone, benzoylacetone, 1,5-diphenylacetylacetone, dibenzoylmethane, bis(1,1,1-trifluoroacetyl)methane, 3-ketonates derived from 3-ketoesters such as ethyl acetoacetate, carboxylates derived from aminocarboxylic acids such as pyridine-2-carboxylic acid, quinoline-2-carboxylic acid, glycine, N,N-dimethylglycine, alanine, N,N-dimethylaminoalanine, salicyliminates derived from salicylimines such as methyl salicylimine, ethyl salicylimine, phenyl salicylimine, dialkoxides derived from diols such as ethylene glycol, 1,3-propylene glycol, and dithiolates derived from dithiols such as ethylene-1,2-dithiol, propylene-1,3-dithiol, bis(pyrazolylborate), bis(imidazolyl)borate, 3-(2-pyridyl)diazole, or 3-(2-pyridyl)triazole.,

[0099] More preferably, together with iridium, a bidentate monoanionic, uncharged, or dianionic ligand L having a cyclometalated five-membered or six-membered ring, particularly a cyclometalated five-membered ring, having at least one iridium-carbon bond, 4, particularly a monoanionic ligand. These are, in particular, ligands commonly used in phosphorescent metal complexes of organic electroluminescent devices, namely ligands of the phenylpyridine, naphthylpyridine, phenylquinoline, phenylisoquinoline type, etc. (each of which may be substituted by one or more radicals R). Those skilled in the art of phosphorescent electroluminescent devices are aware of many such ligands, and without exercising inventive techniques, additional ligands of this type can be selected as the ligand L of the compound of formula (1). 4 could be selected.

[0100] A suitable bidentate ligand L 4 is selected from the ligands of the following formulas (L 4 -1), (L 4 -2) and (L 4 -3).

Chemical formula

[0101] Here, CyD coordinates without having a charge or through an anionic nitrogen atom or through a carbene carbon atom. Further, CyC coordinates through an anionic carbon atom.

[0102] When two or more substituents, in particular two or more R radicals, together form a ring system, the ring system can be formed from substituents attached to directly adjacent carbon atoms. Furthermore, it is also possible for the substituents on CyC and CyD to together form a ring, such that CyC and CyD together may form one fused aryl or heteroaryl group as a bidentate ligand.

[0103] In a preferred form of the present invention, CyC is an aryl or heteroaryl group having 6 to 13 aromatic ring atoms, more preferably 6 to 10 aromatic ring atoms, and most preferably 6 aromatic ring atoms, which coordinates to the metal via a carbon atom, which may be substituted by one or more R radicals, and which is bonded to CyD via a covalent bond.

[0104] Preferred forms of CyC are structures of the following formulas (CyC-1) to (CyC-20), where the CyC group is bonded to CyD at the position marked with ♯ and coordinates to iridium at the position marked with *.

Chemical formula

[0105] Preferably, 1 or less of the symbols X in CyC is N, and more preferably all of the symbols X are CR.

[0106] Particularly preferred CyC groups are groups of the following formulas (CyC-1a) to (CyC-20a).

Chemical formula

Chemical formula

[0107] (CyC-1) to (CyC-20) groups, the preferred groups are (CyC-1), (CyC-3), (CyC-8), (CyC-10), (CyC-12), (CyC-13) and (CyC-16) groups, and particularly preferably, (CyC-1a), (CyC-3a), (CyC-8a), (CyC-10a), (CyC-12a), (CyC-13a) and (CyC-16a) groups.

[0108] In a more preferred embodiment of the present invention, CyD is a heteroaryl group having 5 to 13 aromatic ring atoms, more preferably 6 to 10 aromatic ring atoms, which coordinates to the metal via a nitrogen atom having no charge or via a carbene carbon atom, and which may be substituted by one or more R radicals and is bonded to CyC via a covalent bond.

[0109] Preferred forms of the CyD group are the structures of the following formulas (CyD-1) to (CyD-21), where the CyD group is bonded to CyC at the position marked with ♯ and coordinates to iridium at the position marked with * in each case.

Chemical formula

[0110] Here, the (CyD-1) to (CyD-4) and (CyD-7) to (CyD-18) groups coordinate to the metal via a nitrogen atom having no charge, the (CyD-5) to (CyD-6) groups coordinate to the metal via a carbene carbon atom, and the (CyD-19) to (CyD-21) groups coordinate to the metal via an anionic nitrogen atom.

[0111] Preferably, 1 or less of the symbols X in CyD is N, and more preferably all of the symbols X are CR.

[0112] Particularly preferred CyD groups are groups of the following formulas (CyD-1a) to (CyD-21a). [Chemical formula] Here, the symbols used have the meanings described above. Preferably, the substituent R is 3 or less, more preferably 2 or less, and most preferably 1 or less, and is not H or D.

[0113] Preferred groups among the (CyD-1) to (CyD-12) groups are the (CyD-1), (CyD-2), (CyD-3), (CyD-4), (CyD-5), and (CyD-6) groups, particularly the (CyD-1), (CyD-2), and (CyD-3) groups, and particularly preferably the (CyD-1a), (CyD-2a), (CyD-3a), (CyD-4a), (CyD-5a), and (CyD-6a) groups, particularly the (CyD-1a), (CyD-2a), and (CyD-3a) groups.

[0114] In a preferred embodiment of the present invention, CyC is an aryl or heteroaryl group having 6 to 13 aromatic ring atoms, and at the same time, CyD is a heteroaryl group having 5 to 13 aromatic ring atoms. More preferably, CyC is an aryl or heteroaryl group having 6 to 10 aromatic ring atoms, and at the same time, CyD is a heteroaryl group having 5 to 10 aromatic ring atoms. Most preferably, CyC is an aryl or heteroaryl group having 6 aromatic ring atoms, and CyD is a heteroaryl group having 6 to 10 aromatic ring atoms. At the same time, CyC and CyD may be substituted by one or more R radicals.

[0115] The above preferred groups (CyC-1) to (CyC-20) and (CyD-1) to (CyD-23) may be combined with each other according to requirements. It is particularly preferred that the CyC and CyD groups particularly preferably mentioned above, namely the groups of formula (CyC-1a) to (CyC-20a) and the groups of formula (CyD1-a) to (CyD-14b), are combined with each other. Most particularly preferably, one of the (CyC-1), (CyC-3), (CyC-8), (CyC-10), (CyC-12), (CyC-13) and (CyC-16) groups and in particular one of the (CyC-1a), (CyC-3a), (CyC-8a), (CyC-10a), (CyC-12a), (CyC-13a) and (CyC-16a) groups is combined with one of the (CyD-1), (CyD-2) and (CyD-3) groups, in particular one of the (CyD-1a), (CyD-2a) and (CyD-3a) groups.

[0116] Preferred ligand (L 4 -1) has the structure of formula (L 4 -1-1) to (L 4 -1-5).

Chemical formula

[0117] Particularly preferred auxiliary ligand (L 4 -1) has the structure of formula (L 4 -1-1a) to (L 4 -1-5a).

Chemical formula

[0118] When two R radicals, one of which is attached to CyC and the other to CyD, together form an aromatic ring system, this can result in a cross-linked ligand and a ligand that forms one larger heteroaryl group as a whole. The ring between the substituents on CyC and CyD is preferably formed by one of the groups of formulas (5) to (14), and the co-ligand L 1 is as shown above.

[0119] Preferred ligands L resulting from ring formation between two R radicals in different rings 4 are of the structures of the formulas (L 4 -3) to (L 4 -16) shown below.

Chemical formula

[0120] In the preferred forms of the co-ligands of the formulas (L 4 -4) to (L 4 -16), in total one symbol X is N and the other symbol X is CR, or all symbols X are CR.

[0121] In a further form of the present invention, when the R group bonded as a substituent adjacent to a nitrogen atom in the groups of the groups (CyC-1) to (CyC-20) or (CyD-1) to (CyD-14), or in the co-ligands (L 4 -4) to (L 4 -16) is not hydrogen or deuterium, it is preferred that one of the atoms X is N. This similarly applies to the preferred structures (CyC-1a) to (CyC-20a) or (CyD-1a) to (CyD-14b), where the substituent bonded adjacent to the non-coordinating nitrogen atom is preferably an R group that is not hydrogen or deuterium. In this case, the substituent R is preferably CF3, OCF3, an alkyl group having 1 to 10 carbon atoms, in particular a branched or cyclic alkyl group having 3 to 10 carbon atoms, OR 1 , where R 1is a group selected from an alkyl group having 1 to 10 carbon atoms, in particular a branched or cyclic alkyl group having 3 to 10 carbon atoms, a dialkylamino group having 2 to 10 carbon atoms, an aromatic or heteroaromatic ring system, or an aralkyl or heteroaralkyl group. These groups are sterically bulky groups. More preferably, the R radical may form a ring together with an adjacent R radical.

