Mononuclear tripodal hexadentate iridium complex for use in OLEDs

Abstract

The present invention relates particularly to an iridium complex suitable for use as an emitter in organic electroluminescent devices.

Description

Technology Field

[0001] The present invention relates to an iridium complex suitable for use as an emitter in organic electroluminescent devices, particularly. Background Technology

[0002] According to the prior art, triplet emitters used in phosphorescent organic electroluminescent devices (OLEDs) are, in particular, bis- and tris-ortho-metallated iridium complexes having aromatic ligands, wherein the ligands pass through a negatively charged carbon atom and an uncharged nitrogen atom. Examples of such complexes are tris(phenylpyridyl)iridium(III) and derivatives thereof. Complexes of this type are also known to have polypodal ligands, as described, for example, in US 7,332,232, WO 2016 / 124304, and WO 2019 / 158453. Although these complexes having polypodal ligands exhibit advantages over complexes having the same ligand structure without polypodal bridging of individual ligands within them, there is still a need for improvement, for example, with respect to efficiency, voltage, and lifetime. The problem to be solved

[0003] Accordingly, the problem addressed by the present invention is to provide an improved iridium complex suitable as an emitter for use in OLEDs. means of solving the problem

[0004] Surprisingly, this problem is solved by an iridium complex having a hexadentate tripodal ligand having the following structure, which is found to be very well suitable for use in organic electroluminescent devices. Accordingly, the present invention provides these iridium complexes and an organic electroluminescent device comprising these complexes.

[0005] Accordingly, the present invention provides a compound of formula (1):

[0006] Ir(L) Equation (1)

[0007] The ligand L in the formula has the structure of the following formula (2):

[0008]

[0009] In the formula, ligand L coordinates to the iridium atom through the position identified by *, and hydrogen atoms not explicitly indicated may also be replaced by D, and the symbols and indices used are as follows:

[0010] R is the same or different in each case 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 in each case the alkyl group may also be deuterated; wherein two adjacent R radicals can form a ring system together;

[0011] R 1 is the same or different in each case 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 in each case the alkyl group may also be deuterated; and wherein two adjacent R 1 Radicals can form a ring system together;

[0012] R 2 Each of the following is the same or different in each case 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 each case the alkyl group may also be deuterated), or a phenyl or biphenyl group (each of which may be substituted with one or more alkyl groups having 1 to 10 carbon atoms), wherein the phenyl or biphenyl group, or the alkyl group, may each also be deuterated; where two adjacent R2 radicals may together form a ring system.

[0013] m is 1, 2, or 3;

[0014] n is the same or different in each case, and is 0, 1, 2, or 3;

[0015] o is 0 or 1;

[0016] p is 0, 1, or 2;

[0017] q is 0, 1, or 2;

[0018] r is 0, 1, or 2.

[0019] Therefore, the ligand L of Equation (2) is a hexadentate tripodal ligand having three bidentate phenylpyridine subligands. Thus, the complex Ir(L) of Equation (1) formed by that ligand has the following structure:

[0020]

[0021] In the expression, the symbols and indices have the definitions given above.

[0022] 2 R radicals or 2 R 1 Radical or 2 R 2 When radicals form a ring system together, it may be monocyclic or polycyclic. In this case, the radicals forming the ring system together are adjacent, meaning that these radicals are bonded to carbon atoms directly connected to each other. The phrase that two R radicals may form a ring together should be understood, in the context of this detailed description specifically, to mean that two radicals are connected to each other by chemical bonds with the formal removal of two hydrogen atoms. This is illustrated by the following diagram:

[0023]

[0024] In the context of the present invention, a cyclic alkyl group is understood to mean a monocyclic, bicyclic, or polycyclic group.

[0025] In the context of the present invention, C1- to C 10- The alkyl group is, 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, It is understood to mean 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 radicals.

[0026] When indices n, p, q and r are 0, instead of the corresponding substituent, a hydrogen or deuterium atom is bonded to the phenyl or pyridine group corresponding in each case.

[0027] When m=1, it is preferable that the ligand L has the structure of formula (3a) below, when m=2, it is preferable that the ligand L has the structure of formula (3b) or (3c) below, and when m=3, it is preferable that the ligand L has the structure of formula (3d) or (3e) below:

[0028]

[0029]

[0030] The symbols and indices in the formula have the definitions given above, and hydrogen atoms not explicitly indicated may also be replaced with deuterium.

[0031] The structure of formula (3a) is desirable:

[0032] When o = 1, a preferred embodiment is q = 0 and p = 0, 1 or 2, or q = 0, 1 or 2 and p = 0. When o = 1 and p = 1, the ligand preferably has the structure of the following formula (4a), and when o = 1 and p = 2, the ligand preferably has the structure of the following formula (4b):

[0033]

[0034]

[0035] The symbols and indices in the formula have the definitions given above, and hydrogen atoms not explicitly indicated may also be replaced with deuterium.

[0036] In a preferred embodiment of the present invention, the index n on two phenylpyridine subligands not substituted by cyanophenyl or cyanobiphenyl groups is 0. In a further preferred embodiment of the present invention, these indices n are 1 or 2, and the corresponding R 1 The radical is not H or D. When these indices n is 1, the ligand preferably has the structure of formula (5a) or (5b) below, and when these indices n is 2, the ligand preferably has the structure of formula (5c) below:

[0037]

[0038]

[0039] The symbols and indices in the expression have the definitions given above, and R 1 Hydrogen atoms that are not H or D and are not explicitly indicated may also be replaced with deuterium.

[0040] In a further preferred embodiment of the present invention, the index n on the phenylpyridine subligand substituted by a cyanophenyl or cyanobiphenyl group is 0. In a further preferred embodiment of the present invention, this index n is 1 or 2, and the corresponding R2 The radical is not H or D. When this index n is 1, the ligand preferably has the structure of formula (6a) or (6b) below, and when this index n is 2, the ligand preferably has the structure of formula (6c) below:

[0041]

[0042]

[0043] The symbols and indices in the expression have the definitions given above, and R 2 Hydrogen atoms that are not H or D and are not explicitly indicated may also be replaced with deuterium.

[0044] Ligand L preferably has the structure of formula (7):

[0045]

[0046] The symbols and indices in the formula have the definitions given above, and hydrogen atoms not explicitly indicated may also be replaced with deuterium.

