Compounds, compositions, organic field light-emitting devices, organic EL display devices, and organic EL lighting.

Abstract

To provide a compound that exhibits good PL quantum yield, excellent solubility in organic solvents, can be used as a green light-emitting material, and provides a good pot life for a composition containing the compound and an organic solvent. [Solution] A compound represented by the following formula 1. TIFF2026074713000033.tif56166

Description

[Technical Field]

[0001] The present invention relates to compounds, compositions, organic electroluminescent devices, organic EL display devices, and organic EL lighting. [Background technology]

[0002] In recent years, there has been active development of organic electroluminescent devices (OLEDs), which use organic thin films as an alternative to those using inorganic materials. Organic electroluminescent devices (sometimes abbreviated as OLEDs) typically have a hole injection layer, a hole transport layer, an organic light-emitting layer, and an electron transport layer between the anode and cathode. Suitable materials are being developed for each of these layers, and development is progressing on the emission colors, including red, green, and blue.

[0003] There are two methods for forming the organic layer of an organic electroluminescent device: vacuum deposition and wet deposition (coating). Vacuum deposition has the advantage of easy stacking, which improves charge injection from the anode and / or cathode and facilitates the containment of excitons in the light-emitting layer. On the other hand, wet deposition does not require a vacuum process, making it easy to produce large-area layers. Furthermore, by using a coating solution that mixes multiple materials with various functions, it is possible to easily form layers containing multiple materials with various functions. For this reason, research and development of organic electroluminescent devices using coating methods has been actively pursued in recent years.

[0004] The light-emitting layer of an organic electroluminescent device requires a compound that exhibits high luminous efficiency and a narrow full width at half maximum, and this compound also needs to be soluble in organic solvents used in wet film deposition methods. For example, Patent Document 1 describes a method to improve the solubility of a structure in which a six-membered aromatic heterocyclic group, such as an azine ring, is bonded to a DABNA skeleton by changing one of the substituents of the azine ring to an alkyl group such as a tert-butyl group, thereby reducing the molecular symmetry and increasing solubility. Patent Document 2 also describes a method to improve the solubility of a compound by adjusting the chain length or the number of substitutions of alkoxy groups or alkyl groups as substituents to an azine ring having acceptor function. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2022 / 092046 [Patent Document 2] International Publication No. 2022 / 121951 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, in the method described in Patent Document 1, the luminescence efficiency as a green light-emitting material was insufficient because the LUMO was not extended across the acceptor structure. Furthermore, in the method described in Patent Document 2, the solubility in organic solvents was not sufficient for using the wet film deposition method in the case of compounds having a structure in which a phenylene ring is bonded to an azine ring. In view of the above-mentioned problems, the present invention aims to provide a compound that has a good PL quantum yield, excellent solubility in organic solvents, can be used as a green light-emitting material, and has a good pot life for a composition containing the compound and an organic solvent. [Means for solving the problem]

[0007] The gist of this invention is as follows:

[0008] One aspect of the present invention is: This relates to the compound represented by the following formula 1.

[0009] [ka]

[0010] (In formula 1, X 1 and X 2 These are, independently, NR, O, or S. Said R is an aromatic hydrocarbon group, an aromatic heterocyclic group or an alkyl group. Benzene ring a and benzene ring b are each independently a benzene ring which may have a substituent. Said X 1 When being N-R, said R may be bonded to said benzene ring a by -O-, -S-, -C(R a )2- or a single bond. Said X 2 When being N-R, said R may be bonded to said benzene ring b by -O-, -S-, -C(R a )2- or a single bond. Said R a is each independently an alkyl group or an aromatic hydrocarbon group. Y 1 , Y 2 and Y 3 are each independently CH or N, and at least one is N. G 1 and G 2 are each independently represented by the following formula 2. m1 and n1 are each independently an integer from 0 to 3. m and n are each independently an integer from 1 to 3. )

[0011]

Chemical formula

[0012] (In formula 2, R 1 and R 2 are each independently an alkyl group having 1 to 12 carbon atoms which may have a substituent. * represents the bonding position with phenylene. )

[0013] Aspect 2 of the present invention relates to a compound in aspect 1, wherein said m1 and n1 are each independently an integer from 0 to 2.

[0014] Aspect 3 of the present invention relates to a compound in aspect 1 or 2, wherein This relates to a compound in which both m and n are 1.

[0015] Aspect 4 of the present invention is a compound in any one of aspects 1 to 3, The aforementioned Y 1 and Y 2 This concerns compounds where N is present.

[0016] Embodiment 5 of the present invention is a compound in any one of embodiments 1 to 4, The aforementioned X 1 and X 2 This concerns compounds where NR is the case.

[0017] Aspect 6 of the present invention is the compound of Aspect 5, This invention relates to a compound in which R is an aromatic hydrocarbon group.

[0018] Embodiment 7 of the present invention relates to any one compound from Embodiments 1 to 6, This relates to a compound represented by the following formula 3.

[0019] [ka]

[0020] (In formula 3, R 3 , R 4 , R 5 and R 6 Each of these is independently a hydrogen atom, an alkyl group which may have substituents, or an aromatic hydrocarbon group. Y 11 , Y 22 and Y 33 Each of them is independently either CH or N, and at least one of them is N. G 11 and G 22 These are each independently represented by Equation 2 above. m2 and n2 are each independent integers between 1 and 3.

[0021] Aspect 8 of the present invention is The present invention relates to a composition comprising one of the compounds described in embodiments 1 to 7 and an organic solvent.

[0022] Aspect 9 of the present invention is This invention relates to an organic electroluminescent device comprising any one compound from embodiments 1 to 7.

[0023] Aspect 10 of the present invention is This invention relates to an organic EL display device, including an organic electroluminescent element according to embodiment 9.

