Mononuclear tripodal hexadentate iridium complexes for use in OLEDs

Description

[0001] The present invention relates to iridium complexes which are suitable for use in organic electroluminescent devices, in particular as emitters.

[0002] According to the state of the art, bis- and tris-ortho-metalated irdium complexes with aromatic ligands are primarily used as triplet emitters in phosphorescent organic electroluminescent devices (OLEDs), where the ligands are connected via a negatively charged carbon atom and a neutral nitrogen atom. Examples of such complexes are tris(phenylpyridyl)iridium(III) and derivatives thereof. Such complexes are also known with polypodal ligands, as described, for example, in US Pat. No. 7,332,232, WO 2016 / 124304, and WO 2019 / 158453. Although these complexes with polypodal ligands exhibit advantages over complexes that otherwise have the same ligand structure but whose individual ligands are not polypodally bridged, there is still room for improvement, for example with regard to efficiency, voltage, and lifetime.

[0003] The object of the present invention is therefore to provide improved iridium complexes which are suitable as emitters for use in OLEDs.

[0004] Surprisingly, it has been found that iridium complexes with a hexadentate tripodal ligand having the structure described below solve this problem and are highly suitable for use in an organic electroluminescent device. These iridium complexes and organic electroluminescent devices containing these complexes are therefore the subject of the present invention.

[0005] The invention thus relates to a compound of formula (1), Ir(L) Formula (1) where the ligand L has a structure of the following formula (2): where the ligand L coordinates to the iridium atom via the positions marked with * and where the H atoms not explicitly shown can also be replaced by D and where the following applies to the symbols and indices used: R is the same or different on each occurrence and is H, D, F, a linear alkyl group having 1 to 10 C atoms or a branched or cyclic alkyl group having 3 to 10 C atoms, where the alkyl group may in each case also be deuterated; two adjacent radicals R can form a ring system with one another; R 1< is the same or different on each occurrence and is H, D, a linear alkyl group having 1 to 10 C atoms or a branched or cyclic alkyl group having 3 to 10 C atoms, where the alkyl group may in each case also be deuterated; two adjacent radicals R 1< can form a ring system with one another;R 2< is, identical or different on each occurrence, H, D, a linear alkyl group having 1 to 10 C atoms, a branched or cyclic alkyl group having 3 to 10 C atoms, where the alkyl group may in each case also be deuterated, or a phenyl or biphenyl group, each of which may be substituted by one or more alkyl groups having 1 to 10 C atoms, where the phenyl or biphenyl group or the alkyl groups may in each case also be deuterated; two adjacent radicals R 2< can form a ring system with one another; m is 1, 2 or 3; n is, identical or different on each occurrence, 0, 1, 2 or 3; o is 0 or 1; p is 0, 1 or 2; q is 0, 1 or 2; r is 0, 1 or 2. ;

[0006] The ligand L of formula (2) is thus a hexadentate, tripodal ligand with the three bidentate phenylpyridine subligands. The complex Ir(L) of formula (1) formed with this ligand thus has the following structure: where the symbols and indices have the meanings given above.

[0007] If two R radicals, or two R 1< radicals, or two R 2< radicals form a ring system, this can be monocyclic or polycyclic. The radicals forming a ring system are adjacent, meaning that these radicals bond to carbon atoms that are directly bonded to one another. For the purposes of this description, the phrase "two R radicals can form a ring" is understood to mean, among other things, that the two radicals are linked by a chemical bond with the formal elimination of two hydrogen atoms. This is illustrated by the following scheme:

[0008] A cyclic alkyl group in the sense of this invention is understood to mean a monocyclic, a bicyclic or a polycyclic group.

[0009] In the context of the present invention, a C 1 to C 10 alkyl group includes, for example, the radicals 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, neo-Pentyl, Cyclopentyl, n-Hexyl, s-Hexyl, t-Hexyl, 2-Hexyl, 3-Hexyl, neo-Hexyl, 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, 1,1-Dimethyl-n-hex-1-yl-, 1,1-Dimethyl-n-hept-1-yl-, 1,1-Dimethyl-n-oct-1-yl-, 1,1-diethyl-n-hex-1-yl-, 1-(n-propyl)-cyclohex-1-yl- and 1-(n-butyl)-cyclohex-1-yl- understood.

[0010] If the indices n, p, q or r = 0, a hydrogen or deuterium atom is bonded to the corresponding phenyl or pyridine group instead of the corresponding substituents.

[0011] For m = 1, the ligand L preferably represents a structure of the following formula (3a), for m = 2, the ligand L preferably represents a structure of the following formula (3b) or (3c) and for m = 3, the ligand L preferably represents a structure of the following formula (3d) or (3e), where the symbols and indices have the meanings given above and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0012] The structure of formula (3a) is preferred.

[0013] When o = 1, preferred embodiments are q = 0 and p = 0, 1 or 2 or q = 0, 1 or 2 and p = 0. For o = 1 and p = 1, the ligand preferably has a structure of the following formula (4a), and for o = 1 and p = 2, the ligand preferably has a structure of the following formula (4b), where the symbols and indices have the meanings given above and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0014] In a preferred embodiment of the invention, the indices n on the two phenylpyridine partial ligands that are not substituted with the cyanophenyl or cyanobiphenyl group are 0. In a further preferred embodiment of the invention, these indices n = 1 or 2 and the corresponding radicals R 1< are not H or D. If these indices n = 1, the ligand preferably has a structure of the following formula (5a) or (5b), and if these indices n = 2, the ligand preferably has a structure of the following formula (5c), where the symbols and indices have the meanings given above and R 1< is not H or D and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0015] In a further preferred embodiment of the invention, the index n on the phenylpyridine partial ligands substituted with the cyanophenyl or cyanobiphenyl group is 0. In a further preferred embodiment of the invention, this index n = 1 or 2 and the corresponding radicals R 2< are not H or D. If this index n = 1, the ligand preferably has a structure of the following formula (6a) or (6b), and if this index n = 2, the ligand preferably has a structure of the following formula (6c), where the symbols and indices have the meanings given above and R 2< is not H or D and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0016] Preferably, the ligand L has a structure of the following formula (7), where the symbols and indices have the meanings given above and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0017] In a preferred embodiment of the invention, the substituents R are the same or different on each occurrence and are selected from the group consisting of D, a linear alkyl group having 1 to 6 C atoms, or a branched or cyclic alkyl group having 3 to 6 C atoms, where the alkyl groups may also be deuterated. Particularly preferably, the substituents R are the same or different on each occurrence and are selected from the group consisting of D, a linear alkyl group having 1 to 4 C atoms, or a branched alkyl group having 3 or 4 C atoms, where the alkyl groups may also be deuterated. R is particularly preferably a methyl group or a CD 3 group.

[0018] In a further preferred embodiment of the invention, the substituents R 1< are the same or different on each occurrence and are selected from the group consisting of D, a linear alkyl group having 1 to 6 C atoms or a branched or cyclic alkyl group having 3 to 6 C atoms, where the alkyl groups may each also be deuterated; two adjacent radicals R 1< may each form a ring system with one another. Particularly preferably, the substituents R 1< are the same or different on each occurrence and are selected from the group consisting of D, a linear alkyl group having 1 to 4 C atoms or a branched alkyl group having 3 or 4 C atoms, where the alkyl groups may each also be deuterated; two adjacent radicals R 1< may each form a ring system with one another. R 1< is particularly preferably a methyl group or a CD 3 group.