[0122] Even more suitable bidentate ligand L 4 has the structure of the following formula (L 4 -17).

Chemical formula

[0123] The preferred form of ligand (L 4 -17) is described in applications WO2011 / 044988, WO2014 / 094962, WO2014 / 094961 and WO2014 / 094960.

[0124] In a further form of the invention, L is a ligand of the following formula (L 4 -18) that coordinates to iridium via the two positions marked with *.

Chemical formula

[0125] The preferred form of ligand (L 4 -18) is the auxiliary ligands (L 1 -39) and (L 1has the same meaning as that described above at -40).

[0126] The ligand (L 4 -18)'s preferred form is the ligand of the following formula (L 4 -18a). [Chemical formula] Here, the symbols used have the meanings described above.

[0127] More preferably, the ligand of formula (L 4 -18) has one of the structures of the following formula (L 4 -18b). [Chemical formula] Here, the symbols used have the meanings described above.

[0128] Regarding the ligand of formula (L 4 -18) or the preferred R and R' in the preferred form, the co-ligands (L 1 -39) and (L 1 -40) described above apply similarly.

[0129] The preferred ligand L having a condensed benzo group 4 has the structures of the following formulas (L 4 -18c) to (L 4 -18h). [Chemical formula] Here, the ligands may each be substituted by one or more additional R radicals, and the condensed structure may be substituted by one or more R 1 radicals. Preferably, there are no additional R or R 1 radicals.

[0130] The preferred ligand L of formula (L 4 -18) having a condensed benzofuran or azabenzofuran group4 is of the structure of the formulas (L 4 -18i) to (L 4 -18y). [Chemical formula] Here, the ligand may each be substituted by one or more additional R radicals, and the fused structure may be substituted by one or more R 1 radicals. Preferably, there are no additional R or R 1 radicals. Similarly, the O in these structures can also be replaced by S or NR 1 .

[0131] The ligand L 4 in the preferred form of the substituent R' of formula (16) or (17) corresponds to the preferred form described above in (L 1 -39) and (L 1 -40).

[0132] L 4 has further forms which are bidentate dianionic ligands (L 4 -19) and (L 4 -20), and bidentate monoanionic ligands (L 4 -21) to (L 4 -24), each of which coordinates to iridium via two atoms specified by *. [Chemical formula] Here, R has the meaning described above, X is the same or different at each occurrence and is CR or N, provided that no more than two X's are N. Preferably, no more than one X is N, and more preferably, all X's are the same or different at each occurrence and are CR.

[0133] Preferably, the ligands are (L 4 -19a) to (L 4 -24a). [Chemical formula] Here, R has the meaning described above. Preferably, the substituent R is 3 or less, more preferably 2 or less, and most preferably 1 or less, and is not H or D.

[0134] Hereinafter, the above-mentioned auxiliary ligand L 1 , L 2 and / or L 3 , or the above-mentioned ligand L 4 The preferable substituents that may be present will be described. These substituents may be present in the divalent arylene or heteroarylene group in the structure of formula (4).

[0135] In a preferred form of the present invention, the metal complex of the present invention is bonded to adjacent carbon atoms and forms a ring together by one of the following formulas, and includes two R substituents or two R 1 substituents. In this case, the two R substituents forming this alicyclic ring may be present in the bridge V or the bridge of formula (2) or (3) and / or one bidentate auxiliary ligand and / or one monodentate ligand. The alicyclic ring formed by the two R substituents together or the two R 1 substituents together by ring formation is preferably described by one of the following formulas (18) to (24). [Chemical formula] Here, R 1 and R 2 have the meanings described above, the dotted bond indicates the bond between two carbon atoms in the ligand, and further: G has 1, 2 or 3 carbon atoms and may be substituted by one or more R 2 radicals, an alkylene group, -CR 2 =CR 2 -, or an ortho-bonded arylene or heteroarylene group having 5 to 14 aromatic ring atoms and may be substituted by one or more R 2 radicals; R 3is the same or different for each occurrence and is a straight-chain, alkyl or alkoxy group having H, F, 1 to 10 carbon atoms, a branched or cyclic, alkyl or alkoxy group having 3 to 10 carbon atoms (wherein the alkyl or alkoxy group, in each case, may be substituted by one or more R 2 radicals, and one or more non-adjacent CH2 groups may be R 2 C=CR 2 , C≡C, Si(R 2 )2, C=O, NR 2 , O, S or CONR 2 ), or has 5 to 24 aromatic ring atoms and may be substituted by one or more R 2 radicals in each case, an aromatic or heteroaromatic ring system, has 5 to 24 aromatic ring atoms and may be substituted by one or more R 2 radicals, an aryloxy or heteroaryloxy group; simultaneously, two R 3 radicals bonded to the same carbon atom may together form an aliphatic or aromatic ring system, thereby forming a spiro system; furthermore, R 1 may form an aliphatic ring system together with adjacent R or R 3 radicals.

[0136] In the structure of the present invention, when adjacent radicals form an aliphatic ring system, it is preferred that the latter has no acidic benzyl protons at all. The benzyl proton is understood to mean a proton bonded to the carbon atom directly bonded to the ligand. This can be achieved by the carbon atom of the aliphatic ring system directly bonded to the aryl or heteroaryl group being completely substituted and containing no bonded hydrogen atoms. For example, in formulas (18) to (24), the absence of acidic benzyl protons means that R 3is achieved when it is not hydrogen. This can also be achieved by the aliphatic ring system carbon atom directly bonded to the aryl or heteroaryl group being at the bridgehead in a bicyclic or polycyclic structure. Due to the spatial structure of the bicyclic or polycyclic ring, the proton bonded to the bridgehead carbon atom is significantly less acidic than the benzylic proton on the carbon atom not bonded within the bicyclic or polycyclic structure and is considered a non-acidic proton in the context of the present invention. Thus, in formulas (21) - (24), the absence of acidic benzylic protons is achieved by the fact that it is a bicyclic structure, and since the corresponding anion of the bicyclic structure is not mesomerically stabilized, R 1 is a result of being even less acidic than the benzylic proton when it is H. Thus, even when R 1 in formulas (21) - (24) is H, it is a non-acidic proton in the context of the present invention. In a preferred form of the present invention, R 3 is not H.

[0137] Preferred forms of the groups of formulas (18) - (24) are found in applications WO2014 / 023377, WO2015 / 104045, and WO2015 / 117718.

[0138] When the compounds of the present invention have R radicals that do not correspond to the above R radicals, these R radicals are the same or different each time they appear and are preferably H, D, F, Br, I, N(R 1 )2, CN, Si(R 1 )3, B(OR 1 )2, C(=O)R 1 , a straight-chain alkyl group having 1 - 10 carbon atoms, an alkenyl group having 2 - 10 carbon atoms, a branched or cyclic alkyl group having 3 - 10 carbon atoms (wherein the alkyl or alkoxy group may each be substituted by one or more radicals R 1 ), or having 5 - 30 aromatic ring atoms and in each case one or more R 1selected from the group consisting of aromatic or heteroaromatic ring systems, which may be substituted by radicals; simultaneously, two adjacent R radicals together, or an R radical together with R 1 may form a monocyclic or polycyclic, aliphatic or aromatic ring system. More preferably, these R radicals are the same or different each time they occur, and are H, D, F, N(R 1 )2, a linear alkyl group having 1 to 6 carbon atoms, a branched or cyclic alkyl group having 3 to 10 carbon atoms (where one or more hydrogen atoms may be replaced by D or F), or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, and in each case may be substituted by one or more R 1 radicals, selected from the group consisting of aromatic or heteroaromatic ring systems, and simultaneously, two adjacent R radicals together, or an R radical together with R 1 may form a monocyclic or polycyclic, aliphatic or aromatic ring system.