[0024] Aspect 11 of the present invention is This invention relates to organic EL lighting, including an organic electroluminescent element according to embodiment 9. [Effects of the Invention]

[0025] The compound of the present invention is Y 1 ~Y 3 The structure includes a 6-membered ring having Y, and further includes a branched alkyl group having the structure of formula 2 described later, bonded to the 6-membered ring via one benzene ring (when m1=0 and / or n1=0) or a plurality of linked benzene rings (when m1=an integer from 1 to 3 and / or n1=an integer from 1 to 3). 1 ~Y 3 Because at least one of the atoms is nitrogen, the intermolecular cohesive force tends to be high, while the branched structure of the alkyl group tends to suppress strong molecular aggregation. As a result, it is possible to obtain a compound that has a good PL quantum yield, excellent solubility in organic solvents, can be used as a green light-emitting material, and has a good pot life for the composition containing the compound and the organic solvent. Furthermore, when using a wet film deposition method, it is possible to obtain an organic electroluminescent element with high luminescence efficiency. [Brief explanation of the drawing]

[0026] [Figure 1] Figure 1 is a schematic cross-sectional view showing an example of the structure of the organic electroluminescent element of the present invention. [Modes for carrying out the invention]

[0027] The compound according to the embodiment of the present invention has a structure represented by Formula 1.

[0028] [ka]

[0029] (In formula 1, X 1 and X 2 These are, independently, NR, O, or S. The aforementioned R is an aromatic hydrocarbon group, an aromatic heterocyclic group, or an alkyl group. Benzene ring a and benzene ring b are each independently benzene rings which may have substituents. The aforementioned X 1 If NR, then R is -O-, -S-, -C(R a )2- or it may be bonded to the benzene ring a by a single bond. The aforementioned X 2 If NR, then R is -O-, -S-, -C(R a )2- or it may be bonded to the benzene ring b by a single bond. The aforementioned R a Each of these is independently an alkyl group or an aromatic hydrocarbon group. Y 1 , Y 2 and Y 3 Each of them is independently either CH or N, and at least one of them is N. G 1 and G 2 These can be expressed independently by the following equation 2. m1 and n1 are each independent integers between 0 and 3. m and n are each independent integers between 1 and 3.

[0030] [ka]

[0031] (In formula 2, R1 and R 2 Each of these is independently an alkyl group having 1 to 12 carbon atoms, which may have substituents. * indicates the binding site with phenylene.

[0032] <X 1 , X 2 > X 1 and X 2 These are, independently, NR, O, or S. From the viewpoint of easily adjusting the emission wavelength to a preferred range, X is preferred. 1 and X 2 At least one of them is NR, and more preferably X 1 and X 2 That is NR. The aforementioned R is an aromatic hydrocarbon group, an aromatic heterocyclic group, or an alkyl group.

[0033] The number of carbon atoms in the aromatic hydrocarbon group is usually 6 or more, and usually 36 or less, preferably 30 or less, more preferably 24 or less, and even more preferably 18 or less. Examples of aromatic hydrocarbon groups include phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenantrenyl, triphenylene, and naphthylphenyl groups.

[0034] The number of carbon atoms in the aromatic heterocyclic group is usually 3 or more, preferably 4 or more, more preferably 5 or more, and usually 36 or less, preferably 30 or less, more preferably 24 or less, and even more preferably 18 or less. An aromatic heterocyclic group means an aromatic heterocyclic ring having at least one free electron valence. Examples of aromatic heterocyclic rings include pyridine rings, pyrimidine rings, pyrazine rings, triazine rings, imidazole rings, oxazole rings, thiazole rings, benzothiazole rings, benzoxazole rings, benzimidazole rings, quinoline rings, isoquinoline rings, quinoxaline rings, quinazoline rings, naphthyridine rings, and phenanthridine rings. Preferably, the group is a pyridine ring, pyrazine ring, pyrimidine ring, quinoline ring, isoquinoline ring, quinoxaline ring, or quinazoline ring. More preferably, the group is a pyridine ring, quinoline ring, or isoquinoline ring. Most preferably, the group is a pyridine ring.

[0035] The alkyl group typically has 1 or more carbon atoms, preferably 3 or more, more preferably 4 or more, and typically 24 or fewer carbon atoms, preferably 12 or fewer, and more preferably 8 or fewer carbon atoms. The alkyl group may be linear, branched, or cyclic. From the viewpoint of solubility in organic solvents when forming a film of the compound according to the embodiment of the present invention as a light-emitting layer of an organic electroluminescent device by wet deposition, a linear or branched alkyl group is preferred. From the viewpoint of solubility, a linear alkyl group is even more preferred, and a branched alkyl group is even more preferred from the viewpoint of shielding the molecule and reducing unwanted quenching processes due to interaction with the outside. Examples of the alkyl groups mentioned above include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, tert-butyl group, n-hexyl group, cyclohexyl group, dodecyl group, and cyclohexyl group.

[0036] R is preferably an aromatic hydrocarbon group in order to improve the durability of the organic electroluminescent element and to adjust the emission wavelength to a preferred range.

[0037] The aforementioned X 1 If NR, then R is -O-, -S-, -C(R a )It may also be bonded to the benzene ring a by a 2- or single bond. The aforementioned X 2If NR, then R is -O-, -S-, -C(R a ) It may also be bonded to the benzene ring b by a 2- or single bond. When R in NR is an aromatic hydrocarbon group, and this aromatic hydrocarbon group R is bonded to benzene ring a or benzene ring b by a single bond, the structure formed together with benzene ring a or benzene ring b is preferably a carbazole structure.

[0038] The aforementioned R a Each is independently an alkyl group or an aromatic hydrocarbon group. Preferred ranges and specific examples are the same as for R above. From the viewpoint of solubility, R a It is more preferable that it be an alkyl group.

[0039] The hydrogen atoms in R may be independently substituted with substituents. The substituents are selected from the substituent group W listed below. Preferably, the substituents are C1-C12 alkyl groups, C1-C12 alkoxy groups, or C6-C12 aromatic hydrocarbon groups. From the viewpoint of solubility, C2-C6 linear or branched alkyl groups, or phenyl groups having C1-C4 alkyl groups at the 2 and 6 positions are more preferred. Specifically, tert-butyl groups and 2,6-dimethylphenyl groups are particularly preferred.