[0019] In a further preferred embodiment of the invention, the substituents R 2< are identical or different on each occurrence and are selected from the group consisting of D, a linear alkyl group having 1 to 6 C atoms or a branched or cyclic alkyl group having 3 to 6 C atoms, where the alkyl groups may each also be deuterated, or an optionally deuterated phenyl group which may be substituted by one or more optionally deuterated alkyl groups having 1 to 4 C atoms; two adjacent radicals R 2< may form a ring system with one another. Particularly preferably, the substituents R 2< are identical or different on each occurrence and are selected from the group consisting of D, a linear alkyl group having 1 to 4 C atoms or a branched alkyl group having 3 or 4 C atoms, where the alkyl groups may each also be deuterated; Two adjacent radicals R 2< , if they represent alkyl groups, can form a ring system with each other.Particularly preferably, R 2< is a methyl group or a CD 3 group. If R 2< represents an optionally deuterated phenyl group, this is preferably unsubstituted or substituted by one or two optionally deuterated alkyl groups, preferably methyl groups or CD 3 groups, wherein these alkyl groups are then preferably bonded in the ortho position to the linkage of the phenyl group.

[0020] In a further preferred embodiment of the invention, m = 1 or 2, particularly preferably 1.

[0021] In a further preferred embodiment of the invention, n is, identically or differently, 0, 1 or 2 on each occurrence.

[0022] In a further preferred embodiment of the invention, o = 1. If n on the same ligand = 1 and R 2< represents a phenyl group, o = 1 is also preferred.

[0023] In a further preferred embodiment of the invention, p = 0 or 1, particularly preferably = 0.

[0024] In a further preferred embodiment of the invention, q = 0 or 1.

[0025] In a further preferred embodiment of the invention, r = 0 or 1.

[0026] Preferably, several of the above-mentioned preferences occur simultaneously. Therefore, the following applies to the symbols and indices: R is the same or different on each occurrence and is selected from the group consisting of D, a linear alkyl group having 1 to 6 C atoms or a branched or cyclic alkyl group having 3 to 6 C atoms, where the alkyl groups may each also be deuterated; R 1< is the same or different on each occurrence and is selected from the group consisting of D, a linear alkyl group having 1 to 6 C atoms or a branched or cyclic alkyl group having 3 to 6 C atoms, where the alkyl groups may each also be deuterated; two adjacent radicals R 1< can form a ring system with one another;R 2< is, identical or different on each occurrence, selected from the group consisting of D, a linear alkyl group having 1 to 6 C atoms or a branched or cyclic alkyl group having 3 to 6 C atoms, where the alkyl groups may each also be deuterated, or an optionally deuterated phenyl group which may be substituted by one or more optionally deuterated alkyl groups having 1 to 4 C atoms; two adjacent radicals R 2< can form a ring system with one another; m is 1 or 2; n is, identical or different on each occurrence, 0, 1 or 2; o is 1; or o is 0 or 1 if n on the same ligand = 1 and R 2< is a phenyl group; p is 0 or 1; q is 0 or 1; r is 0 or 1. ;

[0027] The following applies particularly to the symbols and indices: R is the same or different on each occurrence and is selected from the group consisting of D, a linear alkyl group having 1 to 4 C atoms or a branched alkyl group having 3 or 4 C atoms, where the alkyl groups may each also be deuterated; R 1< is the same or different on each occurrence and is selected from the group consisting of D, a linear alkyl group having 1 to 4 C atoms or a branched alkyl group having 3 or 4 C atoms, where the alkyl groups may each also be deuterated; two adjacent radicals R 1< can form a ring system with one another;R 2< is, identical or different on each occurrence, selected from the group consisting of D, a linear alkyl group having 1 to 4 C atoms or a branched alkyl group having 3 or 4 C atoms, where the alkyl groups may each also be deuterated, or an optionally deuterated phenyl group which may be substituted by one or more optionally deuterated alkyl groups having 1 to 4 C atoms; two adjacent alkyl groups R 2< can form a ring system with one another; m is 1; n is, identical or different on each occurrence, 0, 1 or 2; o is 1; or o is 0 or 1 if n on the same ligand = 1 and R 2< is a phenyl group; p is 0; q is 0 or 1; r is 0 or 1. ;

[0028] If two radicals R or R 1< or R 2< represent alkyl groups which together form a ring system, this ring system is preferably selected from the structures of the following formulas (Ring-1) to (Ring-7) where the dashed bonds indicate the connection of the two carbon atoms in the ligand and furthermore: R 3< is, identically or differently on each occurrence, H, D or an alkyl group having 1, 2 or 3 C atoms; G is an alkylene group having 1 or 2 C atoms.

[0029] In the structures (ring 1) to (ring 7) depicted above, as well as in the other preferred embodiments of these structures, a double bond is formally depicted between the two carbon atoms. This represents a simplification of the chemical structure, since these two carbon atoms are embedded in an aromatic or heteroaromatic system, and thus the bond between these two carbon atoms formally lies between the degree of a single bond and that of a double bond. The depiction of the formal double bond is therefore not to be interpreted as limiting the structure; rather, it is obvious to the skilled person that this is an aromatic bond.

[0030] If adjacent radicals in the structures according to the invention form an aliphatic ring system, it is preferred if this does not contain any acidic benzylic protons. Benzylic protons are understood to be protons that bond to a carbon atom that is directly bonded to the ligand. This can be achieved by fully substituting the carbon atoms of the aliphatic ring system that bond directly to an aryl or heteroaryl group and not containing any bonded hydrogen atoms. Thus, the absence of acidic benzylic protons in the formulas (Ring-1) to (Ring-3) is achieved by R 3< in the benzylic positions representing an alkyl group. This can also be achieved by having the carbon atoms of the aliphatic ring system that bond directly to a pyridine or phenyl group as the bridgeheads of a bi- or polycyclic structure.Due to the spatial structure of the bi- or polycyclic structure, the protons bound to bridgehead carbon atoms are significantly less acidic than benzylic protons on carbon atoms that are not bound in a bi- or polycyclic structure and are considered non-acidic protons for the purposes of the present invention.

[0031] Examples of suitable groups of the structure (Ring-1) are the structures listed below:

[0032] Examples of suitable groups of the formula (Ring-2) are the structures listed below:

[0033] Examples of suitable groups of the formulas (Ring-3), (Ring-6) and (Ring-7) are the structures listed below:

[0034] Examples of suitable groups of the formula (Ring-4) are the structures listed below:

[0035] Examples of suitable groups of the formula (Ring-5) are the structures listed below:

[0036] In a particularly preferred embodiment of the invention, the ligand L has a structure of the following formula (8), where R, R 1< , R 2< and o have the meanings given above, in particular the preferred meanings given above or the particularly preferred meanings given above, p = 0 or 1, q = 0 or 1 and r = 0 or 1 and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0037] Most preferably, the ligand L has a structure of the following formula (9), where R, R 1< and R 2< have the meanings given above, in particular the preferred meanings given above or the particularly preferred meanings given above, q = 0 or 1 and r = 0 or 1 and the hydrogen atoms not explicitly shown can also be replaced by deuterium.

[0038] The above-mentioned preferred embodiments can be combined with one another in any desired manner. In a particularly preferred embodiment of the invention, the above-mentioned preferred embodiments apply simultaneously.

[0039] Examples of suitable structures according to the invention are the compounds shown below. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 167

[0040] The metal complexes according to the invention are chiral structures. If the ligand L is also chiral, the formation of diastereomers and multiple enantiomer pairs is possible. The complexes according to the invention then include both mixtures of the various diastereomers or the corresponding racemates, as well as the individual isolated diastereomers or enantiomers.

[0041] If ligands with two identical subligands are used in the ortho-metalation, a racemic mixture of the C 1 -symmetric complexes, i.e., the Δ and A enantiomers, is usually obtained. These can be separated using common methods (chromatography on chiral materials / columns or racemate resolution by crystallization), as shown in the following scheme:

[0042] Racemate resolution via fractional crystallization of diastereomeric salt pairs can be performed using conventional methods. This involves oxidizing the neutral Ir(III) complexes (e.g., with peroxides, H 2 O 2 , or electrochemically), treating the resulting cationic Ir(IV) complexes with the salt of an enantiomerically pure, monoanionic base (chiral base), separating the resulting diasteromeric salts by fractional crystallization, and then reducing them to the enantiomerically pure neutral complex using a reducing agent (e.g., zinc, hydrazine hydrate, ascorbic acid, etc.), as schematically shown below:

[0043] In addition, an enantiomerically pure or enantiomerically enriched synthesis is possible by complexation in a chiral medium (e.g. R- or S-1,1-binaphthol).