[0047] In a preferred embodiment of the present invention, the substituent R 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, each of which may also be deuterated. More preferably, the substituent R 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, each of which may also be deuterated. Particularly preferably, R is a methyl group or a CD3 group.

[0048] In a further preferred embodiment of the present invention, substituent R 1is the same or different in each case 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 each alkyl group may also be deuterated; and wherein two adjacent R 1 Radicals can form a ring system together. More preferably, substituent R 1 is the same or different in each case 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 each alkyl group may also be deuteriden; and wherein two adjacent R 1 Radicals can form a ring system together. Particularly preferably, R 1 It is a methyl group or a CD3 group.

[0049] In a further preferred embodiment of the present invention, substituent R 2 is selected from the group consisting of D, which is the same or different in each case and may be substituted by 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 group may each also be deuterinated), or an optionally deuterinated phenyl group having 1 to 4 carbon atoms, which may be substituted by one or more optionally deuterinated alkyl groups; wherein 2 adjacent R 2 Radicals can form a ring system together. More preferably, substituent R 2 is the same or different in each case 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 each alkyl group may also be deuteriden; and wherein two adjacent R 2Radicals can form a ring system together if they are alkyl groups. Particularly preferably, R 2 is a methyl group or a CD3 group. R 2 When is an optionally deuterated phenyl group, it is preferably unsubstituted or substituted with one or two optionally deuterated alkyl groups, preferably a methyl group or a CD3 group, and these alkyl groups are then preferably bonded at an ortho position to the linkage to the phenyl group.

[0050] In a further preferred embodiment of the present invention, m = 1 or 2, more preferably 1.

[0051] In a further preferred embodiment of the present invention, n is the same or different in each case and is 0, 1, or 2.

[0052] In a further preferred embodiment of the present invention, o = 1. n on the same ligand is 1 and R 2 When α is a phenyl group, it is also desirable for 0=1.

[0053] In a further preferred embodiment of the present invention, p = 0 or 1, more preferably 0.

[0054] In a further preferred embodiment of the present invention, q = 0 or 1.

[0055] In a further preferred embodiment of the present invention, r = 0 or 1.

[0056] Preferably, two or more of the above-mentioned desirables occur simultaneously. Accordingly, preferably, the symbols and indices are as follows:

[0057] R is the same or different in each case 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 each alkyl group may also be deuterated;

[0058] R 1 is the same or different in each case 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 each alkyl group may also be deuterated; and wherein two adjacent R 1 Radicals can form a ring system together;

[0059] R 2 is selected from the group consisting of D, which is the same or different in each case and may be substituted by 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 group may each also be deuterinated), or an optionally deuterinated phenyl group having 1 to 4 carbon atoms, which may be substituted by one or more optionally deuterinated alkyl groups; wherein two adjacent R 2 Radicals can form a ring system together;

[0060] m is 1 or 2;

[0061] n is the same or different in each case, and is 0, 1, or 2;

[0062] o is 1 or; or n on the same ligand is 1 and R 2 When ga is a phenyl group, o is 0 or 1;

[0063] p is 0 or 1;

[0064] q is 0 or 1;

[0065] r is 0 or 1.

[0066] More preferably, the symbols and indices are as follows:

[0067] R is the same or different in each case 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 each alkyl group may also be deuterated;

[0068] R 1 is the same or different in each case 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 each alkyl group may also be deuteriden; and wherein two adjacent R 1 Radicals can form a ring system together;

[0069] R 2 is selected from the group consisting of D, which is the same or different in each case and may be substituted by a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 or 4 carbon atoms (wherein the alkyl group may each also be deuterinated), or an optionally deuterinated phenyl group having 1 to 4 carbon atoms; wherein two adjacent alkyl groups R 2 It is possible to form a ring system together;

[0070] m is 1;

[0071] n is the same or different in each case, and is 0, 1, or 2;

[0072] o is 1 or; or n on the same ligand is 1 and R 2 When ga is a phenyl group, o is 0 or 1;

[0073] p is 0;

[0074] q is 0 or 1;

[0075] r is 0 or 1.

[0076] 2 Rs or Rs1 or R 2 The radicals are alkyl groups that form a ring system with each other, and this ring system is preferably selected from the structures of the following formulas (ring-1) to (ring-7):

[0077]

[0078] In the formula, the dotted bonds represent the connection of two carbon atoms within the ligand, and also:

[0079] R 3 is the same or different in each case, and is an H, D, or an alkyl group having 1, 2, or 3 carbon atoms;

[0080] G is an alkylene group having one or two carbon atoms.

[0081] In the structures (ring-1) through (ring-7) described above and additional embodiments of these structures specified as preferred, a double bond is formed between two carbon atoms in a formal sense. This simplifies the chemical structure because these two carbon atoms are included in an aromatic or heteroaromatic system, and the bond between these two carbon atoms is formally between the bond level of a single bond and the bond level of a double bond. Therefore, the description of the formal double bond should not be interpreted to limit the structure; instead, it will be obvious to those skilled in the art that it is an aromatic bond.

[0082] In the structure of the present invention, when adjacent radicals form an aliphatic ring system, it is preferable that the latter does not have any acidic benzyl protons. A benzyl proton is understood to mean a proton that binds to a carbon atom directly bonded to a ligand. This can be achieved thanks to a carbon atom in an aliphatic ring system that directly binds to an aryl or heteroaryl group that is completely substituted and does not contain any bonded hydrogen atoms. For example, in formulas (ring-1) to (ring-3), the absence of acidic benzyl protons is due to R at the benzyl position. 3 This is achieved in that it is an alkyl group. Additionally, this can also be achieved thanks to a carbon atom in an aliphatic ring system that is directly bonded to a pyridine or phenyl group, which is a bridgehead of a dicyclic or polycyclic structure. The proton bonded to the bridgehead carbon atom is significantly less acidic than the benzyl proton on the unbonded carbon atom within the dicyclic or polycyclic structure due to the spatial structure of the dicyclic or polycyclic structure, and is considered a non-acidic proton in the context of the present invention.