[0040] <Substituent> Unless otherwise specified, a substituent is any group, but preferably a group selected from the substituent group W listed below. Furthermore, if it is stated that the substituents that may be present are selected from substituent group W, the preferred substituents are also those listed in substituent group W below.

[0041] <Substituent group W> The substituent group W consists of alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryloxy groups, heteroaryloxy groups, alkoxycarbonyl groups, dialkylamino groups, diarylamino groups, arylalkylamino groups, acyl groups, halogen atoms, haloalkyl groups, alkylthio groups, arylthio groups, silyl groups, siloxy groups, cyano groups, aromatic hydrocarbon groups, aromatic heterocyclic groups, aralkyl groups, and heteroaralkyl groups. These substituents may include linear, branched, or cyclic structures.

[0042] More specifically, the substituent group W includes the following structures. A linear, branched, or cyclic alkyl group having 1 or more carbon atoms, preferably 4 or more, 24 or less, preferably 12 or less, more preferably 8 or less, and even more preferably 6 or less. Specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, tert-butyl group, n-hexyl group, cyclohexyl group, dodecyl group, and the like. A linear, branched, or cyclic alkenyl group having typically two or more carbon atoms, typically 24 or fewer, and preferably 12 or fewer. Specific examples include vinyl groups. A linear or branched alkynyl group having typically two or more carbon atoms, typically 24 or fewer, and preferably 12 or fewer. Specific examples include the ethynyl group. An alkoxy group having 1 to 24 carbon atoms, preferably 12 or fewer. Specific examples include a methoxy group and an ethoxy group. An aryloxy group or heteroaryloxy group having 4 or more carbon atoms, preferably 5 or more, and 36 or fewer carbon atoms, preferably 24 or fewer. Specific examples include a phenoxy group, a naphthoxy group, a pyridyloxy group, and the like. An alkoxycarbonyl group having 2 to 24 carbon atoms, preferably 12 or fewer. Specific examples include a methoxycarbonyl group and an ethoxycarbonyl group. A dialkylamino group having 2 to 24 carbon atoms, preferably 12 or fewer. Specific examples include a dimethylamino group and a diethylamino group. A diarylamino group having 10 or more carbon atoms, preferably 12 or more, and 36 or fewer carbon atoms, preferably 24 or fewer. Specific examples include a diphenylamino group, a dicylamino group, and an N-carbazolyl group. An arylalkylamino group having 7 to 36 carbon atoms, preferably 24 carbon atoms. A specific example is the phenylmethylamino group. An acyl group having 2 to 24 carbon atoms, preferably 12 or fewer. Specific examples include an acetyl group and a benzoyl group. Halogen atoms such as fluorine atoms and chlorine atoms. Preferably, fluorine atoms. A haloalkyl group having 1 to 12 carbon atoms, preferably 6 carbon atoms. A specific example is a trifluoromethyl group. An alkylthio group having one or more carbon atoms, usually 24 or fewer, preferably 12 or fewer. Specific examples include a methylthio group and an ethylthio group. An arylthio group having 4 or more carbon atoms, preferably 5 or more, and 36 or fewer carbon atoms, preferably 24 or fewer. Specifically, examples include a phenylthio group, a naphthylthio group, a pyridylthio group, and the like. A silyl group having typically 2 or more carbon atoms, preferably 3 or more, and typically 36 or fewer carbon atoms, preferably 24 or fewer. Specific examples include the trimethylsilyl group and the triphenylsilyl group. A siloxy group having 2 or more carbon atoms, preferably 3 or more, and usually 36 or fewer carbon atoms, preferably 24 or fewer. Specific examples include a trimethylsiloxy group and a triphenylsiloxy group. Cyano group. An aromatic hydrocarbon group having 6 to 36 carbon atoms, preferably 24 or fewer. Specific examples include a phenyl group, a naphthyl group, a group formed by linking multiple phenyl groups, and the like. An aromatic heterocyclic group having 3 or more carbon atoms, preferably 4 or more, and 36 or fewer carbon atoms, preferably 24 or fewer. Specific examples include a thienyl group and a pyridyl group. A linear or branched aralkyl group having typically 8 or more carbon atoms, typically 24 or fewer, and preferably 14 or fewer. Specific examples include phenylpentyl group and phenylhexyl group. A linear or branched heteroaralkyl group having typically 7 or more carbon atoms, typically 18 or fewer, and preferably 13 or fewer. Specific examples include pyridylpentyl groups and pyridylhexyl groups.

[0043] The substituents may include linear, branched, or cyclic structures. When the above substituents are adjacent, adjacent substituents may bond to each other to form a ring. Preferred ring sizes are 4-membered, 5-membered, and 6-membered rings, with specific examples being cyclobutane rings, cyclopentane rings, and cyclohexane rings.

[0044] In order to adjust the solubility in organic solvents, the pot life of the composition containing the compound, and the emission wavelength of the compound to a preferred range when forming a film of the compound according to the embodiment of the present invention by wet film deposition, alkyl groups, alkoxy groups, diarylamino groups, halogen atoms, cyano groups, aromatic hydrocarbon groups, and aralkyl groups are preferred among the substituent group W, alkyl groups, aromatic hydrocarbon groups, and aralkyl groups are more preferred, and alkyl groups are even more preferred.

[0045] Furthermore, each substituent of the substituent group W may have further substituents. Preferably, it has no further substituents, or has an alkyl group having 8 or less carbon atoms, an alkoxy group having 8 or less carbon atoms, or a phenyl group as a further substituent, and more preferably has an alkyl group having 6 or less carbon atoms, an alkoxy group having 6 or less carbon atoms, or a phenyl group as a further substituent. From the viewpoint of charge transport, it is more preferable to have an alkyl group having 6 or less carbon atoms, or an alkoxy group having 6 or less carbon atoms as a further substituent.