[0139] Preferred R 1 radicals attached to R are the same or different each time they occur, and are H, D, F, N(R 2 )2, CN, a linear alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a branched or cyclic alkyl group having 3 to 10 carbon atoms (where the alkyl group may be substituted by one or more R 2 radicals in each case), or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, and in each case may be substituted by one or more R 2 radicals, selected from the group consisting of aromatic or heteroaromatic ring systems; and simultaneously, two or more adjacent R 1 radicals together may form a monocyclic or polycyclic aliphatic ring system. Particularly preferred R 1 radicals attached to R are the same or different each time they occur, and are H, F, CN, a linear alkyl group having 1 to 5 carbon atoms, a branched or cyclic alkyl group having 3 to 5 carbon atoms (each of these may have one or more R 2which may be substituted by radicals), or an aromatic or heteroaromatic ring system having 5 to 13 aromatic ring atoms, in each case one or more radicals R 2 which may be substituted by 2 , is an aromatic or heteroaromatic ring system; simultaneously, two or more adjacent R 1 radicals may together form a monocyclic or polycyclic aliphatic ring system.

[0140] Preferred R 2 radicals are, each occurrence being the same or different, H, F, or an aliphatic hydrocarbyl radical having 1 to 5 carbon atoms, or an aromatic hydrocarbyl radical having 6 to 12 carbon atoms; simultaneously, two or more R 2 substituents may together form a monocyclic or polycyclic aliphatic ring system.

[0141] The above preferred forms can, if desired, be combined with one another. In a particularly preferred form of the present invention, the above preferred forms are applied simultaneously.

[0142] Examples of suitable structures of the present invention are the compounds shown below.

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0143] In principle, the compounds of the present invention can be prepared by various processes. Generally, for this purpose, an iridium compound reacts with a suitable free tetradentate ligand in the first step. The intermediate thus obtained then reacts with a monodentate ligand or a bidentate ligand to yield a product. This is shown below using the example of a simple tetradentate ligand having a monoanionic auxiliary ligand L 4 or a dianionic ligand L 4 in combination with two monoanionic ligands L 1 and two uncharged auxiliary ligands L 2 and L 3 . [Chemical]

[0144] Accordingly, the present invention further provides a method for preparing a compound of the present invention, which comprises reacting a suitable tetradentate ligand with an iridium alkoxide of formula (25), an iridium ketoketonate of formula (26), an iridium halide of formula (27), an iridium carboxylate of formula (28), an iridium-olefin-cyclopentadienyl complex of formula (29), or an iridium carboxylate of formula (30), and then reacting the intermediate thus obtained with a ligand L 4 . [Chemical] Here, R has the meaning described above, Hal = F, Cl, Br or I, and the iridium reactant may be present as the corresponding hydrate. R is preferably an alkyl group having 1 to 4 carbon atoms. The Olefins of formulas (29) and (30) are diolefins, typically 1,5-cyclooctadiene, and other diolefins such as cyclohexadiene or norbornadiene.

[0145] Similarly, iridium compounds having alkoxides and / or halides and / or hydroxy and ketoketonate radicals can be used. These compounds may have a charge. Corresponding iridium compounds particularly suitable as reactants are disclosed in WO2004 / 085449. Particularly suitable is [IrCl2(acac)2] - , such as Na[IrCl2(acac)2], metal complexes with acetylacetonate derivatives as ligands, such as Ir(acac)3 or tris(2,2,6,6-tetramethylheptane-3,5-dionate)iridium, and IrCl3·xH2O (wherein x is typically a number from 2 to 4).

[0146] The synthesis of the complex is preferably carried out as disclosed in WO2002 / 060910 and WO2004 / 085449. In this case, the synthesis is activated, for example, by thermal or photochemical methods and / or microwave radiation. Further, this synthesis can be carried out in an autoclave with elevation of pressure and / or temperature.

[0147] The reaction can be carried out without adding a solvent or a melting aid in the melt of the corresponding ligand to be ortho-metalated. If desired, a solvent or a melting aid can also be added. Suitable solvents are protic or aprotic solvents such as aliphatic and / or aromatic alcohols (methanol, ethanol, isopropanol, t-butanol, etc.), oligoalcohols and polyalcohols (ethylene glycol, 1,2-propanediol or glycerol, etc.), alcohol ethers (e.g., ethoxyethanol, diethylene glycol, triethylene glycol, polyethylene glycol, etc.), ethers (di- and triethylene glycol dimethyl ether, diphenyl ether, etc.), aromatic, heteroaromatic and / or aliphatic hydrocarbons (toluene, xylene, mesitylene, chlorobenzene, pyridine, lutidine, quinoline, isoquinoline, tridecane, hexadecane, etc.), amides (DMF, DMAC, etc.), lactams (NMP), sulfoxides (DMSO), or sulfones (dimethyl sulfone, sulfolane, etc.). Suitable melting aids are compounds that are solid at room temperature but melt when the reaction mixture is heated to form a homogeneous melt and dissolve the reactants. Particularly suitable are biphenyl, m-terphenyl, triphenylene, R- or S-binaphthol or other corresponding racemates, 1,2-, 1,3- or 1,4-bisphenoxybenzene, triphenylphosphine oxide, 18-crown-6, phenol, 1-naphthol, hydroquinone, catechol, resorcinol, etc. Particularly preferred is the use of hydroquinone.

[0148] Furthermore, the synthesis can preferably be carried out in an anhydride medium in the presence of a carboxylic acid, as disclosed in the yet unpublished application EP19187468.4. Here, the iridium reactant used is preferably an iridium halide, iridium carboxylate, COD-iridium(I) compound, iridium ketoketonate, or one of the compounds of the above formulas (25) to (30). Particularly suitable carboxylic acids are selected from the group consisting of acetic acid, propionic acid, pivalic acid, benzoic acid, phenylacetic acid, adipic acid or mixtures thereof. When the iridium reactant used is a hydrate, preferably a dehydrating agent, in particular a carboxylic acid anhydride, carbonyl halide, trialkyl orthocarboxylate, carbodiimide, phosphorus pentoxide, thionyl chloride or phosphoryl chloride, is added. When the iridium reactant used is a halide, preferably a dehalogenating agent, in particular an alkali metal, alkaline earth metal, ammonium or zinc salt of a carboxylic acid, is added.

[0149] The same ancillary ligand L 2 and L 3 When ligands having are used for orthometalation, what is obtained is typically a racemic mixture of C1-symmetric complexes, i.e., the Δ and Λ enantiomers. These may be separated by standard methods (optical resolution by chiral material / column chromatography or crystallization).

[0150] Different ancillary ligands L 2 and L 3 When ligands having are used for complexation, typically obtained is a diastereomeric mixture of complexes that can be separated by standard methods (chromatography, crystallization, etc.).

[0151] By these steps (optionally followed by purification such as recrystallization or sublimation), the compounds of the invention of formula (1) can be obtained in high purity, preferably higher than 99% ( 1 determined by 1H NMR and / or HPLC).

[0152] The compounds according to the invention may be rendered soluble by suitable substitution (for example a relatively long alkyl group (from about 4 to 20 carbon atoms), in particular a branched alkyl group, or an aryl group optionally substituted (for example by a xylyl, mesityl or branched terphenyl or quaterphenyl group)). Another particular method for significantly improving the solubility of the metal complex is the use of a condensed aliphatic group, as shown for example in formulas (44) to (50) disclosed above. Such compounds dissolve in standard organic solvents (for example toluene or xylene) at room temperature in sufficient concentration to enable the preparation of the complex from the solution. These soluble compounds are particularly suitable for processing from solution (for example by printing processes).

[0153] For the production of the iridium complex of the present invention from the liquid phase, for example, by spin coating or printing methods, formulations of the metal complex according to the present invention are required. These formulations may be, for example, solutions, dispersions or emulsions. For this purpose, it may be preferable to use a mixture of two or more solvents. Suitable and preferred solvents are, for example, toluene, anisole, o-, m- or p-xylene, methyl benzoate, mesitylene, tetralin, veratrole, THF, methyl-THF, THP, chlorobenzene, dioxane, phenoxytoluene, especially 3-phenoxytoluene, (-)-fencon, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole, 2-phenoxyethanol, 2-pyrrolidinone, 3-methylanisole, 4-methylanisole, 3,4-dimethylanisole, 3,5-dimethylanisole, acetophenone, α-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, cyclohexylbenzene, decalin, dodecylbenzene, ethyl benzoate, indane, NMP, p-cymene, phenetole, 1,4-diisopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene, octylbenzene, 1,1-bis(3,4-dimethylphenyl)ethane, hexamethylindane, 2-methylbiphenyl, 1-methylnaphthalene, 1-ethylnaphthalene, ethyl octanoate, diethyl sebacate, octyl octanoate, heptylbenzene, methyl isovalerate, cyclohexyl hexanoate, or mixtures of these solvents.