[0044] If ligands with three different partial ligands are used in the complexation, a diastereomeric mixture of the complexes is usually obtained, which can be separated by common methods (chromatography, crystallization, etc.).

[0045] Enantiomerically pure C 1 -symmetric complexes can also be synthesized specifically, as shown in the following scheme. For this purpose, an enantiomerically pure, C 1 -symmetric ligand is prepared and complexed, the resulting diastereomeric mixture is separated, and the chiral group is subsequently cleaved.

[0046] The compounds of the invention can, in principle, be prepared by various methods. Generally, an iridium salt is reacted with the corresponding free ligand.

[0047] Therefore, a further subject of the present invention is a process for preparing the compounds according to the invention by reacting the corresponding free ligands with iridium alcoholates of the formula (Ir-1), with iridium ketoketonates of the formula (Ir-2), with iridium halides of the formula (Ir-3) or with iridium carboxylates of the formula (Ir-4), Ir(OR) 3 (Ir-1) IrHaI 3 (Ir-3) Ir(OOCR) 3 (Ir-4) where R has the meanings given above, Hal = F, Cl, Br, or I, and the iridium reactants can also be present as the corresponding hydrates. R preferably represents an alkyl group having 1 to 4 carbon atoms.

[0048] Iridium compounds bearing alkoxide and / or halide and / or hydroxyl as well as ketoketonate residues can also be used. These compounds can also be charged. Corresponding iridium compounds that are particularly suitable as starting materials are disclosed in WO 2004 / 085449. Particularly suitable are [IrCl 2 (acac) 2 ] -< , for example Na[IrCl 2 (acac) 2 ], metal complexes with acetylacetonate derivatives as ligand, for example Ir(acac) 3 or tris(2,2,6,6-tetramethylheptane-3,5-dionato)iridium, and IrCl 3 ·xH 2 O, where x is usually a number between 2 and 4.

[0049] The synthesis of the complexes is preferably carried out as described in WO 2002 / 060910 and WO 2004 / 085449. Also particularly suitable is the synthesis in an organic acid or a mixture of an organic acid and an organic solvent, as described in the as yet unpublished application EP19187468.4, with particularly suitable reaction media being, for example, acetic acid or a mixture of salicylic acid and an organic solvent, for example mesitylene. The synthesis can also be activated thermally, photochemically, and / or by microwave radiation. Furthermore, the synthesis can also be carried out in an autoclave at elevated pressure and / or elevated temperature.

[0050] The reactions can be carried out without the addition of solvents or melting aids in a melt of the corresponding ligands to be o-metallated. Solvents or melting aids can also be added if necessary. Suitable solvents are protic or aprotic solvents, such as aliphatic and / or aromatic alcohols (methanol, ethanol, isopropanol, t-butanol, etc.), oligo- and polyalcohols (ethylene glycol, 1,2-propanediol, glycerol, etc.), alcohol ethers (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 (dimethylsulfone, sulfolane, etc.).Suitable melting aids are compounds that are solid at ambient temperature but melt upon heating the reaction mixture, dissolving the reactants to form a homogeneous melt. Particularly suitable are biphenyl, m-terphenyl, triphenylene, R- or S-binaphthol or the corresponding racemate, 1,2-, 1,3-, 1,4-bisphenoxybenzene, triphenylphosphine oxide, 18-crown-6, phenol, 1-naphthol, hydroquinone, etc. The use of hydroquinone is particularly preferred.

[0051] Alternatively, it is also possible to first synthesize the complex which contains a reactive leaving group, for example Cl, Br, I or a boronic acid derivative, instead of the cyanophenyl or cyanobiphenyl group, and in a next step to introduce the cyanophenyl or cyanobiphenyl group by a coupling reaction, for example a Suzuki coupling.

[0052] By these processes, optionally followed by purification, such as recrystallization or sublimation, the compounds according to the invention according to formula (1) can be obtained in high purity, preferably more than 99% (determined by 1< H-NMR and / or HPLC).

[0053] For processing the iridium complexes of the invention from the liquid phase, for example by spin coating or printing processes, formulations of the iridium complexes of the invention are required. These formulations can be, for example, solutions, dispersions, or emulsions. It may be preferred to use mixtures of two or more solvents for this purpose. 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, in particular 3-phenoxytoluene, (-)-fenchone, 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, 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, 3-methylbiphenyl, 1-methylnaphthalene, 1-ethylnaphthalene, ethyl octanoate, diethyl sebacate, octyl octanoate, heptylbenzene, menthyl isovalerate, cyclohexylhexanoate or mixtures of these solvents.

[0054] The present invention therefore further provides a formulation comprising at least one compound according to the invention and at least one further compound. The further compound can be, for example, a solvent, in particular one of the above-mentioned solvents or a mixture of these solvents. However, the further compound can also be another organic or inorganic compound that is also used in the electronic device, for example, a matrix material. This further compound can also be polymeric.

[0055] The compound according to the invention can be used in an electronic device as an active component, preferably as an emitter in the emissive layer of an organic electroluminescent device. The present invention thus further relates to the use of the compounds according to the invention in an electronic device, in particular in an organic electroluminescent device.

[0056] Yet another subject of the present invention is an electronic device comprising at least one compound according to the invention, in particular an organic electroluminescent device.

[0057] An electronic device is understood to be a device that contains an anode, a cathode, and at least one layer, wherein this layer contains at least one organic or organometallic compound. The electronic device according to the invention thus contains an anode, a cathode, and at least one layer containing at least one iridium complex according to the invention.Preferred electronic devices are selected from the group consisting of organic electroluminescent devices (OLEDs, PLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), which include both purely organic solar cells and dye-sensitized solar cells, organic optical detectors, organic photoreceptors, organic field quench devices (O-FQDs), light-emitting electrochemical cells (LECs), oxygen sensors, or organic laser diodes (O-lasers), containing at least one compound according to the invention in at least one layer. Compounds that emit in the infrared are suitable for use in organic infrared electroluminescent devices and infrared sensors.Organic electroluminescent devices are particularly preferred. Active components are generally the organic or inorganic materials introduced between the anode and cathode, for example, charge-injection, charge-transport, or charge-blocking materials, but in particular emission materials and matrix materials. The compounds of the invention exhibit particularly good properties as emission materials in organic electroluminescent devices. A preferred embodiment of the invention is therefore organic electroluminescent devices. Furthermore, the compounds of the invention can be used to generate singlet oxygen or in photocatalysis.

[0058] The organic electroluminescent device contains a cathode, an anode, and at least one emitting layer. In addition to these layers, it may contain further layers, for example, 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. It is possible that one or more hole transport layers are p-doped, for example with metal oxides, such as MoO 3 or WO 3 , or with (per)fluorinated electron-deficient aromatics or with electron-deficient cyano-substituted heteroaromatics (e.g. according to JP 4747558, JP 2006-135145, US 2006 / 0289882, WO 2012 / 095143), or with quinoid systems (e.g. according to EP1336208) or with Lewis acids, or with boranes (e.g.according to US 2003 / 0006411, WO 2002 / 051850, WO 2015 / 049030) or with carboxylates of the elements of the 3rd, 4th or 5th main group (WO 2015 / 018539) and / or that one or more electron transport layers are n-doped.

[0059] Interlayers can also be introduced between two emitting layers, which, for example, have an exciton-blocking function and / or control the charge balance in the electroluminescent device and / or generate charges (charge generation layers, e.g., in layer systems with multiple emitting layers, e.g., in white-emitting OLED components). It should be noted, however, that not every one of these layers necessarily needs to be present.