[0046] <Y 1 , Y 2 , Y 3 > Y 1 , Y 2 and Y 3Each is independently CH or N, and at least one is N. Y 1 Y 2 and Y 3 For the ring containing Y, 1 , Y, 2 , Y, 3 , it is preferable from the viewpoint of quantum yield that the electron-withdrawing property of the ring is high and it is more likely to adopt a planar structure. Therefore, for Y, 1 , and Y, 2 , it is preferable that two or more of them are N, and it is more preferable that Y, 1 , Y, 2 , Y, 3 are all N.

[0047] <G 1 G 2 > G 1 and G 2 Each is independently represented by the following formula 2.

[0048]

Chemical formula

[0049] (In formula 2, R 1 and R 2 are each independently an alkyl group having 1 to 12 carbon atoms which may have a substituent. * represents the bonding position with phenylene.)

[0050] <R 1 R 2 > R 1 and R 2 are each independently an alkyl group having 1 to 12 carbon atoms which may have a substituent. From the viewpoint of solubility, it is preferable that at least one of R, 1 , R, 2 is an alkyl group having 2 or more carbon atoms. From the viewpoint of charge transport property, it is more preferable that at least one of R, 1 , R, 2 is an alkyl group having 2 to 8 carbon atoms. For R, 1 , R 1 R​​​​​​​​​​​​​​​​​​​​​​​​2 It is even more preferable that at least one of them is an alkyl group having 2 to 6 carbon atoms. The substituent is selected from the substituents listed in substituent group W. Preferably, it is an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 2 carbon atoms, or an aromatic hydrocarbon group having 6 to 12 carbon atoms, and from the viewpoint of charge transport, a methyl group, a methoxy group, or a phenyl group is more preferred.

[0051] <m1、n1> m1 and n1 are each independently integers between 0 and 3. From the viewpoint of broadening the LUMO of the acceptor structure to improve the durability of the compound when it accepts electrons, it is preferable that m1 and n1 are each independently integers between 0 and 2. From the viewpoint of solubility in organic solvents, they are more preferably 0 or 1, and even more preferably both are 0.

[0052] <m、n> m and n are each independent integers between 1 and 3. From the viewpoint of solubility and ease of manufacture, m and n are preferably 1 or 2, and more preferably both are 1.

[0053] <benzene ring a, benzene ring b> Benzene ring a and benzene ring b are each independently benzene rings that may have substituents. That is, the hydrogen atoms of benzene ring a and benzene ring b may each independently be substituted by substituents. Preferred substituents are those selected from substituent group W (hereinafter also referred to as substituent W).

[0054] In order to adjust the solubility in organic solvents and the emission wavelength to a preferred range when forming a film of the compound according to the embodiment of the present invention by wet film deposition, the substituent W is preferably an alkyl group, an alkoxy group, a diarylamino group, a halogen atom, a cyano group, an aromatic hydrocarbon group, an aromatic heterocyclic group, and an aralkyl group, more preferably an alkyl group, a diarylamino group, an aromatic hydrocarbon group, an aromatic heterocyclic group, and even more preferably an alkyl group. From the perspective of solubility, the number of substituents W in benzene ring a and benzene ring b is preferably 1 or more and 2 or less for both, and more preferably 1 for both.

[0055] In addition, in one embodiment, the substituent W may be further substituted with deuterium, F, an alkyl group or an aromatic hydrocarbon group. From the perspective of adjusting the emission wavelength and solubility, preferred substituents are deuterium, F, an alkyl group, an aromatic hydrocarbon group or an aralkyl group, more preferred substituents are deuterium, F, an alkyl group or an aromatic hydrocarbon group, and even more preferred substituents are deuterium or an alkyl group.

[0056] The compound according to an embodiment of the present invention preferably has a structure represented by Formula 3.

[0057]

Chemical Formula

[0058] (In Formula 3, R 3 、R 4 、R 5 and R 6 are each independently a hydrogen atom, an alkyl group which may have a substituent or an aromatic hydrocarbon group. Y 11 、Y 22 and Y 33 are each independently CH or N, and at least one is N. G 11 and G 22 are each independently represented by the said Formula 2. m2 and n2 are each independently an integer from 1 to 3.)

[0059] <R 3 、R 4 、R 5 、R 6 > R 3 、R 4 、R 5 and R 6Each of these is independently a hydrogen atom, an optionally substituted alkyl group, or an aromatic hydrocarbon group, and is preferably a hydrogen atom, an optionally substituted C1-C12 alkyl group, or a C6-C12 aromatic hydrocarbon group. From the viewpoint of solubility, C2-C12 alkyl groups and phenyl groups having alkyl groups as substituents are preferred, and from the viewpoint of charge transport, C2-C6 linear or branched alkyl groups and phenyl groups having C1-C4 alkyl groups at the 2,6 positions are preferred, and tert-butyl groups and 2,6-dimethylphenyl groups are more preferred. The substituent is selected from the substituents listed in substituent group W. Preferably, it is an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 2 carbon atoms, or an aromatic hydrocarbon group having 6 to 12 carbon atoms, and from the viewpoint of charge transport, a methyl group or a methoxy group is particularly preferred.

[0060] <Y 11 , Y 22 , Y 33 > Y 11 , Y 22 and Y 33 Each of these is independently either CH or N, and at least one is N. The high electron-withdrawing nature of this ring and the ease with which it can adopt a more planar structure are preferable from the viewpoint of quantum yield, so Y 11 , Y 22 , Y 33 Preferably, two or more of them are N, and Y 11 and Y 22 It is more preferable that N is Y 11 , Y 22 , Y 33 It is even more preferable that all of them are N.

[0061] <G 11 , G 22 > G 11 and G 22 Each of these is independently represented by Equation 2. R included in Equation 2 1 , R 2 The definition of and *, and R 1 and R 2The preferred range is as described above.

[0062] <m2、n2> m2 and n2 are each an integer between 1 and 3, independently of each other. From the viewpoint of solubility and ease of manufacture, they are preferably 1 or 2, and more preferably both are 1.

[0063] <Molecular weight> When forming a film of the compound according to the embodiment of the present invention by coating, from the viewpoint of solubility in organic solvents and adjusting the emission wavelength to the green emission region, the molecular weight of the compound represented by formula 1 is preferably 759 to 10000. More preferably 800 to 5000, and even more preferably 980 to 3000.