[0154] Furthermore, the present invention relates to a formulation comprising at least one compound of the present invention and at least one further compound. The further compound may be a solvent, in particular one of the above-mentioned solvents or a mixture of those solvents. The further compound may also be an organic or inorganic compound, such as a matrix material, which is likewise used in electronic devices. This further compound may be a polymer.

[0155] The above-mentioned compound of the present invention may be used as an active ingredient in an electronic device, preferably as a light emitter in a light-emitting layer, or as a hole or electron transport material in a hole or electron transport layer, or as an oxygen sensitizer, or as a photoinitiator or photocatalyst. Thus, the present invention further provides for the use of a compound according to the present invention in an electronic device or as an oxygen sensitizer, or as a photoinitiator or photocatalyst. The enantiomerically pure iridium complex according to the present invention is suitable as a photocatalyst for chiral photoinduced synthesis.

[0156] The present invention further provides an electronic device comprising at least one compound of the present invention.

[0157] An electronic element is understood to mean any element comprising an anode, a cathode and at least one layer (this layer comprising at least one organic or organometallic compound). Thus, the electronic element according to the invention comprises an anode, a cathode and at least one layer comprising at least one iridium complex according to the invention. Preferred electronic elements are organic electroluminescence elements (OLED, PLED), organic integrated circuits (O-IC), organic field effect transistors (O-FET), organic thin film transistors (O-TFT), organic light emitting transistors (O-LET), organic solar cells (O-SC), where the latter is understood to mean both pure organic solar cells and dye-sensitized solar cells, organic optical detectors, organic photoreceptors, organic field quenching devices (O-FQD), light emitting electrochemiluminescent cells (LEC), oxygen sensors and organic laser diodes (O-laser), which are selected from the group consisting of: Compounds that emit light in the infrared are suitable for use in organic infrared electroluminescence elements and infrared sensors. Particularly preferred is an organic electroluminescence element. The active ingredient is usually an organic or inorganic material introduced between the anode and the cathode, such as a charge injection, charge transport or charge blocking material, in particular a light emitting material and a matrix material. The compounds of the invention exhibit particularly good properties as light emitting materials in organic electroluminescence elements. A preferred embodiment of the invention is therefore an organic electroluminescence element. Furthermore, the compounds of the invention are used for the generation of singlet oxygen or in photocatalytic reactions.

[0158] The organic electroluminescent element comprises a cathode, an anode, and at least one light-emitting layer. Separately from these layers, there may be further layers, for example, in each case, one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, exciton blocking layers, electron blocking layers, charge generation layers, and / or organic or inorganic p / n junctions. In this case, one or more hole transport layers can be p-doped by, for example, metal oxides such as MoO3 or WO3, or (per)fluorinated electron-deficient aromatics, or electron-deficient cyano-substituted heteroaromatics (e.g., according to JP4747558, JP2006-135145, US2006 / 0289882, WO2012 / 095143), or quinoid systems (e.g., according to EP1336208), or Lewis acids, or boranes (e.g., according to US2003 / 0006411, WO2002 / 051850, WO2015 / 049030), carboxylates of group III, IV, or V main group metals, and / or one or more electron transport layers can be n-doped.

[0159] Similarly, an intermediate layer, for example, having an exciton blocking function, and / or controlling charge balance in the electroluminescent element, and / or generating charges (charge generation layer, for example, in a layer system having two or more light-emitting layers, for example, in a white light-emitting OLED component), may be introduced between two light-emitting layers. However, it should be noted that each of these layers does not necessarily have to be present.

[0160] In this case, the organic electroluminescence element may include one light-emitting layer or a plurality of light-emitting layers. When a plurality of light-emitting layers are present, these preferably have a plurality of emission maxima over the entire range of 380 nm to 750 nm, and as a result, various light-emitting compounds that emit white light as a whole, that is, can emit fluorescence or phosphorescence, are used in the light-emitting layer. Particularly preferred embodiments are a three-layer system in which three layers exhibit blue, green, and orange or red emission (for the basic structure, see, for example, WO2005 / 011013), or a system having more than three light-emitting layers. This system may be a hybrid system in which one or more layers emit fluorescence and one or more layers emit phosphorescence. A preferred form is a tandem OLED. The white-light-emitting organic electroluminescence element may be used for lighting applications or together with color filters of a full-color display.

[0161] In a preferred form of the present invention, the organic electroluminescence element comprises the iridium complex of the present invention as a light-emitting compound in one or more light-emitting layers.

[0162] When the iridium complex according to the present invention is used as a light-emitting compound in the light-emitting layer, it is preferably used in combination with one or more matrix materials. The mixture of the iridium complex according to the present invention and the matrix material contains 0.1% to 99% by volume, preferably 1% to 90% by volume, more preferably 3% to 40% by volume, particularly 5% to 15% by volume, of the iridium complex according to the present invention with respect to the entire mixture of the phosphor and the matrix material. Correspondingly, the mixture contains 99.9% to 1% by volume, preferably 99% to 10% by volume, more preferably 97% to 60% by volume, particularly 95% to 85% by volume, of the matrix material with respect to the entire mixture of the phosphor and the matrix material.

[0163] Suitable matrix materials for the compounds of the present invention are ketones, phosphine oxides, sulfoxides, and sulfones (e.g., according to WO2004 / 013080, WO2004 / 093207, WO2006 / 005627 or WO2010 / 006680), triarylamines, carbazole derivatives (e.g., CBP (N,N-biscarbazonylbiphenyl), m-CBP or carbazole derivatives disclosed in WO2005 / 039246, US2005 / 0069729, JP2004 / 288381, EP1205527, WO2008 / 086851 or US2009 / 0134784), crosslinked carbazole derivatives (e.g., according to US2009 / 0136779, WO2010 / 050778, WO2011 / 042107 or WO2011 / 088877), biscarbazole derivatives, indolocarbazole derivatives (e.g., according to WO2007 / 063754 or WO2008 / 056746), indenocarbazole derivatives (e.g., according to WO2010 / 136109 or WO2011 / 000455), azacarbazole (e.g., according to EP1617710, EP1617711, EP1731584, JP2005 / 347160), bipolar matrix materials (e.g., according to WO2007 / 137725), silanes (e.g., according to WO2005 / 111172), azaborole or boronic acid esters (e.g., according to WO2006 / 117052), diazasilole derivatives (e.g., according to WO2010 / 054729), diazaphosphole derivatives (e.g., according to WO2010 / 054730), triazine derivatives (e.g., according to WO2010 / 015306, or WO2007 / 063754, or WO2008 / 056746), zinc complexes (e.g., according to EP652273 or WO2009 / 062578), dibenzofuran derivatives (e.g., according to WO2009 / 148015), dibenzothiophene derivatives or triphenylene derivatives.

[0164] It is also preferable to use a plurality of different matrix materials as a mixture, in particular at least one electron-conductive matrix material and at least one hole-conductive matrix material. Preferred combinations are, for example, using an aromatic ketone, a triazine derivative or a phosphine oxide derivative as a mixed matrix of the metal complex according to the present invention together with a triarylamine derivative or a carbazole derivative. Similarly, the use of a mixture of a charge transport matrix material and an electrically inert matrix material (for example, as disclosed in WO2010 / 108579) that has no obvious involvement even if there is any in charge transport is also preferable.

[0165] Preferred biscarbazoles that can be used as matrix materials for the compounds of the present invention have the structures of the following formulas (31) and (32).

Chemical formula

[0166] Preferred forms of the compounds of formulas (31) and (32) are the compounds of the following formulas (31a) and (32a).

Chemical formula

[0167] Examples of suitable compounds of formulas (31) and (32) are the compounds described below.

Chemical formula

[0168] The preferred dibenzofuran derivative is a compound of the following formula (33). [Chemical formula] Here, oxygen may be replaced by sulfur to form dibenzothiophene, L is a single bond or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms and may be substituted by one or more R radicals, and R and Ar 1 have the meanings described above. Here, two Ar 1 groups bonded to the same nitrogen atom, or one Ar 1 group and one L group bonded to the same nitrogen atom may be bonded to each other to form, for example, carbazole.

[0169] The preferred carbazole amine has the structures of the following formulas (34), (35) and (36). [Chemical formula] Here, L is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms and may be substituted by one or more R radicals, and R and Ar 1 have the meanings described above.

[0170] Preferred triazine, quinazoline, or pyrimidine derivatives that can be used as a mixture with the compounds of the present invention are compounds of the following formulas (37), (38) and (39). [Chemical formula] Here, Ar 1 and R have the meanings described above.