[0083] Examples of suitable forms for structure (Ring-1) are the structures listed below:

[0084]

[0085] Examples of suitable forms for formula (Ring-2) are the structures listed below:

[0086]

[0087] Examples of suitable forms for formulas (Ring-3), (Ring-6), and (Ring-7) are the structures listed below:

[0088]

[0089] Examples of suitable forms for formula (Ring-4) are the structures listed below:

[0090]

[0091] Examples of suitable forms for formula (Ring-5) are the structures listed below:

[0092]

[0093] In a particularly preferred embodiment of the present invention, the ligand L has the structure of the following formula (8):

[0094]

[0095] Among the foods R, R 1 , R 2 and o have the definitions given above, particularly the preferred definition mentioned above or the particularly preferred definition mentioned above, where p = 0 or 1, q = 0 or 1 and r = 0 or 1, and any hydrogen atoms not explicitly indicated may also be replaced with deuterium.

[0096] Most preferably, the ligand L has the structure of the following formula (9):

[0097]

[0098] Among the foods R, R 1 and R 2 has the definition given above, in particular the preferred definition mentioned above or the particularly preferred definition mentioned above, where q = 0 or 1 and r = 0 or 1, and any hydrogen atom not explicitly indicated may also be replaced with deuterium.

[0099] The preferred embodiments mentioned above may be combined with one another if desired. In a particularly preferred embodiment of the present invention, the preferred embodiments mentioned above are applied simultaneously.

[0100] An example of a suitable structure of the present invention is a compound shown below.

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126] The metal complex of the present invention has a chiral structure. Additionally, if the ligand L is also chiral, the formation of diastereomers and multiple enantiomer pairs is possible. In that case, the complex of the present invention comprises a mixture of different diastereomers or corresponding racemic mixtures and both individual isolated diastereomers or enantiomers.

[0127] When a ligand having two identical subligands is used in ortho-metallation, the result is typically a C1-symmetric complex, namely a racemic mixture of Δ and Λ enantiomers. These can also be separated by standard methods (chromatography on a chiral material / column or optical resolution by crystallization), as shown in the following diagram:

[0128]

[0129] Optical resolution of diastereomeric salt pairs through fractional crystallization can be carried out by conventional methods. One option for this purpose is to oxidize an uncharged Ir(III) complex (e.g., using peroxide or H2O2, or by electrochemical means), as schematically illustrated below, add a salt of a monoanionic base (chiral base) that is enantiomerically pure to the cationic Ir(IV) complex thus produced, separate the resulting diastereomeric salt by fractional crystallization, and then reduce it with a reducing agent (e.g., zinc, hydrazine hydrate, ascorbic acid, etc.) to produce an enantiomerically pure uncharged complex:

[0130]

[0131] In addition, enantiomerically pure or enantiomerically rich synthesis is possible by complexation in a chiral medium (e.g., R- or S-1,1-binaphthol).

[0132] When a ligand having three different sub-ligands is used in complexation, what is typically obtained is a mixture of diastereomers of the complex that can be separated by standard methods (chromatography, crystallization, etc.).

[0133] Enantiomerically pure C1-symmetric complexes can also be selectively synthesized as shown in the following scheme. For this purpose, enantiomerically pure C1-symmetric ligands are prepared and complexed, the obtained diastereomer mixture is separated, and then the chiral groups are desorbed.

[0134]

[0135] The compounds of the present invention can, in principle, be prepared by various methods. Generally, for this purpose, an iridium salt is reacted with a corresponding free ligand.

[0136] Accordingly, the present invention further provides a method for preparing a compound of the present invention by reacting a suitable free ligand with an iridium alkoxide of formula (Ir-1), an iridium ketoketonate of formula (Ir-2), an iridium halide of formula (Ir-3), or an iridium carboxylate of formula (Ir-4).

[0137]

[0138] In the formula, R has the definition given above, Hal = F, Cl, Br, or I, and the iridium reactant may also be in the form of a corresponding hydrate. Here, R is preferably an alkyl group having 1 to 4 carbon atoms.

[0139] Likewise, iridium compounds having alkoxide and / or halide and / or hydroxyl and ketoketonate radicals of both can be used. These compounds may also be charged. Corresponding iridium compounds particularly suitable as reactants are disclosed in WO 2004 / 085449. [IrCl2(acac)2] - , for example, Na[IrCl2(acac)2], metal complexes having an acetylacetonate derivative as a ligand, for example, Ir(acac)3 or tris(2,2,6,6-tetramethylheptane-3,5-dionato)iridium, and IrCl3·xH2O (where x is typically a number from 2 to 4) are particularly suitable.

[0140] The synthesis of the complex is preferably carried out as described in WO 2002 / 060910 and WO 2004 / 085449. The synthesis is also particularly suitable in organic acids or in a mixture of organic acids and organic solvents, as described in the application EP19187468.4, which has not yet been disclosed, and particularly suitable reaction media are, for example, acetic acid or a mixture of salicylic acid and an organic solvent, for example, mesitylene. In this case, the synthesis may also be activated by thermal or photochemical means and / or microwave radiation. Additionally, the synthesis may also be carried out in an autoclave at high pressure and / or high temperature.

[0141] The reaction can be carried out in the melt of the corresponding ligand to be o-metallated without adding a solvent or melting aid. Optionally, it is also possible to add a solvent or melting aid. 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, propane-1,2-diol, 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, rutidine, 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 in solid form at room temperature but melt when the reaction mixture is heated, dissolving the reactants to form a homogeneous melt. Particularly suitable are biphenyl, m-terphenyl, triphenyl, R- or S-binaphthol or otherwise corresponding racemic mixtures, 1,2-, 1,3- or 1,4-bisphenoxybenzene, triphenylphosphine oxide, 18-crown-6, phenol, 1-naphthol, hydroquinone, etc. Here, the use of hydroquinone is particularly preferred.

[0142] Alternatively, it is also possible to first synthesize a complex having a reactive leaving group, e.g., Cl, Br, I, or a boronic acid derivative, instead of a cyanophenyl or cyanobiphenyl group, and then introduce the cyanophenyl or cyanobiphenyl group by a coupling reaction, e.g., Suzuki coupling, in the next step.

[0143] After these processes, if necessary, the compound of Formula (1) of the present invention is purified, for example by recrystallization or sublimation, to a high purity, preferably greater than 99% ( 1 It is possible to obtain (determined by H NMR and / or HPLC).