[0064] <Specific examples of compounds represented by formula 1> Examples of compounds represented by Formula 1 include the following:

[0065] [ka]

[0066] [ka]

[0067] [ka]

[0068] [ka]

[0069] [ka]

[0070] [ka]

[0071] [ka]

[0072] [ka]

[0073] [ka]

[0074] [ka]

[0075] The compound according to the embodiment of the present invention can be used in the light-emitting layer of an organic electroluminescent device.

[0076] The aforementioned organic electroluminescent device has a light-emitting layer between the anode and the cathode, and may further include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, and the like. The configuration and manufacturing method of the organic electroluminescent element having a hole injection layer, a hole transport layer, and an electron transport layer may be any known configuration described in International Publication No. 2024 / 004963.

[0077] The light-emitting layer can be manufactured by known methods such as vacuum deposition and wet deposition. Wet deposition is preferred because it allows for easy production of large areas and enables the formation of layers containing multiple materials with various functions. Wet film formation is a method in which a composition dissolved in an organic solvent is applied, and then dried to remove the organic solvent and form a light-emitting layer film. For example, wet film formation methods such as spin coating, dip coating, die coating, bar coating, blade coating, roll coating, spray coating, capillary coating, inkjet, nozzle printing, screen printing, gravure printing, and flexographic printing are employed, and the coated film is dried to form the final film. Among these coating methods, spin coating, spray coating, inkjet, and nozzle printing are preferred. When manufacturing an organic electroluminescent display device equipped with an organic electroluminescent element, inkjet or nozzle printing is preferred, with inkjet being particularly preferred.

[0078] <Composition> A composition according to an embodiment of the present invention may contain a compound according to the present invention and an organic solvent. Such a composition can be used in wet film formation.

[0079] Examples of the aforementioned organic solvents include alkanes such as n-decane, cyclohexane, ethylcyclohexane, decalin, and bicyclohexane; aromatic hydrocarbons such as toluene, xylene, mesitylene, phenylcyclohexane, tetralin, and methylnaphthalene; halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, and trichlorobenzene; and aromatic hydrocarbons such as 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenethole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole, and diphenyl ether. Examples include ethers; aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate; alicyclic ketones such as cyclohexanone, cyclooctanone, and fencone; alicyclic alcohols such as cyclohexanol and cyclooctanol; aliphatic ketones such as methyl ethyl ketone and dibutyl ketone; aliphatic alcohols such as butanol and hexanol; and aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and propylene glycol-1-monomethyl ether acetate (PGMEA). Among these, alkanes, aromatic hydrocarbons, and aromatic esters are preferred from the viewpoint of viscosity and boiling point, with aromatic hydrocarbons and aromatic esters being more preferred.

[0080] The boiling point of the organic solvent is usually 80°C or higher, preferably 100°C or higher, more preferably 120°C or higher, and usually 350°C or lower, preferably 330°C or lower, more preferably 300°C or lower. If the boiling point of the organic solvent is below this range, the film formation stability may decrease during wet film formation due to solvent evaporation from the composition. If the boiling point of the organic solvent is above this range, the film formation stability may decrease during wet film formation due to solvent residue after film formation. From the viewpoint of forming a uniform coating film, it is preferable to combine two or more organic solvents with a boiling point of 150°C or higher.

[0081] The content of the compound relative to the total mass of the composition is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, preferably 30.0% by mass or less, and more preferably 20.0% by mass or less.

[0082] The composition may contain an organometallic compound. The content of the organometallic compound relative to the total mass of the composition is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, preferably 30.0% by mass or less, and more preferably 20.0% by mass or less.

[0083] By setting the content of the aforementioned compound and organometallic compound within this range, holes and electrons can be efficiently injected from adjacent layers (e.g., hole transport layer and hole blocking layer) into the light-emitting layer, thereby reducing the driving voltage.

[0084] Furthermore, the aforementioned compound and organometallic compound may be included in the composition as a single type, or as a combination of two or more types.

[0085] The organometallic compound contains a metal selected from groups 7 to 11 of the long-period periodic table (hereinafter, unless otherwise specified, "periodic table" refers to the long-period periodic table). Preferably, the metals selected from groups 7 to 11 of the periodic table include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold, with iridium or platinum being more preferred. The organometallic compound is preferably a Werner-type complex or an organometallic complex. The ligand of the complex is preferably a ligand in which a (hetero)aryl group is linked to pyridine, pyrazole, phenanthroline, etc., such as a (hetero)arylpyridine ligand or a (hetero)arylpyrazole ligand, with phenylpyridine ligand and phenylpyrazole ligand being particularly preferred. Here, (hetero)aryl refers to an aryl group or a heteroaryl group.

[0086] The composition may further contain other compounds. Examples of other compounds include dibutylhydroxytoluene, known as an antioxidant, and phenols such as dibutylphenol.

[0087] <Structure of Organic Field-Emitting Light> As an example of the structure of an organic electroluminescent element according to an embodiment of the present invention, Figure 1 shows a schematic diagram (cross-section) of an example of the structure of an organic electroluminescent element 8. In Figure 1, 1 represents the substrate, 2 the anode, 3 the hole injection layer, 4 the hole transport layer, 5 the light-emitting layer, 6 the electron transport layer, and 7 the cathode. The configuration of the substrate, anode, hole injection layer, hole transport layer, electron transport layer, and cathode may be any known configuration described in International Publication No. 2024 / 004963.

[0088] <Organic electroluminescent element, method for manufacturing an organic electroluminescent element> The organic electroluminescent element according to the embodiment of the present invention contains the compound according to the embodiment of the present invention, and an organic electroluminescent element with any layer configuration can be manufactured by a known method that includes a step of forming an emissive layer by a wet film deposition method using the composition according to the embodiment of the present invention.