[0171] Particularly preferred are the triazine derivatives of formula (37) and the quinazoline derivatives of formula (39), especially the triazine derivatives of formula (37).

[0172] In a preferred form of the present invention, Ar in formulas (37), (38) and (39) 1 is, each time it appears, the same or different and is an aromatic or heteroaromatic ring system having 6 to 30 aromatic ring atoms, particularly 6 to 24 aromatic ring atoms, which may be substituted by one or more R radicals. Here, preferred aromatic or heteroaromatic ring systems Ar 1 are in the form of Ar 1 Ar 2 and Ar 3 and are the same as those defined above, particularly in the structures of Ar-1 to Ar-76.

[0173] Examples of suitable triazine compounds that may be used as matrix materials together with the compounds of the present invention are the compounds listed in the following table.

Chemical formula

Chemical formula

Chemical formula

[0174] It is more preferable that a mixture of two or more triplet emitters, particularly two or three triplet emitters, is used together with one or more matrix materials. In this case, a triplet emitter having a shorter emission wavelength spectrum functions as a co-matrix of a triplet emitter having a longer emission wavelength spectrum. For example, the metal complex of the present invention can be combined as a co-matrix with a metal complex that emits shorter wavelengths, such as a blue, green or yellow-emitting metal complex. For example, the metal complex of the present invention can also be used as a co-matrix for a triplet emitter that emits longer wavelengths, such as a red-emitting triplet emitter. In this case, it is also preferable that both the metal complexes emitting shorter and longer wavelengths are compounds of the present invention. A preferred form in the case of using a mixture of three triplet emitters is when two are used as co-hosts and one is used as an emitter material. These triplet emitters preferably emit light in green, yellow and red, or blue, green and orange colors.

[0175] A preferred mixture in the light-emitting layer comprises an electron-transporting host material, a so-called "wide band gap" host material (which, due to its electronic properties, is not or only insignificantly involved in charge transport in the layer), a co-dopant (which is a triplet emitter that emits at a shorter wavelength than the compound according to the present invention), and a compound of the present invention.

[0176] A further preferred mixture in the light-emitting layer comprises an electron-transporting host material, a so-called "wide band gap" host material (which, due to its electronic properties, is not or only insignificantly involved in charge transport in the layer), a hole-transporting host material, a co-dopant (which is a triplet emitter that emits at a shorter wavelength than the compound according to the present invention), and a compound of the present invention.

[0177] The compounds of the present invention can be used for other functions in electronic devices. For example, they can be used as a hole transport material in a hole injection or transport layer, as a charge generation material, as an electron blocking material, as a hole blocking material, or as an electron transport material, for example, in an electron transport layer. Similarly, it is also possible to use the compounds of the present invention as a matrix material for other phosphorescent metal complexes in a light-emitting layer.

[0178] The cathode preferably comprises a metal, metal alloy or multilayer structure having a low work function, comprising various metals such as alkaline earth metals, alkali metals, main group metals or lanthanoids (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Further, suitable is an alloy comprising an alkali metal or alkaline earth metal and silver (e.g., an alloy comprising magnesium and silver). In the case of a multilayer structure, a further metal having a relatively high work function, e.g., Ag, may also be used in addition to the said metal, in which case combinations of metals such as, for example, Mg / Ag, Ca / Ag or Ba / Ag are generally used. It may also be preferable to introduce a thin intermediate layer made of a material having a high dielectric constant between the metal cathode and the organic semiconductor. Examples of materials that can be used for this purpose are fluorides of alkali metals or alkaline earth metals, but corresponding oxides or carbonates (e.g., LiF, Li2O, BaF2, MgO, NaF, CsF, Cs2CO3, etc.). Similarly, an organic alkali metal complex, e.g., Liq (lithium quinolate), can be used for this purpose. The layer thickness of this layer is preferably 0.5 to 5 nm.

[0179] A preferred anode is a material with a high work function. Preferably, the anode has a work function greater than 4.5 eV with respect to vacuum. First, metals with a high redox potential are suitable for this purpose. For example, Ag, Pt, or Au. Next, metal / metal oxide electrodes (e.g., Al / Ni / NiOx, Al / PtOx) are also preferred. In some applications, at least one electrode should be transparent or partially transparent. This is to enable the emission or luminescence of organic materials (O-SC) (OLED / PLED, O-laser). Here, a preferred anode material is a highly conductive mixed metal oxide. Particularly preferred is indium tin oxide (ITO) or indium zinc oxide (IZO). Further, preferably, conductive doped organic materials, particularly conductive doped polymers such as PEDOT, PANI, or derivatives of these polymers, are mentioned. More preferably, when a p-doped hole transport material is applied to the anode as hole injection, suitable p-dopants are metal oxides such as MoO3 or WO3 or (per)fluorinated electron-deficient aromatic systems. Even more suitable p-dopants are HAT-CN (hexacyanohexaazatriphenylene) or the compound NPD9 manufactured by Novaled. Such a layer simplifies hole injection in materials with a low HOMO, i.e., a large HOMO value.

[0180] Any material used in a layer in the prior art can generally be used in a further layer. A person skilled in the art would be able to combine each material with the materials according to the invention in an electronic device without inventive step.

[0181] Suitable charge transport materials that can be used in the hole injection or hole transport layer, electron blocking layer, or electron transport layer of the organic electroluminescence device according to the present invention are, for example, the compounds disclosed in Y. Shirota et al., Chem. Rev. 2007, 107(4), 953-1010, or other materials used in these layers of the prior art. Preferred hole transport materials in the hole transport, hole injection, or electron transport layer in the electroluminescence device of the present invention are indenofluoreneamine derivatives (for example, WO06 / 122630 or WO06 / 100896), amine derivatives disclosed in EP1661888, hexaazatriphenylene derivatives (for example, WO01 / 049806), amine derivatives containing condensed aromatic rings (for example, US5,061,569), amine derivatives disclosed in WO95 / 09147, monobenzylindeno[1,2-b]fluoreneamine (for example, WO08 / 006449), dibenzylindeno[1,2-b]fluoreneamine (for example, WO07 / 140847), spirobifluoreneamine (for example, WO2012 / 034627, WO2014 / 056565), fluoreneamine (for example, EP2875092, EP2875699, and EP2875004), spirobivenzopyranamine (for example, EP2780325), and dihydroacridine derivatives (for example, WO2012 / 150001).

[0182] The device is accordingly structured, connected, and finally sealed (depending on the application). This is because the lifetime of such a device is dramatically shortened in the presence of water and / or air.

[0183] More preferably, it is an organic electroluminescence device in which one or more layers are applied by sublimation. In this case, the material is typically applied by vapor deposition in a vacuum sublimation system at an initial pressure of less than 10 -5 mbar, preferably less than 10 -6 mbar. The initial pressure can be lower or higher, for example, less than 10 -7 mbar.

[0184] Similarly, an organic electroluminescence device, characterized in that one or more layers are applied by means of an OVPD (organic vapor deposition) method or by means of carrier gas sublimation, is also preferred. In this case, the material is applied at a pressure of 10 -5 mbar to 1 bar. A special method of this process is the OVJP (organic vapor jet printing) method, the material of which is applied directly via a nozzle and is thus structured (e.g. M.S. Arnold et al., Appl. Phys. Lett. 2008, 92, 053301).

[0185] Furthermore, an organic electroluminescence device, characterized in that one or more layers are produced from a solution, for example by spin coating or by means of any printing method, such as screen printing, flexographic printing, offset printing or nozzle printing, particularly preferably by LITI (light-induced thermal imaging, thermal transfer printing) or inkjet printing, is preferred. For this purpose, soluble compounds are required, which can be obtained, for example, via suitable substitutions.

[0186] The organic electroluminescence device can also be produced as a hybrid system by applying one or more layers from a solution and applying one or more other layers by vapor deposition. For example, a light-emitting layer comprising a metal complex and a matrix material according to the invention can be applied from a solution, and a hole-blocking layer and / or an electron transport layer can be applied by vapor deposition under reduced pressure.

[0187] These methods are generally known to those skilled in the art, and those skilled in the art can apply them to the organic electroluminescence device comprising the compound of formula (I) or the preferred forms described above without difficulty.

[0188] The electronic device of the present invention, particularly the organic electroluminescence device, has high efficiency, good lifetime and low operating voltage. Furthermore, the compounds of the present invention are very thermally stable, and in particular, compounds with a molecular weight that is not too high, in particular a molecular weight of about 1200 g / mol, can be sublimated efficiently without decomposition.