[0060] The organic electroluminescent device can contain one emitting layer or it can contain multiple emitting layers. If multiple emitting layers are present, these preferably have a total of multiple emission maxima between 380 nm and 750 nm, resulting in overall white emission, i.e. different emitting compounds that can fluoresce or phosphoresce are used in the emitting layers. Particular preference is given to three-layer systems, wherein the three layers exhibit blue, green and orange or red emission (for the basic structure see, for example, WO 2005 / 011013), or systems that have more than three emitting layers. It can also be a hybrid system, wherein one or more layers fluoresce and one or more other layers phosphoresce. A preferred embodiment is tandem OLEDs.White-emitting organic electroluminescent devices can be used for lighting applications or, with a color filter, for full-color displays.

[0061] In a preferred embodiment of the invention, the organic electroluminescent device contains the compound according to the invention as emitting compound in one or more emitting layers.

[0062] When the compound according to the invention is used as an emitting compound in an emitting layer, it is preferably used in combination with one or more matrix materials. The mixture of the compound according to the invention and the matrix material contains between 0.1 and 99 vol. %, preferably between 1 and 90 vol. %, particularly preferably between 3 and 40 vol. %, in particular between 5 and 15 vol. % of the compound according to the invention, based on the total mixture of emitter and matrix material. Accordingly, the mixture contains between 99.9 and 1 vol. %, preferably between 99 and 10 vol. %, particularly preferably between 97 and 60 vol. %, in particular between 95 and 85 vol. % of the matrix material, based on the total mixture of emitter and matrix material.

[0063] In general, any materials known in the art can be used as the matrix material. Preferably, the triplet level of the matrix material is higher than the triplet level of the emitter.

[0064] Suitable matrix materials for the compounds according to the invention are ketones, phosphine oxides, sulfoxides and sulfones, e.g. according to WO 2004 / 013080, WO 2004 / 093207, WO 2006 / 005627 or WO 2010 / 006680, triarylamines, carbazole derivatives, e.g. CBP (N,N-bis-carbazolylbiphenyl), m-CBP or the carbazole derivatives, biscarbazole derivatives, indolocarbazole derivatives disclosed in WO 2005 / 039246, US 2005 / 0069729, JP 2004 / 288381, EP 1205527, WO 2008 / 086851 or US 2009 / 0134784, according to WO 2007 / 063754 or WO 2008 / 056746, indenocarbazole derivatives, e.g. according to WO 2010 / 136109 or WO 2011 / 000455, azacarbazoles, e.g. according to EP 1617710, EP 1617711, EP 1731584, JP 2005 / 347160, bipolar matrix materials, e.g. according to WO 2007 / 137725, silanes, e.g. according to WO 2005 / 111172, azaboroles or boronic esters, e.g. according to WO 2006 / 117052, diazasilole derivatives, e.g. according to WO 2010 / 054729, diazaphosphole derivatives, e.g. B. according to WO 2010 / 054730, triazine derivatives, e.g. according to WO 2010 / 015306, WO 2007 / 063754 or WO 2008 / 056746, zinc complexes, e.g.B. according to EP 652273 or WO 2009 / 062578, dibenzofuran derivatives, e.g. according to WO 2009 / 148015 or WO 2015 / 169412, or bridged carbazole derivatives, e.g. according to US 2009 / 0136779, WO 2010 / 050778, WO 2011 / 042107 or WO 2011 / 088877. For solution-processed OLEDs, polymers, e.g. according to WO 2012 / 008550 or WO 2012 / 048778, oligomers or dendrimers, e.g. according to Journal of Luminescence 183 (2017), 150-158, are also suitable as matrix materials.

[0065] It may also be preferable to use several different matrix materials as a mixture, in particular at least one electron-conducting matrix material and at least one hole-conducting matrix material. A preferred combination is, for example, the use of an aromatic ketone, a triazine derivative, a pyrimidine derivative, a phosphine oxide derivative, or an aromatic lactam with a triarylamine derivative or a carbazole derivative as a mixed matrix for the compound according to the invention. Likewise preferred is the use of a mixture of a charge-transporting matrix material and an electrically inert matrix material (so-called "wide bandgap host"), which is not involved or not significantly involved in charge transport, as described, for example, in WO 2010 / 108579 or WO 2016 / 184540. Likewise preferred is the use of two electron-transporting matrix materials, for example triazine derivatives and lactam derivatives, such as, for example,described in WO 2014 / 094964. Examples of compounds suitable as matrix materials for the compounds of the invention are shown below.

[0066] Preferred biscarbazoles which can be used as matrix materials for the compounds according to the invention are the structures of the following formulas (10) and (11), where the symbols used are: Ar 1< is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, preferably having 6 to 30 aromatic ring atoms, particularly preferably having 6 to 24 aromatic ring atoms, which may each be substituted by one or more radicals R', preferably non-aromatic radicals R'; A 1< is NAr 1< , C(R') 2 , O or S, preferably C(R') 2 ; R' is identical or different on each occurrence and is H, D, F, CN, an alkyl group having 1 to 10 C atoms, preferably having 1 to 4 C atoms, or an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, preferably having 6 to 30 aromatic ring atoms, particularly preferably having 6 to 24 aromatic ring atoms, which may be substituted by one or more substituents selected from the group consisting of D, F, CN or an alkyl group having 1 to 10 C atoms, preferably having 1 to 4 C atoms.

[0067] Preferred embodiments of the compounds of formulas (10) and (11) are the compounds of the following formulas (10a) and (11a), where the symbols used have the meanings given above.

[0068] Preferred dibenzofuran derivatives are the compounds of the following formula (12), where the oxygen can also be replaced by sulfur to form a dibenzothiophene, L 1< represents a single bond or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, preferably having 6 to 24 aromatic ring atoms, which can also be substituted by one or more radicals R', but is preferably unsubstituted, and R' and Ar 1< have the meanings given above. The two groups Ar 1<, which bond to the same nitrogen atom, or a group Ar 1< and a group L, which bond to the same nitrogen atom, can also be linked to one another, for example to form a carbazole.

[0069] Preferred carbazolamines are the structures of the following formulas (13), (14) and (15), where L 1< , R' and Ar 1< have the meanings given above.

[0070] Examples of suitable hole-conducting matrix materials are the compounds shown in the following table. H1 H2 H3 H4 H5 H6 H7 H8 H9 H10 H11 H12 H13 H14 H15 H16 H17 H18 H19 H20 H21 H22 H23 H24 H25 H26 H27 H28 H29 H30 H31 H32 H33 H34 H35 H36 H37 H38 H39 H40 H41 H42 H43 H44 H45 H46 H47 H48 H49 H50 H51 H52 H53 H54 H55 H56 H57

[0071] Preferred triazine or pyrimidine derivatives which can be used as a mixture together with the compounds according to the invention are the compounds of the following formulas (16) and (17), where Ar 1< has the meanings given above.

[0072] Particularly preferred are the triazine derivatives of formula (16).

[0073] In a preferred embodiment of the invention, Ar 1< in formulas (16) and (17) is, on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 6 to 30 aromatic ring atoms, in particular having 6 to 24 aromatic ring atoms, which may be substituted by one or more radicals R'.