[0089] <Organic EL display device> An organic EL display device (organic electroluminescent device display device) according to an embodiment of the present invention includes an organic electroluminescent device according to an embodiment of the present invention. There are no particular restrictions on the type or structure of the organic EL display device according to an embodiment of the present invention, and it can be assembled according to a conventional method using an organic electroluminescent device according to an embodiment of the present invention. For example, an organic EL display device according to an embodiment of the present invention can be formed by a method such as that described in "Organic EL Display" (Ohmsha, published August 20, 2004, authored by Shizuka Tokito, Chihaya Adachi, and Hideyuki Murata).

[0090] <Organic EL lighting> The organic EL lighting (organic electroluminescent element lighting) according to the embodiment of the present invention includes an organic electroluminescent element according to the embodiment of the present invention. There are no particular restrictions on the type or structure of the organic EL lighting according to the embodiment of the present invention, and it can be assembled according to a conventional method using the organic electroluminescent element according to the embodiment of the present invention. [Examples]

[0091] Embodiments of the present invention will be described below with reference to examples. In the following synthesis examples, all reactions were carried out under a nitrogen atmosphere. The solvents and solutions used in the reactions were degassed by appropriate methods such as nitrogen bubbling. Each evaluation was performed by the following method.

[0092] <Maximum emission wavelength, full width at half maximum> The compounds obtained in the examples and comparative examples described later were dissolved in toluene (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., for spectroscopic analysis) at room temperature, and 1 × 10⁻⁶ of the compounds were prepared. -5 A mol / L solution was prepared. This solution was placed in a quartz cell equipped with a Teflon® stopcock, and nitrogen bubbling was performed for more than 20 minutes. After that, the phosphorescence spectrum was measured at room temperature. The wavelength showing the maximum intensity of the obtained phosphorescence spectrum was defined as the maximum emission wavelength.

[0093] Furthermore, the width of the spectral intensity at half the maximum emission wavelength was defined as the full width at half maximum (FWHM). FWHM was calculated by reading the shorter wavelength (above 0.5) and the longer wavelength (below 0.5) from the spectral data normalized to a converted height of 1, and then taking the difference between them. A maximum emission wavelength of 530 nm or higher and a FWHM of 30 nm or lower can be considered excellent.

[0094] The following equipment was used to measure the emission spectrum. • Equipment: Hamamatsu Photonics K.K. Organic EL quantum yield analyzer C9920-02 • Light source: Monochrome light source L9799-01 • Detector: Multi-channel detector PMA-11 • Excitation light: 380nm

[0095] <PL Quantum Yield> As the luminescence efficiency, the PL quantum yield was measured. The PL quantum yield is an index indicating how efficiently luminescence can be obtained with respect to the light (energy) absorbed by the material. If the PL quantum yield is 0.95 or higher, it can be judged to be excellent.

[0096] Note that the following equipment was used for the measurement of the PL quantum yield. · Equipment: Organic EL Quantum Yield Measurement Device C9920-02 manufactured by Hamamatsu Photonics K.K. · Light source: Monochromatic light source L9799-01 · Detector: Multi-channel detector PMA-11 · Excitation light: 380 nm

[0097] <Precipitation Time> The compounds were mixed with cyclohexylbenzene so that each compound was 0.5% by mass, and a solution dissolved at 100 °C was prepared. After allowing the obtained solution to stand at room temperature, the time until each compound precipitated was confirmed, and a precipitation test evaluation (pot life evaluation) was performed.

[0098] [Example 1 (Compound 1)] <Reaction 1>

[0099] [Chemical Formula]

[0100] Under a nitrogen stream, magnesium (3.05 g, 126 mmol) was placed in 50 ml of dehydrated cyclopentyl methyl ether (CPME). A solution of 3-bromoheptane (25.0 g, 140 mmol) dissolved in 50 ml of dehydrated cyclopentyl methyl ether was slowly added dropwise at 40 °C. Thereafter, the reaction was carried out at 60 °C for 4 hours to obtain Solution A. Under a nitrogen atmosphere, solution A was added to solution B, which consisted of 50 ml of dehydrated cyclopentyl methyl ether, 1,3-dibromobenzene (19.8 g, 83.8 mmol), and 1,1-bis(diphenylphosphine) pherosene dichloropalladium(II) dichloromethane complex (PdCl2(dppf)CH2Cl2; 0.057 g, 0.07 mmol), and the mixture was stirred at 40°C for 5 hours. 15 ml of 1N dilute hydrochloric acid and 20 ml of saturated saline solution were slowly added to the reaction mixture at 0°C. After stirring for 10 minutes, the organic layer obtained by liquid-liquid separation was dried over anhydrous magnesium sulfate and concentrated. Purification by silica gel chromatography was performed to obtain the target product, an oily intermediate 1 (16.8 g).

[0101] <Reaction 2>

[0102] [ka]

[0103] Under a nitrogen atmosphere, magnesium (0.79 g, 32.5 mmol) was added to 20 ml of dehydrated tetrahydrofuran (THF). Solution of intermediate 1 (8.72 g, 34.2 mmol), dissolved in 40 ml of dehydrated tetrahydrofuran at 40°C, was slowly added dropwise. The reaction was then carried out at 60°C for 2 hours to obtain solution C. Under a nitrogen atmosphere, cyanuroxide (3.0 g, 16.3 mmol) was dissolved in 40 ml of dehydrated tetrahydrofuran. Solution C was slowly added dropwise using a cooling bath at 0°C and the mixture was allowed to react for 1 hour. The cooling bath was removed and the mixture was allowed to react for a further 4 hours. 20 ml of deionized water was slowly added, and 50 ml of methylene chloride was added to the concentrated reaction mixture. After stirring for 10 minutes, the mixture was separated. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Purification by silica gel chromatography was performed to obtain the target product, an oily intermediate 2 (4.8 g).

[0104] [ka]

[0105] In a 100 mL round-bottom flask, intermediate 2 (0.72 g, 1.55 mmol), intermediate 3 (synthesized according to the method for producing intermediate 2 described in International Publication No. 2022 / 092046) (0.92 g, 1.2 mmol), [tetrakis(triphenylphosphine)palladium(0)] (0.06 g, 0.048 mmol), 1.8 mL of 2 M tripotassium phosphate aqueous solution, 5 mL of ethanol, and 25 mL of toluene were added, and the mixture was stirred in an oil bath at 90°C for 4.0 hours. After cooling to room temperature, toluene was added, and the mixture was separated. The organic layer was dried over magnesium sulfate and filtered. The solvent was removed from the filtrate under reduced pressure, and the resulting residue was purified by silica gel chromatography to obtain the target product, an orange solid compound 1 (0.54 g). Table 1 shows the results of the precipitation test evaluation for compound 1.