[0189] These above-mentioned advantages do not involve the deterioration of other electrical characteristics.

[0190] The present invention will be illustrated in more detail by way of examples hereinafter, but is not intended to be limited thereby. Those skilled in the art will be able to manufacture further electronic elements according to the present invention using the described details without making inventive efforts, and thereby implement the present invention over the entire scope claimed.

[0191] Description of the Drawings FIG. 1 shows the X-ray structure of the complex Ir617 of the present invention, and its synthesis is described in the following examples.

[0192] Examples: The following syntheses are carried out in a dry solvent under a protective gas atmosphere unless otherwise specified. The metal complexes are further handled by excluding light or under yellow light. Solvents and reagents can be purchased, for example, from sigma-ALDRICH or ABCR. Each number within square brackets or the numbers shown for individual compounds relates to the CAS number of the compound known from the literature. In the case of compounds that can have multiple tautomeric, isomeric, enantiomeric, or diastereomeric forms, one form is shown in a representative manner.

[0193] A: Synthesis of synthon S: Example S1: [Chemical formula] To a mixture of 18.2 g (50 mmol) of 2,2'-(5-chloro-1,3-phenylene)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] [1417036-49-7], 28.3 g (100 mmol) of 1-bromo-2-iodobenzene, 31.8 g (300 mmol) of sodium carbonate, 200 ml of toluene, 100 ml of ethanol and 200 ml of water, 788 g (3 mmol) of triphenylphosphine and 225 mg (1 mmol) of palladium(II) acetate are added with good stirring, and the mixture is heated under reflux for 48 hours. After cooling, the organic phase is removed, washed once with 300 ml of water and once with 300 ml of saturated sodium chloride solution, and dried over magnesium sulfate. The drying agent is filtered off and the filtrate is concentrated completely under reduced pressure. The residue is flash chromatographed (Tronaut automatic column system by A. Semrau). Yield: 16.5 g (39 mmol), 78%; Purity: about 97% 1 By 1H NMR.

[0194] Example S2:

Chemical formula

[0195] Stage S2a:

Chemical formula

[0196] Stage S2b: [Chemical formula] A well-stirred mixture of 26.6 g (100 mmol) of S2a, 15.6 g (100 mmol) of 4-chlorophenylboronic acid [1679-18-1], 27.6 g (200 mmol) of potassium carbonate, 702 mg (1 mmol) of bis(triphenylphosphine)palladium(II) chloride, 50 g of glass beads (3 mmol in diameter), 200 ml of acetonitrile and 100 ml of methanol is heated under reflux for 16 h. After cooling, the precipitated solid is suction filtered, washed three times with 100 ml of water each and twice with 50 ml of methanol, and dried under reduced pressure. The solid is dissolved in 500 ml of dichloromethane (DCM) and 100 ml of ethyl acetate (EA) and filtered through a silica gel bed in the form of a DCM slurry. The filtrate is concentrated under reduced pressure. The residual solid is extracted by stirring with 150 ml of hot ethanol, suction filtered and dried under reduced pressure. Yield: 27.3 g (80 mmol), 80%; Purity: about 97% 1 By 1H NMR.

[0197] Stage S2c: [Chemical formula] To a mixture of 34.2 g (100 mmol) of S2b, 26.7 g (105 mmol) of bis(pinacolato)diboron, 29.4 g (300 mmol) of potassium acetate (anhydrous), 50 g of glass beads (3 mm in diameter), and 500 ml of THF, 821 mg (2 mmol) of S-Phos and 225 mg (1 mmol) of palladium(II) acetate were added with good stirring, and the mixture was heated under reflux for 16 hours. While the mixture was still warm, the salts and glass beads were suction filtered through a bed of celite in THF slurry form, which was washed with a little THF, and the filtrate was concentrated to dryness. The residue was taken up in 100 ml of MeOH, stirred in the warm solvent, the crystallized product was suction filtered, washed twice with 30 ml of methanol each, and dried under reduced pressure. Yield: 36.4 g (84 mmol), 84%; Purity: about 95% 1 By H-NMR.

[0198] Stage S2: To a well-stirred mixture of 21.3 g (100 mmol) of S2c, 13.6 g (100 mmol) of 1-bromo-2-iodobenzene [583-55-1], 53.0 g (500 mmol) of sodium carbonate, 400 ml of toluene, 200 ml of ethanol, and 400 ml of water, 1.57 g (6 mmol) of triphenylphosphine and 449 mg (2 mmol) of palladium(II) acetate were added, and the mixture was heated under reflux for 16 hours. After cooling, the organic phase was removed, washed twice with 200 ml of water each and once with 200 ml of saturated sodium chloride solution, and dried over magnesium sulfate. The filtrate was filtered through a bed of celite in toluene slurry form, concentrated to dryness, and the residue was recrystallized from about 50 ml of methanol by the addition of a small amount of ethyl acetate. Yield: 37.4 g (83 mmol), 83%; Purity: about 95% 1 By H NMR.

[0199] The following compounds can be prepared similarly.

Chemical formula

[0200] Example S20:

Chem.

[0201] Stage S20a:

Chem.

[0202] Stage S20b:

Chem.

[0203] Stage S20: To a well-stirred mixture of 34.2 g (100 mmol) of S20b, 17.2 g (110 mmol) of 2-chlorophenylboronic acid [3900-89-8], 41.5 g (300 mmol) of potassium carbonate, 600 ml of THF and 200 ml of water were added 1.64 g (4 mmol) of S-Phos and 499 mg (2 mmol) of palladium(II) acetate, and the mixture was heated under gentle reflux for 16 h. After cooling, the organic phase was removed, washed twice with 200 ml of saturated sodium chloride solution each, and concentrated to dryness. The residue was boiled in 100 ml of ethanol for 4 h. After cooling, the solid was suction filtered, washed with 50 ml of ethanol and dried. Further purification was carried out by recrystallization from about 200 ml of ethyl acetate. Yield: 25.9 g (62 mmol), 62%; Purity: about 95% 1 By 1H NMR.

[0204] The following compounds can be prepared similarly.

Chemical formula

Chemical formula

Chemical formula

[0205] Example S50:

Chemical formula

[0206] The following compounds can be prepared in the same manner.

Chemical formula

Chemical formula

[0207] Example S100:

Chemical formula

[0208] The following compounds can be prepared similarly.

Chemical formula

[0209] Example S200:

Chemical formula

[0210] The following compounds can be prepared similarly. [Chemical formula] [Chemical formula]

[0211] Example S400: [Chemical formula] A well-stirred mixture of 50.8 g (100 mmol) of S200, 31.4 g (120 mmol) of triisopropylsilylethynyl bromide [111409-79-1], 26.5 g (250 mmol) of sodium carbonate, 2.31 g (2 mmol) of tetrakis(triphenylphosphine)palladium(0), 600 ml of toluene, 300 ml of ethanol and 100 ml of water is stirred at 80 °C for 24 h. After cooling, the organic phase is removed, washed twice with 200 ml of saturated sodium chloride solution each time, and dried over magnesium sulfate. The drying agent is filtered off, the filtrate is concentrated under reduced pressure at 30 °C, the residue is taken up in 500 ml of dichloromethane, 110 ml of TBAF (1 M in THF) [10549-76-5] is added, the mixture is stirred for an additional 1 h, and washed twice with 300 ml of water each time, washed twice with 200 ml of saturated sodium chloride solution each time, concentrated at 30 °C, and the residue is chromatographed using an automated column system (CombiFlash Rf by A Semrau). Storage of the product in the freezer. Yield: 29.4 g (72 mmol), 72%; Purity: about 97% 1 By 1H NMR.

[0212] The following compounds can be prepared similarly. [Chemical formula]

[0213] B: Synthesis of ligand L: Example L1: [Chemical formula] To a mixture of 50.9 g (100 mmol) of S200, 31.0 g (100 mmol) of 2-(2'-bromo[1,1'-biphenyl]-4-yl)pyridine [1374202-353], 63.7 g (300 mmol) of tripotassium phosphate, 400 ml of toluene, 200 ml of dioxane and 400 ml of water, 1.64 g (4 mmol) of S-Phos and 449 mg (2 mmol) of palladium(II) acetate are added with good stirring, and the mixture is heated under reflux for 24 hours. After cooling, the organic phase is removed and washed twice with 300 ml of water each time and once with 300 ml of saturated sodium chloride solution, and then dried over magnesium sulfate. The desiccant is filtered off, the filtrate is concentrated and dried under reduced pressure, and the glassy crude product is recrystallized twice from acetonitrile (~150 ml) and then from acetonitrile / ethyl acetate by boiling. Yield: 43.3 g (71 mmol), 71%; Purity: about 95% 1 By 1H NMR.