[0144] For example, for processing the iridium complex of the present invention from a liquid phase by a spin-coating or printing method, a formulation of the iridium complex of the present invention is required. Such a formulation may be, for example, a solution, a dispersion, or an emulsion. 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, veratrol, THF, methyl-THF, THP, chlorobenzene, dioxane, phenoxytoluene, particularly 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, indan, NMP, p-cymene, phenetol, 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, methylbiphenyl, 3-methylbiphenyl, 1-methylnaphthalene, 1-ethylnaphthalene, ethyl octanoate, diethyl sebacate, octyl octanoate, heptylbenzene, It is menthyl isovalerate, cyclohexyl hexanoate, or a mixture of these solvents.

[0145] Accordingly, the present invention also provides a formulation comprising at least one compound of the present invention and at least one additional compound. The additional compound may be, for example, a solvent, in particular one of the solvents mentioned above, or a mixture of these solvents. Alternatively, the additional compound may be an additional organic or inorganic compound likewise used in electronic devices, for example, a matrix material. This additional compound may be polymeric.

[0146] The compound of the present invention may be used as an active ingredient in an electronic device, preferably as a emitter in the emission layer of an organic electroluminescent device. Accordingly, the present invention also provides a use of the compound of the present invention in electronic devices, particularly in organic electroluminescent devices.

[0147] The present invention also provides an electronic device comprising at least one compound of the present invention, in particular an organic electroluminescent device.

[0148] The term "electronic device" is understood to mean any device comprising an anode, a cathode, and at least one layer, wherein the layer comprises at least one organic or organometallic compound. Accordingly, the electronic device of the present invention comprises an anode, a cathode, and at least one layer containing at least one iridium complex of the present invention. A preferred electronic device is 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) (the latter is understood to mean both pure organic solar cells and dye-sensitized solar cells), organic photodetectors, organic photoreceptors, organic field-quench devices (O-FQDs), light-emitting electrochemical cells (LECs), oxygen sensors, and organic laser diodes (O-lasers), wherein at least one layer comprises at least one compound of the present invention. Compounds emitting infrared light are suitable for use in organic infrared electroluminescent devices and infrared sensors. Organic electroluminescent devices are particularly preferred. The active ingredient is generally an organic or inorganic material introduced between the anode and the cathode, such as a charge injection, charge transport, or charge blocking material, but is particularly an emission material and a matrix material. The compound of the present invention exhibits particularly good properties as an emission material in an organic electroluminescent device. Accordingly, a preferred embodiment of the present invention is an organic electroluminescent device. Additionally, the compound of the present invention can be used for the production of singlet oxygen or for photocatalytic action.

[0149] An organic electroluminescent device comprises a cathode, an anode, and at least one emission layer. In addition to these layers, it may also comprise additional 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 an organic or inorganic p / n junction in each case. In this case, one or more hole transport layers are p-doped with, for example, a metal oxide such as MoO3 or WO3, or (per)fluorinated electron-deficient aromatics or electron-deficient cyano-substituted heteroaromatics (e.g., according to JP 4747558, JP 2006-135145, US 2006 / 0289882, WO 2012 / 095143), or quinoid systems (e.g., according to EP1336208), or Lewis acids, or boranes (e.g., according to US 2003 / 0006411, WO 2002 / 051850, WO 2015 / 049030), or carboxylates of elements of main group 3, 4, or 5 (WO 2015 / 018539), and / or one or more It is possible for the electron transport layer to be n-doped.

[0150] Likewise, it is possible to introduce an intermediate layer (e.g., a charge generation layer in a layer system having two or more emission layers, e.g., in white emission OLED components, e.g., in electroluminescent devices, having an exciton blocking function and / or a control charge balance and / or generating a charge) between two emission layers. However, it should be noted that not all of these layers necessarily need to be present.

[0151] In this case, the organic electroluminescent device may contain a single emission layer or multiple emission layers. If multiple emission layers are present, it is desirable that they have multiple emission maxima between 380 nm and 750 nm in total so that the overall result is white emission; in other words, various emission compounds that may exhibit fluorescence or phosphorescence are used in the emission layers. A three-layer system in which three layers exhibit blue, green, and orange or red emission (for basic configurations, see, for example, WO 2005 / 011013), or a system having more than three emission layers is particularly preferred. The system may also be a hybrid system in which one or more layers exhibit fluorescence and one or more other layers exhibit phosphorescence. A preferred embodiment is a tandem OLED. The white-emitting organic electroluminescent device may be used for lighting purposes or otherwise in conjunction with color filters for full-color displays.

[0152] In a preferred embodiment of the present invention, an organic electroluminescent device comprises a compound of the present invention as an emission compound in one or more emission layers.

[0153] When a compound of the present invention is used as a emitting compound in an emitting layer, it is preferably used in combination with one or more matrix materials. A mixture of the compound of the present invention and the matrix material contains 0.1 volume% to 99 volume%, preferably 1 volume% to 90 volume%, more preferably 3 volume% to 40 volume%, and particularly 5 volume% to 15 volume% of the compound of the present invention, based on the total mixture of the emitter and the matrix material. Correspondingly, the mixture contains 99.9 volume% to 1 volume%, preferably 99 volume% to 10 volume%, more preferably 97 volume% to 60 volume%, and particularly 95 volume% to 85 volume% of the matrix material, based on the total mixture of the emitter and the matrix material.

[0154] The matrix material used may generally be any material known for that purpose according to the prior art. The triplet level of the matrix material is preferably higher than the triplet level of the emitter.