[0074] Examples of suitable electron-transporting compounds which can be used as matrix materials together with the compounds according to the invention are the compounds shown in the following table. E1 E2 E3 E4 E5 E6 E7 E8 E9 E10 E11 E12 E13 E14 E15 E16 E17 E18 E19 E20 E21 E22 E23 E24 E25 E26 E27 E28 E29 E30 E31 E32 E33 E34 E35 E36 E37 E38 E39 E40 E41 E42 E43 E44 E45 E46 E47 E48 E49 E50 E51 E52 E53 E54 E55 E56 E57 E58 E59 E60 E61 E62 E63 E64 E65 E66 E67 E68 E69 E70 E71 E72 E73 E74 E75 E76 E77 E78 E79 E80 E81 E81 E82 E83 E84 E85 E86 E87 E88 E89 E90 E91 E92 E93 E94 E95 E96 E97 E98 E99 E100 E101 E102 E103 E104 E105 E106 E107 E108 E109 E110 E111 E112 E113 E114 E115 E116 E117 E118 E119 E120 E121 E122 E123 E124 E125 E126 E127 E128 E129 E130 E131 E132 E133 E134 E135 E136 E137 E138 E139 E140 E141 E142 E143 E144 E145 E146 E147 E148 E149 E150 E151 E152 E153 E154 E155 E156 E157 E158 E159 E160 E161 E162 E163 E164 E165 E166 E167 E168 E169 E170 E171 E172 E173 E174 E175 E176 E177 E178 E179 E180 E181 E182 E183 E184 E185 E186 E187 E188 E189 E190 E191 E192 E193 E194 E195 E196 E197 E198 E199 E200 E201 E202 E203 E204 E205 E206 E207 E208 E209 E210 E211 E212 E213 E214 E215 E216 E217 E218 E219 E220 E221 E222 E223 E224 E225 E226 E227 E228 E229 E230 E231 E232 E233 E234 E235 E236 E237 E238 E239 E240 E241 E242 E243 E244 E245 E246 E247 E248 E249 E250 E251 E252 E253 E254 E255 E256 E257 E258 E259 E260 E261 E262 E263 E264 E265 E266 E267 E268 E269 E270 E271 E272 E273 E274 E275 E276 E277 E278 E279 E280 E281 E282 E283 E284 E285 E286 E287 E288 E289 E300 E301 E302 E303

[0075] Metals with a low work function, metal alloys, or multilayer structures made of different metals are preferred as the cathode, such as alkaline earth metals, alkali metals, main group metals, or lanthanides (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Alloys made of an alkali or alkaline earth metal and silver, for example, an alloy of magnesium and silver, are also suitable. In multilayer structures, other metals with a relatively high work function, such as Ag, can also be used in addition to the metals mentioned, in which case combinations of the metals, such as Mg / Ag, Ca / Ag, or Ba / Ag, are generally used. It may also be preferable to introduce a thin intermediate layer of a material with a high dielectric constant between a metallic cathode and the organic semiconductor.Suitable materials for this purpose include alkali metal or alkaline earth metal fluorides, as well as the corresponding oxides or carbonates (e.g., LiF, Li 2 O, BaF 2 , MgO, NaF, CsF, Cs 2 CO 3 , etc.). Organic alkali metal complexes, such as Liq (lithium quinolinate), are also suitable. The thickness of this layer is preferably between 0.5 and 5 nm.

[0076] Materials with a high work function are preferred as the anode. The anode preferably has a work function greater than 4.5 eV vs. vacuum. Metals with a high redox potential, such as Ag, Pt, or Au, are suitable for this purpose. Metal / metal oxide electrodes (e.g., Al / Ni / NiO x , Al / PtO x ) may also be preferred. For some applications, at least one of the electrodes must be transparent or partially transparent to enable either the irradiation of the organic material (O-SC) or the coupling out of light (OLED / PLED, O-LASER). Preferred anode materials here are conductive mixed metal oxides. Indium tin oxide (ITO) or indium zinc oxide (IZO) are particularly preferred. Also preferred are conductive, doped organic materials, in particular conductive doped polymers, e.g., PEDOT, PANI, or derivatives of these polymers.It is also preferred if a p-doped hole-transport material is applied to the anode as a hole-injection layer. Suitable p-dopants are metal oxides, for example MoO 3 or WO 3 , or (per)fluorinated electron-deficient aromatics. Other suitable p-dopants are HAT-CN (hexacyanohexaazatriphenylene) or the compound NPD9 from Novaled. Such a layer simplifies hole injection into materials with a deep HOMO, i.e., a large HOMO.

[0077] In the further layers, it is generally possible to use all materials as used for the layers according to the prior art, and the person skilled in the art can combine any of these materials with the materials according to the invention in an electronic device without inventive step.

[0078] Suitable charge transport materials which can be used in the hole injection or hole transport layer or electron blocking layer or in the electron transport layer of the organic electroluminescent device according to the invention are, for example, the compounds disclosed in Y. Shirota et al., Chem. Rev. 2007, 107(4), 953-1010 or other materials which are used in these layers according to the prior art. Preferred hole transport materials which can be used in a hole transport, hole injection or electron blocking layer in the electroluminescent device according to the invention are indenofluorenamine derivatives (e.g. according to WO 06 / 122630 or WO 06 / 100896), the amine derivatives disclosed in EP 1661888, hexaazatriphenylene derivatives (e.g. according to WO 01 / 049806), amine derivatives with condensed aromatics (e.g. according to US 5,061,569), the amine derivatives disclosed in WO 95 / 09147, monobenzoindenofluorenamines (e.g.according to WO 08 / 006449), dibenzoindenofluorenamines (e.g. according to WO 07 / 140847), spirobifluorene amines (e.g. according to WO 2012 / 034627, WO2014 / 056565), fluorene amines (e.g. according to EP 2875092, EP 2875699 and EP 2875004), spiro-dibenzopyran amines (e.g. EP 2780325) and dihydroacridine derivatives (e.g. according to WO 2012 / 150001).

[0079] The device is structured accordingly (depending on the application), contacted and finally hermetically sealed, since the lifetime of such devices is drastically reduced in the presence of water and / or air.

[0080] Also preferred is an organic electroluminescent device characterized in that one or more layers are coated using a sublimation process. The materials are vapor-deposited in vacuum sublimation systems at an initial pressure of typically less than 10 -5 mbar, preferably less than 10 -6 mbar. It is also possible for the initial pressure to be even lower or higher, for example, less than 10 -7 mbar.

[0081] Also preferred is an organic electroluminescent device, characterized in that one or more layers are coated using the OVPD (Organic Vapor Phase Deposition) process or by means of carrier gas sublimation. The materials are applied at a pressure between 10 -5 mbar and 1 bar. A special case of this process is the OVJP (Organic Vapor Jet Printing) process, in which the materials are applied directly through a nozzle and thus structured (e.g., BMS Arnold et al., Appl. Phys. Lett. 2008, 92, 053301).

[0082] Also preferred is an organic electroluminescent device, characterized in that one or more layers are produced from solution, such as by spin coating, or by any printing process, such as screen printing, flexographic printing, offset printing, or nozzle printing, but particularly preferably LITI (Light Induced Thermal Imaging, thermal transfer printing) or inkjet printing. Soluble compounds are required for this, which are obtained, for example, by suitable substitution.

[0083] The organic electroluminescent device can also be manufactured as a hybrid system by applying one or more layers from solution and vapor-depositing one or more other layers. For example, it is possible to apply an emitting layer containing a metal complex according to the invention and a matrix material from solution and then vacuum-deposit a hole-blocking layer and / or an electron-transport layer thereon.

[0084] These processes are generally known to the person skilled in the art and can be applied by him without problems to organic electroluminescent devices containing compounds according to formula (1) or the preferred embodiments listed above.

[0085] The electronic devices according to the invention, in particular organic electroluminescent devices, are distinguished from the prior art by their significantly improved lifetime compared to comparable structures that do not have a cyano group on the phenyl or biphenyl substituent. At the same time, a slight improvement in efficiency and voltage is achieved.