[0214] The following compounds can be prepared similarly.

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0215] Example L200:

Chemical formula

[0216] The following compounds can be prepared similarly.

Chemical formula

Chemical formula

[0217] C: Synthesis of complex: C1: Uncharged monodentate Co ligand Example Ir100:

Chem.

[0218] The following compounds can be prepared similarly.

Chem.

Chem.

Chem.

[0219] C2: Monoanionic monodentate Co ligand Example Ir200:

Chem.

[0220] The following compounds are obtained analogously.

Chemical formula

[0221] C3: Monoanionic and charge - free monodentate Co ligand Example Ir300:

Chemical formula

[0222] C4: A neutral bidentate Co ligand Example Ir400: [Chemical formula] A mixture of 7.64 g (10 mmol) of L2, 4.15 g (10 mmol) of [(1,2,5,6 - η)-1,5 - cyclooctadiene][(1,2,3,3a,7a - η)-1H - inden - 1 - yl]iridium(=(Ind)Ir(COD))[102525 - 11 - 1], 100 ml of glacial acetic acid and 100 ml of dioxane is stirred at 100 °C for 24 h. The red solution is concentrated to dryness, the residue is taken up in 100 ml of DCM, 5 ml of triarylamine, and 1.87 g (12 mmol) of 2,2'-bipyridine [366 - 18 - 7] are added, and the mixture is stirred for a further 12 h. Then the DCM is distilled off and the distilled DCM is continuously replaced by methanol. Finally, the mixture is concentrated to a volume of about 50 ml under reduced pressure, the product is suction filtered, washed three times with 30 ml of methanol each, and dried under reduced pressure. Purification is carried out by two chromatography runs on silica gel using DCM / EA (2:1, v / v). The product thus obtained can be further carried out by thermal extraction and heat treatment or fractional sublimation as disclosed in WO2016 / 124304. Yield: 3.67 g (3.3 mmol); 33% of theory; Purity: >99.5% 1 By 1H NMR.

[0223] C5: A monoanionic bidentate Co ligand Example Ir500: [Chemical formula] A mixture of 8.21 g (10 mmol) of L13, 3.53 g (10 mmol) of IrCl3·3H2O [13569-57-8], 150 ml of ethoxyethanol and 50 ml of water is heated under reflux for 24 h. The brown suspension is concentrated to dryness, and the residue is taken up in 100 ml of 2-ethoxyethanol. 7.76 g (50 mmol) of 2-phenylpyridine [1008-89-5] and 7.71 g (30 mmol) of silver trifluoromethanesulfonate [2923-28-6] are added, and the mixture is stirred at 130 °C for 16 h. The solvent is removed under reduced pressure, the residue is taken up in 300 ml of DCM, filtered through a bed of celite in DCM slurry form, the DCM is distilled off and replaced continuously with methanol. Finally, the mixture is concentrated to about 100 ml, the precipitated product is filtered off with suction, washed three times with 30 ml of methanol each time and dried under reduced pressure. Purification is carried out by two chromatography runs on silica gel using toluene / DCM (9:1, v / v). The product thus obtained is purified by hot extraction and heat treatment or fractional sublimation as disclosed in WO2016 / 124304. Yield: Ir500a, diastereomer 1: 2.50 g (2.1 mmol); Ir500b, diastereomer 2: 2.24 g (1.9 mmol); Purity: >99.5% 1 By 1H NMR.

[0224] C6: Dianionic bidentate Co ligand Example Ir600:

Chemical formula

[0225] The following compounds can be prepared similarly.

Chemical Structure

[0226] Example: Manufacture of OLED 1) Vacuum-treated element: The OLEDs according to the present invention and the OLEDs according to the prior art are manufactured by the general method described in WO2004 / 058911, adapted to the circumstances (layer thickness range, materials used) described herein.

[0227] In the following examples, results for various OLEDs are shown. Cleaned glass plates (cleaned with a glass washer from Miele laboratory, detergent Extran from Merck) coated with 50 nm thick structured ITO (indium tin oxide) are pretreated with UV ozone for 25 minutes (PR-100 UV ozone generator from UVP), and within 30 minutes, for process improvement, coated with 20 nm of PEDOT:PSS (poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate), which is purchased from Heraeus Precious Metals GmbH (Germany) as CLEVIOS™ P VP AI 4083 and spin-coated from an aqueous solution), and baked at 180 °C for 10 minutes. These coated glass plates form the substrates on which the OLEDs are applied. The OLED basically has the following layer structure: substrate / hole injection layer 1 (HIL1) consisting of HTM1 doped with 5% NDP-9 (commercially available from Novaled), hole transport layer 1 (HTL1) consisting of 20 nm / HTM1, 150 nm for blue devices, 215 nm for green / yellow devices, 110 nm for red devices / hole transport layer 2 (HTL2) / emission layer (EML) / hole blocking layer (HBL) / electron transport layer (ETL) / and finally the cathode. The cathode is formed by an aluminum layer with a thickness of 100 nm.

[0228] First, a vacuum-processed OLED will be described. For this purpose, all materials are applied by thermal evaporation in a vacuum chamber. Here, the light-emitting layer always consists of at least one matrix material (host material) and a light-emitting dopant (luminescent substance) that is mixed with the matrix material in a specific volume ratio by co-evaporation. Here, details shown in the form of M1:M2:Ir(L1)(55%:35%:10%) mean that material M3 is present in that layer at a volume ratio of 55%, M2 is present in that layer at a volume ratio of 35%, and Ir(L1)3 is present in that layer at a ratio of 10%. Similarly, the electron transport layer may also consist of a mixture of two materials. The exact structure of the OLED is shown in Table 1. The materials used in the manufacture of the OLED are shown in Table 4.

[0229] The OLEDs are characterized by standard methods. For this purpose, the electroluminescence spectrum, current efficiency (measured in cd / A), power efficiency (measured in lm / W), and external quantum efficiency (EQE, measured in percent) as a function of luminous flux density are calculated from the current / voltage / current density characteristic curve (IUL characteristic curve) assuming Lambertian emission characteristics, and the lifetime is determined. The electroluminescence spectrum is determined at a luminous flux density of 1000 cd / m 2 and the CIE 1931 x and y color coordinates are then calculated from this. The OLEDs can initially also be operated at different initial luminances. The lifetime values can be converted to numerical values for other initial luminances using conversion formulas known to those skilled in the art.

[0230] Use of the compounds of the present invention as light-emitting materials in phosphorescent OLEDs One use of the compounds of the present invention is as a phosphorescent light-emitting material in the light-emitting layer in an OLED. The results of the OLEDs are summarized in Table 2.

[0231] [Table 1] [Table 2]

[0232] Solution-treated element: A: From a low molecular weight soluble functional material The iridium complex of the present invention can also be processed from a solution, in which case, while having good characteristics, it results in an OLED that is very simple in terms of processing technology compared to a vacuum-processed OLED. The production of such components is based on the production of polymer light-emitting diodes (PLEDs) that have been described several times in the literature (for example, WO2004 / 037887). Its structure is composed of a substrate / ITO / hole injection layer (60 nm) / intermediate layer (20 nm) / light-emitting layer (60 nm) / hole-blocking layer (10 nm) / electron transport layer (40 nm) / cathode. For this purpose, a substrate (soda-lime glass) manufactured by Technoprint is used, to which an ITO structure (indium tin oxide, transparent conductive anode) is applied. The substrate is cleaned in a clean room using DI water and a detergent (Deconex 15PF), and then activated by UV / ozone plasma treatment. Subsequently, also in the clean room, a 20-nm hole injection layer (PEDOT:PSS Clevios (trademark)) is applied by spin coating. The required spin speed depends on the dilution and the shape of a specific spin coater. To remove residual water from the layer, the substrate is baked on a hot plate at 200 °C for 30 minutes. The intermediate layer used functions for hole transport. In this case, Merck's HL-X is used. The intermediate layer can be replaced with one or more layers as long as it satisfies the condition of not being desorbed again by the subsequent processing step of EML deposition from a solution. For the production of the light-emitting layer, the triplet emitter of the present invention is dissolved in toluene or chlorobenzene together with a matrix material. Here, when a typical layer thickness of 60 nm for the device is achieved by spin coating, the typical solid content of the solution is 16 - 25 g / l. The solution-processed devices include a light-emitting layer composed of M5:M6:IrL (20%:55%:25%). That is, they contain two different Ir complexes. The percentage values in the case of materials processed from a solution mean weight %. The light-emitting layer is applied by spin coating in an inert gas atmosphere, in the case of the present invention, in argon, and heated at 160 °C for 10 minutes.On top of the latter, a hole-blocking layer (10 nm ETM1) and an electron transport layer (40 nm ETM1(50%) / ETM2(50%)) are deposited (e.g., a deposition apparatus made by Lesker, typical deposition pressure is 5×10. -6 mbar). Finally, a cathode of aluminum (100 nm) is applied by deposition (high-purity metal is made by Aldrich). To protect the device from air and atmospheric moisture, the device is finally encapsulated and then its characteristics are determined. Examples of OLEDs are not yet optimized. The results obtained are summarized in Table 3.