[0155] Matrix materials suitable for the compounds of the present invention are, for example, ketones, phosphine oxides, sulfoxides and sulfones, triarylamines, carbazole derivatives according to WO 2004 / 013080, WO 2004 / 093207, WO 2006 / 005627 or WO 2010 / 006680, for example CBP (N,N-biscarbazolylbiphenyl), m-CBP or carbazole derivatives disclosed in WO 2005 / 039246, US 2005 / 0069729, JP 2004 / 288381, EP 1205527, WO 2008 / 086851 or US 2009 / 0134784, for example biscarbazole according to WO 2007 / 063754 or WO 2008 / 056746. Derivatives, indolocarbazole derivatives, e.g., indenocarbazole derivatives according to WO 2010 / 136109 or WO 2011 / 000455, e.g., azacarbazole according to EP 1617710, EP 1617711, EP 1731584, JP 2005 / 347160, e.g., bipolar matrix materials according to WO 2007 / 137725, e.g., silanes according to WO 2005 / 111172, e.g., azaborol or boron ester according to WO 2006 / 117052, e.g., diazasilol derivatives according to WO 2010 / 054729, e.g., diazaphosphol derivatives according to WO 2010 / 054730, e.g., WO It is a triazine derivative according to 2010 / 015306, WO 2007 / 063754 or WO 2008 / 056746, for example, a zinc complex according to EP 652273 or WO 2009 / 062578, for example, a dibenzofuran derivative according to WO 2009 / 148015 or WO 2015 / 169412, or a cross-linked carbazole derivative according to US 2009 / 0136779, WO 2010 / 050778, WO 2011 / 042107 or WO 2011 / 088877.Matrix materials suitable for solution-processed OLEDs are also, for example, polymers according to WO 2012 / 008550 or WO 2012 / 048778, or oligomers or dendrimers according to, for example, Journal of Luminescence 183 (2017), 150-158.

[0156] It may also be desirable to use a plurality of 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 and a triarylamine derivative or a carbazole derivative as a mixed matrix for the compound of the present invention. Likewise, it is desirable to use a mixture of an electrically inactive matrix material (referred to as a "wide bandgap host") that does not significantly participate in charge transport and a charge transport matrix material, even if such materials exist, as described, for example, in WO 2010 / 108579 or WO 2016 / 184540. Likewise, it is desirable to use two electron transport matrix materials, for example, a triazine derivative and a lactam derivative, as described, for example in 2014 / 094964.

[0157] The following are examples of compounds suitable as matrix materials for the compounds of the present invention.

[0158] A preferred biscarbazole that can be used as a matrix material for the compound of the present invention is the structure of the following formulas (10) and (11):

[0159]

[0160] The symbols used in the formula are as follows:

[0161] Ar 1The is an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, preferably 6 to 30 aromatic ring atoms, more preferably 6 to 24 aromatic ring atoms, which are the same or different in each case, and each of these may be substituted by one or more R' radicals, preferably non-aromatic R' radicals;

[0162] A 1 eu NAr 1 , C(R')2, O or S, preferably C(R')2;

[0163] R' is the same or different in each case and is an H, D, F, CN, an alkyl group having 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms, or an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, preferably 6 to 30 aromatic ring atoms, more preferably 6 to 24 aromatic ring atoms, and may be substituted with one or more substituents selected from the group consisting of D, F, CN, or an alkyl group having 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms.

[0164] Preferred embodiments of the compounds of formulas (10) and (11) are compounds of the following formulas (10a) and (11a):

[0165]

[0166] The symbols used in the formula have the definitions given above.

[0167] A preferred dibenzofuran derivative is a compound of the following formula (12):

[0168]

[0169] Oxygen in the formula may also be replaced by sulfur to form dibenzothiophene, and L 1is an aromatic or heteroaromatic ring system having a single bond or 5 to 30 aromatic ring atoms, preferably 6 to 24 aromatic ring atoms, and may also be substituted with one or more R' radicals, but preferably not substituted, and R' and Ar 1 It has the definition given above. Also, here, two Ar atoms bonded to the same nitrogen atom 1 A, or one Ar bonded to the same nitrogen atom 1 It is possible for a group and a single L group to combine to produce, for example, carbazole.

[0170] Preferred carbazoleamines are structures of formulas (13), (14) and (15) below:

[0171]

[0172] L in the food 1 , R' and Ar 1 It has the definition given above.

[0173] Examples of suitable hole-conducting matrix materials are the compounds described in the following table:

[0174]

[0175]

[0176]

[0177]

[0178]

[0179] Preferred triazine or pyrimidine derivatives that can be used as a mixture with the compounds of the present invention are compounds of the following formulas (16) and (17):

[0180]

[0181] Ar in food 1 has the definition given above.

[0182] A triazine derivative of formula (16) is particularly preferred.

[0183] In a preferred embodiment of the present invention, Ar in formulas (16) and (17) 1 It is an aromatic or heteroaromatic ring system that is identical or different in each case and has 6 to 30 aromatic ring atoms, particularly 6 to 24 aromatic ring atoms, and may be substituted with one or more R' radicals.

[0184] Examples of suitable electron transport compounds that may be used as matrix materials together with the compounds of the present invention are the compounds described in the following table:

[0185]

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201]

[0202]

[0203]

[0204]

[0205]

[0206]

[0207] A desirable cathode is a metal alloy or multilayer structure composed of metals having a low work function, various metals, e.g., alkaline earth metals, alkali metals, main group metals, or lanthanides (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Additionally, alloys composed of alkali metals or alkaline earth metals and silver, e.g., alloys composed of magnesium and silver, are suitable. In the case of a multilayer structure, in addition to the metals mentioned, additional metals having a relatively high work function, e.g., Ag, may be used; in this case, combinations of metals such as Mg / Ag, Ca / Ag, or Ba / Ag are generally used. Furthermore, it may be desirable to introduce a thin intermediate layer of a material having a high dielectric constant between the metallic cathode and the organic semiconductor. Examples of materials useful for this purpose include alkali metal or alkaline earth metal fluorides, as well as corresponding oxides or carbonates (e.g., LiF, Li2O, BaF2, MgO, NaF, CsF, Cs2CO3, etc.). Organoalkali metal complexes, for example, Liq (lithium quinolinate), are also useful for this purpose. The thickness of this layer is preferably 0.5 to 5 nm.

[0208] A desirable anode is a material having a high work function. Preferably, the anode has a work function greater than 4.5 eV with respect to vacuum. First, metals with high redox potentials, such as Ag, Pt, or Au, are suitable for this purpose. Second, metal / metal oxide electrodes (e.g., Al / Ni / NiO x , Al / PtO x This may also be desirable. For some applications, at least one of the electrodes must be transparent or partially transparent to allow for irradiation of the organic material (O-SC) or emission of light (OLED / PLED, O-LASER). Here, the preferred anode material is a conductive mixed metal oxide. Indium tin oxide (ITO) or indium zinc oxide (IZO) is particularly preferred. Conductive doped organic materials, particularly conductive doped polymers, such as PEDOT, PANI, or derivatives of these polymers, are additionally preferred. It is also desirable for a p-doped hole transport material to be applied to the anode as a hole injection layer, in which case suitable p-dopants are metal oxides, such as MoO3 or WO3, or (per)fluorinated electron-deficient aromatic systems. Additional suitable p-dopants are compounds NPD9 or HAT-CN (hexacyanohexaazatriphenylene) from Novaled. These layers simplify hole injection into materials with low HOMO, that is, large HOMO in terms of scale.