[0106] [Comparative Example 1 (Compound 2)]

[0107] [ka]

[0108] Under a nitrogen atmosphere, 20 ml of dehydrated tetrahydrofuran and magnesium (1.01 g, 41.5 mmol) were placed in a 200 ml flask. At 50°C, 50 ml of a solution of 3-bromo-1-hexylbenzene (10.0 g, 41.5 mmol) dissolved in dehydrated tetrahydrofuran was slowly added dropwise. The reaction was then carried out at 70°C for 3 hours to obtain solution D. Under a nitrogen atmosphere, cyanuroxide (3.8 g, 20.7 mmol) was dissolved in 30 ml of dehydrated tetrahydrofuran. Solution D was then slowly added dropwise using a cooling bath at 0°C and allowed to react for 1 hour. The cooling bath was removed and the reaction was allowed to continue for another 4 hours. 20 ml of deionized water was slowly added, and 40 ml of methylene chloride was added to the concentrated reaction mixture. After stirring for 10 minutes, the mixture was separated. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Purification by silica gel chromatography was performed to obtain the target product, an oily intermediate 4 (2.8 g).

[0109] [ka]

[0110] Under a nitrogen atmosphere, intermediate 4 (0.26 g, 0.59 mmol), intermediate 3 (synthesized according to the method for producing intermediate 2 described in International Publication No. 2022 / 092046) (0.43 g, 0.56 mmol), [tetrakis(triphenylphosphine)palladium(0)] (Pd(PPh3)4; 0.032 g, 0.028 mmol), 0.85 mL of 2 M tripotassium phosphate aqueous solution, 2.5 mL of ethanol, and 15 mL of toluene were added to a 100 mL round-bottom flask and stirred in an oil bath at 90°C for 3.0 hours. After cooling to room temperature, 30 mL of methylene chloride was added to dissolve the insoluble matter. The organic layer was dried over magnesium sulfate and filtered. The solvent was removed from the filtrate under reduced pressure, and the residue obtained was purified by silica gel chromatography to obtain the target product, compound 2 (0.4 g), an orange solid. Table 1 shows the results of the precipitation test evaluation of compound 2.

[0111] [Comparative Example 2 (Compound 3)]

[0112] [ka]

[0113] Under a nitrogen atmosphere, 20 ml of dehydrated tetrahydrofuran and magnesium (0.79 g, 32.5 mmol) were placed in a 200 ml flask. A solution of 1-bromo-3,5-dihexylbenzene (10.6 g, 32.5 mmol) dissolved in 40 ml of dehydrated tetrahydrofuran at room temperature was slowly added dropwise. The mixture was then reacted at 60°C for 2 hours to obtain solution E. Under a nitrogen atmosphere, cyanuroxide (3.0 g, 16.3 mmol) was dissolved in 30 ml of dehydrated tetrahydrofuran. Solution E was slowly added dropwise using a cooling bath at 0°C and the mixture was allowed to react for 1 hour. The cooling bath was removed and the mixture was allowed to react for a further 3 hours. 20 ml of deionized water was slowly added, and 40 ml of methylene chloride was added to the concentrated reaction mixture. After stirring for 10 minutes, the mixture was separated. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Purification by silica gel chromatography was performed to obtain the target product, an oily intermediate 5 (3.2 g).

[0114] [ka]

[0115] Under a nitrogen stream, intermediate 5 (0.303 g, 0.50 mmol), intermediate 3 (synthesized according to the method for producing intermediate 2 described in International Publication No. 2022 / 092046) (0.35 g, 0.46 mmol), [tetrakis(triphenylphosphine)palladium(0)] (Pd(PPh3)4; 0.02 g, 0.018 mmol), 2.0 mL of 2 M tripotassium phosphate aqueous solution, and 8 mL of tetrahydrofuran (THF) were added to a 100 mL round-bottom flask and stirred in an oil bath at 70°C for 2.0 hours. After cooling to room temperature, the precipitate was filtered and washed with tetrahydrofuran. After liquid-liquid separation with methylene chloride and saline solution, the organic layer was dried over magnesium sulfate and filtered. The solvent of the filtrate was removed under reduced pressure, and the resulting residue was purified by silica gel chromatography to obtain the target product, compound 3 (0.3 g), an orange solid. Table 1 shows the results of the precipitation test evaluation for compound 3.

[0116] [Comparative Example 3 (Compound 4)]

[0117] [ka]

[0118] Under a nitrogen atmosphere, 20 ml of dehydrated tetrahydrofuran and magnesium (1.01 g, 41.5 mmol) were placed in a 200 ml flask. A solution of 3-bromo-1-hexylbenzene (10.0 g, 41.5 mmol) dissolved in 40 ml of dehydrated tetrahydrofuran at 40°C was slowly added dropwise. The reaction was then carried out at 70°C for 1 hour to obtain solution F. Under a nitrogen atmosphere, cyanuroxide (15.3 g, 82.9 mmol) was dissolved in 50 ml of dehydrated tetrahydrofuran. Solution F was slowly added dropwise using a cooling bath at 0°C and the mixture was allowed to react for 1 hour. The cooling bath was removed and the mixture was allowed to react for a further 3.5 hours. 20 ml of deionized water was slowly added, and 60 ml of methylene chloride was added to the concentrated reaction mixture. After stirring for 10 minutes, the mixture was separated. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Purification by silica gel chromatography was performed to obtain the target product, an oily intermediate 6 (10.2 g).