Table 3

Table 4-1

Table 4-2

Brief Description of the Drawings

[0233]

Figure 1

Claims

1. A compound of formula (1). 【Chemical 1】 (wherein the symbols and subscripts used are as follows: L １ is a bidentate ancillary ligand that coordinates to iridium via one carbon atom and one nitrogen atom, or via two carbon atoms; L ２ and L ３ is the same or different each time it appears and is selected from an aryl or heteroaryl group having 5 to 14 aromatic ring atoms or a heteroalicyclic group having 5 to 7 ring atoms, each of which coordinates to iridium via a carbon atom or a nitrogen atom, each of which is part of an aryl or heteroaryl group or a heteroalicyclic group, and which may be substituted by one or more R radicals; L ４ is a bidentate ligand or, if the same or different for each occurrence, is a monodentate ligand; a is 1 when L ４ is a bidentate ligand, and a is 2 when L ４ is a monodentate ligand; V is a group of formula (2) 【Chemical Formula 2】 Here, the dotted-line connections each indicate the positions of the bonds to the ligands L １ , L ２ and L ３ and, furthermore: A is the same or different each time it appears, and is CR ２ -CR ２ or a group of the following formula (4) 【Chemical Formula 3】 Here, in each case, the dotted line connection indicates the position of the connection to the ligand L １ , L ２ or L ３ , and indicates the position of the connection of the unit of formula (4) to the central trivalent aryl of formula (2); ＊ ​ X １ is CR; X ２ is CR; X ３ is C; R is H; L １ is coordinated to iridium through two positions marked with ＊ and is selected from the structures of formulas (L １ -1-1) to (L １ -1-3) and (L １ -2-1) to (L １ -2-5). 【Chemical Formula 4】 (wherein X is the same or different at each occurrence and is CR or N, and "o" indicates the position of the bond to bridge V) or L １ is ＊ coordinated to iridium by two positions marked by (L １ -39) or (L １ -40) selected from the structures [Chemical Formula 5] (wherein "o" indicates the position of the bond to bridge V, and further: X is the same or different at each occurrence and is CR or N; Z is CR', CR or N, provided that exactly one Z is CR' and the other Zs are CR or N; wherein a maximum of one symbol X or Z per ring is N; R' is a group of formula (16) or (17) below: 【Chemical Formula 6】 Here, the dotted-line bond indicates the bonding of this group to the ligand of formula (L １ -39) or (L １ -40); R″ is the same or different for each occurrence and is H, D, F, CN, a linear alkyl group having 1 to 10 carbon atoms (where one or more hydrogen atoms may be replaced by D or F), a branched or cyclic alkyl group having 3 to 10 carbon atoms (where one or more hydrogen atoms may be replaced by D or F), or an alkenyl group having 2 to 10 carbon atoms (where one or more hydrogen atoms may be replaced by D or F); simultaneously, two adjacent R″ radicals or the two R″ radicals of adjacent phenyl groups may together form a ring system; or the two R″ of adjacent phenyl groups are together a group selected from C(R １ ), NR ２ １ , O or S, and the two phenyl rings together with the bridging group are carbazole, fluorene, dibenzofuran or dibenzothiophene, and further R″ is as defined above;​ n is 0, 1, 2, 3, 4 or 5), L ２ and L ３ are the same or different for each occurrence, and the formula (L ２ −1) / (L ３ −1) to (L ２ −55) / (L ３ −55) is selected from the structure (where this group is itself Each ＊ and coordinates to the bridgehead V at the position marked with an "o"); 【Chemical Formula 7-1】 【Chemical Formula 7-2】 【Chemical Formula 7-3】 (wherein R has the above meaning and the other symbols are as follows: X is the same or different at each occurrence and is CR or N, provided that a maximum of two symbols X per ring are N; W is the same or different at each occurrence and is NR, O or S), a compound characterized thereby.

2. The compound according to claim 1, characterized in that the group of formula (2) is represented by formula (2a). 【Chemical 8】 (wherein the symbols have the meanings described in claim 1)

3. The compound according to claim 1 or 2, characterized in that the group of formula (4) is represented by formula (4'). 【Chemical Formula 9】 (Here, the symbols have the meanings described in claim 1, and X ２ are identical and are CR)

4. The compound according to any one of claims 1 to 3, characterized in that the group of formula (2) is selected from the groups of formula (2a-1) to (2d-1). 【Chemical Formula 10】 (wherein the symbols have the meanings described in claim 1)

5. Monodentate ligand L ４ is the same or different each time it appears and is selected from the group consisting of carbon monoxide, nitric oxide, alkyl cyanide, aryl cyanide, alkyl isocyanide, aryl isocyanide, amine, phosphine, phosphite, arsine, stibine, nitrogen-containing heterocycle, carbene, hydride, deuteride, fluoride, chloride, bromide, iodide, alkyl acetylide, aryl acetylide, cyanide, cyanate, isocyanate, thiocyanate, isothiocyanate, aliphatic or aromatic alkoxide, aliphatic or aromatic thioalkoxide, amide, carboxylate or aryl group, and the bidentate ligand L4 is diamine, imine, diimine, heterocycle containing two nitrogen atoms, diphosphine, 1,3-diketonate derived from 1,3-diketone, 3-ketonate derived from 3-ketoester, carboxylate derived from aminocarboxylic acid, salicylimine derived from salicylimine, dialkoxide derived from dialcohol, dithiolate derived from dithiol, bis(pyrazolylborate), bis(imidazolyl)borate, 3-(2-pyridyl)dia Selected from the group consisting of zole or 3-(2-pyridyl)triazole; Or, L ４ is one of the ligands of formula (L ４ -1), (L ４ -2) and (L ４ -3) 【Chemical 11】 (wherein the symbols used are as follows: CyC is the same or different at each occurrence and is a substituted or unsubstituted aryl or heteroaryl group having 5 to 14 aromatic ring atoms, which coordinates to the metal via a carbon atom and is bonded to CyD via a covalent bond; CyD is the same or different at each occurrence and is a substituted or unsubstituted heteroaryl group having 5 to 14 aromatic ring atoms, which coordinates to the metal via a nitrogen atom or a carbene carbon atom and is bonded to CyC via a covalent bond; At the same time, two or more arbitrary substituents may together form a ring system); Or, L ４ is one of the ligands of formulas (L ４ -19) to (L ４ -24) (where these ligands coordinate to iridium via two atoms each marked with ＊ ): 【Chemical Formula 12】 A compound according to any one of claims 1 to 4, characterized in that (wherein R has the meaning as defined in claim 1, X is the same or different at each occurrence and is CR or N, provided that no more than two Xs are N).

6. A formulation comprising at least one compound according to any one of claims 1 to 5, and at least one further compound and / or a solvent.

7. Use of a compound according to any one of claims 1 to 5 in an electronic device, or as an oxygen sensitizer, or as a photoinitiator, or as a photocatalyst.

8. An electronic device comprising at least one compound according to any one of claims 1 to 5.

9. An organic electroluminescence device according to claim 8, characterized in that a compound according to any one of claims 1 to 5 is used as a light emitter in a light-emitting layer in combination with one or more matrix materials selected from the group consisting of ketones, phosphine oxides, sulfoxides, sulfones, triarylamines, carbazole derivatives, biscarbazoles, crosslinked carbazole derivatives, indolocarbazole derivatives, indenocarbazole derivatives, azacarbazoles, bipolar matrix materials, azaboroles, boronic esters, diazasilole derivatives, diazaphosphole derivatives, triazine derivatives, zinc complexes, dibenzofuran derivatives, dibenzothiophene derivatives or triphenylene derivatives.

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