[0209] In the additional layers, any material generally used according to the prior art for those layers may be used, and a person skilled in the art may combine any of these materials with the materials of the present invention in an electronic device without exercising inventive ability.

[0210] Suitable charge transport materials that can be used in the hole injection or hole transport layer or electron blocking layer or electron transport layer of the organic electroluminescent device of the present invention are, for example, compounds disclosed in Y. Shirota et al., Chem. Rev. 2007, 107(4), 953-1010, or other materials used in these layers according to the prior art. Preferred hole transport materials that can be used for hole transport, hole injection, or electron blocking layers in the electroluminescent device of the present invention include indenofluorenamine derivatives (e.g., according to WO 06 / 122630 or WO 06 / 100896), amine derivatives disclosed in EP 1661888, hexa-azatriphenylene derivatives (e.g., according to WO 01 / 049806), amine derivatives having a fused aromatic system (e.g., according to US 5,061,569), amine derivatives disclosed in WO 95 / 09147, monobenzoindenofluorenamine (e.g., according to WO 08 / 006449), dibenzoindenofluorenamine (e.g., according to WO 07 / 140847), and spirobifluorenamine (e.g., WO 2012 / 034627 or WO 07). These are 2013 / 056565), fluorenamine (e.g., according to EP 2875092, EP 2875699 and EP 2875004), spirodibenzopyranamine (e.g., according to EP 2780325) and dihydroacridine derivatives (e.g., according to WO 2012 / 150001).

[0211] Since the lifespan of the device is severely shortened in the presence of water and / or air, such devices are correspondingly structured (depending on the application), contact-connected, and finally hermetically sealed.

[0212] An organic electroluminescent device characterized by one or more layers being coated by a sublimation process is further preferred. In this case, the material is typically 10 in a vacuum sublimation system. -5 Less than mbar, preferably 10-6 It is applied by deposition at an initial pressure of less than mbar. Additionally, the initial pressure can be even lower or even higher, for example, 10 -7 It may be less than mbar.

[0213] Likewise, an organic electroluminescent device is preferred, characterized in that one or more layers are coated by an OVPD (organic vapor phase deposition) method or with the help of carrier gas sublimation. In this case, the materials are 10 -5 It is applied at a pressure of mbar to 1 bar. A special case of this method is the OVJP (Organic Vapor Jet Printing) method, in which the material is applied directly by a nozzle and thus structured (e.g., MS Arnold et al., Appl. Phys. Lett. 2008 , 92 , 053301).

[0214] An organic electroluminescent device is further preferably characterized in that one or more layers are fabricated from a solution, for example by spin-coating, or by any printing method, for example, screen printing, flexographic printing, offset printing, or nozzle printing, but more preferably by LITI (photo-induced thermal imaging, thermal transfer printing) or inkjet printing. For this purpose, a soluble compound obtained, for example through suitable substitution, is required.

[0215] Organic electroluminescent devices can also be manufactured as hybrid systems by applying one or more layers from a solution and applying one or more other layers by deposition. For example, it is possible to apply an emission layer comprising the metal complex and matrix material of the present invention from a solution, and to apply a hole blocking layer and / or an electron transport layer thereon by deposition under reduced pressure.

[0216] These methods are known to those skilled in the art from a general perspective and can be applied by those skilled in the art without difficulty to organic electroluminescent devices comprising the compounds of Formula (1) or the preferred embodiments described in detail above.

[0217] In relation to the prior art, the electronic device of the present invention, particularly the organic electroluminescent device, is characterized by having a significantly improved lifespan compared to a similar structure that does not have a cyano group on a phenyl or biphenyl substituent. At the same time, the efficiency and voltage are slightly improved. Specific details for implementing the invention

[0218] The present invention is illustrated in detail by the following examples, but is not intended to limit the invention. Those skilled in the art may use the given details without exercising inventive ability to manufacture additional electronic devices of the present invention and thus practice the invention over the entire claimed scope.

[0219] Example:

[0220] Unless otherwise noted, the following syntheses are performed in a dry solvent under a protective gas atmosphere. Metal complexes are further handled in the exclusion of light or under yellow light. Solvents and reagents can be purchased, for example, from Sigma-ALDRICH or ABCR. Each number in brackets or the number cited for individual compounds refers to the CAS number of the compound known in the literature. For compounds that may have multiple tautomeric, isomer, diastereomer, and enantiomer forms, one form is shown in a representative manner.

[0221] A: Synthesis of ligand L:

[0222] Yes L1:

[0223]

[0224] To a mixture of 81.8 g (100 mmol) of 2-(4-{2-[3-(2'-{[trifluoromethanesulfonyl]-4-yl}-4'-(pyridine-2-yl)-[1,1'-biphenyl]-2-yl)-5-{2-[4-(pyridine-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, 1.64 g (4 mmol) of S-Phos was added while vigorously stirring, followed by 449 mg (2 mmol) of palladium(II) Acetate is added, and the mixture is heated under reflux for 12 hours. After cooling, the aqueous phase is removed, the organic phase is substantially concentrated under reduced pressure, the residue is taken up in 500 ml of ethyl acetate, the organic phase is washed twice with 300 ml of water, once with a 2% N-acetylcysteine ​​aqueous solution, and once with 300 ml of saturated sodium chloride solution, and dried over a magnesium sulfate bed. The desiccant is filtered using a silica gel bed in the form of an ethyl acetate slurry, washed with ethyl acetate, the filtrate is concentrated and dried, and the residue is recrystallized from approximately 200 ml of acetonitrile at boiling. Yield: 50.2 g (65 mmol), 65%; Purity: 1 Approximately 98% by 1H NMR.