[0086] The invention is further illustrated by the following examples, without intending to limit it. Those skilled in the art can use the descriptions to produce further electronic devices according to the invention without inventive step and thus implement the invention within the entire scope of the claims. Examples:

[0087] Unless otherwise stated, the following syntheses are carried out under a protective gas atmosphere in dried solvents. The metal complexes are also handled in the absence of light or under yellow light. The solvents and reagents can be obtained, for example, from Sigma-ALDRICH or ABCR. The respective information in square brackets or the numbers given for individual compounds refer to the CAS numbers of the compounds known from the literature. For compounds that can exhibit multiple tautomeric, isomeric, diastereomeric, and enantiomeric forms, one form is shown as a representative example. A: Synthesis of the ligands L: Example L1:

[0088]

[0089] A mixture of 81.8 g (100 mmol) of 2-(4-{2-[3-(2'-{[Trifluoromethanesulfonyl]-4-yl}-4'-(pyridin-2-yl)-[1,1'-biphenyl]-2-yl)-5-{2-[4-(pyridin-2-yl)-phenyl]ethyl}-phenyl]ethyl}phenyl)pyridine [2375157-32-5], 16.2 g (110 mmol) of 4-cyanophenylboronic acid [126747-14-6], 53.1 g (250 mmol) of tripotassium phosphate, 800 ml of THF and 200 ml of water is treated with vigorous stirring with 1.64 g (4 mmol) of S-Phos and then with 449 mg (2 mmol) of palladium(II) acetate and refluxed for 12 h. heated. After cooling, the aqueous phase is separated, the organic phase is largely concentrated in vacuo, the residue is taken up in 500 ml of ethyl acetate, the organic phase is washed twice with 300 ml of water each time, once with 2% aqueous N-acetylcysteine ​​solution, once with 300 ml of saturated sodium chloride solution and dried over magnesium sulfate.The drying agent is filtered off through a bed of silica gel pre-slurried with ethyl acetate, washed with ethyl acetate, the filtrate is concentrated to dryness, and the residue is recrystallized from approximately 200 ml of acetonitrile at boiling temperature. Yield: 50.2 g (65 mmol), 65%; Purity: approximately 98% according to 1< H NMR.

[0090] The following connections can be represented analogously. e.g. reactants product yield L2 2375157-34-7 70 % 126747-14-6 L3 2375157-36-9 67 % 313546-18-8 L4 2375157-38-1 63 % 856255-58-8 L5 2375157-40-5 69 % 1384855-53-1 L6 2375157-32-5 55 % 1212021-54-9 L7 2375157-36-9 58 % 1212021-54-9 L-Ref3 2375157-36-9 72 % 98-80-6 L100 2375157-32-5 76 % 406482-73-3 L101 2375157-34-7 73 % 406482-73-3 L102 2375157-36-9 75 % 406482-73-3 L103 2375157-40-5 70 % 406482-73-3 L104 2375157-42-7 68 % 406482-73-3 L105 2375157-44-9 63 % 406482-73-3 L106 2375157-34-7 68 % 1800587-08-9 L107 2375157-34-7 65 % 2380354-21-0 L108 2375157-34-7 67 % 1615713-15-9 L109 2375157-42-7 60 % 2291171-92-9 L110 2375157-40-5 1352715-67-3 L111 2375157-36-9 68 % 2242884-56-4 L112 2375157-44-9 61 % 2242884-55-3 C: Representation of the metal complexes Example Ir(L1):

[0091]

[0092] A mixture of 7.71 g (10 mmol) of ligand L1, 4.90 g (10 mmol) of tris-acetylacetonato-iridium(III) [15635-87-7], and 120 g of hydroquinone [123-31-9] is placed in a 1000 mL two-neck round-bottom flask with a glass-jacketed magnetic core. The flask is equipped with a water separator (for media less dense than water) and an air cooler with an argon blanket. The flask is placed in a metal heating dish. The apparatus is purged with argon from above via the argon blanket for 15 min, while the argon is allowed to escape from the side neck of the two-neck flask. A glass-jacketed Pt-100 thermocouple is inserted into the flask via the side neck of the two-neck flask and placed just above the magnetic stirrer bar. The apparatus is then thermally insulated with several loose wraps of household aluminum foil, with the insulation extending to the middle of the riser pipe of the water separator.The apparatus is then rapidly heated to 240–245 °C using a laboratory stirrer, as measured by a Pt-100 thermocouple immersed in the molten, stirred reaction mixture. The reaction mixture is held at 240–245 °C for the next 1 h, during which a small amount of condensate distills off and collects in the water separator. After 1 h, the mixture is allowed to cool to approximately 190 °C, the heating dish is removed, and 100 ml of ethylene glycol is added dropwise. After cooling to 100 °C, 400 ml of methanol is slowly added dropwise. The resulting yellow suspension is filtered through a reverse frit filter, the yellow solid is washed three times with 50 ml of methanol, and then dried under vacuum. The solid thus obtained is dissolved in 200 ml of dichloromethane and filtered through 600 g of silica gel pre-slurried with dichloromethane (column diameter approx. 10 cm) under exclusion of air and light, leaving dark fractions at the start.The core fraction is removed and concentrated in a rotary evaporator, while MeOH is continuously added dropwise until crystallization occurs. After filtration, washing with a small amount of MeOH, and drying in vacuo, the yellow product is further purified by four continuous hot extractions with dichloromethane / i-propanol 1:1 (vv) and then four hot extractions with dichloromethane / acetonitrile (approx. 200 ml each, extraction thimble: standard cellulose Soxhlett thimbles from Whatman) under careful exclusion of air and light. The loss to the mother liquor can be adjusted by adjusting the ratio of dichloromethane (low boilers and good solvent) to i-propanol or acetonitrile (high boilers and poor solvent). Typically, it should be 3–6 wt.% of the initial amount. Other solvents such as toluene, xylene, ethyl acetate, butyl acetate, etc., can also be used for hot extraction.Finally, the product is fractionally sublimed under high vacuum at p ~ 10 -6 < mbar and T ~ 330 - 430 °C. Yield: 4.91 g (5.1 mmol), 51%; Purity: > 99.9% according to HPLC.

[0093] The metal complexes are typically obtained as a 1:1 mixture of the A and Δ isomers / enantiomers. The complex images shown below typically show only one isomer. If ligands with three different partial ligands are used, or if chiral ligands are used as a racemate, the derived metal complexes are obtained as a mixture of diastereomers. These can be separated by fractional crystallization or chromatography, e.g., using an automated column chromatography system (CombiFlash from A. Semrau). If chiral ligands are used in enantiomerically pure form, the derived metal complexes are obtained as a mixture of diastereomers, the separation of which by fractional crystallization or chromatography leads to pure enantiomers. The separated diastereomers or enantiomers can be further purified as described above, e.g., by hot extraction.

[0094] The following connections can be represented analogously: e.g. ligand Product variant / Extractant yield Ir(L2) L2 55 % Ir(L3) L3 53 % Ir(L4) L4 64 % Ir(L5) L5 65 % Ir(L6) L6 57 % Ir(L7) L7 53 % Ir(L-Ref3) L-Ref3 78 % Ir(L100) L100 57 % Ir(L101) L101 53 % Ir(L102) L102 56 % Ir(L103) L103 59 % Ir(L104) L104 61 % Ir(L105) L105 56 % Ir(L106) L106 60 % Ir(L107) L107 64 % Ir(L108) L108 57 % Ir(L109) L109 61 % Ir(L110) L110 60 % Ir(L111) L111 55 % Ir(L112) L112 49 % B: Functionalization of the metal complexes A) Deuteration of the methyl / methylene groups on the pyridine ligands:

[0095] 1 mmol of the clean complex (purity > 99.9%) with x methyl / methylene groups and x = 1 - 6 is dissolved in 50 ml of DMSO-d6 (degree of deuteration > 99.8%) by heating to approximately 180 °C. The solution is stirred for 5 min at 180 °C. The solution is allowed to cool to 80 °C and then rapidly added, with vigorous stirring, to a mixture of 5 ml of methanol-d1 (degree of deuteration > 99.8%) and 10 ml of DMSO-d6 (degree of deuteration > 99.8%), in which 0.3 mmol of sodium hydride has been dissolved. The clear yellow-orange solution is stirred at 80 °C for a further 30 min for complexes with methyl / methylene groups para to the pyridine nitrogen orA further 6 hours for complexes with methyl / methylene groups meta to the pyridine nitrogen is added, then the mixture is cooled using a cold water bath. 20 ml of 1N DCI in D2O is added dropwise at ~60 °C. The mixture is allowed to cool to room temperature, and the mixture is stirred for 5 hours. The solid is filtered off with suction and washed three times with 10 ml of H2O / MeOH (1:1, vv) and then three times with 10 ml of MeOH, and the mixture is dried in vacuo. The solid is dissolved in DCM, the solution is filtered through silica gel, and the filtrate is concentrated in vacuo. MeOH is added dropwise at the same time, thereby causing crystallization. Finally, the mixture is fractionally sublimed as described under "C: Preparation of Metal Complexes, Variant A". Yield typically 80-90%, degree of deuteration > 95%.