[0119] [ka]

[0120] Under a nitrogen atmosphere, 20 ml of dehydrated tetrahydrofuran and magnesium (0.8 g, 32.9 mmol) were placed in a 200 ml flask. A solution of 1-bromo-3,5-dihexylbenzene (10.5 g, 32.3 mmol) dissolved in 40 ml of dehydrated tetrahydrofuran at 40°C was slowly added dropwise. The reaction was then carried out at 70°C for 1 hour to obtain solution G. Under a nitrogen atmosphere, intermediate 6 (10.2 g, 32.9 mmol) was dissolved in 25 ml of dehydrated tetrahydrofuran. Solution G was slowly added dropwise using a cooling bath at 0°C and the mixture was allowed to react for 1 hour. The cooling bath was removed and the mixture was allowed to react for a further 2 hours. 20 ml of deionized water was slowly added, and 80 ml of methylene chloride was added to the concentrated reaction mixture. After stirring for 10 minutes, the organic layer obtained by liquid-liquid separation was dried over anhydrous magnesium sulfate and concentrated. Purification by silica gel chromatography was performed to obtain the target product, an oily intermediate 7 (6.1 g).

[0121] [ka]

[0122] Under a nitrogen stream, intermediate 7 (0.75 g, 1.43 mmol), intermediate 3 (synthesized according to the method for producing intermediate 2 described in International Publication No. 2022 / 092046) (1.0 g, 1.3 mmol), [tetrakis(triphenylphosphine)palladium(0)] (Pd(PPh3)4; 0.0603 g, 0.052 mmol), 3.3 mL of 2 M tripotassium phosphate aqueous solution, and 40 mL of tetrahydrofuran (THF) were added to a 100 mL round-bottom flask and stirred in an oil bath at 70°C for 1.0 hour. After cooling to room temperature, liquid-liquid extraction was performed with methylene chloride and saline solution, and the organic layer was dried over magnesium sulfate and filtered. The solvent was removed from the filtrate under reduced pressure, and the residue was purified by silica gel chromatography to obtain the target product, compound 4 (1.1 g), an orange solid. Table 1 shows the results of the precipitation test evaluation for compound 4.

[0123] [Table 1]

[0124] The compounds in Comparative Examples 1-3 (compounds 2-4) precipitated from the organic solvent quickly, and the ink pot life was insufficient in all cases. In contrast, the compound in Example 1 (compound 1) precipitated from the organic solvent more than 10 times longer than the compounds in Comparative Examples 1-3 (compounds 2-4), and it was found to have a sufficient ink pot life. The compounds of Comparative Examples 1-3 (compounds 2-4) are Y in formula 1. 1 ~Y 3 A 6-membered ring containing a triazine ring (Y 1 ~Y 3In compound 1, the steric hindrance effect due to the hydrogen atom is lost compared to the case where the six-membered ring is a benzene ring, and the six-membered ring and the benzene ring bonded to it take on a nearly planar structure, which is presumed to have led to a tendency for the compound to aggregate. On the other hand, compound 1, like the compounds of Comparative Examples 1-3 (compounds 2-4), has a nearly planar structure in which the six-membered ring and the benzene ring bonded to it take on a nearly planar structure, but the branched alkyl group is in a position nearly perpendicular to the plane, which is presumed to have suppressed the aggregation of the compound and resulted in a sufficient ink pod life. Furthermore, compound 1 has a PL quantum yield of 0.95 or higher, suggesting that it can be used to obtain a highly efficient green light-emitting device. [Industrial applicability]

[0125] The organic electroluminescent element and the composition according to the embodiment of the present invention can be suitably used, for example, in organic EL display devices and organic EL lighting. [Explanation of symbols]

[0126] 1 circuit board 2 Anode 3. Hole injection layer 4. Hole transport layer 5. Emitting layer 6 Electron transport layer 7 Cathode 8 Organic electroluminescent element

Claims

1. The compound represented by the following formula 1. 【Chemistry 1】 (In formula 1, X １ and X ２ These are, independently, N-R, O, or S. The R is an aromatic hydrocarbon group, an aromatic heterocyclic group, or an alkyl group. Benzene ring a and benzene ring b are each independently benzene rings which may have substituents. The aforementioned X １ If N-R, then R is -O-, -S-, -C(R ａ ) ２ - Alternatively, it may be bonded to the benzene ring a by a single bond. The aforementioned X ２ If N-R, then R is -O-, -S-, -C(R ａ ) ２ - Alternatively, it may be bonded to the benzene ring b by a single bond. The aforementioned R ａ is each independently an alkyl group or an aromatic hydrocarbon group. Y １ , Y ２ and Y ３ Each of them is independently either CH or N, and at least one is N. G １ and G ２ These are each independently represented by the following equation 2. m1 and n1 are each independent integers between 0 and 3. m and n are each independent integers between 1 and 3. 【Chemistry 2】 (In formula 2, R １ and R ２ Each of these is independently an alkyl group having 1 to 12 carbon atoms, which may have substituents. * indicates the binding position with phenylene.

2. The compound according to claim 1, wherein m1 and n1 are each independently integers from 0 to 2.

3. The compound according to claim 1, wherein both m and n are 1.

4. The aforementioned Y １ and Y ２ The compound according to claim 1, wherein is N.

5. The aforementioned X １ and X ２ The compound according to claim 1, wherein N-R.

6. The compound according to claim 5, wherein R is an aromatic hydrocarbon group.

7. The compound according to claim 1, represented by the following formula 3. 【Transformation 3】 (In formula 3, R ３ , R ４ , R ５ and R ６ Each of these is independently a hydrogen atom, an alkyl group which may have substituents, or an aromatic hydrocarbon group. Y １１ , Y ２２ and Y ３３ Each of them is independently either CH or N, and at least one is N. G １１ and G ２２ These are each independently represented by formula 2 above. m² and n² are each independent integers between 1 and 3.

8. A composition comprising the compound according to any one of claims 1 to 7 and an organic solvent.

9. An organic electroluminescent device comprising the compound described in any one of claims 1 to 7.

10. An organic electroluminescent display device comprising the organic electroluminescent element described in claim 9.

11. Organic electroluminescent lighting comprising the organic electroluminescent element described in claim 9.

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