[0225] The following compounds can be prepared similarly:

[0226]

[0227]

[0228]

[0229]

[0230]

[0231]

[0232] C: Preparation of metal complexes

[0233] Yes Ir(L1):

[0234]

[0235] First, a mixture of 7.71 g (10 mmol) of ligand L1, 4.90 g (10 mmol) of trisacetylacetonatoiridium(III) [15635-87-7], and 120 g of hydroquinone [123-31-9] is placed into a 1000 ml two-necked round-bottom flask equipped with a glass-clad magnetic rod. The flask is equipped with a water separator (for media with a density lower than water) and an air condenser with argon blanketing. The flask is placed in a metal heating bath. The apparatus is purged with argon from the top through the argon blanketing system for 15 minutes, allowing the argon to flow out through the side mouth of the two-necked flask. A glass-clad Pt-100 thermocouple is introduced into the flask through the side mouth of the two-necked flask, with its end positioned directly above the magnetic stirrer rod. Next, the apparatus is insulated with several loose windings of household aluminum foil, and the insulation extends to the center of the rising tube of the water separator. Subsequently, the apparatus is rapidly heated to 240–245°C using a heated laboratory stirrer system (measured by a Pt-100 temperature sensor dipped into the molten stirred reaction mixture). For the next hour, the reaction mixture is maintained at 240–245°C, during which time a small amount of the condensate is distilled and collected in the water separator. After one hour, the mixture is cooled to approximately 190°C, the heating bath 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 double-ended frit, the yellow solid is washed three times with 50 ml of methanol, and then dried under reduced pressure. The solid obtained in this way is dissolved in 200 ml of dichloromethane and filtered through 600 g of silica gel (column diameter about 10 cm) in the form of a dichloromethane slurry in the dark, excluding air, leaving the initially dark-colored component.The core fraction is cut off and concentrated over a rotary evaporator, while MeOH is added dropwise in succession until crystallization occurs. After suction filtration, the product is washed with a small amount of MeOH, dried under reduced pressure, and then carefully excluded from air and light. The yellow product is further purified by four consecutive heat extractions with dichloromethane / i-propanol 1:1 (vv) and then four heat extractions with dichloromethane / acetonitrile (initial input amount of about 200 ml in each case; extraction thimble: standard Soxhlet thimble made from cellulose from Whatman). The loss to the mother liquor can be adjusted through the ratio of dichloromethane (low boiler and good solvent): i-propanol or acetonitrile (high boiler and poor solvent). This should be 3 to 6 weight percent of the amount typically used. Thermal extraction can also be achieved using other solvents such as toluene, xylene, ethyl acetate, butyl acetate, etc. Finally, the product is extracted under high vacuum at p ~ 10. -6 Fractional sublimation occurs at mbar and T ~ 330–430°C. Yield: 4.91 g (5.1 mmol), 51%; Purity: > 99.9% by HPLC.

[0236] Metal complexes are typically obtained as a 1:1 mixture of the Δ isomer and enantiomer. Images of the complexes presented below typically represent only one isomer. When a ligand having three different sub-ligands is used, or when a chiral ligand is used as a racemic mixture, the derived metal complex is obtained as a diastereomer mixture. These can be separated by fractional crystallization or, for example, by chromatography using an automated column system (CombiFlash from A. Semrau). When the chiral ligand is used in an enantiomerically pure form, the derived metal complexes are obtained as a diastereomer mixture, and separation by fractional crystallization or chromatography yields pure enantiomers. The separated diastereomers or enantiomers can be further purified as described above, for example by thermal extraction.

[0237] The following compounds can be prepared similarly:

[0238]

[0239]

[0240]

[0241]

[0242]

[0243]

[0244]

[0245] B: Functionalization of metal complexes

[0246] A) Deuteration of methyl / methylene groups on pyridine ligands:

[0247] 1 mmol of a clean complex (purity > 99.9%) having x methyl / methylene groups and x = 1-6 is heated to about 180°C and dissolved in 50 ml of DMSO-d6 (deuterium level > 99.8%). The solution is stirred at 180°C for 5 minutes. The solution is allowed to cool to 80°C, and a mixture of 10 ml of DMSO-d6 (deuterium level > 99.8%) containing 0.3 mmol of sodium hydride and 5 ml of methanol-d1 (deuterium level > 99.8%) is rapidly added to the solution while stirring well. A clear yellow / orange solution is stirred at 80°C for an additional 30 minutes for complexes having methyl / methylene groups para relative to pyridine nitrogen, or for an additional 6 hours for complexes having methyl / methylene groups meta relative to pyridine nitrogen, then the mixture is cooled with the help of a cold water bath, 20 ml of 1N DCl in D2O is added dropwise starting at about 60°C, the mixture is allowed to cool to room temperature and stirred for an additional 5 hours, the solid is filtered by suction, washed three times with 10 ml of H2O / MeOH (1:1, vv) each time, washed three times with 10 ml of MeOH each time, and dried under reduced pressure. The solid is dissolved in DCM, the solution is filtered through silica gel, and crystallization is induced by concentrating the filtrate under reduced pressure while simultaneously adding MeOH dropwise. Finally, fractional sublimation is performed as described in "C: Preparation of metal complex, Type A". The yield is generally 80-90%, and the deuteration level is > 95%.

[0248] In a similar manner, the following deuteriumized complex can be prepared:

[0249]

[0250] Example: Manufacturing of OLEDs

[0251] 1) Vacuum-treated device:

[0252] The OLED of the present invention and the OLED according to the prior art are manufactured by a general method according to WO 2004 / 058911, which is adjusted to suit the circumstances described herein (variation in layer thickness, materials used).

[0253] Cleaned glass plates coated with 50 nm thick structured ITO (Indium Tin Oxide) (cleaned in a Miele laboratory glass washer with Merck Extran detergent) are baked at 250°C for 15 minutes under nitrogen. The pre-cleaned ITO substrates undergo a two-gas plasma process (oxygen followed by argon) to finally clean the ITO surface and adjust the ITO work function. These coated glass plates form the substrates to which the OLED is applied. All materials are applied by thermal vacuum deposition. In this case, the emission layer always consists of at least one matrix material (host material) and an emission dopant (emitter) added to the matrix material(s) in a specific volume ratio by co-evaporation. Details given in the form of (29.5%:58.5%:12%) as M1:M2:Ir emitters mean that material M1 is present in the layer at a volume ratio of 29.5%, M2 is present at a volume ratio of 58.5%, and the Ir emitter is present at a volume ratio of 12%. Similarly, the electron transport layer is also composed of a mixture of the two materials.