[0096] The following deuterated complexes can be prepared analogously: e.g. reactant product yield Ir(L103-D9) Ir(L103) 78 % Ir(L104-D9) Ir(L104) 85 % Example: Production of OLEDs 1) Vacuum-processed devices:

[0097] The production of OLEDs according to the invention and OLEDs according to the prior art is carried out according to a general process according to WO 2004 / 058911, which is adapted to the conditions described here (layer thickness variation, materials used).

[0098] Cleaned glass plates (cleaned in a Miele laboratory dishwasher, using Merck Extran cleaner) coated with 50 nm thick structured ITO (indium tin oxide) are annealed for 15 minutes at 250 °C under nitrogen. The pre-cleaned ITO substrates are subjected to a two-gas plasma process (oxygen followed by argon) for final cleaning of the ITO surface and adjustment of the ITO work function. These coated glass plates form the substrates onto which the OLEDs are applied. All materials are applied by thermal vacuum deposition. The emission layer always consists of at least one matrix material (host material) and an emitting dopant (emitter), which is added to the matrix material(s) in a specific volume fraction by co-evaporation. A specification such as M1:M2:Ir-Emitter (29.5%:58.5:12%) means that the material M1 has a volume fraction of 29.5%, M2 in a volume fraction of 58.5%, and the IR emitter in a volume fraction of 12% of the layer. Similarly, the electron transport layer also consists of a mixture of two materials.

[0099] The OLEDs essentially have the following layer structure: ITO substrate / Hole injection layer 1 (HIL1) consisting of HTM1 doped with 5% NDP-9 (commercially available from Novaled), 20 nm / Hole transport layer 1 (HTL1) consisting of HTM1, 40 nm / Hole transport layer 2 (HTL2), 20 nm / Emission layer (EML), see Table 1 / Hole blocking layer (HBL), see Table 1 / Electron transport layer (ETL), see Table 1 / Electron injection layer (EIL), see Table 1 / 100 nm thick aluminum layer as cathode. The materials used to manufacture the OLEDs are shown in Table 3.

[0100] The OLEDs are characterized as standard. For this purpose, the electroluminescence spectra, current efficiency (measured in cd / A), power efficiency (measured in lm / W), and external quantum efficiency (EQE, measured in percent) are determined as a function of luminance, calculated from current-voltage-luminance characteristics (IUL characteristics) assuming a Lambertian radiation pattern, as well as the lifetime. The electroluminescence spectra are determined at a luminance of 1000 cd / m², and the CIE 1931 x and y color coordinates are calculated from them. The lifetime LD90 is defined as the time after which the luminance has dropped to 90% of the starting luminance when operated at an initial brightness of 10000 cd / m². The OLEDs can also be operated initially at other starting luminances. The values ​​for the lifetime can then be converted to a value for other starting luminances using conversion formulas known to the expert. Use of compounds according to the invention as emitter materials in phosphorescent OLEDs

[0101] The compounds of the invention can be used, among other things, as phosphorescent emitter materials in the emission layer of OLEDs. The iridium compounds shown in Table 3 were used as a comparison according to the state of the art. The OLED results are summarized in Table 2.

[0102] As can be seen from the results, the compounds according to the invention, when used as emitters in an OLED, lead to a slight improvement in efficiency and voltage with a simultaneous significant improvement in lifetime, for example a 60% improvement in lifetime in the case of the complex Ir(L100) according to the invention compared to the complex Ir-Ref.1 according to the prior art, which has the same structure as Ir(L100) but does not contain a cyano group on the biphenyl substituent. Table 1: Structure of the OLEDs e.g. EML thickness HBL thickness ETL thickness URGENT Ref.D1 M1:M2:Ir-Ref.1 (29.5%:58.5%:12%) 40 nm HBL1 5nm ETM1:ETM2 (50%:50%) 30 nm ETM2 1 nm Ref.D2 M1:M2:Ir-Ref.2 (29.5%:58.5%:12%) 40 nm HBL1 5nm ETM1:ETM2 (50%:50%) 30 nm ETM2 1 nm Ref.D3 <h2 style=";text-align:left;direction:ltr">M1:M2:Ir(L-Ref3) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D1 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L1) (29.5%:58.5%:12%) <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm <h2 style=";text-align:left;direction:ltr"> 40 nm <h2 style=";text-align:left;direction:ltr"> 30 nm D2 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L2) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D3 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L3) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D4 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L4) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D5 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L5) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D6 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L6) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D7 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L7) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D100 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L100) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D101 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L101) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D102 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L102) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D103 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L103) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm <h2 style=";text-align:left;direction:ltr"> D103-D <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L103-D) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr">ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D104 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L104) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm <h2 style=";text-align:left;direction:ltr"> D104-D <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L104-D) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D105 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L105) (46.0%:46%:8%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D106 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L106) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D107 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L107) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D108 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L108) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D109 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L109) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm D110 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L110) <h2 style=";text-align:left;direction:ltr"> HBL1 <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 <h2 style=";text-align:left;direction:ltr"> ETM2 <h2 style=";text-align:left;direction:ltr"> (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> 5nm <h2 style=";text-align:left;direction:ltr"> (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> 1 nm D110 <h2 style=";text-align:left;direction:ltr"> M1:M2:Ir(L111) (29.5%:58.5%:12%) 40 nm <h2 style=";text-align:left;direction:ltr"> HBL1 5nm <h2 style=";text-align:left;direction:ltr"> ETM1:ETM2 (50%:50%) 30 nm <h2 style=";text-align:left;direction:ltr"> ETM2 1 nm <h2 style=";text-align:left;direction:ltr"> Tabelle 2: Ergebnisse der Vakuum-prozessierten OLEDs <h2 style=";text-align:left;direction:ltr"> (Eff., EQE, Spannung, CIE bei 1000 cd / m2< ; Lebensdauer LD90 bei 10000 cd / m2< ) <h2 style=";text-align:left;direction:ltr"> Bsp. <h2 style=";text-align:left;direction:ltr"> Eff. [cd / A] <h2 style=";text-align:left;direction:ltr"> Eff. [lm / W] <h2 style=";text-align:left;direction:ltr"> EQE [%] <h2 style=";text-align:left;direction:ltr"> Spannung [V] <h2 style=";text-align:left;direction:ltr"> CIE [x / y] <h2 style=";text-align:left;direction:ltr"> LD90 [h] <h2 style=";text-align:left;direction:ltr"> Ref.D1 93.2 88.8 24.8 3.30 0.363 / 0.614 1040 <h2 style=";text-align:left;direction:ltr"> Ref.D2 89.6 94.7 24.1 3.18 0.301 / 0.650 790 <h2 style=";text-align:left;direction:ltr"> Ref.D3 82.9 86.4 21.6 3.02 0.347 / 0.626 650 D1 87.1 97.9 23.6 2.80 0.350 / 0.617 730 D2 90.2 103.2 23.4 2.75 0.346 / 0.623 840 D3 89.2 96.8 23.3 2.90 0.320 / 0.664 710 D4 91.2 104.4 23.5 2.74 0.348 / 0.621 860 D5 90.0 101.8 23.4 2.73 0.350 / 0.620 700 D6 84.9 100.7 22.8 2.64 0.327 / 0.637 630 D7 84.4 99.7 22.7 2.66 0.324 / 0.642 630 D100 95.2 91.8 25.2 3.26 0.363 / 0.614 1660 D101 96.6 96.3 25.8 3.15 0.340 / 0.627 1700 D102 96.0 96.1 25.8 3.17 0.341 / 0.624 2000 D103 90.9 101.3 24.5 2.82 0.348 / 0.621 1370 <h2 style=";text-align:left;direction:ltr"> D103-D 89.4 99.8 24.5 2.85 0.346 / 0.619 1580 D104 85.5 90.6 22.8 2.96 0.339 / 0.628 1230 <h2 style=";text-align:left;direction:ltr"> D104-D 84.7 89.8 22.7 2.95 0.338 / 0.626 1460 D105 93.2 97.1 24.8 3.02 0.333 / 0.634 1280 D106 92.4 92.3 24.4 3.11 0.334 / 0.635 1130 D107 93.1 93.5 24.5 3.09 0.336 / 0.632 1100 D108 93.2 94.0 24.5 3.18 0.332 / 0.633 1060 D109 90.1 94.0 23.0 3.10 0.332 / 0.633 1130 D110 90.7 100.7 24.4 2.80 0.346 / 0.624 1220 D111 97.5 99.2 25.9 3.01 0.331 / 0.636 2000 Table 3: Structural formulas of the materials used HTM1 [1365840-52-3] HTM2 [1450933-44-4] M1 M2 [1643479-47-3] [1822310-86-0] HBL1 [1955543-57-3] ETM1 [1819335-36-8] ETM2[25387-93-3] Ir-Ref.1 [2375153-43-6] Ir-Ref.2 WO2019 / 158453