[0254] The OLED basically has the following layer structure: a hole injection layer 1 (HIL1) consisting of an ITO substrate / 5% NDP-9 doped HTM1 (commercially available from Novaled), a hole transport layer 1 (HTL1) consisting of 20 nm / HTM1, a hole transport layer 2 (HTL2) consisting of 40 nm / HTM1, a 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) / a 100 nm-thick aluminum layer as a cathode. The materials used to manufacture the OLED are shown in Table 3.

[0255] 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 %) as a function of luminance, calculated from the current-voltage-luminance characteristics (IUL characteristics) assuming Lambertian emission characteristics, and also the lifetime are determined. The electroluminescence spectrum is determined at a luminance of 1,000 cd / m², and CIE 1931 x and y color coordinates are calculated using this. The lifetime LT90 is defined as the time during operation when the luminance drops to 90% of the starting luminance, starting from a brightness of 10,000 cd / m². OLEDs may initially operate at different starting luminances. The lifetime value can be converted to a value for a different starting luminance using a conversion formula known to those skilled in the art.

[0256] Use of the compound of the present invention as an emitter material in phosphorescent OLEDs

[0257] One use of the compounds of the present invention is as phosphorescent emitter materials in the emission layer of an OLED. The iridium compounds according to Table 3 are used as a comparison with the prior art. The results for OLEDs are collected in order in Table 2.

[0258] As can be seen from the results, when the compound of the present invention is used as an emitter in an OLED, there is a slight improvement in efficiency and voltage, and at the same time a significant improvement in lifespan, for example, compared to the Ir-Ref.1 complex according to the prior art which has the same structure as Ir(L100) but does not contain a cyano group on the biphenyl substituent, the lifespan of the complex Ir(L100) of the present invention is improved by 60%.

[0259]

[0260]

[0261]

[0262]

[0263]

[0264]

Claims

Claim 1 Compound of Formula (1) below. Ir(L) In Formula (1), the ligand L has the structure of Formula (2) below: In the formula, ligand L coordinates to an iridium atom through a position identified by *, and any hydrogen atom not explicitly indicated may also be replaced by D, and the symbols and indices used are as follows: R is the same or different in each case 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 in each case the alkyl group may also be deuterated; R 1 is the same or different in each case 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 in each case the alkyl group may also be deuterated; and wherein 2 adjacent R 1 Radicals can form a ring system together; R 2 is the same or different in each case and is selected from the group consisting of D, a linear alkyl group having 1 to 6 carbon atoms, a branched or cyclic alkyl group having 3 to 6 carbon atoms (wherein each case the alkyl group may also be deuterated), or an optionally deuterated phenyl group that may be substituted by one or more optionally deuterated alkyl groups having 1 to 4 carbon atoms; wherein two adjacent R 2 It is possible for radicals to form a ring system together; m is 1, 2, or 3; n is the same or different in each case and is 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. Claim 2 A compound according to claim 1, characterized in that when m=1, the ligand L has the structure of formula (3a) below, when m=2, the ligand L has the structure of formula (3b) or (3c) below, and when m=3, the ligand L has the structure of formula (3d) or (3e) below. Hydrogen atoms not explicitly indicated in the formula may also be replaced with D, and the symbols and indices have the definitions given in Article 1. Claim 3 A compound according to claim 1, characterized in that when o = 1 and p = 1, the ligand L has the structure of formula (4a) below, and when o = 1 and p = 2, the ligand L has the structure of formula (4b) below. Hydrogen atoms not explicitly indicated in the formula may also be replaced with D, and the symbols and indices have the definitions given in Article 1. Claim 4 A compound according to claim 1, characterized in that the ligand L has the structure of the following formula (7). Hydrogen atoms not explicitly indicated in the formula may also be replaced with D, and the symbols and indices have the definitions given in Article 1. Claim 5 delete Claim 6 A compound according to claim 1, characterized in that the symbol and index are as follows: R is the same or different in each case 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 each alkyl group may also be deuterated; R 1 is the same or different in each case 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 each alkyl group may also be deuteriden; and wherein two adjacent R 1 Radicals can form a ring system together; R 2 is selected from the group consisting of D, which is the same or different in each case and may be substituted by a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 or 4 carbon atoms (wherein the alkyl group may each also be deuterinated), or an optionally deuterinated phenyl group having 1 to 4 carbon atoms; wherein 2 adjacent R 2 Radicals can form a ring system together; m is 1 or 2; n is the same or different in each case, and is 0, 1, or 2; o is 1; or n on the same ligand is 1 and R 2 When ga is a phenyl group, o is 0 or 1; p is 0 or 1; q is 0 or 1; r is 0 or 1. Claim 7 A compound according to claim 1, characterized in that the ligand L has the structure of the following formula (8). Hydrogen atoms not explicitly indicated in the formula may be replaced with D, R, R 1 , R 2 and o have the definition given in the first term, p = 0 or 1, q = 0 or 1 and r = 0 or 1. Claim 8 A compound according to claim 1, characterized in that the ligand L has the structure of the following formula (9). Hydrogen atoms not explicitly indicated in the formula may be replaced with D, R, R 1 and R 2 has the definition given in the first term, and q = 0 or 1 and r = 0 or 1. Claim 9 A method for preparing a compound described in any one of claims 1 to 4 and 6 to 8 by reacting a free ligand L with an iridium alkoxide of the following formula (Ir-1), an iridium ketoketonate of the following formula (Ir-2), an iridium halide of the following formula (Ir-3), an iridium carboxylate of the following formula (Ir-4), or an iridium compound having an alkoxide and / or halide and / or hydroxy and / or ketoketonate radical. In the formula, R has the definition given in claim 1, Hal = F, Cl, Br or I, and the iridium reactant may also take the form of a corresponding hydrate. Claim 10 A formulation comprising at least one compound and at least one solvent as described in any one of claims 1 to 4 and claims 6 to 8. Claim 11 delete Claim 12 An electronic device comprising at least one compound described in any one of claims 1 to 4 and claims 6 to 8. Claim 13 In claim 12, the electronic device is an organic electroluminescent device, and the electronic device is characterized in that the compound is used as an emission compound in one or more emission layers.

Images