Claims

1. A compound of the formula (1)         Ir(L)     Formula (1) wherein the ligand L has a structure of the following formula (2): wherein the ligand L coordinates to the iridium atom via the positions identified by * and wherein the hydrogen atoms not explicitly shown may optionally be replaced by D, and wherein the symbols and indices used are as follows: R is the same or different at each occurrence, and is H, D, F, a linear alkyl group having 1 to 10 carbon atoms or a branched or cyclic alkyl group having 3 to 10 carbon atoms, wherein the alkyl group in each case may optionally be deuterated; and wherein, optionally, two adjacent R radicals together can form a ring system; R1 is the same or different at each occurrence, and is H, D, a linear alkyl group having 1 to 10 carbon atoms or a branched or cyclic alkyl group having 3 to 10 carbon atoms, wherein the alkyl group R2 in each case may optionally be deuterated; and wherein, optionally, two adjacent R1 radicals together can form a ring system; is the same or different at each occurrence, and is H, D, a linear alkyl group having 1 to 10 carbon atoms, a branched or cyclic alkyl group having 3 to 10 carbon atoms, wherein the alkyl group in each case may optionally be deuterated; or a phenyl or biphenyl group, each of which may be substituted by one or more alkyl groups having 1 to 10 carbon atoms, wherein the phenyl or biphenyl group, or the alkyl groups, may each optionally be deuterated; and wherein, optionally, two adjacent R2 radicals together can form a ring system; m is 1, 2 or 3; n is the same or different at each occurrence, and is 0, 1, 2 or 3; o is 0 or 1 ; p is 0, 1 or 2; q is 0, 1 or 2; and r is 0, 1 or 2.

2. The compound of claim 1, characterized in that when m = 1, the ligand L is a structure of the formula (3a), when m = 2 the ligand L is a structure of the formula (3b) or (3c), and when m = 3 the ligand L is a structure of the formula (3d) or (3e): wherein the hydrogen atoms not explicitly shown may optionally be replaced by D, and the symbols and indices have the definitions given in claim 1.

3. The compound of claim 1 or 2, characterized in that when o = 1 and p = 1, the ligand L has a structure of the formula (4a); and in that when o = 1 and p = 1, the ligand L has a structure of the formula (4b): wherein the hydrogen atoms not explicitly shown may optionally be replaced by D, and the symbols and indices have the definitions given in claim 1.

4. The compound of any one or more of claims 1 to 3, characterized in that the ligand L has a structure of the formula (7): wherein the hydrogen atoms not explicitly shown may optionally be replaced by D, and the symbols and indices have the definitions given in claim 1.

5. The compound of any one or more of claims 1 to 4, characterized in that the substituents are as follows: R is the same or different at each occurrence, and is selected from the group consisting of D, a linear alkyl group having 1 to 6 carbon atoms or a branched or cyclic alkyl group having 3 to 6 carbon atoms, wherein the alkyl groups may each optionally be deuterated; R1 is the same or different at each occurrence, and is selected from the group consisting of D, a linear alkyl group having 1 to 6 carbon atoms or a branched or cyclic alkyl group having 3 to 6 carbon atoms, wherein the alkyl groups may each optionally be deuterated; and wherein, optionally, two adjacent R1 radicals together can form a ring system; R2 is the same or different at each occurrence, and is selected from the group consisting of D, a linear alkyl group having 1 to 6 carbon atoms or a branched or cyclic alkyl group having 3 to 6 carbon atoms, wherein the alkyl groups may each optionally be deuterated; or an optionally deuterated phenyl group which may be substituted by one or more optionally deuterated alkyl groups having 1 to 4 carbon atoms; and wherein, optionally, two adjacent R2 radicals together can form a ring system.

6. The compound of any one or more of claims 1 to 5, characterized in that the symbols and indices are as follows: R is the same or different at each occurrence, and is selected from the group consisting of D, a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 or 4 carbon atoms, wherein the alkyl groups may each optionally be deuterated; R1 is the same or different at each occurrence, and is selected from the group consisting of D, a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 or 4 carbon atoms, wherein the alkyl groups may each optionally be deuterated; and wherein, optionally, two adjacent R1 radicals together can form a ring system; R2 is the same or different at each occurrence, and is selected from the group consisting of D, a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 or 4 carbon atoms, wherein the alkyl groups may each optionally be deuterated; or an optionally deuterated phenyl group which may be substituted by one or more optionally deuterated alkyl groups having 1 to 4 carbon atoms; and wherein, optionally, two adjacent R2 radicals together can form a ring system; m is 1 or 2; n is the same or different at each occurrence, and is 0, 1 or 2; o is 1; or o is 0 or 1 when n = 1 on the same ligand and R2 is a phenyl group; p is 0 or 1 ; q is 0 or 1 ; r is 0 or 1 .

7. The compound of any one or more of claims 1 to 6, characterized in that the ligand L has a structure of the formula (8): wherein the hydrogen atoms not explicitly shown may optionally be replaced by D, R, R1, R2 and o have the definitions given in claim 1, p = 0 or 1, q = 0 or 1 and r = 0 or 1.

8. The compound of any one or more of claims 1 to 7, characterized in that the ligand L has a structure of the formula (9): wherein the hydrogen atoms not explicitly shown may optionally be replaced by D, R, R1 and R2 have the definitions given in claim 1, q = 0 or 1 and r = 0 or 1.

9. A process for preparing a compound as claimed in any one or more of claims 1 to 8 by reaction of the free ligand L with iridium alkoxides of the formula (Ir-1), with iridium ketoketonates of the formula (Ir-2), with iridium halides of the formula (Ir-3), or with iridium carboxylates of the formula (Ir-4), or with iridium compounds that bear both alkoxide and / or halide and / or hydroxy and / or ketoketonate radicals,         Ir(OR)3     (Ir-1)         IrHaI3     (Ir-3)         Ir(OOCR)3     (Ir-4) wherein R has the definitions given in claim 1, Hal = F, Cl, Br or I, and the iridium reactants may optionally take the form of the corresponding hydrates.

10. A formulation comprising at least one compound of any one or more of claims 1 to 8 and at least one solvent.

11. A use of a compound of any one or more of claims 1 to 8 in an electronic device.

12. An electronic device comprising at least one compound of any one or more of claims 1 to 8.

13. The electronic device of claim 12 which is an organic electroluminescent device, characterized in that the compound of any one or more of claims 1 to 8 is used as an emitting compound in one or more emitting layers.